Casing, battery cell, battery and electrical device

Abstract

The present application provides a shell, a battery cell, a battery and an electrical device, belonging to the field of battery technology. The shell includes a first wall, a second wall and a first insulating member. The second wall is arranged around the first wall, one end of the second wall in a preset direction is connected to the first wall, and the other end of the second wall in the preset direction forms an opening, and the second wall and the first wall together define a storage space for accommodating an electrode assembly. The first insulating member is arranged in the storage space, the first insulating member is thermally composited to the first wall, and the first insulating member is used to separate the first wall and the electrode assembly. A shell with such a structure can enhance the bonding strength between the first insulating member and the first wall, thereby helping to reduce the risk of the first insulating member and the first wall falling off or generating a gap, so as to provide better protection for the shell, which is beneficial to improving the anti-corrosion and anti-leakage capabilities of the shell, and thus can improve the service life of the battery cell.

Description

Technical Field

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

[0002] Lithium-ion batteries have outstanding advantages such as high energy density, low environmental pollution, high power density, long service life, wide adaptability, and low self-discharge coefficient. They are one of the most widely used batteries in the world today and an important part of the development of new energy. With the continuous development of lithium-ion battery technology, higher requirements are also placed on the performance and service life of lithium-ion batteries. The battery cell of a lithium-ion battery is assembled into an electrode assembly by winding or laminating the positive electrode sheet, the negative electrode sheet, and the isolation film, which is then loaded into a shell, injected with electrolyte, and finally covered with an end cap. In the production process of the battery cell, it is necessary to wrap an insulating film on the outside of the electrode assembly and set a bottom support plate at the bottom of the shell to achieve electrical isolation between the electrode assembly and the shell. However, the battery cell using this structure has poor performance and a short service life. Summary of the invention

[0003] The embodiments of the present application provide a housing, a battery cell, a battery and an electrical device, which can effectively improve the performance and service life of the battery cell.

[0004] In a first aspect, an embodiment of the present application provides a shell for accommodating an electrode assembly, the shell comprising a first wall, a second wall and a first insulating member; the second wall is arranged around the first wall, one end of the second wall in a preset direction is connected to the first wall, and the other end of the second wall in the preset direction forms an opening, and the second wall and the first wall jointly define a accommodating space for accommodating the electrode assembly; the first insulating member is arranged in the accommodating space, the first insulating member is thermally composited with the first wall, and the first insulating member is used to separate the first wall and the electrode assembly.

[0005] In the above technical solution, a first insulating member for separating the electrode assembly and the first wall is provided in the accommodating space of the shell. By thermally compounding the first insulating member on the first wall, the bonding strength between the first insulating member and the first wall can be effectively improved, so that when vibration occurs during the use of the battery cell or gas is generated inside the battery cell to cause the shell to expand, the risk of the first insulating member falling off or a gap being generated between the first insulating member and the first wall can be reduced. On the one hand, a shell with such a structure can realize the insulation isolation between the electrode assembly and the first wall of the shell, so as to replace the bottom support plate provided in the shell for isolating the shell and the electrode assembly, thereby alleviating the phenomenon that the electrolyte in the shell is blocked by the bottom support plate when it refluxes and causes poor wetting of the electrode assembly, which is beneficial to improving the performance of the battery cell with such a shell. On the other hand, it can play a certain protective role on the shell, effectively reducing the particles and powder dropped from the electrode assembly and the direct contact between the electrolyte and the first wall of the shell, which is beneficial to improving the corrosion resistance and leakage resistance of the shell, and thus can improve the service life of the battery cell. In addition, during the production process of the battery cell, the process of installing the bottom support plate at the bottom of the electrode assembly is eliminated, and the first insulating member can be thermally composited to the first wall of the shell in the production branch line of the shell to complete the covering process of the first insulating member, so that the shell can be produced in parallel with the battery cell. That is to say, when the shell enters the production assembly line of the battery cell, the covering process of the first insulating member has been completed, so that the covering process of the first insulating member will not occupy the production rhythm of the battery cell, which is beneficial to improve the production efficiency of the battery cell.

[0006] In some embodiments, a chamfer is formed at a connection between the first wall and the second wall; in a preset direction, a thickness of the first insulating member is greater than a height of the chamfer.

[0007] In the above technical solution, by setting the thickness of the first insulating part to be greater than the height of the chamfer in a preset direction, the phenomenon of collision between the electrode assembly and the chamfer of the shell can be effectively reduced when the electrode assembly is assembled into the accommodating space of the shell, and the phenomenon of the electrode assembly being squeezed or impacted by the chamfer of the shell can be reduced during use, which is beneficial to reduce the risk of deformation or damage of the electrode assembly during use or assembly.

[0008] In some embodiments, the first insulating member has a thickness of 0.1-0.8 mm.

[0009] In the above technical solution, by setting the thickness of the first insulating member between 0.1 mm and 0.8 mm, on the one hand, the phenomenon of poor insulation effect and short service life of the first insulating member caused by the first insulating member being too thin can be reduced, so as to ensure the insulation effect and use reliability of the first insulating member; on the other hand, the influence of the excessive thickness of the first insulating member on the capacity of the accommodating space of the shell can be alleviated, so as to ensure the energy density of the battery cell with such a shell.

[0010] In some embodiments, the first insulating member has a plurality of first pores that allow at least part of the gas to pass through and prevent the electrolyte from passing through; and the first wall is provided with a first vent hole for allowing at least part of the gas to pass through.

[0011] In the above technical solution, the first insulating member has a plurality of first pores, which can allow some gas to pass through and prevent electrolyte from passing through. By opening a first vent hole on the first wall, the gas in the accommodating space of the shell can pass through the first insulating member and then be discharged to the outside of the shell through the first vent hole, thereby alleviating the phenomenon of flatulence or swelling of the battery cell with such a shell, which is beneficial to improving the safety and service life of the battery cell.

[0012] In some embodiments, the pore size of the first pore is 0.4-189 nm.

[0013] In the above technical solution, by setting the pore size of the first pore to between 0.4nm and 189nm, the pore size of the first pore is larger than the diameter of some gas molecules and smaller than the diameter of liquid molecules of the electrolyte, thereby achieving the first insulating member allowing some gas to pass through but preventing the electrolyte from passing through.

[0014] In some embodiments, a first nano-plating layer is formed on the first wall, and the first insulating member is thermally composited with the first nano-plating layer.

[0015] In the above technical solution, by forming the first nano-coating layer on the first wall and thermally compounding the first insulating member on the first nano-coating layer of the first wall, the bonding strength between the first insulating member and the first wall can be further improved to reduce the risk of the first insulating member falling off, thereby helping to improve the reliability of the shell during use.

[0016] In some embodiments, the material of the first insulating element has a polar group.

[0017] In the above technical solution, a first insulating member is made of a material having a polar group, that is, the first insulating member has a polar group. The polar group can effectively improve the bonding strength between the first insulating member and the first wall of the shell, thereby further improving the bonding strength between the first insulating member and the first wall.

[0018] In some embodiments, the shell further includes a second insulating member; the second insulating member is disposed in the accommodation space along the circumference of the second wall, the second insulating member is thermally composited to the second wall, and the second insulating member is used to separate the second wall and the electrode assembly.

