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. Among them, the shell includes a shell body and an insulating member. An opening is formed at one end of the shell body in a preset direction, and the shell body is used to accommodate an electrode assembly. The insulating member is coated on the outside of the shell body and thermally composited to the outer surface of the shell body. On the one hand, a shell with such a structure can effectively improve the problem of failure of the bonding force between the insulating member and the shell body during long-term use, thereby helping to reduce the risk of falling off or generating a gap between the insulating member and the shell body, so as to improve the reliability of the battery cell with such a shell. On the other hand, the insulating member can play a role in sealing and protecting the shell body, reducing the risk of corrosion or leakage of the shell due to the influence of the external environment, so that the shell has good anti-corrosion and anti-leakage functions, which is conducive to improving the service life of the battery cell with such a shell.

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 membrane, which is then loaded into a shell, injected with electrolyte, and finally covered with an end cover. In order to achieve insulation between the battery shell and the external environment, in the prior art, a blue film is bonded to the outer surface of the shell to achieve the insulation function of the shell. However, the battery cell using this structure has a short service life and low production efficiency. 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 service life and production efficiency of the battery cell.

[0004] In the first aspect, an embodiment of the present application provides a shell for accommodating an electrode assembly, the shell comprising a shell body and an insulating member; an opening is formed at one end of the shell body in a preset direction, and the shell body is used to accommodate the electrode assembly; the insulating member is coated on the outside of the shell body and thermally composited to the outer surface of the shell body.

[0005] In the above technical solution, an insulating part for separating the outer surface of the shell body and the external environment is provided on the outer side of the shell body to achieve insulation isolation between the shell and the external environment. By thermally compounding the insulating part to the outer surface of the shell body, the bonding strength and structural strength between the insulating part and the shell body can be improved. On the one hand, a shell with such a structure can effectively improve the problem of failure of bonding between the insulating part and the shell body during long-term use, thereby helping to reduce the risk of falling off or generating a gap between the insulating part and the shell body, so as to improve the reliability of the battery cell with such a shell. On the other hand, the insulating part can play a role of sealing and protecting the shell body, reducing the risk of corrosion or leakage of the shell due to the influence of the external environment, so that the shell has good anti-corrosion and anti-leakage functions, which is beneficial to improve the service life of the battery cell with such a shell. In addition, in the production process of battery cells, the process of bonding the blue film on the outer surface of the shell during the assembly of the battery cells is cancelled. The insulating parts can be thermally composited to the outer surface of the shell body in the production branch line of the shell to complete the covering process of the insulating parts, so that the shell can be produced in parallel with the battery cells. That is to say, when the shell enters the production assembly line of the battery cells, the covering process of the insulating parts has been completed, so that the covering process of the insulating parts will not occupy the production rhythm of the battery cells, which is beneficial to improve the production efficiency of the battery cells.

[0006] In some embodiments, along a preset direction, a distance between an edge of the insulating member close to the opening and the opening is 2-6 mm.

[0007] In the above technical solution, by setting a distance between the edge of the insulating member close to the opening in a preset direction and the opening, that is, the insulating member is spaced apart from the opening by the edge of the opening close to the opening in the preset direction, the influence and interference of the insulating member on the end cover of the battery cell having such a shell when it is covered at the opening of the shell body and connected to the shell body is reduced, which is beneficial to ensure the connection reliability between the end cover and the shell.

[0008] In some embodiments, the thickness of the insulating member is 0.05-0.3 mm.

[0009] In the above technical solution, by setting the thickness of the insulating part between 0.05mm and 0.3mm, on the one hand, the problem of poor insulation and protection effects of the insulating part on the shell body caused by the insulating part being too thin can be reduced, and the service life and reliability of the insulating part can be improved. On the other hand, the problem of excessive space occupied by the shell caused by the insulating part being too thick can be alleviated.

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

[0011] In the above technical solution, the insulating member has a plurality of pores, which can allow a portion of gas to pass through and can prevent the electrolyte from passing through. Thus, by opening ventilation holes on the shell body for ventilation, a portion of the gas in the shell body can pass through the ventilation holes and then pass through the insulating member to the outside of the shell body, thereby alleviating the expansion or bloating phenomenon of the battery cell having such a shell, which is beneficial to improving the safety and service life of the battery cell.

[0012] In some embodiments, the pores have a pore size of 0.4-189 nm.

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

[0014] In some embodiments, the shell body includes a bottom wall and a side wall, the side wall is arranged around the bottom wall, one end of the side wall in a preset direction is connected to the bottom wall, and the other end of the side wall in the preset direction forms an opening, and the side wall and the bottom wall jointly define a accommodating space for accommodating the electrode assembly; the insulating part includes a first insulator and a second insulator, the first insulator is arranged on the outer side of the bottom wall, and the second insulator is arranged on the outer side of the side wall along the circumference of the side wall; wherein the first insulator is thermally composited to the outer surface of the bottom wall; and / or the second insulator is thermally composited to the outer surface of the side wall.

[0015] In the above technical solution, the shell body has a bottom wall and a side wall. By surrounding the side wall on one side of the bottom wall, the side wall and the bottom wall together define a storage space for accommodating the electrode assembly, and the structure is simple and easy to implement. In addition, by setting the insulating member as two parts, a first insulator and a second insulator, the first insulator is used to thermally composite the outer surface of the bottom wall, and the second insulator is used to thermally composite the outer surface of the side wall along the circumference of the side wall, so that the insulating member is coated on the outer side of the shell body, the shell adopting this structure is easy to manufacture, which is conducive to reducing the difficulty of processing the shell.

[0016] In some embodiments, the first and last ends of the second insulator in the circumferential direction of the side wall are overlapped and thermally composited to form an overlapped area.

[0017] In the above technical solution, the second insulator is arranged on the outer surface of the side wall along the circumference of the side wall, and the head and tail ends of the second insulator in the circumference of the side wall are overlapped with each other and then thermally composited. This structure is beneficial to improving the connection strength between the head and tail ends of the second insulator, and can reduce the risk of gaps being generated after the second insulator is thermally composited to the outer surface of the side wall, thereby alleviating the phenomenon that substances in the external environment enter between the second insulator and the outer surface of the shell body through the gaps in the second insulator and cause corrosion of the shell body, which is beneficial to improving the corrosion resistance of the shell.

