JP5023559B2 - Battery manufacturing method - Google Patents

Description

  The present invention relates to a battery manufacturing method.

In recent years, various secondary batteries have been proposed as power sources for portable devices and portable devices, and as power sources for electric vehicles and hybrid vehicles. Such a secondary battery includes a polar group (electrode laminate) having a plurality of positive electrode plates (first electrode plates) and negative electrode plates (second electrode plates), a positive electrode current collector plate (first current collector plate), And a negative electrode current collector plate. In the polar group, positive plates and negative plates are alternately stacked via separators. On one side of the power generation element, a positive electrode current collector plate is joined to each lead portion (first current collector lead portion) among a plurality of stacked positive electrode plates of the polar group, and electrically connected to these positive electrode plates. Is conducting. Further, on the other side of the power generation element, a negative electrode current collector plate is joined to each lead portion of the plurality of negative electrode plates, and is electrically connected to these negative electrode plates. That is, each of the positive electrode current collector plate and the negative electrode current collector plate serves as an electrode terminal of a unit cell (see, for example, Patent Document 1).
JP 2001-297755 A

By the way, in the process of joining the current collector plate (positive electrode current collector plate, negative electrode current collector plate) to the lead portion of the electrode plate (positive electrode plate, negative electrode plate), positioning for positioning them on the current collector plate or lead portion. There was no portion, and the current collector plate and the lead portion were aligned and joined using a dedicated device or jig.
For this reason, due to the operation performance of the dedicated device, the dimensional accuracy of the jig, and the like, the lead portion may not be positioned at an appropriate position on the current collector plate. Even after the lead part and the current collector plate are positioned, when the current collector plate is joined to the lead part, the current collector plate is fixed with another jig. As a result, the current collector plate may move, and the joining position on the current collector plate may be displaced from the lead portion.
As a result, the current collector plate and the lead portion of the electrode plate cannot be joined to each other at the place where the current collector plate is to be joined, and this power generation element may become a defective product. Alternatively, since the lead portion of the electrode plate is not joined at an appropriate position on the joining surface of the current collector plate, the joined portion between the current collector plate and the electrode plate is broken, and the current collector plate and the electrode are There was a possibility that the plate would be separated and the conduction resistance of both would increase.

  The present invention has been made in view of the current situation, and in a battery in which lead portions of a plurality of electrode plates and current collector plates are joined, the current collector plates and the electrode plates are joined at appropriate positions. An object of the present invention is to provide a method for manufacturing a highly reliable battery.

The solution is an electrode laminate in which first electrode plates and second electrode plates are alternately laminated via separators, and the first electrode plate has a rectangular flat plate shape that holds an active material. An electrode including an electrode part and a rectangular plate-shaped first current collecting lead part that extends from a peripheral edge of one long side of the electrode part and is integrated with the electrode part and collects electric charges generated in the electrode part. and laminate to each of the first electrode plate, only in the first current collector lead section of that, and, a first collector plate formed by welding one or a plurality of welding portions, the power generating element having A method of manufacturing a battery comprising: the first current collecting lead portion and the first current collecting plate of at least one of the first electrode plates among the plurality of first electrode plates included in the electrode laminate. At least one of the first current collecting plate and the first current collecting lead of the first electrode plate And a part engaged, the first for positioning the positioning direction along the long sides of the current collector lead section has a positioning portion, the positioning portion, the first electrode plate of said first collector lead A convex lead-side positioning part provided on the first current collecting plate, a convex current-collecting side positioning part provided on the first current collecting plate, a convex current collecting side positioning part provided on the first current collecting plate, and A concave lead-side positioning part that can be fitted and engaged, or a concave current-collecting side positioning part provided on the first current collector plate and a convex lead-side positioning part that can be fitted and engaged therewith Yes, and the electrode stack and the first collector plate, a positioning step of positioning by the positioning unit, in a state of being positioned by the positioning step, the first collector plate, each at the welding site A welding step of welding to the first current collecting lead portion of the first electrode plate. That is a method for producing a battery.

In the battery manufacturing method of the present invention, at least one of the first current collecting lead and the first current collecting plate of at least one of the plurality of first electrode plates included in the electrode stack is at least one of the first current collecting plates. The positioning part is provided. And by this positioning part, an electrode laminated body and a 1st current collector plate are positioned, and each 1st electrode plate is welded to a 1st current collector plate.
For this reason, when welding the first current collecting plate and the first current collecting lead portion of each first electrode plate, a direction along the periphery of the first current collecting lead portion and along the first current collecting plate (specifically, In this case, it is possible to prevent misalignment in the direction along the long side of the rectangular first current collecting lead portion and to weld to an appropriate position.

The first current collector lead section, when metal contacts are of rectangular shape include embodiments that protrudes from a part or all of one long side of them.

Further, the positioning direction along the first current collecting lead portion and along the first current collecting plate refers to the periphery of the first current collecting lead portion along the first current collecting plate. And a direction along the first current collector plate. Thus, the first current collecting lead portion protruding from the electrodes unit is a rectangular shape, a battery arranged to be along the one long side of which the first current collector plate, the above-described first current collector lead section The direction along the long side corresponds.

  Further, the positioning part may be provided in at least one of the first current collecting lead part and the first current collecting plate of at least one of the plurality of first electrode plates included in the electrode laminate. That is, it may be formed on the first current collector plate, or may be formed on the first current collector lead portion of any one of the plurality of first electrode plates. Moreover, you may form in both the 1st current collection plate and the 1st current collection lead part of the 1st electrode plate.

  Specifically, the positioning part (collecting side positioning part) is formed only on the first current collecting plate, and the current collecting side positioning part is engaged with the first current collecting lead part of the first electrode plate for positioning. What to do is mentioned. In addition, a positioning part (lead side positioning part) is formed only on the first current collecting lead part of the first electrode plate, and positioning is performed by engaging the lead side positioning part with the first current collecting plate. . The first current collecting plate and the first current collecting lead portion of the first electrode plate are provided with positioning portions (current collecting side positioning portion and lead side positioning portion) that engage with each other, and these current collecting side positioning portions and There are also those that perform positioning by engaging the lead side positioning portions with each other.

