阅读说明：本技术 电池单体 (Battery monomer ) 是由 谷内拓哉 大田正弘 有贺稔之 于 2021-05-18 设计创作，主要内容包括：鉴于将电池单体进行模块化时的问题,本发明的目的在于,能够在前述电池单体彼此不相互发生位置偏移的情况下,高效率地将前述电池单体层叠。电池单体2,具备电池、及收容电池的外包装体,其中,从前述电池的端面,沿与前述端面垂直的方向延长设置有集电极耳引线,前述外包装体,具有从前述电池的未延长设置前述集电极耳引线的侧面,沿与前述侧面成水平的方向伸出的部分,并且,在将前述电池单体层叠而组成模块时,前述电池单体2的前述外包装体中的从前述电池的未延长设置前述集电极耳引线的侧面伸出的伸出部22c,被接合在邻接的电池单体的未延长设置集电极耳引线的侧面22a上。(In view of the problem when the battery cells are modularized, the present invention aims to efficiently stack the battery cells without causing positional deviation between the battery cells. The battery cell 2 includes a battery and an outer package for housing the battery, wherein a current collecting tab lead is extended from an end surface of the battery in a direction perpendicular to the end surface, the outer package has a portion extended from a side surface of the battery where the current collecting tab lead is not extended in a direction horizontal to the side surface, and when the battery cells are stacked to form a module, an extended portion 22c of the outer package of the battery cell 2, which is extended from the side surface of the battery where the current collecting tab lead is not extended, is joined to a side surface 22a of an adjacent battery cell where the current collecting tab lead is not extended.)

1. A battery cell comprising a battery and an exterior body for housing the battery,

a current collecting tab lead is extended from the end face of the battery along the direction vertical to the end face,

the outer package body has a portion extending from a side surface of the battery, on which the current collecting tab lead is not extended, in a direction horizontal to the side surface,

when the battery cells are stacked to form a module, the portion of the outer package of the battery cell protruding from the side surface of the battery is joined to the side surface of the adjacent battery cell.

2. The battery cell according to claim 1, wherein a portion of the exterior body that protrudes from the side surface has the same shape and size as the side surface of the adjacent battery cell.

3. The battery cell according to claim 1, wherein, when the battery cells are stacked to form a module, the portions of the exterior body that protrude from the side surfaces and the portions that are joined to the side surfaces of the adjacent battery cells are alternately arranged in the vertical direction of the battery cells stacked in the horizontal direction.

4. The battery cell according to claim 1, wherein the exterior body is formed of a single sheet of film having a portion protruding from the side surface.

5. The battery cell according to claim 1, wherein the battery is an all-solid battery cell including a laminate using a solid electrolyte.

Technical Field

The present invention relates to a battery cell, and more particularly, to a battery cell sealed by an outer package.

Background

In recent years, the spread of various sizes of electric and electronic devices such as automobiles, personal computers, and cellular phones has rapidly increased the demand for high-capacity and high-output battery elements. Examples of such a battery element include a liquid battery cell using an organic electrolytic solution as an electrolyte between a positive electrode and a negative electrode, and a solid battery cell using a flame-retardant solid electrolyte instead of the electrolyte of the organic electrolytic solution.

As such a battery element, a laminated monomer type battery cell is known in which a battery is enclosed in a laminate film (outer package) and sealed in a plate shape. In applications such as EV (Electric Vehicle) and HEV (Hybrid Electric Vehicle), a battery cell assembly is used in which a plurality of such stacked cell-type battery cells are housed in a case side by side. The battery can be prevented from entering the atmosphere by wrapping the battery with an outer package (for example, patent document 1). In the present specification, a "battery" is a member formed by a laminate of battery elements including positive and negative electrodes and an electrolyte, and a current collecting tab lead, and an article in which the battery is enclosed and sealed by a laminate film (outer package) is referred to as a "battery cell".

In order to maintain the sealing property of the laminate film (exterior body) and effectively improve the volumetric energy density of the battery module, a battery cell is disclosed which includes an exterior body in which one film is folded back so as to accommodate a battery (patent document 2). According to patent document 2, the battery cell can effectively increase the volumetric energy density of the battery module while maintaining the sealing property of the exterior body.

[ Prior art documents ]

(patent document)

Patent document 1: japanese patent laid-open No. 2012 and 16904

Patent document 2: WO2019/188825

Disclosure of Invention

[ problems to be solved by the invention ]

When the battery cells are formed into a module, it is difficult to efficiently stack the battery cells without causing positional displacement between the battery cells. If a positional deviation occurs in the lamination of the battery cells, a uniform surface pressure (restraining force) cannot be applied to the battery cells, and the battery cells may be locally damaged by an excessive load.

