JP6988346B2 - Power storage device - Google Patents

Description

The present disclosure relates to a power storage device.

Conventionally, a power storage device including a plurality of battery cells has been known. The battery module described in JP-A-2014-102939 includes a plurality of battery cells, a plurality of intermediate members, and a case.

The case houses a plurality of battery cells and a plurality of intermediate members inside. The case includes a bottom plate, an end plate, and a side plate, and the battery cell is housed in a space surrounded by each plate. The battery cell includes a box-shaped storage case and an electrode body arranged in the storage case.

The intermediate member includes an insulating sheet and supports provided on both sides of the insulating sheet. Intermediate members are arranged between battery cells. The support portion provided on the intermediate member supports the central portion of the battery cell.

When accommodating the battery cells in the case, a gap is provided between the battery cells and between the battery cell and the end plate, and after arranging the battery cells, an intermediate member is arranged in each gap.

Japanese Unexamined Patent Publication No. 2014-102939

The dimensions of the battery cell vary depending on the manufacturing variation of the storage case and the manufacturing variation of the electrode body. Therefore, depending on the battery cell to be accommodated, there may be a gap between the end plate and the battery cell, between the battery cell and the intermediate member, or the intermediate member may not be inserted between the battery cells.

In such a case, it is conceivable to insert a spacer between the battery cells to fix each battery cell.

However, the size of the gap caused by the dimensional variation of the battery cell varies, and preparing various spacers according to the size of the gap leads to an increase in manufacturing cost.

The above-mentioned problems are not limited to battery modules provided with battery cells, and similar problems occur in capacitors provided with a plurality of capacitive elements.

The present disclosure has been made in view of the above-mentioned problems, and an object thereof is to provide each power storage element even if the dimensions of the power storage element vary in a power storage device provided with a plurality of power storage elements. It is an object of the present invention to provide a power storage device capable of applying a uniform load and reducing the manufacturing cost.

The power storage device according to the present disclosure includes a plurality of power storage elements arranged in one direction, a storage case accommodating the plurality of power storage elements, and at least between the power storage elements or at least at the ends of the plurality of power storage elements arranged in one direction. It is provided with a plate-shaped spacer arranged in any of them. The spacer includes a first main surface and a second main surface located at the end in the thickness direction, and a plurality of protrusions formed on the first main surface. Assuming that the two spacers are opposed to each other, each convex portion of the plurality of convex portions formed on one spacer is formed so as to be fitted between the plurality of convex portions formed on the other spacer.

In the above-mentioned power storage device, when stacking the spacers, the total thickness of the stacked spacers can be changed by changing the stacking mode. Thereby, the spacers can be inserted into the gaps of various dimensions by adjusting the stacking mode of the spacers, the number of spacers, and the like according to the dimensions of the gaps generated between the power storage elements.

According to the power storage device according to the present disclosure, even if the dimensions of the power storage element vary, it is possible to apply an even load to each power storage element and reduce the manufacturing cost.

It is an exploded perspective view which shows the power storage device 1. It is a perspective view which shows the case body 5. It is a perspective view which shows the cell unit 3. It is a perspective view which shows the spacer 21A. It is a top view which shows the spacer 21A, and is the top view which shows the main surface 35A side. It is a perspective view which shows the spacer 21A, and is the perspective view which shows the main surface 36A side. FIG. 6 is a cross-sectional view taken along the line VII-VII of FIG. FIG. 3 is a cross-sectional view taken along the line VIII-VIII of FIG. It is a side view which shows the spacer 21B and the spacer 21C. It is a side view which shows the spacer 21D and the spacer 21E. It is a side view which shows the spacer 21F, 21G, 21H. It is a side view which shows the modification of the combination mode of the spacers 21F, 21G, 21H. It is a side view which shows the spacer 100 which concerns on a comparative example.

The power storage device 1 according to the present embodiment will be described with reference to FIGS. 1 to 13. Of the configurations shown in FIGS. 1 to 13, the same or substantially the same configuration may be designated by the same reference numerals and duplicated description may be omitted.

FIG. 1 is an exploded perspective view showing a power storage device 1. The power storage device 1 includes a storage case 2 and cell units 3 and 4.

