JP2021182493A - Battery cell - Google Patents

Abstract

To provide a laminated cell type battery in which a current collector tab lead is sandwiched and accommodated from above and below by an exterior body, and that suppresses the influence of external force on the current collector tab lead even when an external force is applied to a place where the current collector tab lead is accommodated.SOLUTION: In a battery cell that includes a battery and an exterior body that accommodates the battery, and in which a current collector tab lead extends from one end surface of the battery, the exterior body has a structure that reduces the influence of external force on a portion covering the end surface on which the current collector tab lead of the battery protrudes or a portion sandwiching and accommodating the current collector tab lead.SELECTED DRAWING: Figure 4

Description

The present invention relates to a battery cell, particularly a battery cell sealed by an exterior body.

In recent years, with the spread of electric and electronic devices of various sizes such as automobiles, personal computers, and mobile phones, the demand for high-capacity and high-output battery devices is rapidly expanding. Examples of such a battery device include a liquid-based battery cell that uses an organic electrolyte as an electrolyte between the positive electrode and the negative electrode, and a solid battery cell that uses a flame-retardant solid electrolyte instead of the electrolyte of the organic electrolyte. Can be mentioned.

In such a battery device, a laminated cell type battery cell in which a battery is wrapped in a laminated film (exterior body) and sealed in a plate shape is known. In applications such as EVs and HEVs, a battery cell assembly in which a plurality of such laminated cell type battery cells are arranged side by side and stored in a case is used. By wrapping it in an outer body, it is possible to prevent the invasion of the atmosphere into the battery (for example, Patent Document 1). In the present specification, the "battery" refers to a member composed of a laminated body of battery elements composed of positive and negative electrodes and an electrolyte, and a current collector tab lead, and the battery is wrapped in a laminated film (exterior body). The one sealed with is called a "battery cell".

In addition, for the purpose of effectively improving the volumetric energy density of the battery module while maintaining the airtightness of the laminated film (exterior body), the exterior body in which one film is folded back to accommodate the battery is provided. A battery cell including the battery cell is disclosed (Patent Document 2). According to Patent Document 2, this battery cell can effectively improve the volumetric energy density of the battery module while maintaining the hermeticity of the exterior body. Further, Patent Document 2 also describes a configuration in which a current collector tab lead is sandwiched and accommodated from above and below by an exterior body in such a battery cell.

Japanese Unexamined Patent Publication No. 2012-169204 WO2019 / 188825

In the case of a laminated cell type battery cell that has a structure in which the current collecting tab lead is sandwiched from above and below by an exterior body and accommodated, when an external force is applied to the place where the current collecting tab lead is accommodated, the current collecting tab lead becomes a current collecting tab lead. Stress will be applied and the electrodes may crack.

INDUSTRIAL APPLICABILITY The present invention is a laminated cell type battery cell in which a current collector tab lead is sandwiched and accommodated by an exterior body from above and below, and even when an external force is applied to a portion where the current collector tab lead is accommodated, the external force is applied. The purpose is to suppress the influence on the current collector tab lead.

In order to solve the above problems, the battery cell of the present invention is a battery cell including a battery and an exterior body for accommodating the battery, and a current collector tab lead is extended from one end surface of the battery. The exterior body is characterized in that a structure for reducing the influence of an external force is provided at a position covering the end surface of the battery where the current collecting tab lead protrudes or a place where the current collecting tab lead is sandwiched and accommodated.

By providing a structure for reducing the influence of the external force at the place where the current collecting tab lead of the battery covers the protruding end surface or the place where the current collecting tab lead is sandwiched and accommodated, the external force is applied to the place where the current collecting tab lead is housed. Even when it is applied, the influence of the external force on the current collecting tab lead can be suppressed, and the possibility that the electrode is cracked due to stress applied to the current collecting tab lead can be reduced.