In view of the foregoing problems of modularization of the battery cells, an object of the present invention is to enable the battery cells to be efficiently stacked without causing positional displacement of the battery cells from each other.

[ means for solving problems ]

In order to solve the above problem, a battery cell according to the present invention includes a battery and an exterior body housing the battery, and is characterized in that: and an outer package body having a portion extending in a direction horizontal to the side surface from a side surface of the battery on which the current collecting tab lead is not extended, wherein the portion of the outer package body of the battery cell extending from the side surface of the battery is welded to the side surface of an adjacent battery cell when the battery cells are stacked to form a module.

The outer package has a portion protruding from a side surface of the battery where the current collecting tab lead is not extended, and when the battery cells are stacked to form a module, the portion protruding from the side surface where the current collecting tab lead is not extended of the outer package is welded to a side surface of an adjacent battery cell, whereby positional relationships between the battery cells are fixed to each other when the battery cells are stacked, and positional deviation due to sliding does not occur. Therefore, the battery is not damaged by a local excessive load due to the positional deviation.

Further, in the present invention, in this case, the following features: the outer package body has a portion protruding from the side surface, the portion having the same shape and size as the side surface of the adjacent battery cell.

Since the portion of the exterior body protruding from the side surface has the same shape and size as those of the side surface of the adjacent battery cell, the side surface of the battery cell is not provided with irregularities (step) due to the portion protruding from the side surface of the adjacent battery cell, and damage to the battery contained therein due to the irregularities can be avoided. Further, the portion of the exterior body protruding from the side surface is exposed from the side surface of the adjacent battery cell, and adverse effects on the adjacent battery cell can be further avoided.

Further, in the present invention, in this case, the following features: when the battery cells are stacked to form a module, the welded portions between the portions extending from the side surfaces and the side surfaces of the adjacent battery cells are alternately arranged in the vertical direction of the horizontally stacked battery cells.

The side surface opposite to the welded portion is covered with two films when the battery is packed with the films of the exterior body covering the battery. The side surface on the welded portion side is covered with two films including the film of the portion protruding from the adjacent battery cell. Then, the side surfaces of all the cells of the stacked battery cells are protected by the two sheets of films.

Further, in the present invention, in this case, the following features: the outer package body is formed of a single film having a portion extending from the side surface.

By forming the outer package from one sheet of film, the number of bonding sites during packaging can be minimized, and the sealing properties can be improved. Further, since the one film (the outer package) has a portion protruding from the side surface on which the current collecting tab lead is not provided in an extended state, the portion protruding from the side surface of the battery cell is naturally generated when the battery is packaged with the one film covering the battery, and thus the manufacturing efficiency can be improved.

Further, in the present invention, in this case, the following features: the battery is an all-solid-state battery cell composed of a laminate using a solid electrolyte.

The all-solid battery cell is fragile and easily broken. Therefore, when the battery cells of the present invention are stacked, the following structure is effective particularly when applied to all-solid battery cells, that is: the battery is prevented from being damaged by a local excessive load caused by the positional deviation so that the positional relationship between the battery cells is fixed to each other without causing the positional deviation.

[ Effect of the invention ]

As described above, in the present invention, when the battery cells are stacked for modularization, the positional relationship between the battery cells is fixed without causing positional deviation. Therefore, since the uniform surface pressure (restraining force) can be applied to the battery cells, damage to the battery due to a local excessive load caused by positional displacement can be avoided.

Drawings

Fig. 1 is a perspective view of a battery in a battery cell of the present invention.

Fig. 2 is a perspective view showing an external appearance of a battery cell according to the present invention.

Fig. 3 is a developed view of the outer package for battery cells of the present invention.

Fig. 4 is a cross-sectional view of a stacked battery cell of the present invention.

Detailed Description

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

In the embodiment, the battery 1 of the present invention is an all-solid battery, and has a rectangular parallelepiped shape as shown in fig. 1, and has six surfaces of a top surface 11a, a bottom surface 11b, side surfaces 12a,12b, and end surfaces 13a,13 b. Assuming a central axis 15 connecting the centers of the end surfaces 13a and 13b, collector tab leads 14a and 14b are extended from the end surfaces 13a and 13b in the direction of the central axis 15. The all-solid-state battery is particularly fragile and easily broken at corners and surface portions (end faces), and therefore the configuration of each embodiment to which the present invention is applied can be more suitably applied.

