Battery monomer, battery device and electric device

Abstract

The embodiment of the utility model provides a battery monomer, a battery device and a power utilization device, and relates to the technical field of batteries. The battery monomer comprises a shell, an electrode assembly, an insulating part and electrolyte. Wherein the insulating part is integrally formed through injection molding and comprises a first side wall and a first bottom wall, the first side wall is arranged on the periphery of the first bottom wall, the first side wall and the first bottom wall jointly define a containing cavity with an opening, the opening and the first bottom wall are oppositely arranged, and at least part of the electrode assembly and at least part of the electrolyte are contained in the containing cavity; the inner circumferential surface of the first side wall is a continuous surface. The insulating part is integrally formed by injection molding, and the inner circumferential surface of the formed first side wall is a continuous surface, so that an electrolyte positioned on the inner side of the insulating part is difficult to flow out from the side wall of the insulating part in the normal use process of the battery monomer, the electrolyte can be positioned on the inner side of the insulating part for a longer time, and an infiltration effect can be more effectively formed on the electrode assembly; and the purpose of improving the electrolyte utilization rate is achieved.

Description

Technical Field

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

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

[0003] In the development of battery technology, battery reliability is an issue that cannot be ignored. If the reliability of the battery cannot be guaranteed, the battery cannot be used. Therefore, how to enhance the reliability of the battery is a technical problem that needs to be solved urgently in battery technology. Utility Model Content

[0004] The present application provides a battery cell, a battery device and an electrical device, which can improve the reliability of the battery.

[0005] This application is achieved through the following technical solutions:

[0006] In a first aspect, an embodiment of the present application provides a battery cell, comprising a housing, an electrode assembly, an insulating member, and an electrolyte. The insulating member is integrally formed, and comprises a first side wall and a first bottom wall, the first side wall is disposed around the first bottom wall, and together with the first bottom wall, forms a receiving cavity having an opening, the opening is disposed opposite to the first bottom wall, at least a portion of the electrode assembly and at least a portion of the electrolyte are received in the receiving cavity, and the inner circumference of the first side wall is a continuous surface.

[0007] In the above embodiment, the insulating part is integrally formed, and the inner peripheral surface of the first side wall is a continuous surface after forming. During normal use of the battery cell, the electrolyte located on the inner side of the insulating part is difficult to flow out from the side wall of the insulating part. On the one hand, the electrolyte can be located on the inner side of the insulating part for a longer time, which can more effectively form an infiltration effect on the electrode assembly, thereby achieving the purpose of improving the utilization rate of the electrolyte. On the other hand, the carbon powder shed from the negative electrode of the electrode assembly is also difficult to contact the outer shell, which reduces the risk of corrosion to the outer shell, can improve the reliability of the battery cell, and can also increase the service life of the battery cell. At the same time, the insulating part is integrally formed, which reduces the original folding and hot-melt processes during assembly and improves assembly efficiency.

[0008] In some embodiments, the insulating member is integrally injection molded. In other embodiments, the insulating member may also be integrally blow molded or integrally compression molded.

[0009] In some embodiments, the first bottom wall is provided with a first through hole. By providing the first through hole in the first bottom wall, the electrolyte flowing to the bottom of the housing can flow back to the inside of the insulating member through the first through hole, continue to infiltrate the electrode assembly, and realize the reuse of the electrolyte. The provision of the first through hole can ensure that a certain amount of electrolyte can always exist inside the insulating member, thereby having a good infiltration effect on the electrode assembly.

[0010] In some embodiments, the battery cell further includes a filter membrane, which is connected to the side of the first bottom wall away from the accommodating cavity and covers the first through hole. By providing the filter membrane covering the first through hole, the speed at which the electrolyte flows from the inside of the insulating member to the outside thereof can be slowed down, so that the electrolyte can be located inside the insulating member for a longer time, thereby achieving a better effect of wetting the electrode assembly.

[0011] In some embodiments, the housing may include a shell and an end cap. The shell includes a second side wall and a second bottom wall, the second side wall is arranged around the second bottom wall, one end of the second side wall is connected to the second bottom wall, and the other end of the second side wall is connected to the end cap. The filter membrane is in direct contact with the second bottom wall. The filter membrane is connected to the side of the first bottom wall away from the accommodating cavity and is in direct contact with the second bottom wall. It is possible to reduce the gap between the insulating member and the bottom wall of the housing, thereby reducing the ineffective enrichment area of ​​the electrolyte, thereby improving the wetting effect of the electrolyte on the electrode assembly, and achieving the purpose of improving the utilization rate of the electrolyte.