[0019] In the above technical solution, a second insulating member for separating the electrode assembly and the second wall is also provided in the accommodating space of the shell. By thermally compounding the second insulating member on the second wall, the bonding strength between the second insulating member and the second wall can be improved, so that when vibration occurs during the use of the battery cell or gas is generated inside the battery cell to cause the shell to expand, the risk of the second insulating member falling off or a gap between the second insulating member and the second wall can be reduced. Therefore, a shell with such a structure can, on the one hand, realize the insulation isolation between the electrode assembly and the second wall of the shell, instead of providing an insulating film in the shell for isolating the shell and the electrode assembly, thereby reducing the electrolyte from being free between the second wall and the insulating film, so as to alleviate the phenomenon that the electrolyte in the shell is blocked by the insulating film when it refluxes and causes poor wetting of the electrode assembly, which is beneficial to improving the performance of the battery cell with such a shell. On the other hand, it can play a certain protective role on the shell, effectively reducing the direct contact between the electrolyte and the second wall of the shell, which is beneficial to improving the corrosion resistance and leakage resistance of the shell, thereby improving the service life of the battery cell. In addition, in the production process of the battery cell, the process of setting an insulating film on the outer peripheral side of the electrode assembly is eliminated, and the second insulating member can be thermally composited to the second wall of the shell in the production branch line of the shell to complete the covering process of the second insulating member, so that the shell can be produced in parallel with the battery cell. That is to say, when the shell enters the production assembly line of the battery cell, the covering process of the second insulating member has been completed, so that the covering process of the second insulating member will not occupy the production rhythm of the battery cell, which is beneficial to improve the production efficiency of the battery cell.

[0020] In some embodiments, in a preset direction, a distance between an edge of the second insulating member close to the opening and the opening is 1-8 mm.

[0021] In the above technical solution, the edge of the second insulating member close to the opening of the shell is spaced apart from the opening, that is, the edge of the second insulating member close to the opening of the shell is spaced apart from the opening at a certain distance, so as to reduce the influence and interference of the second insulating member on the end cover of the battery cell when it is covered on the opening of the shell, thereby ensuring the reliability of the connection between the end cover and the shell.

[0022] In some embodiments, the second insulating member has a thickness of 0.03-0.5 mm.

[0023] In the above technical solution, by setting the thickness of the second insulating member between 0.03 mm and 0.5 mm, on the one hand, the phenomenon of poor insulation effect and short service life of the second insulating member caused by the second insulating member being too thin can be reduced, so as to ensure the insulation effect and use reliability of the second insulating member; on the other hand, the influence of the excessive thickness of the second insulating member on the capacity of the accommodating space of the shell can be alleviated, so as to ensure the energy density of the battery cell with such a shell.

[0024] In some embodiments, the second insulating member has a plurality of second pores that allow at least part of the gas to pass through and prevent the electrolyte from passing through; and the second wall is provided with second vent holes for allowing at least part of the gas to pass through.

[0025] In the above technical solution, the second insulating member has a plurality of second pores, which can allow some gas to pass through and prevent electrolyte from passing through. By opening a second vent hole on the second wall, the gas in the accommodating space of the shell can pass through the second insulating member and then be discharged to the outside of the shell through the second vent hole, thereby alleviating the phenomenon of flatulence or swelling of the battery cell with such a shell, which is beneficial to improving the safety and service life of the battery cell.

[0026] In some embodiments, the pore size of the second pore is 0.4-189 nm.

[0027] In the above technical solution, by setting the pore size of the second pore to between 0.4nm and 189nm, the pore size of the second pore is larger than the diameter of some gas molecules and smaller than the diameter of liquid molecules of the electrolyte, thereby achieving the second insulating member that allows some gas to pass through but prevents the electrolyte from passing through.

[0028] In some embodiments, the second insulating member overlaps with the first and last ends of the second wall in the circumferential direction and is thermally composited to form an overlapping area.

[0029] In the above technical solution, the second insulating member is laid on the second wall along the circumference of the second wall, and the head and tail ends of the second insulating member in the circumference of the second wall are overlapped with each other and then thermally composited and connected. A shell with such a structure can, on the one hand, improve the connection strength of the head and tail ends of the second insulating member, and on the other hand, alleviate the risk of gaps in the second insulating member, so as to reduce the phenomenon that the electrolyte in the shell enters between the second insulating member and the second wall through the gaps in the second insulating member, thereby helping to improve the protective effect of the second insulating member on the shell.

[0030] In some embodiments, the second wall includes a plurality of walls connected end to end in sequence along its circumference, and a corner area is formed at the connection between every two adjacent walls; and the overlapping area is arranged corresponding to the corner area.

[0031] In the above technical solution, since the electrode assembly in the shell cannot be completely fitted in the corner area of ​​the second wall, there is a gap between the electrode assembly and the corner area of ​​the second wall, and the overlapping area is the area protruding from the second wall after the head and tail ends of the second insulating member overlap with each other. Therefore, by setting the overlapping area of ​​the second insulating member corresponding to the corner area of ​​the second wall, on the one hand, the collision between the electrode assembly and the overlapping area can be reduced, and on the other hand, the influence of the overlapping area on the capacity of the electrode assembly in the accommodating space can be effectively reduced.

[0032] In some embodiments, the second wall is formed with a second nano-plating layer, and the second insulating member is thermally composited with the second nano-plating layer.

[0033] In the above technical solution, by forming a second nano-coating layer on the second wall and thermally compounding the second insulating member on the second nano-coating layer of the second wall, the bonding strength between the second insulating member and the second wall can be further improved to reduce the risk of the second insulating member falling off, thereby helping to improve the reliability of the shell during use.

[0034] In some embodiments, the second nano-plating layer is an annular structure extending along the circumference of the second wall; in a preset direction, the second nano-plating layer extends from an edge of the second insulating member close to the opening toward a direction facing the first wall.

[0035] In the above technical solution, by setting the second nano-coating as an annular structure extending along the circumference of the second wall, and extending along a preset direction from the edge of the second insulating member toward the direction facing the first wall, it is ensured that the second nano-coating is formed in the area where the edge of the second insulating member and the second wall are thermally composited, thereby improving the bonding strength between the edge of the second insulating member and the second wall, and further effectively alleviating the phenomenon of electrolyte penetrating from the edge of the second insulating member into between the second insulating member and the second wall.

[0036] In some embodiments, the material of the second insulating element has a polar group.

[0037] In the above technical solution, a second insulating member is made of a material having a polar group, that is, the second insulating member has a polar group. The polar group can effectively improve the bonding strength between the second insulating member and the second wall of the shell, thereby further improving the bonding strength between the second insulating member and the second wall.

[0038] In some embodiments, the first insulating member is thermally compositely connected to the second insulating member at one end away from the opening in a preset direction.

[0039] In the above technical solution, by thermally compositely connecting the first insulating member and one end of the second insulating member, on the one hand, the connection strength between the first insulating member and the second insulating member can be improved, and on the other hand, the phenomenon of a gap between the first insulating member and the second insulating member can be reduced, thereby reducing the risk of electrolyte infiltration from the gap between the first insulating member and the second insulating member.

[0040] In a second aspect, an embodiment of the present application further provides a battery cell, comprising an electrode assembly, an end cover and the above-mentioned shell; the electrode assembly is placed in the shell, and the end cover covers the opening of the shell.

[0041] In a third aspect, an embodiment of the present application further provides a battery, comprising a housing and the above-mentioned battery cell; the housing is used to accommodate the battery cell.