[0018] In some embodiments, the side wall includes two first walls and two second walls; one first wall, one second wall, another first wall and another second wall are connected end to end in sequence, the two first walls are opposite and spaced apart, the two second walls are opposite and spaced apart, and the area of ​​the first wall is greater than the area of ​​the second wall; wherein the overlapping area is arranged corresponding to the second wall.

[0019] In the above technical solution, the side wall has two first walls and two second walls, and the two first walls and the two second walls are arranged opposite to each other and connected end to end to form a shell structure of a quadrilateral structure. Since the end portions of the second insulator will protrude from the outer surface of the shell body after overlapping each other, by setting the overlapping area of ​​the second insulator on the second wall with a smaller area in the side wall, the use of this structure can reduce the risk of cracks in the overlapping area caused by the large deformation of the first wall with a larger area during the expansion or contraction of the battery cell, thereby facilitating the long-term use reliability of the insulating member, and on the other hand, when multiple battery cells with such a shell are assembled together, it is conducive to alleviating the risk of increased deformation of the battery cell shell caused by the influence of the overlapping area when a collision occurs between the battery cells.

[0020] In some embodiments, the outer surface of the bottom wall and the outer surface of the side wall are both formed with a nano-plating layer.

[0021] In the above technical solution, nano-plating layers are formed on the outer surface of the bottom wall and the outer surface of the side wall, and the insulating member is thermally compounded on the nano-plating layers, so that the bonding strength between the insulating member and the outer surface of the shell body can be further improved to reduce the risk of the insulating member falling off or generating a gap, thereby improving the reliability of the shell. In addition, after improving the bonding strength between the insulating member and the bottom wall, the phenomenon of the gap between the insulating member and the bottom wall can be reduced, so that the battery cell with such a shell can transfer heat through the bottom wall, thereby reducing the influence of the gap between the insulating member and the bottom wall on the heat transfer, thereby facilitating the improvement of the heat dissipation effect of the battery cell.

[0022] In some embodiments, the side wall includes two first walls and two second walls; one first wall, one second wall, another first wall and another second wall are connected end to end in sequence, the two first walls are opposite to each other and arranged at intervals, the two second walls are opposite to each other and arranged at intervals, and the area of ​​the first wall is greater than that of the second wall; wherein a nano-plating layer is formed on the outer surface of the first wall.

[0023] In the above technical solution, the side wall has two first walls and two second walls, and the two first walls and the two second walls are arranged opposite to each other and connected end to end to form a shell structure of a quadrilateral structure. Since the first wall with a larger area in the side wall has a larger deformation during the expansion or contraction of the battery cell, the bonding strength between the second insulator and the first wall is improved by forming a nano-plating layer on the outer surface of the first wall, which is conducive to reducing the risk of the second insulator disposed on the outer surface of the first wall falling off or having a gap due to the large deformation of the first wall.

[0024] In some embodiments, an end of the second insulator away from the opening in a preset direction is thermally compositely connected to the first insulator.

[0025] In the above technical solution, by thermally composite-connecting the first insulator and one end of the second insulator, the insulating member with this structure can, on the one hand, improve the connection strength between the first insulator and the second insulator, and on the other hand, reduce the phenomenon of the existence of a gap between the first insulator and the second insulator, thereby helping to reduce the risk of substances from the external environment penetrating from the gap between the first insulator and the second insulator.

[0026] In some embodiments, the material of the insulating element includes polar groups.

[0027] In the above technical solution, an insulating part made of a material having a polar group is used, that is, the insulating part has a polar group. The polar group can effectively improve the bonding strength between the insulating part and the outer surface of the shell body, thereby facilitating further improving the bonding strength between the insulating part and the shell body.

[0028] 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 body; and the end cover covers the opening of the shell body.

[0029] In some embodiments, the end cover is welded to one end of the shell body in a preset direction and forms a weld mark extending along the circumference of the opening; the battery cell also includes a protective member, which covers the weld mark along the circumference of the opening.

[0030] In the above technical solution, the battery cell is also provided with a protective member, which is arranged on the outer side of the shell along the circumference of the opening, and the protective member is covered on the outer side of the weld mark formed between the end cover and the shell body along the circumference of the opening to separate the weld mark from the external environment, so that the connection between the end cover and the shell body is insulated and isolated from the external environment, which is beneficial to enhance the protection of the battery cell.

[0031] In some embodiments, along a preset direction, an edge of the insulating member close to the opening is spaced apart from the weld mark; and at least a portion of the protective member in the preset direction is wrapped around the outer side of the insulating member along the circumference of the opening.

[0032] In the above technical solution, the protective member is wrapped around the outer side of the insulating member along the circumference of the opening at least partially in the preset direction, that is, since there is a certain distance between the edge of the insulating member close to the opening in the preset direction and the weld mark, after the protective member is wrapped around the weld mark along the circumference of the opening, one end of the protective member close to the insulating member in the preset direction overlaps with one end of the insulating member close to the opening in the preset direction, so that the protective member can wrap and cover the edge of the insulating member close to the opening in the preset direction. The battery cell adopting this structure can, on the one hand, reduce the risk of substances from the external environment entering between the insulating member and the outer surface of the shell body through the edge of the insulating member, and on the other hand, the protective member can strengthen the bonding strength between the edge of the insulating member close to the opening in the preset direction and the outer surface of the shell body, which is conducive to alleviating the risk of the edge of the insulating member falling off or generating gaps due to failure of bonding force during later use.

[0033] 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.

[0034] 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

[0035] 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.