[0012] In some embodiments, the housing further comprises an arc transition portion, and the second side wall and the second bottom wall are connected via the arc transition portion. The thickness direction of the first bottom wall is a first direction, and along the first direction, the thickness of the filter membrane is d 1 , the size of the arc transition part is d 2 , d 1 ≥d 2 In this embodiment, the thickness of the filter membrane is set to be greater than or equal to the size of the arc transition portion in the first direction, so that the insulating member can avoid the arc transition portion in the shell, reduce the interference of the arc transition portion, and thus make it easier to assemble the insulating member with the shell, thereby improving the assembly efficiency of the battery cell.

[0013] In some embodiments, the thickness of the filter membrane is 0.5 mm to 3 mm. The thickness of the filter membrane is selected to be a specific size within this size range, which can achieve good results.

[0014] In some embodiments, the thickness direction of the first bottom wall is still taken as the first direction, and the projection area of ​​the filter membrane on the projection plane perpendicular to the first direction is S 1 , the projected area of ​​the electrode assembly is S 2 , S 1 ≥80%*S 2The electrode assembly and the insulating member form a whole. When the electrode assembly and the outer shell are assembled, the closer the projection area of ​​the filter membrane is to the projection area of ​​the electrode assembly, the smaller the gap between the second bottom wall and the first bottom wall, the less electrolyte can be enriched in the gap, and the electrolyte can flow more inside the insulating member, which can have a better infiltration effect on the electrode assembly and a higher utilization rate of the electrolyte.

[0015] In some embodiments, the filter membrane includes a first side surface and a second side surface, the first side surface faces the insulating member, and the second side surface faces away from the insulating member. The filter membrane may be a one-way membrane, which allows the electrolyte to flow from the side where the second side surface is located to the side where the first side surface is located. In the above embodiments, the filter membrane is a one-way membrane. When the battery cell is placed and used normally, it is difficult for the electrolyte to flow from the inside of the insulating member to the outside thereof; when the electrolyte flows to the inside of the shell, it can flow to the inside of the insulating member through the one-way membrane and continue to infiltrate the electrode assembly.

[0016] In some embodiments, the filter membrane may be made of polytetrafluoroethylene (PTFE), polyolefin (PO) or nylon 66 (N66). When using the material, the filter membrane can form a one-way membrane suitable for battery cells to achieve the purpose of improving the utilization rate of the electrolyte.

[0017] In some embodiments, the filter membrane is connected to the first bottom wall by heat melting or bonding. The connection between the filter membrane and the first bottom wall can be achieved by any of the methods in the above embodiments.

[0018] In some embodiments, the first side wall includes two first sub-side walls arranged opposite to each other along the second direction and two second sub-side walls arranged opposite to each other along the third direction. The thickness direction of the first bottom wall is still taken as the first direction, wherein the first direction, the second direction and the third direction are perpendicular to each other. A groove is formed on the inner surface of the second sub-side wall. The electrode assembly includes a bending area, and at least a portion of the bending area is located in the groove. In the above embodiments, a groove is formed on the inner surface of the second sub-side wall, and the bending area of ​​the electrode assembly is at least partially located in the groove, and the insulating member can better cover the electrode assembly.

[0019] In some embodiments, the outer surface area of ​​the first sub-sidewall is larger than the outer surface area of ​​the second sub-sidewall. The groove is provided on the second sub-sidewall with a relatively smaller outer surface area to match and assemble a conventionally used electrode assembly.

[0020] In some embodiments, a plurality of electrode assemblies are provided, and the plurality of electrode assemblies are arranged along the second direction. The insulating member accommodates the plurality of electrode assemblies, and in the region of each accommodated electrode assembly, a plurality of grooves are formed on the inner surface of each second sub-side wall, and the grooves correspond one to one with the electrode assemblies. In this embodiment, a plurality of grooves are formed on the inner surface of the second sub-side walls arranged opposite to each other, and two opposite grooves correspond to one electrode assembly, and the bending areas of the edges on the opposite sides of the electrode assembly are at least partially located in the corresponding grooves. By providing a plurality of electrode assemblies, different battery cells are formed to meet the needs of different usage scenarios.

[0021] In some embodiments, a second through hole is provided on the second sub-side wall, and two adjacent grooves are connected through the second through hole. The second through hole can allow the electrolyte to infiltrate each other between the multiple electrode assemblies, which can effectively improve the utilization rate of the electrolyte.

[0022] In some embodiments, along the first direction, the second sub-side wall has a first edge away from the first bottom wall, and the distance between the second through hole and the first edge is greater than the distance between the second through hole and the first bottom wall. In this embodiment, the second through hole is arranged in the middle and lower region of the second sub-side wall, and when there is less electrolyte, the second through hole can also well support the electrolyte to flow between adjacent electrode assemblies, thereby achieving mutual infiltration between multiple electrode assemblies.

