JP2015056294A - Dye-sensitized solar cell element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dye-sensitized solar cell element having superior photoelectric conversion characteristics and durability.SOLUTION: A dye-sensitized solar cell element has at least one dye-sensitized solar cell including a first electrode having a transparent substrate and a transparent conductive layer provided thereon, a second electrode facing the first electrode and including a metal substrate, and a conductive material for connection with the metal substrate of the second electrode. The conductive material contains metallic particles and a binder resin, and the ratio S of the area S2 of a nonconductive region occupying the total area S1 of an observation region in the cross section of the conductive material, excepting the metallic particles from the observation region, is 40-80 area%.

Description

  The present invention relates to a dye-sensitized solar cell element.

  As a photoelectric conversion element, a dye-sensitized solar cell element has attracted attention because it is inexpensive and can provide high photoelectric conversion efficiency, and various developments have been made on the dye-sensitized solar cell element.

  The dye-sensitized solar cell element includes at least one dye-sensitized solar cell, and the dye-sensitized solar cell generally includes a working electrode and a counter electrode. And as one base material of a working electrode or a counter electrode, since an electron can be exchanged between the adjacent dye-sensitized solar cell or the exterior, a metal substrate may be used.

  For example, Patent Document 1 below has a plurality of dye-sensitized solar cells, uses a metal substrate as a counter substrate of each dye-sensitized solar cell, and one of two adjacent dye-sensitized solar cells. A photoelectric conversion element module is disclosed in which a metal substrate as a counter electrode of a dye-sensitized solar cell and a working electrode of the other dye-sensitized solar cell are connected by a conductive member.

International Publication No. 2009/141964

  However, the photoelectric conversion element module described in Patent Document 1 described above still has room for improvement in terms of photoelectric conversion characteristics and durability.

  This invention is made | formed in view of the said situation, and it aims at providing the dye-sensitized solar cell element which has the outstanding photoelectric conversion characteristic and durability.

  This inventor repeated earnest research in order to solve the said subject. As a result, it has been found that the above-described problems can be solved by the following invention.

  That is, the present invention includes at least one dye-sensitized solar cell, and the dye-sensitized solar cell includes a first electrode having a transparent substrate and a transparent conductive layer provided on the transparent substrate, and the first electrode. A second electrode including a metal substrate and a conductive material connected to the metal substrate of the second electrode, the conductive material including metal particles and a binder resin, Dye-sensitized solar cell in which the non-conductive region ratio S, which is the ratio of the area S2 of the non-conductive region excluding the metal particles from the observation region in the total area S1 of the observation region in the cross section, is 40 to 80 area% It is an element.

  According to the dye-sensitized solar cell element of the present invention, even when the dye-sensitized solar cell element is placed in an environment where the temperature change is large and the metal particles expand or contract, When the conductive region ratio S is within the above range, the stress between the metal particles is relieved, and the breakage of the conductive material can be sufficiently suppressed. As a result, it is possible to have excellent durability. In addition, in the observation region of the cross section of the conductive material, the non-conductive region ratio S is in the above range, so that an increase in contact resistance between the second electrode and the conductive material can be sufficiently suppressed, and the current can be sufficiently increased. Therefore, it is possible to have excellent photoelectric conversion characteristics. Therefore, according to the dye-sensitized solar cell element of the present invention, it is possible to have excellent photoelectric conversion characteristics and durability.

  In the dye-sensitized solar cell element, the conductive material preferably includes the binder resin and voids between the metal particles.

  In this case, since the conductive material further includes voids between the metal particles, even if the dye-sensitized solar cell element is placed in an environment with a large temperature change and the metal particles expand or contract, The stress is more sufficiently relaxed and the breakage of the conductive material can be more sufficiently suppressed. As a result, it becomes possible to have more excellent durability.

  In the dye-sensitized solar cell element, the metal particles are, for example, silver particles.

  The dye-sensitized solar cell element further includes a connection terminal connected to the conductive material of the at least one dye-sensitized solar cell, and the connection terminal includes the conductive material to which the connection terminal is connected. Provided on the insulated transparent conductive layer adjacent to the transparent conductive layer of the sensitized solar cell, the connection terminal includes metal particles, and the metal particles included in the connection terminal are included in the conductive material. It is preferable to be composed of the same metal as the particles.

  In this case, since the metal particles contained in the connection terminal and the conductive material are composed of the same metal, the connection terminal and the conductive material are compared with the case where the metal particles contained in the connection terminal and the conductive material are composed of different metals. Can be more sufficiently improved. For this reason, it becomes possible to improve the connection reliability in a dye-sensitized solar cell element more.

  The dye-sensitized solar cell element further includes a connection terminal connected to the conductive material of the at least one dye-sensitized solar cell, and the connection terminal includes the conductive material to which the connection terminal is connected. Provided on the insulated transparent conductive layer adjacent to the transparent conductive layer of the dye-sensitized solar cell, the connection terminal includes metal particles, and the non-conductive region ratio S in the conductive material is It is preferably larger than the non-conductive region ratio T which is the ratio of the area T2 of the non-conductive region excluding the metal particles from the observation region in the total area T1 of the observation region in the cross section.

  In this case, the bonding strength between the connection terminal and the transparent conductive layer is greater than the case where the non-conductive area ratio S in the conductive material is equal to or less than the non-conductive area ratio T in the connection terminal. The contact resistance with the layer becomes smaller.

  When the dye-sensitized solar cell element includes a plurality of the dye-sensitized solar cells, the dye-sensitized solar cell element is insulated next to the transparent conductive layer of the dye-sensitized solar cell having the conductive material to which the connection terminal is connected. The transparent conductive layer constitutes a transparent conductive layer of a dye-sensitized solar cell adjacent to the dye-sensitized solar cell having the conductive material to which the connection terminal is connected, or a part of the dye-sensitized solar cell. It is a transparent conductive layer that does not.

  In the present invention, the “non-conductive region ratio S” refers to the ratio of the non-conductive region in the observation region when the cross section of the conductive material is observed with a scanning electron microscope. Similarly, the “non-conductive area ratio T” refers to the ratio of the non-conductive area in the observation area when the cross section of the connection terminal is observed with a scanning electron microscope.

  ADVANTAGE OF THE INVENTION According to this invention, the dye-sensitized solar cell element which has the outstanding photoelectric conversion characteristic and durability is provided.

It is a cut surface end view showing a first embodiment of a dye-sensitized solar cell element of the present invention. It is a top view which shows a part of 1st Embodiment of the dye-sensitized solar cell element of this invention. It is a top view which shows the pattern of the transparent conductive layer in the dye-sensitized solar cell element of FIG. FIG. 3 is a schematic view showing a partial region of a cross section of the conductive material of FIG. It is a top view which shows the 1st integrated sealing part of FIG. It is a top view which shows the 2nd integrated sealing part of FIG. It is a cut surface end view along the VII-VII line of FIG. FIG. 3 is a schematic view showing a partial region of a cross section of the connection terminal of FIG. It is a top view which shows the working electrode which formed the connection part for fixing a back seat | sheet. It is a top view which shows the 1st integrated sealing part formation body for forming the 1st integrated sealing part of FIG. It is a top view which shows a part of 2nd Embodiment of the dye-sensitized solar cell element of this invention. It is a top view which shows a part of 3rd Embodiment of the dye-sensitized solar cell element of this invention. It is a top view which shows a part of 4th Embodiment of the dye-sensitized solar cell element of this invention. It is a top view which shows a part of 5th Embodiment of the dye-sensitized solar cell element of this invention.

  Hereinafter, preferred embodiments of the dye-sensitized solar cell element of the present invention will be described in detail with reference to FIGS. FIG. 1 is a cross-sectional end view showing a first embodiment of the dye-sensitized solar cell element of the present invention, and FIG. 2 is a plan view showing a part of the first embodiment of the dye-sensitized solar cell element of the present invention. 3 is a plan view showing the pattern of the transparent conductive layer in the dye-sensitized solar cell module of FIG. 1, FIG. 4 is a schematic view showing a partial region of the cross section of the conductive material of FIG. 2, and FIG. 1 is a plan view showing the first integrated sealing portion in FIG. 1, FIG. 6 is a plan view showing the second integrated sealing portion in FIG. 1, and FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. FIG. 8 is a schematic diagram showing a partial region of the cross section of the connection terminal in FIG. 2, and FIG. 9 is a plan view showing a working electrode in which a connecting portion for fixing the insulating material and the backsheet is formed. is there.

  As shown in FIG. 1, a dye-sensitized solar cell module (hereinafter sometimes referred to as “DSC module”) 100 as a dye-sensitized solar cell element includes a plurality of transparent substrates 11 (four in FIG. 1). The dye-sensitized solar cell (hereinafter sometimes referred to as “DSC”) 50 and a back sheet 80 provided on the one surface 11a side of the transparent substrate 11 of the DSC 50 are included. As shown in FIG. 2, the plurality of DSCs 50 are connected in series by a conductive material 60P. Hereinafter, for convenience of description, the four DSCs 50 in the DSC module 100 may be referred to as DSCs 50A to 50D.

  As shown in FIG. 1, each of the plurality of DSCs 50 includes a working electrode 10 having a conductive substrate 15, a counter electrode 20 facing the conductive substrate 15, and an annular sealing that joins the conductive substrate 15 and the counter electrode 20. 30A. A cell space formed by the conductive substrate 15, the counter electrode 20, and the annular sealing portion 30 </ b> A is filled with an electrolyte 40.

  The counter electrode 20 includes a metal substrate 21 and a catalyst layer 22 provided on the working electrode 10 side of the metal substrate 21 to promote a catalytic reaction. In two adjacent DSCs 50, the counter electrodes 20 are separated from each other. In the present embodiment, the second electrode is constituted by the counter electrode 20.

  As shown in FIGS. 1 and 2, the working electrode 10 includes a conductive substrate 15 and at least one oxide semiconductor layer 13 provided on the conductive substrate 15. The conductive substrate 15 includes a transparent substrate 11, a transparent conductive layer 12 provided on one surface 11a of the transparent substrate 11, an insulating material 33 provided on the transparent substrate 11, and a connection terminal provided on the transparent conductive layer 12. 16. The oxide semiconductor layer 13 is disposed inside the annular sealing portion 30A. A photosensitizing dye is adsorbed on the oxide semiconductor layer 13.

  The transparent substrate 11 is used as a common transparent substrate for the DSCs 50A to 50D. In the present embodiment, the first electrode is constituted by the conductive substrate 15.

  As shown in FIGS. 2 and 3, the transparent conductive layer 12 is composed of transparent conductive layers 12 </ b> A to 12 </ b> F that are provided in an insulated state. That is, the transparent conductive layers 12A to 12F are arranged with the groove 90 interposed therebetween. Here, the transparent conductive layers 12A to 12D constitute the transparent conductive layers 12 of the plurality of DSCs 50A to 50D, respectively. The transparent conductive layer 12E is arranged so as to be bent along the sealing portion 30A. The transparent conductive layer 12F is an annular transparent conductive layer 12 for fixing the peripheral edge 80a of the back sheet 80 (see FIG. 1).

  As shown in FIG. 3, each of the transparent conductive layers 12A to 12D includes a rectangular main body portion 12a having a side edge portion 12b and a protruding portion 12c protruding sideways from the side edge portion 12b of the main body portion 12a. Have.

  As shown in FIG. 2, in the DSC 50C, the protruding portion 12c of the transparent conductive layer 12C among the transparent conductive layers 12A to 12D includes a protruding portion 12d that protrudes laterally with respect to the arrangement direction X of the DSCs 50A to 50D, and a protruding portion. It has a facing portion 12e extending from 12d and facing the main body portion 12a of the adjacent DSC 50D through a groove 90.