[0036] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0037] Figure 2 An exploded view of the structure of a battery provided in some embodiments of the present application;

[0038] Figure 3 An exploded view of the structure of a battery cell provided in some embodiments of the present application;

[0039] Figure 4 A cross-sectional view of a housing provided for some embodiments of the present application;

[0040] Figure 5 for Figure 4 A partial enlarged view of the shell at A shown;

[0041] Figure 6 for Figure 4 A partial enlarged view of the B portion of the shell shown;

[0042] Figure 7 for Figure 4 A partial enlarged view of the C portion of the shell shown;

[0043] Figure 8 A cross-sectional view of a housing provided for some embodiments of the present application;

[0044] Fig. 9 for Figure 8 A partial enlarged view of a portion D of the shell shown;

[0045] Fig.10 A cross-sectional view of a battery cell provided for some embodiments of the present application;

[0046] Fig.11 for Fig.10 A partial enlarged view of E of the battery cell shown.

[0047] Icons: 1000-vehicle; 100-battery; 10-casing; 11-first part; 12-second part; 20-battery cell; 21-shell; 211-opening; 212-shell body; 2121-vent; 2122-bottom wall; 2123-side wall; 2123a-first wall; 2123b-second wall; 2124-accommodating space; 213-insulating member; 2131-first insulator; 2132-second insulator; 2132a-overlapping area; 22-electrode assembly; 23-end cover; 24-positive electrode terminal; 25-negative electrode terminal; 26-pressure relief mechanism; 27-protective member; 28-weld stamp; 200-controller; 300-motor; X-preset direction. DETAILED DESCRIPTION

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] The term "plurality" used in the present application refers to two or more (including two).

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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 the safety and service life of batteries.

[0060] The inventors found that in order to improve the safety of battery use and reduce the safety hazards such as leakage in the shell of the battery cell, in the prior art, a blue film is usually bonded to the outer surface of the shell of the battery cell to achieve the insulation function of the shell, thereby improving the safety of the battery cell during use. However, in the battery cell of this structure, the blue film used for insulation is coated on the outer surface of the shell by glue bonding, the bonding force is not strong enough, and the shear force is also weak. When the battery cell is assembled in the battery box, the outer surface of the battery cell needs to be bonded to the adjacent battery cell, the inner surface of the box, etc. by glue, so that when the battery cell is subjected to vibration or other impact conditions during use, the blue film is very easy to fall off or produce gaps, and the battery cell will expand and shrink during long-term use, which is easy to cause the blue film with weak bonding force to fail to bond, thereby reducing the structural strength and reliability of the battery cell, which is not conducive to improving the service life of the battery cell.

[0061] Based on the above considerations, in order to solve the problem of short service life of battery cells, the inventors have designed a shell after in-depth research. The shell includes a shell body and an insulating member. The shell body is used to accommodate the electrode assembly, and the insulating member is coated on the outside of the shell body and thermally composited to the outer surface of the shell body.

[0062] A shell adopting this structure can improve the bonding strength and structural strength between the insulating part and the shell body. On the one hand, it can effectively improve the problem of failure of bonding between the insulating part and the shell body during long-term use, thereby reducing the risk of falling off or generating a gap between the insulating part and the shell body, so as to improve the reliability of the battery cell with such a shell. On the other hand, the insulating part can seal and protect the shell body, reducing the risk of corrosion or leakage of the shell due to the influence of the external environment, so that the shell has good anti-corrosion and anti-leakage functions, which is beneficial to improve the service life of the battery cell with such a shell.

[0063] In addition, in the production process of battery cells, the process of bonding the blue film on the outer surface of the shell during the assembly of the battery cells is cancelled. The insulating parts can be thermally composited to the outer surface of the shell body in the production branch line of the shell to complete the covering process of the insulating parts, so that the shell can be produced in parallel with the battery cells. That is to say, when the shell enters the production assembly line of the battery cells, the covering process of the insulating parts has been completed, so that the covering process of the insulating parts will not occupy the production rhythm of the battery cells, which is beneficial to improve the production efficiency of the battery cells.

[0064] 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 reduced structural strength and reliability of the battery cells in the later use process, so as to increase the service life of the battery cells.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] Please refer to Figure 3 , Figure 3 The structure of the battery cell 20 provided in some embodiments of the present application is exploded. The battery cell 20 includes a housing 21, an electrode assembly 22 and an end cap 23. The housing 21 is used to accommodate the electrode assembly 22. One end of the housing 21 has an opening 211. The end cap 23 is used to cover the opening 211 of the housing 21.

[0073] The housing 21 can also be used to contain electrolytes, such as electrolytes. The housing 21 can be in various structural forms. The housing 21 can also be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc.

[0074] In some embodiments, one end of the shell 21 has an opening 211, that is, the shell 21 is a hollow structure with one end open, and the end cover 23 covers the opening 211 of the shell 21 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 22 and the electrolyte.

[0075] When assembling the battery cell 20 , the electrode assembly 22 may be placed in the housing 21 first, and the housing 21 may be filled with electrolyte, and then the end cap 23 may be closed on the opening 211 of the housing 21 .

[0076] The shell 21 can be in various shapes, such as a cylinder, a cuboid, etc. The shape of the shell 21 can be determined according to the specific shape of the electrode assembly 22. For example, if the electrode assembly 22 is a cylindrical structure, a cylindrical shell can be selected; if the electrode assembly 22 is a cuboid structure, a cuboid shell can be selected. Of course, the end cap 23 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 21 is a rectangular parallelepiped structure, the end cover 23 is a plate-shaped structure, and the end cover 23 covers the opening 211 of the shell 21 .

[0077] 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 23. The positive electrode terminal 24 and the negative electrode terminal 25 are both used to be electrically connected to the electrode assembly 22. 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.

[0078] 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.

[0079] 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 21 and two end caps 23. The shell 21 is a hollow structure with two opposite ends open. One end cap 23 is correspondingly covered at an opening 211 of the shell 21 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 22 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 23 or on different end caps 23; the pressure relief mechanism 26 can be installed on one end cap 23 or on both end caps 23.

[0080] It should be noted that, in the embodiment of the present application, the electrode assembly 22 contained in the housing 21 may be one or more. Figure 3 In the embodiment, there are two electrode assemblies 22, and the two electrode assemblies 22 are stacked.