[0042] In a fourth aspect, an embodiment of the present application further provides an electrical device, comprising the above-mentioned battery; the battery is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0044] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0045] Figure 2 An exploded view of the structure of a battery provided in some embodiments of the present application;

[0046] Figure 3 An exploded view of the structure of a battery cell provided in some embodiments of the present application;

[0047] Figure 4 A cross-sectional view of a housing provided for some embodiments of the present application;

[0048] Figure 5 for Figure 4 A partial enlarged view of the shell at A shown;

[0049] Figure 6 for Figure 4 A partial enlarged view of the B portion of the shell shown;

[0050] Figure 7 for Figure 4 A partial enlarged view of the C portion of the shell shown;

[0051] Figure 8 for Figure 4A partial enlarged view of a portion D of the shell shown;

[0052] Fig. 9 A cross-sectional view of a battery cell provided for some embodiments of the present application;

[0053] Fig.10 for Fig. 9 A partial enlarged view of the battery cell at position E shown;

[0054] Fig.11 A cross-sectional view of a battery cell provided for some other embodiments of the present application;

[0055] Fig.12 for Fig.11 A partial enlarged view of the F portion of the battery cell shown;

[0056] Fig.13 A schematic diagram of the structure of the second wall provided in some embodiments of the present application.

[0057] Icons: 1000-vehicle; 100-battery; 10-casing; 11-first part; 12-second part; 20-battery cell; 21-electrode assembly; 22-end cap; 23-shell; 231-opening; 232-first wall; 2321-first vent; 233-second wall; 2331-second vent; 2332-corner area; 2333-second nano-coating; 234-first insulating member; 235-accommodating space; 236-chamfer; 237-second insulating member; 2371-overlapping area; 24-positive electrode terminal; 25-negative electrode terminal; 26-pressure relief mechanism; 200-controller; 300-motor; X-preset direction. DETAILED DESCRIPTION

[0058] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0059] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0060] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0061] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" 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 direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0062] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0063] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0064] The term "plurality" used in the present application refers to two or more (including two).

[0065] In the present application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries or magnesium-ion batteries, etc., and the embodiments of the present application do not limit this. Battery cells may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this. Battery cells are 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.

[0066] 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.

[0067] The battery cell includes an electrode assembly and an electrolyte. The electrode assembly is composed of a positive electrode sheet, a negative electrode sheet and a separator. The battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode collector. The positive electrode collector not coated with the positive electrode active material layer protrudes from the positive electrode collector coated with the positive electrode active material layer. The positive electrode collector not coated with the positive electrode active material layer serves as the positive electrode tab. Taking lithium-ion batteries as an example, the material of the positive electrode collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide. The negative electrode sheet includes a negative electrode collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode collector. The negative electrode collector not coated with the negative electrode active material layer protrudes from the negative electrode collector coated with the negative electrode active material layer. The negative electrode collector not coated with the negative electrode active material layer serves as the negative electrode tab. The negative electrode current collector may be made of copper, and the negative electrode active material may be carbon or silicon, etc. In order to ensure that a large current is passed without melting, the number of positive electrode tabs is multiple and stacked together, and the number of negative electrode tabs is multiple and stacked together.

[0068] The material of the isolation film may be PP (polypropylene) or PE (polyethylene), etc. In addition, the electrode assembly may be a winding structure or a stacked structure, but the embodiments of the present application are not limited thereto.

[0069] Lithium-ion batteries have outstanding advantages such as high energy density, low environmental pollution, high power density, long service life, wide adaptability, and low self-discharge coefficient. They are one of the most widely used batteries in the world today and an important part of the development of new energy. With the continuous development of battery technology, higher requirements are also put forward for battery performance and service life.

[0070] The inventors found that in order to improve the safety of battery use and reduce the phenomenon of contact short circuit between the electrode assembly and the shell of the battery cell, in the prior art, an insulating film is usually wrapped on the outside of the electrode assembly and a bottom support plate is set at the bottom of the shell to achieve electrical isolation between the electrode assembly and the shell. However, the electrolyte in the shell of the battery cell of this structure will be blocked by the insulating film and the bottom support plate, which will easily cause poor electrolyte reflux effect, which is not conducive to the infiltration of the electrode assembly, and further affects the performance of the battery cell. In addition, the insulating film and the bottom support plate cannot protect the shell of the battery cell. The particles and powders shed from the electrode assembly and the electrolyte will directly contact the shell, which is prone to galvanic corrosion, thereby causing the risk of leakage, which is not conducive to extending the service life of the battery cell.

[0071] Based on the above considerations, in order to solve the problems of poor performance and short service life of battery cells, the inventors have designed a shell after in-depth research. The shell is used to accommodate the electrode assembly. The shell includes a first wall, a second wall and a first insulating member. The second wall is arranged around the first wall, and one end of the second wall in a preset direction is connected to the first wall, and the other end forms an opening. The first insulating member is arranged in the shell and thermally composited on the first wall, so that the first insulating member can separate the first wall and the electrode assembly, so that the first wall and the electrode assembly are insulated and isolated.

[0072] In the above-mentioned shell, a first insulating member is arranged between the electrode assembly and the first wall of the shell. By thermally compounding the first insulating member on the first wall, the bonding strength between the first insulating member and the first wall can be effectively improved, so that when vibration occurs during the use of the battery cell or gas is generated inside the battery cell to cause the shell to expand, the risk of the first insulating member falling off or a gap being generated between the first insulating member and the first wall can be reduced. Therefore, a shell with such a structure can, on the one hand, realize the insulation isolation between the electrode assembly and the shell, instead of providing a bottom support plate in the shell for isolating the shell and the electrode assembly, thereby alleviating the phenomenon that the electrolyte in the shell is blocked by the bottom support plate when it refluxes and causes poor wetting of the electrode assembly, which is beneficial to improving the performance of the battery cell with such a shell. On the other hand, it can play a certain protective role on the shell, effectively reducing the particles and powder dropped from the electrode assembly and the direct contact between the electrolyte and the first wall of the shell, which is beneficial to improving the corrosion resistance and leakage resistance of the shell, and thus can improve the service life of the battery cell.

[0073] In addition, during the production of battery cells, the process of installing the bottom support plate at the bottom of the electrode assembly is eliminated, and the first insulating member can be thermally composited to the first wall of the shell in the production branch line of the shell to complete the covering process of the first insulating member, so that the shell can be produced in parallel with the battery cell. That is to say, when the shell enters the production assembly line of the battery cell, the covering process of the first insulating member has been completed, so that the covering process of the first insulating member will not occupy the production rhythm of the battery cell, which is beneficial to improve the production efficiency of the battery cell.

[0074] The housing disclosed in the embodiment of the present application can be used, but not limited to, in electrical devices such as vehicles, ships or aircraft. A power supply system of the electrical device can be composed of the housing disclosed in the present application, battery cells, etc., which is helpful to alleviate the phenomenon of poor electrolyte infiltration and leakage in the battery cells, thereby improving the performance and service life of the battery cells.