In the present invention, it is a laminated cell type battery cell, and an external force is applied to a place where the outer body of the laminated film covers the end face on which the current collecting tab lead of the battery protrudes or a place where the current collecting tab lead is sandwiched and accommodated. In the case of providing a structure for reducing the influence of the above, the exterior body is characterized by being made of one film.

By making the exterior body made of one film, it is possible to reduce the number of joints at the time of packaging as much as possible and improve the airtightness.

Further, in the present invention, in this case, the one film of the exterior body is in contact with and covers the top surface, the bottom surface and the two side surfaces orthogonal to the end surface on which the current collecting tab lead of the battery is extended. A portion, a portion that covers the end face on which the current collecting tab lead of the battery protrudes, is folded from the short side on both sides of the end face to form a triangular pyramid-shaped space on both sides, and is long on both sides of the end face. It consists of a portion that folds from the side and wraps the end face, and a portion that extends axially from the portion that wraps the end face and joins both the upper and lower facing surfaces to hold the current collecting tab lead. It is characterized by.

Such a form of the exterior body made of the single film is a form corresponding to the battery including the current collector tab lead and the end face on which the current collector tab lead protrudes, and the end face on which the current collector tab lead protrudes is efficient. In addition to being able to be wrapped and sealed, the current collector tab lead can be covered and sandwiched from both the upper and lower sides, and a battery in which the current collector tab lead protrudes can be efficiently packaged in a small number of steps.

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

All-solid-state battery cells are fragile and easily damaged, especially at the corners and end faces. Therefore, in the present invention, the exterior body provided with a structure for reducing the influence of an external force at a portion covering the end surface on which the current collector tab lead of the battery protrudes or a portion sandwiching and accommodating the current collector tab lead is an end surface. It is effective for application to all-solid-state battery cells in which the current collector tab lead protrudes from.

Further, in the present invention, in this case, the structure for reducing the influence of the external force is accommodated by sandwiching and accommodating the portion of the exterior body that covers the end face on which the current collecting tab lead of the battery protrudes or the current collecting tab lead. It is characterized by having a structure that increases the thickness of the portion to be used.

By increasing the thickness of the portion of the exterior body that covers the end surface of the battery where the current collecting tab lead protrudes or the portion that sandwiches and accommodates the current collecting tab lead, this portion is reinforced and the strength is increased. It is possible to suppress deformation and bending due to external force. Therefore, even if an external force is applied to this portion, deformation and bending of this portion are suppressed, and the influence of the current collecting tab lead of the external force is reduced.

Further, in the present invention, in this case, the structure for reducing the influence of the external force is accommodated by sandwiching and accommodating the portion of the exterior body that covers the end face on which the current collecting tab lead of the battery protrudes or the current collecting tab lead. It is characterized in that it has a structure in which embossing (unevenness) is provided at a portion to be embossed.

The structure for reducing the influence of the external force is provided by providing embossing (unevenness) in a portion of the exterior body that covers the end surface of the battery on which the current collecting tab lead protrudes or a portion that sandwiches and accommodates the current collecting tab lead. The deformation of this portion due to an external force can be absorbed by the embossing (unevenness), and the deformation as a whole can be suppressed. Therefore, even if an external force is applied to this portion, the deformation of this portion is absorbed by the embossing (unevenness), the deformation as a whole is suppressed, and the influence of the current collecting tab lead of the external force is reduced.

Further, in the present invention, in this case, the embossing (unevenness) extends along the direction in which the current collecting tab lead is extended at a position where the current collecting tab lead of the exterior body is sandwiched and accommodated. It is characterized by being provided in.

The embossing (unevenness) is provided at a position where the current collecting tab lead of the exterior body is sandwiched and accommodated so as to extend along the direction in which the current collecting tab lead is extended. When an external force that pulls or compresses the emboss (unevenness) in the lateral (width) direction is generated at the place where the tab lead is sandwiched and accommodated, the emboss (unevenness) is deformed so that the width expands or contracts. It is possible to absorb the deformation caused by the external force and suppress the deformation as a whole. Further, when stress is applied to the portion where the current collecting tab lead is sandwiched and accommodated in the depth direction of the embossing (unevenness), the strength is increased by providing the embossing (unevenness), and the embossing (unevenness) is increased. It becomes difficult to bend in the depth direction, and the influence on the current collecting tab lead and the current collecting tab is reduced. Therefore, the influence of the current collector tab lead of the external force is reduced.

