JP6667255B2 - Battery pack and method of manufacturing battery pack - Google Patents

Description

  The present invention relates to an assembled battery in which a plurality of unit cells are stacked and a method for manufacturing the assembled battery.

  Conventionally, there is an assembled battery in which a plurality of unit cells are stacked (see Patent Document 1). The cell has an electrode tab for inputting and outputting power. The electrode tabs of each cell are electrically connected by a bus bar having conductivity.

  In Patent Literature 1, an electrode tab of a unit cell protrudes in a direction orthogonal to the stacking direction of the unit cell. On the other hand, the bus bar is provided with a concave portion and a convex portion which are formed in a wave shape in a direction orthogonal to the laminating direction so as to sandwich each electrode tab independently along the laminating direction. The electrode tabs of each unit cell are joined to the bus bar in a state of being independently inserted into the plurality of recesses of the bus bar.

JP-T-2012-515418A

  In the configuration of Patent Literature 1, when the thickness of each unit cell to be stacked varies, the position of the electrode tab of each unit cell and the position of the recess of the bus bar are relatively shifted. Further, when the positions of the tip portions of the electrode tabs of the respective cells vary along the direction intersecting the stacking direction, the positions of the tip portions of the electrode tabs of the respective cells and the positions of the concave portions of the bus bars are relatively different. Will be shifted. In such a case, an electrode tab that cannot be sufficiently inserted into the recess of the bus bar occurs. The electrode tab may be insufficiently bonded to the bus bar, and may not be able to secure conductivity.

  An object of the present invention is to provide a battery pack and a method for manufacturing the battery pack, which can sufficiently conduct the electrode tabs and the bus bars of each unit cell.

An assembled battery of the present invention for achieving the above object has a battery group, a bus bar, and a spacer. The battery group is formed by stacking a plurality of unit cells each including a flat battery body including a power generation element and an electrode tab derived from the battery body in a thickness direction thereof, and a tip portion of the electrode tab. Are bent along the stacking direction of the unit cells. The bus bar has a flat plate shape, is joined to the front end of the unit cell in a state facing the front end of the electrode tab, and electrically connects the electrode tabs of at least two of the unit cells. A spacer is provided between the electrode tabs of the stacked unit cells. The electrode tab was provided with a hole opened at the base end along the stacking direction. The spacer is a supporting portion that contacts the electrode tab from the side opposite to the bus bar and supports the distal end portion of the electrode tab, and a rib that guides the electrode tab by passing through the hole of the electrode tab. With. The hole of the electrode tab is formed in an elongated shape along a direction facing the bus bar.

In order to achieve the above object, a method for manufacturing an assembled battery according to the present invention uses a battery group, a bus bar, and a spacer. The battery group is formed by stacking a plurality of unit cells each including a flat battery body including a power generation element and an electrode tab derived from the battery body in a thickness direction thereof, and a tip portion of the electrode tab. Are bent along the stacking direction of the unit cells, and a hole is provided at a base end of the electrode tab. The bus bar has a flat plate shape, is joined to the front end of the unit cell in a state facing the front end of the electrode tab, and electrically connects the electrode tabs of at least two of the unit cells. A spacer is disposed between the electrode tabs of the unit cells to be stacked, and a supporting portion that contacts the electrode tab from a side opposite to the bus bar to support the distal end portion of the electrode tab; And a rib that guides the electrode tab by passing through the hole . In this method of manufacturing a battery pack, the bus bar and the tip end of each of the electrode tabs are relatively moved along a direction intersecting the stacking direction, and are aligned with each other along the stacking direction. After bringing the tip portions of the electrode tabs into contact with the support portions, the bus bar and the tip portions of the electrode tabs of at least two of the unit cells are welded to each other.

  According to the assembled battery and the method of manufacturing the assembled battery configured as described above, the bus bar is arranged so as to face the tip of each electrode tab, and the position of the electrode tab is set via the hole of the electrode tab by the rib of the spacer. Guide while regulating. With this configuration, even if the relative positions of the respective electrode tabs are shifted due to variations in the positions of the individual cells along the direction intersecting the stacking direction, each of the electrode tabs and the bus bar are displaced. Can be sufficiently contacted along the support of each spacer. Therefore, according to the assembled battery and the method of manufacturing the assembled battery, the electrode tab and the bus bar of each unit cell can be sufficiently separated without depending on the variation in the position along the direction intersecting the stacking direction of each unit cell. It can be made conductive.

It is a perspective view which shows the battery pack which concerns on embodiment. FIG. 2 is a perspective view showing a state in which the upper press plate, the lower press plate, and left and right side plates are disassembled from the battery pack shown in FIG. FIG. 3 is a perspective view showing a state in which a protective cover is removed from the laminate shown in FIG. 2 and the laminate is exploded into a battery group and a bus bar unit. FIG. 4 is an exploded perspective view showing the bus bar unit shown in FIG. 3. The state in which the anode-side electrode tab of the first cell sub-assembly (unit cells connected in parallel every three pairs) and the cathode-side electrode tab of the second cell sub-assembly (unit cells connected in parallel every three units) are joined together by a bus bar. FIG. FIG. 6A is a perspective view showing a state where a pair of spacers (a first spacer and a second spacer) are attached to a unit cell, and FIG. 6B is a perspective view showing a pair of spacers (a first spacer and a second unit). FIG. 4 is a perspective view showing a state before attaching a second spacer. FIG. 4 is a perspective view illustrating a pair of spacers (a first spacer and a second spacer). 8A is a perspective view showing a cross section of a main part in a state where a bus bar is joined to the electrode tabs of the stacked unit cells, and FIG. 8B is a side view showing FIG. 8A from the side. is there. FIG. 9 is an enlarged side view of a region 9 shown in FIG. It is a figure showing the manufacturing method of an assembled battery concerning an embodiment, and is a perspective view showing typically the state where the members which constitute an assembled battery are laminated on a mounting base in order. FIG. 11 is a perspective view schematically showing a state in which the constituent members of the battery pack are being pressed from above, following FIG. 10. FIG. 12 is a perspective view schematically showing a state in which the side plate is laser-welded to the upper pressing plate and the lower pressing plate, following FIG. 11. FIG. 13 is a perspective view schematically showing a state where some members of the bus bar unit are attached to the battery group, following FIG. 12. FIG. 14A is a side view schematically showing a cross section of a state before the tip of each electrode tab is moved toward the first spacer by the bus bar. FIG. 14B is a side view schematically showing each electrode tab by the bus bar. It is a side view which shows the state after moving the front-end | tip part of the tab toward the 1st spacer typically by a cross section. FIG. 15 is a perspective view schematically showing a state in which the bus bar of the bus bar unit is laser-welded to the electrode tab of the unit cell, following FIGS. 13 and 14; It is a side view which shows the principal part in the state in which the bus bar is laser-joined to the electrode tab of the laminated unit cell by a cross section. FIG. 17 is a perspective view schematically showing a state in which the anode terminal and the cathode terminal are laser-welded to the anode busbar and the cathode busbar, following FIGS. 15 and 16; FIG. 18 is a perspective view schematically showing a state where the protective cover is attached to the bus bar unit, following FIG. 17.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements will be denoted by the same reference symbols, without redundant description. The size and ratio of each member in the drawings are exaggerated for convenience of explanation and may be different from the actual size and ratio. In the drawing, the azimuth is indicated using arrows represented by X, Y, and Z. The direction of the arrow represented by X crosses the stacking direction of the single cells 110 and indicates a direction along the longitudinal direction of the single cells 110. The direction of the arrow represented by Y indicates the direction that intersects the stacking direction of the cells 110 and extends along the short direction of the cells 110. The direction of the arrow represented by Z indicates the stacking direction of the unit cells 110.