[0075] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, 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, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0076] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0077] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 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 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0078] In some embodiments of the present application, the battery 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0079] Please refer to Figure 2 , Figure 2 The structural exploded diagram of the battery 100 provided for some embodiments of the present application. The battery 100 includes a box 10 and a battery cell 20, and the box 10 is used to accommodate the battery cell 20. Among them, the box 10 is used to provide an assembly space for the battery cell 20, and the box 10 can adopt a variety of structures. In some embodiments, the box 10 may include a first part 11 and a second part 12, and the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define an assembly space for accommodating the battery cell 20. The second part 12 can be a hollow structure with one end open, and the first part 11 can be a plate-like structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define an assembly space; the first part 11 and the second part 12 can also be hollow structures with one side open, and the open side of the first part 11 covers the open side of the second part 12. Of course, the box 10 formed by the first part 11 and the second part 12 can be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0080] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10; of course, the battery 100 may also be a battery module formed by connecting multiple battery cells 20 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 10. The battery 100 may also include other structures, for example, the battery 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0081] Each battery cell 20 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0082] Please refer to Figure 3 , Figure 3 The structure of the battery cell 20 provided in some embodiments of the present application is an exploded view. The battery cell 20 includes an electrode assembly 21, an end cap 22 and a shell 23, the shell 23 is used to accommodate the electrode assembly 21, one end of the shell 23 forms an opening 231, and the end cap 22 is used to cover the opening 231 of the shell 23 to form the battery cell 20.

[0083] The housing 23 can also be used to contain electrolytes, such as electrolytes. The housing 23 can be in various structural forms. The housing 23 can also be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc.

[0084] In some embodiments, one end of the shell 23 has an opening 231, that is, the shell 23 is a hollow structure with an opening 231 at one end, and the end cover 22 covers the opening 231 of the shell 23 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 21 and the electrolyte.

[0085] When assembling the battery cell 20 , the electrode assembly 21 may be placed in the housing 23 first, and the housing 23 may be filled with electrolyte, and then the end cap 22 may be closed on the opening 231 of the housing 23 .

[0086] The shell 23 can be in various shapes, such as a cylinder, a cuboid, etc. The shape of the shell 23 can be determined according to the specific shape of the electrode assembly 21. For example, if the electrode assembly 21 is a cylindrical structure, a cylindrical shell can be selected; if the electrode assembly 21 is a cuboid structure, a cuboid shell can be selected. Of course, the end cap 22 can also be in various structures, such as a plate-like structure or a hollow structure with one end open. For example, in Figure 3 In the embodiment, the shell 23 is a rectangular parallelepiped structure, the end cover 22 is a plate-shaped structure, and the end cover 22 covers the opening 231 of the shell 23 .

[0087] In some embodiments, the battery cell 20 may further include a positive electrode terminal 24, a negative electrode terminal 25, and a pressure relief mechanism 26, which are all mounted on the end cap 22. The positive electrode terminal 24 and the negative electrode terminal 25 are both used to be electrically connected to the electrode assembly 21. The pressure relief mechanism 26 is used to release the pressure inside the battery cell 20 when the internal pressure or temperature of the battery cell 20 reaches a predetermined value.

[0088] For example, Figure 3 As shown, the pressure relief mechanism 26 is located between the positive electrode terminal 24 and the negative electrode terminal 25. The pressure relief mechanism 26 can be a component such as an explosion-proof valve, an explosion-proof disk, a gas valve, a pressure relief valve or a safety valve.

[0089] It is understandable that the battery cell 20 is not limited to the above structure, and the battery cell 20 may also be other structures. For example, the battery cell 20 includes a shell 23 and two end caps 22. The shell 23 is a hollow structure with two opposite openings 231 at both ends. One end cap 22 is correspondingly covered at one opening 231 of the shell 23 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 21 and the electrolyte. In this structure, the positive electrode terminal 24 and the negative electrode terminal 25 can be installed on the same end cap 22 or on different end caps 22; the pressure relief mechanism 26 can be installed on one end cap 22 or on both end caps 22.

[0090] It should be noted that, in the embodiment of the present application, the electrode assembly 21 contained in the housing 23 may be one or more. Figure 3 In the embodiment, there are two electrode assemblies 21, and the two electrode assemblies 21 are stacked.

[0091] The electrode assembly 21 is a component where an electrochemical reaction occurs in the battery cell 20. The electrode assembly 21 may include a positive electrode sheet, a negative electrode sheet, and a separator. The electrode assembly 21 may be a wound structure formed by winding the positive electrode sheet, the separator, and the negative electrode sheet, or a stacked structure formed by stacking the positive electrode sheet, the separator, and the negative electrode sheet.

[0092] According to some embodiments of the present application, referring to Figure 3 , and please refer to Figure 4 and Figure 5 , Figure 4 A cross-sectional view of a housing 23 provided in some embodiments of the present application, Figure 5 for Figure 4 A partial enlarged view of the A portion of the shell 23 shown. The present application provides a shell 23, which includes a first wall 232, a second wall 233 and a first insulating member 234. The second wall 233 is arranged around the first wall 232, one end of the second wall 233 in the preset direction X is connected to the first wall 232, and the other end of the second wall 233 in the preset direction X forms an opening 231, and the second wall 233 and the first wall 232 jointly define a receiving space 235 for receiving the electrode assembly 21. The first insulating member 234 is arranged in the receiving space 235, and the first insulating member 234 is thermally compounded with the first wall 232, and the first insulating member 234 is used to separate the first wall 232 and the electrode assembly 21.

[0093] The first insulating member 234 is thermally bonded to the first wall 232 of the shell 23, that is, the first insulating member 234 is combined with the first wall 232 of the shell 23 after hot melting, so that the first insulating member 234 is hot-melted and bonded to the first wall 232, thereby eliminating the need to provide an adhesive between the first insulating member 234 and the first wall 232. The first insulating member 234 is used to separate the first wall 232 and the electrode assembly 21, so as to achieve insulation isolation between the electrode assembly 21 and the first wall 232 of the shell 23, that is, the first insulating member 234 achieves electrical isolation between the electrode assembly 21 and the first wall 232 of the shell 23.

[0094] Optionally, the first insulating member 234 is a film structure of an organic polymer insulating material, and the first insulating member 234 is laid on the first wall 232 of the shell 23. The first insulating member 234 has good acid resistance and alkali resistance, and can withstand strong acids with a pH value less than 7 and strong alkalis with a pH value greater than 12. Exemplarily, the material of the first insulating member 234 can be polypropylene or polyethylene terephthalate.

[0095] By thermally bonding the first insulating member 234 to the first wall 232, the bonding strength between the first insulating member 234 and the first wall 232 can be effectively improved, so that when vibration occurs during the use of the battery cell 20 or gas is generated inside the battery cell 20 to cause the shell 23 to expand, the risk of the first insulating member 234 and the first wall 232 falling off or generating a gap can be reduced. The shell 23 with such a structure can achieve insulation isolation between the electrode assembly 21 and the first wall 232 of the shell 23, instead of setting a The bottom support plate is used to isolate the shell 23 and the electrode assembly 21, so as to alleviate the phenomenon that the electrolyte in the shell 23 is blocked by the bottom support plate when it refluxes, resulting in poor infiltration of the electrode assembly 21, which is beneficial to improving the performance of the battery cell 20 with such a shell 23. On the other hand, it can play a certain protective role on the shell 23, effectively reducing the particles and powder dropped from the electrode assembly 21 and the direct contact between the electrolyte and the first wall 232 of the shell 23, which is beneficial to improving the corrosion resistance and leakage resistance of the shell 23, and thus can increase the service life of the battery cell 20. In addition, during the production process of the battery cell 20, the process of installing the bottom support plate at the bottom of the electrode assembly 21 is eliminated, and the first insulating member 234 can be thermally composited to the first wall 232 of the shell 23 in the production branch line of the shell 23 to complete the covering process of the first insulating member 234, so that the shell 23 can be produced in parallel with the battery cell 20. That is to say, when the shell 23 enters the production assembly line of the battery cell 20, the covering process of the first insulating member 234 has been completed, so that the covering process of the first insulating member 234 will not occupy the production rhythm of the battery cell 20, which is beneficial to improve the production efficiency of the battery cell 20.