Fig. 2 shows a battery cell 2 in which a battery 1 of the present invention is packaged with an outer package 3 covering the battery cell. In the battery cell 2 of the present embodiment, the top surface 21a, the bottom surface 21b, and the side surfaces 22a,22b are defined in correspondence with the battery 1. Here, side surface 22b has an extension of outer package 3 extending from bottom surface 21b within the plane of side surface 22b, and outer package 3 is positioned vertically below bottom surface 21b in fig. 2. Since the stacked battery cells 2 are generally adjacent to each other with the same size and shape, the extension of the side surface 22b has the same shape and size as the portion of the side surface 22b of the battery cell 2 that is not the extension. That is, the area of outer package 3 on side surface 22b is 2 times larger than the area of outer package 3 on side surface 22a on the opposite side.

End face folded portions 23a-1,23a-2,23b-1,23b-2, which are provided in a folded state of the exterior body 3, are formed in triangular prism shapes on the outer surfaces of the portions corresponding to the end faces 13a,13b of the battery 1. The end surface folds 23a-1,23a-2 and 23b-1,23b-2 have triangular pyramidal spaces 25a-1,25a-2 and 25b-1,25b-2 (2 on each side of the side surfaces 22a,22b, 4 in total) formed by folding in from the side surfaces 22a,22 b. Further, current collector tab lead storage portions 24a-1,24a-2 and 24b-1,24b-2, which vertically sandwich the current collector tab leads 14a,14b and are stored therein, are extended from the respective tip sides of the end surface folds 23a-1,23a-2 and 23b-1,23b-2 in the direction of the central axis 15.

Fig. 3 shows a developed view of the outer package 3. The exterior body 3 has a top surface covering portion 31a and a bottom surface covering portion 31b as portions covering the top surface 11a and the bottom surface 11b of the battery 1, a side surface covering portion 32a as a portion covering the side surface 12a, and side surface covering portions 32b-1 and 32b-2 as portions covering the side surface 12 b. The side surface covering portions 32b-1 and 32b-2 are joint portions that overlap and are joined to each other when the outer package 3 wraps the battery 1. Therefore, the side surface 22b of the battery cell 2 is configured by covering the side surface 12b of the battery 1 with the side surface covering portions 32b-1 and 32b-2 of the exterior body 3.

End face covering portions 33a-1,33a-2,33b-1,33b-2 are provided as portions covering the end faces 13a,13b of the battery 1 so as to correspond to the respective end faces on both sides in the vertical direction, and the end face covering portions 33a-1,33a-2,33b-1,33b-2 are portions forming end face folded portions 23a-1,23a-2,23b-1,23b-2 in a triangular prism shape in the battery cell 2, the folded portions folding the exterior body 3. At the tip end of the end surface covering portion 33a-1,33a-2,33b-1,33b-2 extending in the direction of the central axis 15, there is provided a collector tab lead holding portion 34a-1,34a-2,34b-1,34b-2 for holding the collector tab leads on both sides in the up-down direction. Further, three triangular pyramidal space-forming portions 35a-1,35a-21,35a-22 and 35b-1,35b-21,35b-22 are formed, and the three triangular pyramidal space-forming portions 35a-1,35a-21,35a-22 and 35b-1,35b-21,35b-22 are portions which form three triangular pyramidal spaces 25a-1,25a-2 and 25b-1,25b-2 folded from the side faces 22a,22 b. The triangular pyramidal space-forming portions 35a-21 and 35a-22 and 35b-21 and 35b-22 overlap each other, respectively, to form a triangular pyramidal space.

In the present embodiment, as shown in fig. 3, the side surface covering portion 32b-1 of the outer package 3 protrudes outward (leftward in fig. 3) from the triangular pyramid-shaped space forming portions 35a-21 and 35 b-21. The extension of the side surface covering portion 32b-1 of the outer package 3 is a portion that constitutes an extension of the side surface 22b of the battery cell 2, and the stacked battery cells 2 are generally the same size and shape as the side surfaces 22a of the adjacent battery cells 2 because the stacked battery cells 2 are adjacent to each other. Therefore, the protruding portion of the side surface covering portion 32b-1 has the same shape and size as the portions of the side surface covering portion 32b-1 that are not protruding portions or the side surface covering portions 32a and 32 b-2.

As described above, in the embodiment of the present invention, the outer package 3 is formed of one sheet of film integrally provided with the extension portion extending from the side surface covering portion 32b-2, so that the number of bonding portions at the time of packaging can be reduced as much as possible, and the sealing performance can be improved, and the extension portion of the outer package 3 in the side surface 22b of the battery cell 2 is naturally generated in the manufacturing process when the battery 1 is packaged with one sheet of film of the outer package 3, so that the manufacturing efficiency can be high.

