Casing, battery cell, battery and electrical device

Abstract

The present application provides a shell, a battery cell, a battery and an electrical device, wherein the shell includes: a main body, and a thickened portion, which is interconnected with the main body, and the thickened portion is arranged at the opening of the shell, and the wall thickness of at least part of the thickened portion is greater than the wall thickness of the main body; wherein the thickened portion is provided with a support portion, and the support portion is used to support the cover body that closes the opening. In the embodiment of the present application, by setting a thickened portion on the shell, on the one hand, the size of the support portion can be reasonably set to ensure the support effect on the cover body. On the other hand, even if the shell is grooved to form a support portion in order to support the cover body that is closed at the opening, the remaining size of the thickened portion after the support portion is set can still be large, which can improve the structural strength of the shell and thus improve the deformation problem of the shell. On the other hand, since the remaining size of the thickened portion after the support portion is set is still large, when the cover body is welded to the thickened portion after the support portion is set, the welding strength of the shell and the cover body can be enhanced.

Description

Technical Field

[0001] The present application relates to the field of batteries, and in particular to a housing, a battery cell, a battery and an electrical device. Background Art

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages in energy conservation and environmental protection. For electric vehicles, battery technology is an important factor in their development.

[0003] In the existing battery manufacturing process, the shell of the battery cell supports the cover, which may result in insufficient structural strength of the shell of the battery cell and the shell is prone to deformation. Summary of the invention

[0004] In view of the above problems, the present application provides a housing, a battery cell, a battery and an electrical device, which can alleviate the deformation problem caused by insufficient strength of the housing structure.

[0005] In the first aspect, the present application provides a shell, comprising: a main body portion, and a thickened portion, which is interconnected with the main body portion, and the thickened portion is arranged at the opening of the shell, and the wall thickness of at least part of the thickened portion is greater than the wall thickness of the main body portion; wherein the thickened portion is provided with a supporting portion, and the supporting portion is used to support a cover body that closes the opening.

[0006] In the technical solution of the embodiment of the present application, on the one hand, the size of the support portion can be reasonably set to ensure the support effect on the cover body. On the other hand, even if the shell is grooved to form a support portion in order to support the cover body that is closed at the opening, the remaining size of the thickened portion after the support portion is set can still be large, which can improve the structural strength of the shell and thus improve the deformation problem of the shell. On the other hand, since the remaining size of the thickened portion after the support portion is set is still large, when the cover body is welded to the thickened portion after the support portion is set, the welding strength of the shell and the cover body can be enhanced. In some embodiments, the thickened portion includes a first part and a second part, the first part is located between the second part and the main body, and the wall thickness of the second part is less than the wall thickness of the first part to form a support portion. By making the thickness of the second part less than the wall thickness of the first part, a stepped support portion can be formed between the first part and the second part, thereby providing support to the cover body.

[0007] In some embodiments, the support portion is located inside the shell. The edge of the cover body overlaps the support portion inside the shell, and the cover body and the shell can be welded from the upper side of the cover body, which is convenient for operation.

[0008] In some embodiments, the support portion includes a support surface for supporting the cover body, and the extension dimension of the support surface along the thickness direction of the main body portion is 0.05 mm to 2 mm. When the extension dimension of the support surface is within the above range, it can avoid that the size of the support surface is too small, resulting in insufficient support capacity and difficulty in supporting the cover body; it can also avoid that the size of the support surface is too large, affecting the structural strength of the shell.

[0009] In some embodiments, the outer surface of the first part and the outer surface of the second part are arranged on the same plane. On the one hand, the shape of the shell can be simplified, which is convenient for the preparation and molding of the shell; on the other hand, the protrusions on the outer surface of the shell can be reduced, which improves the problem that the shell is easily deformed by bumps.

[0010] In some embodiments, the outer surface of the main body is recessed toward the inside of the shell relative to the outer surface of the thickened portion. By thickening the shell opening on the outer side of the shell to form the thickened portion, the manufacturing and molding of the shell is facilitated.

[0011] In some embodiments, the thickened portion and the main body are connected by a first transition portion, and the wall thickness of the first transition portion gradually increases along the direction from the main body to the thickened portion. By providing a first transition portion with gradually increasing thickness, the stress concentration problem caused by the sudden change in the shell wall thickness can be improved, and the scratch problem caused by the large-sized edges and corners formed on the outer surface of the shell can be improved.

[0012] In some embodiments, the inner surface of the main body, the inner surface of the first transition portion, and the inner surface of the second portion are coplanar, so as to ensure the flatness of the inner surface of the shell, so that there is enough space in the shell for arranging the electrode assembly.

[0013] In some embodiments, the extension dimension of the first transition portion in the direction from the main body to the thickened portion is 2 mm to 20 mm. This can improve the stress concentration problem caused by the sudden change in the shell wall thickness due to the first transition portion extending too small, and can also improve the waste of materials for preparing the first transition portion due to the first transition portion extending too large. In some embodiments, the wall thickness of the first part is 0.6 mm to 1.2 mm. When the wall thickness of the first part is within the above range, it can avoid deformation due to insufficient shell strength caused by insufficient wall thickness of the first part, and can also avoid stress concentration caused by excessive difference in wall thickness between the first part and the main body due to excessive wall thickness of the first part, which affects the structural strength of the shell.

[0014] In some embodiments, the wall thickness of the second part is 0.4 mm to 1.0 mm. When the wall thickness of the second part is within the above range, it can avoid the second part being too thin, resulting in insufficient welding strength between the second part and the cover body, and it can also avoid the second part being too thick, resulting in waste of preparation materials.

[0015] In some embodiments, the wall thickness of the body is 0.5 mm to 1.0 mm. When the wall thickness of the body is within the above range, it can avoid deformation of the shell due to insufficient wall thickness of the body and also avoid affecting the energy density due to excessive wall thickness of the body.

[0016] In some embodiments, the ratio of the wall thickness of the first part to the wall thickness of the main body is 1 to 1.5. When the wall thickness of the first part and the wall thickness of the main body meet the above ratio, it can avoid deformation of the shell due to insufficient strength caused by insufficient wall thickness of the first part, and it can also avoid stress concentration caused by excessive difference in wall thickness between the first part and the main body due to excessive wall thickness of the first part, which affects the structural strength of the shell.

[0017] In some embodiments, the total extension dimension of the thickened portion in the direction from the main body to the thickened portion is 2 mm to 12 mm. When the total extension dimension of the thickened portion in the direction from the main body to the thickened portion is within the above range, it can avoid the size of the thickened portion being too small and not providing enough space to set the support portion. When the shell is used for a battery cell, it can also avoid the size of the thickened portion being too large, which affects the energy density of the battery cell.

[0018] In some embodiments, the housing includes a plurality of side panels connected to each other, and the main body, the thickened portion and the support portion are provided on at least one side panel. When the housing includes a plurality of side panels, at least one of the side panels is provided with a thickened portion, which can provide support to the cover body through the support portion and can also improve the housing deformation problem caused by insufficient housing.

[0019] In some embodiments, the multiple side panels include a first side panel and a second side panel that are interconnected, the main body portion, the thickened portion, and the support portion are arranged on the first side panel, and the second side panel includes a first plate portion and a second plate portion located on the side of the first plate portion facing the opening, and the thickness of the first plate portion is less than the thickness of the second plate portion.