[0023] In some embodiments, the first side wall includes two first sub-side walls arranged opposite to each other along the second direction and two second sub-side walls arranged opposite to each other along the third direction; the thickness direction of the first bottom wall is the first direction, and the first direction, the second direction and the third direction are perpendicular to each other; a first guide surface is provided at one end of the first sub-side wall away from the first bottom wall, and the first guide surface is connected to the inner surface of the first sub-side wall; and / or a second guide surface is provided at one end of the second sub-side wall away from the first bottom wall, and the second guide surface is connected to the inner surface of the second sub-side wall. During the assembly process of the electrode assembly and the insulating member, the first guide surface and / or the second guide surface can guide the insulating member to be gradually accommodated in the insulating member, which can effectively improve the assembly of the two.

[0024] In some embodiments, the minimum thickness of the first side wall is 0.1 mm to 0.5 mm; the minimum thickness of the first bottom wall is 0.1 mm to 0.5 mm. By selecting a size within this size range, the purpose of use requirements can be met and the overall economy of the battery cell can be improved.

[0025] In some of the embodiments, the insulating member may be made of polypropylene or polyethylene.

[0026] In a second aspect, an embodiment of the present application provides a battery device, comprising a battery cell according to any one of the above embodiments.

[0027] In a third aspect, an embodiment of the present application provides an electrical device, comprising the battery device of any one of the above embodiments.

[0028] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] 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.

[0030] Figure 1 A schematic diagram of the structure of a vehicle according to some embodiments of the present application;

[0031] Figure 2 A schematic diagram of the exploded structure of a battery device according to some embodiments of the present application;

[0032] Figure 3 A schematic diagram of the exploded structure of a battery cell according to some embodiments of the present application;

[0033] Figure 4 A schematic diagram of the structure of a battery cell in some embodiments of the present application;

[0034] Figure 5 This is a schematic diagram of the structure of the insulating member in some embodiments of the present application;

[0035] Figure 6 A perspective view of an insulating member in some embodiments of the present application;

[0036] Figure 7 This is a schematic diagram of the separate structure of the insulating member and the filter membrane in some embodiments of the present application;

[0037] Figure 8 A schematic diagram of the cross-sectional structure of a battery cell in some embodiments of the present application;

[0038] Fig. 9 A top view of a battery cell in some embodiments of the present application;

[0039] Fig.10 for Fig. 9 AA section view;

[0040] Fig.11 for Fig.10 A local enlarged view at C;

[0041] Fig.12 for Fig. 9 BB cross-sectional view;

[0042] Fig.13 for Fig.12 A local enlarged view at D;

[0043] icon:

[0044] 1000, vehicle; 100, battery device; 200, controller; 300, motor; 10, housing; 11, first sub-housing; 12, second sub-housing; 20, battery cell; 201, housing; 2011, shell; 20111, second side wall; 20112, second bottom wall; 20113, arc transition portion; 2012, end cap; 202, electrode assembly; 2021, bending area; 203, insulating member; 2031, first side wall; 20311, first sub-side wall; 203111, first guide surface; 20312, second sub-side wall; 203121, groove; 203122, second through hole; 203123, second guide surface; 203124, first edge; 2032, first bottom wall; 20321, first through hole; 204, filter membrane;

[0045] X is the first direction; Y is the second direction; Z is the third direction. DETAILED DESCRIPTION

[0046] 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 and completely 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.

[0047] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning 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.

[0048] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations 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. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0049] 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.

[0050] The term "multiple" as used in the present application refers to more than two (including two). Similarly, the term "multiple groups" refers to more than two groups (including two groups), and the term "multiple sheets" refers to more than two sheets (including two sheets).

[0051] The battery device mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include a plurality of battery cells, and the plurality of battery cells are connected in series, in parallel or in hybrid connection through a busbar.

[0052] In some embodiments, the battery cell assembly is generally formed by arranging a plurality of battery cells; as an example, the battery cell assembly may be a battery module, which is formed by arranging and fixing a plurality of battery cells to form an independent module. As an example, the battery module may be formed by bundling a plurality of battery cells by a cable tie.

[0053] In some embodiments, the battery device may be a battery pack, which includes a case and one or more battery cell assemblies, wherein the battery cell assemblies are accommodated in the case.

[0054] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0055] As an example, the battery cell assembly may also be housed in the case by directly fixing a plurality of battery cells to the case.

[0056] As an example, the box may include a first sub-box and a second sub-box. The first sub-box and the second sub-box are buckled together to form a closed space inside the box to accommodate the battery cell assembly. The closed here means covered or closed, which can be sealed or unsealed. The first sub-box can be a top cover or a bottom plate.

[0057] As an example, the box body may include a top cover, a frame and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that a closed space is formed inside the box body to accommodate the battery cell assembly.

[0058] As an example, the box body can be used as a part of the chassis structure of the vehicle. For example, the top cover of the box body can become at least a part of the bottom plate of the vehicle, or the frame of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0059] In some embodiments, the battery device refers to an energy storage device, which includes a box body, at least one side of which is provided with a door. The energy storage device includes an energy storage container, an energy storage cabinet, and the like.