Further, in the present invention, in this case, the embossing (unevenness) is further extended continuously to a portion on the inner surface of the exterior that covers the end surface on which the current collecting tab lead of the battery protrudes. ..

In addition to the location where the current collecting tab lead is sandwiched and accommodated, the embossing (unevenness) further extends continuously to a portion on the inner surface of the exterior that covers the end surface on which the current collecting tab lead of the battery protrudes. When an external force that pulls or compresses the emboss (concavo-convex) in the lateral (width) direction is generated at a portion of the battery that covers the protruding end surface of the current collecting tab lead, the emboss (concave and convex) has a width. Deformation that expands or contracts occurs, absorbs the deformation due to external force, and suppresses the deformation as a whole. Further, when stress is applied in the depth direction of the embossing (unevenness) at a portion of the battery covering the end surface where the current collecting tab lead protrudes, the strength is increased by providing the embossing (unevenness), and the embossing (unevenness) is increased. It becomes difficult to bend in the depth direction of the unevenness), and the influence on the current collecting tab lead and the current collecting tab is reduced. Therefore, the influence of the current collector tab lead of the external force is reduced.

Further, in the present invention, in this case, the embossing (unevenness) is increased in strength by welding at the position where the exterior body covers the end surface on which the current collecting tab lead of the battery protrudes, thereby preventing electrode cracking. In the trapezoidal part where welding is not performed except for the triangular part, the direction in which the current collecting tab lead is extended from one point on one side of the trapezoid to one point on another opposite side parallel to the one side. Is characterized by extending non-parallel.

The embossing (unevenness) faces parallel to one side of the trapezoidal surface at a trapezoidal portion where welding is not performed, where the exterior body covers the end surface on which the current collecting tab lead of the battery projects. By extending toward one point on another side in a direction non-parallel to the direction of the axis, an external force is generated in the long axis direction (horizontal direction) of the end surface at a position covering the end surface on which the current collecting tab lead protrudes. Even when an external force is generated in the short axis direction (vertical direction) of the end face, the deformation due to the external force can be absorbed by embossing (unevenness), and the deformation as a whole can be suppressed. Therefore, it is possible to reduce the influence of the current collector tab lead on a wide range of external forces such as the horizontal external force and the vertical external force of the end face. Further, when stress is applied in the depth direction of the embossing (unevenness) at a portion of the battery covering the end surface where the current collecting tab lead protrudes, the strength is increased by providing the embossing (unevenness), and the embossing (unevenness) is increased. It becomes difficult to bend in the depth direction of the unevenness), and the influence on the current collecting tab lead and the current collecting tab is reduced.

Further, in the embossing (unevenness) of the present invention, the exterior body covers the end surface on which the current collecting tab lead of the rectangular battery projects, from one point or a plurality of points on one side of the rectangle. It consists of a plurality of embosses (concavities and convexities) extending non-parallel to the direction in which the current collecting tab lead is extended toward a plurality of points on another side facing each other in parallel with the two sides of the rectangle. It is characterized in that at least one rectangle is formed by two embosses (unevenness).

The current collection of external force due to absorption of stress applied in the width direction of the emboss (concavo-convex) due to deformation of the emboss (concavo-convex) and increase in strength against stress applied in the depth direction of the emboss (concavo-convex). The effect of reducing the influence on the tab lead is enhanced by the presence of a plurality of embosses (unevenness).

Further, in the embossing (unevenness) of the present invention, the exterior body covers the end surface of the rectangular battery from which the current collecting tab lead protrudes, from one point or a plurality of points on one side of the rectangle. It consists of a plurality of embosses (concavities and convexities) extending non-parallel to the direction in which the current collecting tab lead is extended toward a plurality of points on another side facing the same as one side of the rectangle. It is characterized in that at least one triangle is formed by two embosses (unevenness).