  First, an assembled battery 100 according to an embodiment will be described with reference to FIGS.

  FIG. 1 is a perspective view showing an assembled battery 100 according to the embodiment. FIG. 2 shows a state where the upper pressing plate 151, the lower pressing plate 152, and the left and right side plates 153 are disassembled from the battery pack 100 shown in FIG. 1 to expose the entire stacked body 100S with the protective cover 140 attached. It is a perspective view. FIG. 3 is a perspective view of the stacked body 100S shown in FIG. 2 with the protective cover 140 removed, and the stacked body 100S disassembled into a battery group 100G and a bus bar unit 130. FIG. 4 is an exploded perspective view showing the bus bar unit 130 shown in FIG. FIG. 5 shows the anode-side electrode tab 113A of the first cell subassembly 100M (unit cells 110 connected in parallel every three pairs) and the cathode-side electrode tab 113K of the second cell subassembly 100N (unit cells 110 connected in parallel every three pairs). It is a perspective view which shows the state joined by the bus bar 131 disassembled typically. FIG. 6A is a perspective view showing a state where a pair of spacers 120 (a first spacer 121 and a second spacer 122) are attached to the unit cell 110, and FIG. FIG. 9 is a perspective view showing a state before attaching (first spacer 121 and second spacer 122). FIG. 7 is a perspective view showing a pair of spacers 120 (a first spacer 121 and a second spacer 122). FIG. 8A is a perspective view showing a cross section of a main part in a state where the bus bar 131 is joined to the electrode tab 113 of the stacked unit cells 110, and FIG. 8B is a side view of FIG. 8A. It is a side view. FIG. 9 is an enlarged side view of a region 9 shown in FIG.

  In the state shown in FIG. 1, the left front side is referred to as “the front side” of the entire battery pack 100 and each component, and the right rear side is referred to as the “back side” of the entire battery pack 100 and each component. The right front side and the left rear side are referred to as the left and right “sides” of the entire battery pack 100 and each component.

  As shown in FIGS. 1 and 2, the battery pack 100 has a stacked body 100S including a battery group 100G in which a plurality of flat cells 110 are stacked in the thickness direction. The assembled battery 100 further includes a protective cover 140 attached to the front side of the stacked body 100S, and a housing 150 that accommodates the stacked body 100S in a state where each of the unit cells 110 is pressed along the stacking direction of the unit cells 110. And As shown in FIG. 3, the stacked body 100S includes a battery group 100G and a bus bar unit 130 attached to the front side of the battery group 100G and integrally holding a plurality of bus bars 131. The protection cover 140 covers and protects the bus bar unit 130. As shown in FIG. 4, the bus bar unit 130 includes a plurality of bus bars 131 and a bus bar holder 132 to which the plurality of bus bars 131 are integrally attached in a matrix. Of the plurality of bus bars 131, an anode-side terminal 133 is attached to an end on the anode side, and a cathode-side terminal 134 is attached to an end on the cathode side.

  The battery pack 100 according to the embodiment has a battery group 100G, a bus bar 131, and a spacer (first spacer 121), in brief. The battery group 100G is formed by laminating a plurality of unit cells 110 each having a flat battery body 110H including the power generation element 111 and an electrode tab 113 derived from the battery body 110H in the thickness direction thereof. The tip 113 d of the tab 113 is bent along the stacking direction Z of the unit cells 110. The bus bar 131 is formed in a flat plate shape, is joined to the front end portion 113d in a state facing the front end portion 113d of the electrode tab 113 of the unit cell 110, and electrically connects the electrode tabs 113 of at least two unit cells 110. The first spacer 121 is provided between the electrode tabs 113 of the stacked unit cells 110. The electrode tab 113 was provided with a hole 113e opened along the stacking direction Z at the base end 113c. The first spacer 121 is in contact with the electrode tab 113 from the side opposite to the bus bar 131 to support the distal end 113 d of the electrode tab 113, and guides the electrode tab 113 through the hole 113 e of the electrode tab 113. And a rib 121r. Hereinafter, the assembled battery 100 of the embodiment will be described in detail.

  As shown in FIG. 5, a battery group 100G includes a first cell subassembly 100M including three unit cells 110 electrically connected in parallel and a second cell subassembly 100N including three other unit cells 110 electrically connected in parallel. And are connected in series by a bus bar 131.

  The first cell subassembly 100M and the second cell subassembly 100N have the same configuration except for the direction of refraction of the tip 113d of the electrode tab 113 of the unit cell 110. Specifically, the second cell subassembly 100N is obtained by reversing the top and bottom of the unit cell 110 included in the first cell subassembly 100M. However, the refraction direction of the tip portion 113d of the electrode tab 113 of the second cell subassembly 100N is aligned with the refraction direction of the tip portion 113d of the electrode tab 113 of the first cell subassembly 100M on the lower side in the stacking direction Z so as to be the same. ing. Each unit cell 110 has a pair of spacers 120 (first spacer 121 and second spacer 122) attached thereto.

  The unit cell 110 corresponds to, for example, a flat lithium ion secondary battery. As shown in FIGS. 6 and 8, the cell 110 has a battery body 110H in which the power generation element 111 is sealed by a pair of laminated films 112, and is electrically connected to the power generation element 111 and led out from the battery body 110H. And a thin plate-shaped electrode tab 113.

  The power generating element 111 is configured by laminating a plurality of members each having a positive electrode and a negative electrode sandwiched between separators. The power generating element 111 supplies power while receiving and supplying power from the outside, and discharging to an external electric device.

