JP2015204248A - Electric insulation sheet for square battery, square battery and manufacturing method of square battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric insulation sheet for a square battery capable of easily preventing a positive electrode and a negative electrode from being electrically short-circuited via an outer can, and the square battery employing the electric insulation sheet.SOLUTION: In a square battery, an electric insulation sheet 8 is disposed between an electrode group and a sealing plate and includes a main plate part 80, a pair of first plate parts 81 and a pair of second folded parts 82. The main plate part 80 includes an outer edge including a pair of first sides 80a extending substantially in parallel and a window 86 through which an electrode tab is passed. Within the square battery, the main plate part 80 is opposite to an end face of the electrode group in the state where the electrode tab is passed through the window 86, and is disposed in such a manner that the first sides 80a are along an inner surface of the outer can. The pair of first plate parts 81 are provided continuously to the pair of first sides 80a of the main plate part 80, respectively. The pair of folded parts 82 are provided along the pair of first sides 80a of the main plate part 80, respectively, and enable the first plate parts 81 to rise relatively to the main plate part 80.

Description

  The present invention relates to a prismatic battery, a method for producing the same, and an electrical insulating sheet used for them.

  FIG. 13 is a longitudinal sectional view conceptually showing an example of a conventional prismatic battery. As shown in FIG. 13, the conventional prismatic battery seals a plurality of electrode groups 101, a bottomed cylindrical outer can 102 in which these electrode groups 101 are accommodated, and an opening 102 a of the outer can 102. The sealing plate 103 includes a positive external terminal 104 and a negative external terminal (not shown) provided on the sealing plate 103 (see, for example, Patent Document 1). Although not shown, in each of the electrode groups 101, a plurality of positive plates and a plurality of negative plates are alternately stacked via separators. Further, each positive electrode plate has a positive electrode tab protruding from an edge facing the opening 102a of the outer can 102, and each negative electrode plate has a negative electrode tab protruding from the edge facing the opening 102a of the outer can 102. doing. In each of the electrode groups 101, a plurality of positive electrode tabs belonging to the electrode group 101 overlap to form one bundle, and a plurality of negative electrode tabs belonging to the electrode group 101 overlap to form one bundle. Negative electrode terminal portion (not shown).

  In the conventional square battery, the end portion of the positive electrode lead plate 106 is welded to each positive electrode terminal portion 105. The plurality of positive electrode lead plates 106 respectively provided on the positive electrode terminal portion 105 are bundled together, and the tip of the bundle of the positive electrode lead plates 106 is welded or screwed to the positive electrode external terminal 104. Further, the bundle of positive electrode lead plates 106 is folded in a space in the outer can 102 provided between the electrode group 101 and the sealing plate 103. In this way, each of the positive electrode terminal portions 105 is electrically connected to the positive electrode external terminal 104 via the positive electrode lead plate 106. Similarly, each of the negative electrode terminal portions is electrically connected to the negative electrode external terminal via a negative electrode lead plate.

JP 2011-165475 A JP 2004-152581 A

  However, in the conventional prismatic battery, when the positive electrode tab and the negative electrode tab are deformed by an external force generated by vibration or collision, these tabs and the lead plate come into contact with the outer can 102, and as a result, the positive electrode, the negative electrode, However, there is a risk of electrical short circuit through the outer can 102.

  Thus, an electrically insulating frame that prevents such a short circuit has been proposed (see, for example, Patent Document 2). Specifically, this frame has a bottom plate portion having a window through which a positive electrode tab or the like is passed, and a frame-like side wall portion fixed perpendicularly to the outer edge of the bottom plate portion. According to this frame body, even when the positive electrode tab and the negative electrode tab are deformed by an external force generated by vibration or collision, the contact between the tab and the lead plate and the outer can 102 is prevented by the side wall portion of the frame body. . However, the proposed frame body is one in which the bottom plate portion and the side wall portion are integrally formed by a mold or the like, and its manufacture is complicated.

  In addition, in order to improve the volume energy of the rectangular battery, a technique for shortening the length of the lead plate and a technique using another connecting member instead of the lead plate have been proposed. However, if the conventional frame is used for the prismatic battery manufactured by these techniques, when the electrode group 101 and the external terminal are connected by processing such as welding in the manufacturing process, the processing is not performed. , It is obstructed by the frame (mainly its side wall).

  Accordingly, an object of the present invention is to use an electrical insulating sheet for a square battery that can easily realize prevention of an electrical short circuit between a positive electrode and a negative electrode via an outer can, and the electrical insulating sheet. And a manufacturing method thereof.

  One aspect of the present invention relates to an electrical insulating sheet for a prismatic battery. The prismatic battery in which this electrical insulating sheet is used has an electrode group in which a plurality of first electrode plates and a plurality of second electrode plates are stacked with a separator interposed therebetween, and a bottomed cylindrical exterior that accommodates the electrode groups A can, a sealing plate for sealing the opening of the outer can, and an external terminal provided on the sealing plate, each of which is provided on the plurality of first electrode plates from the end face of the electrode group facing the opening of the outer can. The plurality of electrode tabs protrude, and the external terminals and the electrode tabs are electrically connected to each other. And an electrical insulation sheet is arrange | positioned between an electrode group and a sealing board in this square battery. Specifically, the electrical insulating sheet has a main flat plate portion, a pair of first flat plate portions, and a pair of first bent portions. Here, the main flat plate portion has an outer edge including a pair of first sides extending substantially in parallel and a window through which the electrode tab is passed, and the electrode tab is passed through the window in the rectangular battery. Opposite to the end surface of the electrode group, the first side is disposed along the inner surface of the outer can. The pair of first flat plate portions are connected to the pair of first sides of the main flat plate portion, respectively. The pair of first bent portions is provided along the pair of first sides of the main flat plate portion, respectively, and allows the first flat plate portion to rise with respect to the main flat plate portion.

  Another aspect of the present invention relates to a prismatic battery. The prismatic battery includes an electrode group in which a plurality of first electrode plates and a plurality of second electrode plates are stacked via a separator, a bottomed cylindrical outer can in which the electrode group is accommodated, and an outer can The sealing board which sealed the opening, the external terminal provided in the sealing board, and the electrical insulation sheet arrange | positioned between an electrode group and a sealing board are provided. Here, a plurality of electrode tabs respectively provided on the plurality of first electrode plates protrude from the end face of the electrode group facing the opening of the outer can, and the external terminals and the electrode tabs are electrically connected to each other. . The electrical insulating sheet has a main flat plate portion, a pair of first flat plate portions, and a pair of first bent portions. The main flat plate portion has an outer edge including a pair of first sides extending substantially in parallel and a window through which an electrode tab is passed, facing the end surface of the electrode group, and the first side being an inner surface of the outer can. It is arranged along. The pair of first flat plate portions are connected to the pair of first sides of the main flat plate portion, respectively. The pair of first bent portions are provided between the main flat plate portion and the first flat plate portion along the pair of first sides of the main flat plate portion, respectively, and the first flat plate portion is predetermined with respect to the main flat plate portion. It is bent to form an angle.