The strength against the stress applied in the depth direction of the emboss (unevenness) is that two embosses (unevenness) intersect at one point on the side of the rectangle, and another one side of the rectangle and two embosses. It is maximized when a triangle is formed by (unevenness), and the effect of reducing the influence of an external force on the current collecting tab lead is maximized.

As described above, according to the present invention, the present invention places an external force in a place where the exterior body accommodating the battery in which the current collecting tab lead protrudes covers the end surface of the battery in which the current collecting tab lead protrudes or a place where the current collecting tab lead is sandwiched and accommodated. By providing a structure that reduces the influence of the current collector tab lead, even when an external force is applied to the place where the current collector tab lead is housed, the influence of the external force on the current collector tab lead can be suppressed, and stress is applied to the current collector tab lead. In addition, it has the effect of reducing the possibility of the electrode cracking.

It is a perspective view of the battery in the battery cell of this invention. It is a perspective view which shows the appearance of the battery cell of this invention. It is a development view of the exterior body of the battery cell of this invention. It is a figure which shows the part where the thickness is increased in the perspective view of the battery cell of this invention. It is a figure which shows the part where the thickness is increased in the development view of the exterior body of this invention. It is a figure which shows the embossing (unevenness) extending in the central axis direction in the perspective view of the battery cell of this invention. It is a figure which shows the embossing (unevenness) extending in the central axis direction in the development view of the exterior body of this invention. It is a figure which shows the embossing (unevenness) which is not parallel to the central axis in the perspective view of the battery cell of this invention. It is a figure which shows the embossing (unevenness) which is not parallel to the central axis in the development view of the exterior body of this invention. It is a figure which shows a plurality of embossing (unevenness) which is not parallel to a central axis in the development view of the exterior body of this invention. It is a figure which shows another plurality of embossing (unevenness) which is not parallel to a central axis in the development view of the exterior body of this invention. It is a figure which shows the further plurality of embossing (unevenness) which is not parallel to a central axis in the development view of the exterior body of this invention.

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

The battery 1 of the present invention is an all-solid-state battery in the embodiment, and has a rectangular parallelepiped shape as shown in FIG. Has a surface. When the central axis 15 connecting the centers of the end faces 13a and 13b is assumed, the current collecting tab leads 14a and 14b extend from the end faces 13a and 13b in the direction of the central axis 15, respectively. Since the all-solid-state battery is fragile and easily damaged especially at the corners and the surface (end face), it can be said that it is more suitable for applying the configuration of each embodiment of the present invention.

FIG. 2 shows a battery cell 2 in which the battery 1 of the present invention is covered with an exterior body 3 (FIG. 3) and packaged. Also in the battery cell 2, the top surface 21a, the bottom surface 21b, and the side surfaces 22a and 22b are defined corresponding to the battery 1. The portions corresponding to the end faces 13a and 13b of the battery 1 are the end face folding portions 23a-1, 23a-2, 23b-1, 23b-2 in the form in which the exterior body 3 is folded, and are on the outer surface. It has a triangular column. Further, the end face folding portions 23a-1, 23a-2 and 23b-1, 23b-2 are formed by folding from the side surface 22a, 22b side, respectively, and are formed by folding into the triangular pyramid-shaped space portions 25a-1, 25a, respectively. -2 and 25b-1, 25b-2 are formed, two from each side, for a total of four. Then, the current collector tab leads 14a, 14b are sandwiched and accommodated from above and below in the direction of the central axis 15 from the end face folding portions 23a-1, 23a-2 and 23b-1, 23b-2. The accommodating portions 24a-1, 24a-2 and 24b-1, 24b-2 are extended.