[0020] In these embodiments, in the first side plate and the second side plate connected to each other, the first side plate is provided with a thickened portion to improve the structural strength of the first side plate. The second side plate is provided with a first plate portion and a second plate portion of different thicknesses, the first plate portion is thinner to save preparation materials, and the second plate portion is provided close to the opening to improve the structural strength of the shell at the opening position, thereby making the shell less likely to deform.

[0021] In some embodiments, the inner surface of the first plate portion is recessed toward the outside of the shell relative to the inner surface of the second plate portion. When the shell is used in a battery cell and contains an electrode assembly, the first plate portion is disposed away from the opening, the first plate portion is disposed close to the position where the electrode assembly is disposed, and the first plate portion is recessed toward the outside of the shell to leave sufficient space for the electrode assembly to thereby increase the energy density of the battery cell.

[0022] In some embodiments, the outer surface of the first plate portion and the outer surface of the second plate portion are coplanar, which can improve the flatness of the outer surface of the shell. When the shell is used for a battery cell, the shell can be adjacently arranged through the second side plate, which can reduce the distance between two adjacent battery cells and reduce the total space size occupied by multiple battery cells.

[0023] In some embodiments, the area of ​​the first side plate is smaller than that of the second side plate, that is, the thickened portion and the support portion are arranged on the first side plate with a smaller area, so that when the housing is used for battery cells, two adjacent battery cells can face each other through the side plate with a larger area.

[0024] In some embodiments, the first plate portion and the second plate portion are connected by a second transition portion, and the wall thickness of the second transition portion gradually increases in the direction from the first plate portion to the second plate portion. By providing the second transition portion, the stress concentration caused by the sudden change in thickness between the first plate portion and the second plate portion can be improved. At the same time, it can also improve the problem that the sudden change in thickness between the first plate portion and the second plate portion has large edges and corners, making the shell easily scratched or the shell easily scratches the electrode assembly located therein.

[0025] In some embodiments, the second plate portion extends from the first plate portion to the second plate portion by 2 to 10 mm, which can improve the structural strength of the housing due to insufficient size of the second plate portion and the energy density of the battery cell due to excessive size of the second plate portion.

[0026] In some embodiments, the extension dimension of the second transition portion in the direction from the first plate portion to the second plate portion is 1.5 mm to 20 mm, which can improve the thickness mutation between the first plate portion and the second plate portion due to the insufficient dimension of the second transition portion, and can also improve the energy density of the battery cell affected by the excessive dimension of the second transition portion.

[0027] In some embodiments, the wall thickness of the second plate portion is 0.4 mm to 1.0 mm, and / or the wall thickness of the first plate portion is 0.3 mm to 1.0 mm. When the wall thickness of the second plate portion and / or the first plate portion is within the above range, it can improve the insufficient strength of the shell structure caused by insufficient thickness of the second plate portion and / or the first plate portion, and can also improve the energy density of the battery cell affected by the excessive thickness of the second plate portion and / or the first plate portion.

[0028] In some embodiments, the difference in wall thickness between the second plate portion and the first plate portion is 0.1 mm to 0.5 mm, and / or the ratio of the wall thickness between the second plate portion and the first plate portion is 1 to 1.5. This can improve the problem of stress concentration caused by the excessive difference in thickness between the first plate portion and the second plate portion, and can also improve the problem of insufficient strength of the shell caused by the excessive difference in thickness between the first plate portion and the second plate portion.

[0029] In a second aspect, an embodiment of the present application further provides a battery cell, comprising: a cover body; and a shell according to any one of the above-mentioned embodiments of the first aspect, wherein a support portion of the shell supports the cover body.

[0030] In some embodiments, the housing includes a first side plate and a second side plate which are arranged circumferentially around the opening and connected to each other, the body portion, the thickened portion and the support portion are arranged on the first side plate, the second side plate includes a first plate portion and a second plate portion which is located on a side of the first plate portion facing the opening, and the thickness of the first plate portion is less than the thickness of the second plate portion;

[0031] The battery cell further includes an electrode assembly located in the housing, and in a direction perpendicular to the second side plate, projections of the electrode assembly and the second plate portion do not overlap.

[0032] In these embodiments, by making the projections of the electrode assembly and the second plate portion non-overlap, the thickened second plate portion and the electrode assembly are offset, and the second plate portion does not interfere with the electrode assembly.

[0033] In a third aspect, an embodiment of the present application further provides a battery, comprising a housing and a battery cell provided by any one of the embodiments of the second aspect, wherein the battery cell is accommodated in the housing.

[0034] In a fourth aspect, an embodiment of the present application further provides an electrical device, comprising a battery cell provided by any of the above-mentioned embodiments of the second aspect, wherein the battery cell is used to provide electrical energy.

[0035] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0037] Figure 1 is a structural schematic diagram of a vehicle provided by an embodiment of the present application;

[0038] Figure 2 is a schematic diagram of the structure of a battery provided in one embodiment of the present application;

[0039] Figure 3 is a schematic structural diagram of a battery provided in another embodiment of the application;

[0040] Figure 4is a structural schematic diagram of a battery module provided by an embodiment of the present application;

[0041] Figure 5 is a structural schematic diagram of a battery module provided by another embodiment of the present application;

[0042] Figure 6 is a schematic diagram of the exploded structure of a battery cell provided in one embodiment of the present application;

[0043] Figure 7 is a schematic diagram of an exploded structure of a battery cell provided in another embodiment of the present application;

[0044] Figure 8 It is a structural schematic diagram of a housing provided in one embodiment of the present application;

[0045] Fig. 9 yes Figure 8 A cross-sectional view taken along line M in FIG.

[0046] Fig.10 is a cross-sectional view in the width direction of the housing after the electrode assembly is accommodated in the housing;

[0047] Fig.11 is a structural schematic diagram of a housing provided by another embodiment of the present application;

[0048] Fig.12 yes Fig. 9 A schematic diagram of the local enlarged structure at position I in the middle;

[0049] Fig.13 yes Fig.10 Schematic diagram of the local enlarged structure at II in the middle.

[0050] The reference numerals in the specific implementation manner are as follows:

[0051] 1 vehicle, 10 battery, 11 controller, 12 motor;

[0052] 20 battery module, 21 busbar component;

[0053] 30 box body, 301 first box body part, 302 second box body part;

[0054] 40 battery cell, 41 cover, 411 electrode terminal, 42 shell, 42a first side plate, 42b second side plate, 421 body, 422 thickened portion, 422a first portion, 422b second portion, 423 support portion, 423a support surface, 424 first transition portion, 425 first plate portion, 426 second plate portion, 427 second transition portion, 428 accommodation space, 43 electrode assembly;

[0055] X is the first direction, Y is the second direction, and Z is the height direction. DETAILED DESCRIPTION

[0056] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0057] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present application should have the common meanings understood by technicians in the field to which the embodiments of the present application belong.

[0058] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0059] In addition, the technical terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0060] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0061] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0062] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0063] In the present application, the battery cell may include a lithium-ion secondary battery cell, a lithium-ion primary battery cell, a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell or a magnesium-ion battery cell, etc., and the embodiments of the present application do not limit this. The battery cell may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this.

