CN112136240B

CN112136240B - Battery cell

Info

Publication number: CN112136240B
Application number: CN201980031979.XA
Authority: CN
Inventors: 岩田直之
Original assignee: Aesc Japan
Current assignee: Envision AESC Japan Ltd
Priority date: 2018-05-16
Filing date: 2019-04-25
Publication date: 2024-05-07
Anticipated expiration: 2039-04-25
Also published as: JP6964190B2; WO2019220921A1; JPWO2019220921A1; CN112136240A

Abstract

The outer package (200) is folded back from the 1st surface (102 a) to the 2 nd surface (102 b) of the laminate (100) via the 4 th side surface (104 d). The outer package (200) has a 1st portion (210) and a2 nd portion (220). The 1st part (210) and the 2 nd part (220) are bonded to the outer sides of the 1st side (104 a) and the 2 nd side (104 b) of the laminate (100). The 1st part (210) and the 2 nd part (220) of the outer member (200) have deformations (202 a) (1 st deformation). The deformation (202 a) extends from the 1st corner (106 a) of the laminate (100).

Description

Battery cell

Technical Field

The present invention relates to a battery.

Background

In recent years, nonaqueous electrolyte secondary batteries, particularly lithium ion secondary batteries, have been developed. The lithium ion secondary battery has a laminate including a positive electrode, a negative electrode, and a separator. The positive electrode, the negative electrode, and the separator are laminated such that the positive electrode and the negative electrode are separated by the separator. The laminate is sealed by an outer package.

Patent document 1 describes an example of a method of sealing a laminate by an exterior material. In this example, the outer member comprises 2 separable membranes. Each film has a recess. The 2 films are bonded to each other so that the laminate is accommodated in a space formed by the concave portions of the respective films. Patent document 1 describes forming wrinkles in an exterior material around a laminate.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 2006-185713

Disclosure of Invention

Problems to be solved by the invention

The method of sealing the laminate by the exterior material is not limited to the example described in patent document 1, but includes a method different from the example described in patent document 1, for example, a method of folding back the exterior material along the laminate. The present inventors have studied to fold back an exterior material along a laminate, and particularly studied to reduce a storage space of a laminate formed of the exterior material.

The invention aims to reduce the storage space of a laminate formed by an exterior member.

Means for solving the problems

According to the present invention, there is provided a battery comprising: a laminate including a1 st electrode, a 2 nd electrode, and a separator, the laminate including a1 st surface, a 2 nd surface opposite to the 1 st surface, a1 st side surface between the 1 st surface and the 2 nd surface and having a1 st lead formed thereon, a 2 nd side surface intersecting the 1 st side surface, a3 rd side surface opposite to the 1 st side surface, a4 st side surface opposite to the 2 nd side surface, and a1 st angle between the 1 st side surface and the 2 nd side surface; and an exterior material folded back from the 1 st face of the laminate to the 2 nd face via the 4 th side face, the exterior material having a1 st part and a 2 nd part bonded to the outside of the 1 st side face and the 2 nd side face of the laminate, the 1 st part and the 2 nd part of the exterior material having a1 st deformation extending from the 1 st corner of the laminate.

Effects of the invention

According to the present invention, the storage space of the laminate formed by the exterior material can be reduced.

Drawings

The above objects, as well as other objects, features and advantages will be further apparent from the following description of the preferred embodiments and the accompanying drawings.

Fig. 1 is a perspective view of a battery according to an embodiment.

Fig. 2 is an enlarged plan view of a portion of the battery shown in fig. 1.

Fig. 3 is a diagram for explaining an example of the method for manufacturing the battery shown in fig. 1 and 2.

Fig. 4 is a diagram for explaining an example of a method for manufacturing the battery shown in fig. 1 and 2.

Fig. 5 is a diagram for explaining an example of the method for manufacturing the battery shown in fig. 1 and 2.

Fig. 6 is a diagram for explaining an example of the method for manufacturing the battery shown in fig. 1 and 2.

Fig. 7 is a diagram for explaining an example of the method for manufacturing the battery shown in fig. 1 and 2.

Fig. 8 is a diagram showing a modification of fig. 2.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and description thereof is omitted as appropriate.

Fig. 1 is a perspective view of a battery 10 according to an embodiment. Fig. 2 is an enlarged plan view of a part of the battery 10 shown in fig. 1.