[0096] According to some embodiments of this application, please refer to Figure 4 and Figure 5 A chamfer 236 is formed at the connection between the first wall 232 and the second wall 233. In the preset direction X, the thickness of the first insulating member 234 is greater than the height of the chamfer 236.

[0097] The connection between the first wall 232 and the second wall 233 forms a chamfer 236, that is, the end of the second wall 233 away from the opening 231 in the preset direction X forms a chamfer 236 when connected to the outer peripheral surface of the first wall 232, so as to facilitate processing. In the preset direction X, the thickness of the first insulating member 234 is greater than the height of the chamfer 236, that is, in the preset direction X, the first insulating member 234 covers the chamfer 236 of the first wall 232 and the second wall 233.

[0098] By setting the thickness of the first insulating member 234 to be greater than the height of the chamfer 236 in the preset direction X, the phenomenon of collision between the electrode assembly 21 and the chamfer 236 of the shell 23 can be effectively reduced when the electrode assembly 21 is assembled into the accommodating space 235 of the shell 23, and the phenomenon of the electrode assembly 21 being squeezed or impacted by the chamfer 236 of the shell 23 can be reduced during use, thereby helping to reduce the risk of deformation or damage of the electrode assembly 21 during use or assembly.

[0099] According to some embodiments of the present application, the thickness of the first insulating member 234 is 0.1-0.8 mm.

[0100] By setting the thickness of the first insulating member 234 between 0.1 mm and 0.8 mm, on the one hand, the phenomenon of poor insulation effect and short service life of the first insulating member 234 caused by too small thickness of the first insulating member 234 can be reduced, so as to ensure the insulation effect and reliability of use of the first insulating member 234. On the other hand, the influence of excessive thickness of the first insulating member 234 on the capacity of the accommodating space 235 of the shell 23 can be alleviated, so as to ensure the energy density of the battery cell 20 having such a shell 23.

[0101] According to some embodiments of the present application, referring to Figure 4 , and please refer to Figure 6 , Figure 6 for Figure 4 The first insulating member 234 has a plurality of first pores that allow at least part of the gas to pass through and prevent the electrolyte from passing through. The first wall 232 is provided with a first vent hole 2321 for at least part of the gas to pass through.

[0102] Among them, the first insulating member 234 has multiple first pores that allow at least part of the gas to pass through and prevent the electrolyte from passing through, that is, the material of the first insulating member 234 is formed with multiple first pores, and the first pores can allow part of the gas in the shell 23 to pass through, but can prevent the electrolyte in the shell 23 from passing through, so that the first insulating member 234 has selective permeability.

[0103] Optionally, the number of the first vent hole 2321 formed on the first wall 232 may be one or more. Figure 6 In the embodiment, there is one first vent hole 2321 formed on the first wall 232. In other embodiments, there may be two, three, four, etc. first vent holes 2321.

[0104] The first insulating member 234 has a plurality of first pores, which can allow some gas to pass through and prevent electrolyte from passing through. By opening a first vent hole 2321 on the first wall 232, the gas in the accommodating space 235 of the shell 23 can pass through the first insulating member 234 and then be discharged to the outside of the shell 23 through the first vent hole 2321, thereby alleviating the flatulence or bulging phenomenon of the battery cell 20 having such a shell 23, which is beneficial to improving the safety and service life of the battery cell 20.

[0105] Furthermore, the pore size of the first pore is 0.4-189 nm.

[0106] During the use of the battery cell 20, the main gases generated in the housing 23 are hydrogen, carbon monoxide, carbon dioxide and methane, etc. The kinetic diameter of hydrogen is 0.289nm, the kinetic diameter of carbon monoxide is 0.376nm, the kinetic diameter of carbon dioxide is 0.33nm, and the kinetic diameter of methane is 0.38nm. The kinetic diameters of these gases are all less than 0.4nm, so that the first insulating member 234 can allow these gases to pass through. Among them, the molecular diameter of the electrolyte in the housing 23 is less than 189nm, so that liquid water and solvents cannot pass through the first insulating member 234.

[0107] By setting the pore size of the first pore to between 0.4 nm and 189 nm, the pore size of the first pore is larger than the diameter of some gas molecules and smaller than the diameter of liquid molecules of the electrolyte, thereby achieving the first insulating member 234 being able to allow some gas to pass through but preventing the electrolyte from passing through.

[0108] According to some embodiments of the present application, a first nano-plating layer is formed on the first wall 232 , and the first insulating member 234 is thermally composited with the first nano-plating layer.

[0109] A first nano-plating layer is formed on the first wall 232, that is, a side of the first wall 232 facing the first insulating member 234 in the preset direction X is nano-processed to form the first nano-plating layer on the first wall 232. It should be noted that if a first vent hole 2321 is required to be opened on the first wall 232, the first vent hole 2321 needs to be processed on the first wall 232 first, and then the first wall 232 needs to be nano-processed.

[0110] By forming a first nano-coating layer on the first wall 232 and thermally compounding the first insulating member 234 on the first nano-coating layer of the first wall 232, the bonding strength between the first insulating member 234 and the first wall 232 can be further improved, thereby reducing the risk of the first insulating member 234 falling off, which is beneficial to improving the reliability of the shell 23 during use.

[0111] According to some embodiments of the present application, the material of the first insulating member 234 has a polar group.

[0112] Among them, the material of the first insulating member 234 has a polar group, that is, after the first insulating member 234 is processed, a polar group will be formed in the material of the first insulating member 234, and the polar group can be one or more of -COOH, -OH, -CHO, -NH2 or -SH.

[0113] Exemplarily, when the material of the first insulating member 234 is polypropylene, grafting modification (for example, maleic anhydride grafting modification) can be performed at the plastic particle level so that the single functional group methyl (-CH3) in the original polypropylene can be replaced with polar functional groups such as -OH and -COOH, so that the material of the first insulating member 234 has polar groups.

[0114] The first insulating member 234 is made of a material having polar groups, that is, the first insulating member 234 has polar groups therein, and the polar groups can effectively improve the bonding firmness between the first insulating member 234 and the first wall 232 of the shell 23, thereby further improving the bonding strength between the first insulating member 234 and the first wall 232.

[0115] According to some embodiments of this application, see Figure 4 As shown, the shell 23 also includes a second insulating member 237, which is arranged in the accommodating space 235 along the circumference of the second wall 233, and the second insulating member 237 is thermally composited with the second wall 233, and is used to separate the second wall 233 and the electrode assembly 21.