[0064] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module or a battery pack. The battery generally includes a box for encapsulating one or more battery cells. The box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

[0065] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly includes a positive electrode sheet, a negative electrode sheet and a separator. A battery cell mainly works by the movement of metal ions between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector. The positive current collector includes a positive current collector and a positive electrode ear connected to the positive current collector. The positive current collector is coated with a positive active material layer, and the positive electrode ear is not coated with a positive active material layer. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material layer includes a positive active material. The positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. The negative electrode sheet includes a negative current collector and a negative active material layer, the negative active material layer is coated on the surface of the negative current collector; the negative current collector includes a negative current collector and a negative electrode tab connected to the negative current collector, the negative current collector is coated with the negative active material layer, and the negative electrode tab is not coated with the negative active material layer. The material of the negative current collector can be copper, the negative active material layer includes a negative active material, and the negative active material can be carbon or silicon, etc. The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.

[0066] The inventors of the present invention have noticed that in a battery cell, the battery cell includes a shell and a cover body covering the opening of the shell. In order to allow the cover body to better cover the shell, a groove is provided at the opening of the shell to provide a limit for the cover body. This results in insufficient structural strength at the opening of the shell, making the shell prone to deformation.

[0067] In order to alleviate the problem of deformation caused by insufficient shell strength, the applicant has found that the shell can be partially or completely thickened at the opening position to improve the structural strength of the shell.

[0068] Based on the above considerations, in order to solve the problem of easy deformation caused by insufficient strength of the battery cell shell, the inventor has designed a battery cell shell after in-depth research. In such a shell, the shell includes a main body and a thickened part, the thickened part is located on the side of the main body facing the shell opening, and the wall thickness of the thickened part is greater than the wall thickness of the main body, and a support part for supporting the cover is provided on the thickened part.

[0069] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using batteries.

[0070] The electrical device may be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, and the like; the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, and the like; the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, and the like; the electric tool may include a metal cutting electric tool, a grinding electric tool, an assembly electric tool, and an electric tool for railways, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator, and an electric planer, and the like. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0071] It should be understood that the technical solutions described in the embodiments of the present application are not limited to the batteries and electrical equipment described above, but can also be applied to all batteries including a box and electrical equipment using the battery. However, for the sake of simplicity, the following embodiments are described using electric vehicles as an example.

[0072] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1 provided for some embodiments of the present application. The vehicle 1 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 10 is provided inside the vehicle 1, and the battery 10 may be provided at the bottom, the head or the tail of the vehicle 1. The battery 10 may be used to power the vehicle 1, for example, the battery 10 may be used as an operating power source for the vehicle 1. The vehicle 1 may also include a controller 11 and a motor 12, and the controller 11 is used to control the battery 10 to power the motor 12, for example, for the starting, navigation and working power requirements of the vehicle 1 during driving.

[0073] In some embodiments of the present application, the battery 10 can be used not only as an operating power source for the vehicle 1 , but also as a driving power source for the vehicle 1 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1 .

[0074] In order to meet different power requirements, the battery 10 may include a plurality of battery cells, which refers to the smallest unit that constitutes a battery module or a battery pack. A plurality of battery cells can be connected in series and / or in parallel via electrode terminals for use in various applications. The battery mentioned in the present application includes a battery module or a battery pack. Among them, a plurality of battery cells can be connected in series, in parallel, or in mixed connection, where mixed connection refers to a mixture of series and parallel connection. In the embodiment of the present application, a plurality of battery cells can directly constitute a battery pack, or they can first constitute a battery module 20, and the battery module 20 can then constitute a battery pack.

[0075] See also Figure 2and Figure 3 , Figure 2 A schematic structural diagram of a battery 10 according to an embodiment of the present application is shown. Figure 3 A schematic structural diagram of a battery 10 according to another embodiment of the present application is shown. Figure 2 and Figure 3 The difference is Figure 2 The battery cell 40 in the embodiment is a square battery cell 40. Figure 3 The battery cell 40 in FIG. 4 is a cylindrical battery cell 40 .

[0076] like Figure 2 and Figure 3 As shown, the battery 10 includes a case 30 and a battery cell 40 , wherein the battery cell 40 is accommodated in the case 30 .

[0077] The box 30 can be a simple three-dimensional structure such as a single cuboid, cylinder or sphere, or a complex three-dimensional structure composed of simple three-dimensional structures such as cuboids, cylinders or spheres, which is not limited in the present embodiment. The box 30 can be made of alloy materials such as aluminum alloy, iron alloy, polymer materials such as polycarbonate, polyisocyanurate foam plastic, or composite materials such as glass fiber and epoxy resin, which is not limited in the present embodiment.

[0078] The box 30 is used to accommodate the battery cell 40, and the box 30 can be a variety of structures. In some embodiments, the box 30 may include a first box portion 301 and a second box portion 302, the first box portion 301 and the second box portion 302 cover each other, and the first box portion 301 and the second box portion 302 jointly define a receiving cavity for accommodating the battery cell 40. The second box portion 302 may be a hollow structure with one end open, the first box portion 301 is a plate-like structure, and the first box portion 301 covers the open side of the second box portion 302 to form a box 30 with a receiving cavity; the first box portion 301 and the second box portion 302 may also be a hollow structure with one side open, and the open side of the first box portion 301 covers the open side of the second box portion 302 to form a box 30 with a receiving cavity. Of course, the first box portion 301 and the second box portion 302 may be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0079] In order to improve the sealing performance after the first box body 301 and the second box body 302 are connected, a sealing member, such as a sealant, a sealing ring, etc., may also be provided between the first box body 301 and the second box body 302 .

[0080] Assuming that the first box body portion 301 covers the top of the second box body portion 302 , the first box body portion 301 can also be referred to as an upper box cover, and the second box body portion 302 can also be referred to as a lower box body 30 .

[0081] In the battery, there can be one or more battery cells 40. If there are more than one battery cell 40, the battery cells 40 can be connected in series, in parallel, or in mixed connection. Mixed connection means that the battery cells 40 are both connected in series and in parallel. The battery cells 40 can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the battery cells 40 can be accommodated in the box 30; of course, the battery modules 20 can also be formed by connecting the battery cells 40 in series, in parallel, or in mixed connection, and then the battery modules 20 can be formed into a whole by connecting the battery cells 40 in series, in parallel, or in mixed connection, and then accommodated in the box 30.

[0082] See also Figure 4 and Figure 5 , Figure 4 A schematic structural diagram of a battery module 20 according to an embodiment of the present application is shown. Figure 5 A schematic structural diagram of a battery module 20 provided in another embodiment of the present application is shown. Figure 4 and Figure 5 The difference is that Figure 4 The battery module 20 is formed by combining square battery cells 40. Figure 5 The battery module 20 is formed by combining cylindrical battery cells 40 .

[0083] In some embodiments, Figure 4 and Figure 5 As shown, there are multiple battery cells 40, and the multiple battery cells 40 are first connected in series, in parallel, or in mixed series to form a battery module 20. The multiple battery modules 20 are then connected in series, in parallel, or in mixed series to form a whole, and are accommodated in a box.

[0084] The multiple battery cells 40 in the battery module 20 can be electrically connected through the busbar component 21 to achieve parallel connection, series connection or mixed connection of the multiple battery cells 40 in the battery module.