The outline of the battery 10 will be described with reference to fig. 1. The battery 10 includes a laminate 100 and an exterior member 200. The laminate 100 includes a1 st electrode 110, a 2 nd electrode 120, and a separator 130. The laminate 100 has a1 st surface 102a, a 2 nd surface 102b, a1 st side surface 104a, a 2 nd side surface 104b, a 3 rd side surface 104c, a 4 th side surface 104d, and a1 st corner 106a. The 2 nd face 102b is located on the opposite side of the 1 st face 102 a. The 1 st side 104a is located between the 1 st and 2 nd sides 102a, 102b. The 1 st lead 112 is formed on the 1 st side 104 a. The 2 nd side 104b intersects the 1 st side 104 a. Side 3, 104c, is on the opposite side of side 1, 104 a. The 4 th side 104d is located on the opposite side of the 2 nd side 104 b. Angle 1a is located between side 1 and side 2, 104a and 104 b. The outer package 200 is folded back from the 1 st surface 102a to the 2 nd surface 102b of the laminate 100 via the 4 th side surface 104 d. The outer member 200 has a1 st portion 210 and a 2 nd portion 220. The 1 st and 2 nd portions 210 and 220 are bonded to the outer sides of the 1 st and 2 nd side surfaces 104a and 104b of the laminate 100. The 1 st portion 210 and the 2 nd portion 220 of the outer member 200 have deformations 202a (1 st deformation). The deformation 202a extends from the 1 st corner 106a of the stack 100.

According to the above configuration, the storage space of the laminate 100 formed by the exterior material 200 can be reduced. Specifically, in the above-described structure, the 1 st portion 210 and the 2 nd portion 220 of the exterior member 200 have the deformation 202a. When the 1 st part 210 and the 2 nd part 220 of the exterior material 200 are bonded to each other in a region near the 2 nd side 104b of the laminate 100, the 1 st part 210 and the 2 nd part 220 of the exterior material 200 are deformed so that the ridge 204a (for example, fig. 5) described later is eliminated, thereby forming the deformed 202a. Thus, the presence of the deformation 202a represents: the 1 st part 210 and the 2 nd part 220 of the exterior material 200 are bonded to each other in a region near the 2 nd side 104b of the laminate 100, that is, the storage space of the laminate 100 formed by the exterior material 200 is reduced.

In the example shown in fig. 1, the 2 nd lead 122 is formed on the 3 rd side 104c of the laminate 100. The laminate 100 has a2 nd corner 106b. Angle 2b is located between side 3 104c and side 2 104 b. The 1 st portion 210 and the 2 nd portion 220 of the exterior member 200 are bonded to the outer side of the 3 rd side 104c of the laminate 100. The 1 st portion 210 and the 2 nd portion 220 of the outer member 200 have deformations 202b (2 nd deformations). The deformation 202b extends from the 2 nd corner 106b of the stack 100.

In another example, the 1 st lead 112 and the 2 nd lead 122 may be formed on a common surface of the laminate 100, for example, the 1 st side 104a or the 3 rd side 104c. When the 1 st lead 112 and the 2 nd lead 122 are both formed on the 1 st side surface 104a, the 1 st portion 210 and the 2 nd portion 220 are bonded to the outer sides of the 1 st side surface 104a and the 2 nd side surface 104b of the laminate 100, and have the deformation 202a.

The laminate 100 will be described in detail with reference to fig. 1.

The laminate 100 includes a1 st electrode 110, a2 nd electrode 120, and a separator 130. The 1 st electrode 110 and the 2 nd electrode 120 have polarities different from each other, and may be a positive electrode and a negative electrode, respectively, or may be a negative electrode and a positive electrode, respectively. The 1 st electrode 110, the 2 nd electrode 120, and the separator 130 are laminated from the 1 st face 102a to the 2 nd face 102b such that the 1 st electrode 110 and the 2 nd electrode 120 are separated by the separator 130. The laminate 100 may include a plurality of 1 st electrodes 110 and a plurality of 2 nd electrodes 120. In this case, the adjacent 1 st electrode 110 and 2 nd electrode 120 are separated by the separator 130.

The laminate 100 has a substantially rectangular parallelepiped shape. The laminate 100 has a thickness between the 1 st surface 102a and the 2 nd surface 102b, a length between the 1 st side surface 104a and the 3 rd side surface 104c, and a width between the 2 nd side surface 104b and the 4 th side surface 104 d.