  More specifically, for example, only on the first current collecting plate, two convex current collecting side positionings that can be engaged with both ends in the positioning direction of the first current collecting lead portions of the first electrode plate, respectively. The form which provides a part is mentioned. On the other hand, two convex lead-side positioning portions that can be engaged with both ends of the first current collector plate in the positioning direction only on the first current collector lead portion of the first electrode plate. The form which provides is also mentioned. Further, the first current collecting plate is provided with a convex current collecting side positioning portion, and the first current collecting lead portion of the first electrode plate is provided with a concave lead side positioning portion that can be fitted and engaged therewith. Alternatively, the first current collecting plate is provided with a concave current collecting side positioning portion, and the first current collecting lead portion of the first electrode plate is provided with a convex lead side positioning portion that can be engaged with the first current collecting plate. Is mentioned.

Furthermore, in the battery manufacturing method described above, the first current collector plate is the positioning portion, and the first current collector lead portion of the first electrode plate is disposed at both ends in the positioning direction. The first current collecting lead of at least one of the first electrode plates is a plurality of the first electrode plates among the plurality of first electrode plates. The first current collecting lead portion and the first current collecting plate of the first electrode plate are respectively engaged with the both end portions of the first portion and the two current collecting side positioning portions of the first current collecting plate. It is preferable to use a battery manufacturing method that positions the

In the battery manufacturing method of the present invention, two current-collecting side positioning portions are formed on the first current collecting plate, and in the positioning step, the first of at least one of the first electrode plates among the plurality of first electrode plates. Positioning is performed by engaging both end portions of the current collecting lead portion with the two current collecting side positioning portions of the first current collecting plate.
In this way, it is necessary to provide two current collecting side positioning portions on the first current collecting plate, but the first current collecting lead portion of the first electrode plate has a structural portion (for example, a concave portion) for positioning. Or protrusions). For this reason, in the 1st electrode plate, the structure of the 1st current collection lead part becomes simple, and it becomes easy to provide this 1st current collection lead part in the 1st electrode plate.

  Furthermore, in any one of the above-described battery manufacturing methods, the positioning portion or the current collecting side positioning portion is a bent portion formed by bending a part of the first current collecting plate in the plate thickness direction. It is preferable that the battery manufacturing method is a part.

  In the battery manufacturing method of the present invention, the positioning portion or the current collecting side positioning portion is configured by a bent portion in which a part of the first current collecting plate is bent in the thickness direction. Therefore, the positioning portion or the current collecting side positioning portion can be easily formed at a low cost.

  Further, in the battery manufacturing method described above, the bent portion of the first current collector plate is a plate of the first electrode plate in a state where the first current collector plate is welded to the first electrode plate. When viewed in the thickness direction, a method for manufacturing a battery that is smaller than the dimensions of the electrode laminate is preferable.

  In the battery manufacturing method of the present invention, when viewed in the thickness direction of the first electrode plate, that is, when viewed in the thickness direction of the electrode laminate, the dimension of the bent portion is made smaller than the dimension of the electrode laminate. The influence on the current flowing through the first current collector plate due to the provision of the bent portion can be suppressed.

  Next, an embodiment of the present invention will be described with reference to FIGS.

The secondary battery 100 according to this embodiment is a nickel-hydrogen secondary battery that can be used as a drive power source for electric vehicles and hybrid vehicles. The secondary battery 100 includes six power generation elements 110 each having an electrode stack 120, a positive current collector plate 150, and a negative current collector plate 250, and a battery case 180 having a case body member 181 and a lid member 186. (See FIG. 1). The case main body member 181 has a rectangular parallelepiped shape, and the internal space is divided by partition walls 182 to form six accommodating portions 183. Each power generation element 110 is accommodated together with the electrolytic solution in each accommodating portion 183 in the case main body member 181 and constitutes a unit cell.
Further, among the power generation elements 110 adjacent to each other, the power generation elements 110R and 110L (110) adjacent to each other, as shown in FIG. 2, the negative electrode current collector plate of one of the power generation elements 110L (110) (left side in FIG. 2). 250L (250) and the positive electrode current collector plate 150R (150) of the other power generation element 110R (110) (the right side in FIG. 2) are connected through a connection hole 184 provided in the partition wall 182 of the case body member 181. Yes. In this way, the six power generation elements 110 are connected to each other in series. The case body member 181 is closed with a lid member 186. Note that the secondary battery 100 corresponds to the battery of the present invention.

As shown in FIGS. 3 and 4, the power generation element 110 includes an electrode stack 120, a positive current collector 150, and a negative current collector 250. Among the power generation elements 110, the electrode stack 120 includes a large number of positive plates 130, negative plates 230, and bag-like separators 140, respectively. In this electrode laminate 120, the positive electrode plate 130 is inserted into a bag-like separator 140, and as shown in FIG. 4, the positive electrode plate 130 inserted into the separator 140 and the negative electrode plate 230 are alternately laminated. Has been.
As will be described in detail later, on one side of the power generation element 110, the positive electrode current collector plate 150 is disposed at one end portion (left end portion in FIG. 4) of each positive electrode plate 130 of the stacked electrode laminate 120. The positive electrode plate lead portion 132 is welded and electrically connected to the positive electrode plate 130. Similarly, on the other side of the power generation element 110, the negative electrode current collector plate 250 is a negative electrode plate disposed at the other end (the right end in FIG. 4) of each negative electrode plate 230 of the stacked electrode stack 120. The lead portion 232 is welded and electrically connected to the negative electrode plate 230.

