Electricity storage unit

Abstract

Provided is a power storage unit capable of reducing the housing space of a collector tab. The power storage cell includes an electrode body, an insulating plate, and a power storage cell case. The electrode body has a plurality of electrodes and a separator. Each electrode has a collector foil and an active material layer. The electrode body includes: an electrode body main body disposed such that a portion of a collector foil where an active material layer is provided is arranged in one direction with a separator therebetween; and a plurality of collector tabs configured from a portion of the collector foil where the active material layer is not provided. Each of the collector tabs is bent in a state in which a portion of the collector tab overlaps a collector tab adjacent to the collector tab. The insulating plate has a base portion and a thickness adjusting portion provided at an end portion of the base portion in the second direction. The thickness adjusting portion gradually becomes thinner toward the inner side in the second direction.

Description

Technical Field

[0001] The present disclosure relates to a power storage unit. Background Art

[0002] International Publication No. 2009 / 031442 discloses a laminated battery having a stacked electrode body, a current collector lead plate, and a battery can. The stacked electrode body has a collector lug group formed by bundling a plurality of collector lugs. The collector lug group is welded to the lower surface of the current collector lead plate. The current collector lead plate is welded to the lower end of an external terminal provided on the battery can. Summary of the invention

[0003] In the stacked power storage unit described in International Publication No. 2009 / 031442, since a plurality of collector tabs need to be bundled, each collector tab becomes long, and thus a large space is required in the battery case to accommodate the collector tab group formed by bundling the plurality of collector tabs.

[0004] An object of the present disclosure is to provide a power storage unit capable of reducing the storage space for a collector tab.

[0005] According to one aspect of the present disclosure, a storage cell comprises: an electrode body; an insulating plate arranged in contact with the electrode body; and a storage cell case accommodating the electrode body and the insulating plate, the electrode body comprising: a plurality of electrodes arranged in a direction; and a separator insulated between the plurality of electrodes, each of the plurality of electrodes comprising: a collector foil; and an active material layer provided on the collector foil, the electrode body comprising: an electrode body main body arranged so that the portion of the collector foil on which the active material layer is provided is arranged in the direction across the separator; and a plurality of collector tabs extending from the collector foil The electrode body is formed in a portion where the active material layer is not provided, protruding from the electrode body in a first direction orthogonal to the one direction, and arranged in a manner of being arranged in a second direction orthogonal to both the one direction and the first direction, and each of the plurality of collector ears is bent in a state in which a portion of the collector ear overlaps with a collector ear adjacent to the collector ear, and the insulating plate comprises: a base portion, which is arranged between the electrode body and the plurality of collector ears; and a thickness adjustment portion, which is arranged at an end portion of the base portion in the second direction, and the thickness adjustment portion gradually becomes thinner as it goes to the inner side in the second direction.

[0006] The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1This is a perspective view schematically showing an electric storage unit in one embodiment of the present disclosure.

[0008] Figure 2 yes Figure 1 A cross-sectional view of a power storage unit shown.

[0009] Figure 3 is an enlarged cross-sectional view of a portion of the electrode body.

[0010] Figure 4 It is a cross-sectional view showing a modified example of the power storage unit. DETAILED DESCRIPTION

[0011] The embodiments of the present disclosure will be described with reference to the accompanying drawings. In the drawings referred to below, the same or corresponding components are denoted by the same reference numerals.

[0012] Figure 1 This is a perspective view schematically showing an electric storage unit in one embodiment of the present disclosure. Figure 2 yes Figure 1 A cross-sectional view of a power storage unit shown.

[0013] like Figure 1 and Figure 2 As shown, the storage cell 1 includes an electrode body 100 , a pair of insulating plates 150 , a storage cell case 200 , an electrolyte (not shown), a pair of external terminals 300 , a pair of connecting members 400 , and an insulating member 500 .

[0014] Figure 3 is an enlarged cross-sectional view of a portion of the electrode body. Figure 3 As shown, the electrode body 100 includes a plurality of electrodes 110 and 120 and a separator 130 .

[0015] like Figure 3 As shown, the plurality of electrodes 110, 120 are arranged in a direction ( Figure 3 The plurality of electrodes 110 and 120 include a plurality of positive electrodes 110 and a plurality of negative electrodes 120.

[0016] Each positive electrode 110 is formed in a rectangular shape that is long in the width direction (directions perpendicular to both the one direction and the up-down direction). Each positive electrode 110 includes a positive current collector foil 112 and positive active material layers 114 provided on both surfaces of the positive current collector foil 112 .