In the example shown in fig. 1, the length of the laminate 100 (between the 1 st side 104a and the 3 rd side 104 c) is greater than the width of the laminate 100 (between the 2 nd side 104b and the 4 th side 104 d). If the ratio of the length to the width is large, the laminate 100 is easily placed such that the 2 nd side 104b or the 4 th side 104d of the laminate 100 faces downward. In order to stably mount the laminated body 100 with the 2 nd side 104b or the 4 th side 104d of the laminated body 100 facing downward, the above ratio may be set to more than 2.0, for example.

The 1 st lead 112 protrudes from the 1 st side 104a of the laminate 100. The 1 st lead 112 is electrically connected to the 1 st electrode 110 of the laminate 100.

The 2 nd lead 122 protrudes from the 2 nd side 104b of the laminate 100. The 2 nd lead 122 is electrically connected to the 2 nd electrode 120 of the laminate 100.

As will be described later, this embodiment is particularly useful when the thickness between the 1 st surface 102a and the 2 nd surface 102b is large. The laminate 100 may have a thickness of, for example, 5.0mm or more, 7.5mm or more, or 10.0mm or more between the 1 st surface 102a and the 2 nd surface 102 b.

The exterior 200 will be described in detail with reference to fig. 1.

The exterior material 200 divides a space for accommodating the laminate 100. In this space of the exterior material 200, the laminate 100 and the electrolyte are stored. In this way, the exterior member 200 seals the laminate 100.

In the example shown in fig. 1, the accommodating space of the laminate 100 formed by the exterior material 200 is not formed by the molding (emboss). The exterior material 200 is folded along the angle between the 1 st surface 102a and the 4 th side surface 104d and the angle between the 2 nd surface 102b and the 4 th side surface 104d of the laminate 100 to wrap the laminate 100. Further, the exterior material 200 includes a portion extending along the 4 th side 104d of the laminate 100. In general, molding for forming a recess having a large depth requires a complicated technique. Therefore, the greater the thickness of the laminate 100, the more complicated the technique is required to form the accommodating space of the laminate 100 formed by the exterior material 200 by press molding. In contrast, in the present embodiment, no molding is required. Therefore, even if the thickness of the laminate 100 is large, the storage space of the laminate 100 formed by the exterior material 200 can be easily formed.

The details of the deformation 202a of the exterior 200 will be described with reference to fig. 1 and 2.

The deformations 202a extend from the 1 st corner 106a of the stack 100 to the edge of the outer cover 200 (along the edge of the 1 st side 104a of the stack 100). In the cross section of the exterior member 200, the 1 st portion 210 and the 2 nd portion 220 of the exterior member 200 in the deformation 202a are curved in a convex shape. The deformation 202b also has the same shape as the deformation 202 a.

Fig. 3 to 7 are diagrams for explaining an example of a method for manufacturing the battery 10 shown in fig. 1 and 2.

First, as shown in fig. 3, the exterior material 200 is folded back from the 1 st surface 102a (fig. 1) to the 2 nd surface 102b (fig. 1) of the laminate 100 via the 4 th side surface 104 d. In this way, the 1 st part 210 and the 2 nd part 220 of the exterior material 200 are overlapped outside the 1 st side 104a, the 2 nd side 104b, and the 3 rd side 104c of the laminate 100.

Next, as shown in fig. 4, the 1 st portion 210 and the 2 nd portion 220 of the exterior material 200 are bonded to each other in the 1 st region 232. Region 1 232 is along side 1 of stack 100 at 104a.

The bump 204a (1 st bump) is formed in the 1 st portion 210 by the bonding of the 1 st portion 210 and the 2 nd portion 220 in the 1 st region 232. The ridge 204a extends from the 1 st corner 106a to the 1 st region 232. The width of the ridge 204a is narrower the farther from the 1 st corner 106 a. The bulge 204a is due to deformation occurring in the exterior member 200 by narrowing the interval between the 1 st part 210 and the 2 nd part 220 from the 1 st corner 106a of the laminate 100 to the 1 st region 232 of the exterior member 200.

By bonding the 1 st part 210 and the 2 nd part 220 in the 1 st region 232, a ridge is formed on the 2 nd part 220 on the opposite side of the ridge 204a in the same manner as the ridge 204a of the 1 st part 210.