Of the power generation element 110, the electrode stack 120 will be described.
FIG. 5 shows a perspective view of the electrode stack 120 from which the separator 140 is not shown. As described above, the electrode laminate 120 includes a large number of positive plates 130, negative plates 230, and separators 140.
In the electrode laminate 120, the positive electrode plate 130 is made of metal, and as shown in FIG. 5, a rectangular plate-shaped positive electrode plate electrode portion 131 holding a positive electrode active material, and the positive electrode plate electrode portion 131. It has a positive electrode plate lead part 132 that extends from the periphery, specifically, the long side 131a and is integrated therewith. Specifically, the positive electrode plate electrode portion 131 is a rectangular electrode portion in which a positive electrode active material containing nickel hydroxide is supported on an active material support such as foamed nickel.

On the other hand, the positive electrode plate lead portion 132 is made of a strip-shaped metal member that collects electric charges generated in the positive electrode plate electrode portion 131. The positive electrode plate lead portion 132 protrudes from a part of one long side 131a (the vertical direction side in FIG. 5) of the positive electrode plate electrode portion 131, and has a short side parallel to the short side of the positive electrode plate electrode portion 131 and the positive electrode. The plate electrode portion 131 has a rectangular shape having a long side parallel to the long side 131a. The positive electrode plate lead portion 132 has a positive electrode lead edge 132a having a long side and a side in the plate thickness direction. The positive electrode lead base end portion 132b and the positive electrode lead front end portion 132c, which are the ends on both sides of the positive electrode plate lead portion 132, are a base end side bent portion 156H and a front end side bent portion of the positive electrode current collector plate 150 described later. It is a site | part engaged with 156L. Jig insertion holes 133 (133A to 133D) are drilled in the same position in the positive electrode plate lead portion 132 of each positive electrode plate 130, respectively. The positive electrode plate 130 corresponds to the first electrode plate of the present invention, the positive electrode plate electrode portion 131 corresponds to the electrode portion of the present invention, and the positive electrode plate lead portion 132 corresponds to the first current collecting lead portion.
In the electrode laminate 120, each positive electrode plate 130 is laminated in a state where the positive electrode plate lead portions 132 are all arranged in the same direction and positioned.

  On the other hand, in the electrode laminate 120, the negative electrode plate 230 is also made of metal, and as shown in FIG. 5, a rectangular flat plate-shaped negative electrode plate electrode portion 231 holding a negative electrode active material, and the negative electrode plate electrode portion. It has a negative electrode plate lead portion 232 extending from the peripheral edge of 231, specifically, the long side 231 a and integrated therewith. Specifically, the negative electrode plate electrode portion 231 is a rectangular electrode portion including, for example, a hydrogen storage alloy as a negative electrode constituent material.

On the other hand, the negative electrode plate lead portion 232 is made of a strip-shaped metal member that collects electric charges generated in the negative electrode plate electrode portion 231. The negative electrode plate lead portion 232 protrudes from a part of one long side 231a (the vertical side in FIG. 5) of the negative electrode plate electrode portion 231, and has a short side parallel to the short side of the negative electrode plate electrode portion 231 and a negative electrode. The plate electrode portion 231 has a rectangular shape having a long side parallel to the long side 231a. The negative electrode plate lead portion 232 has a negative electrode lead edge 232 composed of a long side and a plate thickness direction side.
a. The negative electrode lead base end portion 232b and the negative electrode lead front end portion 232c, which are ends on both sides of the negative electrode plate lead portion 232, are a base end side bent portion 256H and a front end side bent portion of a negative electrode current collector plate 250 to be described later. It is a site | part engaged with 256L. Jig insertion holes 233 (233A to 233D) are drilled at the same positions in the negative electrode plate lead portions 232 of the respective negative electrode plates 230.
In the present embodiment, the negative electrode plate 230 corresponds to the second electrode plate of the present invention. The negative electrode plate 230 may correspond to the first electrode plate, and the positive electrode plate 130 may correspond to the second electrode plate.
In the electrode laminate 120, each negative electrode plate 230 is laminated in a state where the negative electrode plate lead portion 232 is disposed in the opposite direction to the positive electrode plate lead portion 132 and positioned.

  In the electrode laminate 120, the separator 140 is made of, for example, a nonwoven fabric made of a synthetic fiber that has been subjected to a hydrophilic treatment (see FIG. 4).

  Next, the positive electrode current collector plate 150 and the negative electrode current collector plate 250 of the power generation element 110 will be described with reference to FIGS. 6 and 7. Hereinafter, in FIG. 6, the upper right side is the base end side and the lower left side is the front end side of the positive electrode current collecting plate 150 and the negative electrode current collecting plate 250.

  The positive electrode current collector plate 150 joined to the positive electrode plate lead portions 132 of the many positive electrode plates 130 is formed by pressing a metal plate such as a Ni plate or a Ni-plated steel plate, and in order from the base end side, the positive electrode connecting portion 151, the positive electrode It has a plate-like base end portion 154, a positive electrode plate-like portion 152, and a positive electrode plate-like tip portion 155. As shown in FIGS. 6 and 7, the positive electrode collector plate 150 of the positive electrode current collector plate 150 is located on the base end side, and the positive electrode connection surface 151a that forms the center of the positive electrode connector 151 is rounded and dome-shaped. It is assumed to be a form. The positive electrode connecting portion 151 is a portion connected to a negative electrode connecting portion 251 of a negative electrode current collector plate 250 described later.

Of the positive electrode current collector plate 150, the positive electrode plate-like portion 152 includes five welded portions 153 including a proximal end side welded portion 153 </ b> H located on the most proximal side and a distal end side welded portion 153 </ b> L located on the most distal side. The reinforcing portions 157 are provided on both sides in the plate width direction (left-right direction in FIG. 7A). The positive electrode plate-like portion 152 is a flat plate having a size capable of contacting the positive electrode lead edge 132a of each positive electrode plate lead portion 132 of the positive electrode plates 130 included in the electrode laminate 120. Part 152a.
One welded portion 153 extends in a direction connecting both edges 152b of the positive electrode plate-like portion 152, and as described above, of the electrode stack 120, the large number of positive electrode plate lead portions 132 of the positive electrode plates 130 can be welded. (See FIG. 4).
In addition, as shown in FIGS. 6 and 7, the two edges 152 b in the plate width direction of the positive electrode plate-like portion 152 are bent from the positive electrode plate-like portion 152 and extend along the thickness direction of the positive electrode plate-like portion 152. Reinforcing portions 157 and 157 made of are provided. The reinforcing portions 157 and 157 are arranged so that the reinforcing portions 157 and 157 exist in the plate width direction of each welded portion 153. By providing the reinforcing portions 157 and 157 in the positive electrode plate-like portion 152, the positive electrode current collector plate 150 bends in the thickness direction at and near the welded portion 153 (base end side welded portion 153H, distal end side welded portion 153L). Is suppressed.