[0116] The second insulating member 237 is thermally compounded on the second wall 233 of the shell 23, and the second insulating member 237 is arranged along the circumference of the second wall 233, that is, the second insulating member 237 is arranged on the second wall 233 along the circumference of the second wall 233, and the second insulating member 237 is combined with the second wall 233 of the shell 23 after hot melting, so that the second insulating member 237 is hot-melted and bonded to the second wall 233, so that there is no need to set an adhesive between the second insulating member 237 and the second wall 233. The second insulating member 237 is used to separate the second wall 233 and the electrode assembly 21, so as to achieve insulation isolation between the electrode assembly 21 and the second wall 233 of the shell 23, that is, the electrical isolation between the electrode assembly 21 and the second wall 233 of the shell 23 is achieved by the second insulating member 237.

[0117] Optionally, the second insulating member 237 is a film structure of an organic polymer insulating material, and the second insulating member 237 is laid on the second wall 233 of the shell 23 along the circumference of the second wall 233. The second insulating member 237 has good acid resistance and alkali resistance, and can withstand strong acids with a pH value of less than 7 and strong alkalis with a pH value of greater than 12. Exemplarily, the material of the second insulating member 237 can be polypropylene or polyethylene terephthalate.

[0118] By thermally bonding the second insulating member 237 to the second wall 233, the bonding strength between the second insulating member 237 and the second wall 233 can be improved, so that when vibration occurs during the use of the battery cell 20 or gas is generated inside the battery cell 20 to cause the shell 23 to expand, the risk of the second insulating member 237 and the second wall 233 falling off or generating a gap can be reduced. Therefore, the shell 23 with such a structure can achieve insulation isolation between the electrode assembly 21 and the second wall 233 of the shell 23, instead of setting a spacer for isolation in the shell 23. The shell 23 and the insulating film of the electrode assembly 21 can reduce the electrolyte from being free between the second wall 233 and the insulating film, so as to alleviate the phenomenon that the electrolyte in the shell 23 is blocked by the insulating film when it refluxes and causes poor wetting of the electrode assembly 21, which is beneficial to improving the performance of the battery cell 20 with such a shell 23. On the other hand, it can play a certain protective role on the shell 23, effectively reducing the direct contact between the electrolyte and the second wall 233 of the shell 23, which is beneficial to improving the corrosion resistance and leakage resistance of the shell 23, and thus can increase the service life of the battery cell 20. In addition, during the production process of the battery cell 20, the process of setting an insulating film on the outer peripheral side of the electrode assembly 21 is eliminated, and the second insulating member 237 can be thermally composited to the second wall 233 of the shell 23 in the production branch line of the shell 23 to complete the covering process of the second insulating member 237, so that the shell 23 can be produced in parallel with the battery cell 20. That is to say, when the shell 23 enters the production assembly line of the battery cell 20, the covering process of the second insulating member 237 has been completed, so that the covering process of the second insulating member 237 will not occupy the production rhythm of the battery cell 20, which is beneficial to improve the production efficiency of the battery cell 20.

[0119] According to some embodiments of the present application, referring to Figure 4 , and please refer to Figure 7 , Figure 7 for Figure 4 The enlarged view of the part of the housing 23 at C is shown. In the preset direction X, the distance between the edge of the second insulating member 237 close to the opening 231 and the opening 231 is 1-8 mm.

[0120] In the preset direction X, the distance between the edge of the second insulating member 237 close to the opening 231 and the opening 231 is 1-8 mm (eg Figure 7 As shown, Figure 7 In the figure, d is the distance between the edge of the second insulating member 237 close to the opening 231 and the opening 231), that is, there is a distance between the edge of the second insulating member 237 and the edge of the second wall 233, so as to facilitate the installation of the end cover 22 when the end cover 22 is covered on the opening 231 of the shell 23.

[0121] By arranging the edge of the second insulating member 237 close to the opening 231 of the shell 23 at a distance from the opening 231, that is, the edge of the second insulating member 237 close to the opening 231 of the shell 23 is spaced apart from the opening 231, that is, there is a certain distance between the edge of the second insulating member 237 close to the opening 231 of the shell 23, so as to reduce the influence and interference of the second insulating member 237 on the end cover 22 of the battery cell 20 when it is covered on the opening 231 of the shell 23, thereby ensuring the reliability of the connection between the end cover 22 and the shell 23.

[0122] According to some embodiments of the present application, the thickness of the second insulating member 237 is 0.03-0.5 mm.

[0123] By setting the thickness of the second insulating member 237 between 0.03 mm and 0.5 mm, on the one hand, the phenomenon of poor insulation effect and short service life of the second insulating member 237 caused by the second insulating member 237 being too thin can be reduced, so as to ensure the insulation effect and reliability of the second insulating member 237. On the other hand, the impact of the excessive thickness of the second insulating member 237 on the capacity of the accommodating space 235 of the shell 23 can be alleviated, so as to ensure the energy density of the battery cell 20 having such a shell 23.

[0124] According to some embodiments of the present application, referring to Figure 4 , and please refer to Figure 8 , Figure 8 for Figure 4 The second insulating member 237 has a plurality of second pores that allow at least part of the gas to pass through and prevent the electrolyte from passing through. The second wall 233 is provided with a second vent hole 2331 for at least part of the gas to pass through.

[0125] Among them, the second insulating member 237 has multiple second pores that allow at least part of the gas to pass through and prevent the electrolyte from passing through, that is, the material of the second insulating member 237 forms multiple second pores, and the second pores can allow part of the gas in the shell 23 to pass through, but can prevent the electrolyte in the shell 23 from passing through, so that the second insulating member 237 has selective permeability.

[0126] Optionally, the number of the second vent hole 2331 formed on the second wall 233 may be one or more. Figure 6 In the embodiment, there is one second vent hole 2331 formed on the second wall 233. In other embodiments, there may be two, three, four, etc. second vent holes 2331.

[0127] The second insulating member 237 has a plurality of second pores, which can allow some gas to pass through and prevent electrolyte from passing through. By opening a second vent hole 2331 on the second wall 233, the gas in the accommodating space 235 of the shell 23 can pass through the second insulating member 237 and then be discharged to the outside of the shell 23 through the second vent hole 2331, thereby alleviating the flatulence or bulging phenomenon of the battery cell 20 having such a shell 23, which is beneficial to improving the safety and service life of the battery cell 20.

[0128] Furthermore, the pore size of the second pore is 0.4-189 nm.

[0129] During the use of the battery cell 20, the main gases generated in the housing 23 are hydrogen, carbon monoxide, carbon dioxide and methane, etc. The kinetic diameter of hydrogen is 0.289nm, the kinetic diameter of carbon monoxide is 0.376nm, the kinetic diameter of carbon dioxide is 0.33nm, and the kinetic diameter of methane is 0.38nm. The kinetic diameters of these gases are all less than 0.4nm, so that the second insulating member 237 can allow these gases to pass through. Among them, the molecular diameter of the electrolyte in the housing 23 is less than 189nm, so that liquid water and solvents cannot pass through the second insulating member 237.

[0130] By setting the pore size of the second pore to between 0.4nm and 189nm, the pore size of the second pore is larger than the diameter of some gas molecules and smaller than the diameter of liquid molecules of the electrolyte, thereby achieving the second insulating member 237 being able to allow some gas to pass through but preventing the electrolyte from passing through.

[0131] According to some embodiments of this application, please refer to Fig. 9 and Fig.10 , Fig. 9 A cross-sectional view of a battery cell 20 provided in some embodiments of the present application, Fig.10 for Fig. 9 The second insulating member 237 is overlapped and thermally composited at both ends of the second wall 233 in the circumferential direction to form an overlapped region 2371 .