  The laminate film 112 is configured by covering both sides of the metal foil with an insulating sheet. The pair of laminate films 112 cover the power generating element 111 from both sides along the laminating direction Z, and seal four sides thereof. As shown in FIG. 6, the pair of laminated films 112 have an anode-side electrode tab 113A and a cathode-side electrode tab 113K extending outward from between the one end portions 112a in the short direction Y.

  As shown in FIGS. 6 and 7, the laminate film 112 has a pair of connection pins 121i of the first spacer 121 in a pair of connection holes 112e provided at both ends of one end 112a along the short direction Y, respectively. It is inserted. On the other hand, in the laminate film 112, a pair of connection pins 122i are respectively inserted into a pair of connection holes 112e provided at both ends of the other end portion 112b along the short direction Y. The laminated film 112 is formed by bending both end portions 112c and 112d along the longitudinal direction X upward in the laminating direction Z.

  The electrode tab 113 is composed of an anode-side electrode tab 113A and a cathode-side electrode tab 113K, as shown in FIGS. 6, 8 and 9, and is separated from one end 112a of the pair of laminated films 112, respectively. In the state, it extends toward the outside. The anode-side electrode tab 113A is made of aluminum in accordance with the characteristics of the anode-side components in the power generation element 111. The cathode-side electrode tab 113K is made of copper in accordance with the characteristics of the cathode-side components in the power generation element 111.

  As shown in FIGS. 8 and 9, the electrode tab 113 is formed in an L-shape from the base end 113c to the front end 113d adjacent to the battery main body 110H. Specifically, the electrode tab 113 extends from the base end 113c along one of the longitudinal directions X. On the other hand, the tip portion 113d of the electrode tab 113 is formed to be bent along the lower part in the stacking direction Z. The shape of the tip portion 113d of the electrode tab 113 is not limited to an L-shape. The tip portion 113d of the electrode tab 113 is formed in a planar shape so as to face the bus bar 131. The electrode tab 113 may be formed in a U-shape such that the distal end portion 113d is further extended, and the extended portion is folded back toward the battery main body 110H along the proximal end portion 113c. On the other hand, the base end 113c of the electrode tab 113 may be formed in a wavy shape or a curved shape.

  The tip 113d of each of the electrode tabs 113 is bent downward in the stacking direction Z in a unit cell 110 in which a plurality of cells are stacked, as shown in FIGS. Here, as shown in FIG. 5, the assembled battery 100 includes three cells 110 electrically connected in parallel (first cell subassembly 100M) and another three cells 110 electrically connected in parallel (second cell 110). 100N) are connected in series. Therefore, the top and bottom of the unit cell 110 are exchanged for each of the three unit cells 110 so that the positions of the anode-side electrode tab 113A and the cathode-side electrode tab 113K of the unit cell 110 intersect in the stacking direction Z. I have.

  However, simply replacing the top and bottom of each of the three cells 110 causes the position of the tip 113d of the electrode tab 113 to vary in the vertical direction along the stacking direction Z. The light is refracted by adjusting the positions of the tip portions 113d of the 113.

  As shown in FIGS. 8 and 9, the electrode tab 113 has a hole 113e opened in the stacking direction Z at the base end 113c. The hole 113e is formed in an elongated shape along the longitudinal direction X of the electrode tab 113. The hole 113e extends from the base end 113c to the front end 113d of the electrode tab 113, as shown in FIG. The electrode tab 113 is movable within a range between one end 113f and the other end 113g along the longitudinal direction X of the hole 113e when the rib 121r of the first spacer 121 is inserted into the hole 113e.

  In the first cell subassembly 100M shown in the lower part of FIG. 5, the anode side electrode tab 113A is arranged on the right side in the figure, and the cathode side electrode tab 113K is arranged on the left side in the figure. On the other hand, in the second cell subassembly 100N illustrated in the upper part of FIG. 5, the cathode-side electrode tab 113K is arranged on the right side in the figure, and the anode-side electrode tab 113A is arranged on the left side in the figure.

  As described above, even when the arrangement of the anode-side electrode tab 113A and the arrangement of the cathode-side electrode tab 113K are different, the tip 113d of the electrode tab 113 of the unit cell 110 is bent downward along the stacking direction Z. In addition, as shown in FIG. 3, the distal end portion 113d of each electrode tab 113 is disposed on the same surface side of the multilayer body 100S. A double-sided tape 160 is attached to the unit cells 110 located on the upper surfaces of the first cell sub-assembly 100M and the second cell sub-assembly 100N.

  The pair of spacers 120 (the first spacer 121 and the second spacer 122) are arranged between the stacked unit cells 110 as shown in FIGS. 3, 5, and 8. As shown in FIG. 6, the first spacer 121 is provided along one end 112 a of the laminate film 112 from which the electrode tab 113 of the unit cell 110 protrudes. The second spacer 122 is provided along the other end 112b of the laminate film 112, as shown in FIG. The second spacer 122 has a configuration in which the shape of the first spacer 121 is simplified. Each of the unit cells 110 is laminated with a pair of spacers 120 (first spacer 121 and second spacer 122) and then laminated in the laminating direction Z. The pair of spacers 120 (the first spacer 121 and the second spacer 122) are made of reinforced plastics having an insulating property. Hereinafter, after describing the configuration of the first spacer 121, the configuration of the second spacer 122 will be described in comparison with the configuration of the first spacer 121.

  As shown in FIGS. 6 and 7, the first spacer 121 is formed in a rectangular parallelepiped shape that is long along the short direction Y. The first spacer 121 includes mounting portions 121M and 121N at both ends in the longitudinal direction (short direction Y).

  As shown in FIG. 8B, when the first spacers 121 are stacked while attached to the unit cells 110, the upper surfaces 121a of the mounting portions 121M and 121N of one first spacer 121 and the one second spacer 121M. The lower surfaces 121b of the mounting portions 121M and 121N of the other first spacer 121 disposed above the one spacer 121 abut.

  As shown in FIGS. 7 and 8B, the first spacer 121 is provided on the upper surface 121a of one first spacer 121 in order to perform relative positioning of a plurality of unit cells 110 to be stacked. The positioning pin 121c is fitted into a positioning hole 121d which is opened on the lower surface 121b of the other first spacer 121 and corresponds to the position of the positioning pin 121c.

  As shown in FIG. 7, the first spacer 121 has a locating hole 121 e for inserting a bolt connecting the plurality of assembled batteries 100 connected along the stacking direction Z, and a mounting portion along the stacking direction Z. Openings are provided at 121M and 121N, respectively.

  As shown in FIGS. 6B and 7, the first spacer 121 is formed such that a region between the mounting portions 121M and 121N is cut out from the upper side in the stacking direction Z. The cutout portion includes a first support surface 121g and a second support surface 121h along the longitudinal direction of the first spacer 121 (the short direction Y of the cell 110). The first support surface 121g is formed higher in the stacking direction Z than the second support surface 121h, and is located on the unit cell 110 side.