  The positive electrode plate-shaped base end portion 154 located between the base end side welded portion 153H and the positive electrode connecting portion 151 is formed with a base end side bent portion 156H used as a positioning portion (current collecting side positioning portion). . On the other hand, in the positive electrode current collector plate 150, a positive electrode plate-shaped front end portion 155 located on the front end side with respect to the front end side welded portion 153L is formed with a front end side bent portion 156L which is a current collecting side positioning portion.

  Further, the proximal-side bent portion 156H and the distal-end-side bent portion 156L are located along the periphery of the positive electrode plate lead portion 132 with the positive electrode plate lead portion 132 of the positive electrode current plate 130 of the positive electrode current collector plate 150. This is a positioning portion for positioning in the positioning direction along the positive electrode plate-like portion 152 of the current collector plate 150. Specifically, the proximal-side bent portion 156H and the distal-end-side bent portion 156L extend from the peripheral edge of the positive electrode plate electrode portion 131 in the positive electrode plate lead portion 132 of the positive electrode plate 130, and are integrated therewith. It is a current collecting side positioning portion that can be engaged with the positive electrode lead base end portion 132b and the positive electrode lead distal end portion 132c of the positive electrode plate lead portion 132, respectively. The proximal-side bent portion 156H and the distal-end-side bent portion 156L are respectively a part of the positive electrode plate-like base end portion 154 and a part of the positive electrode plate-like distal end portion 155 of the positive electrode current collector plate 150. Is bent in the thickness direction. Note that the proximal end side bent portion 156H and the distal end side bent portion 156L correspond to the bent portion of the present invention.

  Specifically, the base end side bent portion 156H is raised by making a U-shaped cut into a part of the positive electrode plate base end portion 154 and bending it in the plate thickness direction, and the base end side end surface 156Ht is the front end side (see FIG. 7 is downwardly curved). The base end side end surface 156Ht is a surface that engages with the positive electrode lead base end portion 132b of the positive electrode plate lead portion 132 of the positive electrode plate 130. The base-side bent portion 156H has a dimension (lamination) of the electrode laminate 120 when the dimension in the plate width direction (left-right direction in FIG. 7A) is seen in the thickness direction of the positive electrode plate 130. It becomes smaller than (height).

  Further, similarly to the base end side bend portion 156H, the front end side bend portion 156L is raised by inserting a U-shaped cut into a part of the positive electrode plate end portion 155 and bending it in the plate thickness direction, and the front end side end surface 156Lt. Is curved to face the base end side (upward in FIG. 7). This front end side end surface 156Lt is a surface that engages with the positive electrode lead front end portion 132 c of the positive electrode plate lead portion 132 of the positive electrode plate 130. Note that the tip-side bent portion 156L has a dimension (stacking height) when the dimension in the plate width direction (left and right direction in FIG. 7A) is seen in the plate thickness direction of the positive electrode plate 130. A) smaller.

Further, the base end side end surface 156Ht of the base end side bent portion 156H is seen in the plate width direction of the flat plate portion 152a (the left-right direction in FIG. 7B), and the tip end side (FIG. 7) becomes closer to the flat plate portion 152a. It is a surface inclined with respect to the flat plate portion 152a so that (b), (lower). On the contrary, the distal end side end surface 156Lt of the distal end side bent portion 156L is closer to the proximal end as it approaches the flat plate portion 152a when viewed in the plate width direction of the flat plate portion 152a (left and right direction in FIG. 7B). The surface is inclined with respect to the flat plate portion 152a so as to be (upward in FIG. 7B).
In this way, when the positive electrode plate lead portion 132 of the positive electrode plate 130 is abutted against the positive electrode current collector plate 150, the positive electrode plate lead portion 132 is easily guided by the proximal end surface 156 Ht and the distal end surface 156 Lt.

  In addition, the proximal-side bent portion 156H and the distal-end-side bent portion 156L are formed by bending a part of the positive electrode current collecting plate 150 in the plate thickness direction, so that the positioning portion (current collecting side positioning portion) is inexpensive. Can be easily formed.

Moreover, in this embodiment, the dimension of the board width direction (left-right direction in FIG. 7A) of the base end side bent portion 156H out of the base end side bent portion 156H and the tip end side bent portion 156L, It is smaller than the leading end side bent portion 156L and is about 1/3 of the entire width.
Thereby, the influence on the electric current which flows between the positive electrode connection part 151 of the positive electrode current collecting plate 150 and the positive electrode plate-shaped part 152 by having provided the base end side bending part 156H can be suppressed.

On the other hand, the negative electrode current collector plate 250 joined to a large number of negative electrode plates 230 differs from the positive electrode current collector plate 150 only in the polarity of conduction, and is substantially the same material and shape as the positive electrode current collector plate 150. It is an electric board. The negative electrode current collector plate 250 includes a negative electrode connecting portion 251, a negative electrode plate-like base end portion 254, a negative electrode plate-like portion 252, and a negative electrode plate-like tip portion 255 in order from the base end side. As shown in FIGS. 6 and 7, the negative electrode collector 251 of the negative electrode current collector plate 250 is positioned on the base end side, and the negative electrode connection surface 251 a that forms the center of the negative electrode connector 251 swells in a round dome shape. It is assumed to be a form. The negative electrode connecting portion 251 is a portion connected to the positive electrode connecting portion 151 of the positive electrode current collector plate 150.