[0081] The electrode assembly 22 is a component in the battery cell 20 where an electrochemical reaction occurs. The electrode assembly 22 may include a positive electrode sheet, a negative electrode sheet, and a separator. The electrode assembly 22 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.

[0082] According to some embodiments of the present application, referring to Figure 3 , and please refer to Figure 4 , Figure 4 A cross-sectional view of a shell 21 provided in some embodiments of the present application. The present application provides a shell 21, which includes a shell body 212 and an insulating member 213. An opening 211 is formed at one end of the shell body 212 in a preset direction X, and the shell body 212 is used to accommodate the electrode assembly 22. The insulating member 213 is coated on the outside of the shell body 212 and thermally compounded on the outer surface of the shell body 212.

[0083] Among them, the insulating member 213 is thermally composited with the outer surface of the shell body 212, that is, the insulating member 213 is combined with the shell body 212 after hot melting, so that the insulating member 213 is hot-melted and bonded to the outer surface of the shell body 212, thereby eliminating the need to set an adhesive material between the insulating member 213 and the shell body 212 for bonding the two.

[0084] Optionally, the insulating member 213 is a film structure of an organic polymer insulating material, and the insulating member 213 is coated on the outer side of the shell body 212 to achieve insulation isolation between the shell body 212 and the external environment, thereby facilitating the use safety of the battery cell 20 having such a shell 21. In addition, the insulating member 213 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 insulating member 213 can be polypropylene or polyethylene terephthalate.

[0085] By thermally bonding the insulating part 213 to the outer surface of the shell body 212, the bonding strength and structural strength between the insulating part 213 and the shell body 212 can be improved. On the one hand, the shell 21 with such a structure can effectively improve the problem of failure of the bonding force between the insulating part 213 and the shell body 212 during long-term use, thereby helping to reduce the risk of the insulating part 213 falling off or generating a gap between the shell body 212, so as to improve the reliability of the battery cell 20 with such a shell 21. On the other hand, the insulating part 213 can seal and protect the shell body 212, reducing the risk of corrosion or leakage of the shell 21 due to the influence of the external environment, so that the shell 21 has good anti-corrosion and anti-leakage functions, which is beneficial to improve the service life of the battery cell 20 with such a shell 21. In addition, during the production process of the battery cell 20, the process of bonding the blue film to the outer surface of the shell 21 during the assembly of the battery cell 20 is eliminated, and the insulating part 213 can be thermally composited to the outer surface of the shell body 212 in the production branch line of the shell 21 to complete the covering process of the insulating part 213, so that the shell 21 can be produced in parallel with the battery cell 20. That is to say, when the shell 21 enters the production assembly line of the battery cell 20, the covering process of the insulating part 213 has been completed, so that the covering process of the insulating part 213 will not occupy the production rhythm of the battery cell 20, which is beneficial to improve the production efficiency of the battery cell 20.

[0086] According to some embodiments of the present application, see Figure 4 , and please refer to Figure 5 , Figure 5 for Figure 4 The enlarged view of the part of the housing 21 at A is shown. Along the preset direction X, the distance between the edge of the insulating member 213 close to the opening 211 and the opening 211 is 2-6 mm.

[0087] In the preset direction X, the distance between the edge of the insulating member 213 close to the opening 211 and the opening 211 is 2-6 mm, that is, the edge of the insulating member 213 close to the opening 211 and the opening 211 are spaced apart. Figure 5 It can be seen that Figure 5 d in the figure is the distance between the edge of the insulating member 213 close to the opening 211 and the opening 211 in the preset direction X, and the size of d is 2-6 mm.

[0088] By setting a distance between the edge of the insulating member 213 close to the opening 211 in the preset direction X and the opening 211, the influence and interference of the insulating member 213 on the end cover 23 of the battery cell 20 having such a shell 21 when it is covered at the opening 211 of the shell body 212 and connected to the shell body 212 can be reduced, which is beneficial to ensuring the connection reliability between the end cover 23 and the shell 21.

[0089] According to some embodiments of the present application, the thickness of the insulating member 213 is 0.05-0.3 mm.

[0090] By setting the thickness of the insulating part 213 between 0.05 mm and 0.3 mm, on the one hand, the problem of poor insulation and protection effects of the insulating part 213 on the shell body 212 caused by the insulating part 213 being too thin can be reduced, and the service life and reliability of the insulating part 213 can be improved. On the other hand, the problem of excessive space occupied by the shell 21 due to the insulating part 213 being too thick can be alleviated.

[0091] According to some embodiments of the present application, see Figure 4 , and please refer to Figure 6 and Figure 7 , Figure 6 for Figure 4 The enlarged partial view of the B portion of the housing 21 shown, Figure 7 for Figure 4 The enlarged partial view of the C portion of the shell 21 is shown. The insulating member 213 has a plurality of pores that allow at least part of the gas to pass through and prevent the electrolyte from passing through. The shell body 212 is provided with a vent hole 2121 for at least part of the gas to pass through.

[0092] Among them, the insulating member 213 has multiple 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 insulating member 213 is formed with multiple pores, and the pores can allow part of the gas generated inside the shell 21 of the battery cell 20 to pass through, but can prevent the electrolyte in the shell 21 of the battery cell 20 from passing through, so that the insulating member 213 has selective permeability.

[0093] In some embodiments, Figure 4 As shown, the shell body 212 includes a bottom wall 2122 and a side wall 2123, the side wall 2123 is arranged around the bottom wall 2122, one end of the side wall 2123 in the preset direction X is connected to the bottom wall 2122, and the other end of the side wall 2123 in the preset direction X forms an opening 211, and the side wall 2123 and the bottom wall 2122 jointly define a receiving space 2124 for receiving the electrode assembly 22. The bottom wall 2122 and the side wall 2123 are both provided with ventilation holes 2121 (such as Figure 6 and Figure 7 As shown in FIG. 1 , the housing 21 with such a structure is conducive to improving the ventilation efficiency of the battery cell 20 during the later use process, so as to reduce the expansion and contraction of the battery cell 20 during the use process. Of course, in other embodiments, the housing body 212 can also be other structures, for example, only the vent hole 2121 for ventilation is opened on the bottom wall 2122 of the housing body 212, or only the vent hole 2121 for ventilation is opened on the side wall 2123 of the housing body 212.

