WO2022141259A1

WO2022141259A1 - Battery package casing and battery

Info

Publication number: WO2022141259A1
Application number: PCT/CN2020/141669
Authority: WO
Inventors: 夏恒涛
Original assignee: 宁德新能源科技有限公司
Priority date: 2020-12-30
Filing date: 2020-12-30
Publication date: 2022-07-07
Also published as: CN114008839A

Abstract

Disclosed are a battery package casing and a battery, which can reduce the probability of batteries being damaged. The battery package casing provided by the present application comprises an accommodation space, which is defined by a plurality of walls, and first foil layers and second foil layers are distributed on different areas of the walls. The hardness of the first foil layer is greater than that of the second foil layer, and the difference between a hardness value of the first foil layer and a hardness value of the second foil layer is greater than or equal to HB300.

Description

Battery case and battery

technical field

The present application relates to the field of batteries, in particular to a battery packaging case and a battery.

Background technique

Traditional batteries are very prone to damage. Once the battery is damaged, it will not only cause economic damage, but also the reaction solution inside the battery is likely to leak out, pollute the environment, and even cause a short circuit at the sharp corners, causing the battery to smoke, catch fire or even explode. Danger.

There is an urgent need to propose a new battery packaging foil to reduce the probability of battery breakage.

SUMMARY OF THE INVENTION

In view of this, the present application provides a battery packaging case and a battery, which can reduce the probability of damage to the battery.

A battery packaging case provided by the present application includes an accommodating space surrounded by a plurality of walls, and a first foil layer and a second foil layer are distributed in different regions of the walls, and the hardness of the first foil layer is greater than that of the first foil layer. The hardness of the second foil layer, and the difference between the hardness values of the first foil layer and the second foil layer is greater than or equal to HB300.

Since the difference in hardness between the first foil layer and the second foil layer is greater than or equal to HB300, the minimum hardness of the first foil layer is HB300, which has sufficient strength to protect the battery cells installed in the battery packaging case . In addition, the hardness of the second foil layer is relatively low, which is convenient for users to process, and reduces the processing difficulty in preparing the battery packaging case.

The number of the walls is at least 4, and each wall is connected by edges to enclose the enclosed accommodation space, and the first foil layer is distributed in the middle area of the walls, which can greatly strengthen the battery packaging case. strength.

Since the battery packaging case is easily knocked against the corner of the battery packaging case when it is dropped, the first foil layer is distributed at the intersection of any three or more of the walls. The first foil layer can effectively protect the corners of the battery packaging case and prevent the corners of the battery packaging case from being damaged when the battery packaging case is dropped.

The battery packaging case further includes: a safety valve mounted on the first surface of the wall and penetrating the wall in a direction perpendicular to the first surface of the wall. In this way, when the battery cells loaded in the battery packaging case react to generate gas, etc., the safety valve can be opened to release the pressure, so as to prevent the battery packaging case from malfunctioning and causing the battery packaging case to burst.

The density of the second foil layer is lower than the density of the first foil layer to reduce the total weight of the battery packaging case.

A first material layer is disposed between the first foil layer and the second foil layer, and the material of the first material layer includes at least one of polypropylene material or polyacrylated material. The first material layer has a certain buffering effect, which can buffer the stress between the first foil layer and the second foil layer, and has the effect of anti-shock, and can absorb a part of the shock when the battery packaging case is dropped , to prevent damage to the battery packaging case.

The battery packaging case further includes a base material, the first surface of the base material is disposed toward the outside of the battery packaging case, the first foil layer and the second foil layer are both formed on the first surface of the base material, The substrate serves to connect the first and second foil layers.

The first foil layer includes at least one of a stainless steel layer, a titanium alloy layer, and an aluminum alloy layer, the second foil layer includes an aluminum layer, and the base material includes a polypropylene layer, conforming to the hardness value difference greater than or equal to HB300 requirements.

The battery packaging case further includes: a second material layer located at least between the first foil layer and the substrate, and at least between the second foil layer and the substrate, the second The viscosity of the material layer is greater than the preset value. The second material layer can bond the first foil layer and the substrate, and bond the second foil layer and the substrate. In addition, when the second material layer is only located between the first foil layer and the base material, and between the second foil layer and the base material, while playing an adhesive role, It is also possible to save the amount of the second material layer and save the material cost.