  Still another aspect of the present invention relates to a method for manufacturing the prismatic battery. This manufacturing method includes steps (i) to (iii). Step (i) is a step of arranging the electrical insulating sheet with respect to the electrode group in a state before the first bent portion is bent, and in step (i), a window formed in the main flat plate portion. Pass the electrode tab through. After step (i), in step (ii), the electrode tab is welded to the external terminal provided on the sealing plate while maintaining the electrical insulating sheet in the state before being bent. After step (ii), in step (iii), the electrode group is housed in an outer can and the opening of the outer can is sealed with a sealing plate. In step (iii), when the electrode group is accommodated in the outer can, the first flat plate portion is raised with respect to the main flat plate portion by bending the first bent portion of the electrical insulating sheet.

  According to the above aspect of the present invention, in the square battery, it is easily realized to prevent an electrical short circuit between the positive electrode and the negative electrode via the outer can.

It is the perspective view which showed notionally the square battery which concerns on embodiment of this invention. It is a disassembled perspective view of a square battery. It is the side view which showed the internal structure of the square battery seeing from the 1st side wall of the armored can with which a square battery is provided. It is the side view which showed the internal structure of the square battery seeing from the 2nd side wall of the exterior can with which a square battery is equipped. It is the longitudinal cross-sectional view which showed notionally the structure of (a) positive electrode and (b) negative electrode which each of the some electrode group with which a square battery is equipped has. (A) The top view which showed the electrical insulation sheet with which a square battery is equipped, (b) The principal part enlarged view of the cross section along the VIb-VIb line | wire shown by Fig.6 (a). It is the perspective view which showed the state before (a) bending and (b) the state after bending of an electrically insulating sheet. It is a perspective view used for description of the 1st accommodation process. It is a perspective view used for description of the 2nd accommodation process. It is a perspective view used for description of the 2nd accommodation process. It is a perspective view used for description of a welding process. (A) The top view which showed the modification of the electrical insulation sheet, (b) It is the principal part enlarged view of the cross section along the XIIb-XIIb line | wire shown by Fig.12 (a). It is the longitudinal cross-sectional view which showed an example of the conventional square battery conceptually.

  The electrical insulation sheet for square batteries according to the embodiment of the present invention is used in the following square batteries. That is, the prismatic battery includes an electrode group in which a plurality of first electrode plates and a plurality of second electrode plates are stacked via a separator, a bottomed cylindrical outer can in which the electrode group is accommodated, A plurality of electrodes provided on each of the plurality of first electrode plates from an end face of the electrode group that includes a sealing plate that seals the opening of the can and an external terminal provided on the sealing plate and faces the opening of the outer can. The tab protrudes, and the external terminal and the electrode tab are electrically connected to each other. And an electrical insulation sheet is arrange | positioned between an electrode group and a sealing board in this square battery. Specifically, the electrical insulating sheet has a main flat plate portion, a pair of first flat plate portions, and a pair of first bent portions. Here, the main flat plate portion has an outer edge including a pair of first sides extending substantially in parallel and a window through which the electrode tab is passed, and the electrode tab is passed through the window in the rectangular battery. Opposite to the end surface of the electrode group, the first side is disposed along the inner surface of the outer can. The pair of first flat plate portions are connected to the pair of first sides of the main flat plate portion, respectively. The pair of first bent portions is provided along the pair of first sides of the main flat plate portion, respectively, and allows the first flat plate portion to rise with respect to the main flat plate portion.

  Note that the prismatic battery includes those with rounded corners and edges. The first electrode plate is a positive electrode plate, and the second electrode plate is a negative electrode plate. Alternatively, the first electrode plate is a negative electrode plate, and the second electrode plate is a positive electrode plate.

  The electrical insulating sheet can be produced by a simple method such as punching for a large-sized electrical insulating sheet. Further, in the process of manufacturing the rectangular battery, when the electrical insulation sheet is accommodated in the outer can, the electrical insulation sheet is disposed with respect to the electrode group so that the electrode tab passes through the window, and the first folding The first flat plate portion is raised with respect to the main flat plate portion by bending the bent portion. Thereby, in a square battery, a 1st flat plate part will be arrange | positioned along the inner surface of an armored can. As a result, the first flat plate portion is interposed between the electrode tab and the outer can. Therefore, in the manufactured rectangular battery, even when the electrode tab is deformed by an external force generated by vibration or collision, the contact between the electrode tab and the outer can is prevented by the first flat plate portion. Therefore, in the rectangular battery, an electrical short circuit between the positive electrode and the negative electrode via the outer can is prevented. And the said electrical insulation sheet makes it easy to implement | achieve prevention of such an electrical short circuit.

  The electrical insulating sheet for a square battery has a sheet surface including the surface of the main flat plate portion and a sheet back surface including the back surface of the main flat plate portion. In a preferred specific configuration, each of the first bent portions is A V-shaped groove formed on at least one of the sheet surface and the sheet back surface is provided along the first side of the main flat plate portion. More specifically, at least one through hole is formed in each of the V-shaped grooves. Thereby, bending of an electrical insulation sheet becomes easy. The V-shaped groove includes a groove having a rounded V-shaped tip and a U-shaped groove.

  In another preferable specific configuration of the electrical insulating sheet for a square battery, the outer edge of the main flat plate portion further includes a pair of second sides extending substantially perpendicular to the first side, and the electrical insulating sheet includes: In addition to the 1 flat plate portion and the first bent portion, the device further includes a pair of second flat plate portions and a pair of second bent portions. Here, the pair of second flat plate portions are connected to the pair of second sides of the main flat plate portion, respectively. The pair of second bent portions are respectively provided along the pair of second sides of the main flat plate portion, and allow the second flat plate portion to rise with respect to the main flat plate portion.

  According to this electrical insulating sheet, an electrical short circuit between the positive electrode and the negative electrode via the outer can can be more reliably prevented. Specifically, it is as follows. In the manufacturing process of the prismatic battery, when the electrical insulating sheet is accommodated in the outer can, the first flat plate portion and the main flat plate portion are bent by bending the second bent portion in addition to the first bent portion. Each second flat plate portion is raised. Thereby, in a square battery, a 1st flat plate part and a 2nd flat plate part are arrange | positioned along the inner surface of an armored can. As a result, the first flat plate portion and the second flat plate portion are interposed between the electrode tab and the outer can. Therefore, in the manufactured rectangular battery, even when the electrode tab is deformed by an external force generated by vibration or collision, the contact between the electrode tab and the outer can is prevented by the first flat plate portion and the second flat plate portion. Therefore, in the rectangular battery, an electrical short circuit between the positive electrode and the negative electrode via the outer can can be more reliably prevented.