[0017] Each negative electrode 120 is formed in a rectangular shape that is long in the width direction. Each negative electrode 120 includes a negative electrode current collector foil 122 and a negative electrode active material layer 124 provided on both surfaces of the negative electrode current collector foil 122 .

[0018] The separator 130 insulates the positive electrode 110 from the negative electrode 120. The separator 130 is made of an insulating material and has minute gaps that allow ions to pass through.

[0019] like Figure 2 and Figure 3 As shown, the electrode body 100 includes an electrode body main body 101 and a plurality of current collecting tabs 112p, 122n.

[0020] The electrode body 101 is arranged so that the portions of the collector foils 112 and 122 where the active material layers 114 and 124 are provided are aligned in one direction with the separator 130 interposed therebetween.

[0021] Each collector tab 112p, 122n is formed by a portion of the collector foil 112, 122 where the active material layer 114, 124 is not provided, and protrudes from the electrode body main body 101 in the first direction (in the vertical direction in this embodiment). Specifically, the plurality of collector tabs 112p, 122n includes a plurality of positive electrode tabs 112p and a plurality of negative electrode tabs 122n. Each positive electrode tab 112p protrudes from the electrode body main body 101 toward one side in the first direction. Each negative electrode tab 122n protrudes from the electrode body main body 101 toward the other side in the first direction.

[0022] The plurality of collector tabs 112p and 122n are arranged in a second direction (in the present embodiment, the width direction) perpendicular to both the first direction and the first direction. Each collector tab 112p and 122n is bent so that a portion of the collector tab 112p and 122n overlaps with a collector tab adjacent to the collector tab 112p and 122n.

[0023] Each insulating plate 150 is disposed in contact with the electrode body 100. One of the pair of insulating plates 150 is disposed between the electrode body 101 and the plurality of positive electrode tabs 112p, and the other of the pair of insulating plates 150 is disposed between the electrode body 101 and the plurality of negative electrode tabs 122n.

[0024] like Figure 2 As shown, each insulating plate 150 has a base portion 152 and a thickness adjustment portion 154 .

[0025] The base portion 152 is disposed between the electrode body main body 101 and the plurality of current collecting tabs 112p and 122n. The base portion 152 is formed in a flat plate shape.

[0026] The thickness adjusting portion 154 is provided at the end portion of the base portion 152 in the second direction. The thickness adjusting portion 154 gradually becomes thinner as it goes toward the inner side in the second direction.

[0027] The battery cell case 200 accommodates the electrode assembly 100 . An electrolyte solution (not shown) is accommodated in the battery cell case 200 . The battery cell case 200 is sealed. The battery cell case 200 includes a case body 210 and a cover 220 .

[0028] The case body 210 has an opening 210a (see FIG. 21A ) protruding from the electrode body 101 toward each positive electrode tab 112p. Figure 2 In this embodiment, the opening 210a opens upward. The housing body 210 is made of a metal such as aluminum. Figure 2 As shown, the housing body 210 has a bottom wall 212 and a peripheral wall 214. The bottom wall 212 is formed in a rectangular and flat plate shape. The peripheral wall 214 stands from the bottom wall 212. The peripheral wall 214 is formed in a square tube shape. The upper end of the peripheral wall 214 constitutes an opening 210a. The length of the peripheral wall 214 in the width direction is longer than the length of the peripheral wall 214 in the thickness direction. The length of the peripheral wall 214 in the height direction is longer than the length of the peripheral wall 214 in the thickness direction.

[0029] The cover 220 closes the opening 210 a of the housing body 210 . The cover 220 is connected to the opening 210 a by welding or the like. The cover 220 is formed in a flat plate shape. The cover 220 is made of a metal such as aluminum. The cover 220 has a pressure release valve 222 and a sealing member 224 .

[0030] The pressure release valve 222 is formed in the center of the cover 220. The pressure release valve 222 is formed so that the pressure release valve 222 ruptures when the internal pressure of the battery cell case 200 becomes equal to or higher than a predetermined pressure. When the pressure release valve 222 ruptures, the gas in the battery cell case 200 is released to the outside of the battery cell case 200 through the pressure release valve 222, so that the internal pressure of the battery cell case 200 decreases.