[0085] In the present application, the battery cell 40 may include a lithium-ion battery cell, a sodium-ion battery cell or a magnesium-ion battery cell, etc., and the embodiments of the present application do not limit this. The battery cell 40 may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this. The battery cell 40 is generally divided into three types according to the packaging method: cylindrical battery cells, square battery cells and soft-pack battery cells, and the embodiments of the present application do not limit this. However, for the sake of simplicity, the following embodiments are all described using square battery cells and cylindrical battery cells as examples.

[0086] See also Figure 6 and Figure 7 , Figure 6 A schematic diagram of the exploded structure of a battery cell 40 provided in some embodiments of the present application. Figure 7 Schematic diagram of the exploded structure of a battery cell 40 provided in some other embodiments of the present application. Figure 6 and Figure 7 The difference is that Figure 6 The figure is a schematic diagram of the exploded structure of a square battery cell 40. Figure 7 It is a schematic diagram of the exploded structure of a cylindrical battery cell 40.

[0087] like Figure 6 and Figure 7 As shown, the battery cell 40 refers to the smallest unit constituting the battery and includes a cover 41 , a housing 42 and an electrode assembly 43 .

[0088] The cover 41 refers to a component that covers the opening of the shell 42 to isolate the internal environment of the battery cell 40 from the external environment. Without limitation, the shape of the cover 41 can be adapted to the shape of the shell 42 to match the shell 42. Optionally, the cover 41 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the cover 41 is not easily deformed when squeezed and collided, so that the battery cell 40 can have a higher structural strength and the safety performance can also be improved. Functional components such as electrode terminals 411 can be provided on the cover 41. The electrode terminal 411 can be used to electrically connect to the electrode assembly 43 for outputting or inputting electrical energy of the battery cell 40. In some embodiments, the cover 41 can also be provided with a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 40 reaches a threshold. The material of the cover 41 can also be a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this. In some embodiments, an insulating member may be provided inside the cover 41 to isolate the electrical connection components in the housing 42 from the cover 41 to reduce the risk of short circuit. For example, the insulating member may be plastic, rubber, or the like.

[0089] The shell 42 is a component used to cooperate with the cover 41 to form the internal environment of the battery cell 40, wherein the formed internal environment can be used to accommodate the electrode assembly 43, the electrolyte (not shown in the figure) and other components. The shell 42 and the cover 41 can be independent components, and an opening can be set on the shell 42, and the internal environment of the battery cell 40 is formed by covering the opening with the cover 41 at the opening. Without limitation, the cover 41 and the shell 42 can also be integrated. Specifically, the cover 41 and the shell 42 can form a common connection surface before other components are put into the shell, and when the interior of the shell 42 needs to be encapsulated, the cover 41 covers the shell 42. The shell 42 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 42 can be determined according to the specific shape and size of the electrode assembly 43. The material of the shell 42 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0090] The electrode assembly 43 is a component in the battery cell 40 where an electrochemical reaction occurs. One or more electrode assemblies 43 may be contained in the housing 42. The electrode assembly 43 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The portion of the positive electrode sheet and the negative electrode sheet with active materials constitutes the main body of the electrode assembly 43, and the portion of the positive electrode sheet and the negative electrode sheet without active materials each constitutes a pole ear (not shown in the figure). The positive pole ear and the negative pole ear may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the pole ear connects the electrode terminal 411 to form a current loop.

[0091] See also Figures 8 to 10 , Figure 8 is a schematic diagram of the structure of the housing 42 provided in some embodiments of the present application, Fig. 9 yes Figure 8 A partial cross-sectional view taken along line M in FIG. Fig. 9 The area below the mid-P line was not dissected. Fig.10 It is a cross-sectional view in the width direction of the case after the electrode assembly is accommodated in the case.

[0092] Please continue reading Fig.11 , Fig.11 is a schematic diagram of the structure of the housing 42 provided in some other embodiments of the present application, Figure 8 and Fig.11 The difference is that Figure 8 Schematic diagram of the structure of the housing 42 for a square battery cell. Fig.11 Schematic diagram of the structure of the housing 42 for a cylindrical battery cell.

[0093] Please continue reading Fig.12 and Fig.13 , Fig.12 yes Fig. 9 The local enlarged structural diagram at I in the middle, Fig.13 yes Fig.10 Schematic diagram of the local enlarged structure at II in the middle.

[0094] like Figures 8 to 13 As shown, the shell 42 provided in the embodiment of the present application includes a main body portion 421 and a thickened portion 422, the thickened portion 422 and the main body portion 421 are connected to each other, and the thickened portion 422 is arranged at the opening of the shell 42, and the wall thickness of at least part of the thickened portion 422 is greater than the wall thickness of the main body portion 421; wherein the thickened portion 422 is provided with a supporting portion 423, and the supporting portion 423 is used to support the cover body 41 that closes the opening.

[0095] When the housing 42 is used for a square battery cell, the housing 42 is a square shell, and the housing 42 includes four side walls and a bottom wall. The side walls of the housing 42 include a plurality of side panels connected to each other, and the body 421 of the housing 42 can be a part of one of the side panels. The thickened portion 422 is a part of the side panel close to the opening, that is, the body 421 and the thickened portion 422 constitute a side panel of the housing 42. The support portion 423 is a part of the housing 42 used to support the cover 41.

[0096] When the housing 42 is used for a cylindrical battery cell, the housing 42 includes a cylindrical side wall and a bottom wall.

[0097] The body part 421 may be a large part of the side wall, and is used to surround the electrode assembly 43 in the circumferential direction, and the body part 421 is a circumferentially closed cylindrical shape. The thickened part 422 is a side wall thickened part 422 close to the opening on the body part 421, and may also be a circumferentially closed cylindrical shape. The support part 423 is a part of the thickened part 422 used to support the cover body 41. The support part 423 may be arranged in an annular shape or multiple support parts 423 may be arranged at intervals along the circumference of the shell 42.

[0098] Alternatively, the body portion 421 may be a part of the cylindrical side wall in the circumferential direction, that is, the cylindrical side wall is composed of a plurality of arc-shaped plates, the body portion 421 is a part of one of the arc-shaped plates, and the body portion 421 is a non-enclosed arc-shaped plate. At least one arc-shaped plate includes a body portion 421, a thickened portion 422 disposed on the side of the body portion 421 facing the opening, and a support portion 423 disposed on the thickened portion 422, and at least one arc-shaped plate is not provided with a thickened portion 422.

[0099] In the technical solution of the embodiment of the present application, the shell 42 includes a main body 421 and a thickened portion 422, and a support portion 423 for supporting the shell 42 is arranged on the thickened portion 422. The wall thickness of the thickened portion 422 is greater than the thickness of the main body 421. On the one hand, the size of the support portion 423 can be reasonably set to ensure the support effect on the cover body. On the other hand, even if the shell 42 is grooved to form the support portion 423 in order to support the cover body closed at the opening, the remaining size of the thickened portion 422 after the support portion 423 is set can still be large, which can improve the structural strength of the shell 42 and thus improve the deformation problem of the shell 42. On the other hand, since the remaining size of the thickened portion 422 is still large after the support portion 423 is set, when the cover body is welded to the thickened portion 422 after the support portion 423 is set, the welding strength of the shell 42 and the cover body 41 can be enhanced.

[0100] There are many ways to connect the main body 421 and the thickened portion 422, such as welding the main body 421 and the thickened portion 422. Alternatively, the main body 421 and the thickened portion 422 are integrally formed to improve the connection strength between the main body 421 and the thickened portion 422.