  A prismatic battery according to an embodiment of the present invention is a prismatic battery manufactured using the electrical insulating sheet. Specifically, the prismatic battery includes an electrode group in which a plurality of first electrode plates and a plurality of second electrode plates are stacked via a separator, and a bottomed cylindrical outer can in which the electrode group is accommodated. And a sealing plate that seals the opening of the outer can, an external terminal provided on the sealing plate, and an electrical insulating sheet disposed between the electrode group and the sealing plate. Here, a plurality of electrode tabs respectively provided on the plurality of first electrode plates protrude from the end face of the electrode group facing the opening of the outer can, and the external terminals and the electrode tabs are electrically connected to each other. . The electrical insulating sheet has a main flat plate portion, a pair of first flat plate portions, and a pair of first bent portions. The main flat plate portion has an outer edge including a pair of first sides extending substantially in parallel and a window through which an electrode tab is passed, facing the end surface of the electrode group, and the first side being an inner surface of the outer can. It is arranged along. The pair of first flat plate portions are connected to the pair of first sides of the main flat plate portion, respectively. The pair of first bent portions are provided between the main flat plate portion and the first flat plate portion along the pair of first sides of the main flat plate portion, respectively, and the first flat plate portion is predetermined with respect to the main flat plate portion. It is bent to form an angle.

  The manufacturing method which concerns on embodiment of this invention is a method of manufacturing the said square battery, and has process (i)-(iii). Step (i) is a step of arranging the electrical insulating sheet with respect to the electrode group in a state before the first bent portion is bent, and in step (i), a window formed in the main flat plate portion. Pass the electrode tab through. After step (i), in step (ii), the electrode tab is welded to the external terminal provided on the sealing plate while maintaining the electrical insulating sheet in the state before being bent. After step (ii), in step (iii), the electrode group is housed in an outer can and the opening of the outer can is sealed with a sealing plate. In step (iii), when the electrode group is accommodated in the outer can, the first flat plate portion is raised with respect to the main flat plate portion by bending the first bent portion of the electrical insulating sheet.

  According to the above manufacturing method, without using a long lead plate or the like conventionally used, before the electrode group is accommodated in the outer can, the electrode tab is passed through the window of the electrical insulating sheet, welding, etc. By this processing (step (ii)), the electrode tab and the external terminal can be connected to each other. Specifically, in step (ii), the electrical insulating sheet is maintained in a state before the first bent portion is bent. Therefore, the processing such as welding is not hindered by the electrical insulating sheet. And after processing such as welding, when the electrode group is accommodated in the outer can in the step (iii), by bending the first bent portion and raising the first flat plate portion relative to the main flat plate portion, In the prismatic battery, the first flat plate portion is disposed along the inner surface of the outer can. As a result, the first flat plate portion is interposed between the electrode tab and the outer can. Therefore, in the manufactured rectangular battery, even when the electrode tab is deformed by an external force generated by vibration or collision, the contact between the electrode tab and the outer can is prevented by the first flat plate portion. Therefore, in the rectangular battery, an electrical short circuit between the positive electrode and the negative electrode via the outer can is prevented. In addition, since the electrode tab and the external terminal can be connected to each other without using a conventionally long lead plate or the like, the volume energy density of the rectangular battery can be improved.

Next, the details of the prismatic battery according to the embodiment, the manufacturing method thereof, and the electrical insulating sheet used for the same will be specifically described with reference to the drawings.
[1] Configuration of Square Battery FIG. 1 is a perspective view conceptually showing the square battery of this embodiment. FIG. 2 is an exploded perspective view of the prismatic battery. The prismatic battery of this embodiment includes four electrode groups 1A to 1D, a bottomed cylindrical outer can 2, a sealing plate 3, a positive terminal member 4, a negative terminal member 5, and four positive lead plates. 6, four negative electrode lead plates 7, and an electrical insulating sheet 8. In the following, in a posture in which the opening 21 of the outer can 2 is directed upward (see FIG. 2), the width direction of the outer can 2 is the X direction, the thickness direction of the outer can 2 is the Y direction, and the height of the outer can 2 is high. The vertical direction is the Z direction. The Z direction coincides with the direction from the bottom surface 22 of the outer can 2 toward the opening 21. The outer can 2 has a front wall 231 in which the outer surface faces in a direction opposite to the Y direction in a posture in which the opening 21 faces in the Z direction, and a back in which the outer surface in the posture in which the opening 21 faces in the Z direction. A wall 232, a first side wall 233 whose outer surface faces in the direction opposite to the X direction with the opening 21 facing in the Z direction, and a second side wall whose outer surface faces in the X direction with the opening 21 facing in the Z direction. 234.

[1-1] Electrode Group FIG. 3 shows the internal structure of the prismatic battery (specifically, the connection structure of the positive electrode) as viewed from the first side wall 233 (see FIG. 2) of the outer can 2. It is a side view. 4 is a side view showing the internal structure of the prismatic battery (specifically, the connection structure of the negative electrode) when viewed from the second side wall 234 (see FIG. 2) of the outer can 2. 3 and 4, the illustration of the second flat plate portion 83 included in the electrical insulating sheet 8 described later is omitted. As shown in FIGS. 2 to 4, the electrode groups 1 </ b> A to 1 </ b> D are accommodated in the outer can 2 while being stacked in the Y direction. The outer can 2 contains an electrolyte together with the electrode groups 1A to 1D. The electrode groups 1 </ b> A to 1 </ b> D have an end face 13 that faces the opening 21 of the outer can 2 in the assembled state of the prismatic battery. The electrode groups 1A to 1D are respectively provided with positive electrode terminal portions 11A to 11D and negative electrode terminal portions 12A to 12D extending from the end face 13 toward the opening 21 (in the Z direction). In the present embodiment, the electrode groups 1A to 1D have the same configuration, shape, and dimensions. The end faces 13 of the electrode groups 1A to 1D are aligned on the same plane. Further, the height T1 of the positive electrode terminal portions 11A to 11D in the Z direction (see FIG. 3) and the height T2 of the negative electrode terminal portions 12A to 12D in the Z direction from the end surface 13 aligned on the same plane (see FIG. 4) is the same.

  Fig.5 (a) is the longitudinal cross-sectional view which showed notionally the structure of the positive electrode which each of electrode group 1A-1D has. FIG. 5B is a longitudinal sectional view conceptually showing the configuration of the negative electrode included in each of the electrode groups 1A to 1D. As shown in FIGS. 5A and 5B, in each of the electrode groups 1 </ b> A to 1 </ b> D, a plurality of positive plates 14 and a plurality of negative plates 15 are alternately stacked via separators 16. In the present embodiment, the number of the negative electrode plates 15 is one more than the number of the positive electrode plates 14, and the two outer layers are both constituted by the negative electrode plate 15. As an example, there are 30 positive plates 14 and 31 negative plates 15. In addition, the number of the positive electrode plates 14 and the number of the negative electrode plates 15 may be the same, one outer layer may be constituted by the positive electrode plate 14, and the other outer layer may be constituted by the negative electrode plate 15. Further, the number of the positive plates 14 may be one more than the number of the negative plates 15, and the two outer layers may be constituted by the positive plate 14.

  As shown in FIG. 5A, each of the positive plates 14 has an edge 141 facing the opening 21 (see FIG. 3) of the outer can 2 in the assembled state of the square battery. A positive electrode tab 142 protrudes from the end edge 141, and the positive electrode tab 142 is directed to the opening 21 (in the Z direction) in the assembled state of the rectangular battery. Further, the positive electrode tabs 142 respectively provided on the plurality of positive electrode plates 14 belonging to each of the electrode groups 1A to 1D protrude from the same position on the end edge 141 and overlap to form one bundle. And the bundle | flux formed in this way comprises each of positive electrode terminal part 11A-11D.

