JP6344510B2 - Secondary battery - Google Patents

Description

  The present invention relates to a secondary battery. More specifically, the present invention relates to a secondary battery having an electrode body in which positive and negative electrode plates are laminated with a separator interposed therebetween.

  A secondary battery is one in which an electrode body is accommodated together with an electrolytic solution in a battery case. The electrode body is configured, for example, by laminating a strip-shaped positive electrode plate and negative electrode plate formed by forming an active material layer containing an active material on the surface of a current collector foil, with a separator interposed therebetween. As a prior art regarding a secondary battery having such an electrode body, for example, Patent Document 1 can be cited.

  Patent Document 1 describes a secondary battery having a laminated electrode assembly (electrode body) formed by laminating positive and negative electrode plates together with a separator in a stacked manner. Moreover, in patent document 1, the electrode plate has the part which the current collection foil in which the active material layer is not formed protruded from the part in which the active material layer is formed is exposed. And in an electrode body, the electrode tab is formed by being bundled in the state which the exposed part of the current collection foil protruded.

  In Patent Document 1, the electrode tab is connected to a terminal provided on a lid member that closes an opening of a case for inserting an electrode body. Moreover, the secondary battery of patent document 1 has the film currently fixed to the cover member or the terminal while covering an electrode body. And when inserting an electrode body into a case, it is supposed that it can carry out, receiving the load of an electrode body with the film which covers an electrode body. Thereby, it is said that the load of the electrode body is prevented from being applied to the electrode tab, and the tearing of the electrode tab can be suppressed.

JP 2014-38736 A

  By the way, when the electrode body is inserted into the case through the opening, a pressing load is applied to the electrode body to press it toward the case. In the conventional technique as described above, the insertion load when inserting the electrode body into the case is usually applied to the side surface of the electrode body on the side where the electrode tab protrudes. However, since the side surface of the electrode body is constituted by the end portions of the electrode plate and the separator, the strength is not so high. That is, the end portions of the electrode plate and the separator on the side surface of the electrode body subjected to the insertion load may be deformed due to breakage or breakage. And there existed a possibility that the quality of a secondary battery might fall by the deformation | transformation of the electrode plate and separator in an electrode body.

  The present invention has been made for the purpose of solving the problems of the prior art described above. That is, the problem is to provide a secondary battery in which damage to the electrode plate and separator in the electrode body is prevented.

  The secondary battery of the present invention, which has been made for the purpose of solving this problem, has a positive and negative electrode plate formed by forming an active material layer on a current collector foil, and an electrode body formed by laminating a separator between them. , Having a case body having an opening and a sealing member for closing the opening of the case body, a battery case for housing the electrode body therein, and being assembled to the sealing member and being attached to the electrode body inside the battery case An electrode terminal having a connection end to be connected and an exposed end exposed to the outside of the battery case. The electrode plate is formed with an active material layer, and the other positive and negative electrode plates and separators are laminated by lamination in the electrode body. A charging / discharging portion that overlaps with each other, and an active material layer is not formed and the current collector foil is exposed, and a protruding portion that is a portion protruding from a part of the end portion of the charging / discharging portion. The electrode body is bundled by stacking in such a manner that only the positive and negative of the positive and negative electrode plates protrude from the stacked portion, and the stacked portion where both the charge and discharge portions of the positive and negative electrode plates are stacked together with the separator. And having an electrode tab connected to the connection end of the electrode terminal, and being accommodated in the battery case with the side surface of the laminated portion from which the electrode tab protrudes facing the sealing member The first and second secondary batteries are provided so as to face each other, and on each side facing the other, inclined surfaces are formed so as to be inclined away from the other toward the tip side. An insulating member having an insulative portion at one end while providing a gap between the first and second inclined portions, and the electrode tab is laminated with a connection location connected to the connection end of the electrode terminal Outside of the stacking direction of the protrusions Both sides have electrode tab inclined portions that are inclined in a direction narrower in the stacking direction as a portion farther from the stacked portion, and the insulating member has both the tip side of the first and second inclined portions facing the stacked portion. In this state, the inclined surfaces of the first and second inclined portions sandwich the outer surfaces of the electrode tab inclined portions in the stacking direction, and the electrode tabs are passed through the gaps between the first and second inclined portions. , Projecting toward the other end opposite to the first and second inclined portions, and further sandwiched between both sides of the electrode tab inclined portion in the stacking direction and the sealing member. There is a secondary battery characterized by that.

  In the secondary battery of the present invention, a pressing load applied to the outer surface of the sealing member when the electrode body is inserted into the case body is applied to the electrode tab inclined portion via the insulating member. The ends of the electrode tab inclined portion to which the pressing load is applied are not exposed on the outer surfaces in the stacking direction. In addition, in the electrode tab inclined portion, the pressing load due to the inclined surfaces of the first and second inclined portions is equal to the thickness direction of the plurality of protruding portions constituting the electrode tab inclined portion by the amount of inclination. Can receive. And since the electrode tab inclination part is comprised by the lamination | stacking of several protrusion part, it is a high intensity | strength with respect to the press of the thickness direction of the protrusion part. Therefore, in the secondary battery of the present invention, damage to the electrode plate and the separator in the electrode body is prevented.

  In the secondary battery described above, the insulating member has an inclination angle of the inclined surfaces of the first and second inclined portions with respect to the stacking direction in the range of 30 ° to 60 °, respectively. Is preferred. If the inclination angle of the inclined surfaces of the first and second inclined portions is too small or too large, the electrode tab may be broken due to a load applied to the electrode tab when the electrode body is inserted. Because.

  ADVANTAGE OF THE INVENTION According to this invention, the secondary battery by which damage to the electrode plate and separator in an electrode body was prevented is provided.