[0101] The housing 42 includes a receiving space 428, and the opening is in communication with the receiving space 428. When the housing 42 is used for a battery cell, and the battery cell includes an electrode assembly, the electrode assembly can be disposed in the receiving space 428 through the opening.

[0102] The thickened portion 422 is disposed at the opening of the shell 42 which means that the thickened portion 422 is disposed closer to the opening of the shell 42 than the main body portion 421 , that is, the thickened portion 422 is located on the side of the main body portion 421 facing the opening.

[0103] According to some embodiments of this application, please continue to refer to Fig.12 The thickened portion 422 includes a first portion 422a and a second portion 422b, wherein the first portion 422a is located at a side of the second portion 422b away from the opening, and the wall thickness of the second portion 422b is smaller than that of the first portion 422a to form a support portion 423. The first portion 422a is located at a side of the second portion 422b away from the opening, so the second portion 422b is disposed closer to the opening.

[0104] In these embodiments, by making the thickness of the second portion 422b smaller than the wall thickness of the first portion 422a, a stepped support portion 423 can be formed between the first portion 422a and the second portion 422b, thereby enabling the support portion 423 to provide support to the cover body 41.

[0105] When the cover is closed on the opening, the shape of the cover can be set in various ways, or the cover includes a closing portion and a wall portion connected to the surrounding side of the closing portion, and the wall portion is extended and formed along the thickness direction of the closing portion. When the cover is closed on the opening of the shell 42, the wall portion overlaps the support portion 423.

[0106] The support portion 423 may be disposed at various positions. For example, the support portion 423 may be located outside the shell 42 , so that the cover body including the covering portion and the wall portion may be overlapped with the support portion 423 through the wall portion.

[0107] Alternatively, according to some embodiments of the present application, please continue to refer to Fig.12 , the support portion 423 is located inside the shell 42. In these embodiments, the edge of the cover body overlaps the support portion 423 inside the shell 42, and the cover body and the shell can be welded from the upper side of the cover body, which is convenient for operation.

[0108] According to some embodiments of this application, please continue to refer to Fig.12The support portion 423 includes a support surface 423a for supporting the cover body 41, and the extension dimension T6 of the support surface 423a along the circumferential direction of the opening is 0.05mm to 2mm. When the extension dimension T6 of the support surface 423a in the circumferential direction of the opening is within the above range, it can avoid that the extension dimension T6 of the support surface 423a is too small to cause insufficient support capacity and difficulty in supporting the cover body; it can also avoid that the extension dimension T6 of the support surface 423a is too large to affect the structural strength of the shell 42.

[0109] Optional, such as Figures 8 to 10 As shown, when the housing 42 is used for a square battery cell 40, the housing 42 includes a first side plate 42a and a second side plate 42b connected to each other, the two first side plates 42a are arranged opposite to each other along a first direction X, the two second side plates 42b are arranged opposite to each other along a second direction Y, and the opening circumference includes the first direction X and / or the second direction Y. For example, the support portion 423 is arranged on the first side plate 42a, and the opening circumference is a direction perpendicular to the first side plate 42a, that is, the first direction X. When the support portion 423 is arranged on the second side plate 42b, the opening circumference is a direction perpendicular to the second side plate 42b, that is, the second direction Y.

[0110] Optional, such as Fig.11 As shown, when the housing 42 is used for a cylindrical battery cell 40 , the circumferential direction of the opening is the circumferential direction of the housing 42 .

[0111] According to some embodiments of the present application, Fig.12 As shown, the outer surface of the first part 422a and the outer surface of the second part 422b are arranged on the same plane. On the one hand, the shape of the shell 42 can be simplified, which is convenient for the preparation and molding of the shell 42; on the other hand, the bulges on the outer surface of the shell 42 can be reduced, which improves the problem that the shell 42 is easily deformed by collision.

[0112] The outer surface of the first portion 422a refers to the surface of the first portion 422a that is away from the receiving space 428. Similarly, the outer surface of the second portion 422b refers to the surface of the second portion 422b that is away from the receiving space 428.

[0113] Optional, such as Figures 8 to 10 and Fig.12 As shown, when the housing 42 is used for a square battery cell, the outer surface of the first portion 422a may include a plane, the outer surface of the second portion 422b may also include a plane, and the outer surface of the first portion 422a and the outer surface of the second portion 422b are located in the same plane.

[0114] Optional, such as Fig.11 and Fig.12As shown, when the shell 42 is used for a cylindrical battery cell, the outer surface of the first part 422a is an arc-shaped surface, the outer surface of the second part 422b is an arc-shaped surface, and the outer surface of the first part 422a and the outer surface of the second part 422b are coplanar, that is, the curvature of the outer surface of the first part 422a is the same as the curvature of the outer surface of the second part 422b.

[0115] According to some embodiments of the present application, Fig.12 As shown, the outer surface of the main body 421 is recessed toward the inside of the shell 42 relative to the outer surface of the thickened portion 422 .

[0116] The outer surface of the main body 421 is the surface of the main body 421 away from the accommodation space 428, and the outer surface of the thickened portion 422 is the surface of the thickened portion 422 away from the accommodation space. The outer surface of the main body 421 is concave toward the inside of the shell 42 relative to the outer surface of the thickened portion 422, that is, the outer surface of the main body 421 is concave toward the direction close to the accommodation space relative to the outer surface of the thickened portion 422, and the outer surface of the main body 421 is located on the side of the outer surface of the thickened portion 422 facing the accommodation space.

[0117] In these embodiments, at least a portion of the thickened portion 422 is located on the outside of the main body 421 toward the shell 42. By thickening the outside of the shell 42 to form the thickened portion 422, the effect of the thickened portion 422 on the space inside the shell 42 can be improved. When the shell 42 is used for a battery cell and accommodates an electrode assembly, there is enough space inside the shell 42 for arranging the electrode assembly, thereby improving the effect of the thickened portion 422 on the energy density of the battery cell 40.

[0118] According to some embodiments of the present application, Fig.12 As shown, the thickened portion 422 and the main body portion 421 are connected via a first transition portion 424 , and the wall thickness of the first transition portion 424 gradually increases along the direction from the main body portion 421 to the thickened portion 422 .

[0119] In these embodiments, the direction from the main body 421 to the thickened portion 422 is along the height direction Z of the shell 42. By providing a first transition portion 424 with gradually increasing thickness, the stress concentration problem caused by the sudden change in the wall thickness of the shell 42 can be improved, and the problem of easy scratching caused by the large-sized edges and corners of the shell 42 can be improved.

[0120] There are many ways to connect the first transition portion 424 and the main body 421. The first transition portion 424 can be welded to the main body 421, or the first transition portion 424 can be integrally formed with the main body 421. Similarly, there are many ways to connect the first transition portion 424 and the thickened portion 422. The first transition portion 424 can be welded to the thickened portion 422, or the first transition portion 424 can be integrally formed with the thickened portion 422.

[0121] Optionally, the first transition portion 424 , the main body portion 421 and the thickened portion 422 are integrally formed, which can improve the stability of the interconnection between the first transition portion 424 and the main body portion 421 and the thickened portion 422 , and can simplify the preparation of the shell 42 .