  In the present embodiment, the positive electrode tab 142 is provided at the same position on the edge 141 in all the positive electrode plates 14 included in the electrode groups 1A to 1D. Accordingly, two positive terminal portions selected from the four positive terminal portions 11A to 11D are opposed to each other in any combination. In addition, the position on the edge 141 which provides the positive electrode tab 142 may differ for every electrode group 1A-1D.

  As shown in FIG. 5B, each of the negative electrode plates 15 has an edge 151 that faces the opening 21 (see FIG. 3) of the outer can 2 in the assembled state of the rectangular battery. A negative electrode tab 152 protrudes from the edge 151, and the negative electrode tab 152 is directed to the opening 21 (in the Z direction) in the assembled state of the rectangular battery. Moreover, the negative electrode tabs 152 respectively provided on the plurality of negative electrode plates 15 belonging to each of the electrode groups 1A to 1D protrude from the same position on the edge 151 and overlap to form one bundle. And the bundle | flux formed in this way comprises each of negative electrode terminal part 12A-12D.

  In the present embodiment, the negative electrode tab 152 is provided at the same position on the edge 151 in all the negative electrode plates 15 included in the electrode groups 1A to 1D. Accordingly, two negative terminal portions selected from the four negative terminal portions 12A to 12D are opposed to each other in any combination. In addition, the position on the edge 151 which provides the negative electrode tab 152 may differ for every electrode group 1A-1D.

[1-2] Electrical Insulating Sheet FIG. 6A is a plan view showing the electrical insulating sheet 8. FIG.6 (b) is a principal part enlarged view of the cross section along the VIb-VIb line | wire shown by Fig.6 (a). FIGS. 7A and 7B are perspective views showing the state before and after the bending of the electrical insulating sheet 8. The electrical insulating sheet 8 is a sheet that prevents the positive electrode and the negative electrode from being electrically short-circuited inside the outer can 2, and is disposed between the electrode groups 1 </ b> A to 1 </ b> D and the sealing plate 3 as shown in FIG. 3. Has been placed. Specifically, as shown in FIGS. 2 and 6A, the electrical insulating sheet 8 includes a main flat plate portion 80, a pair of first flat plate portions 81, a pair of first bent portions 82, and a pair. The second flat plate portion 83 and a pair of second bent portions 84 are provided. The electrical insulating sheet 8 can be produced by a simple method such as punching of a large-sized electrical insulating sheet.

  Here, the main flat plate portion 80 has a substantially rectangular outer edge. The outer edge includes a pair of first sides 80a extending substantially in parallel and a pair of first sides 80a extending substantially perpendicular to the first side 80a. A second side 80b is included. The main flat plate portion 80 is not limited to the one having a strictly rectangular outer edge, and the main flat plate portion 80 is not only provided with a notch in the corner as in the present embodiment, but also with a rounded corner. There may be. Further, the main flat plate portion 80 is formed with a window 85 through which all the positive electrode terminal portions 11A to 11D pass and a window 86 through which all the negative electrode terminal portions 12A to 12D pass. In the rectangular battery, all the positive terminal portions 11A to 11D are passed through the window 85 and all the negative terminal portions 12A to 12D are passed through the window 86. In this state, the main flat plate portion 80 is passed. Faces the end face 13 of the electrode groups 1A to 1D. Further, in the rectangular battery, the main flat plate portion 80 is arranged so that the first side 80 a and the second side 80 b are along the inner surface of the outer can 2. Specifically, the main flat plate portion 80 has a pair of first sides 80a along the inner surfaces of the front wall 231 and the back wall 232, respectively, and a pair of second sides 80b of the first side wall 233 and the second side wall 234, respectively. It is arranged along the inner surface.

  The pair of first flat plate portions 81 are connected to the pair of first sides 80 a of the main flat plate portion 80, respectively. The pair of first bent portions 82 is provided between the main flat plate portion 80 and the first flat plate portion 81 along the pair of first sides 80 a of the main flat plate portion 80. The first bent portion 82 has a shape that allows the first flat plate portion 81 to rise substantially perpendicular to the main flat plate portion 80. Specifically, as shown in FIG. 6 (b), each of the first bent portions 82 has a V-shaped groove 82 a formed along the first side 80 a of the corresponding main flat plate portion 80. doing. Here, it is preferable that the two inner surfaces 82b constituting the V-shaped groove 82a form an angle θ of 90 ° or more and 120 ° or less. The depth d of the groove 82a is preferably 50% or more and 95% or less with respect to the thickness T of the electrical insulating sheet 8. The V-shaped groove 82a includes a groove having a rounded V-shaped tip and a U-shaped groove. The groove 82a may be a square groove.

  According to the shape of each of the first bent portions 82, the first flat plate portion 81 is formed by bending the first bent portion 82 so that the two inner surfaces 82b constituting the groove 82a are close to each other. It is raised substantially perpendicular to the main flat plate portion 80 (see FIGS. 7A and 7B). That is, the first flat plate portion 81 forms a predetermined angle (about 90 ° in the present embodiment) with respect to the main flat plate portion 80. In the prismatic battery, the first bent portion 82 is bent so that the first flat plate portion 81 forms such an angle with respect to the main flat plate portion 80. Thereby, a pair of 1st flat plate part 81 is each arrange | positioned along the inner surface of the front wall 231 and the back wall 232 of the exterior can 2 (refer FIG. 3).

  The pair of second flat plate portions 83 are connected to the pair of second sides 80 b of the main flat plate portion 80, respectively. The pair of second bent portions 84 are respectively provided between the main flat plate portion 80 and the second flat plate portion 83 along the pair of second sides 80 b of the main flat plate portion 80. The second bent portion 84 has a shape that allows the second flat plate portion 83 to rise substantially perpendicular to the main flat plate portion 80. Specifically, each of the second bent portions 84 has a V-shaped groove 84a formed along the second side 80b of the corresponding main flat plate portion 80 (see FIG. 6B). ). Here, the two inner surfaces 84b constituting the V-shaped groove 84a preferably form an angle θ of 90 ° or more and 120 ° or less. The depth d of the groove 84 a is preferably 50% or more and 95% or less with respect to the thickness T of the electrical insulating sheet 8. The V-shaped groove 84a includes a groove having a rounded V-shaped tip and a U-shaped groove. Further, the groove 84a may be a square groove.

  According to the shape of each of the second bent portions 84, the second flat plate portion 83 is formed by bending the second bent portion 84 so that the two inner surfaces 84b constituting the groove 84a are close to each other. It is raised substantially perpendicular to the main flat plate portion 80 (see FIGS. 7A and 7B). That is, the second flat plate portion 83 forms a predetermined angle (about 90 ° in the present embodiment) with respect to the main flat plate portion 80. In the square battery, the second bent portion 84 is bent so that the second flat plate portion 83 forms such an angle with respect to the main flat plate portion 80. As a result, the pair of second flat plate portions 83 are arranged along the inner surfaces of the first side wall 233 and the second side wall 234 of the outer can 2, respectively.