It is a front view of the battery which concerns on this form. It is sectional drawing in the position of the positive electrode terminal of a battery. It is a figure for demonstrating the negative electrode plate, positive electrode plate, and separator which comprise an electrode body. It is a perspective view of an insulating member. It is a figure which shows the electrode body before an insulating member is assembled | attached. It is a figure for demonstrating the insulating member assembly | attachment process of this form. It is a figure for demonstrating the assembly body structure process of this form. It is a figure for demonstrating the terminal connection process of this form. It is a figure for demonstrating the insertion process of this form. It is a figure for demonstrating the modification of an assembly | attachment process. It is a figure for demonstrating the modification in the case of performing an insulating member assembly | attachment process after a terminal connection process. It is a figure for demonstrating the modification of an insulating member. It is a figure for demonstrating a wound type electrode body.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the best mode for embodying the present invention will be described in detail with reference to the drawings. In this embodiment, the present invention is applied to a lithium ion secondary battery having a stacked electrode body.

  1 and 2 show cross-sectional views of a battery 100 according to this embodiment. 2 is a cross-sectional view taken along the line XX shown in FIG. 1 is a cross-sectional view at the YY position shown in FIG. As shown in FIG. 1, the battery 100 is a lithium ion secondary battery in which an electrode body 110 and an electrolytic solution 101 are accommodated in a battery case 102. The electrolytic solution 101 is made of an organic solvent in which a lithium salt is dissolved. The battery case 102 includes a case main body 103 and a sealing member 104. Further, the sealing member 104 includes a gasket 105 that is an insulating member.

  FIG. 3 is a diagram illustrating the positive electrode plate 120, the negative electrode plate 130, and the separator 140 that constitute the electrode body 110. As shown in FIG. 3, the positive electrode plate 120 is formed by forming a positive electrode active material layer 122 on both surfaces of a positive electrode current collector foil 121 using a positive electrode material such as a positive electrode active material or a binder. Moreover, the positive electrode plate 120 has the positive electrode protrusion part 123 which is not formed with the positive electrode active material layer 122 and protrudes upward from the part where the positive electrode active material layer 122 is formed. Since the positive electrode active material layer 122 is not formed in the positive electrode protrusion 123, the positive electrode current collector foil 121 is exposed.

  The negative electrode plate 130 is formed by forming a negative electrode active material layer 132 on both surfaces of a negative electrode current collector foil 131 using a negative electrode material such as a negative electrode active material or a binder. Further, the negative electrode plate 130 has a negative electrode protruding portion 133 that is not formed with the negative electrode active material layer 132 and protrudes upward from a portion where the negative electrode active material layer 132 is formed. Since the negative electrode active material layer 132 is not formed on the negative electrode protrusion 133, the negative electrode current collector foil 131 is exposed.

  Both the portion of the positive electrode plate 120 where the positive electrode active material layer 122 is formed and the portion of the negative electrode plate 130 where the negative electrode active material layer 132 is formed contain an active material. For this reason, the formation part of the positive electrode active material layer 122 of the positive electrode plate 120 and the formation part of the negative electrode active material layer 132 of the negative electrode plate 130 are charging / discharging parts that contribute to charging / discharging in the battery 100. The separator 140 is a sheet-like porous member.

  The electrode body 110 of this embodiment shown in FIGS. 1 and 2 is formed by laminating a plurality of positive plates 120, negative plates 130, and separators 140. Specifically, it is a stacked electrode body in which a plurality of positive plates 120 and negative plates 130 are stacked by flat stacking with a separator 140 interposed therebetween. Further, as shown in FIG. 3, the positive electrode plate 120 and the negative electrode plate 130 in the electrode body 110 are laminated so as to overlap each other at the charge / discharge portion where the positive electrode active material layer 122 and the negative electrode active material layer 132 are formed. .

  As a result, the electrode body 110 has a laminated portion 111 in which the charge / discharge portions where the positive electrode active material layer 122 and the negative electrode active material layer 132 of the positive electrode plate 120 and the negative electrode plate 130 are formed overlap each other with the separator 140 interposed therebetween. ing. When the battery 100 is charged and discharged, the stacking unit 111 exchanges lithium ions between the positive electrode plate 120 and the negative electrode plate 130 via the electrolytic solution 101 held in the pores of the separator 140 that is a porous member. It is a part to do.

  In the present embodiment, the surface excluding the surface located at the end in the stacking direction among the outer surfaces of the stacked section 111 of the electrode body 110 is defined as the side surface of the stacked section 111. In FIG. 1 and FIG. 2, among the side surfaces of the stacked portion 111, the upper side surface is shown as the upper surface 112, and the lower side surface is shown as the lower surface 113. Further, the side surfaces of the laminated portion 111 including the upper surface 112 and the lower surface 113 are each constituted by the end portions of the positive electrode plate 120, the negative electrode plate 130, and the separator 140 laminated on the electrode body 110.

  In the electrode body 110, as shown in FIG. 1, a plurality of positive electrode protrusions 123 and negative electrode protrusions 133 protrude upward from the upper surface 112 of the stacked part 111. Further, the plurality of positive electrode protruding portions 123 protruding from the stacked portion 111 constitute a positive electrode tab 150 by being bundled. The plurality of negative electrode protrusions 133 protruding from the stacked portion 111 are also bundled to form the negative electrode tab 160.

  As shown in FIG. 2, the positive electrode tab 150 is connected to the connection end 126 of the positive electrode terminal 125 at a connection portion 151 near the protruding tip. The negative electrode tab 160 is also connected to the connection end 136 of the negative electrode terminal 135 at a connection portion 161 near the protruding tip as shown in parentheses in FIG.

  The positive terminal 125 has an exposed end 127 opposite to the connection end 126 connected to the positive electrode tab 150 exposed to the outside of the battery case 102 via the gasket 105. Also for the negative electrode terminal 135, an exposed end 137 opposite to the connection end 136 connected to the negative electrode tab 160 is exposed to the outside of the battery case 102 through the gasket 105. The battery 100 performs charging and discharging in the stacked portion 111 of the electrode body 110 via the positive electrode terminal 125 and the negative electrode terminal 135.