  Also in the DSC 50B, the protruding portion 12c of the transparent conductive layer 12B has a protruding portion 12d and a facing portion 12e. Also in the DSC 50A, the protruding portion 12c of the transparent conductive layer 12A has a protruding portion 12d and a facing portion 12e.

  The DSC 50D is already electrically connected to the DSC 50C, and there is no other DSC 50 to be connected. For this reason, in the DSC 50D, the protruding portion 12c of the transparent conductive layer 12D does not have the facing portion 12e. In other words, the protruding portion 12c of the transparent conductive layer 12D is constituted only by the overhang portion 12d.

  However, the transparent conductive layer 12D connects the first current extraction portion 12f for extracting the current generated in the DSC module 100 to the outside, the first current extraction portion 12f, and the main body portion 12a, and the transparent conductive layers 12A to 12C. And a connecting portion 12g extending along the side edge portion 12b. The first current extraction portion 12f is disposed around the DSC 50A and on the opposite side of the transparent conductive layer 12B with respect to the transparent conductive layer 12A.

  On the other hand, the transparent conductive layer 12E also has a second current extraction portion 12h for extracting the current generated in the DSC module 100 to the outside. The second current extraction portion 12h is around the DSC 50A and is a transparent conductive layer. It is arranged on the opposite side to the transparent conductive layer 12B with respect to 12A. The first current extraction portion 12f and the second current extraction portion 12h are arranged adjacent to each other through the groove 90B (90) around the DSC 50A. Here, the groove 90 is formed along the edge of the first groove 90A formed along the edge of the main body 12a of the transparent conductive layer 12 and the portion of the transparent conductive layer 12 excluding the main body 12a. The second groove 90 </ b> B intersects with the peripheral edge 80 a of the backsheet 80.

  Moreover, the connection terminal 16 is provided on each protrusion part 12c of transparent conductive layer 12A-12C which comprises a part of DSC50, and the transparent conductive layer 12E which does not comprise a part of DSC50. Each connection terminal 16 is connected to the conductive material 60P, and is sealed outside the sealing portion 30A, extending along the sealing portion 30A, and from the conductive material connecting portion 16A to the outside of the sealing portion 30A. And a conductive material non-connecting portion 16B extending along the portion 30A. In the present embodiment, in the transparent conductive layers 12A to 12C, at least the conductive material connection portion 16A of the connection terminals 16 is provided on the facing portion 12e of the projection portion 12c, and the main body portion of the adjacent DSC 50 to be connected. 12a. In the transparent conductive layer 12E, the conductive material connection portion 16A of the connection terminals 16 faces the main body portion 12a of the adjacent DSC 50A to be connected. The width of the conductive material non-connecting portion 16B is narrower than the width of the conductive material connecting portion 16A. Here, the widths of the conductive material connecting portion 16A and the conductive material non-connecting portion 16B are constant. Note that the width of the conductive material connecting portion 16A is the length in the direction orthogonal to the extending direction of the conductive material connecting portion 16A and means the narrowest width among the widths of the conductive material connecting portion 16A. The width of the portion 16B is the length in a direction orthogonal to the extending direction of the conductive material non-connecting portion 16B and means the narrowest width among the widths of the conductive material non-connecting portion 16B.

  Then, the conductive material connecting portion 16A of the connection terminal 16 provided on the protruding portion 12c of the transparent conductive layer 12C in the DSC 50C and the metal substrate 21 of the counter electrode 20 in the adjacent DSC 50D are connected via the conductive material 60P. The conductive material 60P is disposed so as to pass over the sealing portion 30A. Similarly, the conductive material connection portion 16A of the connection terminal 16 in the DSC 50B and the metal substrate 21 of the counter electrode 20 in the adjacent DSC 50C are connected via the conductive material 60P, and adjacent to the conductive material connection portion 16A of the connection terminal 16 in the DSC 50A. The metal of the counter electrode 20 in the DSC 50B is connected to the metal substrate 21 of the counter electrode 20 through the conductive material 60P, and the metal of the conductive material connection portion 16A of the connection terminal 16 on the transparent conductive layer 12E that does not form part of the DSC 50 and the metal of the counter electrode 20 in the adjacent DSC 50A. The substrate 21 is connected via a conductive material 60P.

  Here, the conductive material 60P includes metal particles, a binder resin, and voids. Here, the binder resin and the gap are provided between the metal particles. Further, as shown in FIG. 4, the ratio of the non-conductive region which is the ratio of the area S2 of the non-conductive region 97c excluding the metal particles 97b from the observation region 97a in the total area S1 of the observation region 97a in the cross section of the conductive material 60P. S (= S2 / S1) is 40 to 80 area%.

  External connection terminals 18a and 18b are provided on the first current extraction portion 12f and the second current extraction portion 12h, respectively.

  As shown in FIG. 1, the sealing part 30A is provided so as to overlap the annular first sealing part 31A provided between the conductive substrate 15 and the counter electrode 20, and the first sealing part 31A. It has the 2nd sealing part 32A which clamps the edge part 20a of the counter electrode 20 with 31 A of 1 sealing parts. Then, as shown in FIG. 5, adjacent first sealing portions 31 </ b> A are integrated to form a first integrated sealing portion 31. In other words, the first integrated sealing portion 31 includes an annular portion (hereinafter referred to as “annular portion”) 31 a that is not provided between two adjacent counter electrodes 20 and two adjacent counter electrodes 20. A portion (hereinafter referred to as a “partition portion”) 31 b that is provided between them and partitions the inner opening 31 c of the annular portion 31 a. Further, as shown in FIG. 6, the second sealing portions 32 </ b> A are integrated between the adjacent counter electrodes 20 to constitute a second integrated sealing portion 32. The second integrated sealing portion 32 is provided between an annular portion (hereinafter referred to as “annular portion”) 32 a that is not provided between two adjacent counter electrodes 20 and two adjacent counter electrodes 20. And a portion (hereinafter referred to as “partition portion”) 32b that partitions the inner opening 32c of the annular portion 32a.

  Further, as shown in FIG. 1, a glass is interposed between the first sealing portion 31 </ b> A and the groove 90 so as to enter the groove 90 between the adjacent transparent conductive layers 12 </ b> A to 12 </ b> F and straddle the adjacent transparent conductive layer 12. An insulating material 33 made of frit is provided. More specifically, the insulating material 33 enters the first groove 90A formed along the edge of the main body 12a of the transparent conductive layer 12 in the groove 90, and the main body forming the first groove 90A. The edge of the portion 12a is also covered.

  As shown in FIG. 7, the width P of the bonding portion between the surface of the counter electrode 20 on the conductive substrate 15 side and the partition portion 31 b of the first integrated sealing portion 31 is the same as that of the counter electrode 20 on the conductive substrate 15 side. It is narrower than the width Q of the bonding portion between the surface and the annular portion 31 a of the first integrated sealing portion 31. Furthermore, the width R of the partition part 31 b of the first integrated sealing part 31 is 100% or more and less than 200% of the width T of the annular part 31 a of the first integrated sealing part 31.

  The second integrated sealing portion 32 includes a main body portion 32 d provided on the opposite side of the counter electrode 20 from the working electrode 10, and an adhesive portion 32 e provided between the adjacent counter electrodes 20. The second integrated sealing portion 32 is bonded to the first integrated sealing portion 31 by an adhesive portion 32e.

  As shown in FIG. 1, a back sheet 80 is provided on the surface 11 a side of the transparent substrate 11. The backsheet 80 includes a laminate 80A including a weather resistant layer and a metal layer, and an adhesive portion 80B that is provided on the opposite side of the laminate 80A from the metal layer and adheres to the conductive substrate 15 via the connecting portion 14. Including. Here, the bonding portion 80B is for bonding the back sheet 80 to the conductive substrate 15, and as long as it is formed on the peripheral portion of the stacked body 80A as shown in FIG. However, the bonding portion 80B may be provided on the entire surface on the DSC 50 side of the stacked body 80A. The peripheral edge portion 80a of the back sheet 80 is connected to the transparent conductive layers 12D, 12E, and 12F of the transparent conductive layer 12 through the connecting portion 14 by the bonding portion 80B. Here, the bonding portion 80B is separated from the sealing portion 30A of the DSC 50. The connecting portion 14 is also separated from the sealing portion 30A. The space inside the back sheet 80 and outside the sealing portion 30A is not filled with the electrolyte 40.

  As shown in FIG. 2, in the transparent conductive layer 12D, the current collector wiring 17 having a lower resistance than that of the transparent conductive layer 12D extends so as to pass through the main body portion 12a, the connection portion 12g, and the current extraction portion 12f. . The current collecting wiring 17 is arranged so as not to intersect the connecting portion 14 between the back sheet 80 and the conductive substrate 15. In other words, the current collecting wiring 17 is disposed on the inner side than the connecting portion 14.

  As shown in FIG. 2, bypass diodes 70A to 70D are connected in parallel to the DSCs 50A to 50D, respectively. Specifically, the bypass diode 70A is fixed on the partition part 32b of the second integrated sealing part 32 between the DSC 50A and the DSC 50B, and the bypass diode 70B is a second integrated between the DSC 50B and the DSC 50C. The bypass diode 70C is fixed on the partition part 32b of the sealing part 32, and is fixed on the partition part 32b of the second integrated sealing part 32 between the DSC 50C and the DSC 50D by a conductive material 60Q. The bypass diode 70D is fixed on the sealing portion 30A of the DSC 50D. A conductive material 60Q is fixed to the metal substrate 21 of the counter electrode 20 so as to pass through the bypass diodes 70A to 70D. Here, it is preferable that the conductive material 60Q covers at least a part of the surface opposite to the second integrated sealing portion 32 among the surfaces of the bypass diodes 70A to 70D. In this case, the adhesion between each of the bypass diodes 70A to 70D and the metal substrate 21 is further improved. Further, a conductive material 60P branches from the conductive material 60Q between the bypass diodes 70A and 70B, between the bypass diodes 70B and 70C, and between the bypass diodes 70C and 70D, and the conductive material connecting portion 16A on the transparent conductive layer 12A, the transparent conductive layer The conductive material connection portion 16A on 12B and the conductive material connection portion 16A on the transparent conductive layer 12C are connected to each other. The conductive material 60P is also fixed to the metal substrate 21 of the counter electrode 20 of the DSC 50A, and the conductive material 60P connects the bypass diode 70A and the conductive material connection portion 16A of the connection terminal 16 on the transparent conductive layer 12E. . Further, the bypass diode 70D is connected to the transparent conductive layer 12D through the conductive material 60P.

  Further, as shown in FIG. 1, a desiccant 95 is provided on the counter electrode 20 of each DSC 50.

  According to the DSC module 100, the conductive material 60P includes metal particles, a binder resin, and voids, and the non-conductive region ratio S in the observation region 97a of the cross section of the conductive material 60P is 40 to 80 area%. For this reason, even if the DSC module 100 is placed in an environment where the temperature change is large and the metal particles in the conductive material 60P expand or contract, the non-conductive region ratio S in the observation region 97a of the cross section of the conductive material 60P is within the above range. By being inside, the stress between metal particles is relieve | moderated and the failure | damage of the electrically conductive material 60P can fully be suppressed, As a result, it becomes possible to have outstanding durability. Further, in the observation region 97a of the cross section of the conductive material 60P, the non-conductive region ratio S is within the above range, so that it is possible to sufficiently suppress an increase in contact resistance between the counter electrode 20 and the conductive material 60P. As a result, it is possible to have excellent photoelectric conversion characteristics. Therefore, according to the DSC module 100, it is possible to have excellent photoelectric conversion characteristics and durability.