[0094] For example, in Figure 6 and Figure 7 In the embodiment, a vent hole 2121 is respectively provided on the bottom wall 2122 and the side wall 2123. Of course, in other embodiments, the shell body 212 can also be other structures, for example, the vent holes 2121 provided on the bottom wall 2122 and the side wall 2123 can be two, three, four or five, etc.

[0095] The insulating member 213 has a plurality of pores, which can allow a portion of gas to pass through and can prevent the electrolyte from passing through. Thus, by opening a ventilation hole 2121 on the shell body 212, a portion of the gas in the shell body 212 can pass through the ventilation hole 2121 and then pass through the insulating member 213 to be discharged to the outside of the shell body 212, thereby alleviating the expansion or bloating phenomenon of the battery cell 20 having such a shell 21, which is beneficial to improving the safety and service life of the battery cell 20.

[0096] According to some embodiments of the present application, the pore size is 0.4-189 nm.

[0097] During the use of the battery cell 20, the gases generated in the shell 21 of the battery cell 20 are mainly 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 insulating member 213 can allow these gases to pass through. Among them, the molecular diameter of the electrolyte in the shell 21 of the battery cell 20 is less than 189nm, so that liquid water and solvents cannot pass through the insulating member 213.

[0098] By setting the pore diameter to between 0.4 nm and 189 nm, the pore diameter is larger than the diameter of some gas molecules and smaller than the diameter of liquid molecules of the electrolyte, thereby achieving the function of the insulating member 213 allowing some gas to pass through and preventing the electrolyte from passing through.

[0099] According to some embodiments of this application, see Figure 4The shell body 212 includes a bottom wall 2122 and a side wall 2123. The side wall 2123 is arranged around the bottom wall 2122. One end of the side wall 2123 in the preset direction X is connected to the bottom wall 2122. The other end of the side wall 2123 in the preset direction X forms an opening 211. The side wall 2123 and the bottom wall 2122 jointly define a receiving space 2124 for receiving the electrode assembly 22. The insulating member 213 includes a first insulator 2131 and a second insulator 2132. The first insulator 2131 is arranged on the outer side of the bottom wall 2122, and the second insulator 2132 is arranged on the outer side of the side wall 2123 along the circumference of the side wall 2123. The first insulator 2131 is thermally compounded on the outer surface of the bottom wall 2122. And / or, the second insulator 2132 is thermally compounded on the outer surface of the side wall 2123.

[0100] Among them, the insulating part 213 has a first insulator 2131 and a second insulator 2132. The first insulator 2131 is arranged on the outer side of the bottom wall 2122, so that the first insulator 2131 can insulate and isolate the outer surface of the bottom wall 2122 from the external environment. The second insulator 2132 is arranged on the outer side of the side wall 2123 along the axis of the side wall 2123, that is, the second insulator 2132 is covered on the outer peripheral side of the side wall 2123 along the circumference of the side wall 2123, so that the second insulator 2132 can insulate and isolate the outer surface of the side wall 2123 from the external environment.

[0101] Optionally, the first insulator 2131 is thermally bonded to the outer surface of the bottom wall 2122, and / or the second insulator 2132 is thermally bonded to the outer surface of the side wall 2123. That is, only the first insulator 2131 may be thermally bonded to the outer surface of the bottom wall 2122, or only the second insulator 2132 may be thermally bonded to the outer surface of the side wall 2123, or the first insulator 2131 may be thermally bonded to the outer surface of the bottom wall 2122, and the second insulator 2132 may be thermally bonded to the outer surface of the side wall 2123. Exemplarily, in this embodiment, the first insulator 2131 is thermally bonded to the outer surface of the bottom wall 2122, and the second insulator 2132 is thermally bonded to the outer surface of the side wall 2123.

[0102] The shell body 212 has a bottom wall 2122 and a side wall 2123. The side wall 2123 is surrounded on one side of the bottom wall 2122 so that the side wall 2123 and the bottom wall 2122 together define a receiving space 2124 for receiving the electrode assembly 22. The structure is simple and easy to implement. In addition, by setting the insulating member 213 as two parts, a first insulator 2131 and a second insulator 2132, the first insulator 2131 is used to thermally bond to the outer surface of the bottom wall 2122, and the second insulator 2132 is used to thermally bond to the outer surface of the side wall 2123 along the circumference of the side wall 2123, so that the insulating member 213 is covered on the outer side of the shell body 212. The shell 21 with such a structure is easy to manufacture, which is conducive to reducing the difficulty of processing the shell 21.

[0103] According to some embodiments of the present application, referring to Figure 8 and Fig. 9 , Figure 8 A cross-sectional view of a housing 21 provided in some embodiments of the present application, Fig. 9 for Figure 8 The enlarged partial view of the D portion of the housing 21 is shown. The second insulator 2132 overlaps and is thermally composited at both ends of the side wall 2123 in the circumferential direction to form an overlapping region 2132a.

[0104] The second insulator 2132 overlaps and thermally composites the ends of the side wall 2123 in the circumferential direction, that is, after the second insulator 2132 is coated along the circumferential direction of the side wall 2123 and thermally composited on the outer surface of the side wall 2123, the second insulator 2132 has two free ends (the ends of the ...

[0105] Optionally, the second insulator 2132 may be a single film structure, or may be composed of multiple film structures connected to each other. Figure 8 In the embodiment, the second insulator 2132 is a film structure, and the first and last ends of the second insulator 2132 in the circumferential direction of the side wall 2123 overlap each other and are then thermally composited and connected. In other embodiments, the second insulator 2132 may also be composed of multiple film structures, and the multiple film structures are sequentially connected in the circumferential direction of the side wall 2123, overlap each other, and are then thermally composited and connected.