  Here, as shown in FIG. 2, the positive electrode tab 150 of this embodiment has a positive electrode tab inclined portion 152 between the connection location 151 and the laminated portion 111. The positive electrode tab inclined portion 152 is a portion that is inclined such that the outer surfaces of the plurality of positive electrode protruding portions 123 in the stacking direction become narrower as the portion farther from the stacked portion 111. As for the negative electrode tab 160, as shown in parentheses in FIG. 2, the portion on the outer side in the stacking direction of the negative electrode protruding portion 133 between the connection portion 161 and the stacked portion 111 is closer to the stacked portion 111. The negative electrode tab inclined portion 162 is inclined so as to be narrowed.

  Further, as shown in FIGS. 1 and 2, the battery 100 of this embodiment includes an insulating member 170 in which a positive electrode tab 150 and a negative electrode tab 160 are assembled. The insulating member 170 in this embodiment is made of polypropylene (PP) that is an insulating material. FIG. 4 is a perspective view of the insulating member 170.

  As shown in FIG. 4, the insulating member 170 has inclined portions 171 and 173 facing each other. As shown in FIG. 4, the inclined portion 171 and the inclined portion 173 are formed so as to protrude toward the front side from the connecting portion 175 on the back side. A gap A is provided between the inclined portion 171 and the inclined portion 173. The gap A is narrower than the thickness of the stacked portion 111 of the electrode body 110 in the stacking direction.

  As shown in FIG. 4, the inclined portion 171 has an inclined surface 172 on the surface facing the inclined portion 173. The inclined surface 172 is inclined in a direction away from the inclined portion 173 toward the lower side which is the tip side of the inclined portion 171.

  Further, an inclined surface 174 is formed on the inclined portion 173 on the surface facing the inclined portion 171. The inclined surface 174 is inclined in a direction away from the inclined portion 171 toward the lower side which is the tip side of the inclined portion 173. That is, the inclined surfaces 172 and 174 are surfaces that are inclined away from the other side toward the distal end side of the inclined portions 171 and 173, respectively.

  Further, the insulating member 170 has a connecting portion 176 extending upward from the left inclined portion 173 in FIG. An end surface 178 is formed on the upper surface of the connecting portion 176. The end surface 178 is a surface formed at the other end with respect to the inclined portions 171 and 173 provided at one end of the insulating member 170.

  Further, the connection portion 176 is formed with a through hole 177 penetrating the connection portion 176 in the thickness direction. The through hole 177 of the insulating member 170 is formed at a position corresponding to the connection portion 151 of the positive electrode tab 150 when the insulating member 170 is assembled to the positive electrode tab 150. Further, the position of the through hole 177 of the insulating member 170 is formed at a position corresponding to the connection portion 161 of the negative electrode tab 160 when assembled to the negative electrode tab 160.

  As shown in FIG. 2, the insulating member 170 is assembled to the positive electrode tab 150 and the negative electrode tab 160 with the inclined portions 171 and 173 facing downward. Specifically, the insulating member 170 is assembled to the positive electrode tab 150 and the negative electrode tab 160 with the inclined portions 171 and 173 facing the laminated portion 111 of the electrode body 110, respectively.

  Insulating member 170 sandwiches positive electrode tab inclined portion 152 and negative electrode tab inclined portion 162 from both outer surfaces by inclined surface 172 of inclined portion 171 and inclined surface 174 of inclined portion 173. Therefore, the inclined surfaces 172 and 174 are in contact with the inclined outer surfaces of the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162, respectively.

  The insulating member 170 passes through the positive electrode tab 150 in the gap A between the inclined portion 171 and the inclined portion 173. The insulating member 170 projects the connection portion 151 of the positive electrode tab 150 toward the end surface 178 located at the other end opposite to the inclined portions 171 and 173. Also on the negative electrode tab 160 side, the negative electrode tab 160 is passed through the gap A between the inclined portion 171 and the inclined portion 173, and the connection portion 161 protrudes toward the end surface 178 at the other end opposite to the inclined portions 171 and 173. I am letting.

  Further, in the insulating member 170 of this embodiment, the end surface 178 is in contact with the lower surface that is the inner surface of the sealing member 104. On the other hand, as described above, the inclined surfaces 172 and 174 opposite to the end surface 178 are in contact with the inclined outer surfaces of the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162, respectively. For this reason, the insulating member 170 is sandwiched between both the outer surfaces of the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162 and the sealing member 104. Since the insulating member 170 is insulative, insulation between the battery case 102 and the electrode body 110 is ensured.

  Further, FIG. 2 shows an angle θ of the inclined surfaces 172 and 174 of the inclined portions 171 and 173 with respect to the stacking direction of the electrode body 110. In the insulating member 170 of this embodiment, the inclined surfaces 172 and 174 are formed so that the angle θ is in the range of 30 ° to 60 °. Details of this will be described later.

Next, a method for manufacturing the battery 100 of this embodiment will be described. The manufacturing procedure of the battery 100 of this embodiment is shown below.
1. 1. Electrode body manufacturing process Assembly process 3. Insertion process

  First, in “1. Electrode body manufacturing process”, the electrode body 110 is manufactured by laminating the positive electrode plate 120, the negative electrode plate 130, and the separator 140 by flat stacking. As shown in FIG. 3, the positive electrode plate 120 used in this step has a positive electrode active material layer 122 and a positive electrode protrusion 123 already formed thereon. As the negative electrode plate 130, as shown in FIG. 3, the negative electrode active material layer 132 and the negative electrode protrusion 133 already formed are used. In this step, the electrode body 110 is formed such that the charge / discharge part in which the positive electrode active material layer 122 and the negative electrode active material layer 132 of the positive electrode plate 120 and the negative electrode plate 130 are formed is stacked on the stacked portion 111 of the electrode body 110. Are stacked.