As shown in fig. 4, the 1 st portion 210 and the 2 nd portion 220 of the outer member 200 are bonded in the 3 rd region 236. Region 3 rd 236 is along side 3 rd 104c of stack 100. Thus, similarly to the ridge 204a of the 1 st part 210, the ridge 204b (2 nd ridge) is formed in the 1 st part 210. The ridge 204b extends from the 2 nd corner 106b to the 3 rd region 236. The width of the ridge 204b is narrower the farther from the 2 nd corner 106 b.

By bonding the 1 st part 210 and the 2 nd part 220 in the 3 rd region 236, a ridge is formed on the 2 nd part 220 on the opposite side of the ridge 204b in the same manner as the ridge 204b of the 1 st part 210.

Next, as shown in fig. 5, the exterior material 200 is bent along the 2 nd side 104b of the laminate 100. The single-dot chain line in fig. 5 shows a line along the bending line of the exterior member 200. By bending the outer material 200, the ridges 204a and 204b can be brought closer to the laminate 100. The reason for bending the exterior member 200 will be described later.

Next, as shown in fig. 6, the 1 st and 2 nd portions 210 and 220 of the exterior material 200 are bonded to the 1 st and 2 nd partial regions 234a and 234 b. The 1 st partial region 234a is located on the opposite side of the 1 st corner 106a from the 2 nd side 104b of the stack 100. The 2 nd partial region 234b is located on the opposite side of the 2 nd corner 106b from the 2 nd side 104b of the stack 100. The reason for bonding the 1 st and 2 nd portions 210 and 220 to the 1 st and 2 nd partial regions 234a and 234b will be described later.

Next, as shown in fig. 7, the 1 st portion 210 and the 2 nd portion 220 of the exterior material 200 are bonded to each other in the 2 nd region 234. The 2 nd region 234 is along the 2 nd side 104b of the stack 100. In the step shown in fig. 7, the pressure in the storage space of the laminate 100 formed by the exterior material 200 is reduced to be lower than the atmospheric pressure, and for example, the 1 st part 210 and the 2 nd part 220 are bonded while being reduced in pressure to be a vacuum. The 2 nd region 234 may overlap with the 1 st partial region 234a and the 2 nd partial region 234b, or may not overlap.

Next, the outer portion of the 2 nd region 234 in the outer member 200 is removed.

Thus, the battery 10 is manufactured.

In the method shown in fig. 3 to 7, the 1 st part 210 and the 2 nd part 220 of the 1 st region 232, the 2 nd region 234, and the 3 rd region 236 can be bonded by welding the 1 st part 210 and the 2 nd part 220, for example.

According to the methods shown in fig. 3 to 7, the laminated body 100 can be sealed with high reliability. Specifically, in this method, as shown in fig. 6, the 1 st part 210 and the 2 nd part 220 of the exterior material 200 are bonded to each other in the 1 st partial region 234 a. Thus, during the depressurization of fig. 7, the ridge 204a can be prevented from expanding to the 2 nd region 234. In other words, the bonding of the 1 st part 210 and the 2 nd part 220 in the 1 st part region 234a functions as a stopper for restricting the expansion of the ridge 204a. If the ridge 204a extends to the 2 nd region 234, a wrinkle (for example, a wrinkle 206 shown in fig. 8 described later) is formed on the surface of the exterior material 200 because the ridge 204a located in the 2 nd region 234 is pressed during the bonding of the 1 st portion 210 and the 2 nd portion 220 in the 2 nd region 234. Such wrinkles form leakage paths from the storage space of the laminate 100 formed by the exterior material 200 to the space outside the exterior material 200. In contrast, in the examples shown in fig. 6 and 7, such wrinkles can be suppressed. Therefore, the laminated body 100 can be sealed with high reliability.

According to the method shown in fig. 3 to 7, deformations 202a (deformations 202 b) are formed in the 1 st portion 210 and the 2 nd portion 220 of the outer package 200. Specifically, in this method, as described above, the bump 204a does not extend to the 2 nd region 234. However, if the 1 st and 2 nd portions 210 and 220 are attached to the 2 nd region 234 such that the bump 204a is planarized, the deformation 202a is formed so as to eliminate the bump 204 a. The deformation 202a itself cannot form a leak path from the storage space of the laminate 100 formed by the exterior material 200 to the space outside the exterior material 200. Therefore, the laminated body 100 can be sealed with high reliability.