[0122] According to some embodiments of the present application, Fig.12 As shown, the inner surface of the main body 421, the inner surface of the first transition portion 424 and the inner surface of the second portion 422b are coplanar.

[0123] In these embodiments, the inner surfaces of the main body 421 , the first transition portion 424 and the second portion 422 b are coplanar, which can ensure the flatness of the inner surface of the shell 42 , so that there is enough space in the shell 42 for arranging the electrode assembly.

[0124] The inner surface of the main body 421 refers to the surface of the main body 421 facing the accommodation space. The inner surface of the first transition portion 424 refers to the inner surface of the first transition portion 424 facing the accommodation space. The inner surface of the second portion 422b refers to the inner surface of the second portion 422b facing the accommodation space.

[0125] Optional, such as Figures 8 to 10 and Fig.12 As shown, when the shell 42 is used for a square battery cell, the inner surfaces of the main body 421, the first transition portion 424 and the second portion 422b are all planes, and the inner surfaces of the main body 421, the first transition portion 424 and the second portion 422b are located on the same surface.

[0126] Optional, such as Figure 11 to Figure 12 As shown, when the housing 42 is used for a cylindrical battery cell, the inner surfaces of the body 421 , the first transition portion 424 and the second portion 422 b are all arc-shaped surfaces, and the inner surfaces of the body 421 , the first transition portion 424 and the second portion 422 b have the same curvature.

[0127] According to some embodiments of the present application, Fig.12 As shown, an extension dimension H4 of the first transition portion 424 in the direction from the main body portion 421 to the thickened portion 422 is 2 mm to 20 mm.

[0128] In these embodiments, when the extension dimension H4 of the first transition portion 424 in the height direction Z is within the above range, it can improve the stress concentration problem caused by the sudden change in the wall thickness of the shell 42 due to the extension dimension H4 of the first transition portion 424 being too small, and it can also improve the waste of material in preparing the first transition portion 424 due to the extension dimension H4 of the first transition portion 424 being too large.

[0129] According to some embodiments of the present application, Fig.12 As shown, the wall thickness T4 of the first portion 422a is 0.6 mm to 1.2 mm.

[0130] In these embodiments, when the wall thickness T4 of the first part 422a is within the above range, it can prevent deformation of the shell 42 due to insufficient strength of the shell 42 caused by insufficient wall thickness T4 of the first part 422a, and it can also prevent stress concentration caused by excessive difference in wall thickness between the first part 422a and the main body 421 due to excessive wall thickness T4 of the first part 422a, thereby affecting the structural strength of the shell 42.

[0131] In some embodiments, Fig.12 As shown, the wall thickness T5 of the second part 422b is 0.4 mm to 1.0 mm. When the wall thickness T5 of the second part 422b is within the above range, it can avoid that the wall thickness T5 of the second part 422b is too small, resulting in insufficient welding strength between the second part 422b and the cover body when welding the two, and it can also avoid that the wall thickness T5 of the second part 422b is too large, resulting in waste of preparation materials.

[0132] According to some embodiments of the present application, Fig.12 As shown, the wall thickness T3 of the body 421 is 0.5 mm to 1.0 mm. When the wall thickness T3 of the body 421 is within the above range, it can avoid deformation of the shell 42 due to insufficient strength of the body 421 and also avoid excessive thickness T3 of the body 421 affecting the energy density.

[0133] According to some embodiments of the present application, Fig.12 As shown, the ratio of the wall thickness T4 of the first part 422a to the wall thickness T3 of the main body 421 is 1 to 1.5. When the wall thickness T4 of the first part 422a and the wall thickness T3 of the main body 421 meet the above ratio, it is possible to avoid deformation of the shell 42 due to insufficient strength of the insufficient wall thickness T4 of the first part 422a, and to avoid stress concentration caused by excessive difference in wall thickness between the first part 422a and the main body 421 due to excessive wall thickness T4 of the first part 422a, thereby affecting the structural strength of the shell 42.

[0134] According to some embodiments of the present application, Fig.12 As shown, an extension dimension H3 of the thickened portion 422 in the direction from the main body 421 to the thickened portion 422 is 2 mm to 12 mm.

[0135] In these embodiments, when the extension dimension H3 of the thickened portion 422 in the height direction Z is within the above range, it is possible to avoid the extension dimension H3 of the thickened portion 422 being too small and failing to provide sufficient space for setting the support portion 423; when the shell 42 is used for a battery cell, it is also possible to avoid the extension dimension H3 of the thickened portion 422 being too large and affecting the energy density of the battery cell.

[0136] According to some embodiments of the present application, the housing 42 includes a plurality of side panels connected to each other, and the main body 421, the thickened portion 422 and the support portion 423 are provided on at least one side panel. When the housing 42 includes a plurality of side panels, at least one of the side panels is provided with the thickened portion 422, which can provide support to the cover body through the support portion 423, and can also improve the deformation problem of the housing 42 caused by the insufficient housing 42.

[0137] Optional, such as Figures 8 to 10 As shown, when the housing 42 is used for a square-shaped battery cell 40 , the multiple side panels can be considered as side panels on the housing 42 located on different planes.

[0138] Or, as mentioned above, Fig.11 As shown, when the shell 42 is used for a cylindrical battery cell, the shell 42 can be a cylindrical shell, and the shell 42 can include a side wall arranged around the accommodating space 428. Optionally, the multiple side panels can be considered as side walls located at different positions of the shell 42 in the circumferential direction. For example, at least part of the side wall in the circumferential direction of the accommodating space 428 includes a body portion 421, a thickened portion 422, and a support portion 423. Further, the two opposite parts of the side wall include a body portion 421, a thickened portion 422, and a support portion 423, forming two oppositely arranged support portions 423, which can provide stable support to the cover 41.

[0139] According to some embodiments of the present application, Figures 8 to 13 As shown, multiple side panels include a first side panel 42a and a second side panel 42b that are interconnected, a main body portion 421, a thickened portion 422 and a support portion 423 are arranged on the first side panel 42a, and the second side panel 42b includes a first panel portion 425 and a second panel portion 426 located on the side of the first panel portion 425 facing the opening, and the thickness of the first panel portion 425 is less than the thickness of the second panel portion 426.

[0140] In these embodiments, in the first side plate 42a and the second side plate 42b connected to each other, the first side plate 42a is provided with a thickened portion 422 to improve the structural strength of the first side plate 42a. The second side plate 42b is provided with a first plate portion 425 and a second plate portion 426 of different thicknesses. The first plate portion 425 has a smaller thickness to save preparation materials, and the second plate portion 426 is provided close to the opening to improve the structural strength of the shell 42 at the opening position, thereby making the shell 42 less likely to deform.

[0141] Optional, such as Figures 8 to 10 As shown, when the housing 42 is used for a square battery cell, the first side plate 42a and the second side plate 42b can be considered as two side plates located in different planes and connected to each other.

[0142] Optional, such as Fig.11 As shown, when the housing 42 is used for a cylindrical battery cell, the first side plate 42 a and the second side plate 42 b may be portions of the side wall in different regions in the circumferential direction.

[0143] Optionally, the shell 42 includes two first side plates 42a relatively arranged along the first direction X, and the two first side plates 42a are both provided with a main body portion 421, a thickened portion 422 and a support portion 423, so that two support portions 423 relatively arranged along the first direction X can be formed, and the two support portions 423 can provide stable support to the cover body 41.