[0106] By arranging the second insulator 2132 on the outer surface of the side wall 2123 along the circumference of the side wall 2123, and overlapping the head and tail ends of the second insulator 2132 on the circumference of the side wall 2123 and then thermally composited and connected, adopting this structure is beneficial to improving the connection strength between the head and tail ends of the second insulator 2132, and can reduce the risk of generating gaps after the second insulator 2132 is thermally composited on the outer surface of the side wall 2123, thereby alleviating the phenomenon that substances in the external environment enter between the second insulator 2132 and the outer surface of the shell body 212 through the gaps in the second insulator 2132 and cause corrosion of the shell body 212, which is beneficial to improving the corrosion resistance of the shell 21.

[0107] According to some embodiments of this application, please continue to refer to Figure 8 and Fig. 9 The side wall 2123 includes two first walls 2123a and two second walls 2123b. One first wall 2123a, one second wall 2123b, another first wall 2123a and another second wall 2123b are connected end to end in sequence, the two first walls 2123a are opposite and spaced apart, the two second walls 2123b are opposite and spaced apart, and the area of ​​the first wall 2123a is greater than the area of ​​the second wall 2123b. The overlapping area 2132a is arranged correspondingly to the second wall 2123b.

[0108] Among them, a first wall 2123a, a second wall 2123b, another first wall 2123a and another second wall 2123b in the side wall 2123 are connected end to end in sequence, that is, the side wall 2123 has two first walls 2123a arranged oppositely and spaced apart and two second walls 2123b arranged oppositely and spaced apart, one end of the first wall 2123a and one end of the second wall 2123b are connected to each other to form a shell 21 structure of a quadrilateral structure. For example, in Figure 8 In the embodiment, the shell body 212 is a rectangular parallelepiped structure, and the area of ​​the first wall 2123a of the side wall 2123 is larger than the area of ​​the second wall 2123b.

[0109] Since the head and tail ends of the second insulator 2132 will protrude from the outer surface of the shell body 212 after overlapping each other, by setting the overlapping area 2132a of the second insulator 2132 on the second wall 2123b with a smaller area in the side wall 2123, this structure can, on the one hand, reduce the risk of cracks in the overlapping area 2132a due to the large deformation of the first wall 2123a with a larger area during the expansion or contraction of the battery cell 20, thereby helping to improve the long-term use reliability of the insulating part 213; on the other hand, when multiple battery cells 20 having such a shell 21 are assembled together, it is helpful to alleviate the risk of increased deformation of the shell 21 of the battery cell 20 due to the influence of the overlapping area 2132a when a collision occurs between the battery cells 20.

[0110] According to some embodiments of the present application, a nano-plating layer is formed on the outer surface of the bottom wall 2122 and the outer surface of the side wall 2123 .

[0111] The outer surface of the bottom wall 2122 and the outer surface of the side wall 2123 are both formed with a nano-coating, that is, the outer surface of the bottom wall 2122 and the outer surface of the side wall 2123 are both nano-processed, so that a nano-coating is formed on the outer surface of the bottom wall 2122 and the outer surface of the side wall 2123. Optionally, the outer surface of the side wall 2123 may be partially formed with a nano-coating, or the entire outer surface of the side wall 2123 may be formed with a nano-coating.

[0112] By forming a nano-plating layer on the outer surface of the bottom wall 2122 and the outer surface of the side wall 2123, and thermally compounding the insulating member 213 on the nano-plating layer, the bonding strength between the insulating member 213 and the outer surface of the shell body 212 can be further improved, so as to reduce the risk of the insulating member 213 falling off or generating a gap, thereby improving the reliability of the shell 21. In addition, after improving the bonding strength between the insulating member 213 and the bottom wall 2122, the phenomenon of the gap between the insulating member 213 and the bottom wall 2122 can be reduced, so that the battery cell 20 having such a shell 21 can transfer heat through the bottom wall 2122, thereby reducing the influence of the gap between the insulating member 213 and the bottom wall 2122 on the heat transfer, thereby facilitating the improvement of the heat dissipation effect of the battery cell 20.

[0113] Furthermore, if Figure 8As shown, the side wall 2123 includes two first walls 2123a and two second walls 2123b. One first wall 2123a, one second wall 2123b, another first wall 2123a and another second wall 2123b are connected end to end in sequence, the two first walls 2123a are opposite and spaced apart, the two second walls 2123b are opposite and spaced apart, and the area of ​​the first wall 2123a is greater than the area of ​​the second wall 2123b. A nano-plating layer is formed on the outer surface of the first wall 2123a.

[0114] The outer surface of the first wall 2123 a is formed with a nano-plating layer, that is, the shell body 212 is a rectangular parallelepiped structure, and the larger side surfaces of the shell body 212 are nano-processed.

[0115] It should be noted that the second wall 2123b of the shell body 212 can also be nano-processed, and the structure of the nano-coating formed on the second wall 2123b can be various. For example, the nano-coating can be formed on the entire outer surface of the second wall 2123b, or the nano-coating can be formed on the outer surface of the second wall 2123b corresponding to the edge of the insulating part 213 near the opening 211 in the preset direction X, so as to improve the bonding strength and stability between the edge of the insulating part 213 near the opening 211 in the preset direction X and the second wall 2123b.

[0116] Since the first wall 2123a with a larger area in the side wall 2123 produces a larger deformation during the expansion or contraction of the battery cell 20, the bonding strength between the second insulator 2132 and the first wall 2123a is improved by forming a nano-coating on the outer surface of the first wall 2123a, which helps to reduce the risk of the second insulator 2132 arranged on the outer surface of the first wall 2123a falling off or creating gaps due to the large deformation of the first wall 2123a.

[0117] According to some embodiments of this application, see Figure 4 As shown, one end of the second insulator 2132 away from the opening 211 in the preset direction X is thermally compositely connected to the first insulator 2131 .

[0118] The end of the second insulator 2132 away from the opening 211 in the preset direction X is thermally compositely connected to the first insulator 2131 , that is, the end of the second insulator 2132 in the preset direction X and the first insulator 2131 are hot-melted and bonded together.