Of the negative electrode current collector plate 250, the negative electrode plate-like portion 252 includes five welded portions 253 including a proximal end side welded portion 253H located on the most proximal side and a distal end side welded portion 253L located on the most distal end side. The reinforcing portions 257 are provided on both sides in the plate width direction (left-right direction in FIG. 7A). The negative electrode plate portion 252 is a flat plate portion 252 a having a size capable of contacting the negative electrode lead edge 232 a of each negative electrode plate lead portion 232 of each negative electrode plate 230 included in the electrode laminate 120. Is included.
One welded portion 253 extends in a direction connecting both edges 252b of the negative electrode plate-like portion 252, and as described above, the electrode plate 120 can be welded with a large number of negative electrode plate lead portions 232 of the negative electrode plate 230. (See FIG. 4).
Further, as shown in FIGS. 6 and 7, the two edges 252 b of the negative electrode plate portion 252 in the plate width direction are bent from the negative electrode plate portion 252 and extend along the thickness direction of the negative electrode plate portion 252. Reinforcing portions 257 and 257 made of are provided. The reinforcing portions 257 and 257 are arranged such that the reinforcing portions 257 and 257 exist in the plate width direction of each welded portion 253. By providing the reinforcing portions 257 and 257 in the negative electrode plate-like portion 252, the negative electrode current collector plate 250 bends in the thickness direction at and near the welded portion 253 (base end side welded portion 253H, distal end side welded portion 253L). Is suppressed.

  A negative plate-like base end portion 254 located between the base end side welding portion 253H and the negative electrode connecting portion 251 is formed with a base end side bent portion 256H used as a positioning portion (current collecting side positioning portion). . On the other hand, in the negative electrode current collector plate 250, a negative electrode plate-shaped front end portion 255 positioned on the front end side from the front end side welded portion 253L is formed with a front end side bent portion 256L that is a current collector side positioning portion.

  Further, the base end side bent portion 256H and the distal end side bent portion 256L are arranged along the periphery of the negative electrode plate lead portion 232 of the negative electrode current collector plate 250 with the negative electrode plate lead portion 232 of the negative electrode plate 230, and This is a positioning portion for positioning in the positioning direction along the negative electrode plate-like portion 252 of the current collector plate 250. Specifically, the proximal-side bent portion 256H and the distal-end-side bent portion 256L extend from the periphery of the negative electrode plate electrode portion 231 in the negative electrode plate lead portion 232 of the negative electrode plate 230, and are integrated therewith. It is a current collecting side positioning portion that can engage with the negative electrode lead base end portion 232b and the negative electrode lead distal end portion 232c of the negative electrode plate lead portion 232, respectively. The proximal-side bent portion 256H and the distal-end-side bent portion 256L are part of the negative electrode plate-like base end portion 254 and part of the negative electrode plate-like distal end portion 255 of the negative electrode current collector plate 250, respectively. Is bent in the thickness direction.

  Specifically, the base end side bent portion 256H is raised by making a U-shaped cut into a part of the negative electrode plate base end portion 254 and bending it in the plate thickness direction, and the base end side end surface 256Ht is the front end side (see FIG. 7 is downwardly curved). The base end side end surface 256Ht is a surface that engages with the negative electrode lead base end portion 232b of the negative electrode plate lead portion 232 of the negative electrode plate 230. The base-side bent portion 256H has a dimension (lamination) of the electrode laminate 120 when the dimension in the plate width direction (left-right direction in FIG. 7A) is seen in the thickness direction of the negative electrode plate 230. It becomes smaller than (height).

  Similarly to the base end side bend portion 256H, the front end bend portion 256L is also raised by inserting a U-shaped cut into a part of the negative electrode plate end portion 255 and bending it in the plate thickness direction. Is curved to face the base end side (upward in FIG. 7). The distal end side end surface 257Lt is a surface that engages with the negative electrode lead distal end portion 232c of the negative electrode plate lead portion 232 of the negative electrode plate 230. Note that the leading end side bent portion 256L has a dimension (stacking height) when the dimension in the plate width direction (left and right direction in FIG. 7A) is seen in the plate thickness direction of the negative electrode plate 230. A) smaller.

Further, the base end side end surface 256Ht of the base end side bent portion 256H is seen in the plate width direction of the flat plate portion 252a (the left-right direction in FIG. 7B), and the tip end side (FIG. 7) becomes closer to the flat plate portion 252a. It is a surface inclined with respect to the flat plate portion 252a so that (b), (lower). On the contrary, the distal end side end surface 256Lt of the distal end side bent portion 256L is closer to the proximal end as it approaches the flat plate portion 252a when viewed in the plate width direction of the flat plate portion 252a (left and right direction in FIG. 7B). The surface is inclined with respect to the flat plate portion 252a so as to be (upward in FIG. 7B).
In this way, when the negative electrode plate lead portion 232 of the negative electrode plate 230 is abutted against the negative electrode current collector plate 250, the negative electrode plate lead portion 232 can be easily guided by the proximal end surface 256Ht and the distal end surface 256Lt.

  In addition, since the base end side bend portion 256H and the tip end bend portion 256L are formed by bending a part of the negative electrode current collector plate 250 in the plate thickness direction, the positioning portion (current collection side positioning portion) is inexpensive. Can be easily formed.

Moreover, in this embodiment, the dimension of the board width direction (left-right direction in Fig.7 (a)) of the base end side bending part 256H among the base end side bending part 256H and the front end side bending part 256L is as follows. The size is smaller than the distal end side bent portion 256L, and is about 1/3 of the entire width.
Thereby, the influence on the electric current which flows between the negative electrode connection part 251 and the negative electrode plate-shaped part 252 of the negative electrode current collecting plate 250 by having provided the base end side bending part 256H can be suppressed.