  Further, in this process, as the positive electrode plate 120, the one having the positive electrode protrusion 123 formed at the position shown in FIG. 3 is used. Also for the negative electrode plate 130, the one having the negative electrode protrusion 133 formed at the position shown in FIG. 3 is used. That is, as shown in FIG. 3, the formation position of the positive electrode protrusion 123 of the positive electrode plate 120 and the formation position of the negative electrode protrusion 133 of the negative electrode plate 130 are different positions. In the stacking in this step, the positive electrode protruding portion 123 of the positive electrode plate 120 and the negative electrode protruding portion 133 of the negative electrode plate 130 are both protruded from the upper surface 112 of the stacked portion 111.

  Therefore, as a result of the lamination in this step, all of the positive electrode protrusions 123 of the positive electrode plate 120 protrude from the same position on the upper surface 112 of the lamination part 111 when viewed from the lamination direction. The positive electrode tab 150 is formed by the plurality of positive electrode protruding portions 123 protruding from the stacked portion 111. Further, the negative electrode plate 130 is also in a state in which the negative electrode protruding portion 133 protrudes from the same position on the upper surface 112 of the stacked portion 111 when viewed from the stacking direction. Therefore, the negative electrode tab 160 is also formed on the negative electrode plate 130 by the plurality of negative electrode protrusions 133 protruding from the stacked portion 111.

  Next, “2. Assembly process” is performed. In this step, the sealing member 104, the electrode body 110, the positive electrode terminal 125, the negative electrode terminal 135, and the insulating member 170 are assembled to produce these assemblies.

Further, in the assembly process of this embodiment, the assembly is manufactured by the following procedure.
2-1. Insulating member assembly step 2-2. Assembly structure configuration process 2-3. Terminal connection process

  “2. Assembly process” of this embodiment will be described in the above order. First, in “2-1. Insulating member assembling step”, the insulating member 170 is assembled to the electrode body 110. FIG. 5 is a side view of the electrode body 110 before the insulating member 170 is assembled. That is, the electrode body 110 shown in FIG. 5 is manufactured in an electrode body manufacturing process in which the positive electrode plate 120, the negative electrode plate 130, and the separator 140 are stacked.

  In FIG. 5, the electrode body 110 has the upper surface 112 from which the positive electrode tab 150 and the negative electrode tab 160 protrude facing upward. An insulating member 170 is shown above the electrode body 110. The insulating member 170 shown in FIG. 5 has the end of the end having the inclined portions 171 and 173 facing the electrode body 110.

  In the insulating member assembling step, the insulating member 170 is assembled to the positive electrode tab 150 and the negative electrode tab 160 by moving the insulating member 170 downward from the state shown in FIG. In addition to moving the insulating member 170 downward, the electrode body 110 may be moved upward. Alternatively, the insulating member 170 and the electrode body 110 may be moved toward each other. FIG. 6 shows the electrode body 110 with the insulating member 170 assembled thereto.

  As shown in FIG. 6, the insulating member 170 is assembled to the positive electrode tab 150 and the negative electrode tab 160 of the electrode body 110 with the leading ends of the inclined portions 171 and 173 facing the laminated portion 111 of the electrode body 110. . Specifically, with respect to the positive electrode tab 150, the insulating member 170 is assembled so as to be sandwiched between the inclined portion 171 and the inclined portion 173 at a position close to the base of the positive electrode tab 150 protruding from the stacked portion 111. That is, the position of the positive electrode tab 150 sandwiched between the inclined portions 171 and 173 of the insulating member 170 is a position between the connection portion 151 to which the positive electrode terminal 125 is connected and the stacked portion 111.

  Further, the insulating member 170 sandwiches the positive electrode tab 150 from the outside in the stacking direction by the inclined surface 172 of the inclined portion 171 and the inclined surface 174 of the inclined portion 173. Due to the sandwiching between the inclined portions 171 and 173, the positive electrode tab 150 is formed with a positive electrode tab inclined portion 152 that is deformed into a shape along the inclined surfaces 172 and 174.

  In the positive electrode tab inclined portion 152, the positive electrode protruding portions 123 constituting the positive electrode tab 150 are pressed toward each other as the position is farther from the stacked portion 111. That is, by forming the positive electrode tab inclined portion 152, the positive electrode protruding portions 123 of the positive electrode tab 150 are gathered toward the inner side in the stacking direction as the position is farther from the stacked portion 111. For this reason, both surfaces of the positive electrode tab inclined portion 152 on the outer side in the stacking direction are tilted in such a direction that the portion farther from the stacking section 111 becomes narrower.

  Furthermore, the insulating member 170 is assembled so that the positive electrode tab 150 passes through the gap A between the inclined portion 171 and the inclined portion 173. For this reason, the connection part 151 of the positive electrode tab 150 protrudes from the inclined parts 171 and 173 toward the end surface 178 which is the end opposite to the inclined parts 171 and 173.

  The insulating member 170 is assembled to the negative electrode tab 160 in the same manner as the positive electrode tab 150. That is, the insulating member 170 is disposed between the inclined portions 171 and 173 at a position between the connection portion 161 of the negative electrode tab 160 and the laminated portion 111 with the leading ends of the inclined portions 171 and 173 facing the laminated portion 111. The inclined surfaces 172 and 174 sandwich the outer side in the stacking direction. As a result, the negative electrode tab 160 is formed with a negative electrode tab inclined portion 162 deformed into a shape along the inclined surfaces 172 and 174. In addition, the insulating member 170 has a negative electrode tab 160 projecting through the gap A between the inclined portions 171 and 173 so that the connection portion 161 protrudes toward the end surface 178 opposite to the inclined portions 171 and 173. The tab 160 is assembled.