  As shown in FIG. 6, the first spacer 121 places and supports one end 112a of the laminated film 112 from which the electrode tab 113 is projected, by the first support surface 121g. The first spacer 121 includes a pair of connecting pins 121i protruding upward from both ends of the first support surface 121g.

  As shown in FIGS. 8 and 9, the first spacer 121 abuts on the electrode tab 113 from the side opposite to the bus bar 131, and supports the support portion 121 j that supports the distal end portion 113 d of the electrode tab 113 of the unit cell 110. It is provided on the side surface adjacent to the support surface 121h and along the stacking direction Z. The support portion 121j of the first spacer 121 sandwiches the distal end portion 113d of the electrode tab 113 together with the bus bar 131, so that the distal end portion 113d and the bus bar 131 sufficiently contact each other.

As shown in FIGS. 6 to 9, the first spacer 121 has a pair of ribs 121 r that guide the electrode tab 113 by being inserted into the hole 113 e of the electrode tab 113 on the second support surface 121 h. The rib 121r guides the movement of the electrode tab 113 while regulating the position of the electrode tab 113 via the hole 113e of the electrode tab 113. As shown in FIG. 9, the first spacer 121 has a round shape at a portion corresponding to the boundary between the distal end portion 113d and the proximal end portion 113c of the electrode tab 113 (the boundary between the second support surface 121h and the support portion 121j). A portion 121t is provided.

  As shown in FIGS. 6 and 7, the second spacer 122 has a configuration in which the shape of the first spacer 121 is simplified. The second spacer 122 corresponds to a configuration in which a part of the first spacer 121 is deleted along the short direction Y of the cell 110. Specifically, the second spacer 122 is configured by replacing the second support surface 121h and the first support surface 121g of the first spacer 121 with a support surface 122k. Specifically, like the first spacer 121, the second spacer 122 includes the mounting portions 122M and 122N. The second spacer 122 is provided with a support surface 122k at a portion where a region between the mounting portions 122M and 122N is cut out from the upper side in the stacking direction Z. The support surface 122k places and supports the other end 112b of the laminate film 112. Like the first spacer 121, the second spacer 122 includes a positioning pin 122c, a positioning hole, a locate hole 122e, and a connecting pin 122i.

  The bus bar unit 130 includes a plurality of bus bars 131 integrally as shown in FIGS. The bus bar 131 is made of a conductive metal, and electrically connects the tip portions 113d of the electrode tabs 113 of different cells 110 to each other. The bus bar 131 is formed in a flat plate shape, and stands up along the stacking direction Z.

  The bus bar 131 has an anode-side bus bar 131A that is laser-welded with the anode-side electrode tab 113A of one cell 110, and a cathode-side that is laser-welded with the cathode-side electrode tab 113K of another cell 110 that is adjacent along the stacking direction Z. The bus bar 131K is integrally formed by joining.

  The anode-side bus bar 131A and the cathode-side bus bar 131K have the same shape as shown in FIGS. 4 and 8, and are each formed in an L-shape. The anode-side bus bar 131A and the cathode-side bus bar 131K are overlapped with the top and bottom inverted. Specifically, the bus bar 131 joins a bent portion of one end of the anode-side bus bar 131A along the stacking direction Z and a bent portion of one end of the cathode-side bus bar 131K along the stacking direction Z, It is integrated. As shown in FIG. 4, the anode-side bus bar 131 </ b> A and the cathode-side bus bar 131 </ b> K include side portions 131 c from one end in the short direction Y along the long direction X. The side part 131c is joined to the bus bar holder 132.

  The anode-side bus bar 131A is made of aluminum similarly to the anode-side electrode tab 113A. The cathode-side bus bar 131K is made of copper, similarly to the cathode-side electrode tab 113K. The anode-side bus bar 131A and the cathode-side bus bar 131K made of different metals are joined to each other by ultrasonic joining.

  As illustrated in FIG. 5, when the assembled battery 100 is configured by connecting a plurality of sets of three unit cells 110 connected in parallel over a plurality of sets, as illustrated in FIG. Laser welding is performed on the anode-side electrode tabs 113A of the three unit cells 110 adjacent to each other along the stacking direction Z. Similarly, the bus bar 131 laser-welds the portion of the cathode-side bus bar 131K to the cathode-side electrode tabs 113K of three cells 110 adjacent to each other along the stacking direction Z.

  However, among the bus bars 131 arranged in a matrix, the bus bar 131 located at the upper right in FIGS. 3 and 4 corresponds to the terminal end on the anode side of the 21 cells 110 (3 parallel, 7 series). It is composed of only the side bus bar 131A. The anode-side bus bar 131A is laser-bonded to the anode-side electrode tabs 113A of the three uppermost unit cells 110 of the battery group 100G. Similarly, of the bus bars 131 arranged in a matrix, the bus bar 131 located at the lower left in FIGS. 3 and 4 corresponds to the cathode-side end of the 21 cells 110 (3 parallel, 7 series), It is composed of only the cathode side bus bar 131K. The cathode-side bus bar 131K is laser-bonded to the cathode-side electrode tabs 113K of the three lowermost cells 110 of the battery group 100G.

  As shown in FIG. 3, the bus bar holder 132 integrally holds a plurality of bus bars 131 in a matrix so as to face the electrode tabs 113 of each of the unit cells 110 that are stacked. The bus bar holder 132 is made of a resin having an insulating property and is formed in a frame shape.

  As shown in FIG. 4, the bus bar holder 132 is a pair of erects along the stacking direction Z so as to be located on both sides in the longitudinal direction of the first spacer 121 that supports the electrode tab 113 of the unit cell 110. Each has a support 132a. The pair of support portions 132a are fitted on the side surfaces of the mounting portions 121M and 121N of the first spacer 121. The pair of support portions 132a are L-shaped when viewed along the stacking direction Z, and are formed in a plate shape extending along the stacking direction Z. The bus bar holder 132 is provided with a pair of auxiliary support portions 132b that stand up in the stacking direction Z so as to be located near the center of the first spacer 121 in the longitudinal direction. The pair of auxiliary support portions 132b is formed in a plate shape extending along the stacking direction Z.

  As shown in FIG. 4, the bus bar holder 132 includes insulating portions 132 c protruding between the bus bars 131 adjacent to each other along the stacking direction Z. The insulating portion 132c is formed in a plate shape extending along the short direction Y. Each insulating part 132c is provided horizontally between the support part 132a and the auxiliary support part 132b. The insulating part 132c prevents discharge by insulating the bus bars 131 of the unit cells 110 adjacent to each other along the stacking direction Z.