FIG. 3 shows a developed view of the exterior body 3. The exterior body 3 has a top surface covering portion 31a and a bottom surface covering portion 31b as portions covering each of the top surface 11a and the bottom surface 11b of the battery 1, and the side surface covering portion 32a as a portion covering the side surface 12a. It has side covering portions 32b-1 and 32b-2 as portions covering the side surface 12b. The side surface covering portions 32b-1 and 32b-2 are adhesive portions that are overlapped with each other and adhered to each other when the exterior body 3 covers and wraps the battery 1. Therefore, the side surface 12b of the battery 1 is doubly covered by the side surface covering portions 32b-1 and 32b-2 of the exterior body 3.

As the portion covering the end faces 13a and 13b of the battery 1, the end face folding portions 23a-1, 23a-2, 23b-1 and the like, which have a triangular columnar shape in which the exterior body 3 is folded in the battery cell 2, are formed. The end face covering portions 33a-1, 33a-2, 33b-1, 33b-2 forming 23b-2 are provided corresponding to the vertical directions of the end faces on both sides. A current collector tab lead holding portion 34a-that sandwiches the current collector tab leads 14a, 14b on both sides from above and below after extending the end face covering portions 33a-1, 33a-2, 33b-1, 33b-2 in the central axis 15 direction. 1,34a-2, 34b-1, 34b-2 are provided. Further, the triangular pyramid-shaped space forming portion 35a, which is a portion forming the triangular pyramid-shaped space portions 25a-1, 25a-2 and 25b-1, 25b-2 formed by being folded from the side surface 22a, 22b side. -1,35a-21,35a-22 and 35b-1,35b-211,35a-22 are formed. The triangular pyramid space forming portions 35a-21 and 35a-22 and 35b-21 and 35b-22 overlap each other to form a triangular pyramid space.

In one embodiment of the present invention, the thickness of the portion of the exterior body 3 that covers the end face on which the current collector tab leads 14a, 14b of the battery protrudes or the portion that sandwiches and accommodates the current collector tab leads 14a, 14b. The structure is to increase the thickness. When this embodiment is shown in the perspective view of FIG. 4 and the developed view of FIG. 5, the thickness of the shaded portion in both figures is increased. Specifically, in the perspective view of FIG. 4, the end face folding portions 23a-1, 23a-2, 23b-1, 23b-2 and the current collector tab leads 14a, 14b in the form in which the exterior body 3 is folded are shown. The current collecting tab lead accommodating portions 24a-1, 24a-2, 24b-1, and 24b-2 that are sandwiched and accommodated from above and below are thickened. As shown in the developed view of FIG. 5, the current collecting tab lead holding portions 34a-1, which sandwich the end face covering portions 33a-1, 33a-2, 33b-1, 33b-2 and the current collecting tab leads 14a, 14b on both sides from above and below. Thicken 34a-2, 34b-1, 34b-2. By making these parts thicker, it is possible to reinforce these parts, increase the strength, and suppress deformation and bending due to external force. Therefore, even if an external force is applied to these portions, deformation and bending of these portions are suppressed, and the influence of the external force on the current collector tab leads 14a and 14b is reduced.

In another embodiment of the present invention, the exterior body 3 is embossed at a portion of the exterior body 3 that covers the end face on which the current collector tab leads 14a, 14b of the battery protrude, or a portion that sandwiches and accommodates the current collector tab leads 14a, 14b. It is a structure that provides (unevenness). The embossing (unevenness) may be provided on the inner surface side or may be provided on the outer surface side. As an example of embossing (unevenness), embossing (unevenness) extending in the direction of the central axis 15 may be used at a position where the current collector tab leads 14a and 14b are sandwiched and accommodated. When this embodiment is shown in the perspective view of FIG. 6 and the developed view of FIG. 7, specifically, it is represented by the current collector tab lead accommodating portion 24a-1 of FIG. 6 and the current collector tab lead holding portion 34a-1 of FIG. It is embossed (unevenness) 4-1. This embossing (unevenness) is further embossed (unevenness) 4-2 up to the end face folding portion 23a-1 in the form in which the exterior body 3 of FIG. 6 is folded, and up to the end face covering portion 33a-1 in FIG. It may be additionally stretched as.