  Further, the connection portion 151 of the positive electrode tab 150 is on the front end side in the protruding direction with respect to the positive electrode tab inclined portion 152 formed by assembling the insulating member 170. The connecting portion 161 of the negative electrode tab 160 is also on the front end side in the protruding direction with respect to the negative electrode tab inclined portion 162 formed by assembling the insulating member 170. For this reason, the thickness of the connecting portions 151 and 161 of the positive electrode tab 150 and the negative electrode tab 160 in the stacking direction is set to be thinner than the thickness of the stacked portion 111. This is because the gap A between the inclined portions 171 and 173 is narrower than the thickness of the stacked portion 111 as described above.

  Next, in the assembly process, “2-2. In the assembly configuration process of this embodiment, the electrode body 110 assembled with the insulating member 170 and the sealing member 104 assembled with the positive electrode terminal 125 and the negative electrode terminal 135 are assembled. That is, in this embodiment, the positive electrode terminal 125 and the negative electrode terminal 135 are assembled in advance to the sealing member 104 as shown in FIG.

  As shown in FIG. 7, the positive terminal 125 is assembled to the sealing member 104 so that the connecting end 126 protrudes downward and the exposed end 127 protrudes upward. The lower surface, which is the lower surface of the sealing member 104, is the inner surface of the battery case 102. The upper surface, which is the upper surface of the sealing member 104, is a surface that is the outside of the battery case 102. That is, the positive terminal 125 is assembled to the sealing member 104 such that the connection end 126 protrudes from the inner surface side of the sealing member 104 and the exposed end 127 protrudes from the outer surface side of the sealing member 104.

  Similarly to the positive electrode terminal 125, the negative electrode terminal 135 is assembled to the sealing member 104 so that the connection end 136 protrudes from the inner surface side of the sealing member 104 and the exposed end 137 protrudes from the outer surface side of the sealing member 104. Gaskets 105 are assembled between the positive terminal 125 and the negative terminal 135 and the sealing member 104, respectively.

  Then, the sealing member 104 to which the positive electrode terminal 125 and the negative electrode terminal 135 are assembled is moved in the direction indicated by the arrow in FIG. Specifically, the assembly is performed such that the connection end 151 of the positive electrode terminal 125 and the connection portion 151 of the positive electrode tab 150 and the connection end 136 of the negative electrode terminal 135 and the connection portion 161 of the negative electrode tab 160 are overlapped. Further, the sealing member 104 is assembled so that the lower surface on the inner surface side of the sealing member 104 contacts the end surface 178 of the insulating member 170. The state after the assembly is shown in FIG.

  As shown in FIG. 8, since the lower surface of the sealing member 104 is assembled so as to come into contact with the end surface 178 of the insulating member 170, the insulating member 170 has the sealing member 104 and the positive electrode tab inclined portion 152 or the sealing member 104. And the negative electrode tab inclined portion 162. As described above, the insulating member 170 sandwiches both the outer surfaces of the positive electrode tab inclined portion 152 or the negative electrode tab inclined portion 162 in the stacking direction between the inclined surfaces 172 and 174 of the inclined portions 171 and 173. Thereby, the assembly 190 in which the sealing member 104, the electrode body 110, the insulating member 170, the positive terminal 125, and the negative terminal 135 are assembled is configured. Note that the end surface 178 of the insulating member 170 may be joined to the lower surface of the sealing member 104.

  Then, in the assembly process, “2-3. Terminal connection process” is performed in the state shown in FIG. In this embodiment, the terminal connection process is performed by resistance welding. Specifically, as shown in FIG. 8, the connection end 126 of the positive electrode terminal 125 and the connection portion 151 of the positive electrode tab 150 are sandwiched by welding jigs 180 and 181 from both sides in the stacking direction.

  During this clamping, the welding jig 181 on the positive electrode terminal 125 side can be brought into contact with the connection end 126 of the positive electrode terminal 125 by passing through the through hole 177 of the insulating member 170. Further, energization is performed between the welding jigs 180 and 181 in a sandwiched state, and the connection end 126 of the positive electrode terminal 125 and the connection portion 151 of the positive electrode tab 150 are joined.

  Similarly, on the negative electrode terminal 135 side, the connection portion 161 of the connection end 136 and the negative electrode tab 160 is energized between them while being sandwiched by the welding jigs 180 and 181 from both sides in the stacking direction. Thereby, the connection end 136 of the negative electrode terminal 135 and the connection part 161 of the negative electrode tab 160 are joined. Note that this process can be performed not only by resistance welding but also by ultrasonic welding.

  Next, “3. Insertion process” is performed. In this step, the electrode body 110 is inserted into the case body 103 out of the assembly 190 in which the sealing member 104, the electrode body 110, the insulating member 170, the positive electrode terminal 125, and the negative electrode terminal 135 are assembled. This process will be described with reference to FIG.

  As shown in FIG. 9, the assembly 190 is arranged with the lower surface 113 of the electrode body 110 facing the opening 106 of the case body 103. Then, in the state of FIG. 9, the upper surface that is the outer surface side of the sealing member 104 is pressed toward the inside of the case main body 103. That is, the direction of the pressing load applied to the upper surface of the sealing member 104 is downward in FIG. By this pressing, the electrode body 110 of the assembly 190 can be inserted into the case main body 103 from the lower surface 113 thereof. In the insertion step, a load is applied until the opening 106 of the case main body 103 is closed by the lower surface which is the inner surface side of the sealing member 104.

  Here, in this embodiment, this insertion step can be performed without damaging the electrode body 110. This is because the electrode body 110 of this embodiment can receive a pressing load on the upper surface of the sealing member 104 by the positive electrode tab inclined portion 152 of the positive electrode tab 150 and the negative electrode tab inclined portion 162 of the negative electrode tab 160.

  That is, the pressing load on the upper surface of the sealing member 104 is applied to the electrode body 110 through the insulating member 170 that is in contact with the lower surface of the sealing member 104. The pressing from the sealing member 104 received by the end surface 178 of the insulating member 170 is also downward in FIG. Therefore, the insulating member 170 presses the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162 downward in FIG. 9 by the inclined surfaces 172 and 174 of the inclined portions 171 and 173 by the pressing load received by the end surface 178 thereof. . Thereby, the electrode body 110 of this embodiment can receive the pressing load in the insertion process by the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162.