The storage case 2 includes a case body 5, a lid 6, and a plurality of bolts 7. The case body 5 is formed with an opening that opens upward. The lid 6 is provided so as to close the opening of the case body 5. A plurality of flanges 8 are formed on the outer peripheral edge of the lid 6. Each flange 8 is formed with a through hole into which a bolt 7 is inserted.

The cell units 3 and 4 include a plurality of battery cells 20, and the plurality of battery cells 20 are arranged so as to be arranged in the arrangement direction D1. The cell unit 3 and the cell unit 4 are arranged so as to be arranged in the arrangement direction D2.

FIG. 2 is a perspective view showing the case body 5. The case body 5 includes a bottom plate 10, a peripheral wall 11, a partition wall 12, and a boss 13.

The peripheral wall 11 is formed so as to rise upward from the outer peripheral edge portion of the bottom plate 10. The peripheral wall 11 includes side walls 17A and 17B and side walls 18A and 18B.

The side wall 17A and the side wall 17B are arranged so as to face each other in the arrangement direction D1. The side walls 18A and 18B are arranged so as to face each other in the arrangement direction D2.

The partition wall 12 is provided so as to divide the inside of the storage case 2 into two storage spaces 15 and 16. The partition wall 12 is formed so as to extend in the arrangement direction D1.

A plurality of bosses 13 are provided on the outer peripheral surface of the peripheral wall 11 at intervals. The boss 13 is formed with a hole into which the bolt 7 is inserted, and a female screw for screwing the threaded portion of the bolt 7 is formed in this hole.

Each bolt 7 is inserted into the flange 8 and the boss 13, and the lid 6 is fixed to the case body 5 by the plurality of bolts 7.

With reference to FIGS. 1 and 2, the cell unit 3 is housed in the storage space 15, and the cell unit 4 is housed in the storage space 16.

The cell units 3 and 4 include a plurality of battery cells 20. The plurality of battery cells 20 are provided so as to be arranged in one direction.

FIG. 3 is a perspective view showing the cell unit 3. The cell unit 3 includes a plurality of battery cells 20 and a plurality of spacers 21A, 21B, 21C, 21D, 21E.

In the example shown in FIG. 3, the cell unit 3 includes five spacers 21A, 21B, 21C, 21D, 21E.

The battery cell 20 includes a case 22 and an electrode body 23. The case 22 is made of, for example, aluminum or an aluminum alloy. The electrode body 23 includes a plurality of positive electrode sheets, a plurality of separators, and a plurality of negative electrode sheets.

The case 22 includes a case body 24 and a lid 25. The case body 24 is formed with an opening that opens upward. The lid 25 is welded to the opening edge of the case body 24.

The case body 24 is formed by squeeze molding or extrusion molding, and the dimensions of the case body 24 may vary.

Therefore, for example, when the cell unit 3 is accommodated in the accommodation space 15, a gap may occur between the side walls 17A and 17B of the case body 5 and the cell unit 3 depending on the cell unit 3.

The electrode body 23 is formed by sequentially laminating a positive electrode sheet, a separator, and a negative electrode sheet. Therefore, in the manufacturing process of the electrode body 23, the dimensional variation of the electrode body 23 is likely to occur. Further, the dimensions of the electrode body 23 vary depending on the charging state and the temperature. For example, when the charge amount of the electrode body 23 is large, the electrode body 23 is deformed to swell, and when the charge amount is small, the size of the electrode body 23 may be small.

Therefore, when the cell unit 3 is housed in the storage space 15, a gap is generated between the battery cells 20 and a gap is generated between the battery cell 20 and the side walls 17A and 17B.

When a gap is formed between the battery cells 20 or between the battery cells 20 and the side walls 17A and 17B as described above, it becomes difficult for the load applied to each battery cell 20 to be uniform.

The load applied to the battery cell 20 affects the battery capacity of the battery cell 20. If the load applied to each battery cell 20 varies, the battery capacity of each battery cell 20 is affected. As a result, as a result of repeated charging and discharging, there is a possibility that adverse effects such as lithium precipitation may occur in the specific battery cell 20.

In the power storage device 1 according to the present embodiment, the cell units 3 and 4 are appropriately arranged with spacers 21 in the cell units 3 and 4 according to the state of the cell units 3 and 4, and the cell units 3 and 4 are arranged. While adjusting the dimensions of, the gap between the battery cells 20 is filled.