Since the hardness of the second foil layer is lower than the hardness of the first foil layer, the second foil layer is easily scratched during use. Therefore, the first surface of the second foil layer is formed with The third material layer is used to protect the surface of the second foil layer and prevent the surface of the second foil layer from being scratched.

The material of the third material layer includes at least one of nylon material or resin material.

The thickness of the first foil layer is greater than the thickness of the second foil layer, and the first surface of the third material layer located on the same side of the battery packaging case is flush with the first surface of the first foil layer . In this way, the outer shell of the battery packaging case can be ensured to be flat, which facilitates assembly and facilitates storage of the battery packaging case.

A battery provided by the present application includes: the battery packaging case; and a battery core, which is arranged in the battery packaging case.

The battery packaging case is a hexahedral packaging case, and the first foil layer is distributed in the middle area of each wall of the hexahedral packaging case. The middle area of each wall is the area where the battery is most likely to be impacted. Therefore, arranging the first foil layer in the middle area of each wall can effectively improve the service life of the battery and prevent the battery from Drops, collisions, etc. cause damage to the middle area of the wall, thereby causing damage to the battery and affecting the service life of the battery.

Since the battery packaging case is easily knocked against the corners of the battery packaging case when it is dropped, the first foil layer is also distributed at the corners of the hexahedral packaging case to effectively protect the battery The corners of the packaging case prevent the corners of the battery packaging case from being damaged when the battery packaging case is dropped.

The hexahedral packaging shell includes a first wall, and the intersection of the first wall and other walls is an edge sealing area, and the second foil layer is distributed in the edge sealing area.

The battery packaging case and the battery of the present application use the first foil layer and the second foil layer with a hardness difference of at least HB300, so the minimum hardness of the first foil layer is HB300, which can effectively improve the hardness of the battery packaging case and the battery, reduce the The probability of breakage of the battery and the battery case can also be simplified due to the lower hardness of the second foil layer.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present application more clearly, the following briefly introduces the drawings that are used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can also be obtained from these drawings without creative effort.

1 is a schematic structural diagram of a battery packaging case in a first embodiment of the present application;

FIG. 2 is a schematic top view of the structure of the first wall 105 in the first embodiment of the present application;

3 is a schematic side view of the structure of the first wall 105 in the first embodiment of the present application;

4 is a schematic structural diagram of a battery packaging case according to a second embodiment of the present application;

5 is a schematic structural diagram of a battery packaging case according to a third embodiment of the present application;

FIG. 6 is a schematic structural diagram of the battery according to an embodiment of the present application.

Detailed ways

The inventors have found that the reason why the battery is prone to damage in the prior art is that the battery usually uses an aluminum film as the packaging shell.

In addition, because the battery will generate heat and gas during use, and the aluminum film has low hardness and is prone to deformation, the battery is prone to bulge during use, causing short-circuiting at sharp corners, causing the battery to emit smoke, Fire or even explosion.

The inventor's research also found that if a single material with higher hardness such as a steel foil is used to prepare the battery packaging case, although the disadvantage of the lower hardness of the aluminum film can be overcome, due to the higher hardness of these materials, the production The battery packaging case has high processing difficulty, low output and high cost, and is very unsuitable for large-scale industrial production.

In order to overcome the above problems, the inventor proposes a battery packaging case and a battery.

Please refer to FIGS. 1 and 2 , wherein FIG. 1 is a schematic structural diagram of the battery packaging case in the first embodiment of the present application, and FIG. 2 is a top-view structural schematic diagram of the first wall 105 in the first embodiment of the present application.

In the first embodiment, the battery packaging case 100 includes an accommodating space surrounded by a plurality of walls 101 (see FIG. 2 for details). Different regions of the wall 101 are distributed with a first foil layer 102 and a second foil layer 103, and the hardness of the first foil layer 102 is greater than that of the second foil layer 103, and the first foil layer 102 and The difference in hardness of the second foil layer 103 is greater than or equal to HB300.

Since the difference in hardness between the first foil layer 102 and the second foil layer 103 is greater than or equal to HB300, the minimum hardness of the first foil layer 102 is HB300, which is strong enough to protect the The battery cells in the battery packaging case 100 are described. In addition, the hardness of the second foil layer 103 is relatively low, which is convenient for the user to process and form the battery packaging case and realize the soft packaging process.