  A larger pressing load can be applied to the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162 than to the upper surface 112 of the stacked portion 111. In this embodiment, even if a large pressing load is applied to the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162, the positive electrode plate 120 and the negative electrode plate 130 are prevented from being broken or torn.

  As described above, the upper surface 112, which is the side surface of the stacked portion 111, is configured by the positive electrode plate 120, the negative electrode plate 130, and the end portions of the separator 140. The positive electrode plate 120, the negative electrode plate 130, and the separator 140 are all thin foils. Therefore, when a force is applied to the upper surface 112 of the stacked portion 111, the end portions of the positive electrode plate 120, the negative electrode plate 130, and the separator 140 constituting the upper surface 112 are likely to be damaged or broken.

  On the other hand, in the present embodiment, the ends of the positive electrode plate 120, the negative electrode plate 130, and the separator 140 are exposed to the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162 that receive a pressing load by the inclined surfaces 172 and 174 of the inclined portions 171 and 173. Not done. For this reason, the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162 can receive a large pressing load while suppressing damage to the positive electrode plate 120 and the negative electrode plate 130.

  Further, in the positive electrode tab inclined portion 152, a plurality of positive electrodes constituting the positive electrode tab inclined portion 152 are caused by the downward pressing load by the inclined surfaces 172 and 174 of the inclined portions 171 and 173 corresponding to the inclination. The protrusion 123 can be received in the thickness direction. The negative electrode tab inclined portion 162 also has a plurality of negative electrode protrusions constituting the negative electrode tab inclined portion 162 corresponding to the downward pressing load by the inclined surfaces 172 and 174 of the inclined portions 171 and 173 by the amount of inclination. 133 in the thickness direction.

  The inclined surfaces 172 and 174 of the inclined portions 171 and 173 are inclined away from each other toward the lower end side in FIG. Further, the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162 are inclined in such a direction that the upper portion in FIG. That is, with respect to the downward pressing in FIG. 9 received by the insulating member 170, the inclined surfaces 172 and 174 of the inclined portions 171 and 173, the positive electrode protruding portion 123 of the positive electrode tab inclined portion 152 and the negative electrode protruding portion 133 of the negative electrode tab inclined portion 162. This is because is inclined.

  And the positive electrode tab inclination part 152 comprised by the lamination | stacking of the some positive electrode protrusion part 123 is a high intensity | strength with respect to the press of the thickness direction of the positive electrode protrusion part 123. As shown in FIG. For this reason, the positive electrode protruding portion 123 constituting the positive electrode tab inclined portion 152 is less likely to be broken or torn due to the pressing load by the inclined surfaces 172 and 174 of the inclined portions 171 and 173.

  Since the negative electrode tab inclined part 162 is also configured by stacking a plurality of negative electrode protrusions 133, the negative electrode tab inclination part 162 has high strength against the pressing load in the thickness direction of the negative electrode protrusions 133. For this reason, the negative electrode tab inclined part 162 is also less likely to be broken or torn in the negative electrode protruding part 133 due to the pressing load by the inclined surfaces 172 and 174 of the inclined parts 171 and 173.

  Therefore, in this embodiment, the insertion step can be performed without damaging the positive electrode plate 120, the negative electrode plate 130, and the separator 140 that constitute the electrode body 110. That is, the assembly 190 is manufactured by assembling the insulating member 170 and the like in the assembly process in the electrode assembly 110 manufactured by the electrode assembly manufacturing process. In the insertion step, the electrode body 110 of the assembly 190 is inserted into the case body 103 without damaging the positive electrode plate 120, the negative electrode plate 130, and the separator 140 that constitute the electrode body 110. The battery 100 can be manufactured.

  In addition, the case main body 103 and the sealing member 104 of the battery case 102 are joined after an insertion process. In addition, the electrolytic solution 101 is injected into the battery case 102. The electrolyte solution 101 may be injected into the case body 103 in advance before the insertion process. Or you may inject | pour the electrolyte solution 101 with an insertion process. Alternatively, for example, the sealing member 104 may be provided with an injection port, and after the case body 103 and the sealing member 104 are joined, the electrolyte solution 101 may be injected from the injection port.

  Further, as described above, in the insulating member 170 of this embodiment, the inclined surfaces 172 and 174 are formed so that the angle θ with respect to the stacking direction of the electrode body 110 is in the range of 30 ° or more and 60 ° or less. . By forming the inclined surfaces 172 and 174 in this way, damage to the positive electrode tab 150 or the negative electrode tab 160 when the insulating member 170 is assembled to the positive electrode tab 150 or the negative electrode tab 160 can be suppressed. Furthermore, the pressing load in the insertion process can be applied to the electrode body 110 appropriately.

  That is, when the angle θ of the inclined surfaces 172 and 174 is too small, the positive electrode tab 150 or the negative electrode tab 160 is excessively deformed when the insulating member 170 is assembled. This is because the positive electrode protrusion 123 constituting the positive electrode tab 150 or the negative electrode protrusion 133 constituting the negative electrode tab 160 may be broken and broken. On the other hand, if the angle θ of the inclined surfaces 172 and 174 is too large, the pressing load in the insertion process may not be appropriately applied to the positive electrode tab inclined portion 152 or the negative electrode tab inclined portion 162.

  Moreover, in the assembly process of this embodiment, as described above, the insulating member assembly process is performed before the terminal connection process. Specifically, after the insulating member 170 is assembled to the positive electrode tab 150, the connection end 126 of the positive electrode terminal 125 and the connection portion 151 of the positive electrode tab 150 are joined. As shown in FIG. 6, the positive electrode tab 150 has the connection portions 151 gathered in the stacking direction by assembling the insulating member 170.