  In the DSC module 100, since the conductive material 60P includes voids between the metal particles, even if the DSC module 100 is placed in an environment with a large temperature change and the metal particles expand or contract, The stress is sufficiently relaxed, and the breakage of the conductive material 60P can be more sufficiently suppressed. As a result, it becomes possible to have more excellent durability.

  Further, in the DSC module 100, a groove 90 is formed along the edge of the transparent conductive layer 12, and the groove 90 is an edge of the main body 12a of the transparent conductive layer 12 disposed inside the annular sealing portion 30A. The first groove 90A is formed along the first groove 90A. The insulating material 33 made of glass frit enters the first groove 90A, and the insulating material 33 also covers the edge of the main body portion 12a forming the first groove 90A. For this reason, even if a crack is formed along the groove 90 in the transparent substrate 11 and below the groove 90, and the crack is connected to the edge of the main body 12 a, the crack is sealed. Intrusion of moisture from the outside of the stop 30A is sufficiently suppressed by the insulating material 33. In particular, in the DSC module 100, since the insulating material 33 that covers the edge of the main body portion 12a that forms the first groove 90A and enters the first groove 90A is made of glass frit, the insulating material 33 is made of resin. Compared to high sealing performance. For this reason, the DSC module 100 can have excellent durability.

  In the DSC module 100, the sealing portion 30A and the insulating material 33 are arranged so as to overlap each other. For this reason, compared with the case where the insulating material 33 is arrange | positioned so that it may not overlap with 30 A of sealing parts, the area of the part which contributes to electric power generation seen from the light-receiving surface side of the DSC module 100 can be increased more. . For this reason, an aperture ratio can be improved more.

  In the DSC module 100, the first current extraction portion 12f and the second current extraction portion 12h are disposed around the DSC 50A and on the opposite side of the transparent conductive layer 12B with respect to the transparent conductive layer 12A. The first current extraction portion 12f and the second current extraction portion 12h of the transparent conductive layer 12F are arranged adjacent to each other via the groove 90. Therefore, in the DSC module 100, the external connection terminals 18a and 18b can be arranged adjacent to each of the first current extraction unit 12f and the second current extraction unit 12h. Therefore, the number of connectors for taking out current from the external connection terminals 18a and 18b to the outside can be reduced to one. That is, if the first current extraction portion 12f is disposed on the opposite side of the transparent conductive layer 12C with respect to the transparent conductive layer 12D, the first current extraction portion 12f and the second current extraction portion 12h are disposed greatly apart from each other. Therefore, the external connection terminals 18a and 18b are also arranged far apart. In this case, in order to take out the current from the DSC module 100, two connectors are required: a connector connected to the external connection terminal 18a and a connector connected to the external connection terminal 18b. However, according to the DSC module 100, since the external connection terminals 18a and 18b can be arranged adjacent to each other, only one connector is required. For this reason, according to the DSC module 100, space saving can be achieved. Further, when the DSC module 100 is used under low illuminance, the generated current is small. Specifically, the generated current is 2 mA or less. Therefore, the second current in which a part of the transparent conductive layer 12D of the DSC 50D on one end side of the DSCs 50A and 50D at both ends of the DSCs 50A to 50D is electrically connected to the metal substrate 21 of the counter electrode 20 of the DSC 50A on the other end side. Even if it arrange | positions as the 1st electric current extraction part 12f via the groove | channel 90 next to the extraction part 12h, the fall of the photoelectric conversion performance of the DSC module 100 can fully be suppressed.

  In the DSC module 100, the DSCs 50A to 50D are arranged in a line along the X direction, and the transparent conductive layer 12D of the DSC 50D on one end side of the DSCs 50A and 50D on both ends of the DSCs 50A to 50D includes the sealing portion 30A. It has a main body part 12a provided on the inner side, a first current extraction part 12f, and a connection part 12g for connecting the main body part 12a and the first current extraction part 12f. Therefore, DSC 50A and DSC 50D, which are a part of DSC 50A to 50D, are folded back halfway, and DSC 50A is used to connect two adjacent DSCs 50 to each other as compared with the case where DSC 50A and DSC 50D are arranged adjacent to each other. It becomes possible to further shorten the installation area of the connection terminals 16 provided along the arrangement direction (X direction in FIG. 2) of ˜50D, and to further reduce the space. Also, according to the DSC module 100, when the DSC module 100 is used in a low illumination environment, the generated current is usually small, so the DSC module 100 connects the main body portion 12a and the first current extraction portion 12f. Even if it has the 1st connection part 12g to perform, the fall of a photoelectric conversion characteristic can fully be suppressed.

  Further, in the DSC module 100, the current collecting wiring 17 is disposed so as not to intersect the connecting portion 14 between the back sheet 80 and the conductive substrate 15. In general, the current collector wiring 17 is porous and has air permeability, and gas such as water vapor can pass therethrough. The current collector wiring 17 is connected to the back sheet 80 and the conductive substrate 15. If it is arranged so as not to intersect the portion 14, it is possible to prevent water vapor and the like from entering the space between the back sheet 80 and the conductive substrate 15 through the current collecting wiring 17 from the outside. As a result, the DSC module 100 can have excellent durability. Moreover, since the current collection wiring 17 has resistance lower than transparent conductive layer 12D, even if a generated current becomes large, the fall of a photoelectric conversion characteristic can fully be suppressed.

  Furthermore, when the DSC module 100 is placed in an environment where the temperature change is large, the connection terminal 16 is less likely to peel from the protruding portion 12 c of the transparent conductive layer 12 as the connection terminal 16 is narrower. In that respect, in the DSC module 100, the conductive material non-connecting portion 16B of the connection terminals 16 has a narrower width than the conductive material connecting portion 16A connected to the conductive material 60P. For this reason, the conductive material non-connecting portion 16 </ b> B of the connection terminal 16 is difficult to peel off from the protruding portion 12 c of the transparent conductive layer 12. Therefore, even if the conductive material connecting portion 16A is peeled off from the protruding portion 12c of the transparent conductive layer 12, the conductive material non-connecting portion 16B is not peeled off from the transparent conductive layer 12, and the connection to the transparent conductive layer 12 can be maintained. It becomes. Even if the conductive material connecting portion 16A is peeled off from the protruding portion 12c of the transparent conductive layer 12, the DSC module 100 can operate normally. Therefore, according to the DSC module 100, connection reliability can be improved. In addition, the conductive material 60P connected to the metal substrate 21 of the counter electrode 20 in one of the two adjacent DSCs 50 is connected to the conductive material connection portion 16A on the protruding portion 12c in the other DSC 50, and the conductive material connection portion. 16A is provided outside the sealing portion 30A on the protruding portion 12c. That is, two adjacent DSCs 50 are connected to each other outside the sealing portion 30A. For this reason, according to the DSC module 100, it is possible to improve the aperture ratio.

  Further, in the DSC module 100, in the DSC 50 connected to the adjacent DSC 50 among the DSCs 50A to 50D, the projecting portion 12c extends from the main body portion 12a to the side and extends from the protruding portion 12d to the adjacent DSC 50. Of the connection terminal 16 and at least the conductive material connection portion 16A is provided on the facing portion 12e.

  In this case, since at least the conductive material connection portion 16A of the connection terminals 16 is provided on the facing portion 12e facing the main body portion 12a of the adjacent DSC 50, at least the conductive material connection portion 16A of the connection terminals 16 is Unlike the case where it is not provided on the facing portion 12e facing the main body portion 12a of the adjacent DSC 50, the conductive material 60P connected to the conductive material connecting portion 16A crosses the metal substrate 21 of the counter electrode 20 of the adjacent DSC 50. Can be sufficiently prevented. As a result, it is possible to sufficiently prevent a short circuit between adjacent DSCs 50.

  In the DSC module 100, the conductive material connecting portion 16A and the conductive material non-connecting portion 16B are both arranged along the sealing portion 30A. For this reason, compared with the case where the electrically conductive material connection part 16A and the electrically conductive material non-connection part 16B are arranged along the direction away from the sealing part 30A, the space required for the connection terminal 16 can be omitted.

  Furthermore, in the DSC module 100, the adhesive portion 80B of the back sheet 80 is separated from the sealing portion 30A of the DSC 50. For this reason, it is sufficiently suppressed that the adhesive portion 80B contracts at a low temperature to pull the sealing portion 30A and an excessive stress is applied to the interface between the sealing portion 30A and the conductive substrate 15 or the counter electrode 20. The In addition, even at a high temperature, it is sufficiently suppressed that the bonding portion 80B expands and pushes the sealing portion 30A to apply an excessive stress to the interface between the sealing portion 30A and the conductive substrate 15 or the counter electrode 20. The That is, excessive stress is sufficiently suppressed from being applied to the interface between the sealing portion 30 </ b> A and the conductive substrate 15 or the counter electrode 20 at both high and low temperatures. For this reason, the DSC module 100 can have excellent durability.

  Furthermore, in the DSC module 100, the width P of the bonding portion between the surface of the counter electrode 20 on the conductive substrate 15 side and the partition portion 31 b of the first integrated sealing portion 31 is equal to the width of the counter electrode 20 on the conductive substrate 15 side. It is narrower than the width Q of the bonding portion between the surface and the annular portion 31 a of the first integrated sealing portion 31. For this reason, the aperture ratio in the DSC module 100 can be improved more sufficiently. In the DSC module 100, the adjacent first sealing portions 31 </ b> A and the adjacent second sealing portions 32 </ b> A are integrated between the adjacent counter electrodes 20. Here, if the adjacent first sealing portions 31 </ b> A are not integrated, two adjacent sealing portions are exposed to the atmosphere between the adjacent DSCs 50. On the other hand, in the DSC module 100, since the adjacent first sealing portions 31A are integrated, there is one sealing portion exposed to the atmosphere between the adjacent DSCs 50. That is, since the 1st integrated sealing part 31 is comprised by the annular part 31a and the partition part 31b, the sealing part exposed with respect to air | atmosphere between adjacent DSC50 is the partition part 31b. There is only one place. Further, since the first sealing portions 31A are integrated with each other, the penetration distance of moisture and the like from the atmosphere to the electrolyte 40 is extended. For this reason, it is possible to sufficiently reduce the amount of moisture and air entering from the outside of the DSC 50 between the adjacent DSCs 50. That is, the sealing performance of the DSC module 100 can be sufficiently improved. Further, according to the DSC module 100, the adjacent first sealing portions 31A are integrated. For this reason, the width P of the bonding portion between the surface of the counter electrode 20 on the side of the conductive substrate 15 and the partition portion 31b of the first integrated sealing portion 31 is the same as that of the surface of the counter electrode 20 on the side of the conductive substrate 15. Even if it is narrower than the width Q of the bonding portion between the integrated sealing portion 31 and the annular portion 31a, a sufficient sealing width can be secured in the partition portion 31b. That is, according to the DSC module 100, the adhesive strength between the first sealing portion 31A and the conductive substrate 15 and the adhesive strength between the first sealing portion 31A and the counter electrode 20 are sufficiently increased while improving the aperture ratio. It becomes possible to enlarge. As a result, the aperture ratio can be improved, and when the DSC module 100 is used at a high temperature, the electrolyte 40 expands and an excessive stress is applied from the inside to the outside of the first sealing portion 31A. Also, peeling of the first sealing portion 31A from the conductive substrate 15 and the counter electrode 20 can be sufficiently suppressed, and excellent durability can be achieved.