  The bus bar holder 132 may be formed by joining a support 132a, an auxiliary support 132b, and an insulating part 132c, which are independently formed, to each other, or integrally form the support 132a, the auxiliary support 132b, and the insulating 132c. It may be formed by molding.

  As shown in FIGS. 3 and 4, the anode terminal 133 corresponds to a terminal end on the anode side of the battery group 100G configured by alternately stacking the first cell sub-assemblies 100M and the second cell sub-assemblies 100N.

  As shown in FIGS. 3 and 4, the anode-side terminal 133 is joined to the anode-side bus bar 131A located at the upper right in the drawing among the bus bars 131 arranged in a matrix. The anode-side terminal 133 is made of a conductive metal plate. When viewed in the short direction Y, the one end 133b and the other end 133c are arranged along the stacking direction Z with respect to the central portion 133a. It consists of shapes refracted in different directions. One end 133b is laser-joined to anode-side bus bar 131A. The other end 133c connects an external input / output terminal to a hole 133d (including a screw groove) opened in the center.

  As shown in FIGS. 3 and 4, the cathode-side terminal 134 corresponds to the cathode-side terminal of the battery group 100G formed by alternately stacking the first cell sub-assemblies 100M and the second cell sub-assemblies 100N. As shown in FIGS. 3 and 4, the cathode-side terminal 134 is joined to the cathode-side bus bar 131K located at the lower left of the bus bars 131 arranged in a matrix. The cathode terminal 134 has the same configuration as the anode terminal 133.

  As shown in FIGS. 1 to 3, the protective cover 140 covers the bus bar unit 130, so that the bus bars 131 are short-circuited, or the bus bar 131 contacts an external member to cause a short-circuit or a short circuit. To prevent Furthermore, the protection cover 140 causes the anode-side terminal 133 and the cathode-side terminal 134 to face the outside, and causes the power generation elements 111 of each unit cell 110 to charge and discharge. The protective cover 140 is made of plastics having an insulating property.

  As shown in FIG. 3, the protective cover 140 is formed in a flat plate shape and stands up along the stacking direction Z. The protective cover 140 has a shape in which the upper end 140b and the lower end 140c of the side surface 140a are bent along the longitudinal direction X, and is fitted to the bus bar unit 130.

  As shown in FIGS. 2 and 3, the side surface 140 a of the protective cover 140 has a rectangular hole slightly larger than the anode terminal 133 at a position corresponding to the anode terminal 133 provided in the bus bar unit 130. A first opening 140d is provided. Similarly, the side surface 140 a of the protective cover 140 has a second opening 140 e formed of a rectangular hole slightly larger than the cathode terminal 134 at a position corresponding to the cathode terminal 134 provided in the bus bar unit 130. I have.

  As shown in FIGS. 1 and 2, the housing 150 accommodates the battery group 100G in a state where the battery group 100G is pressed in the stacking direction. The upper pressure plate 151 and the lower pressure plate 152 press the power generation element 111 of each unit cell 110 provided in the battery group 100G while sandwiching the power generation element 111, thereby giving an appropriate surface pressure to the power generation element 111.

  The upper pressure plate 151 is disposed above the battery group 100G in the stacking direction Z, as shown in FIGS. The upper pressing plate 151 has a pressing surface 151a protruding downward along the stacking direction Z at the center. The power generating element 111 of each unit cell 110 is pressed downward by the pressing surface 151a. The upper pressure plate 151 includes holding portions 151b extending along the longitudinal direction X from both sides along the short direction Y. The holder 151b covers the receivers 121M and 121N of the first spacer 121 or the receivers 122M and 122N of the second spacer 122. At the center of the holding portion 151b, a locate hole 151c communicating with the positioning hole 121d of the first spacer 121 or the positioning hole 122d of the second spacer 122 along the stacking direction Z is opened. The locating hole 151c allows a bolt for connecting the assembled batteries 100 to pass therethrough. The upper pressing plate 151 is made of a metal plate having a sufficient thickness.

  The lower pressing plate 152 has the same configuration as the upper pressing plate 151 as shown in FIGS. 1 and 2, and the upper pressing plate 151 is turned upside down. The lower pressure plate 152 is disposed below the battery group 100G along the stacking direction Z. The lower pressing plate 152 presses the power generating elements 111 of each of the unit cells 110 upward by the pressing surface 151a protruding upward along the stacking direction Z.

  As shown in FIGS. 1 and 2, the pair of side plates 153 are arranged such that the upper pressing plate 151 and the lower pressing plate 152 that press and hold the battery group 100G from above and below in the stacking direction Z do not separate from each other. The relative positions of the pressing plate 151 and the lower pressing plate 152 are fixed. The side plate 153 is formed of a rectangular metal plate, and stands up in the stacking direction Z. The pair of side plates 153 are joined to the upper pressure plate 151 and the lower pressure plate 152 by laser welding from both sides in the short direction Y of the battery group 100G. Each side plate 153 is subjected to seam welding or spot welding along the longitudinal direction X with respect to a portion of the upper end 153a in contact with the upper pressing plate 151. Similarly, each side plate 153 is subjected to seam welding or spot welding along the longitudinal direction X with respect to a portion of the lower end 153b in contact with the lower pressure plate 152. The pair of side plates 153 cover and protect both sides of the battery group 100G in the lateral direction Y.

  Next, a method of manufacturing the battery pack 100 will be described with reference to FIGS.

  The manufacturing method (manufacturing process) of the assembled battery 100 includes a laminating process of stacking members constituting the assembled battery 100 (FIG. 10), a pressing process of applying pressure to the battery group 100G of the assembled battery 100 (FIG. 11), and A first joining step (FIG. 12) of joining the upper pressing plate 151 and the lower pressing plate 152, and a second joining step of joining the bus bar 131 to the electrode tab 113 of the cell 110 and joining the terminal to the bus bar 131 (FIG. 13 to 17) and a mounting step (FIG. 18) of attaching the protective cover 140 to the bus bar 131.

  The laminating step of laminating the members constituting the assembled battery 100 will be described with reference to FIG.

  FIG. 10 is a diagram illustrating the method of manufacturing the assembled battery 100 according to the embodiment, and is a perspective view schematically illustrating a state in which members configuring the assembled battery 100 are sequentially stacked on the mounting table 701. .