[0144] Optionally, the shell 42 includes two second side plates 42 b arranged opposite to each other along the second direction Y, and the two second side plates 42 b each include a first plate portion 425 and a second plate portion 426 , so as to save more materials and ensure that the shell 42 has sufficient structural strength.

[0145] Optionally, the two first side plates 42 a and the two second side plates 42 b are alternately arranged along the circumference of the shell 42 and are connected to each other to enclose a receiving space 428 .

[0146] According to some embodiments of the present application, Fig.13 As shown, the inner surface of the first plate portion 425 is recessed toward the outside of the housing 42 relative to the inner surface of the second plate portion 426. The inner surface of the first plate portion 425 refers to the surface of the first plate portion 425 facing the accommodation space. The inner surface of the second plate portion 426 refers to the surface of the second plate portion 426 facing the accommodation space.

[0147] In these embodiments, when the shell 42 is used in a battery cell and accommodates an electrode assembly, the first plate portion 425 is arranged away from the opening, the first plate portion 425 is close to the position where the electrode assembly is arranged, and the first plate portion 425 is recessed toward the outside of the shell 42 to leave sufficient arrangement space for the electrode assembly, thereby improving the energy density of the battery cell 40.

[0148] According to some embodiments of the present application, Fig.13 As shown, the outer surface of the first plate portion 425 is coplanar with the outer surface of the second plate portion 426. The outer surface of the first plate portion 425 is the surface of the first plate portion 425 away from the accommodation space, and the outer surface of the second plate portion 426 is the surface of the second plate portion 426 away from the accommodation space.

[0149] In these embodiments, the flatness of the outer surface of the shell 42 can be improved. When the shell 42 is the same as the battery cell, the shell 42 can be adjacently arranged through the second side plate 42b, which can reduce the distance between two adjacent battery cells 40 and reduce the total space size occupied by multiple battery cells.

[0150] Optional, such as Figures 8 to 10 and Fig.13 As shown, when the housing 42 is used for a square-shaped battery cell, the outer surfaces of the first plate portion 425 and the second plate portion 426 are both planar and located in the same plane.

[0151] Optional, such as Figures 11 to 13 As shown, when the housing 42 is used for a cylindrical battery cell, the outer surfaces of the first plate portion 425 and the second plate portion 426 are both arc-shaped and have the same curvature.

[0152] According to some embodiments of the present application, the area of ​​the first side plate 42 a is smaller than the area of ​​the second side plate 42 b .

[0153] In these embodiments, the thickened portion 422 and the support portion 423 are disposed on the first side plate 42a with a smaller area, so that the first side plate 42a with a smaller area is convex, and the outer surface of the second side plate 42b with a larger area can be more flat. When the housing 42 is used for a square battery cell, two adjacent battery cells can be opposite to each other through the side plate with a larger area.

[0154] According to some embodiments of the present application, Fig.13 As shown, the first plate portion 425 and the second plate portion 426 are connected by a second transition portion 427 , and the wall thickness of the second transition portion 427 gradually increases in the direction from the first plate portion 425 to the second plate portion 426 .

[0155] In these embodiments, the second transition portion 427 is provided to improve stress concentration caused by a sudden change in thickness between the first plate portion 425 and the second plate portion 426. At the same time, it is also possible to improve the problem that the shell 42 is easily scratched or the shell 42 easily scratches the electrode assembly 43 located therein due to a sudden change in thickness between the first plate portion 425 and the second plate portion 426.

[0156] There are many ways to connect the second transition portion 427 to the first plate portion 425 and the second plate portion 426. The second transition portion 427 can be welded to the first plate portion 425, or the second transition portion 427 can be integrally formed with the first plate portion 425. The second transition portion 427 can be welded to the second plate portion 426, or the second transition portion 427 can be integrally formed with the second plate portion 426.

[0157] Optionally, the second transition portion 427 , the first plate portion 425 and the second plate portion 426 are integrally formed, which can improve the connection strength between the second transition portion 427 and the first plate portion 425 and the second plate portion 426 .

[0158] According to some embodiments of the present application, Fig.13 As shown, the extension dimension H1 of the second plate portion 426 in the direction from the first plate portion 425 to the second plate portion 426 is 2 to 10 mm. The direction from the first plate portion 425 to the second plate portion 426 is the height direction Z of the housing 42 .

[0159] In these embodiments, when the extension dimension H1 of the second plate portion 426 in the height direction Z is within the above range, it can improve the structural strength of the shell 42 due to insufficient extension dimension H1 of the second plate portion 426, and can also improve the energy density of the battery cell 40 due to excessive extension dimension H1 of the second plate portion 426.

[0160] According to some embodiments of the present application, Fig.13 As shown, the extension dimension H2 of the second transition portion 427 in the direction from the first plate portion 425 to the second plate portion 426 is 1.5 mm to 20 mm.

[0161] In these embodiments, when the extension dimension H2 of the second transition portion 427 in the height direction Z is within the above range, it can improve the thickness mutation between the first plate portion 425 and the second plate portion 426 caused by insufficient extension dimension H2 of the second transition portion 427, and can also improve the energy density of the battery cell affected by excessive extension dimension H2 of the second transition portion 427.

[0162] According to some embodiments of the present application, Fig.13 As shown, the wall thickness T2 of the second plate portion 426 is 0.4 mm to 1.0 mm, and / or the wall thickness T1 of the first plate portion 425 is 0.3 mm to 1.0 mm.

[0163] In these embodiments, when the wall thickness of the second plate portion 426 and / or the first plate portion 425 is within the above range, it can improve the insufficient structural strength of the shell 42 caused by insufficient thickness of the second plate portion 426 and / or the first plate portion 425, and can also improve the energy density of the battery cell 40 affected by the excessive thickness of the second plate portion 426 and / or the first plate portion 425.

[0164] According to some embodiments of the present application, the difference between the wall thickness of the second plate portion 426 and the first plate portion 425 is 0.1 mm to 0.5 mm, and / or the ratio of the wall thickness of the second plate portion 426 to the first plate portion 425 is 1 to 1.5.

[0165] In these embodiments, when the wall thicknesses of the second plate portion 426 and the first plate portion 425 satisfy the above-mentioned relationship, it is possible to improve the problem of stress concentration caused by the excessively large difference in thickness between the first plate portion 425 and the second plate portion 426, and also to improve the problem of insufficient strength of the shell 42 caused by the excessively small difference in thickness between the first plate portion 425 and the second plate portion 426.

[0166] Please continue reading Figure 6 and Figure 7 According to some embodiments of the present application, the present application further provides a battery cell 40, the battery cell 40 includes a cover 41 and a shell 42, and the shell 42 can be the shell 42 of any of the above embodiments. Figures 8 to 13 As shown, the support portion 423 of the housing 42 supports the cover 41. Since the battery cell 40 of the embodiment of the present application includes the housing 42 described above, the battery cell 40 of the embodiment of the present application has the beneficial effects of the housing 42 of the above embodiment, which will not be described in detail.

[0167] In some embodiments, the housing 42 includes a first side plate 42a and a second side plate 42b which are circumferentially arranged around the opening and connected to each other, the body portion 421, the thickened portion 422 and the support portion 423 are arranged on the first side plate 42a, and the second side plate 42b includes a first plate portion 425 and a second plate portion 426 located on the side of the first plate portion 425 facing the opening, and the thickness of the first plate portion 425 is less than the thickness of the second plate portion 426;

[0168] The battery cell 40 further includes an electrode assembly 43 located in the housing 42 . In a direction perpendicular to the second side plate 42 b , projections of the electrode assembly 43 and the second plate portion 426 do not overlap.