  Furthermore, in the DSC module 100, the width R of the counter electrode 20 and the partition portion 31b of the first integrated sealing portion 31 is 100% or more and less than 200% of the width T of the annular portion 31a of the first integrated sealing portion 31. It has become. In this case, in the partition part 31b of the first integrated sealing part 31, the width of the partition part 31b is 100% or more of the width T of the annular part 31a. In comparison with the case where the width R of the partition portion 31b is less than 100% of the width T of the annular portion 31a, the penetration distance of moisture and the like from the atmosphere to the electrolyte 40 is further extended. For this reason, it can suppress more fully that a water | moisture content penetrate | invades from the exterior through the partition part 31b between adjacent DSC50. On the other hand, compared with the case where the width R of the partition part 31b exceeds 200% of the width T of the annular part 31a, the aperture ratio can be further improved.

  In the DSC module 100, the second sealing portion 32A is bonded to the first sealing portion 31A, and the edge portion 20a of the counter electrode 20 is sandwiched between the first sealing portion 31A and the second sealing portion 32A. Has been. For this reason, even if the stress in the direction away from the working electrode 10 acts on the counter electrode 20, the separation is sufficiently suppressed by the second sealing portion 32A. Further, since the partition portion 32b of the second integrated sealing portion 32 is bonded to the first sealing portion 31A through the gap S between the adjacent counter electrodes 20, the counter electrodes 20 of the adjacent DSCs 50 are in contact with each other. Is reliably prevented.

  Next, the working electrode 10, the connecting portion 14, the photosensitizing dye, the counter electrode 20, the sealing portion 30A, the electrolyte 40, the conductive materials 60P and 60Q, the back sheet 80, and the desiccant 95 will be described in detail.

(Working electrode)
The material which comprises the transparent substrate 11 should just be a transparent material, for example, As such a transparent material, glass, such as borosilicate glass, soda lime glass, white plate glass, quartz glass, polyethylene terephthalate (PET), for example , Polyethylene naphthalate (PEN), polycarbonate (PC), and polyethersulfone (PES). The thickness of the transparent substrate 11 is appropriately determined according to the size of the DSC module 100 and is not particularly limited, but may be in the range of 50 to 10,000 μm, for example.

Examples of the material contained in the transparent conductive layer 12 include tin-doped indium oxide (Indium-Tin-Oxide: ITO), tin oxide (SnO ₂ ), and fluorine-doped tin oxide (Fluorine-doped-Tin-Oxide: FTO). Examples include conductive metal oxides. The transparent conductive layer 12 may be a single layer or a laminate of a plurality of layers containing different conductive metal oxides. When the transparent conductive layer 12 is composed of a single layer, the transparent conductive layer 12 preferably includes FTO because it has high heat resistance and chemical resistance. The transparent conductive layer 12 may further include a glass frit. The thickness of the transparent conductive layer 12 may be in the range of 0.01 to 2 μm, for example.

Moreover, the resistance value of the connection part 12g of the transparent conductive layer 12D in the transparent conductive layer 12 is not particularly limited, but is preferably equal to or less than the resistance value represented by the following formula (1).
Resistance value = number of DSCs 50 connected in series × 120Ω (1)

  In this case, compared with the case where the resistance value of the connection part 12g exceeds the resistance value represented by said Formula (1), the performance fall of the DSC module 100 can fully be suppressed. In the present embodiment, since the number of DSCs 50 is 4, the resistance value represented by the above formula (1) is 480Ω, and thus the resistance value of the connecting portion 12g is preferably 480Ω or less.

  The thickness of the insulating material 33 is 10-30 micrometers normally, Preferably it is 15-25 micrometers.

  The connection terminal 16 includes metal particles. Examples of the metal material constituting the metal particles include silver, copper, and indium. You may use these individually or in combination of 2 or more types.

  The shape of the metal particles is not particularly limited, but examples of the shape of the metal particles include a spherical shape and a scale shape. Of these, the shape of the metal particles is preferably spherical. In this case, the adhesion between the transparent conductive layer 12 or the conductive material 60P and the connection terminal 16 is further improved.

  Gaps are formed between the metal particles contained in the connection terminals 16. As shown in FIG. 8, the non-conductive region ratio T, which is the ratio of the area T2 of the non-conductive region 98c excluding the metal particles 98b from the observation region 98a in the total area T1 of the observation region 98a in the cross section of the connection terminal 16. Although it does not specifically limit, Preferably it is 10-50 area%, More preferably, it is 15-40 area%. Here, the area T2 of the nonconductive region 98c obtained by removing the metal particles 98b from the observation region 98a represents the area of the gap.

  In the connection terminal 16, the width of the conductive material non-connecting portion 16B is not particularly limited as long as it is smaller than the width of the conductive material connecting portion 16A, but is preferably 1/2 or less of the width of the conductive material connecting portion 16A.

  In this case, the connection reliability in the DSC module 100 can be further improved as compared with the case where the width of the conductive material non-connecting portion 16B exceeds 1/2 of the width of the conductive material connecting portion 16A.

  The width of the conductive material connecting portion 16A is not particularly limited, but is preferably 0.5 to 5 mm, and more preferably 0.8 to 2 mm.

The oxide semiconductor layer 13 is composed of oxide semiconductor particles. Examples of such oxide semiconductor particles include titanium oxide (TiO ₂ ), silicon oxide (SiO ₂ ), zinc oxide (ZnO), tungsten oxide (WO ₃ ), niobium oxide (Nb ₂ O ₅ ), and strontium titanate. (SrTiO ₃ ), tin oxide (SnO ₂ ), indium oxide (In ₃ O ₃ ), zirconium oxide (ZrO ₂ ), thallium oxide (Ta ₂ O ₅ ), lanthanum oxide (La ₂ O ₃ ), yttrium oxide (Y ₂ O ₃ ), holmium oxide (Ho ₂ O ₃ ), bismuth oxide (Bi ₂ O ₃ ), cerium oxide (CeO ₂ ) and aluminum oxide (Al ₂ O ₃ ). These can be used alone or in combination of two or more.

(Connecting part)
The material constituting the connecting portion 14 is not particularly limited as long as the back sheet 80 and the transparent conductive layer 12 can be bonded. Examples of the material constituting the connecting portion 14 include glass frit and sealing portion. A resin material similar to the resin material used for 31A can be used. Especially, it is preferable that the connection part 14 is a glass frit. Since the glass frit has a higher sealing performance than the resin material, it is possible to effectively suppress intrusion of moisture and the like from the outside of the back sheet 80.

(Photosensitizing dye)
Examples of the photosensitizing dye include a ruthenium complex having a ligand containing a bipyridine structure, a terpyridine structure, and the like, and organic dyes such as porphyrin, eosin, rhodamine, and merocyanine.

(Counter electrode)
As described above, the counter electrode 20 includes the metal substrate 21 and the conductive catalyst layer 22 that is provided on the working electrode 10 side of the metal substrate 21 and promotes the reduction reaction on the surface of the counter electrode 20.

  The metal substrate 21 is made of a corrosion-resistant metal material such as titanium, nickel, platinum, molybdenum, tungsten, aluminum, and stainless steel. The thickness of the metal substrate 21 is appropriately determined according to the size of the DSC module 100 and is not particularly limited, but may be, for example, 0.005 to 0.1 mm.

  The catalyst layer 22 is composed of platinum, a carbon-based material, a conductive polymer, or the like. Here, carbon nanotubes are suitably used as the carbon-based material.

(Sealing part)
The sealing unit 30A includes a first sealing unit 31A and a second sealing unit 32A.

  Examples of the material constituting the first sealing portion 31A include a modified polyolefin resin containing, for example, an ionomer, an ethylene-vinyl acetic anhydride copolymer, an ethylene-methacrylic acid copolymer, an ethylene-vinyl alcohol copolymer, and ultraviolet curing. Examples thereof include resins and resins such as vinyl alcohol polymers.

  The thickness of 31A of 1st sealing parts is 40-90 micrometers normally, Preferably it is 60-80 micrometers.

  The width P of the bonded portion between the counter electrode 20 and the partition portion 31b is preferably 25% or more and less than 100% of the width Q of the bonded portion between the counter electrode 20 and the annular portion 31a of the first integrated sealing portion 31. In this case, compared with the case where the width | variety P of an adhesion part is less than 25% of the width | variety Q of an adhesion part, it becomes possible to have more outstanding durability. The width P of the bonding portion is more preferably 30% or more of the width Q of the bonding portion, and further preferably 40% or more.

  In the DSC module 100, the width R of the partition part 31b of the first integrated sealing part 31 is preferably 100% or more and less than 200% of the width T of the annular part 31a of the first integrated sealing part 31. 120 to 180% is more preferable.

  In this case, a large aperture ratio and excellent durability can be balanced.

  As the material constituting the second sealing portion 32A, for example, an ionomer, an ethylene-vinyl acetic anhydride copolymer, an ethylene-methacrylic acid copolymer, an ethylene-vinyl alcohol copolymer, as in the first sealing portion 31A. Examples thereof include resins such as modified polyolefin resins, UV curable resins, and vinyl alcohol polymers. The material constituting the second sealing portion 32A is preferably the same as the material constituting the first sealing portion 31A. In this case, since the interface between the second sealing portion 32A and the first sealing portion 31A is eliminated, it is possible to effectively suppress the intrusion of moisture from the outside and the leakage of the electrolyte 40.

  The thickness of the second sealing portion 32A is usually 20 to 45 μm, preferably 30 to 40 μm.

(Electrolytes)
The electrolyte 40 contains a redox couple such as I ⁻ / I ₃ ^— and an organic solvent. As an organic solvent, acetonitrile, methoxyacetonitrile, methoxypropionitrile, propionitrile, ethylene carbonate, propylene carbonate, diethyl carbonate, γ-butyrolactone, valeronitrile, pivalonitrile, glutaronitrile, methacrylonitrile, isobutyronitrile, Phenylacetonitrile, acrylonitrile, succinonitrile, oxalonitrile, pentanitrile, adiponitrile and the like can be used. Examples of the redox pair include redox pairs such as bromine / bromide ions, zinc complexes, iron complexes, and cobalt complexes in addition to I ⁻ / I ₃ ^— .

  The electrolyte 40 may use an ionic liquid instead of the organic solvent. As the ionic liquid, for example, a known iodine salt such as a pyridinium salt, an imidazolium salt, or a triazolium salt, and a room temperature molten salt that is in a molten state near room temperature is used. Examples of such room temperature molten salts include 1-hexyl-3-methylimidazolium iodide, 1-ethyl-3-propylimidazolium iodide, dimethylimidazolium iodide, ethylmethylimidazolium iodide, and dimethylpropyl. Imidazolium iodide, butylmethylimidazolium iodide, or methylpropylimidazolium iodide is preferably used.

  In addition, the electrolyte 40 may use a mixture of the ionic liquid and the organic solvent instead of the organic solvent.

An additive can be added to the electrolyte 40. As the _{additive, LiI, I 2, 4-} t- butylpyridine, guanidinium thiocyanate, 1-methylbenzimidazole, 1-butyl-benzimidazole and the like.

Further, as the electrolyte 40, a nano-composite gel electrolyte, which is a pseudo-solid electrolyte formed by kneading nanoparticles such as SiO ₂ , TiO ₂ , carbon nanotubes, etc. into the electrolyte, may be used, and polyvinylidene fluoride may be used. Alternatively, an electrolyte gelled with an organic gelling agent such as a polyethylene oxide derivative or an amino acid derivative may be used.

The electrolyte 40 includes an oxidation-reduction pair consisting of I ⁻ / I ₃ ^—, and the concentration of I ₃ ⁻ is preferably 0.006 mol / liter or less, and is 0 to 6 × 10 ⁻⁶ mol / liter. More preferably, it is more preferably 0-6 × 10 ⁻⁸ mol / liter. In this case, since the concentration of I ₃ ⁻ carrying electrons is low, the leakage current can be further reduced. For this reason, since an open circuit voltage can be increased more, a photoelectric conversion characteristic can be improved more.