As a result, the load applied to each battery cell 20 in the cell units 3 and 4 is equalized.

In the example shown in FIG. 3, the spacer 21A is inserted as a single piece between the battery cell 20A and the battery cell 20B.

Two spacers 21B and 21C are stacked and inserted between the battery cell 20C and the battery cell 20D. The spacer 21D and the spacer 21E are also inserted in layers between the battery cell 20E and the battery cell 20F. Each of the spacers 21A to 21F has the same or substantially the same shape.

FIG. 4 is a perspective view showing the spacer 21A. The spacer 21A includes a substrate 30A and a plurality of convex portions 31A1 to 31A18.

The substrate 30A is formed in a plate shape. The substrate 30A includes main surfaces 35A and 36A and a peripheral surface 37A. The main surface 35A and the main surface 36A are located at both ends in the thickness direction TH. The peripheral surface 37 is formed so as to connect the main surface 35A and the main surface 36A. The spacer 21A is arranged so that the thickness direction TH faces the arrangement direction D1.

The protrusions 31A1 to 31A9 are formed on the main surface 35A so as to be arranged in an array at intervals from each other. Each of the convex portions 31A to 31A9 is formed so as to protrude from the main surface 35A.

Each of the convex portions 31A1 to 31A9 includes an end surface located in the protruding direction of each of the convex portions 31A to 31A9, and each end surface is formed in a flat surface shape.

A groove 40A is formed between the convex portions 31A1 to 31A9 by the convex portions 31A to 31A9. The groove portion 40A is formed in a grid pattern.

In the height direction H, the length of each convex portion 31A1 to 31A9 and the length of the groove portion 40A are close to each other, and the length of the groove portion 40A is slightly longer.

In the width direction W, the length of each convex portion 31A1 to 31A9 and the length of the groove portion 40A are close to each other, and the length of the groove portion 40A is slightly longer.

FIG. 5 is a plan view showing the spacer 21A, and is a plan view showing the main surface 35A side. In the example shown in FIG. 6 and the like, when the main surface 35A of the spacer 21A is viewed in a plan view, the end faces of the convex portions 31A1 to 31A9 are formed in a square shape, and the outer peripheral edge of the main surface 35A is also formed in a square shape. It is formed. As the shape of each convex portion, various shapes such as a polygonal shape, a circular shape, and an elliptical shape can be appropriately adopted.

FIG. 6 is a perspective view showing the spacer 21A, and is a perspective view showing the main surface 36A side. A plurality of convex portions 31A11 to 31A19 are formed on the main surface 36A. The convex portions 31A11 to 31A19 are also formed so as to protrude from the main surface 36A.

The convex portions 31A11 to 31A19 are arranged in an array at intervals from each other. Each of the convex portions 31A11 to 31A19 includes an end surface located in the protruding direction of each of the convex portions 31A11 to 31A19, and each end surface is formed in a flat surface shape. A groove 41A is formed between the convex portions 31A11 to 31A19 by the convex portions 31A11 to 31A19. The groove portion 41A is also formed in a grid pattern like the groove portion 40A.

The dimensions of the convex portions 31A11 to 31A19 and the dimensions of the convex portions 31A1 to 31A9 are the same or substantially the same. Each dimension of the groove 40A and each dimension of the groove 41A are also aligned or substantially located.

FIG. 7 is a cross-sectional view taken along the line VII-VII of FIG. FIG. 8 is a cross-sectional view taken along the line VIII-VIII of FIG. First, in FIG. 7, the convex portion 31A2 and the convex portion 31A12 are formed so as to overlap each other in the thickness direction TH. It is arranged. The convex portion 31A5 and the convex portion 31A15 are formed so as to overlap each other in the thickness direction TH. Both the convex portion 31A8 and the convex portion 31A18 are formed so as to overlap each other in the thickness direction TH.

Similarly, the convex portions 31A1, 31A4, 31A7, 31A3, 31A6, 31A9 and the convex portions 31A11, 31A14, 31A17, 31A13, 31A16, 31A19 overlap each other in the thickness direction TH. That is, each convex portion 31A1 to 31A9 is formed so as to overlap each convex portion 31A11 to 31A19 in the thickness direction TH. Therefore, the groove portion 40A and the groove portion 41A are formed so as to overlap each other in the thickness direction TH.