Since the shape of the battery cells is generally hexahedral, the battery packaging case 100 is also a hexahedral packaging case, which is consistent with the shape of the battery cells to be assembled. In the first embodiment, the shape of the battery cell to be packaged is a rectangular parallelepiped, the battery packaging case 100 has the same shape as the battery cell, and is a rectangular parallelepiped packaging case, and the size of the battery packaging case 100 is slightly larger than that of the battery cell. It has six walls 101, and the edges of each wall 101 are connected to enclose the cuboid space.

In fact, the shape of the battery packaging case 100 can be set according to the shape of the battery cell, and is not limited to the hexahedral packaging case in FIG. 1 .

Please refer to FIG. 1 , FIG. 2 and FIG. 3 at the same time, wherein FIG. 3 is a schematic side view of the wall in the first embodiment.

The side of the wall 101 facing the inside of the battery packaging case is the second surface of the substrate 300 . The first surface 3001 of the substrate 300 is opposite to the second surface of the substrate 300 and faces the battery packaging. The case 100 is provided externally.

The first foil layer 102 and the second foil layer 103 are distributed in different regions of the first surface 3001 of the substrate 300 , and the first surfaces of the first foil layer 102 and the second foil layer 103 face the battery The packaging case 100 is provided outside.

The first foil layer 102 includes at least one of a stainless steel layer, a titanium alloy layer, and an aluminum alloy layer, the second foil layer 103 includes an aluminum layer, and the substrate 300 includes a polypropylene layer. Using these material layers as the first foil layer 102 and the second foil layer 103 can effectively improve the hardness of the battery packaging case 100, and through the distribution of the first foil layer 102 and the second foil layer 103 Planning can effectively reduce the processing difficulty of the battery packaging case 100 .

Since the middle area of each wall 101 is the area where the battery is most likely to be impacted, in the first embodiment, the first foil layer 102 is provided in the middle area of each wall 101 to prevent the battery from falling, In the event of a collision, the middle area of the wall 101 is damaged, resulting in damage to the battery cells packaged inside the battery packaging case 100 , affecting the service life of the battery, and the shape and size of the middle area can be set by the user as required.

In the first embodiment shown in FIGS. 1 and 2 , the shape of the middle region is a rectangle, and the shape and size of the first foil layer 102 in the middle region are the same as the shape and size of the middle region. . The shape of the first foil layer 102 in the middle area is similar to the shape of the wall 101 of the battery packaging case 100 , and the ratio of the first foil layer 102 in the middle area to the corresponding side of the wall 101 is greater than or equal to 0.6 .

When the battery packaging case 100 is dropped, it is easy to knock against the corners of the battery packaging case 100 . Therefore, in the first embodiment shown in FIG. 1 , the intersections of any three or more of the walls are slightly distributed. The first foil layer 102, the first foil layer 102 with higher hardness can effectively protect the corners of the battery packaging case 100 and prevent the corners of the battery packaging case 100 from being damaged when dropped.

In fact, as shown in FIG. 4 , the first foil layer 102 may be distributed only in the middle area of the wall 101 , or as shown in FIG. 5 , the first foil layer 102 may be distributed only at the intersection of three or more walls. The first foil layer 102 and the specific distribution area of the first foil layer 102 can be set according to actual requirements.

When preparing the battery packaging case 100, the foil needs to be bent to form each wall 101 to enclose the accommodating space. Therefore, in the area where the foil is expected to be bent, a second foil with lower hardness is distributed. The foil layer 103 , that is, the second foil layer is distributed at the edge of each of the walls 101 , so as to reduce the difficulty of processing when preparing the battery packaging case 100 .

In fact, the distribution area of the second foil layer 103 can also be set as required. In the first embodiment, the second foil layer 103 is distributed in all other areas except the middle area of each wall 101 and the corners where the first foil layer 102 is distributed.

In the first embodiment, the first foil layer 102 is a stainless steel layer, the second foil layer 103 is an aluminum layer, and the hardness of the stainless steel layer ranges from HB600 to HB660, and the hardness of the aluminum layer ranges from HB62 to HB150. The hardness difference between the two is at least HB450, which is greater than the hardness difference HB300 required by the composite foil 100 , and meets the hardness requirements for the first foil layer 102 and the second foil layer 103 .