(Conductive material)
The conductive materials 60P and 60Q include metal particles and a binder resin.

  As the metal material constituting the metal particles, for example, silver, gold, copper, nickel, platinum, palladium or the like can be used.

  Although the average particle diameter of a metal particle is not specifically limited, Preferably it is 0.1-20 micrometers, More preferably, it is 2-10 micrometers. When the average particle diameter of the metal particles is within the above range, the adhesion between the counter electrode 20 and the metal substrate 21 is further improved or the conductivity is further improved as compared with a case outside the above range.

  The shape of the metal particles is not particularly limited, but examples of the shape of the metal particles include a spherical shape and a scale shape. Of these, the shape of the metal particles is preferably scaly. In this case, the stress applied to the conductive material 60P is easily relaxed, and even when the stress is relaxed, the conductivity is difficult to decrease. In particular, when the shape of the metal particles contained in the connection terminal 16 is spherical, the shape of the metal particles of the conductive material 60P is preferably scaly. In this case, the metal particles contained in the connection terminal 16 are spherical, thereby ensuring sufficient adhesion between the transparent conductive layer 12 and the connection terminal 16 and adhesion between the connection terminal 16 and the conductive material 60P. On the other hand, the shape of the metal particles contained in the conductive material 60P is scaly, so that the stress applied to the conductive material 60P is more sufficiently relaxed, and the conductivity when the stress is relaxed is more sufficiently maintained. Can do.

  The aspect ratio of the scale-like metal particles is not particularly limited, but is preferably 1: 2 to 1:30. Here, the scale-like metal particles have a pair of main surfaces, and the aspect ratio is the thickness of the metal particles (distance between the pair of main surfaces) when the cross section of the conductive material 60P is observed with an SEM. The ratio of the length of the longest line segment among the line segments connecting the two intersections of the annular line forming the main surface and the line crossing the main surface shall be said.

  Examples of the binder resin include polyester resin, acrylic resin, phenol resin, vinyl chloride vinyl acetate copolymer resin, urethane resin, epoxy resin, and cellulose resin. These can be used alone or in combination of two or more.

  The non-conductive region ratio S in the observation region 97a of the cross section of the conductive materials 60P and 60Q is preferably 40 to 60 area%. In this case, compared to the case where the non-conductive region ratio S is out of the above range, the stress due to expansion or contraction can be further relaxed, and the durability is further improved.

  The metal particles contained in the conductive material 60P may be made of the same metal as or different from the metal particles contained in the connection terminal 16, but may be made of the same metal. preferable.

  In this case, since the metal particles contained in the connection terminal 16 and the conductive material 60P are made of the same metal, compared to the case where the metal particles contained in the connection terminal 16 and the conductive material 60P are made of different metals, The adhesion between the connection terminal 16 and the conductive material 60P can be more sufficiently improved. For this reason, the connection reliability in the DSC module 100 can be further improved.

  The non-conductive region ratio S in the conductive material 60P may be larger than the non-conductive region ratio T in the connection terminal 16 or may be equal to or less than the non-conductive region ratio T in the connection terminal 16. It is preferable that the ratio is larger than T. In this case, the adhesive strength between the connection terminal 16 and the transparent conductive layer 12 is greater than the case where the non-conductive region ratio S in the conductive material 60P is equal to or less than the non-conductive region ratio T in the connection terminal 16, or The contact resistance with the conductive layer 12 may become smaller.

(Back sheet)
As described above, the back sheet 80 is provided on the surface of the laminate 80A including the weather resistant layer and the metal layer, and the DSC 50 side of the laminate 80A, and bonds the laminate 80A and the connecting portion 14 together. 80B.

  The weather resistant layer may be made of, for example, polyethylene terephthalate or polybutylene terephthalate.

  The thickness of the weather resistant layer may be, for example, 50 to 300 μm.

  The metal layer should just be comprised with the metal material containing aluminum, for example. The metal material is usually composed of aluminum alone, but may be an alloy of aluminum and another metal. Examples of other metals include copper, manganese, zinc, magnesium, lead, and bismuth. Specifically, 1000 series aluminum obtained by adding a trace amount of other metals to 98% or more pure aluminum is desirable. This is because the 1000 series aluminum is cheaper and more workable than other aluminum alloys.

  Although the thickness of a metal layer is not specifically limited, For example, what is necessary is just 12-30 micrometers.

  The stacked body 80A may further include a resin layer. Examples of the material constituting the resin layer include butyl rubber, nitrile rubber, thermoplastic resin, and the like. These can be used alone or in combination of two or more. The resin layer may be formed on the entire surface of the metal layer opposite to the weather-resistant layer, or may be formed only on the peripheral edge.

  Examples of the material constituting the bonding portion 80B include butyl rubber, nitrile rubber, and thermoplastic resin. These can be used alone or in combination of two or more. The thickness of the bonding portion 80B is not particularly limited, but may be, for example, 300 to 1000 μm.

(desiccant)
The desiccant 95 may be a sheet or a granule. The desiccant 95 only needs to absorb moisture, for example, and examples of the desiccant 95 include silica gel, alumina, and zeolite.

  Next, a method for manufacturing the DSC module 100 will be described with reference to FIGS. 3, 9 and 10. 10 is a plan view showing a first integrated sealing portion forming body for forming the first integrated sealing portion of FIG.

  First, a laminate in which a transparent conductive layer is formed on one transparent substrate 11 is prepared.

  As a method for forming the transparent conductive layer, sputtering, vapor deposition, spray pyrolysis (SPD), CVD, or the like is used.

  Next, as shown in FIG. 3, grooves 90 are formed in the transparent conductive layer, and transparent conductive layers 12 </ b> A to 12 </ b> F arranged in an insulated state with the grooves 90 interposed therebetween are formed. Specifically, the four transparent conductive layers 12A to 12D corresponding to the DSCs 50A to 50D are formed so as to have a rectangular main body 12a and protrusions 12c. At this time, with respect to the transparent conductive layers 12A to 12C corresponding to the DSCs 50A to 50C, the projecting portion 12c extends not only from the overhanging portion 12d but also from the overhanging portion 12d to form a facing portion 12e facing the main body portion 12a of the adjacent DSC 50. Also formed to have The transparent conductive layer 12D includes not only the rectangular main body 12a and the overhanging portion 12d, but also the first current extraction portion 12f and a connection portion 12g that connects the first current extraction portion 12f and the main body portion 12a. To form. At this time, the first current extraction portion 12f is formed to be disposed on the opposite side of the transparent conductive layer 12B with respect to the transparent conductive layer 12A. Further, the transparent conductive layer 12E is formed so that the second current extraction portion 12h is formed. At this time, the second current extraction portion 12h is disposed on the opposite side of the transparent conductive layer 12B with respect to the transparent conductive layer 12A, and is disposed adjacent to the first current extraction portion 12f via the groove 90. Form.

The groove 90 can be formed by a laser scribing method using, for example, a YAG laser or a CO ₂ laser as a light source.

  Thus, the transparent conductive layer 12 is formed on the transparent substrate 11.

  Next, a precursor of the connection terminal 16 composed of the conductive material connection portion 16A and the conductive material non-connection portion 16B is formed on the protruding portion 12c of the transparent conductive layers 12A to 12C. Specifically, the precursor of the connection terminal 16 is formed so that the conductive material connection portion 16A is provided on the facing portion 12e. Further, the precursor of the connection terminal 16 is also formed on the transparent conductive layer 12E. The precursor of the conductive material non-connecting portion 16B is formed to be narrower than the width of the conductive material connecting portion 16A. The precursor of the connection terminal 16 can be formed, for example, by applying a silver paste and drying it.

  Furthermore, the precursor of the current collection wiring 17 is formed on the connection part 12g of transparent conductive layer 12D. The precursor of the current collecting wiring 17 can be formed, for example, by applying a silver paste and drying it.

  Also, precursors for external connection terminals 18a and 18b for taking out current to the outside are formed on the first current extraction portion 12f and the second current extraction portion 12h of the transparent conductive layer 12A, respectively. The precursor of the terminal for external connection can be formed, for example, by applying a silver paste and drying it.

  Further, the precursor of the insulating material 33 made of glass frit is formed so as to enter the first groove 90A formed along the edge of the main body 12a and also cover the edge of the main body 12a. The insulating material 33 can be formed, for example, by applying and drying a paste containing glass frit.

  In addition, in order to fix the backsheet 80, the annular connecting portion 14 is surrounded by the transparent conductive layer 12D, the transparent conductive layer 12E, and the transparent conductive layer 12F so as to surround the insulating material 33 in the same manner as the insulating material 33. A precursor is formed.

  Further, a precursor of the oxide semiconductor layer 13 is formed on the main body portion 12a of each of the transparent conductive layers 12A to 12D.

  The precursor of the oxide semiconductor layer 13 is obtained by printing and drying an oxide semiconductor layer forming paste for forming the oxide semiconductor layer 13. The oxide semiconductor layer forming paste includes a resin such as polyethylene glycol and ethyl cellulose, and a solvent such as terpineol, in addition to the oxide semiconductor particles.

  As a method for printing the oxide semiconductor layer forming paste, for example, a screen printing method, a doctor blade method, a bar coating method, or the like can be used.

  Finally, the precursor of the connection terminal 16, the precursor of the insulating material 33, the precursor of the connecting portion 14, and the precursor of the oxide semiconductor layer 13 are baked together to form the connecting terminal 16, the insulating material 33, and the connecting portion 14. And the oxide semiconductor layer 13 are formed.

  At this time, the firing temperature varies depending on the types of oxide semiconductor particles and glass frit, but is usually 350 to 600 ° C., and the firing time also varies depending on the types of oxide semiconductor particles and glass frit, but usually 1 to 5 times. It's time.

  Thus, as shown in FIG. 9, the connecting portion 14 for fixing the back sheet 80 is formed, and the working electrode 10 having the conductive substrate 15 is obtained.

  Next, a photosensitizing dye is supported on the oxide semiconductor layer 13 of the working electrode 10. For this purpose, the working electrode 10 is immersed in a solution containing a photosensitizing dye, the photosensitizing dye is adsorbed on the oxide semiconductor layer 13, and then the excess photosensitizer is added with the solvent component of the solution. The photosensitizing dye may be adsorbed to the oxide semiconductor layer 13 by washing away the dye and drying it. However, even if the photosensitizing dye is adsorbed to the oxide semiconductor layer 13 by applying a solution containing the photosensitizing dye to the oxide semiconductor layer 13 and then drying the solution, the photosensitizing dye can be absorbed into the oxide semiconductor layer 13. 13 can be carried.

  Next, the electrolyte 40 is disposed on the oxide semiconductor layer 13.

  Next, as shown in FIG. 10, a first integrated sealing portion forming body 131 for forming the first integrated sealing portion 31 is prepared. The first integrated sealing portion forming body 131 prepares one sealing resin film made of the material constituting the first integrated sealing portion 31, and the sealing resin film according to the number of DSCs 50. It can be obtained by forming a rectangular opening 131a. The first integrated sealing portion forming body 131 has a structure in which a plurality of first sealing portion forming bodies 131A are integrated.

  Then, the first integrated sealing portion forming body 131 is bonded onto the conductive substrate 15. At this time, the first integrated sealing portion forming body 131 is bonded so as to overlap the insulating material 33. The adhesion of the first integrated sealing portion forming body 131 to the conductive substrate 15 can be performed by heating and melting the first integrated sealing portion forming body 131. The first integrated sealing portion forming body 131 is bonded to the conductive substrate 15 so that the main body portion 12 a of the transparent conductive layer 12 is disposed inside the first integrated sealing portion forming body 131.