  In order to prevent the positive electrode and the negative electrode from being electrically short-circuited inside the outer can 2, a distance L (from the end surface 13 of the electrode group 1 </ b> A to 1 </ b> D to the inner surface 31 of the sealing plate 3 in the square battery is provided. 3), the width W1 of the first flat plate portion 81 and the width W2 of the second flat plate portion 83 (see FIG. 6A) preferably have the following relationship. That is, the width W1 is a value close to the distance L in a range in which a part of the first flat plate portion 81 does not protrude from the opening 21 of the outer can 2 when the electrical insulating sheet 8 is accommodated in the outer can 2. It is preferable. Similarly, the width W2 is a value close to the distance L in a range in which a part of the second flat plate portion 83 does not protrude from the opening 21 of the outer can 2 when the electrical insulating sheet 8 is accommodated in the outer can 2. Preferably there is.

[1-3] Sealing Plate As shown in FIG. 3, the opening 21 of the outer can 2 is sealed with the sealing plate 3. Specifically, the sealing plate 3 has an outer edge shape slightly larger than the shape of the opening 21 of the outer can 2 and is fixed to the opening end surface of the outer can 2 by welding means such as laser welding. Thus, the opening 21 of the outer can 2 is preferably sealed by the sealing plate 3. This prevents liquid leakage from the prismatic battery and entry of foreign matter into the prismatic battery.

[1-4] Positive Terminal Member and Negative Terminal Member As shown in FIG. 3, the positive terminal member 4 includes a positive base portion 41 and a positive external terminal 42. Here, the positive electrode base portion 41 is a flat plate having a rectangular shape. The positive electrode external terminal 42 is a bolt having a thread groove (not shown), and protrudes from the main surface 411 of the positive electrode base portion 41.

  As shown in FIG. 2, the positive terminal member 4 is provided on the sealing plate 3. Specifically, as shown in FIG. 3, the positive external terminal 42 penetrates the sealing plate 3 from the inner surface 31 side, and the nut 32 is fitted to the positive external terminal 42 in this state. The nut 32 is tightened toward the base of the positive electrode external terminal 42. Accordingly, the positive electrode base portion 41 is urged toward the inner surface 31 of the sealing plate 3 and is fixed to the sealing plate 3, and as a result, the positive electrode terminal member 4 is fixed to the sealing plate 3. A seal member 43 such as a gasket is interposed between the positive electrode base portion 41 and the sealing plate 3 and between the nut 32 and the sealing plate 3. Further, the seal member 43 is also interposed between the positive electrode external terminal 42 and the sealing plate 3 to prevent electrical contact therebetween.

  As shown in FIG. 4, the negative electrode terminal member 5 has a negative electrode base portion 51 and a negative electrode external terminal 52. In the present embodiment, the negative electrode terminal member 5 has the same shape and size as the positive electrode terminal member 4. The negative electrode terminal member 5 may have a shape and dimensions different from those of the positive electrode terminal member 4.

  As shown in FIG. 2, the negative electrode terminal member 5 is provided on the sealing plate 3. Specifically, as shown in FIG. 4, the negative electrode external terminal 52 penetrates the sealing plate 3 from the inner surface 31 side, and the nut 33 is fitted to the negative electrode external terminal 52 in this state. A seal member 53 such as a gasket is interposed between the negative electrode base portion 51 and the sealing plate 3 and between the nut 33 and the sealing plate 3. Further, the sealing member 53 is also interposed between the negative electrode external terminal 52 and the sealing plate 3 to prevent electrical contact therebetween.

[1-5] Positive Electrode Lead Plate and Negative Electrode Lead Plate As shown in FIG. 3, the end portions of the positive electrode lead plate 6 are electrically connected to the positive electrode terminal portions 11A to 11D by means such as welding. These positive electrode lead plates 6 are bundled into one, and the tip of the formed bundle is electrically connected to the surface 412 of the positive electrode base portion 41 opposite to the main surface 411 by means such as welding. It is connected to the. The bundle of positive electrode lead plates 6 is folded in a space in the outer can 2 provided between the electrode groups 1 </ b> A to 1 </ b> D and the sealing plate 3. In this way, the positive electrode terminal portions 11 </ b> A to 11 </ b> D are electrically connected to the positive electrode external terminal 42 through the positive electrode lead plate 6.

  As shown in FIG. 4, the end portions of the negative electrode lead plate 7 are electrically connected to the negative electrode terminal portions 12A to 12D by means such as welding. These negative electrode lead plates 7 are bundled together, and the tip of the formed bundle is electrically connected to the negative electrode base portion 51 by means such as welding. The bundle of negative electrode lead plates 7 is folded in a space in the outer can 2 provided between the electrode groups 1 </ b> A to 1 </ b> D and the sealing plate 3. In this manner, the negative electrode terminal portions 12 </ b> A to 12 </ b> D are electrically connected to the negative electrode external terminal 52 through the negative electrode lead plate 7.

  According to the prismatic battery of the present embodiment, when the electrical insulating sheet 8 is accommodated in the outer can 2 in the manufacturing process as described later, the electrical insulating sheet 8 is connected to the windows 85 and 86 at the positive terminal portions 11A to 11A. 11D and the negative electrode terminal portions 12A to 12D are arranged with respect to the electrode groups 1A to 1D so as to pass therethrough. Further, the first bent portion 82 and the second bent portion 84 are bent, and the first flat plate portion 81 and the second flat plate portion 83 are raised with respect to the main flat plate portion 80, respectively. Thereby, the 1st flat plate part 81 and the 2nd flat plate part 83 are arrange | positioned along the inner surface of the armored can 2 in a square battery. Specifically, the pair of first flat plate portions 81 are arranged along the inner surfaces of the front wall 231 and the back wall 232 of the outer can 2 (see FIG. 3). The pair of second flat plate portions 83 are disposed along the inner surfaces of the first side wall 233 and the second side wall 234 of the outer can 2. As a result, the first flat plate portion 81 and the second flat plate portion 83 are interposed between the positive electrode terminal portions 11A to 11D and the outer can 2 and between the negative electrode terminal portions 12A to 12D and the outer can 2. . Therefore, in the rectangular battery, even when the positive electrode terminal portions 11A to 11D and the negative electrode terminal portions 12A to 12D are deformed by an external force generated by vibration or collision, the contact between these terminal portions and the outer can 2 is the first flat plate portion. This is prevented by 81 and the second flat plate portion 83. In addition, contact between the positive electrode lead plate 6 and the negative electrode lead plate 7 and the outer can 2 is also prevented. Therefore, in the rectangular battery, an electrical short circuit between the positive electrode and the negative electrode via the outer can 2 is prevented. The electrical insulating sheet 8 facilitates the prevention of such an electrical short circuit.

[2] Method for Producing Square Battery In the method for producing a square battery according to this embodiment, a preparation process, a first accommodation process, a second accommodation process, a welding process, and a sealing process are sequentially executed. Is done. Details of each step will be described below.

[2-1] Preparation Step First, in the preparation step, the electrical insulating sheet 8 is prepared (see FIGS. 2, 6A and 6B). Specifically, by punching the large-sized electrical insulating sheet or the like, the large-sized electrical insulating sheet is punched into a predetermined shape, and grooves 82a and 84a are formed at predetermined locations.