[0132] The second insulating member 237 overlaps and is thermally composited at both ends of the second wall 233 in the circumferential direction, that is, after the second insulating member 237 is thermally composited on the second wall 233 along the circumferential direction of the second wall 233, the two free ends of the second insulating member 237 in the circumferential direction of the second wall 233 overlap and are thermally composited. It should be noted that the thermally composite connection of the second insulating member 237 at both ends of the second wall 233 in the circumferential direction means that both ends of the second insulating member 237 are hot-melted and then bonded together.

[0133] Optionally, the second insulating member 237 may be one or more. Fig. 9 In the embodiment, there is one second insulating member 237, and the first and last ends of the second insulating member 237 in the circumferential direction of the second wall 233 overlap each other and are then thermally composited and connected. Of course, in other embodiments, there may be multiple second insulating members 237, and the multiple second insulating members 237 overlap each other in sequence along the circumferential direction of the second wall 233 and are then thermally composited and connected.

[0134] The second insulating member 237 is laid on the second wall 233 along the circumference of the second wall 233, and the head and tail ends of the second insulating member 237 in the circumference of the second wall 233 are overlapped with each other and then thermally composited. The shell 23 with such a structure can, on the one hand, improve the connection strength of the head and tail ends of the second insulating member 237, and on the other hand, alleviate the risk of gaps in the second insulating member 237, so as to reduce the phenomenon that the electrolyte in the shell 23 enters between the second insulating member 237 and the second wall 233 through the gaps in the second insulating member 237, thereby helping to improve the protective effect of the second insulating member 237 on the shell 23.

[0135] According to some embodiments of this application, please continue to refer to Fig. 9 and Fig.10 As shown, the second wall 233 includes a plurality of walls connected end to end in sequence along its circumferential direction, and a corner area 2332 is formed at the connection between each two adjacent walls, and the overlapping area 2371 is arranged corresponding to the corner area 2332.

[0136] The second wall 233 includes a plurality of walls connected end to end in sequence along its circumferential direction, that is, the second wall 233 is a polygonal structure, that is, the housing 23 is a polygonal structure. Fig. 9 In the figure, the second wall 233 includes four walls, which are connected end to end in sequence to form a shell 23 of a rectangular structure, so that the overlapping area 2371 of the second insulating member 237 is correspondingly arranged at the corner area 2332 of the second wall 233, that is, at the corner of the shell 23 of the rectangular structure.

[0137] Optionally, when the overlapping area 2371 is provided at the corner area 2332 of the second wall 233, the overlapping area 2371 may extend from the corner area 2332 of the second wall 233 toward two walls adjacent to the corner area 2332 along the circumferential direction of the second wall 233. Fig. 9 and Fig.10 In the embodiment, the overlapping area 2371 extends from the corner area 2332 of the second wall 233 to a wall in the width direction of the second wall 233 along the circumference of the second wall 233. In other embodiments, such as Fig.11 and 12 As shown, Fig.11The cross-sectional view of the battery cell 20 provided in some other embodiments of the present application is as follows. Fig.12 for Fig.11 In the partial enlarged view of the battery cell 20 at F shown in the figure, the overlapping area 2371 extends from the corner area 2332 of the second wall 233 to a wall in the length direction of the second wall 233 along the circumference of the second wall 233 .

[0138] It should be noted that the length of the overlapping area 2371 in the circumferential direction of the second wall 233 is less than or equal to half the thickness of a single electrode assembly 21 .

[0139] Since the electrode assembly 21 in the shell 23 cannot be completely fitted in the corner area 2332 of the second wall 233, there is a gap between the electrode assembly 21 and the corner area 2332 of the second wall 233, and the overlapping area 2371 is the area protruding from the second wall 233 after the head and tail ends of the second insulating member 237 overlap with each other. Therefore, by setting the overlapping area 2371 of the second insulating member 237 corresponding to the corner area 2332 of the second wall 233, on the one hand, the collision between the electrode assembly 21 and the overlapping area 2371 can be reduced, and on the other hand, the influence of the overlapping area 2371 on the capacity of the electrode assembly 21 in the accommodating space 235 can be effectively reduced.

[0140] According to some embodiments of the present application, referring to Fig.13 , Fig.13 The schematic diagram of the structure of the second wall 233 provided in some embodiments of the present application is as follows: The second wall 233 is formed with a second nano-plating layer 2333 , and the second insulating member 237 is thermally compounded with the second nano-plating layer 2333 .

[0141] The second wall 233 is provided with a second nano-plating layer 2333, that is, the inner circumference of the second wall 233 is nano-processed to form the second nano-plating layer 2333 on the second wall 233. It should be noted that if the second vent hole 2331 needs to be formed on the second wall 233, the second vent hole 2331 needs to be processed on the second wall 233 first, and then the second wall 233 needs to be nano-processed.

[0142] Optionally, the second nano-plating layer 2333 may be partially formed on the second wall 233 , or may be entirely formed on the second wall 233 .

[0143] By forming a second nano-coating 2333 on the second wall 233 and thermally compounding the second insulating member 237 on the second nano-coating 2333 of the second wall 233, the bonding strength between the second insulating member 237 and the second wall 233 can be further improved, thereby reducing the risk of the second insulating member 237 falling off, which is beneficial to improving the reliability of the shell 23 during use.

[0144] For further information, please see Fig.13 The second nano-plating layer 2333 is an annular structure extending along the circumference of the second wall 233. In the preset direction X, the second nano-plating layer 2333 extends from the edge of the second insulating member 237 close to the opening 231 toward the direction facing the first wall 232.

[0145] In which, in the preset direction X, the second nano-coating 2333 extends from the edge of the second insulating member 237 close to the opening 231 toward the direction facing the first wall 232, that is, the area on the second wall 233 that is thermally composited with the edge of the second insulating member 237 is preferentially nano-treated so that the second nano-coating 2333 forms an annular structure extending circumferentially along the second wall 233.

[0146] In some embodiments, Fig.13 As shown, the corner area 2332 of the second wall 233 is also formed with a nano-plating layer to ensure the bonding strength between the overlapping area 2371 of the second insulating member 237 and the second wall 233. Of course, the above structures are all local nano-processing on the second wall 233, so that the second nano-plating layer 2333 is locally formed on the second wall 233. In a preferred embodiment, in order to ensure the bonding strength between the second insulating member 237 and the second wall 233, the entire inner circumference of the second wall 233 can be nano-processed to form the second nano-plating layer 2333 on the entire inner circumference of the second wall 233.

[0147] By setting the second nano-coating 2333 as an annular structure extending along the circumference of the second wall 233, and the second nano-coating 2333 extending along the preset direction X from the edge of the second insulating member 237 toward the direction facing the first wall 232, it is ensured that the second nano-coating 2333 is formed in the area where the edge of the second insulating member 237 and the second wall 233 are thermally compounded, thereby improving the bonding strength between the edge of the second insulating member 237 and the second wall 233, and further effectively alleviating the phenomenon of electrolyte penetrating from the edge of the second insulating member 237 into between the second insulating member 237 and the second wall 233.

[0148] According to some embodiments of the present application, the material of the second insulating member 237 has a polar group.

[0149] Among them, the material of the second insulating member 237 has a polar group, that is, after the second insulating member 237 is processed, a polar group will be formed in the material of the second insulating member 237, and the polar group can be one or more of -COOH, -OH, -CHO, -NH2 or -SH.