The direction in which the current collector tab leads 14a and 14b are extended, that is, the central axis 15 at a position where the embossed (unevenness) 4-1 sandwiches and accommodates the current collector tab leads 14a and 14b of the exterior body 3. By being provided so as to extend in the direction of the above, the embossed (unevenness) 4-1 is pulled or compressed in the lateral (width) direction at a position where the current collector tab leads 14a and 14b are sandwiched and accommodated. When an external force is generated, the embossed (unevenness) 4-1 is deformed so as to expand or contract in width to absorb the deformation due to the external force, and the deformation as a whole can be suppressed. Further, when stress is applied in the depth direction of the embossed (unevenness) 4-1 at a position where the current collector tab leads 14a and 14b are sandwiched and accommodated, the embossed (unevenness) 4-1 is provided to provide strength. Is increased, and it becomes difficult to bend in the depth direction of the embossed (unevenness) 4-1 and the influence on the current collecting tab leads 14a and 14b and the current collecting tab is reduced. The embossing (unevenness) 4-1 further extends as an embossing (unevenness) 4-2 continuously to a portion on the inner surface of the exterior body 3 that covers the end surface on which the current collecting tab leads 14a and 14b of the battery project. The embossed (unevenness) 4-2 is laterally placed in a place where the current collecting tab leads 14a and 14b are sandwiched and accommodated, and also in a place where the current collecting tab leads 14a and 14b of the battery cover the protruding end surface. When an external force that pulls or compresses in the width) direction is generated, the embossed (unevenness) 4-2 is deformed so that the width expands or contracts, absorbs the deformation due to the external force, and suppresses the deformation as a whole. be able to. Further, when stress is applied in the depth direction of the emboss (concavo-convex) 4-2 at a position covering the end surface where the current collecting tab leads 14a and 14b of the battery project, the emboss (concave and convex) 4-2 is provided. As a result, the strength is increased, the embossing (unevenness) 4-2 is less likely to bend in the depth direction, and the influence on the current collecting tab leads 14a and 14b and the current collecting tab is reduced. Therefore, the influence of the current collector tab leads 14a and 14b of the external force is reduced.

As another example of embossing (unevenness), the exterior body 3 is welded at a portion (the end face folding portion 23a-1 of the battery cell 2) where the exterior body 3 covers the end face on which the current collecting tab leads 14a and 14b of the battery project. 4-3 Embossed (concavo-convex) extending from one point on one side of the trapezoid to one point on another opposite side parallel to the one side, non-parallel to the direction of the axis. May be. This embodiment will be described with reference to the perspective view of FIG. 8 and the developed view of the exterior body 3 of FIG. After forming the top surface covering portion 31a, the bottom surface covering portion 31b, and the side surface covering portions 32a-1, 32a-2), the space portions 25a-1, 25a-2 and 25b having a triangular pyramid shape are folded from the side surface 12a, 12b side. When forming -1,25b-2, the exterior to which the triangular pyramid-shaped space forming portions 35a-1,35a-21,35a-22 and 35b-1,35b-21,35b-22 of the exterior body 3 are joined. The inner surface portion of the body 3 on the other side is represented as a shaded portion in FIG. Regarding the shaded portion in FIG. 9, as shown in the shaded portion on the upper right, the square portion on the side of the current collecting tab lead holding portion 34b-2 requires welding and is an essential portion for welding. On the other hand, the triangular portion on the end face covering portion 33b-2 side is a portion where welding is not essential, but the strength is increased by welding to prevent electrode cracking, so to speak, it can be said that welding is a desired portion. It is a part.