In the present embodiment, the positive electrode current collector plate 150 is joined to the positive electrode plate lead portion 132 of each positive electrode plate 130 at five welding sites 153 per positive electrode plate 130. The positive electrode current collector plate 150 is subjected to electron beam welding at five welding sites 153 in a state where the flat plate portion 152 a is abutted against the positive electrode lead edge 132 a of the positive electrode plate lead portion 132 of each positive electrode plate 130. Each positive electrode plate lead part 132 is joined.
On the other hand, similarly to the positive electrode current collector plate 150, the negative electrode current collector plate 250 is joined to the negative electrode plate lead portion 232 of each negative electrode plate 230 at five welding sites 253 per one negative electrode plate 230. The negative electrode current collector plate 250 is subjected to electron beam welding at five welding sites 253 in a state where the flat plate portion 252a is abutted against the negative electrode lead edge 232a of the negative electrode plate lead portion 232 of each negative electrode plate 230. Each negative plate lead portion 232 is joined.

Next, the battery case 180 in the secondary battery 100 will be described with reference to FIG.
As described above, the battery case 180 includes the case main body member 181 and the lid member 186. The case main body member 181 is formed in a rectangular parallelepiped shape by integral molding of resin, the insertion side (upper side in FIG. 1) has an opening 185, and six accommodating portions divided by five partition walls 182 therein. 183 (see FIGS. 1 and 2). Each of these accommodating portions 183 has a size capable of accommodating the power generation element 110 (see FIG. 2). As shown in FIG. 2, the case main body member 181 is provided with a connecting hole 184 that communicates with the accommodating portions 183 and 183 adjacent to each other on the insertion side (upward in FIG. 2) of each partition wall 182. The connection hole 184 has a diameter into which the positive electrode connection portion 151 of the positive electrode current collector plate 150 and the negative electrode connection portion 251 of the negative electrode current collector plate 250 can be inserted.

The lid member 186 that closes the opening of the case body member 181 is made of resin and has a substantially rectangular plate shape. The lid member 186 is provided with a safety valve 191, a temperature sensor mounting hole 192, and a liquid injection port 187. The safety valve 191 operates when the internal pressure of the battery case 180 exceeds a predetermined value, discharges internal gas (hydrogen gas or the like) to the outside, and suppresses an increase in internal pressure. A temperature sensor (not shown) can be inserted into the temperature sensor mounting hole 192 so that the temperature of the battery can be detected. The liquid injection port 187 is a part for injecting an electrolytic solution (not shown) into the housing portion 183 and is liquid-tightly closed with a liquid injection lid 193 after the electrolytic solution is injected. In addition, as electrolyte solution, the alkaline aqueous solution of 1.2-1.4 specific gravity containing KOH can be used, for example.

Next, the manufacturing method of the secondary battery 100 of this embodiment, in particular, the joining of the positive electrode current collector plate 150 and the negative electrode current collector plate 250 and the electrode laminate 120 will be described.
First, when forming the electrode laminate 120, the manufactured positive electrode plate 130 and negative electrode plate 230 are sufficiently dried, and then the positive electrode plate 130 is inserted into the separator 140. In the electrode stack 120, as described above, the positive plates 130 and the negative plates 230 inserted in the separator 140 are alternately stacked.

  Specifically, in the step of alternately laminating the positive electrode plates 130 and the negative electrode plates 230 to form the electrode laminate 120, the positive electrode plates 130 and the negative electrode plates 230 are positioned using a lamination jig (not shown). Laminate. This stacking jig is arranged corresponding to the arrangement of jig insertion holes 134 (134A to 134D) and jig insertion holes 234 (234A to 234D) drilled in the positive electrode plate lead part 132 and the negative electrode plate lead part 232. In addition, a pin having a diameter slightly smaller than these hole diameters is provided.

  In this electrode laminate 120, the positive electrode plate 130 inserted into the separator 140 with the positive electrode plate lead portion 132 of each positive electrode plate 130 and the negative electrode plate lead portion 232 of each negative electrode plate 230 positioned, and Negative electrode plates 230 are alternately stacked (see FIG. 5). It should be noted that the electrode laminate 120 at this stage is merely obtained by aligning and laminating the positive electrode plate 130, the negative electrode plate 230, and the separator 140 with a lamination jig (not shown).

Next, the positive electrode current collector plate 150 and each positive electrode plate 130 of the electrode laminate 120 are joined. The positive electrode current collector plate 150 and each positive electrode plate 130 are joined through a positive electrode side positioning step and a positive electrode side welding step.
First, in the positive electrode side positioning step, among the positive electrode plates 130 included in the stacked electrode laminate 120, the long side direction between the positive electrode plate lead portion 132 (see the front side in FIG. 5) and the positive electrode current collector plate 150 ( In FIG. 1 and FIG. 2, the vertical direction) is positioned by the proximal end side bent portion 156H and the distal end side bent portion 156L.

In the positive electrode side positioning step, the welding part 153 of the positive electrode current collector plate 150 is attached to the positive electrode lead edge 132a of the positive electrode plate lead part 132 of each positive electrode plate 130 included in the electrode laminate 120 laminated by the lamination jig. Strike. At this time, the base end side end surface 156Ht of the base end side bent portion 156H of the positive electrode current collector plate 150 engages with the positive electrode plate lead base end portion 132a of the positive plate lead portion 132, and the front end side bent portion 156L. The positive electrode current collector plate 150 is abutted against each positive electrode plate lead portion 132 so that the front end side end surface 156Lt of the positive electrode plate lead portion 132 is engaged with the positive electrode plate lead tip portion 132c. Thereby, the positive electrode current collector plate 150 is laminated in the long side direction (vertical direction in FIGS. 1 and 2) by the base end side bent portion 156H and the distal end side bent portion 156L. Positioned with respect to 120 positive plates 130.
In addition, since the board width direction dimension of the base end side bending part 156H and the front end side bending part 156L is made smaller than the dimension of the lamination direction of the electrode laminated body 120, it is an electrode laminated body to engage with these 120, which is a part of the positive electrode plate 130 included in the electrode 120, and is positioned with the positive electrode current collector plate 150 in a state where the positive electrode plates 130 are stacked by the stacking jig. As long as positioning with respect to the positive electrode current collector plate 150 can be performed using any of the above, positioning can be performed in the same manner as any positive electrode plate 130.