In FIG. 7, the distance t1 from the end faces of the convex portions 31A4, 31A5, 31A6 to the end faces of the convex portions 31A14, 31A15, 31A16 in the thickness direction TH is, for example, 1.5 mm.

In the thickness direction TH, the distance t2 between the main surface 36A (bottom of the groove 41A) and the main surface 35A (bottom of the groove 40A) is, for example, 0.5 mm.

In the present embodiment, the spacer 21A is arranged between the battery cell 20A and the battery cell 20B, and the battery cell 20A and the battery cell 20B are separated by the spacer 21A by about 1.5 mm. There is.

Although the configuration of the spacer 21A has been described in detail, the spacers 21B, 21C, 21D, and 21E also have the same shape or substantially the same shape as the spacer 21A.

Assuming that two spacers 21A are prepared in the spacer 21A formed as described above, one convex portion 31A1 to 31A9 and the convex portion 31A11 to the convex portion 31A19 are fitted into the groove portions 40A and 41A of the other spacer 21A. Can be included.

Thereby, the spacers can be inserted into various gaps depending on how the plurality of spacers are combined, and the details thereof will be described with reference to spacers 21C, 21D, spacers 21E, 21F and the like. FIG. 9 is a side view showing the spacer 21B and the spacer 21C. The spacer 21B and the spacer 21C are arranged so that the convex portions are in contact with each other.

In FIG. 9, the convex portion 31A17 of the spacer 21B and the convex portion 31C7 of the spacer 21C are in contact with each other. Similarly, the convex portions 31B18 and 31B19 are in contact with the convex portions 31C8 and 31C9. The other convex portion of the spacer 21B (not shown) is in contact with the convex portion of the spacer 21C.

Therefore, in the state where the spacer 21B and the spacer 21C are overlapped, the total thickness t3 of the spacer 21B and the spacer 21C in the thickness direction TH is 3.0 mm.

FIG. 10 is a side view showing the spacer 21D and the spacer 21E.
The convex portions 31D18 and 31D19 of the spacer 21D are fitted into the groove portion 40E of the spacer 21E. It should be noted that other convex portions adjacent to the convex portions 31D17 and 31D18 in the width direction W are also fitted in the groove portion 40E.

The convex portions 31E8 and 31E9 of the spacer 21E are fitted into the groove portion 41D of the spacer 21D. It should be noted that other convex portions adjacent to the convex portions 31E and 31E9 in the width direction W are also fitted in the groove portion 41D.

Therefore, in the state where the spacer 21D and the spacer 21E are overlapped, the total thickness t4 of the spacer 21D and the spacer 21E in the thickness direction TH is 2.5 mm.

As shown in FIGS. 9 and 10, it can be seen that the thickness of the combined spacers can be adjusted depending on the combination mode even if the two spacers have the same shape.

Next, it will be described that the three spacers can be combined to have various thicknesses by using FIGS. 11 to 13.

FIG. 11 is a side view showing the spacers 21F, 21G, and 21H. In the combination mode shown in FIG. 11, the convex portions 31F17, 31F18, 31F19 of the spacer 21F are in contact with the convex portions 31G7, 31G8, 31G9 of the spacer 21G.

The convex portions 31G17, 31G18, 31G19 of the spacer 21G are in contact with the convex portions 31G7, 31G8, 31G9 of the spacer 21H.

As described above, the thickness t5 in the width direction W when the spacers 21F, 21G, and 21H are combined is 4.5 mm.

FIG. 12 is a side view showing a modified example of the combination mode of the spacers 21F, 21G, and 21H. In the example shown in FIG. 12, the convex portions 31F17 and 31F18 of the spacer 21F are fitted into the groove portions 40G of the spacer 21G.

The convex portions 31G8 and 31G9 of the spacer 21G are fitted into the groove portion 41F of the spacer 21F.

The convex portions 31G18 and 31G19 of the spacer 21G are fitted in the groove portion 40H of the spacer 21H. The convex portions 31H7 and 31H8 of the spacer 21H are fitted in the groove portion 41G.