As can be seen from FIG. 9, the end face covering portions 33a-1, 33a-2, 33b-1, 33b-2 of the exterior body 3 have the above-mentioned desired welding portions (strength increases by welding and electrode cracking). It will have a trapezoidal part to which the welded part is not applied, except for the triangular part) that prevents the welding. An example of the embossed (unevenness) 4-3 of the present embodiment is a trapezoidal ABCD formed on the end face covering portion 33a-1 of the exterior body 3 shown in FIG. 9 from one point on the side AB to the side AB. It is an emboss (concavo-convex) extending non-parallel to the direction of the central axis 15 (the direction in which the current collecting tab leads 14a and 14b extend) toward one point on the side CD parallel to the side CD.

Even when an external force is generated in the long axis direction (horizontal direction) of the end face at the portion covering the end face where the current collecting tab leads 14a and 14b project (the end face folding portion 23a-1 of the battery cell 2). Even when an external force is generated in the short axis direction (vertical direction) of the end face, the deformation due to the external force can be absorbed by the embossing (unevenness) 4-3, and the deformation as a whole can be suppressed. Therefore, it is possible to reduce the influence of the current collector tab leads 14a and 14b on a wide range of external forces such as the horizontal external force and the vertical external force of the end face. Further, when stress is applied in the depth direction of the embossed (unevenness) 4-3 at a position covering the end surface where the current collecting tab leads 14a and 14b of the battery project, the embossed (unevenness) 4-3 is provided. As a result, the strength is increased, the embossing (unevenness) 4-3 is less likely to bend in the depth direction, and the influence on the current collecting tab leads 14a and 14b and the current collecting tab is reduced.

The exterior body 3 is embossed so as to extend non-parallel to the direction of the axis at a portion (the end face folding portion 23a-1 of the battery cell 2) where the current collecting tab leads 14a and 14b of the battery cover the protruding end faces. Further various forms can be considered for (unevenness).

The exterior body 3 forms a portion (the end face folding portions 23a-1, 23a-2, 23b-1, 23b-2 in the battery cell 2) where the current collecting tab leads 14a and 14b of the battery cover the protruding end faces. The end face covering portions 33a-1, 33a-2, 33b-1, 33b-2) of the exterior body 3 are rectangular. In FIG. 10, in the rectangle, the current collector tab leads 14a and 14b are extended from one point or two points on one side of the rectangle toward two points on another opposite side parallel to the one side. Those having two embosses (unevenness) extending non-parallel to the direction are described. The current collection of external force due to absorption of stress applied in the width direction of the emboss (concavo-convex) due to deformation of the emboss (concavo-convex) and increase in strength against stress applied in the depth direction of the emboss (concavo-convex). The effect of reducing the influence on the tab leads 14a and 14b is enhanced by the presence of a plurality of embosses (unevenness).

In FIG. 11, the current collecting tab leads 14a and 14b extend from the three points on one side of the rectangle toward the three points on the opposite side parallel to the one side, in a direction non-parallel to the extending direction. It is described that the rectangle is composed of three embosses (unevenness), and two sides of the rectangle and three embosses (unevenness) form two quadrangles. Further, in FIG. 12, the current collecting tab leads 14a and 14b are not parallel to the direction in which the current collecting tab leads 14a and 14b are extended from the two points on one side of the rectangle toward the two points on the other opposite side parallel to the one side. It is described that the rectangle is composed of three embosses (concavo-convex), and two sides of the rectangle and three embosses (concavo-convex) form two triangles. The strength against the stress applied in the depth direction of the emboss (unevenness) is that two embosses (unevenness) intersect at one point on the side of the rectangle, and another one side of the rectangle and two embosses. It becomes the maximum when forming a triangle by (unevenness), and the effect of reducing the influence of the external force on the current collecting tab leads 14a and 14b is the largest.

Although the embodiments of the present invention have been described above with reference to examples, the present invention is not limited to these embodiments and is carried out in various embodiments without departing from the spirit of the present invention. Of course, it can be done.