  That is, by connecting the insulating member 170, the positive electrode tab 150 is formed with a connection portion 151 for connecting the positive electrode terminal 125. For this reason, when performing a terminal connection process, the special structure which collects the front end side of the protrusion direction of the positive electrode tab 150 and forms the connection location 151 is unnecessary. In this embodiment, the connection end 126 of the positive electrode terminal 125 can be overlapped and joined to the connection portion 151 of the positive electrode tab 150 formed by assembling the insulating member 170 as it is.

  Furthermore, since the insulating member 170 is assembled, displacement of the positive electrode protrusion 123 at the connection portion 151 of the positive electrode tab 150 is suppressed. In addition, the tension on the positive electrode tab 150 during welding is relaxed. Thereby, the assembly process can be efficiently performed while preventing the positive electrode protrusion 123 in the positive electrode tab 150 from being damaged. The same applies to the negative electrode terminal 135 and the negative electrode tab 160.

  Moreover, in said assembly | attachment process, the insulating member assembly | attachment process and the assembly | attachment body structure process are performed separately. However, the insulating member assembling process and the assembly structure process can be performed simultaneously. That is, as shown in FIG. 10, the end surface 178 of the insulating member 170 is bonded to the inner surface side of the sealing member 104 in advance, and the assembly 190 is assembled so that the insulating member 170 is assembled to the positive electrode tab 150 and the negative electrode tab 160. May be configured.

  It is also possible to perform a terminal connection process before the insulating member assembling process. A positive electrode terminal 125 is connected to the positive electrode tab 150 shown in FIG. 11 by performing the terminal connection process. And as shown in FIG. 11, the insulating member 170 can be assembled | attached between the connection location 151 of the positive electrode tab 150 to which the positive electrode terminal 125 is already connected, and the laminated part 111. FIG. Also in this case, the insertion process can be performed without damaging the positive electrode plate 120, the negative electrode plate 130, and the separator 140 of the electrode body 110. In this case, the insulating member 170 may not have the through hole 177 of the connecting portion 176. This is because the terminal connection process has already been performed.

  Further, as shown in FIG. 4, the insulating member 170 used in the battery 100 of the present embodiment is formed by connecting an inclined portion 171 and an inclined portion 173 by a connecting portion 175. However, as shown in the battery 200 of FIG. 12, two insulating members 270 and 280 each having inclined portions 271 and 281 at one end may be used as a pair.

  The two insulating members 270 and 280 used in the battery 200 are inclined surfaces that are inclined toward the opposite surfaces of the inclined portions 271 and 281 provided at one end and away from the other at the distal end side. 272, 282 are formed. Further, a gap A is provided between the inclined portions 271 and 281 facing each other. The insulating members 270 and 280 may also be made of an insulating material such as PP.

  Further, in the insulating members 270 and 280, the inclined surfaces 272 and 282 of the inclined portions 271 and 281 are in contact with both outer surfaces of the positive electrode tab inclined portion 152 in the stacking direction of the positive electrode tab 150. Furthermore, end surfaces 275 and 285 that are the other ends of the inclined portions 271 and 281 of the insulating members 270 and 280 are in contact with the lower surface that is the inner surface of the sealing member 104. The same applies to the insulating members 270 and 280 assembled on the negative electrode tab 160 side. Therefore, the insulating members 270 and 280 are sandwiched between both the outer surfaces of the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162 and the sealing member 104.

  The battery 200 shown in FIG. 12 is also manufactured without damaging the positive electrode plate 120, the negative electrode plate 130, and the separator 140 of the electrode body 110 by the procedure of the electrode body manufacturing process, the assembly process, and the insertion process described above. can do. This is because the pressing load on the outer surface of the sealing member 104 in the insertion step can be applied to the positive electrode tab inclined portion 152 and the negative electrode tab inclined portion 162 of the electrode body 110 by the insulating members 270 and 280. When the terminal connecting step is performed after the insulating member assembling step in the assembling step, the welding jig is passed through the through hole 274 of the connecting portion 273 of the insulating member 270 and the through hole 284 of the connecting portion 283 of the insulating member 280. Welding may be performed.

  In the above description, the electrode body 110 is described as a laminated type. However, the present invention can also be applied to the wound electrode body 310 shown in FIG. The electrode body 310 has a structure in which a long positive electrode plate and a negative electrode plate are laminated by winding in the longitudinal direction with a separator interposed therebetween. Further, in the electrode body 310, a positive electrode plate and a negative electrode plate each having a plurality of projecting portions at the end on the upper surface 312 side of the laminated portion 311 are used. An active material layer is formed on each of the portions that become the laminated portion 311 of the positive electrode plate and the negative electrode plate. The active material layer is not formed at the protruding portions of the positive electrode plate and the negative electrode plate, and the current collector foil is exposed.

  And the electrode body 310 has the positive electrode tab 350 comprised by the lamination | stacking in the state in which only the positive electrode protrusion part of the positive electrode plate protruded from the lamination | stacking part 311. FIG. That is, in the positive electrode tab 350, a plurality of positive electrode protrusions are stacked. Moreover, it has the negative electrode tab 360 comprised by the lamination | stacking in the state which only the negative electrode protrusion part of the negative electrode plate protruded from the lamination | stacking part 311. FIG. That is, in the negative electrode tab 360, a plurality of negative electrode protrusions are stacked. Both the positive electrode tab 350 and the negative electrode tab 360 protrude from the upper surface 312 of the stacked portion 311.

  The electrode body 310 can be used in place of the electrode body 110 of the batteries 100 and 200 described above. This is because the positive electrode tab 350 and the negative electrode tab 360 of the electrode body 310 are configured in the same manner as the positive electrode tab 150 and the negative electrode tab 160 of the electrode body 110, respectively.