In the first embodiment, the thickness of the stainless steel layer is in the range of 0.04mm-0.150mm, and the thickness of the aluminum layer is in the range of 0.05mm-0.180mm. In this thickness range, the battery packaging case 100 can play a better protective role. In fact, the thickness distribution of the stainless steel layer and the aluminum layer can also be set as required.

A second material layer 301 is formed on the first surface of the substrate 300 for adhering the first foil layer 102 and the second foil layer 103 , and the second material layer 301 is disposed at least on the substrate 300 and the first foil layer 102, and between the substrate 300 and the second foil layer 103, while achieving adhesion, the amount of the second material layer 301 is reduced to reduce Material cost, environmental protection effect.

The viscosity of the second material layer 301 should be high enough to meet the needs of adhering the first foil layer 102 and the second foil layer 103 to the first surface of the substrate 300, preventing the first foil layer 102 and the second foil layer 103 The foil layer 102 and the second foil layer 103 are displaced relative to the substrate 300 .

This solution of forming the second material layer 301 only between the substrate 300 and the first foil layer 102 and between the substrate 300 and the second foil layer 103 is suitable for all The case where a gap is formed between the first foil layer 102 and the second foil layer 103, and no other material is filled in the gap. In fact, the specific distribution of the first foil layer 102 and the second foil layer 103 can also be planned according to needs, for example, the first foil layer 102 and the second foil layer 103 are arranged adjacent to each other, and there is no arrangement in the middle. the void.

In the first embodiment, the voids are filled with a first material layer 302 , which is not shown in FIGS. 1 and 2 , and the first material layer 302 filled here is shown in FIG. 3 .

In the first embodiment shown in FIG. 3 , the voids are filled with a first material layer 302, and the first material layer 302 is made of a material with better absorption properties, which can absorb vibration and the first foil The stress between the layer 102 and the second foil layer 103 and the shock from the outside are buffered, so as to further optimize the shock resistance of the battery packaging case 100 .

In the first embodiment, the first material layer 302 includes at least one of a polypropylene layer, a polyethylene layer, and a nylon layer. In other embodiments, the specific material composition of the first material layer 302 can also be set as required, preferably with better absorption performance.

When the first material layer 302 is provided, the second material layer 301 is also formed on the first surface 3001 of the base material 300 exposed from the gap, for bonding the first material layer 302 .

In the first embodiment, since the hardness of the second foil layer 103 is smaller than that of the second foil layer 103 , a third material layer 303 is also provided to protect the second foil layer 103 . The third material layer 303 is also not shown in FIG. 1 and FIG. 2 , but is only shown in FIG. 3 . The third material layer 303 is formed on the first surface of the second foil layer 103 and has high resistance, including corrosion resistance, abrasion resistance, etc., and can prevent the second foil layer of the battery packaging case 100 103 is worn out during use.

In some other embodiments, the third material layer 303 may also be provided to the first surface of the first foil layer 102 . In this way, the surfaces of the first foil layer 102 and the second foil layer 103 can also be protected.

The third material layer 303 is adhered to the first surfaces of the first foil layer 102 and the second foil layer 103 by glue or the like, and the material of the third material layer 303 includes at least a nylon material or a resin material. A sort of. Actually, the third material layer 303 can also be provided as required.

In the first embodiment shown in FIG. 3 , the thickness of the second foil layer 103 is smaller than the thickness of the first foil layer 102 , and the height of the third material layer 303 is the same as that of the first foil layer 102 and the first foil layer 102 . The height difference of the second foil layer 103 is matched, and the first surface of the third material layer 303 is flush with the first surface of the first foil layer 102. In this way, the outer surface of the battery packaging case is flat, which is convenient for assembly.

Please refer to FIG. 1 , FIG. 4 and FIG. 5 , the battery packaging case further includes: a safety valve 106 , which is assembled on the first surface of the wall 101 (please refer to FIG. 2 ) and is perpendicular to the first surface of the wall 101 through the wall 101 in the direction of . In this way, when the battery cells loaded in the battery packaging case 100 react to generate heat and gas, the safety valve 106 can be opened to release the pressure, so as to prevent the battery packaging case from expanding due to excessive gas in the battery packaging case. burst.

In the first embodiment shown in FIG. 1 , FIG. 4 and FIG. 5 , the battery packaging case includes only one safety valve 106 , which is arranged on the first surface of the first wall 105 and penetrates through the first wall. 105 , forming a controllable airflow channel, and controlling the opening of the safety valve 106 when necessary to discharge the gas in the battery packaging case 100 .