[0119] Optionally, in other embodiments, the first insulator 2131 and the second insulator 2132 may also be an integrated structure.

[0120] By thermally composite-connecting the first insulator 2131 and one end of the second insulator 2132, the insulating member 213 with such a structure can, on the one hand, improve the connection strength between the first insulator 2131 and the second insulator 2132, and on the other hand, reduce the phenomenon of a gap between the first insulator 2131 and the second insulator 2132, thereby helping to reduce the risk of substances from the external environment penetrating through the gap between the first insulator 2131 and the second insulator 2132.

[0121] According to some embodiments of the present application, the material of the insulating member 213 includes polar groups.

[0122] The material of the insulating member 213 has polar groups, that is, after the insulating member 213 is processed, polar groups will be formed in the material of the insulating member 213, and the polar groups can be one or more of -COOH, -OH, -CHO, -NH2 or -SH.

[0123] Exemplarily, when the material of the insulating member 213 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, thereby making the material of the insulating member 213 have polar groups.

[0124] The insulating member 213 is made of a material having polar groups, that is, the insulating member 213 has polar groups therein, and the polar groups can effectively improve the bonding strength between the insulating member 213 and the outer surface of the shell body 212, thereby facilitating further improving the bonding strength between the insulating member 213 and the shell body 212.

[0125] According to some embodiments of the present application, referring to Fig.10 , Fig.10 The present application also provides a battery cell 20, including an electrode assembly 22, an end cap 23 and a shell 21 of any of the above schemes. The electrode assembly 22 is placed in the shell body 212, and the end cap 23 covers the opening 211 of the shell body 212.

[0126] According to some embodiments of the present application, see Fig.10 , and please refer to Fig.11 , Fig.11 for Fig.10 The end cap 23 is welded to one end of the shell body 212 in the preset direction X, and forms a weld mark 28 extending along the circumference of the opening 211. The battery cell 20 also includes a protective member 27, which covers the weld mark 28 along the circumference of the opening 211.

[0127] The end cover 23 is welded to one end of the shell body 212 in the preset direction X, and forms a weld mark 28 extending along the circumference of the opening 211, that is, after the end cover 23 covers the opening 211 of the shell body 212, the end cover 23 needs to be connected to one end of the shell body 212. Since the end cover 23 is connected to one end of the shell body 212 by welding, it is helpful to improve the connection strength between the end cover 23 and the shell body 212, so that a weld mark 28 is formed at the connection between the end cover 23 and the shell body 212, and the weld mark 28 is arranged around the outer peripheral side of the shell body 212 and the end cover 23 along the circumference of the opening 211. In other embodiments, the end cover 23 can also be bonded or clamped to the shell body 212.

[0128] The protective member 27 covers the weld mark 28 along the circumference of the opening 211, that is, the protective member 27 is arranged on the outer side of the shell body 212 along the circumference of the opening 211, and the weld mark 28 is covered in the protective member 27. Exemplarily, the protective member 27 can be bonded to the outer surface of the weld mark 28, or can be thermally compounded to the outer surface of the weld mark 28. In this embodiment, the protective member 27 is bonded to the outer surface of the weld mark 28, for example, the protective member 27 can be an insulating tape or a blue film, and the protective member 27 is bonded to the outer surface of the weld mark 28 by glue.

[0129] By arranging the protective member 27 on the outer side of the shell 21 along the circumference of the opening 211, and covering the protective member 27 on the outer side of the weld mark 28 formed between the end cover 23 and the shell body 212 along the circumference of the opening 211 to separate the weld mark 28 from the external environment, the connection between the end cover 23 and the shell body 212 is insulated and isolated from the external environment, which is beneficial to enhance the protection of the battery cell 20.

[0130] According to some embodiments of this application, please refer to Fig.11 Along the preset direction X, the edge of the insulating member 213 close to the opening 211 is spaced from the weld mark 28. At least a portion of the protective member 27 in the preset direction X is wrapped around the outer side of the insulating member 213 along the circumference of the opening 211.

[0131] Among them, along the preset direction X, there is a distance between the edge of the insulating member 213 close to the opening 211 and the weld mark 28, that is, in the preset direction X, the edge of the insulating member 213 close to the opening 211 is spaced from the weld mark 28, that is, the edge of the insulating member 213 close to the opening 211 is spaced from the connection area between the end cover 23 and the shell body 212. And at least part of the protective member 27 in the preset direction X is coated on the outside of the insulating member 213 along the circumference of the opening 211, that is, one end of the protective member 27 close to the insulating member 213 in the preset direction X covers the insulating member 213 along the circumference of the shell body 212, that is, one end of the protective member 27 close to the insulating member 213 in the preset direction X overlaps the outside of the insulating member 213. Exemplarily, the part of the protective member 27 coated on the outside of the insulating member 213 is bonded to the outer surface of the insulating member 213.

[0132] Since there is a certain distance between the edge of the insulating member 213 near the opening 211 in the preset direction X and the weld mark 28, after the protective member 27 is covered on the weld mark 28 along the circumferential direction of the opening 211, one end of the protective member 27 near the insulating member 213 in the preset direction X overlaps with one end of the insulating member 213 near the opening 211 in the preset direction X, so that the protective member 27 can cover and cover the edge of the insulating member 213 near the opening 211 in the preset direction X. The battery cell 20 adopting such a structure can, on the one hand, reduce the risk of substances from the external environment entering between the insulating member 213 and the outer surface of the shell body 212 through the edge of the insulating member 213, and on the other hand, the protective member 27 can strengthen the bonding strength between the edge of the insulating member 213 near the opening 211 in the preset direction X and the outer surface of the shell body 212, thereby alleviating the risk of the edge of the insulating member 213 falling off or generating a gap due to failure of the bonding force during later use.

[0133] 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 .

[0134] 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.

[0135] The power-consuming device may be any of the aforementioned devices or systems using the battery 100 .