In one embodiment of the present invention, when the battery cells 2 are stacked in the horizontal direction and modularized, as shown in fig. 4, the inner surface portions of the extension portions 22c of the exterior body 3 of the battery cells 2 are welded to the outer surface portions of the side surfaces 22a of the adjacent battery cells 2, and are joined by face bonding. Since the cells 2 are prevented from sliding and restricted from each other by the welding, a uniform surface pressure can be applied to the surfaces of the cells 2, and variations in load due to positional displacement between adjacent cells 2 can be avoided. Therefore, the adjacent battery cells 2 are not subjected to an excessive load due to the mutual positional deviation, and the battery 2 is not damaged.

Here, the extension 22c of the exterior body 3 of the battery cell 2 is preferably the same shape and size as the side surface 22a of the adjacent battery cell 2. If these shapes and dimensions are different from each other, unevenness occurs in the side surfaces 22a and 22b of the battery cell 2 due to the difference in the shapes and dimensions, and the load applied to the side surfaces 22a and 22b varies, which increases the possibility of damaging the battery cell 2 due to an excessive load. Specifically, when the protruding portion 22c is smaller than the side surface 22a, when the battery cell 2 is fixed by a module component, the protruding portion 22c does not cover the entire side surface 22a of the adjacent battery cell 2, and thus there are a portion to which the fixing pressure is applied and a portion to which the fixing pressure is not applied on the side surfaces 12a and 12b of the battery 1, and uneven load is applied to the side surfaces and the electrodes, which may damage the electrodes. When the protruding portion 22c is larger than the side surface 22a, when the battery cell 2 is fixed by the module structural member, the protruding portion 22c covers a part of the side surface 22a of the battery cell 2 adjacent to the adjacent battery cell 2, and a part to which a fixing pressure is applied is larger than usual in the side surfaces 12a and 12b of the battery 1, and an uneven load is applied to the side surfaces 12a and 12b, thereby damaging the electrodes. Further, when the extension portion 22c is larger than the side surface 22a, not only the exposed portion may be damaged, but also there is a problem that the energy density of the module is lowered due to an extra portion.

When the battery cells 2 are stacked in this order in the horizontal direction, as can be seen from fig. 4, welded portions where the inner surface of the protruding portion 22c of the exterior body 3 of the battery cell 2 and the side surfaces of the adjacent battery cells are welded are alternately arranged in the vertical direction of the stacked body.

At this time, the side surface opposite to the welded portion is covered with the films of the two exterior bodies 3 when the battery is packaged with the films of the exterior bodies. The side surfaces on the welded portion side are covered with two films of the exterior body 3, and the two films of the exterior body 3 also include a portion of the film extending from the adjacent battery cell 2. Thus, the sides of all the cells of the stacked battery cells are protected by the two sheets of film. The top surface 21a side and the bottom surface 21b side of each battery cell 2 are in contact with the bottom surface 21b side and the top surface 21a side of the adjacent battery cell 2 through the film of one exterior body 3, respectively, and are protected from external force. Therefore, the entire modularized stacked body of the battery cells 2 is firmly protected from external force.

Here, the all-solid battery cell has a technical problem that the surface is fragile and easily broken, and the all-solid battery cell itself needs to be firmly protected. Therefore, the following structure of the present invention is effective particularly when applied to an all-solid battery cell, that is: a structure for preventing damage to the battery due to a local excessive load caused by a positional displacement, in such a manner that the positional relationship between the battery cells is fixed to each other without causing the positional displacement when the battery cells are stacked; and a structure in which the entire side surface is doubly covered with the film of outer package 3 at the time of modularization, and thus is strongly protected. While the embodiments of the present invention have been described above with reference to the examples, it is needless to say that the present invention is not limited to the examples described above, and can be variously implemented within a range not departing from the gist of the present invention.

Reference numerals

1: battery with a battery cell

11 a: the top surface

11 b: bottom surface

12a,12 b: side surface

13a,13 b: end face

14a,14 b: collector tab lead

15: center shaft

2: battery monomer

21 a: the top surface

21 b: bottom surface

22a,22 b: side surface

22 c: extension of outer package

23a-1,23a-2,23b-1,23 b-2: end face folding part

24a-1,24a-2,24b-1,24 b-2: collector tab lead storage

25a-1,25a-2,25b-1,25 b-2: space portion of triangular pyramid shape

3: external packing body

31 a: top surface covering part

31 b: bottom covering part

32a,32b-1,32 b-2: side covering part

33a-1,33a-2,33b-1,33 b-2: end face covering part

34a-1,34a-2,34b-1,34 b-2: clamping part for lead of current collecting tab

35a-1,35a-21,35a-22,35b-1,35b-21,35 b-22: triangular pyramid space forming part