According to the method shown in fig. 3 to 7, the storage space of the laminate 100 formed by the exterior material 200 can be reduced. Specifically, in this method, as shown in fig. 5, the exterior material 200 is bent along the 2 nd side 104b of the laminate 100, so that the bumps 204a and 204b approach the laminate 100. In order to suppress wrinkles in the 2 nd region 234, it is necessary that the ridges 204a and 204b do not overlap with the 2 nd region 234, the 1 st partial region 234a, and the 2 nd partial region 234 b. Accordingly, the closer the ridges 204a and 204b are to the 2 nd side 104b of the stack 100, the closer the 2 nd region 234 can be to the 2 nd side 104b of the stack 100. Therefore, the storage space of the laminate 100 formed by the exterior material 200 can be reduced.

Other examples of the method may not include the steps shown in fig. 5. In this example, the process shown in fig. 6 is performed without the process shown in fig. 5 after the process shown in fig. 4 is performed. In this example, wrinkles in the 2 nd region 234 can also be suppressed by making the ridges 204a and 204b not overlap with the 1 st and 2 nd partial regions 234a and 234b, respectively.

Fig. 8 is a diagram showing a modification of fig. 2. The battery 10 according to the modification is the same as the battery 10 according to the embodiment except for the following.

In the example shown in fig. 8, the battery 10 is manufactured without going through the process shown in fig. 6. In the example shown in fig. 8, the outer member 200 includes a fold 206. As described using fig. 3 to 7, the wrinkle 206 is formed by bonding the 1 st and 2 nd portions 210 and 220 to each other in the 2 nd region 234 in a state where the ridge 204a is expanded to the 2 nd region 234.

In the example shown in fig. 8, a deformation 202a is also formed. Even if the 1 st part 210 and the 2 nd part 220 are not bonded to the 1 st partial region 234a shown in fig. 6, the 1 st part 210 and the 2 nd part 220 of the exterior material 200 are bonded to the region near the 2 nd side 104b of the laminate 100, whereby the deformation 202a is formed so that a part of the ridge 204a is eliminated.

In the example shown in fig. 8, the storage space of the laminate 100 formed by the exterior material 200 can also be reduced.

The embodiments of the present invention have been described above with reference to the drawings, but these are examples of the present invention, and various configurations other than the above can be adopted.

The present application claims priority based on japanese patent application No. 2018-094690, filed on 5 months and 16 days, and the disclosure thereof is entirely incorporated herein.

Claims

1. A battery, comprising:

a laminate including a1 st electrode, a2 nd electrode, and a separator, the laminate including a1 st surface, a2 nd surface opposite to the 1 st surface, a1 st side surface between the 1 st surface and the 2 nd surface and having a1 st lead formed thereon, a2 nd side surface intersecting the 1 st side surface, a3 rd side surface opposite to the 1 st side surface, a4 st side surface opposite to the 2 nd side surface, and a1 st angle between the 1 st side surface and the 2 nd side surface; and

An exterior material folded back from the 1 st surface to the 2 nd surface of the laminate via the 4 th side surface, having a1 st part and a 2 nd part bonded to the outer sides of the 1 st and 2 nd side surfaces of the laminate,

The exterior material has a 1 st region where the 1 st portion and the 2 nd portion are bonded to each other along the 1 st side of the laminate, and a 2 nd region where the 1 st portion and the 2 nd portion are bonded to each other along the 2 nd side of the laminate,

The 1 st and 2 nd portions of the outer cover have 1 st ridges extending from the 1 st corner to the 2 nd region of the laminate, and 1 st deformations formed in the 1 st region extending from the 1 st ridges.

2. The battery of claim 1, wherein the battery comprises a plurality of cells,

A2 nd lead is formed on the 3 rd side surface of the laminate,

The laminate has an angle 2 between the 3 rd side and the 2 nd side,

The 1 st part and the 2 nd part of the exterior member are bonded to the outside of the 3 rd side face of the laminate,

The outer member further has a 3 rd region where the 1 st portion and the 2 nd portion are attached to each other along the 3 rd side,

The 1 st and 2 nd portions of the outer cover further have a2 nd ridge extending from the 2 nd corner of the laminate to the 2 nd region, and a2 nd deformation extending from the 2 nd ridge to form the 3 rd region.

3. The battery of claim 1, wherein the battery comprises a plurality of cells,

The laminate has a thickness of 5.0mm or more between the 1 st and 2 nd surfaces.