[0031] The sealing member 224 seals the liquid injection port h formed in the cover 220. The liquid injection port h is a through hole for injecting electrolyte into the battery cell case 200 during the manufacturing process of the battery cell 1. The liquid injection port h is sealed by the sealing member 224 after the electrolyte is injected into the case body 210 through the liquid injection port h.

[0032] A pair of external terminals 300 are fixed to the battery cell housing 200. One of the pair of external terminals 300 is a positive external terminal, and the other is a negative external terminal. Each external terminal 300 is fixed to the upper surface of the cover 220 via an upper insulating portion 510 described later. Each external terminal 300 is made of a metal such as aluminum. Each external terminal 300 is formed into a rectangular parallelepiped shape, for example. A bus bar (not shown) is connected to each external terminal 300 by welding or the like.

[0033] The pair of connecting members 400 connects the plurality of collector tabs 112p, 122n and the external terminal 300. The pair of connecting members 400 includes a positive connecting portion 410 connecting the plurality of positive tabs 112p and the positive external terminal 300, and a negative connecting portion 420 connecting the plurality of negative tabs 122n and the negative external terminal 300.

[0034] The positive electrode connecting portion 410 includes a positive electrode current collecting plate 412 , a positive electrode connecting pin 414 , and an intermediate member 416 .

[0035] The positive electrode current collector plate 412 is connected to the plurality of positive electrode tabs 112p by welding or the like. The positive electrode current collector plate 412 is formed in a flat plate shape.

[0036] The positive electrode connecting pin 414 is connected to the positive electrode external terminal 300. The positive electrode connecting pin 414 is inserted into a through hole provided in the cover 220 and connected to the positive electrode external terminal 300 by welding, crimping (caulking, caulking), or the like.

[0037] The intermediate member 416 connects the positive electrode current collecting plate 412 and the positive electrode connecting pin 414 . The lower surface of the intermediate member 416 is connected to the upper surface of the positive electrode current collecting plate 412 , and the upper surface of the intermediate member 416 is connected to the lower end of the positive electrode connecting pin 414 .

[0038] The negative electrode connecting portion 420 includes a negative electrode current collecting plate 422 , a negative electrode connecting pin 424 , and an intermediate member 426 .

[0039] The negative electrode current collector plate 422 is connected to the plurality of negative electrode tabs 122n by welding or the like. The negative electrode current collector plate 422 is formed in a flat plate shape.

[0040] The negative electrode connection pin 424 is connected to the negative electrode external terminal 300. The negative electrode connection pin 424 is connected to the negative electrode external terminal 300 by welding, crimping, etc. in a state where the negative electrode connection pin 424 is inserted into a through hole provided in the cover 220.

[0041] The intermediate member 426 connects the negative electrode current collecting plate 422 and the negative electrode connecting pin 424. The lower end of the intermediate member 426 is connected to the end of the negative electrode current collecting plate 422. The upper surface of the intermediate member 426 is connected to the lower end of the negative electrode connecting pin 424.

[0042] The insulating member 500 insulates the storage battery unit case 200 from the connecting member 400 . The insulating member 500 includes an upper insulating portion 510 , a lower insulating portion 520 , an insulator 530 , and an insulating plate 540 .

[0043] The upper insulating portion 510 is fixed to the upper surface of the cover 220. The upper insulating portion 510 is disposed between the cover 220 and the external terminal 300. The upper insulating portion 510 is provided with insertion holes through which the coupling pins 414 and 424 are inserted.

[0044] The lower insulating portion 520 is fixed to the lower surface of the cover 220. The lower insulating portion 520 is disposed between the cover 220 and the upper surfaces of the intermediate members 416 and 426. The lower insulating portion 520 is provided with insertion holes through which the coupling pins 414 and 424 are inserted.

[0045] The insulator 530 is disposed between the connecting pins 414 and 424 and the cover 220. The insulator 530 is formed in a cylindrical shape and surrounds the connecting pins 414 and 424.

[0046] As described above, in the storage cell 1 of the present embodiment, the plurality of collector tabs 112p and 122n are arranged in a manner aligned in the second direction and are bent so as to overlap adjacent collector tabs, so that the storage space for the collector tabs 112p and 122n is reduced. Furthermore, the thickness adjustment portion 154 of the insulating plate 150 gradually becomes thinner as it goes to the inner side in the second direction, so that the position of the outer surface of the collector tab 112p and 122n arranged at the end in the second direction is less different from the position of the outer surface of the other collector tabs 112p and 122n.