[0150] Exemplarily, when the material of the second insulating member 237 is polypropylene, grafting modification (for example, maleic anhydride grafting modification) can be performed at the plastic particle level so that the single functional group methyl (-CH3) in the original polypropylene can be replaced with polar functional groups such as -OH and -COOH, so that the material of the second insulating member 237 has polar groups.

[0151] The second insulating member 237 is made of a material having polar groups, that is, the second insulating member 237 has polar groups therein. The polar groups can effectively improve the bonding strength between the second insulating member 237 and the second wall 233 of the shell 23, thereby further improving the bonding strength between the second insulating member 237 and the second wall 233.

[0152] According to some embodiments of this application, see Figure 4 and Figure 5 As shown, the first insulating member 234 and the second insulating member 237 are thermally compositely connected at one end away from the opening 231 in the preset direction X.

[0153] The first insulating member 234 and the second insulating member 237 are thermally composited and connected, that is, the first insulating member 234 and the second insulating member 237 are hot-melted and bonded to each other.

[0154] Optionally, in other embodiments, the first insulating member 234 and the second insulating member 237 may also be an integrated structure.

[0155] By thermally composite-connecting the first insulating member 234 and one end of the second insulating member 237, on the one hand, the connection strength between the first insulating member 234 and the second insulating member 237 can be improved, and on the other hand, the phenomenon of a gap between the first insulating member 234 and the second insulating member 237 can be reduced, thereby reducing the risk of electrolyte infiltration from the gap between the first insulating member 234 and the second insulating member 237.

[0156] According to some embodiments of the present application, the present application further provides a battery cell 20, including an electrode assembly 21, an end cap 22 and a housing 23 of any of the above solutions. The electrode assembly 21 is placed in the housing 23, and the end cap 22 covers the opening 231 of the housing 23.

[0157] Exemplarily, the end cover 22 is welded to the housing 23 after covering the opening 231 of the housing 23 .

[0158] According to some embodiments of the present application, the present application further provides a battery 100 , including a housing 10 and a battery cell 20 of any of the above solutions, wherein the housing 10 is used to accommodate the battery cell 20 .

[0159] According to some embodiments of the present application, the present application further provides an electrical device, comprising a battery 100 according to any of the above schemes, and the battery 100 is used to provide electrical energy to the electrical device.

[0160] The power-consuming device may be any of the aforementioned devices or systems using the battery 100 .

[0161] According to some embodiments of the present application, see Figure 4-Figure 10 As shown, the present application provides a shell 23, the shell 23 includes a first wall 232, a second wall 233, a first insulating member 234 and a second insulating member 237, a first nano-coating layer is formed on the first wall 232, a second nano-coating layer 2333 is formed on the second wall 233, the second wall 233 is arranged around the first wall 232, the second wall 233 has a plurality of corner areas 2332, one end of the second wall 233 in a preset direction X is connected to the first wall 232 and forms a chamfer 236, the other end of the second wall 233 in the preset direction X forms an opening 231, the second wall 233 and the first wall 232 jointly define a accommodating space 235 for accommodating the electrode assembly 21. The first insulating member 234 is thermally composited to the first wall 232. The thickness of the first insulating member 234 in the preset direction X is greater than the chamfer 236 between the first wall 232 and the second wall 233. The first insulating member 234 has a plurality of first pores with a pore size of 0.4-189 nm. Correspondingly, a first vent hole 2321 for ventilation is provided on the first wall 232. The second insulating member 237 is thermally composited to the second wall 233 along the circumference of the second wall 233. The two end portions of the second insulating member 237 overlap each other and are thermally composited to form an overlapping region 2371. The overlapping region 2371 is correspondingly arranged at the corner region 2332 of the second wall 233. The second insulating member 237 has a plurality of second pores with a pore size of 0.4-189 nm. Correspondingly, a second vent hole 2331 for ventilation is provided on the second wall 233.

[0162] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0163] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A shell for accommodating an electrode assembly, characterized in that: include: First wall; a second wall, the second wall being arranged around the first wall, one end of the second wall in a preset direction being connected to the first wall, the other end of the second wall in the preset direction forming an opening, and the second wall and the first wall jointly defining an accommodation space for accommodating the electrode assembly; as well as a first insulating member, the first insulating member being disposed in the accommodation space, the first insulating member being thermally bonded to the first wall, and the first insulating member being used to separate the first wall and the electrode assembly; The first insulating member has a plurality of first pores that allow at least part of the gas to pass through and prevent the electrolyte from passing through, and the first wall is provided with a first vent hole for allowing at least part of the gas to pass through.

2. The housing according to claim 1, characterized in that A chamfer is formed at a connection between the first wall and the second wall; In the preset direction, the thickness of the first insulating member is greater than the height of the chamfer.

3. The housing according to claim 2, characterized in that: The thickness of the first insulating member is 0.1-0.8 mm.

4. The housing according to claim 1, characterized in that The pore size of the first pore is 0.4-189 nm.

5. The housing according to claim 1, characterized in that A first nano-plating layer is formed on the first wall, and the first insulating member is thermally composited with the first nano-plating layer.

6. The housing according to claim 1, characterized in that The material of the first insulating member has a polar group.

7. The housing according to any one of claims 1 to 6, characterized in that: The housing further comprises: A second insulating member is disposed in the accommodation space along the circumference of the second wall, the second insulating member is thermally composited to the second wall, and the second insulating member is used to separate the second wall and the electrode assembly.

8. The housing according to claim 7, characterized in that In the preset direction, a distance between an edge of the second insulating member close to the opening and the opening is 1-8 mm.

9. The housing according to claim 7, characterized in that: The thickness of the second insulating member is 0.03-0.5 mm.

10. The housing according to claim 7, characterized in that The second insulating member has a plurality of second pores that allow at least part of the gas to pass through and prevent the electrolyte from passing through; The second wall is provided with a second vent hole for allowing at least part of the gas to pass through.

11. The housing according to claim 10, characterized in that The pore size of the second pore is 0.4-189 nm.

12. The housing according to claim 7, characterized in that The second insulating member overlaps at both ends of the second wall in the circumferential direction and is thermally composited and connected to form an overlapping area.

13. The housing according to claim 12, characterized in that The second wall includes a plurality of walls connected end to end in sequence along its circumferential direction, and the connection between each two adjacent walls forms a corner area; The overlapping area is arranged corresponding to the corner area.

14. The housing according to claim 7, characterized in that A second nano-plating layer is formed on the second wall, and the second insulating member is thermally composited with the second nano-plating layer.

15. The housing according to claim 14, characterized in that The second nano-plating layer is an annular structure extending along the circumference of the second wall; In the preset direction, the second nano-plating layer extends from an edge of the second insulating member close to the opening toward a direction facing the first wall.

16. The housing according to claim 7, characterized in that The material of the second insulating member has a polar group.

17. The housing according to claim 7, characterized in that The first insulating member and the second insulating member are thermally compositely connected at one end away from the opening in the preset direction.

18. A battery cell, characterized in that: include: Electrode assembly; End caps; as well as The shell according to any one of claims 1 to 17, wherein the electrode assembly is placed in the shell, and the end cover covers the opening of the shell.

19. A battery, characterized in that: include: The battery cell as claimed in claim 18; as well as A box body is used to accommodate the battery cells.

20. An electrical device, characterized in that: Comprising a battery as claimed in claim 19, the battery is used to provide electrical energy.

Images