In fact, the specific number and arrangement of the safety valves 106 can also be set as required, for example, two safety valves 106 are provided, and the two safety valves 106 are located on both sides of the first wall 105, or Three safety valves 106 are provided, and each of the safety valves is located on each wall of the battery packaging case.

The safety valve 106 is a one-way valve, which can prevent outside air from entering the battery packaging case 100 . In fact, the safety valve 106 can also be set as a normally closed two-way valve, which is only opened when the pressure needs to be released, so it is difficult for the outside gas to enter the battery packaging case 100 .

In the first embodiment, the density of the second foil layer 103 is smaller than the density of the first foil layer 102 to reduce the total mass of the battery packaging case 100 .

A battery is also provided in the embodiments of the present application.

Please refer to FIG. 6 , which is a schematic structural diagram of a battery 600 in an embodiment of the present application.

In this embodiment, the battery 600 includes the battery packaging case 100 (as shown in FIG. 1 ) and a battery cell 601 , and the battery cell 601 is disposed in the battery packaging case 100 .

The battery cell 601 refers to an electrochemical cell containing positive and negative electrodes, which is the power storage part of the battery 600 , and can be directly used as the battery 600 after being equipped with a protection circuit and the battery packaging case 100 .

The first surface of the battery cell 601 is opposite to a predetermined area 602 on the inner surface of the battery packaging case 100 . When the battery cell 601 is assembled into the battery packaging case 100 , the first surface and all The preset area 602 is in contact.

The preset area 602 is coated with a coating, and the material of the coating includes hot melt adhesive, and the viscosity of the coating is large enough to adhere the battery core 601 to the surface of the preset area 602, and prevent the battery cell 601 from slipping relative to the preset area 602 , thereby preventing the battery cell 601 from slipping and colliding with the battery packaging case 100 in the battery packaging case 100 , The battery cell 601 and the battery packaging case 100 are damaged.

The preset area 602 at least includes a first portion opposite to the area where the first foil layer 102 (shown in FIG. 1 ) is located, the first portion is not shown in FIG. 6 , and the area of the first portion is greater than or equal to the area of the first surface of the battery cell 601 .

When the battery cell 601 is assembled into the battery packaging case 100 , the first surface of the battery cell 601 is completely in contact with the first part of the predetermined area 602 , and the first part is in the battery cell 601 . The projection on the first surface of the battery cell 601 covers the first surface of the battery cell 601, therefore, the first surface of the battery cell 601 can be completely protected by the first foil layer 102, so as to obtain better protection. , reducing the possibility of damage to the battery 600 .

The battery cell 601 is hexahedral, the shape of the battery packaging case 100 matches the shape of the battery cell 601 , and is also a hexahedral packaging case, as shown in FIG. 1 , and the size of the battery packaging case 100 is larger than The size of the battery cell 601 is to wrap the battery cell 601 inside. Since the middle area of each wall is the area where the battery 600 is most easily impacted, the first foil layer 102 is provided in the middle area of each wall to prevent the battery 600 from being dropped, collided, etc. The middle area of the battery 600 is damaged, resulting in damage to the battery 600 and affecting the service life of the battery 600 .

And since the battery 600 is easily knocked against the corner of the battery 600 packaging case when it falls, the first foil layer 102 is distributed at the corner of the battery packaging case 100 to effectively protect the battery packaging. The corners of the case 100 prevent the corners of the battery packaging case 100 from being damaged when the battery packaging case 100 is dropped.

The first wall 105 (as shown in FIG. 1 ) of the battery 600 packaging case can take one edge as an axis, and rotate around the axis. When packaging the battery 600 , the first wall 105 is lifted up, the battery cell 601 is assembled into the battery packaging case 100 , and the first wall 105 is sealed to the other walls 101 . The encapsulation is completed at the opening of the enclosed unclosed receiving area.

The other side of the first wall 105 opposite to the side where the shaft is located forms a top seal, and the tabs of the battery cells 601 will protrude from the top seal. The strips form side seals. Both the top seal and the side seal belong to the edge sealing region 104 (as shown in FIG. 1 ). In the process of preparing the edge sealing area 104 of the battery packaging case 100 , the foil for constructing the battery packaging case 100 needs to be bent, therefore, a second foil with lower hardness is distributed in the edge sealing area 104 Layer 102 to accommodate bending requirements.