  In the preparation step, in addition to the electrical insulating sheet 8, the electrode groups 1A to 1D provided with the positive electrode terminal portions 11A to 11D and the negative electrode terminal portions 12A to 12D, respectively, and the exterior housing these electrode groups 1A to 1D A can 2 and a sealing plate 3 for sealing the opening 21 of the outer can 2 are prepared. Further, the positive electrode lead plate 6 is electrically connected to each of the positive electrode terminal portions 11A to 11D using means such as welding, and the negative electrode lead plate 7 is electrically connected to each of the negative electrode terminal portions 12A to 12D. . Furthermore, the positive terminal member 4 and the negative terminal member 5 are fixed to the sealing plate 3 using nuts 32 and 33.

[2-2] First Accommodation Step FIG. 8 is a perspective view used for explaining the first accommodation step. As shown in FIG. 8, in the first housing step, the electrode groups 1 </ b> A to 1 </ b> D are housed in the outer can 2 such that their end surfaces 13 face the openings 21 of the outer can 2. At this time, the positive electrode terminal portions 11A to 11D are opposed to each other by the positive electrode terminal portions, and the negative electrode terminal portions 12A to 12D are opposed to each other by the negative electrode terminal portions.

  After the electrode groups 1A to 1D are accommodated in the outer can 2, the positive electrode lead plates 6 are bundled together as shown in FIG. In addition, the bundle of the positive electrode lead plates 6 is creased so that the positive electrode lead plates 6 can be easily folded in the sealing process described later. The crease may be attached immediately before the positive electrode lead plate 6 is folded in the sealing process.

  Similarly, the negative electrode lead plates 7 are also bundled together. In addition, the bundle of the negative electrode lead plates 7 is creased so that the negative electrode lead plates 7 can be easily folded in a sealing process described later. Note that the crease may be provided immediately before the negative electrode lead plate 7 is folded in the sealing step.

[2-3] Second Housing Process FIGS. 9, 10A and 10B are perspective views used for explaining the second housing process. In the second accommodation step, first, as shown in FIG. 9, the electrical insulating sheet 8 is prepared in a state before the first bent portion 82 and the second bent portion 84 are bent, and the window 85 of the electric insulating sheet 8 is prepared. And 86, the bundle of the positive electrode lead plate 6 and the bundle of the negative electrode lead plate 7 are respectively passed.

  Next, as shown in FIG. 10A, the first flat plate portion 81 and the second flat portion 80 are bent with respect to the main flat plate portion 80 by bending the first bent portion 82 and the second bent portion 84 of the electrical insulating sheet 8. 2 The flat plate portions 83 are respectively raised in the Z direction, and the electrical insulating sheet 8 is slid into the outer can 2 in this state. In this way, the electrical insulating sheet 8 is accommodated in the outer can 2 as shown in FIG. Accordingly, all the positive terminal portions 11A to 11D are passed through the window 85, and all the negative terminal portions 12A to 12D are passed through the window 86. In this state, the main flat plate portion 80 is connected to the electrode groups 1A to 1D. Opposite the end face 13. Also, the pair of first flat plate portions 81 are respectively disposed along the inner surfaces of the front wall 231 and the back wall 232 of the outer can 2, and the pair of second flat plate portions 83 are respectively disposed on the first side wall 233 and the outer can 2. The second side wall 234 is disposed along the inner surface.

[2-4] Welding Process FIG. 11 is a perspective view used for explaining the welding process. As shown in FIG. 11, in the welding process, a sealing plate 3 to which the positive electrode terminal member 4 and the negative electrode terminal member 5 are fixed is prepared. Then, using a means such as welding, the tip of the bundle of positive electrode lead plates 6 is electrically connected to the positive electrode base portion 41 and the tip of the bundle of negative electrode lead plates 7 is electrically connected to the negative electrode base portion 51. Connect (see FIGS. 3 and 4).

[2-5] Sealing Step In the sealing step, the bundle of the positive electrode lead plate 6 and the bundle of the negative electrode lead plate 7 are folded and accommodated in the outer can 2, and the sealing plate 3 is brought into contact with the opening end surface of the outer can 2. (See FIGS. 3 and 4). Then, with the sealing plate 3 in contact with the opening end surface of the outer can 2, the contact surface between the outer can 2 and the sealing plate 3 is subjected to welding such as laser welding, thereby opening the opening 21 of the outer can 2 to the sealing plate. 3 to seal.

  According to the manufacturing method of the present embodiment, even when the positive electrode terminal portions 11A to 11D and the negative electrode terminal portions 12A to 12D are deformed by an external force generated by vibration or collision in the manufactured rectangular battery, Contact with the outer can 2 is prevented by the first flat plate portion 81 and the second flat plate portion 83. In addition, contact between the positive electrode lead plate 6 and the negative electrode lead plate 7 and the outer can 2 is also prevented. Therefore, in the rectangular battery, an electrical short circuit between the positive electrode and the negative electrode via the outer can 2 is prevented.

[3] Modification [3-1] First Modification In the prismatic battery of the above embodiment, after the electrode groups 1A to 1D are accommodated in the outer can 2, the positive electrode lead plate 6 is bundled into one and the positive electrode terminal It was necessary to connect to the member 4 and to bundle the negative electrode lead plate 7 into one and connect it to the negative electrode terminal member 5. This is because if these connections are made before the electrode groups 1A to 1D are accommodated in the outer can 2, the stacked electrode groups 1A to 1D will be misaligned. If the electrode groups 1 </ b> A to 1 </ b> D are displaced before being accommodated in the outer can 2, it is difficult to accommodate the electrode groups 1 </ b> A to 1 </ b> D in the outer can 2.

  For this reason, the electrode groups 1A to 1D need to be accommodated in the outer can 2 first. Therefore, the electrode groups 1A to 1D are accommodated in the outer can 2 as the positive electrode lead plate 6 and the negative electrode lead plate 7. Sometimes it was necessary to use a long one that could be pulled out of the outer can 2. For this reason, it is necessary to provide a space for folding and housing the positive electrode lead plate 6 and the negative electrode lead plate 7 in the outer can 2. However, such a space hinders the improvement of the volume energy density of the prismatic battery.

  In order to improve the volumetric energy density of the prismatic battery, it has been proposed to use another connecting member instead of the long lead plate. This connection member is an electrode with respect to the positive electrode terminal member 4 and the negative electrode terminal member 5 without causing positional displacement in the electrode groups 1A to 1D even before the electrode groups 1A to 1D are accommodated in the outer can 2. The groups 1A to 1D can be electrically connected. However, if the conventionally proposed electrically insulating frame (see, for example, Patent Document 2) is used in a square battery manufactured by this technique, the following problems occur. That is, in the manufacturing process, the positive electrode terminal member 4 and the negative electrode with respect to the electrode groups 1A to 1D by processing such as welding in a state where the positive electrode terminal portions 11A to 11D are passed through the windows provided in the bottom plate portion of the frame body. When the terminal member 5 is to be connected, the processing is hindered by the frame (mainly the side wall).