The total thickness t6 of the spacers 21F, 21G, and 21H in the combination mode shown in FIG. 12 is about 3.5 mm.

As shown in FIGS. 11 and 12, the total thickness of the spacers can be adjusted in the three spacers 21F, 21G, and 21H depending on the combination mode.

FIG. 13 is a side view showing the spacer 100 according to the comparative example. In this spacer 100, even if two spacers 100 are used, the total thickness of the spacers can be formed in only one kind. Similarly, even if three spacers 100 are used, only one thickness can be formed.

On the other hand, the size of the gap generated between the battery cells 20 and the size of the gap generated between the battery cells 20 and the side walls 17A and 17B are various.

Therefore, if the spacer 100 is to be inserted into the gap between the cell units 3 and 4, it becomes necessary to prepare various spacers 100 having different thicknesses.

On the other hand, according to the spacer 21A according to the present embodiment, even if the gaps have various gap dimensions of the cell units 3 and 4, the number of spacers 21A and the combination mode are different, so that the cell units 3 and 3 are combined. It can be inserted into the gap of 4. Therefore, it is less necessary to prepare a plurality of types of spacers having different thicknesses, and the manufacturing cost can be reduced. In the above embodiment, in the two spacers in which the convex portion and the groove portion are formed, each spacer is formed so that the convex portion fits into the groove portion. On the other hand, the portion into which each convex portion fits is not limited to a shape such as a groove portion, and may be, for example, a concave portion, a dent portion, or a concave portion, and various shapes may be used as the shape into which the convex portion fits. Can be adopted. That is, the convex portion of each spacer is formed so as to be fitted between the convex portions of the other spacers.

Although each embodiment based on the present invention has been described above, the matters disclosed this time are examples in all respects and are not limiting. The technical scope of the present invention is indicated by the scope of claims and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 power storage device, 2 storage cases, 3,4 cell units, 5,24 case bodies, 6,25 lids, 7 bolts, 8 flanges, 10 bottom plates, 11 peripheral walls, 12 partition walls, 13 bosses, 15,16 storage spaces, 17A, 17B, 18A, 18B side wall, 20, 20A, 20B, 20C, 20D, 20E, 20F battery cell 21,21A, 21B, 21C, 21D, 21E, 21F, 21G, 21H, 100 spacer, 22 cases, 23 Electrode body, 30A substrate, 31A1 to 31A9, 31A11 to 31A19 convex part, 35A, 36A main surface, 37,37A peripheral surface, 40A, 41A groove part, D1, D2 arrangement direction, H height direction, TH thickness direction, W Width direction, t1, t2 distance, t3, t5, t6 thickness.

Claims (2)

Multiple power storage elements arranged in one direction,
A plate-shaped spacer arranged between the power storage elements or at least one of the ends of the plurality of power storage elements arranged in one direction.
Equipped with
The spacer includes a first main surface and a second main surface located at the end in the thickness direction, a plurality of first convex portions formed so as to be arranged in an array on the first main surface, and the first convex portion. 2 Containing a plurality of second protrusions formed so as to be arranged in an array on the main surface.
A lattice-shaped first groove portion is formed between the plurality of first convex portions.
A lattice-shaped second groove portion is formed between the plurality of second convex portions.
The plurality of first convex portions and the plurality of second convex portions are formed so as to overlap each other in the thickness direction of the spacer.
The first groove portion and the second groove portion are formed so as to overlap each other in the thickness direction of the spacer.
When two of the spacer and are opposed, the first convex portion of the plurality which are formed on one of the spacer, formed as put fits into the first groove or the second groove portion formed on the other of the spacer The power storage device. With a plurality of the spacers
The plurality of spacers include a first spacer, a second spacer, and a third spacer.
In the first spacer, the second spacer, and the third spacer, the plurality of first convex portions of the first spacer are fitted into the second groove portion of the second spacer, and the second spacer is used. The plurality of second convex portions of the first spacer are fitted into the first groove portion of the first spacer, and the plurality of first convex portions of the second spacer are fitted into the second groove portion of the third spacer. The power storage device according to claim 1, wherein the plurality of second convex portions of the third spacer are arranged in a state of being fitted into the first groove portion of the second spacer.

Images