  That is, for the electrode body 310, as with the electrode body 110, after the insulating member 170 or the insulating members 270 and 280 are assembled to the positive electrode tab 350 and the negative electrode tab 360, the lower surface 313 faces the opening 106 of the case body 103. What is necessary is just to perform the insertion process to insert. The insertion process can be performed by applying a pressing load to the upper surface of the sealing member 104. That is, since it is not necessary to apply a pressing load to the upper surface 312 of the stacked portion 311, damage to the electrode plate or the like of the stacked portion 311 can be suppressed. The electrode body 310 is a flat wound type, but can be applied to a wound electrode body wound in a cylindrical shape.

  As described above in detail, the battery according to this embodiment includes the positive electrode tab and the insulating member sandwiched between the negative electrode tab and the sealing member. In the insertion step, a pressing load can be applied to the positive electrode tab inclined portion of the positive electrode tab and the negative electrode tab inclined portion of the negative electrode tab by the insulating member. That is, the insertion step can be performed without applying a pressing load to the side surface of the laminated portion of the electrode body constituted by the end portions of the electrode plates and the like. Therefore, a secondary battery manufacturing method and a secondary battery in which the electrode plate and the separator in the electrode body are prevented from being damaged are realized.

  Note that this embodiment is merely an example, and does not limit the present invention. Accordingly, the present invention can naturally be improved and modified in various ways without departing from the gist thereof. For example, each of the electrode bodies described in the above embodiments has a configuration in which both the positive electrode tab and the negative electrode tab protrude from one side surface of the laminated portion. However, in the electrode body, it is sufficient that at least one of the positive electrode tab and the negative electrode tab protrudes from the side surface of the laminated portion. This is because the insertion process can be performed without applying a pressing load to the side surface of the electrode body by assembling the insulating member to the electrode tab protruding from the side surface of the laminated portion.

  For example, the end surface 178 of the insulating member 170 may be in contact with the positive electrode terminal 125 or the negative electrode terminal 135 instead of the sealing member 104. That is, the insulating member 170 may be sandwiched between the sealing member 104 and the positive electrode tab inclined portion 152 or the negative electrode tab inclined portion 162 via another member. This is because a pressing load in the insertion process can be applied to the insulating member 170. This is because the pressing load in the insertion step can be applied to the positive electrode tab inclined portion 152 or the negative electrode tab inclined portion 162 of the electrode body 110 via the insulating member 170. The same applies to the insulating members 270 and 280. The same applies to a battery using the electrode body 310.

  In addition, for example, the insulating members 170, 270, and 280 are not limited to PP, as long as the insulating property between the sealing member 104 and the electrode body can be ensured. That is, the insulating members 170, 270, and 280 may be formed of an insulating material only on the inclined surface of the inclined end portion, for example. Further, for example, the present invention can be applied to nickel hydride secondary batteries other than lithium ion secondary batteries.

DESCRIPTION OF SYMBOLS 100 Battery 102 Battery case 103 Case main body 104 Sealing member 110 Electrode body 111 Lamination | stacking part 112 Upper surface 113 Lower surface 120 Positive electrode plate 121 Positive electrode current collection foil 122 Positive electrode active material layer 125 Positive electrode terminal 126 Connection end 127 Exposed end 130 Negative electrode plate 131 Negative electrode current collection Foil 132 Negative electrode active material layer 135 Negative electrode terminal 136 Connection end 137 Exposed end 140 Separator 150 Positive electrode tab 151 Connection location 152 Positive electrode tab inclined portion 160 Negative electrode tab 161 Connection location 162 Negative electrode tab inclined portion 170 Insulating members 171 and 173 Inclined portions 172 and 174 Inclined surface 178 End surface 190 Assembly A Clearance

Claims (2)

An electrode body formed by laminating a positive and negative electrode plate formed by forming an active material layer on a current collector foil while sandwiching a separator therebetween,
A battery case that has a case body in which an opening is formed and a sealing member that closes the opening of the case body, and that houses the electrode body therein,
An electrode terminal which is assembled to the sealing member and has a connection end connected to the electrode body inside the battery case and an exposed end exposed to the outside of the battery case;
The electrode plate is
The active material layer is formed, and a charge / discharge part that is a part overlapping the other positive and negative electrode plate and the separator by lamination in the electrode body,
The active material layer is not formed and the current collector foil is exposed, and has a protruding portion that is a portion protruding from a part of the end portion of the charge / discharge portion,
The electrode body is
A laminated portion in which the charge / discharge portions of the positive and negative electrode plates are laminated together with the separator;
Only one of the positive and negative of the protruding portion of the electrode plate is configured to be bundled by stacking in a state of protruding from the stacked portion, and has an electrode tab connected to the connection end of the electrode terminal,
In the secondary battery that is housed in the battery case with the side surface of the stacked portion from which the electrode tab protrudes facing the sealing member,
First and second inclined portions, which are provided so as to face each other and have inclined surfaces that are inclined in a direction away from the other toward the tip side, are formed on the surfaces facing each other. Having an insulating member having one end while providing a gap between the second inclined portions;
The electrode tab is
Between the connection portion connected to the connection end of the electrode terminal and the stacked portion, both the outer sides of the protruding portion in the stacking direction are inclined so that the portion farther from the stacked portion narrows in the stacking direction. The electrode tab has an inclined portion,
The insulating member is
The stacking direction of the electrode tab inclined portion is determined by the inclined surfaces of the first and second inclined portions in a state where both the leading end sides of the first and second inclined portions are directed to the stacked portion. While sandwiching both sides of the outside,
The electrode tab extends through the gap between the first and second inclined portions, and the connection portion protrudes toward the other end opposite to the first and second inclined portions;
Further, the secondary battery is sandwiched between both sides of the electrode tab inclined portion outside in the stacking direction and the sealing member. The secondary battery according to claim 1,
The insulating member is characterized in that the inclined angles of the inclined surfaces of the first and second inclined portions with respect to the stacking direction are in the range of 30 ° or more and 60 ° or less, respectively. battery.

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