  On the other hand, the same number of counter electrodes 20 as the number of DSCs 50 are prepared.

  The counter electrode 20 can be obtained by forming a conductive catalyst layer 22 that promotes the reduction reaction on the surface of the counter electrode 20 on the metal substrate 21.

  Next, another first integrated sealing portion forming body 131 described above is prepared. And each of the some counter electrode 20 is bonded together so that each opening 131a of the 1st integrated sealing part formation body 131 may be plugged up.

  Next, the first integrated sealing portion forming body 131 bonded to the counter electrode 20 and the first integrated sealing portion forming body 131 bonded to the working electrode 10 are superposed to form a first integrated sealing portion forming body. 131 is heated and melted under pressure. Thus, the first integrated sealing portion 31 is formed between the working electrode 10 and the counter electrode 20. At this time, the width P of the bonding portion between the surface of the counter electrode 20 on the conductive substrate 15 side and the partition portion 31b of the first integrated sealing portion 31 is equal to the surface of the counter electrode 20 on the conductive substrate 15 side. The 1st integrated sealing part 31 is formed so that it may become narrower than the width | variety Q of the adhesion part with the annular part 31a of the integrated sealing part 31. FIG. Further, the first integrated sealing is performed such that the width R of the partition portion 31b of the first integrated sealing portion 31 is not less than 100% and less than 200% of the width T of the annular portion 31a of the first integrated sealing portion 31. A portion 31 is formed. The formation of the first integrated sealing portion 31 may be performed under atmospheric pressure or under reduced pressure, but is preferably performed under reduced pressure.

  Next, the 2nd integrated sealing part 32 is prepared (refer FIG. 6). The second integrated sealing portion 32 has a structure formed by integrating a plurality of first sealing portions 32A. The second integrated sealing portion 32 can be obtained by preparing a single sealing resin film and forming the rectangular openings 32c corresponding to the number of DSCs 50 in the sealing resin film. The second integrated sealing portion 32 is bonded to the counter electrode 20 so as to sandwich the edge portion 20 a of the counter electrode 20 together with the first integrated sealing portion 31. The adhesion of the second integrated sealing portion 32 to the counter electrode 20 can be performed by heating and melting the second integrated sealing portion 32.

  Examples of the sealing resin film include ionomers, ethylene-vinyl acetic anhydride copolymers, modified polyolefin resins containing ethylene-methacrylic acid copolymers, ethylene-vinyl alcohol copolymers, ultraviolet curable resins, and vinyls. Examples thereof include resins such as alcohol polymers. The constituent material of the sealing resin film for forming the second integrated sealing portion 32 has a higher melting point than the constituent material of the sealing resin film for forming the first integrated sealing portion 31. It is preferable. In this case, since the second sealing portion 32A is harder than the first sealing portion 31A, it is possible to effectively prevent contact between the counter electrodes 20 of the adjacent DSCs 50. In addition, since the first sealing portion 31A is softer than the second sealing portion 32A, the stress applied to the sealing portion 30A can be effectively relieved.

  Next, the bypass diodes 70 </ b> A, 70 </ b> B, and 70 </ b> C are fixed to the partition part 32 b of the second sealing part 32. The bypass diode 70D is also fixed on the sealing portion 30A of the DSC 50D.

  Then, the conductive material 60Q is fixed to the metal substrate 21 of the counter electrode 20 of the DSCs 50B to 50C so as to pass through the bypass diodes 70A to 70D. Further, between the bypass diodes 70A and 70B, between the bypass diodes 70B and 70C, between the bypass diodes 70C and 70D, the conductive material connecting portion 16A on the transparent conductive layer 12A, and the conductive material connecting portion on the transparent conductive layer 12B. A conductive material 60P is formed so as to connect 16A and the conductive material connecting portion 16A on the transparent conductive layer 12C. Further, the conductive material 60P is fixed to the metal substrate 21 of the counter electrode 20 of the DSC 50A so as to connect the conductive material connecting portion 16A on the transparent conductive layer 12E and the bypass diode 70A. Further, the transparent conductive layer 12D and the bypass diode 70A are connected by the conductive material 60P.

  At this time, as the conductive material 60P, a conductive paste containing metal particles, a binder resin, and an organic solvent is prepared. After the conductive paste is stirred, for example, by a planetary mixer, the conductive material 60P is electrically connected to the connection terminal 16 of the adjacent DSC 50 from the counter electrode 20. It can be obtained by applying over the material connecting portion 16A, drying and curing. For example, the conductive material 60Q is stirred with a planetary mixer, and then a conductive paste containing metal particles, a binder resin, and an organic solvent is prepared, and this conductive paste is applied so as to connect adjacent bypass diodes on each counter electrode 20. It can be obtained by drying and curing. At this time, air can be included in the conductive paste by stirring with a planetary mixer before applying the conductive paste. The curing temperature may be a temperature at which the binder resin does not decompose and disappear. Specifically, the curing temperature is preferably 90 ° C. or lower from the viewpoint of avoiding adverse effects on the photosensitizing dye. As said organic solvent, it is preferable to use what has a boiling point of 120 degrees C or less. Examples of the organic solvent having a boiling point of 120 ° C. or lower include toluene, acetone and 1-propanol.

  The conductive paste preferably contains 40-80% by mass of metal particles, 5-20% by mass of a binder resin, and 10-50% by mass of an organic solvent.

  In this case, compared to the case where the content ratio of the metal particles and the binder resin is out of the above range, the obtained conductive materials 60P and 60Q are less likely to be peeled off from the metal substrate 21 of the counter electrode 20, or the conductivity of the conductive materials 60P and 60Q. May be improved or it will be easier to apply the paste.

  Finally, a back sheet 80 is prepared, and the peripheral edge 80 a of the back sheet 80 is bonded to the connecting portion 14. At this time, the back sheet 80 is disposed so that the adhesive portion 80B of the back sheet 80 and the sealing portion 30A of the DSC 50 are separated from each other.

  The DSC module 100 is obtained as described above.

  In the above description, in order to form the connection terminal 16, the insulating material 33, the connecting portion 14, and the oxide semiconductor layer 13, the precursor of the connecting terminal 16, the precursor of the insulating material 33, and the precursor of the connecting portion 14. Body, the precursor of the oxide semiconductor layer 13 is baked in a lump, but the connection terminal 16, the insulating material 33, the connecting portion 14, and the oxide semiconductor layer 13 are separately fired. May be formed.

  The present invention is not limited to the above embodiment. For example, in the above-described embodiment, the DSCs 50A to 50D are arranged in a line along the X direction in FIG. 2, but like the DSC module 200 shown in FIG. The DSC 50A and the DSC 50D may be arranged so that they are adjacent to each other. In this case, unlike the DSC module 100, the transparent conductive layer 12D does not require the connection portion 12g to be provided between the main body portion 12a and the first current extraction portion 12f. For this reason, it is not necessary to provide the current collection wiring 17 either.

  Moreover, in the said embodiment, although the 2nd groove | channel 90B which cross | intersects the connection part 14 of the back seat | sheet 80 and the electroconductive board | substrate 15 is not covered with the insulating material 33 which consists of glass frit, the DSC module 300 shown in FIG. As described above, the second groove 90B is preferably covered with an insulating material 33 made of glass frit. In FIG. 12, the back sheet 80 is omitted. As shown in FIG. 12, when the second groove 90 </ b> B intersects the connecting portion 14, moisture may enter the space between the back sheet 80 and the conductive substrate 15 through the second groove 90 </ b> B. It becomes possible. In this case, the insulating material 33 enters the second groove 90 </ b> B, and the insulating material 33 also covers the edge of the transparent conductive layer 12 except for the main body portion 12 a, so that the back sheet 80 is inward from the outside. Moisture penetration into the water is sufficiently suppressed. For this reason, the water | moisture content which penetrate | invaded into the space between the backsheet 80 and the electroconductive board | substrate 15 fully suppresses entering the inside of 30 A of sealing parts through 30 A of sealing parts. For this reason, it is possible to sufficiently suppress a decrease in durability of the DSC module 300.

Furthermore, in the said embodiment, although the 1st electric current extraction part 12f and the 2nd electric current extraction part 12h are arrange | positioned around the DSC50A side, as shown to the DSC module 400 shown in FIG. And the 2nd electric current extraction part 12h may be arrange | positioned around the DSC50D side. In this case, the first current extraction portion 12f is provided so as to protrude to the outside of the sealing portion 30A on the side opposite to the DSC 50C with respect to the main body portion 12a of the transparent conductive layer 12D. On the other hand, the second current extraction portion 12h is provided on the opposite side of the DSC 50C with respect to the main body portion 12a of the transparent conductive layer 12D. A connecting portion 12i as a second connecting portion extends along the transparent conductive layers 12A to 12D, and the connecting portion 12i connects the second current extraction portion 12f and the metal substrate 21 of the counter electrode 20 of the DSC 50A. Yes. Specifically, the current collection wiring 417 is provided on the connection portion 12i along the connection portion 12i, and the current collection wiring 417 and the conductive material 60P extending from the bypass diode 70A are connected. The DSC module 400 can also save space while having excellent photoelectric conversion characteristics. In this case, the resistance value of the connection portion 12i is preferably equal to or less than the resistance value represented by the following formula (1), as in the above embodiment.
Resistance value = number of DSCs 50 connected in series × 120Ω (1)

  Moreover, in the said embodiment, although the electroconductive board | substrate 15 has the insulating material 33, it does not need to have the insulating material 33. FIG. In this case, the sealing portion 30 </ b> A and the first integrated sealing portion 31 </ b> A are joined to the transparent substrate 11, the transparent conductive layer 12, or the connection terminal 16. Here, the conductive substrate 15 may not have the connection terminal 16. In this case, the sealing portion 30 </ b> A and the first integrated sealing portion 31 </ b> A are joined to the transparent substrate 11 or the transparent conductive layer 12.

  Moreover, in the said embodiment, although the groove | channel 90 has the 2nd groove | channel 90B, the 2nd groove | channel 90B does not necessarily need to be formed.

  Moreover, in the said embodiment, although the width | variety of the conductive material connection part 16A and the conductive material non-connection part 16B of the connection terminal 16 is made constant, the width | variety of the conductive material connection part 16A and the conductive material non-connection part 16B is respectively connected. It may change along the extending direction of the terminal 16. For example, the width of the conductive material non-connecting portion 16B monotonically increases from the end farthest from the conductive material connecting portion 16A toward the end closest to the conductive material connecting portion 16A. The width may monotonously increase from the end portion on the 16B side toward the end portion farthest from the conductive material non-connecting portion 16B.

  Moreover, in the said embodiment, although the electrically-conductive material connection part 16A and the electrically-conductive material non-connection part 16B are provided along the sealing part 30A, respectively, these are formed so that it may extend in the direction away from the sealing part 30A. May be. However, in this case, it is preferable that the conductive material connecting portion 16A is disposed at a position closer to the sealing portion 30A than the conductive material non-connecting portion 16B. In this case, the conductive material 60P can be made shorter.

  Alternatively, in the connection terminals 16 formed on the transparent conductive layers 12A to 12C, the conductive material non-connecting portion 16B may be arranged to be orthogonal to the conductive material connecting portion 16A.

  Further, it may be equal to or smaller than the width of the conductive material connecting portion 16A and the conductive material non-connecting portion 16B.

  In the above embodiment, the second sealing portion 32A is bonded to the first sealing portion 31A. However, the second sealing portion 32A may not be bonded to the first sealing portion 31A.