Next, in the negative electrode side positioning step, the welded portion of the negative electrode current collector plate 250 is welded to the negative electrode lead edge 232a of the negative electrode plate lead part 232 of each negative electrode plate 230 included in the electrode laminate 120 laminated by the lamination jig. Hit 253. At this time, in the negative electrode current collector plate 250, the base end side end face 256 </ b> Ht of the base end side bent portion 256 </ b> H is the negative electrode plate lead base end portion 232 a of the negative electrode plate lead portion 232.
And the negative electrode current collector plate 250 to each negative electrode plate lead portion 232 so that the front end side end surface 256Lt of the front end side bent portion 256L is engaged with the negative electrode plate lead front end portion 232c of the negative electrode plate lead portion 232. Strike. As a result, the negative electrode current collector plate 250 is laminated in the long side direction (vertical direction in FIGS. 1 and 2) by the base end side bend portion 256H and the tip end bend portion 256L. Positioned with respect to 220 negative electrode plate 230.
In addition, since the board width direction dimension of the base end side bending part 256H and the front end side bending part 256L is made smaller than the dimension of the lamination direction of the electrode laminated body 120, it is an electrode laminated body that engages with these. 120, which is a part of the negative electrode plate 230, is positioned with the negative electrode current collector plate 250 in a state where the negative electrode plates 230 are stacked by the stacking jig. As long as positioning with respect to the negative electrode current collector plate 250 can be performed using any of these, positioning can be performed with any negative electrode plate 230 in the same manner.

  Next, an alternating magnetic field is applied to each of the positive electrode current collector plate 150 and the negative electrode current collector plate 250 to demagnetize. This is because before the welding, the magnetism applied to the positive electrode current collector plate 150 and the negative electrode current collector plate 250 is removed to prevent the magnetism from adversely affecting the electron beam.

  Next, in the positive electrode side welding step, the welded portion 153 of the positive electrode current collector plate 150 is welded to the positive electrode plate lead portion 132 of each positive electrode plate 130 in the state of being positioned in the positive electrode side positioning step described above. Specifically, in the welding between the positive electrode current collector plate 150 and each positive electrode plate 130, the positive electrode lead of the positive electrode plate lead portion 132 having the welded portion 153 of the positive electrode current collector plate 150 in each positive electrode plate 130 in a vacuum. An electron beam is irradiated from the back side (left side in FIG. 7B) to the welded portion 153 of the positive electrode current collector plate 150 while being in contact with the edge 132a. Thereby, the positive electrode current collecting plate 150 and each positive electrode plate 130 are melted and joined to each other at the five welded portions 153.

  On the other hand, in the negative electrode side welding step, the welded portion 253 of the negative electrode current collector plate 250 is welded to the negative electrode plate lead portion 232 of each negative electrode plate 230 in the state of being positioned in the negative electrode side positioning step described above. Specifically, in the welding between the negative electrode current collector plate 250 and each negative electrode plate 230, the negative electrode lead of the negative electrode plate lead portion 232 having the welded portion 253 of the negative electrode current collector plate 250 in each negative electrode plate 230 in vacuum. The electron beam is irradiated from the back side (left side in FIG. 7B) to the welded portion 253 of the negative electrode current collector plate 250 while being in contact with the edge 232a. As a result, the negative electrode current collector plate 250 and each negative electrode plate 230 are melted and joined to each other at the five welded portions 253.

  Thus, the power generation element 110 is formed as a unit cell including the positive electrode current collector plate 150 on one side and the negative electrode current collector plate 250 on the other side. When the power generation element 110 in this state is housed in the housing portion 183, the positive electrode connecting portion 151 of the positive electrode current collector plate 150 and the negative electrode connecting portion 254 of the negative electrode current collector plate 250 are adjacent to each partition wall 182 of the case body member 181. It is designed not to interfere.

  Further, as shown in FIGS. 1 and 2, the positive electrode current collector plate 150 is arranged on the left side and the negative electrode current collector plate 250 is arranged on the right side, and the six power generation elements 110 are respectively connected from the openings 185 of the case main body member 181. It accommodates in each accommodating part 183. Next, for the power generation elements 110 and 110 adjacent to each other, the negative electrode current collector plate 250 of the power generation element 110 housed in the housing section 183 on one side and the power generation element 110 housed in the housing section 183 on the other side. The positive electrode current collector plate 150 is connected.

Specifically, in FIG. 2, the negative electrode connecting portion 251 of the negative electrode current collector plate 250L (250) included in the power generation element 110L (110) on one side (left side in the figure), and the other side (right side in the figure). The positive electrode connecting portion 151 of the positive electrode current collector plate 150R (150) of the power generation element 110R is inserted into the communication hole 185 formed in the partition wall 183 of the case main body member 181. In this communication hole 185, the negative electrode connecting surface 251a of the inserted negative electrode connecting portion 251 and the positive electrode connecting surface 151a of the positive electrode connecting portion 151 are in contact with each other, and the positive electrode connecting portion 151 and the negative electrode connecting portion 251 are resistance-welded. (See FIG. 2). As a result, the adjacent power generation elements 110L and 110R are connected in series (see FIG. 2). Thus, the six power generation elements 110 (unit cells) are connected in series.

  Next, the opening 185 of the case main body member 181 in which the six power generation elements 110 are arranged in the respective accommodating portions 183 is liquid-tightly closed with the lid member 186. Then, a predetermined amount of electrolyte is injected into each housing portion 183 from the liquid injection port 187, and the liquid injection port 187 is closed with a liquid injection lid 193. In this way, the secondary battery 100 shown in FIG. 1 can be obtained.

  In the manufacturing method of the secondary battery 100 of the present embodiment, the positive electrode current collector plate 150 is provided with a proximal end side bent portion 156H and a distal end side bent portion 156L which are positioning portions (current collecting side positioning portions), and these are provided. Since the positive electrode plate lead portion 132 of the positive electrode plate 130 is engaged, when the welded portion 153 of the positive electrode current collector plate 150 is welded to the positive electrode plate lead portion 132 of the positive electrode plate 130, It is possible to prevent misalignment (in the vertical direction in FIGS. 1 and 2) and weld to an appropriate position.