  The mounting table 701 used in the laminating step is formed in a plate shape and provided along a horizontal plane. The mounting table 701 is a positioning pin for positioning the lower pressing plate 152, the first cell sub-assembly 100M, the second cell sub-assembly 100N, and the upper pressing plate 151, which are stacked in this order, along the longitudinal direction X and the short direction Y. 702. The four locate pins 702 stand on the upper surface 701a of the mounting table 701 at predetermined intervals. The distance between the four locate pins 702 corresponds to, for example, the distance between the locate holes 152c provided at the four corners of the upper pressing plate 151. The members constituting the battery pack 100 are stacked using a robot arm, a hand lifter, a collet of a vacuum suction type, or the like.

  In the stacking step, as shown in FIG. 10, the robot arm lowers the lower pressing plate 152 along the stacking direction Z while lowering the lower pressing plate 152 in a state where the locate holes 152 c provided at the four corners thereof are inserted into the locate pins 702. It is mounted on the upper surface 701a of the mounting table 701. Next, the robot arm lowers the first cell subassembly 100M along the stacking direction Z in a state where the locating holes provided in the first spacer 121 and the second spacer 122 of the constituent members are inserted into the locating pins 702. , On the lower pressing plate 152. Similarly, three sets of the second cell sub-assembly 100N and the first cell sub-assembly 100M are alternately stacked by the robot arm. A double-sided tape 160 is attached to the upper surfaces of the first cell sub-assembly 100M and the second cell sub-assembly 100N so as to adhere to a laminated member to be stacked upward. Thereafter, the upper pressing plate 151 is stacked on the first cell sub-assembly 100M by the robot arm while being lowered along the stacking direction Z in a state where the locate holes 151c provided at the four corners thereof are inserted into the locate pins 702.

  The pressurizing step of pressurizing the battery group 100G of the assembled battery 100 will be described with reference to FIG.

  FIG. 11 is a perspective view schematically showing a state where the constituent members of the battery pack 100 are pressed from above, following FIG.

  The pressing jig 703 used in the pressing step includes a pressing portion 703a formed in a plate shape and provided along a horizontal plane, and a supporting portion 703b formed in a cylindrical shape and erected on the upper surface of the pressing portion 703a and joined thereto. Have. The support portion 703b connects an electric stage and a hydraulic cylinder that are driven in the stacking direction Z. The pressing unit 703a moves downward and upward along the stacking direction Z via the support unit 703b. The pressurizing unit 703a presses the contacted laminated member.

  In the pressing step, as shown in FIG. 11, the pressing section 703a of the pressing jig 703 is driven by the electric stage connected to the support section 703b, so that the pressing section 703a is in contact with the upper pressing plate 151 in the stacking direction Z. Descend along the bottom. The battery group 100G is pressed by the upper pressing plate 151 pressed downward and the lower pressing plate 152 mounted on the mounting table 701 while holding the same. An appropriate surface pressure is applied to the power generation element 111 of each of the cells 110 provided in the battery group 100G. The pressing step is continued until the next first joining step is completed.

  A first joining step of joining the side plate 153 to the upper pressing plate 151 and the lower pressing plate 152 will be described with reference to FIG.

  FIG. 12 is a perspective view schematically showing a state in which the side plate 153 is laser-welded to the upper pressing plate 151 and the lower pressing plate 152, following FIG.

  The pressing plate 704 used in the first joining step presses the side plate 153 against the upper pressing plate 151 and the lower pressing plate 152, respectively, and makes the side plate 153 adhere to the upper pressing plate 151 and the lower pressing plate 152, respectively. The push plate 704 is made of metal and formed in a long plate shape. The push plate 704 has a linear slit 704b opened in the main body 704a along the longitudinal direction. The push plate 704 stands upright in its latitudinal direction along the stacking direction Z. The pressing plate 704 allows the laser beam L1 for welding to pass through the slit 704b while pressing the side plate 153 with the main body 704a.

  The laser oscillator 705 is a light source that joins the side plate 153 to the upper pressing plate 151 and the lower pressing plate 152. The laser oscillator 705 is composed of, for example, a YAG (yttrium aluminum garnet) laser. The laser beam L1 derived from the laser oscillator 705 irradiates the upper end 153a and the lower end 153b of the side plate 153 in a state where the optical path is adjusted by, for example, an optical fiber or a mirror and condensed by a condenser lens. The laser beam L1 derived from the laser oscillator 705 may be split by, for example, a half mirror and irradiated simultaneously on the upper end 153a and the lower end 153b of the side plate 153.

  In the first joining step, as shown in FIG. 12, the laser oscillator 705 horizontally scans the upper end 153a of the side plate 153 pressed by the push plate 704 with the laser light L1 via the slit 704b of the push plate 704. Then, the side plate 153 and the upper pressing plate 151 are joined by seam welding at a plurality of locations. Similarly, the laser oscillator 705 horizontally scans the lower end 153b of the side plate 153 pressed by the pressing plate 704 with the laser beam L1 through the slit 704b of the pressing plate 704, and moves the side plate 153 and the lower pressing plate 152. Seam welding is performed over multiple locations.

  A second joining step of joining the bus bar 131 to the electrode tab 113 of the unit cell 110 and joining the terminal to the bus bar 131 will be described with reference to FIGS.

  FIG. 13 is a perspective view schematically showing a state in which some members of the bus bar unit 130 are attached to the battery group 100G, following FIG. FIG. 14A is a side view schematically showing a cross section of a state before the tip portion 113d of each electrode tab 113 is moved toward the first spacer 121 by the bus bar 131, and FIG. FIG. 13 is a side view schematically showing a state after a tip portion 113 d of each electrode tab 113 is moved toward a first spacer 121 by a cross section 131. FIG. 15 is a perspective view schematically showing a state in which the bus bar 131 of the bus bar unit 130 is laser-welded to the electrode tab 113 of the unit cell 110, following FIG. 13 and FIG. FIG. 16 is a side view showing a cross section of a main part in a state where the bus bar 131 is laser-bonded to the electrode tab 113 of the stacked unit cells 110. FIG. 17 is a perspective view schematically showing a state where the anode terminal 133 and the cathode terminal 134 are laser-welded to the anode bus bar 131A and the cathode bus bar 131K, following FIGS. 15 and 16.

  In the second bonding step, as shown in FIGS. 12 and 13, the mounting table 701 is rotated 90 ° counterclockwise in the figure to make the electrode tab 113 of the battery group 100G face the laser oscillator 705. Further, the bus bar holder 132 on which each bus bar 131 is integrally held is continuously pressed by the robot arm while being brought into contact with the corresponding electrode tab 113 of the battery group 100G.

  Here, as schematically shown in FIG. 14A, the positions of the tip portions 113d of the respective electrode tabs 113 are relatively shifted along a direction intersecting the stacking direction Z (longitudinal direction X). . Of the three electrode tabs 113 shown, the center electrode tab 113 has its leading end 113d in contact with the corresponding supporting portion 121j of the first spacer 121. On the other hand, each of the upper and lower electrode tabs 113 of the three electrode tabs 113 shown in the drawing has its tip portion 113d separated from the corresponding supporting portion 121j of the first spacer 121. In the upper electrode tab 113 and the lower electrode tab 113, the distance between the tip 113d and the support portion 121j of the first spacer 121 is different.