  The electrical insulating sheet 8 described above is particularly preferable for such a square battery. This is because even if the positive electrode terminal portions 11A to 11D and the negative electrode terminal portions 12A to 12D are passed through the windows 85 and 86 of the electrical insulating sheet 8, the positive electrode terminals 1A to 1D are positively connected to the electrode groups 1A to 1D by processing such as welding. This is because the terminal member 4 and the negative electrode terminal member 5 can be connected. Here, for this connection, an electrical connection between the positive electrode connecting member used in place of the positive electrode lead plate 6 and the positive electrode terminal portions 11A to 11D, an electric connection between the positive electrode connecting member and the positive electrode terminal member 4, Electrical connection between the negative electrode connecting member used in place of the negative electrode lead plate 7 and the negative electrode terminal portions 12A to 12D and connection between the negative electrode connecting member and the negative electrode terminal member 5 are included.

  Specifically, when processing such as welding, the electrical insulating sheet 8 is maintained in a state before the first bent portion 82 and the second bent portion 84 are bent. Thereby, processes, such as welding, are not disturbed by the electrical insulating sheet 8.

  And after processing, such as welding, when accommodating electrode group 1A-1D in the armored can 2, the 1st bending part 82 and the 2nd bending part 84 are bent, and it is 1st flat plate with respect to the main flat plate part 80. By raising the portion 81 and the second flat plate portion 83, the first flat plate portion 81 and the second flat plate portion 83 are arranged along the inner surface of the outer can 2 in the outer can 2. Therefore, as in the case of the prismatic battery of the above embodiment, even when the positive terminal portions 11A to 11D and the negative terminal portions 12A to 12D are deformed by an external force generated by vibration or collision, the contact between these terminal portions and the outer can 2 is achieved. Is prevented by the first flat plate portion 81 and the second flat plate portion 83. Therefore, in the rectangular battery, an electrical short circuit between the positive electrode and the negative electrode via the outer can 2 is prevented.

[3-2] Second Modification FIG. 12A is a plan view showing a modification of the electrical insulating sheet 8. FIG.12 (b) is the principal part enlarged view of the cross section which follows the XIIb-XIIb line | wire shown by Fig.12 (a). As shown in FIG. 12 (b), the electrical insulating sheet 8 has a sheet surface 8 a including the surface of the main flat plate portion 80 and a sheet back surface 8 b including the back surface of the main flat plate portion 80. In the electrical insulating sheet 8 of this modification, each of the first bent portions 82 has two grooves 82c and 82d formed on the sheet surface 8a and the sheet back surface 8b, respectively. Here, the grooves 82c and 82d extend along the first side 80a (see FIG. 12A) of the corresponding main flat plate portion 80 and face each other. In this modification, the grooves 82c and 82d have the same shape with rounded V-shaped tips, and each inner surface includes a curved surface 82e constituting the rounded portion and two flat surfaces 82f connected to both ends thereof. It is configured. The curvature radius of the curved surface 82e is preferably 0.3 mm or more and 5 mm or less. The angle θ formed by the two planes 82f is preferably 90 ° or more and 120 ° or less. The grooves 82c and 82d may have different shapes.

  Further, in each of the first bent portions 82, the groove 82 c is formed with a plurality of through holes 82 h that communicate with the groove 82 d and a notch 82 i that retreats the end of the groove 82 c from the end of the first flat plate portion 81. Has been. In this modification, the through holes 82h are formed at an equal pitch. Each of the through holes 82h is preferably opened such that the width W3 in the longitudinal direction of the groove 82c is larger than the width W4 in the short direction of the groove 82c. Each of the through holes 82h preferably has the same width as the groove 82c in the short direction of the groove 82c. In addition, these aspects are preferable examples, in which the through holes 82h are arranged at different pitches, or in each of the through holes 82h, the width W3 is the same as or smaller than the width W4. Does not exclude an aspect in which the width W4 is different from the width of the groove 82c in each of the through holes 82h.

  Each of the second bent portions 84 has two grooves 84c and 84d formed in the sheet surface 8a and the sheet back surface 8b, respectively. Here, the grooves 84c and 84d extend along the second side 80b (see FIG. 12A) of the corresponding main flat plate portion 80 and face each other. Like the grooves 82c and 82d, the grooves 84c and 84d have the same shape with rounded V-shaped tips, and each inner surface has a curved surface 82e that forms a rounded portion, and two planes 82f that connect to both ends thereof. It consists of and. The grooves 84c and 84d may have different shapes.

  Further, in each of the second bent portions 84, the groove 84 c is formed with a through hole 84 h communicating with the groove 84 d and a notch 84 i for retracting the end of the groove 84 c from the end of the second flat plate portion 83. Yes. In this modification, one through hole 84h is formed at the center in the longitudinal direction of the groove 84c. The through hole 84h is preferably opened so that the width W5 in the longitudinal direction of the groove 84c is larger than the width W6 in the short direction of the groove 84c. The through hole 84h preferably has the same width as the groove 84c in the short direction of the groove 84c. These modes are preferable examples, and a mode in which a plurality of through holes 84h are formed in the groove 84c, a mode in which the width W5 is the same as or smaller than the width W6 in the through holes 84h, In the through hole 84h, an aspect in which the width W6 is different from the width of the groove 84c is not excluded.

  In the embodiment described above, the V-shaped grooves 82a and 84a are formed only on one side. For this reason, the greater the depth d of the grooves 82a and 84a, the easier the bending of the first bent portion 82 and the second bent portion 84 becomes. On the other hand, in order to increase the depth d, it is necessary to perform cutting on the punched sheet after punching the large-sized electrical insulating sheet. Such a manufacturing method complicates the manufacturing and increases the manufacturing cost. On the other hand, if the electrical insulation sheet 8 can be formed by resin molding using a mold, the production of the electrical insulation sheet 8 is simplified and the production cost is reduced. However, in resin molding using a mold, it is difficult to increase the depth d of the grooves 82a and 84a.

  Therefore, according to the electrical insulating sheet 8 of the present modification, each of the depths d of the grooves 82c and 82d (FIG. 12) is compared with the case where the V-shaped groove 82a is formed on one side as in the above-described embodiment. (See (b)) can be reduced. Further, the depth d of each of the grooves 84c and 84d can be reduced as compared with the case where the V-shaped groove 84a is formed on one side as in the above-described embodiment. Therefore, the electrical insulating sheet 8 can be manufactured by a simple method such as resin molding using a mold. From the viewpoint of enabling the production of the electrical insulating sheet 8 using a mold, the depth d of each of the grooves 82c and 82d and the grooves 84c and 84d is the thickness T of the electrical insulating sheet 8 (FIG. 12B). It is preferable that it is 15% or more and 40% or less. The total depth of the two grooves 82c and 82d facing each other and the total depth of the two grooves 84c and 84d facing each other are 30% or more and 80% with respect to the thickness T of the electrical insulating sheet 8, respectively. The following is preferable.

  Furthermore, in the electrical insulating sheet 8 of the present modification, the first bent portion 82 can be easily bent due to the presence of the through hole 82h. Further, by further providing the notch 82i, the first bent portion 82 can be bent more easily. Similarly, the second bent portion 84 can be easily bent by the presence of the through hole 84h and the notch 84i. Therefore, according to the electrical insulating sheet 8 of the present modification, it is possible to achieve both the production by resin molding using a mold and easy bending.