In the embodiment shown in FIG. 6 , the density of the second foil layer 103 (shown in FIG. 1 ) is lower than the density of the first foil layer 102 to reduce the overall weight of the battery 600 .

A first material layer 301 (as shown in FIG. 3 ) is disposed between the first foil layer 102 and the second foil layer 103 , and the material of the first material layer 301 includes polypropylene material or polyacrylated material At least one of them has a certain buffering effect, which can buffer the stress between the first foil layer 102 and the second foil layer 103 and has an impact resistance effect. When the battery 600 is dropped, a part of the impact can be absorbed to prevent the battery packaging case 100 of the battery 600 from being damaged.

The battery packaging case 100 and the battery of the present application use the first foil layer 102 and the second foil layer 103 with a hardness difference of at least HB300, so the minimum hardness of the first foil layer 102 is HB300, which can effectively improve the composite foil, battery The hardness of the packaging case and the battery reduces the probability of damage to the battery, and because the hardness of the second foil layer 103 is low, the processing difficulty of the battery packaging case 100 can also be simplified.

The above descriptions are only the embodiments of the present application, and are not intended to limit the scope of the patent of the present application. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present application, such as the interaction of technical features between the embodiments Combination, or direct or indirect application in other related technical fields, are equally included in the scope of patent protection of this application.

Claims

A battery packaging case, comprising:

A plurality of walls are formed to enclose an accommodating space, and different regions of the walls are distributed with a first foil layer and a second foil layer, the hardness of the first foil layer is greater than that of the second foil layer, and the The difference in hardness between the first foil layer and the second foil layer is greater than or equal to HB300.
The battery packaging case according to claim 1, wherein the number of the walls is at least 4, and the walls are connected by edges to enclose the enclosed accommodating space, and the middle area of the walls is distributed with the first accommodating space. a foil layer, and/or,

The first foil layer is distributed at the intersection of any three or more of the walls.
The battery packaging case of claim 1, further comprising: a safety valve mounted on the first surface of the wall and penetrating the wall in a direction perpendicular to the first surface of the wall.
The battery packaging case of claim 1, wherein the density of the second foil layer is lower than the density of the first foil layer.
The battery packaging case according to claim 1, wherein a first material layer is disposed between the first foil layer and the second foil layer, and the material of the first material layer comprises polypropylene material or polyacrylic acid at least one of the chemical materials.
The battery packaging case according to claim 1, further comprising a base material, the first surface of the base material is disposed toward the outside of the battery packaging case, and both the first foil layer and the second foil layer are formed on the first surface of the substrate.
The battery packaging case according to claim 6, wherein the first foil layer includes at least one of a stainless steel layer, a titanium alloy layer, and an aluminum alloy layer, the second foil layer includes an aluminum layer, and the The substrate includes a polypropylene layer.
The battery packaging case according to claim 6, further comprising: a second material layer located at least between the first foil layer and the base material, and at least between the second foil layer and the substrate. Between the substrates, the viscosity of the second material layer is greater than a preset value.
The battery packaging case according to claim 1, wherein a third material layer is formed on the first surface of the second foil layer, and the material of the third material layer comprises at least one of nylon material or resin material kind.
The battery packaging case according to claim 9, wherein the thickness of the first foil layer is greater than the thickness of the second foil layer, and the third material layer is located on the same side of the battery packaging case. A surface is flush with the first surface of the first foil layer.
A battery, characterized in that, comprising:

The battery packaging case described in claim 1;

The battery core is arranged in the battery packaging case.
The battery according to claim 11, wherein the battery packaging case is a hexahedral packaging case, and the first foil layer is distributed in the middle region of each wall of the hexahedral packaging case.
The battery according to claim 12, wherein the first foil layer is distributed at the corners of the hexahedral packaging shell;

The hexahedral packaging shell includes a first wall, and the intersection of the first wall and other walls is an edge sealing area, and the second foil layer is distributed in the edge sealing area.
13. The battery of claim 12, wherein the density of the second foil layer is less than the density of the first foil layer.
The battery according to claim 12, wherein a first material layer is disposed between the first foil layer and the second foil layer, and the material of the first material layer comprises polypropylene material or polyacrylic acid at least one of the chemical materials.