  Furthermore, in the said embodiment, although 30 A of sealing parts are comprised by 31 A of 1st sealing parts and 32 A of 2nd sealing parts, 32 A of 2nd sealing parts may be abbreviate | omitted.

  Moreover, in the said embodiment, the width P of the adhesion part of the counter electrode 20 and the partition part 31b of the 1st integrated sealing part 31 is the adhesion part of the counter electrode 20 and the annular part 31a of the 1st integrated sealing part 31. Although it is narrower than the width Q, the width P of the bonding portion may be equal to or greater than the width Q of the bonding portion.

  Furthermore, in the said embodiment, the width | variety R of the partition part 31b of the 1st integrated sealing part 31 is 100% or more of the width | variety T of the annular part 31a of the 1st integrated sealing part 31, and less than 200%. However, the width R of the partition part 31b may be less than 100% of the width T of the annular part 31a of the first integrated sealing part 31, or 200% or more.

  In the above embodiment, the back sheet 80 and the transparent conductive layer 12 are bonded via the connecting portion 14 made of glass frit. However, the back sheet 80 and the transparent conductive layer 12 are not necessarily connected via the connecting portion 14. Need not be glued together.

  Furthermore, in the said embodiment, although the connection part 14 and the insulating material 33 are spaced apart, it is preferable that these are all comprised and integrated with the glass frit. In this case, even if moisture enters in the space between the back sheet 80 and the conductive substrate 15, the interface between the connecting portion 14 and the conductive substrate 15, between the sealing portion 30 </ b> A and the conductive substrate 15. No interface exists. Further, both the insulating material 33 and the connecting portion 14 are made of glass frit, and have higher sealing performance than that of resin. For this reason, the penetration | invasion of the water | moisture content through the interface between the connection part 14 and the electroconductive board | substrate 15 and the interface between the insulating material 33 and the electroconductive board | substrate 15 can fully be suppressed.

  Moreover, in the said embodiment, although the insulating material 33 consists of glass frit, the material which comprises the insulating material 33 should just have melting | fusing point higher than the material which comprises 30 A of 1st sealing parts. For this reason, examples of such a material include glass frit, thermosetting resins such as polyimide resins, and thermoplastic resins. Among these, it is preferable to use a thermosetting resin. In this case, even if the sealing portion 30A becomes fluid at high temperatures, the insulating material 33 is less likely to be fluidized at high temperatures than when it is made of a thermoplastic resin, as in the case of glass frit. For this reason, the contact between the conductive substrate 15 and the counter electrode 20 is sufficiently suppressed, and a short circuit between the conductive substrate 15 and the counter electrode 20 can be sufficiently suppressed.

  Furthermore, in the said embodiment, although several DSC50 is connected in series, you may connect in parallel.

  Further, in the above embodiment, a plurality of DSCs 50 are used. However, in the present invention, only one DSC 50 may be used like the dye-sensitized solar cell element 500 shown in FIG. In the dye-sensitized solar cell element 500 shown in FIG. 14, DSC 50 </ b> A to DSC 50 </ b> C are omitted, and the connection terminal 16 provided on the transparent conductive layer 12 </ b> E that does not constitute part of the DSC 50 and the metal substrate of the counter electrode 20 of the DSC 50 </ b> D. 21 is electrically connected through a conductive material 60P. Further, in the dye-sensitized solar cell element 500, the connection terminal 16 includes only the conductive material connection portion 16A, and the conductive material connection portion 16A is disposed between the sealing portion 30A and the coupling portion 14. That is, the conductive material connecting portion 16A is not disposed at a position facing the side edge portion 12b of the main body portion 12a in the transparent conductive film 12D of the DSC 50D. For this reason, in the DSC module 100 of the first embodiment, the oxide semiconductor layer 13 can be expanded to the space where the conductive material connecting portion 16A is disposed. In this case, a useless space is effectively used and the power generation area can be expanded.

  Moreover, in the said embodiment, although the number of DSC50 is four, what is necessary is just one or more, and is not limited to four. When there are a plurality of DSCs 50 as described above, it is preferable to arrange the DSCs 50 in a certain direction as shown in FIG. 2 rather than when a part of the DSCs 50A to 50D is turned back halfway as shown in FIG. When the DSCs 50 are arranged in a certain direction as described above, it is possible to select either an even number or an odd number as the number of DSCs 50, the number of DSCs 50 can be freely determined, and the degree of freedom in design is improved. be able to.

  Moreover, in the said embodiment, although the electrically conductive materials 60P and 60Q contain the space | gap, the electrically conductive materials 60P and 60Q do not need to have a space | gap.

  Hereinafter, the content of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

Example 1
First, a laminated body (trade name “TEC15”, manufactured by Pilkington Co., Ltd.) having a thickness of 2.2 mm formed by forming a transparent conductive layer made of FTO on a transparent substrate made of glass was prepared. Next, as shown in FIG. 3, CO to form a groove 90 on the transparent conductive layer 12 by ₂ laser (Universal System Co. V-460), to form a transparent conductive layer 12A-12F. At this time, the width of the groove 90 was 1 mm. Each of the transparent conductive layers 12A to 12C was formed so as to have a rectangular main body portion of 4.6 cm × 2.0 cm and a protruding portion protruding from one side edge portion of the main body portion. The transparent conductive layer 12D was formed to have a 4.6 cm × 2.1 cm rectangular main body and a protruding portion protruding from one side edge of the main body. Further, of the transparent conductive layers 12A to 12D, the projecting portions 12c of the three transparent conductive layers 12A to 12C are extended from the one side edge portion 12b of the main body portion 12a and the protruding portion 12d, and are adjacent to the transparent portion. The conductive layer 12 is composed of a facing portion 12e facing the main body portion 12a. Further, the protruding portion 12c of the transparent conductive layer 12D is configured only by the overhanging portion 12d protruding from the one side edge portion 12b of the main body portion 12a. At this time, the length of the overhang portion 12d in the overhang direction (direction orthogonal to the X direction in FIG. 2) was 2.1 mm, and the width of the overhang portion 12d was 9.8 mm. The width of the facing portion 12e was 2.1 mm, and the length of the facing portion 12e in the extending direction was 9.8 mm.

  Further, the transparent conductive layer 12D is formed so as to have not only the main body portion 12a and the protruding portion 12c but also the first current extraction portion 12f and the connection portion 12g that connects the first current extraction portion 12f and the main body portion 12a. did. The transparent conductive layer 12E was formed to have the second current extraction portion 12h. At this time, the width of the connecting portion 12g was 1.3 mm, and the length was 59 mm. Further, the resistance value of the connecting portion 12g was measured by a four-terminal method and found to be 100Ω.

  Next, the precursor of the connection terminal 16 composed of the conductive material connecting portion 16A and the conductive material non-connecting portion 16B was formed on the protruding portion 12c of the transparent conductive layers 12A to 12C. Specifically, the precursor of the connection terminal 16 is provided such that the precursor of the conductive material non-connecting portion 16B is provided on the overhanging portion 12d so that the precursor of the conductive material connecting portion 16A is provided on the facing portion 12e. Formed. At this time, the precursor of the conductive material non-connecting portion 16B was formed to be narrower than the width of the conductive material connecting portion 16A. The precursor of the connection terminal 16 was formed by applying and drying a silver paste (“GL-6000X16” manufactured by Fukuda Metal Foil Powder Industry Co., Ltd.) by screen printing.

  Furthermore, the precursor of the current collection wiring 17 was formed on the connection part 12g of transparent conductive layer 12D. The precursor of the current collector wiring 17 was formed by applying a silver paste by screen printing and drying.

  In addition, precursors of external connection terminals 18a and 18b for taking out current to the outside were formed on the first current extraction portion 12f and the second current extraction portion 12h of the transparent conductive layer 12A, respectively. The precursor of the terminal for external connection was formed by applying a silver paste by screen printing and drying.

  Furthermore, the precursor of the insulating material 33 made of glass frit was formed so as to enter the first groove 90A and cover the edge of the main body part 12a forming the first groove 90A. The insulating material 33 was formed by applying and drying a paste containing glass frit by screen printing. At this time, the edge of the transparent conductive layer covered with the insulating material 33 was a 0.2 mm portion from the groove 90.

  Further, in order to fix the back sheet 80, in the same manner as the insulating material 33, an annular ring made of glass frit is formed so as to surround the insulating material 33 and pass through the transparent conductive layer 12D, the transparent conductive layer 12E, and the transparent conductive layer 12F. The precursor of the connection part 14 was formed. At this time, the precursor of the connecting portion 14 was formed so that the precursor of the current collecting wiring 17 was disposed inside thereof. Moreover, the connection part 14 was formed so that the 1st electric current extraction part and the 2nd electric current extraction part may be arrange | positioned on the outer side. The connecting part 14 was formed by applying and drying a paste containing glass frit by screen printing.

  Furthermore, the precursor of the oxide semiconductor layer 13 was formed on each main body part 12a of the transparent conductive layers 12A to 12D. The precursor of the oxide semiconductor layer 13 was obtained by sequentially forming the precursor of the light absorption layer and the precursor of the reflective layer. At this time, the precursor of the light absorption layer is 95: 5 (mass ratio) of the first titanium oxide (21NR manufactured by JGC Catalysts & Chemicals) and the second titanium oxide (PST-400C manufactured by JGC Catalysts & Chemicals). A titanium oxide nanoparticle paste for forming a light absorption layer containing the mixed titanium oxide mixture was applied in a square shape by screen printing and dried at 150 ° C. for 10 minutes.

  Moreover, the precursor of a reflection layer contains 2nd titanium oxide (PST-400C by JGC Catalysts & Chemicals Co., Ltd.) on the surface on the opposite side to transparent conductive layers 12A-12D among the surfaces of the precursor of a light absorption layer. The reflective layer-forming titanium oxide nanoparticle paste was applied in a square shape by screen printing and dried at 150 ° C. for 10 minutes.

Next, a precursor of the connection terminal 16, a precursor of the current collector wiring 17, a precursor of the external connection terminals 18a and 18b, a precursor of the insulating material 33, a precursor of the connecting portion 14, a precursor of the insulating material 33, The precursor of the oxide semiconductor layer 13 was baked at 500 ° C. for 15 minutes to form the connection terminal 16, the current collector wiring 17, the external connection terminals 18 a and 18 b, the connecting portion 14, the insulating material 33, and the oxide semiconductor layer 13. . Thus, the working electrode 10 having the connecting portion 14 and the conductive substrate 15 was obtained. At this time, the width of the conductive material connection portion of the connection terminal 16 was 1.0 mm, and the width of the conductive material non-connection portion was 0.3 mm. Further, the length along the extending direction of the conductive material connecting portion was 7.0 mm, and the length along the extending direction of the conductive material non-connecting portion was 7.0 mm. Further, as shown in Table 1, the ratio T (= T2 / T1) of the area T2 of the non-conductive region to the total area T1 of the observation region 98a in the cross section of the connection terminal was 25 area%. The dimensions of the current collector wiring 17, the external connection terminals 18 a and 18 b, the connecting portion 14, and the oxide semiconductor layer 13 were as follows.

Current collecting wiring 17: thickness 4 μm, width 200 μm, length 79 mm along the X direction in FIG. 2, length 21 mm along the direction orthogonal to the X direction in FIG.
External connection terminals 18a and 18b: thickness 20 μm, width 2 mm, length 7 mm
Connection part 14: thickness 50 μm, width 3 mm
Oxide semiconductor layer 13: thickness 14 μm, length 17 mm in the X direction in FIG. 2, length 42.1 mm in the direction perpendicular to the X direction in FIG.

  Thus, a working electrode was obtained.