  In addition, each part structure of this invention is not restricted to the said embodiment and said modification, A various deformation | transformation is possible within the technical scope as described in a claim. For example, in the rectangular battery, the electrical insulating sheet 8 may have a configuration without the second flat plate portion 83 and the second bent portion 84.

  In the prismatic battery, the positive electrode terminal member 4 and the positive electrode lead plate 6 (or positive electrode connecting member) are not provided, and the positive electrode plate 14 included in each of the electrode groups 1A to 1D is an inner surface of the outer can 2 having conductivity. May be electrically connected. In this case, at least a part of the outer peripheral surface of the outer can 2 is used as a positive external terminal. Further, the electrical insulating sheet 8 may not have the window 85.

  In the prismatic battery, the negative electrode terminal member 5 and the negative electrode lead plate 7 (or the negative electrode connecting member) are not provided, and the negative electrode plate 15 included in each of the electrode groups 1A to 1D is an inner surface of the outer can 2 having conductivity. May be electrically connected. In this case, at least a part of the outer peripheral surface of the outer can 2 is used as a negative electrode external terminal. The electrical insulating sheet 8 may not have the window 86.

  Furthermore, each part structure of the said square battery is applicable to various secondary batteries, such as a lead storage battery, a lithium ion battery, and a molten salt battery, if an electrode group is a square battery accommodated in an exterior can. . Moreover, each part structure of the said square battery may be applied to a primary battery.

  The prismatic battery and the manufacturing method thereof according to the present invention are useful for, for example, a household or industrial large power storage device, and a power source mounted in an electric vehicle or a hybrid vehicle.

1A, 1B, 1C, 1D Electrode group 11A, 11B, 11C, 11D Positive terminal portion 12A, 12B, 12C, 12D Negative terminal portion 13 End face 14 Positive plate 141 Edge 142 Positive electrode tab 15 Negative electrode plate 151 Edge 152 Negative electrode tab 16 Separator 2 Exterior can 21 Opening 22 Bottom surface 231 Front wall 232 Back wall 233 First side wall 234 Second side wall 3 Sealing plate 31 Inner surface 32, 33 Nut 4 Positive electrode terminal member 41 Positive electrode base portion 411 Main surface 412 Surface 42 Positive electrode external terminal 43 Seal Member 5 Negative electrode terminal member 51 Negative electrode base portion 52 Negative electrode external terminal 53 Seal member 6 Positive electrode lead plate 7 Negative electrode lead plate 8 Electrical insulating sheet 8a Sheet surface 8b Sheet back surface 80 Main flat plate portion 80a First side 80b Second side 81 First flat plate Portion 82 first bent portion 82a groove 82b inner surface 82c, 82d groove 82e curved surface 82f plane 82 h Through hole 82i Notch 83 Second flat plate portion 84 Second bent portion 84a Groove 84b Inner surface 84c, 84d Groove 84h Through hole 84i Notches 85, 86 Window L Distance T1, T2 Height θ Angle d Depth T Thickness W1, W2, W3, W4, W5, W6 Width 101 Electrode group 102 Exterior can 102a Opening 103 Sealing plate 104 Positive electrode external terminal 105 Positive electrode terminal portion 106 Positive electrode lead plate

Claims (6)

Sealing an electrode group in which a plurality of first electrode plates and a plurality of second electrode plates are stacked via a separator, a bottomed cylindrical outer can in which the electrode group is accommodated, and an opening of the outer can A plurality of electrode tabs respectively provided on the plurality of first electrode plates from the end face of the electrode group facing the opening of the outer can. In the prismatic battery that protrudes and the external terminal and the electrode tab are electrically connected to each other, an electrical insulating sheet disposed between the electrode group and the sealing plate,
The electrode group includes an outer edge including a pair of first sides extending substantially in parallel and a window through which the electrode tab is passed, and the electrode group is passed through the window in the rectangular battery. A main flat plate portion that faces the end surface and is arranged so that the first side is along the inner surface of the outer can.
A pair of first flat plate portions respectively connected to the pair of first sides of the main flat plate portion;
A square type having a pair of first bent portions provided along the pair of first sides of the main flat plate portion and allowing the first flat plate portion to stand up with respect to the main flat plate portion. Electric insulation sheet for batteries. The sheet insulation surface including the surface of the main flat plate portion and the sheet back surface including the back surface of the main flat plate portion is an electrical insulating sheet for a square battery according to claim 1,
Each of the first bent portions has a V-shaped groove formed on at least one of the sheet surface and the sheet back surface along the first side of the main flat plate portion. Electric insulation sheet for batteries.   The electrical insulating sheet for a prismatic battery according to claim 2, wherein at least one through hole is formed in each of the grooves. The outer edge of the main flat plate portion further includes a pair of second sides extending substantially perpendicular to the first side,
In addition to the first flat plate portion and the first bent portion,
A pair of second flat plate portions respectively connected to the pair of second sides of the main flat plate portion;
And a pair of second bent portions that are provided along the pair of second sides of the main flat plate portion and allow the second flat plate portion to rise with respect to the main flat plate portion. Item 4. The electrical insulating sheet for prismatic battery according to any one of Items 1 to 3. An electrode group in which a plurality of first electrode plates and a plurality of second electrode plates are laminated via a separator;
A bottomed cylindrical outer can containing the electrode group;
A sealing plate sealing the opening of the outer can;
An external terminal provided on the sealing plate;
An electrical insulating sheet disposed between the electrode group and the sealing plate;
A plurality of electrode tabs respectively provided on the plurality of first electrode plates protrude from the end face of the electrode group facing the opening of the outer can, and the external terminal and the electrode tab are electrically connected to each other. And
The electrical insulating sheet is
An outer edge including a pair of first sides extending substantially in parallel and a window through which the electrode tab is passed, facing the end surface of the electrode group, and the first side on the inner surface of the outer can A main flat plate portion arranged along
A pair of first flat plate portions respectively connected to the pair of first sides of the main flat plate portion;
The first flat plate portion is provided between the main flat plate portion and the first flat plate portion along the pair of first sides of the main flat plate portion, and the first flat plate portion forms a predetermined angle with respect to the main flat plate portion. A square battery having a pair of first bent portions bent in a similar manner. A method for manufacturing the prismatic battery according to claim 5, comprising:
(I) a step of arranging the electrical insulating sheet with respect to the electrode group in a state before the first bent portion is bent, wherein the electrode tab is formed on the window formed in the main flat plate portion; Passing the process,
(Ii) after the step (i), the step of welding the electrode tab to the external terminal provided on the sealing plate while maintaining the electrical insulating sheet in the state before being bent;
(Iii) After the step (ii), the electrode group is housed in the outer can, and the opening of the outer can is sealed with the sealing plate,
In the step (iii), when the electrode group is accommodated in the outer can, the first flat plate portion is raised with respect to the main flat plate portion by bending the first bent portion of the electrical insulating sheet. A method for manufacturing a rectangular battery.

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