[0136] According to some embodiments of the present application, see Figure 4-Figure 9As shown, the present application provides a shell 21, which includes a shell body 212 and an insulating member 213. The shell body 212 has a bottom wall 2122 and a side wall 2123, and the outer surface of the bottom wall 2122 and the outer surface of the side wall 2123 are both formed with a nano-plating layer, and the side wall 2123 is arranged around the bottom wall 2122, and one end of the side wall 2123 in a preset direction X is connected to the bottom wall 2122, and the other end forms an opening 211, and the side wall 2123 and the bottom wall 2122 jointly define a receiving space 2124 for receiving the electrode assembly 22, and the side wall 2123 is a rectangular hollow structure, and the side wall 2123 has two first walls 2123a and two second walls 2123b arranged opposite to each other, and the area of ​​the first wall 2123a is larger than that of the second wall 2123b. The insulating member 213 has a first insulator 2131 and a second insulator 2132 which are thermally composited and connected to each other. The first insulator 2131 is thermally composited to the outer surface of the bottom wall 2122, and the second insulator 2132 is thermally composited to the outer surface of the side wall 2123 along the circumference of the side wall 2123. The second insulator 2132 overlaps with each other at both ends in the circumference of the side wall 2123 and then thermally composited, and the formed overlapping area 2132a is correspondingly arranged on the second wall 2123b. Among them, polar groups are formed in the material of the insulating member 213, and the insulating member 213 has a plurality of pores with a pore size of 0.4-189nm. Correspondingly, the bottom wall 2122 and the side wall 2123 of the shell body 212 are both provided with ventilation holes 2121 for ventilation.

[0137] According to some embodiments of the present application, see Figure 10-11 As shown, the present application provides a battery cell 20, which includes an electrode assembly 22, an end cap 23, a protective member 27 and the above-mentioned shell 21, wherein the electrode assembly 22 is placed in the shell 21, and the insulating member 213 of the shell 21 is spaced from the opening 211 near the edge of the opening 211 in the preset direction X, with a distance of 2-6 mm. After the end cap 23 is covered on the opening 211, it is welded to one end of the shell 21 to form a weld mark 28 extending along the circumference of the opening 211 and located on the outside of the shell body 212, and the weld mark 28 is spaced from the edge of the insulating member 213 in the preset direction X. The protective member 27 is coated on the outer surface of the weld mark 28 along the circumference of the opening 211, and one end of the protective member 27 in the preset direction X is coated on the outside of the insulating member 213 along the circumference of the opening 211.

[0138] 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.

[0139] 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: A shell body, wherein an opening is formed at one end of the shell body in a preset direction, and the shell body is used to accommodate the electrode assembly; as well as An insulating member, the insulating member is coated on the outer side of the shell body and thermally bonded to the outer surface of the shell body; The shell body includes a bottom wall and a side wall, the side wall is arranged around the bottom wall, one end of the side wall in the preset direction is connected to the bottom wall, the other end of the side wall in the preset direction forms the opening, the side wall and the bottom wall together define a receiving space for receiving the electrode assembly, the insulating member includes a first insulator and a second insulator, the first insulator is arranged on the outside of the bottom wall, the second insulator is arranged on the outside of the side wall along the circumference of the side wall, and the first insulator is thermally compounded with the outer surface of the bottom wall; and / or, the second insulator is thermally composited to the outer surface of the side wall; The second insulator overlaps and thermally composites the end portions of the side wall in the circumferential direction to form an overlapping area. The side wall includes two first walls and two second walls. One first wall, one second wall, another first wall and another second wall are connected end to end in sequence. The two first walls are arranged opposite to each other and spaced apart, and the two second walls are arranged opposite to each other and spaced apart. The area of ​​the first wall is greater than that of the second wall, and the overlapping area is arranged corresponding to the second wall.

2. The housing according to claim 1, characterized in that Along the preset direction, the distance between the edge of the insulating member close to the opening and the opening is 2-6 mm.

3. The housing according to claim 1, characterized in that The thickness of the insulating member is 0.05-0.3 mm.

4. The housing according to claim 1, characterized in that The insulating member has a plurality of pores that allow at least part of the gas to pass through and prevent the electrolyte from passing through; The shell body is provided with a vent hole for allowing at least part of the gas to pass through.

5. The housing according to claim 4, characterized in that: The pores have a pore diameter of 0.4-189 nm.

6. The housing according to claim 1, characterized in that The outer surface of the bottom wall and the outer surface of the side wall are both formed with a nano-plating layer.

7. The housing according to claim 6, characterized in that The side wall includes two first walls and two second walls; One first wall, one second wall, another first wall and another second wall are connected end to end in sequence, two first walls are arranged opposite to each other and spaced apart, two second walls are arranged opposite to each other and spaced apart, and an area of ​​the first wall is greater than an area of ​​the second wall; Wherein, the nano-plating layer is formed on the outer surface of the first wall.

8. The housing according to claim 1, characterized in that One end of the second insulator away from the opening in the preset direction is thermally compositely connected to the first insulator.

9. The housing according to any one of claims 1 to 5, characterized in that: The material of the insulating member includes polar groups.

10. A battery cell, characterized in that: include: The housing according to any one of claims 1 to 9; An electrode assembly, wherein the electrode assembly is placed in the shell body; as well as An end cover is provided to cover the opening of the shell body.

11. The battery cell according to claim 10, characterized in that: The end cover is welded to one end of the shell body in the preset direction, and forms a weld mark extending along the circumference of the opening; The battery cell further includes a protection member, and the protection member covers the weld mark along a circumference of the opening.

12. The battery cell according to claim 11, characterized in that: Along the preset direction, the edge of the insulating member close to the opening is spaced apart from the weld mark; At least a portion of the protection member in the preset direction is covered on the outer side of the insulating member along the circumference of the opening.

13. A battery, characterized in that: include: A battery cell as claimed in any one of claims 10 to 12; as well as A box body is used to accommodate the battery cells.

14. An electrical device, characterized in that: Comprising a battery as claimed in claim 13, the battery is used to provide electrical energy.

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