[0169] In a direction perpendicular to the second side plate 42 b , the projections of the electrode assembly 43 and the second plate portion 426 are not overlapped, so that the thickened second plate portion 426 and the electrode assembly 43 are offset, and the second plate portion 426 does not interfere with the electrode assembly 43 .

[0170] According to some embodiments of the present application, the present application also provides a battery, comprising the battery cell described in any of the above schemes.

[0171] According to some embodiments of the present application, the present application further provides an electrical device, comprising the battery described in any of the above schemes, and the battery is used to provide electrical energy to the electrical device.

[0172] The power-consuming device may be any of the aforementioned devices or systems using batteries.

[0173] See also Figures 8 to 13 , Figures 8 to 13A schematic diagram of the structure of a shell 42 provided in an embodiment of the present application, wherein the shell 42 includes a body portion 421 and a thickened portion 422, which are connected to the body portion 421, and the thickened portion 422 is arranged at the opening of the shell 42, and the wall thickness of at least part of the thickened portion 422 is greater than the wall thickness of the body portion 421; wherein the thickened portion 422 is provided with a support portion 423, and the support portion 423 is used to support the cover body 41 that closes the opening. The thickened portion 422 includes a first portion 422a and a second portion 422b, wherein the first portion 422a is located on a side of the second portion 422b away from the opening, and the wall thickness of the second portion 422b is less than the wall thickness of the first portion 422a to form the support portion 423. The support portion 423 is located on the inner side of the shell 42. The outer surface of the first portion 422a and the outer surface of the second portion 422b are arranged in the same plane. The outer surface of the body portion 421 is arranged to be recessed toward the inside of the shell 42 relative to the outer surface of the thickened portion 422. The thickened portion 422 and the main body 421 are connected by the first transition portion 424. The wall thickness of the first transition portion 424 gradually increases along the direction from the main body 421 to the thickened portion 422. The inner surface of the main body 421, the inner surface of the first transition portion 424 and the inner surface of the second portion 422b are coplanar. The ratio of the wall thickness of the first portion 422a to the wall thickness of the main body 421 is 1 to 1.5. The shell 42 includes a plurality of side plates connected to each other, the plurality of side plates include a first side plate 42a and a second side plate 42b connected to each other, the main body 421, the thickened portion 422 and the support portion 423 are arranged on the first side plate 42a, the second side plate 42b includes a first plate portion 425 and a second plate portion 426 located on the side of the first plate portion 425 facing the opening, and the thickness of the first plate portion 425 is less than the thickness of the second plate portion 426. The inner surface of the first plate portion 425 is formed to be concave toward the outside of the shell 42 relative to the inner surface of the second plate portion 426. The outer surface of the first plate portion 425 is coplanar with the outer surface of the second plate portion 426, and the area of ​​the first side plate 42a is smaller than the area of ​​the second side plate 42b. The first plate portion 425 and the second plate portion 426 are connected by a second transition portion 427, and the wall thickness of the second transition portion 427 gradually increases in the direction from the first plate portion 425 to the second plate portion 426.

[0174] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: Cover body; A shell, comprising a plurality of side panels, wherein the plurality of side panels include a first side panel and a second side panel which are arranged around an opening of the shell and connected to each other, wherein an area of ​​the first side panel is smaller than an area of ​​the second side panel; The first side plate includes a main body and a thickened portion interconnected with the main body, and the thickened portion is arranged at the opening of the shell, the wall thickness of at least part of the thickened portion is greater than the wall thickness of the main body, and the outer surface of the main body is recessed toward the inside of the shell relative to the outer surface of the thickened portion; The thickened portion is provided with a support portion, and the support portion is used to support the cover body that closes the opening, the thickened portion includes a first portion and a second portion, the first portion is located between the second portion and the main body portion, the wall thickness of the second portion is smaller than the wall thickness of the first portion to form the support portion, the support portion is located inside the shell, the outer surface of the first portion and the outer surface of the second portion are coplanar, and the inner surface of the main body portion and the inner surface of the second portion are coplanar; The second side plate includes a first plate portion and a second plate portion located on a side of the first plate portion facing the opening, the thickness of the first plate portion is smaller than the thickness of the second plate portion, the inner surface of the first plate portion is recessed toward the outside of the shell relative to the inner surface of the second plate portion, and the outer surface of the first plate portion and the outer surface of the second plate portion are coplanar; The electrode assembly is disposed in the shell, and in a direction perpendicular to the second side plate, projections of the electrode assembly and the second plate portion do not overlap.

2. The battery cell according to claim 1, characterized in that: The support portion includes a support surface for supporting the cover body, and an extension dimension of the support surface along a thickness direction of the main body portion is 0.05 mm to 2 mm.

3. The battery cell according to claim 1, characterized in that: The thickened portion and the main body portion are connected via a first transition portion, and the wall thickness of the first transition portion gradually increases along a direction from the main body portion to the thickened portion.

4. The battery cell according to claim 3, characterized in that: An inner surface of the body portion, an inner surface of the first transition portion, and an inner surface of the second portion are coplanar.

5. The battery cell according to claim 3, characterized in that: An extension dimension of the first transition portion in a direction from the main body portion to the thickened portion is 2 mm to 20 mm.

6. The battery cell according to claim 1, characterized in that: The wall thickness of the first part is 0.6 mm to 1.2 mm, and / or the wall thickness of the second part is 0.4 mm to 1 mm, and / or the wall thickness of the main body is 0.5 mm to 1.0 mm.

7. The battery cell according to claim 1, characterized in that: The ratio of the wall thickness of the first portion to the wall thickness of the main body is 1 to 1.

5.

8. The battery cell according to claim 1, characterized in that: An extension dimension of the thickened portion in a direction from the main body to the thickened portion is 2 mm to 12 mm.

9. The battery cell according to claim 1, characterized in that: The first plate portion and the second plate portion are connected via a second transition portion, and a wall thickness of the second transition portion gradually increases in a direction from the first plate portion to the second plate portion.

10. The battery cell according to claim 9, characterized in that: An extension dimension of the second plate portion in a direction from the first plate portion to the second plate portion is 2 to 10 mm; and / or an extension dimension of the second transition portion in a direction from the first plate portion to the second plate portion is 1.5 to 20 mm.

11. The battery cell according to claim 1, characterized in that: The wall thickness of the second plate portion is 0.4 mm to 1.0 mm; and / or the wall thickness of the first plate portion is 0.3 mm to 1.0 mm.

12. The battery cell according to claim 1, characterized in that: The difference between the thickness of the second plate portion and the first plate portion is 0.1 mm to 0.5 mm; and / or the ratio of the thickness of the second plate portion to the thickness of the first plate portion is 1 to 1.

5.

13. A battery, characterized in that: The invention comprises a box body and a plurality of battery cells according to any one of claims 1 to 12, wherein the battery cells are accommodated in the box body.

14. An electrical device, characterized in that: The electrical device comprises a battery cell as claimed in any one of claims 1 to 12, and the battery cell is used to provide electrical energy.

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