1 Battery 11a Top surface 11b Bottom surface 12a, 12b Side surface 13a, 13b End surface 14a, 14b Current collection tab lead 15 Central axis 2 Battery cell 21a Top surface 21b Bottom surface 22a, 22b Side surface 23a-1, 23a-2, 23b-1, 23b- 2 End face folding part 24a-1, 24a-2, 24b-1, 24b-2 Current collecting tab lead accommodating part 25a-1, 25a-2, 25b-1, 25b-2 Triangular pyramid-shaped space part 3 Exterior body 31a Top cover 31b Bottom cover 32a, 32b-1, 32b-2 Side cover 33a-1, 33a-2, 33b-1, 33b-2 End face cover 34a-1, 34a-2, 34b-1, 34b-2 Current collecting tab lead holding part
35a-1,35a-21,35a-22,35b-1,35b-211,35b-22
Triangular pyramid space forming part 4-1, 4-2, 4-3 Embossing (unevenness)

Claims (13)

A battery cell comprising a battery and an exterior body that houses the battery.
A current collector tab lead extends from one end face of the battery.
The exterior body is a battery cell provided with a structure for reducing the influence of an external force at a portion of the battery that covers the end surface on which the current collector tab lead protrudes or a portion that sandwiches and accommodates the current collector tab lead. The battery cell according to claim 1, wherein the exterior body is made of one film. The one film of the exterior body has a top surface orthogonal to the end surface on which the current collecting tab lead of the battery is extended, a bottom surface and a portion that is in contact with and covers two side surfaces, and the current collecting tab lead of the battery protrudes. A portion that covers the end face and is folded from the short side sides on both sides of the end face to form a triangular pyramid-shaped space on both sides, and is folded from the long side sides on both sides of the end face to wrap the end face. The battery cell according to claim 2, further comprising a portion extending in the axial direction from a portion wrapping the end face and joining both upper and lower facing surfaces to sandwich the current collecting tab lead. The battery cell according to any one of claims 1 to 3, wherein the battery is an all-solid-state battery cell made of a laminate using a solid electrolyte. The structure for reducing the influence of the external force is a structure for increasing the thickness of the portion of the exterior body that covers the end face on which the current collecting tab lead of the battery protrudes or the portion that sandwiches and accommodates the current collecting tab lead. The battery cell according to any one of claims 1 to 4. The structure for reducing the influence of the external force is a structure in which embossing (unevenness) is provided at a portion of the exterior body that covers the end surface on which the current collecting tab lead of the battery protrudes or a portion that sandwiches and accommodates the current collecting tab lead. The battery cell according to any one of claims 1 to 4. The sixth aspect of claim 6 is wherein the embossing (unevenness) is provided so as to extend along a direction in which the current collecting tab lead is extended at a position where the current collecting tab lead is sandwiched and accommodated in the exterior body. Battery cell. The battery cell according to claim 7, wherein the embossing (unevenness) further extends continuously to a portion on the inner surface of the exterior body that covers an end surface on which the current collecting tab lead of the battery protrudes. The embossing (unevenness) is a trapezoid that is not welded except for a triangular portion where the exterior body covers the end surface of the battery where the current collecting tab lead protrudes, and the strength is increased by welding to prevent electrode cracking. 6. The sixth aspect of claim 6, wherein the current collecting tab lead extends from one point on one side of the trapezoid to one point on another side parallel to the trapezoid in parallel with the direction in which the collector tab lead is extended. Battery cell. The embossing (unevenness) is a position where the exterior body covers the end surface of the rectangular battery from which the current collecting tab lead protrudes, from one point on one side of the rectangle or a plurality of embossing (unevenness) starting points to the one side. A claim comprising a plurality of embosses (concavities and convexities) extending non-parallel to the direction in which the current collecting tab lead is extended toward one point or a plurality of embossed (concavo-convex) end points on another parallel opposite side. The battery cell according to 6. The battery cell according to claim 10, wherein a plurality of embossing (unevenness) extends from each of one point or a plurality of embossing (unevenness) starting points on one side of the rectangle. The battery cell according to claim 10, wherein at least one quadrangle is formed by the two sides of the rectangle and the two embosses (unevenness). The battery cell according to claim 10, wherein at least one triangle is formed by one side of the rectangle and two embosses (unevenness).

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