Further, two of the base end side bent portion 156H and the tip end side bent portion 156L are formed on the positive electrode current collector plate 150, and in the positioning step, of these and the positive electrode plate lead portion 132 of the positive electrode plate 130, the positive electrode lead The base end portion 132b and the positive electrode lead distal end portion 132c were engaged with each other to perform positioning in the long side direction (vertical direction in FIGS. 1 and 2).
By doing in this way, it is not necessary to provide the structure part (for example, recessed part and convex part) for positioning in the positive electrode plate lead part 132 of each positive electrode plate 130. FIG. For this reason, in the positive electrode plate 130, the structure and form of the positive electrode plate lead portion 132 are simplified, and the positive electrode plate lead portion 132 is easily provided on the positive electrode plate 130. However, the positioning portion can be provided also on the positive electrode plate or only on the positive electrode plate.
The same applies to the welding of the negative electrode current collector plate 250 and the negative electrode plate 230.

In the above, the present invention has been described with reference to the embodiments. However, the present invention is not limited to the above embodiments, and it is needless to say that the present invention can be appropriately modified and applied without departing from the gist thereof.
For example, in the present embodiment, the first current collector plate is a positive electrode current collector plate 150 and the second current collector plate is a negative electrode current collector plate 250. However, the first current collector plate may be the negative electrode side and the second current collector plate may be the positive electrode side.
Moreover, in the secondary battery 100 of this embodiment, all the adjacent electric power generation elements 110 were connected in series. However, the battery may be configured by connecting all or some of the power generation elements in parallel.

  In the present embodiment, the welded portion 153 between the positive electrode current collector plate 150 and the positive electrode plate 130 and the welded portion 253 between the negative electrode current collector plate 250 and the negative electrode plate 230 are combined into one positive electrode plate 130 and negative electrode plate 230. There were 5 places each. However, in both bipolar electrode plates, the number of welded portions of one electrode plate with the first current collector plate and the second current collector plate can be appropriately changed.

It is a figure which shows the form of the secondary battery which concerns on embodiment, (a) is a top view, (b) is the front view which showed a part by arrow AA sectional drawing of (a). It is an enlarged view of the principal part in FIG. 1, and is explanatory drawing for demonstrating the connection of electric power generation elements. It is a perspective view which shows the electric power generation element which comprises the secondary battery which concerns on embodiment. It is arrow BB sectional drawing of FIG. It is the perspective view which abbreviate | omitted and illustrated the electrode laminated body used for the electric power generation element which concerns on embodiment. It is a perspective view which shows the positive electrode current collecting plate and negative electrode current collecting plate which were used for the electric power generation element which concerns on embodiment. It is a figure which shows the positive electrode current collecting plate and negative electrode current collecting plate of FIG. 6, (a) is a top view, (b) is a side view.

100 Secondary battery (battery)
DESCRIPTION OF SYMBOLS 110 Power generation element 120 Electrode laminated body 130 Positive electrode plate (1st electrode plate)
131 Positive electrode plate electrode part (electrode part)
132 Positive plate lead part (first current collecting lead part)
230 Negative electrode plate (second electrode plate)
140 Separator 150, 150R Positive current collector (first current collector)
153 Welded part 156H Base end side bent portion (positioning portion, current collecting side positioning portion, bent portion)
156L Front end side bent portion (positioning portion, current collecting side positioning portion, bent portion)

Claims (4)

An electrode laminate in which first electrode plates and second electrode plates are alternately laminated via separators,
The first electrode plate extends from a rectangular flat plate-shaped electrode portion that holds an active material and a peripheral edge of one long side of the electrode portion, and is integrated with the electrode portion, and is generated in the electrode portion. An electrode laminate including a first current collecting lead part having a rectangular plate shape for collecting electric charge;
In each of the first electrode plate, only in the first current collector lead section of that, and the production of batteries having a power generating element having a first collector plate formed by welding one or a plurality of welded section A method,
Among the plurality of first electrode plates included in the electrode laminate, at least one of the first current collecting lead portion and the first current collecting plate of at least one of the first electrode plates is:
A positioning portion that engages the first current collecting plate and the first current collecting lead portion of the first electrode plate to perform positioning in a positioning direction along the long side of the first current collecting lead portion. Have
The positioning part is
A convex lead-side positioning portion provided on the first current collecting lead portion of the first electrode plate;
A convex current collecting side positioning portion provided on the first current collecting plate;
A convex current collecting side positioning portion provided on the first current collecting plate and a concave lead side positioning portion that can be engaged with the convex current collecting side positioning portion, or
A concave current collecting side positioning portion provided on the first current collecting plate and a convex lead side positioning portion that can be fitted and engaged therewith,
A positioning step of positioning the electrode laminate and the first current collector by the positioning unit;
A welding step of welding the first current collector plate to the first current collector lead portion of each of the first electrode plates at the welding site in a state of being positioned in the positioning step. . A battery manufacturing method according to claim 1, comprising:
The first current collector plate is
The positioning part,
Among the first current collecting lead portions of the first electrode plate, there are two convex current collecting side positioning portions that can be engaged with both end portions in the positioning direction, respectively.
In the positioning step, at least one of the first electrode plates, the both ends of the first current collecting lead portion of the first electrode plate, and the two current collectors of the first current collector plate. A battery manufacturing method for positioning the first current collecting lead portion of the first electrode plate and the first current collecting plate by engaging side positioning portions respectively. A method for producing a battery according to claim 1 or claim 2,
The positioning part or the current collecting side positioning part is
A method of manufacturing a battery, which is a bent portion formed by bending a part of the first current collector plate in the plate thickness direction. A method of manufacturing a battery according to claim 3,
The bent portion of the first current collector plate is
A battery manufacturing method wherein the first current collector plate is welded to the first electrode plate, and when viewed in the thickness direction of the first electrode plate, the size of the electrode laminate is smaller.

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