[0047] In addition, if Figure 4 As shown, the shell body 210 may be formed into a cylindrical shape (for example, a square cylindrical shape), and the cover 220 may have a first cover portion 220a that closes the opening 210a on one side of the shell body 210 and a second cover portion 220b that closes the opening 210b on the other side of the shell body 210. In this case, the connecting member 400 may also be omitted. In other words, the plurality of positive electrode tabs 112p may be directly connected to the first cover portion 220a by welding or the like, and the plurality of negative electrode tabs 122n may be directly connected to the second cover portion 220b by welding or the like. In this case, the insulating member 500 is disposed between the shell body 210 and each of the cover portions 220a, 220b.

[0048] Those skilled in the art will appreciate that the above-described exemplary embodiments are specific examples of the following aspects.

[0049] [Solution 1]

[0050] A power storage unit comprising:

[0051] Electrode body;

[0052] an insulating plate arranged in contact with the electrode body; and

[0053] a storage unit casing, accommodating the electrode body and the insulating plate,

[0054] The electrode body has:

[0055] A plurality of electrodes are arranged in a row in one direction; and

[0056] a separator for insulating each of the plurality of electrodes;

[0057] Each of the plurality of electrodes has:

[0058] Collector foil; and

[0059] An active material layer is provided on the current collector foil,

[0060] The electrode body has:

[0061] an electrode body main body arranged such that the portions of the collector foil where the active material layer is provided are arranged in the one direction with the separator interposed therebetween; and

[0062] A plurality of collector tabs are formed at a portion of the collector foil where the active material layer is not provided, protrude from the electrode body in a first direction perpendicular to the one direction, and are arranged in a row in a second direction perpendicular to both the one direction and the first direction.

[0063] Each of the plurality of collector tabs is bent in a state where a portion of the collector tab overlaps with a collector tab adjacent to the collector tab.

[0064] The insulating plate has:

[0065] A base portion is disposed between the electrode body and the plurality of collector ears; and

[0066] a thickness adjusting portion provided at an end portion of the base portion in the second direction,

[0067] The thickness adjustment portion gradually becomes thinner as it goes toward the inner side in the second direction.

[0068] In the power storage unit, a plurality of collector tabs are arranged in a manner of being arranged in the second direction, and are bent in a state of overlapping with adjacent collector tabs, so that the space for accommodating the collector tabs is reduced. In addition, the thickness adjustment portion of the insulating plate gradually becomes thinner as it goes to the inner side in the second direction, so that the deviation between the position of the outer surface of the collector tab arranged at the end in the second direction and the position of the outer surface of the other collector tabs is reduced.

[0069] [Solution 2]

[0070] According to the power storage unit of claim 1,

[0071] The battery unit housing has:

[0072] a shell body having an opening portion protruding from the electrode body body toward the plurality of collector tabs; and

[0073] A cover is provided to close the opening of the housing body.

[0074] The plurality of collector tabs are welded to the cover.

[0075] Although the embodiments of the present invention have been described, the embodiments disclosed herein are illustrative in all aspects and are not restrictive. The scope of the present invention is indicated by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A power storage unit comprising: Electrode body; an insulating plate arranged in contact with the electrode body; and a storage unit casing, accommodating the electrode body and the insulating plate, The electrode body has: A plurality of electrodes are arranged in a row in one direction; and a separator for insulating each of the plurality of electrodes; Each of the plurality of electrodes has: Collector foil; and An active material layer is provided on the current collector foil, The electrode body has: an electrode body main body arranged such that the portions of the collector foil where the active material layer is provided are arranged in the one direction with the separator interposed therebetween; and A plurality of collector tabs are formed at a portion of the collector foil where the active material layer is not provided, protrude from the electrode body in a first direction perpendicular to the one direction, and are arranged in a row in a second direction perpendicular to both the one direction and the first direction. Each of the plurality of collector tabs is bent in a state where a portion of the collector tab overlaps with a collector tab adjacent to the collector tab. The insulating plate has: A base portion is disposed between the electrode body and the plurality of collector ears; and a thickness adjusting portion provided at an end portion of the base portion in the second direction, The thickness adjustment portion gradually becomes thinner as it goes toward the inner side in the second direction.

2. The power storage unit according to claim 1, The battery unit housing has: a shell body having an opening portion protruding from the electrode body body toward the plurality of collector tabs; and A cover is provided to close the opening of the housing body. The plurality of collector tabs are welded to the cover.

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