  As shown in FIG. 14B, the bus bar 131 is moved along the longitudinal direction X, and the tip 113d of each electrode tab 113 is pressed against the corresponding support 121j of each first spacer 121. When each of the upper and lower electrode tabs 113 among the three electrode tabs 113 moves toward the first spacer 121, its respective base end 113c is slightly curved. In this state, the bus bar 131 is irradiated with the laser beam L1 for welding, and the bus bar 131 and the distal end portion 113d of each electrode tab 113 are welded. Here, after each cell 110 is slightly moved to the bus bar 131 side in advance, each electrode tab 113 is pressed by the bus bar 131 while sufficiently urging it toward the first spacer 121 side. Can also.

  As shown in FIGS. 15 and 16, the laser oscillator 705 irradiates the bus bar 131 with the laser beam L <b> 1, and joins the bus bar 131 and the tip 113 d of the electrode tab 113 by seam welding or spot welding. Thereafter, as shown in FIG. 17, the anode-side terminal 133 is joined to the anode-side bus bar 131A (upper right in FIG. 4) corresponding to the anode-side end of the bus bars 131 arranged in a matrix. Similarly, the cathode-side terminal 134 is joined to the cathode-side bus bar 131K (lower left in FIG. 4) corresponding to the cathode-side end of the bus bars 131 arranged in a matrix.

  A mounting process for attaching the protective cover 140 to the bus bar 131 will be described with reference to FIG.

  FIG. 18 is a perspective view schematically showing a state in which the protective cover 140 is attached to the bus bar unit 130, following FIG.

  In the mounting process, the protection cover 140 is attached to the bus bar unit 130 while the upper end 140b and the lower end 140c of the protection cover 140 are fitted to the bus bar unit 130 using a robot arm. The upper end 140b and the lower end 140c of the protective cover 140 may be bonded to the bus bar unit 130 with an adhesive. The protective cover 140 exposes the anode terminal 133 from the first opening 140d to the outside, and exposes the cathode terminal 134 from the second opening 140e to the outside. The bus bar unit 130 is covered with the protective cover 140 to prevent short-circuiting between the bus bars 131 and short-circuiting and leakage of the bus bar 131 by contacting the bus bar 131 with an external member. The assembled battery 100 that has been manufactured is removed from the mounting table 701 and carried out to an inspection process for inspecting battery performance and the like.

  The manufacturing method of the battery pack 100 described with reference to FIGS. 10 to 18 is an automatic machine in which the entire process is controlled by a controller, a semi-automatic machine in which a part of the process is performed by an operator, or a manual in which the operator performs the entire process. It may be embodied by any form of the machine.

  According to the battery pack 100 and the method of manufacturing the battery pack 100 according to the above-described embodiment, the following operational effects can be obtained.

  The battery pack 100 of the embodiment has a battery group 100G, a bus bar 131, and a spacer (first spacer 121). The battery group 100G is formed by laminating a plurality of unit cells 110 each having a flat battery body 110H including the power generation element 111 and an electrode tab 113 derived from the battery body 110H in the thickness direction thereof. The tip 113 d of the tab 113 is bent along the stacking direction Z of the unit cells 110. The bus bar 131 is formed in a flat plate shape, is joined to the front end portion 113d in a state facing the front end portion 113d of the electrode tab 113 of the unit cell 110, and electrically connects the electrode tabs 113 of at least two unit cells 110. The first spacer 121 is provided between the electrode tabs 113 of the stacked unit cells 110. The electrode tab 113 was provided with a hole 113e opened along the stacking direction Z at the base end 113c. The first spacer 121 is in contact with the electrode tab 113 from the side opposite to the bus bar 131 to support the distal end 113 d of the electrode tab 113, and guides the electrode tab 113 through the hole 113 e of the electrode tab 113. And a rib 121r.

  The method of manufacturing the assembled battery 100 uses the battery group 100G, the bus bar 131, and the spacer (the first spacer 121). The battery group 100G is formed by laminating a plurality of unit cells 110 each having a flat battery body 110H including the power generation element 111 and an electrode tab 113 derived from the battery body 110H in the thickness direction thereof. The distal end 113d of the tab 113 is bent in the stacking direction Z of the unit cells 110, and the base 113c of the electrode tab 113 is provided with a hole 113e. The bus bar 131 is formed in a flat plate shape, is joined to the front end portion 113d in a state facing the front end portion 113d of the electrode tab 113 of the unit cell 110, and electrically connects the electrode tabs 113 of at least two unit cells 110. The first spacer 121 is disposed between the electrode tabs 113 of the unit cells 110 to be stacked. The first spacer 121 abuts on the electrode tab 113 from the side opposite to the bus bar 131 to support the distal end 113 d of the electrode tab 113. And a rib 121r that guides the electrode tab 113 through the hole 113e. In the method of manufacturing the battery pack 100, the bus bar 131 and the distal end 113 d of each of the electrode tabs 113 are relatively moved along a direction intersecting with the stacking direction Z, while moving each other along the stacking direction Z. After the tip portions 113d of the electrode tabs 113 are brought into contact with the support portions 121j whose positions are aligned, the bus bar 131 and the tip portions 113d of the electrode tabs 113 of at least two unit cells 110 are connected to each other. Weld.

  According to the assembled battery 100 and the method of manufacturing the assembled battery 100 having such a configuration, the bus bar 131 is disposed so as to face the tip portion 113d of each of the electrode tabs 113, and the ribs 121r of the first spacer 121 form the electrode tabs 113. It guides while regulating the position of the electrode tab 113 through the hole 113e. In this way, even if the relative positions of the respective electrode tabs 113 are shifted due to variations in the positions of the unit cells 110 along the direction intersecting the stacking direction, the respective electrode tabs are shifted. 113 and the bus bar 131 can be brought into sufficient contact along the support portions 121j of the respective first spacers 121. Therefore, according to the assembled battery 100 and the method of manufacturing the assembled battery 100, the electrode tab 113 of each of the cells 110 does not depend on the variation in the position of each of the cells 110 along the direction intersecting the stacking direction Z. And the bus bar 131 can be made sufficiently conductive.