  Next, the working electrode obtained as described above contains 0.2 mM of a photosensitizing dye composed of Z907, a solvent, and a mixed solvent obtained by mixing acetonitrile and tert-butanol at a volume ratio of 1: 1. After being immersed in the above dye solution for a whole day and night, it was taken out and dried, and a photosensitizing dye was supported on the oxide semiconductor layer.

Then, the top of the oxide semiconductor layer, dimethylpropyl imidazolium iodide, _{I 2,} respectively guanidinium thiocyanate in a solvent consisting of 3-methoxy propionitrile 2M, 0.002 M, the concentration of 0.1M The electrolyte thus obtained was applied by screen printing and dried to place the electrolyte.

  Next, a first integrated sealing portion forming body for forming the first sealing portion was prepared. As the first integrated sealing portion forming body, a single sealing resin film made of maleic anhydride-modified polyethylene (trade name: Binnel 4164, manufactured by DuPont) having a size of 8.0 cm × 4.6 cm × 50 μm is prepared. The resin film for sealing was obtained by forming four rectangular openings. At this time, each opening has a size of 1.7 cm × 4.4 cm × 50 μm, the width of the annular portion is 2 mm, and the width of the partition portion that partitions the inner opening of the annular portion is 2.6 mm. The 1st integrated sealing part formation body was produced.

  Then, after the first integrated sealing portion forming body is overlaid on the insulating material 33 on the working electrode, the first integrated sealing portion forming body is bonded to the insulating material 33 on the working electrode by heating and melting. It was.

  Next, four counter electrodes were prepared. Of the four counter electrodes, two counter electrodes were prepared by forming a catalyst layer of platinum having a thickness of 5 nm on a 4.6 cm × 1.9 cm × 40 μm titanium foil by sputtering. The remaining two counter electrodes among the four counter electrodes were prepared by forming a catalyst layer made of platinum having a thickness of 5 nm on a 4.6 cm × 2.0 cm × 40 μm titanium foil by sputtering. In addition, another first integrated sealing portion forming body was prepared, and this first integrated sealing portion forming body was adhered to the surface of the counter electrode facing the working electrode in the same manner as described above. .

Then, the first integrated sealing portion forming body bonded to the working electrode and the first integrated sealing portion forming body bonded to the counter electrode are opposed to each other, and the first integrated sealing portion forming bodies are overlapped with each other. Combined. In this state, the first integrated sealing portion forming body was heated and melted while pressurizing the first integrated sealing portion forming body. Thus, the first sealing portion was formed between the working electrode and the counter electrode. At this time, the width P of the adhesive portion between the partition portion of the first integrated sealing portion and the surface on the conductive substrate side of the counter electrode, the conductive substrate of the annular portion and the counter electrode of the first integrated sealing portion The width Q of the adhesive portion with the side surface, the width R of the partition portion of the first integrated sealing portion, and the width T of the annular portion were as follows.

P = 1.0mm
Q = 2.0mm
R = 2.6mm
T = 2.2mm

  Next, a second integrated sealing part was prepared. The second integrated sealing portion is prepared by preparing a sealing resin film made of maleic anhydride-modified polyethylene (trade name: Binnel, manufactured by DuPont) of 8.0 cm × 4.6 cm × 50 μm. It was obtained by forming four rectangular openings in the stopping resin film. At this time, each opening has a size of 1.7 cm × 4.4 cm × 50 μm, the width of the annular portion is 2 mm, and the width of the partition portion that partitions the inner opening of the annular portion is 2.6 mm. A second integrated sealing portion was prepared. The second integrated sealing portion was bonded to the counter electrode so as to sandwich the edge of the counter electrode together with the first integrated sealing portion. At this time, the first integrated sealing portion and the second integrated sealing portion were bonded to the counter electrode and the first integrated sealing portion by heating and melting while pressing the second integrated sealing portion against the counter electrode.

  Next, the desiccant sheet was affixed with the double-sided tape on the metal substrate of each counter electrode. The dimensions of the desiccant sheet were 1 mm thick × 3 cm long × 1 cm wide, and a zeo sheet (trade name, manufactured by Shinagawa Kasei Co., Ltd.) was used as the desiccant sheet.

  Next, as shown in FIG. 2, the bypass diodes 70 </ b> A to 70 </ b> C are respectively connected to the three partition portions of the second integrated sealing portion, and the silver paste is connected to the metal substrate 21 of the counter electrode 20 from the terminals at both ends of the bypass diode. Was fixed by coating. At this time, the silver paste was composed of silver particles as metal particles, a polyester resin as a binder resin, and toluene as an organic solvent. At this time, the content rate of silver particles, polyester resin, and toluene in the silver paste was 80% by mass, 10% by mass, and 10% by mass, respectively. Further, the bypass diode 70D is applied on the annular portion of the second integrated sealing portion of the DSC 50D among the four DSCs 50A to 50D, and the silver paste is applied so as to be connected from one of the terminals at both ends of the diode to the counter electrode. Fixed by. Thus, the conductive material 60Q was formed so as to connect the two adjacent bypass diodes to the four bypass diodes 70A to 70D. At this time, the conductive material 60Q was formed by drying and curing the silver paste in a dry environment (dew point of −30 ° C. or lower) for 24 hours. As the bypass diode, RB751V-40 manufactured by ROHM was used.

  Further, the conductive material 60P was formed by applying and curing the silver paste so as to connect the conductive materials 60Q between the bypass diodes and the conductive material connecting portions on the three transparent conductive layers 12A to 12C. Further, for the bypass diode 70A, the conductive material 60P was formed by applying and curing the silver paste so as to be connected to the conductive material connecting portion on the transparent conductive layer 12E. At this time, the conductive material 60P was formed by drying and curing the silver paste in a dry environment (dew point of −30 ° C. or lower) for 24 hours. As shown in Table 1, the ratio S (= S2 / S1) of the area S2 of the non-conductive region to the total area S1 of the observation region 97a in the cross section of the conductive materials 60P and 60Q was 40 area%. In addition, voids were observed in the non-conductive region.

  Next, butyl rubber (“Aikamelt” manufactured by Aika Kogyo Co., Ltd.) was applied onto the connecting portion 14 with a dispenser while heating at 200 ° C. to form a precursor of the bonded portion. On the other hand, a laminate is prepared by laminating a film (thickness 50 μm) made of polybutylene terephthalate (PBT) resin film (thickness 50 μm), aluminum foil (thickness 25 μm), and binel (trade name, manufactured by DuPont) in this order. did. And it piled up on the peripheral part of this laminated body 80A, and the precursor of the adhesion part 80B, and pressurized for 10 seconds. In this way, a back sheet 80 composed of the bonding portion 80B and the laminated body 80A was obtained at the connecting portion 14. A DSC module was obtained as described above.

(Examples 2-7 and Comparative Examples 1-2)
Except that the non-conductive region ratio S in the conductive materials 60P and 60Q was changed as shown in Table 1 by changing the content of silver particles in the silver paste as shown in Table 1, the same as in Example 1. A DSC module was obtained.

[Characteristic evaluation]
The DSC modules of Examples 1 to 7 and Comparative Examples 1 and 2 obtained as described above were evaluated for photoelectric conversion characteristics and durability.

(Photoelectric conversion characteristics)
The DSC module of Examples 1-7 and Comparative Examples 1-2 obtained as described above, the output A ₀ immediately after production was measured by the illuminance under 200 lux, as an index of the photoelectric conversion characteristics. The results are shown in Table 1. At this time, a white LED (product name “E-CORE LEL-SL5N-F”, manufactured by Toshiba Corporation) was used as a light source. Further, a voltage / current generator (product name “R6246”, manufactured by ADVANTEST) was used for measurement of output.

The acceptance criteria for photoelectric conversion characteristics were as follows.

Acceptance criteria: Output A ₀ is 165 μW or more

(durability)
About the DSC modules of Examples 1 to 7 and Comparative Examples 1 and 2 used for the measurement of the photoelectric conversion characteristics, the temperature was increased from −40 ° C. to 90 ° C. and then decreased from 90 ° C. to −40 ° C. The cycle to be carried out was set to 1 cycle, and the thermal cycle test was performed 200 cycles. Then, under illuminance of 200 lux in the same manner as described above to measure the output A _1, it was calculated reduction rate of the output based on the following formula. The results are shown in Table 1.

Output reduction rate (%) = 100 × (A ₀ −A ₁ ) / A ₀

The acceptance criteria for durability were as follows.

Acceptance criteria: Output reduction rate is 15% or less

  As shown in Table 1, all the DSC modules of Examples 1 to 7 reached the acceptance standard in terms of photoelectric conversion characteristics and durability. On the other hand, the DSC modules of Comparative Examples 1 and 2 did not reach the acceptance standard in terms of photoelectric conversion characteristics or durability.

  From the above results, it was confirmed that the dye-sensitized solar cell element of the present invention has excellent photoelectric conversion characteristics and durability.

DESCRIPTION OF SYMBOLS 11 ... Transparent substrate 12 ... Transparent conductive layer 15 ... Conductive substrate (1st electrode)
16: Connection terminal (first electrode)
20 ... Counter electrode (second electrode)
21 ... Metal substrate 33 ... Insulating material (first electrode)
50, 50A to 50D ... Dye-sensitized solar cell 60P, 60Q ... Conductive material 100, 200, 300, 400 ... Dye-sensitized solar cell module (dye-sensitized solar cell element)
500 ... Dye-sensitized solar cell element

Claims (6)

Having at least one dye-sensitized solar cell;
The dye-sensitized solar cell is
A first electrode having a transparent substrate and a transparent conductive layer provided on the transparent substrate;
A second electrode facing the first electrode and including a metal substrate;
A conductive material connected to the metal substrate of the second electrode,
The conductive material includes metal particles and a binder resin,
Dye whose non-conductive region ratio S, which is the ratio of the area S2 of the non-conductive region excluding the metal particles from the observation region in the total area S1 of the observation region in the cross section of the conductive material, is 40 to 80 area% Sensitized solar cell element.   The dye-sensitized solar cell element according to claim 1, wherein the conductive material includes the binder resin and voids between the metal particles.   The dye-sensitized solar cell element according to claim 1 or 2, wherein the metal particles are silver particles. A connection terminal connected to the conductive material of the at least one dye-sensitized solar cell;
The connection terminal is provided on an insulated transparent conductive layer adjacent to the transparent conductive layer of the dye-sensitized solar cell having the conductive material to which the connection terminal is connected;
The said connection terminal contains a metal particle, The said metal particle contained in the said connection terminal is comprised with the same metal as the said metal particle contained in the said electrically-conductive material. Dye-sensitized solar cell element. A connection terminal connected to the conductive material of the at least one dye-sensitized solar cell;
The connection terminal is provided on the insulated transparent conductive layer adjacent to the transparent conductive layer of the dye-sensitized solar cell having the conductive material to which the connection terminal is connected,
The connection terminal includes metal particles;
The non-conductive region in which the non-conductive region ratio S in the conductive material is the ratio of the area T2 of the non-conductive region excluding the metal particles from the observation region in the total area T1 of the observation region in the cross-section of the connection terminal The dye-sensitized solar cell element according to any one of claims 1 to 3, wherein the dye-sensitized solar cell element is larger than the ratio T. Having a plurality of the dye-sensitized solar cells,
The dye-sensitized solar conductive layer adjacent to the transparent conductive layer of the dye-sensitized solar cell having the conductive material to which the connection terminal is connected has the conductive material to which the connection terminal is connected. The dye-sensitized solar cell element according to claim 4 or 5, which is a transparent conductive layer of a dye-sensitized solar cell adjacent to the solar cell or a transparent conductive layer which does not constitute a part of the dye-sensitized solar cell.

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