  In particular, according to the manufacturing method of the assembled battery 100 having such a configuration, in a state where the rib 121r of the first spacer 121 is inserted into the hole 113e of the electrode tab 113, the position of the electrode tab 113 is regulated and guided. The positions of the electrode tab 113 and the bus bar 131 of each cell 110 can be aligned in a plane. According to such a method of manufacturing the battery pack 100, a gap between non-welded objects, which is important in a welding method using a non-contact heat input method represented by laser welding, can be stabilized.

  Further, the hole 113e of the electrode tab 113 is formed in an elongated shape along the direction (longitudinal direction X) facing the bus bar 131.

  According to such a configuration, when the electrode tab 113 moves toward the support portion 121j of the first spacer 121, the hole 113e of the electrode tab 113 interferes with the rib 121r of the first spacer 121, and the electrode tab 113 is moved. Damage can be prevented.

  According to such a configuration, when the battery pack 100 is operated (charging or discharging), the electrode tab 113 is drawn into the battery body 110H due to the expansion of the battery body 110H. The hole 113e of the electrode tab 113 does not easily contact the rib 121r of the first spacer 121. Therefore, damage to the electrode tab 113 caused by the expansion of the battery main body 110H can be suppressed.

  Further, the hole 113e of the electrode tab 113 extends to the tip 113d.

  According to such a configuration, variation in the position of each electrode tab 113 in a direction intersecting the stacking direction of each unit cell 110 is widely absorbed, and the position of the electrode tab 113 is changed by the rib 121r of the first spacer 121. Can guide while regulating.

Furthermore, the first spacer 121 is made provided with a rounded shaped portion 121t which a portion facing the boundary between the distal end portion 113d and the base end portion 113c of the electrode tab 113 formed by radiusing.

According to such a configuration, a dimensional change of the electrode tab 113 along the stacking direction Z is absorbed by the gap generated in the rounded portion 121t of the first spacer 121, and the tip portion 113d of the electrode tab 113 is moved to the first position. The spacer 121 can be sufficiently brought into contact with the support portion 121j. Further, according to such a configuration, the tip 113 d of the electrode tab 113 can be fixed to the first spacer 121 without depending on the shape error of the bent portion of the electrode tab 113 and the shape error of the end of the first spacer 121. Can be sufficiently brought into contact with the supporting portion 121j.

  In the method of manufacturing the assembled battery 100, the electrode tab 113 and the first spacer 121 are brought into contact with each other by using the bus bar 131 formed in an elongated shape along the direction in which the hole 113e faces the bus bar 131 (longitudinal direction X). The electrode tab 113 is brought into contact with the inner peripheral surface of the hole 113e of the electrode tab 113 and the outer peripheral surface of the rib 121r of the first spacer 121 along a direction (longitudinal direction X) intersecting the stacking direction Z. To move.

  According to such a configuration, the electrode tab 113 can be accurately moved on a plane formed by the longitudinal direction X and the lateral direction Y while being along the rib 121r of the first spacer 121. Therefore, each of the electrode tabs 113 and the bus bar 131 can be brought into contact with the support portion 121j of each of the first spacers 121 with high accuracy.

  In addition, the present invention can be variously modified based on the configurations described in the claims, and those modifications are also included in the scope of the present invention.

100 assembled batteries,
100S laminate,
100G battery group,
100M first cell subassembly,
100N second cell subassembly,
110 cells,
110H battery body,
111 power generation elements,
112 laminated film,
113, 113 electrode tab,
113A anode side electrode tab,
113K cathode side electrode tab,
113c proximal end,
113d tip,
113e hole,
120 a pair of spacers,
121 first spacer,
121j support,
121r rib,
121t R-shaped part ,
122 second spacer,
130 busbar unit,
131 Busba,
131A anode side bus bar (first bus bar),
131K cathode side bus bar (second bus bar),
132 busbar holder,
133 anode side terminal,
134 cathode side terminal,
140 protective cover,
150 housing,
151 upper pressure plate,
152 lower pressure plate,
153 side plate,
153a upper end,
153b lower end,
160 double-sided tape,
701 mounting table,
702 Locate pin,
703 pressure jig,
704 pressing plate,
705 laser oscillator,
L1 laser light,
X a longitudinal direction (intersecting with the stacking direction of the cells 110 and of the cells 110);
Y a short direction (intersecting the stacking direction of the cells 110 and of the cells 110),
Z Lamination direction (of cell 110).

Claims (5)

A plurality of unit cells each including a flat battery body including a power generation element and an electrode tab derived from the battery body are stacked in a thickness direction thereof, and the tip of the electrode tab is formed of the unit cell. A battery group refracted along the stacking direction of
A flat plate-shaped bus bar that is joined to the front end portion in a state facing the front end portion of the electrode tab of the unit cell, and electrically connects the electrode tabs of at least two of the unit cells;
The battery group includes a spacer disposed between the electrode tabs of the stacked unit cells,
The electrode tab includes a hole that is open at the base end along the stacking direction,
The spacer is a supporting portion that contacts the electrode tab from the side opposite to the bus bar and supports the distal end portion of the electrode tab, and a rib that guides the electrode tab by passing through the hole of the electrode tab. equipped with a,
An assembled battery , wherein the hole of the electrode tab is formed in an elongated shape along a direction facing the bus bar . The battery pack according to claim 1, wherein the hole of the electrode tab extends to the tip. The spacer is assembled battery according to claim 1 or 2 comprising including the tip and the rounded shaped portion which the portion facing the boundary between the proximal portion formed by radiusing of the electrode tabs. A plurality of unit cells each including a flat battery body including a power generation element and an electrode tab derived from the battery body are stacked in a thickness direction thereof, and the tip of the electrode tab is formed of the unit cell. A battery group refracted along the stacking direction of
A flat plate-shaped bus bar that is joined to the front end portion in a state facing the front end portion of the electrode tab of the unit cell and electrically connects the electrode tabs of at least two of the unit cells;
A support portion that is disposed between the electrode tabs of the unit cells to be stacked and that abuts on the electrode tab from the side opposite to the bus bar to support the tip portion of the electrode tab, and a hole in the electrode tab. Using a spacer having a rib inserted therethrough to guide the electrode tab,
The bus bar and the tip end of each of the electrode tabs are relatively moved along a direction intersecting with the laminating direction, and with respect to each of the supporting portions whose positions are aligned along the laminating direction. A method of manufacturing an assembled battery, wherein the bus bar and the tip portions of the electrode tabs of at least two unit cells are welded to each other after the tip portions of the electrode tabs are brought into contact with each other. Using the bus bar formed in a long shape along the direction in which the hole faces the bus bar,
The electrode tab and the spacer are brought into contact with each other, and the inner peripheral surface of the hole of the electrode tab and the outer peripheral surface of the rib of the spacer are brought into contact with each other along a direction intersecting the stacking direction. The method according to claim 4 , wherein the electrode tab is moved.