[0060] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0061] The battery cells may be, but are not limited to, lithium ion batteries, sodium ion batteries, sodium lithium ion batteries, lithium metal batteries, sodium metal batteries, lithium sulfur batteries, magnesium ion batteries, nickel hydrogen batteries, nickel cadmium batteries, lead storage batteries, etc.

[0062] A battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are embedded and removed between the positive electrode and the negative electrode. The separator is set between the positive electrode and the negative electrode to reduce the short circuit between the positive and negative electrodes, while allowing the active ions to pass through.

[0063] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0064] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0065] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, stainless steel, copper, aluminum, nickel, carbon electrode, carbon or titanium with a silver-plated surface may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0066] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for batteries may also be used.

[0067] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0068] As an example, the negative electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, copper, aluminum, nickel, carbon electrode, carbon or titanium, etc. may be used.

[0069] In some embodiments, the negative electrode current collector has two surfaces opposite to each other in its thickness direction, and the negative electrode active material is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.

[0070] As an example, the negative electrode active material may adopt the negative electrode active material for the battery known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials and lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0071] In some embodiments, the separator is a separator. The present application has no particular limitation on the type of separator, and any known separator with a porous structure having good chemical reliability and mechanical reliability can be selected.

[0072] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without special restrictions. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without special restrictions. The separator can be a separate component located between the positive and negative electrodes, or it can be attached to the surface of the positive and negative electrodes.

[0073] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transmit ions and isolate the positive and negative electrodes.

[0074] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into the wound structure.

[0075] In some embodiments, the electrode assembly is a laminate structure.

[0076] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing may be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film.

[0077] In some embodiments, the housing includes an end cap and a shell, the shell is provided with an opening, and the end cap closes the opening to form a closed space for accommodating substances such as the electrode assembly and the electrolyte. The shell may be provided with one or more openings. One or more end caps may also be provided.

[0078] In some embodiments, at least one electrode terminal is disposed on the housing, and the electrode terminal is electrically connected to the electrode tab of the electrode assembly. The electrode terminal may be directly connected to the electrode tab, or may be indirectly connected to the electrode tab through an adapter. The electrode terminal may be disposed on the end cap, or may be disposed on the housing.

[0079] In some embodiments, an explosion-proof valve is provided on the housing, and the explosion-proof valve is used to release the internal pressure of the battery cell.

[0080] In some embodiments, the housing may be a sealed structure or a non-sealed structure. As an example, when the housing is a sealed structure, the housing may protect the electrode assembly and reduce leakage of electrolyte. When the housing is a non-sealed structure, the housing may protect the electrode assembly, and a sealing bag may be included between the housing and the electrode assembly, the sealing bag being used to encapsulate the electrode assembly and the electrolyte. Specifically, the sealing bag may be a bag-shaped insulating member or an aluminum-plastic film.

[0081] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, a polygonal prismatic battery, such as a hexagonal prismatic battery, etc. There is no particular limitation in the embodiments of the present application.

[0082] During the preparation of battery cells, before the electrode assembly is placed in the housing, it is necessary to use an insulating member to cover the electrode assembly to reduce the risk of short circuit between the electrode assembly and the housing. Currently, the insulating member is usually a plurality of substrates before assembly. When in use, the plurality of substrates need to be folded to form a cavity structure with one side open, and then the connecting edges of adjacent substrates are connected by a hot melt process. However, during the hot melt process, it is difficult to completely close the connecting edges of adjacent substrates due to the process itself, resulting in gaps in the connecting areas of adjacent substrates. In the subsequent assembly process, electrolyte needs to be added to the insulating part to wet the electrode assembly. The gap formed in the connection area of ​​adjacent substrates will cause the added electrolyte to flow to the outside of the insulating part. On the one hand, this will reduce the electrolyte that can effectively wet the electrode assembly, resulting in a decrease in the utilization rate of the electrolyte. On the other hand, the carbon powder of the negative electrode of the electrode assembly may fall off. In the process of the electrolyte flowing from the inside to the outside of the insulating part, the detached carbon powder will follow the electrolyte to the outside of the insulating part, contact and react with the outer shell, causing corrosion of the outer shell, thereby affecting the reliability of the battery cell.

[0083] The embodiments of the present application provide a battery cell, a battery device, and an electrical device, wherein the first side wall of the insulating member is formed integrally, and the inner circumference of the first side wall can form a continuous surface, so as to reduce the flow of electrolyte to the outside of the insulating member. Based on the above configuration, on the one hand, the utilization rate of the electrolyte can be improved, and on the other hand, the risk of reduced reliability caused by the contact between the carbon powder of the negative electrode of the electrode assembly and the outer shell can be reduced.

[0084] The battery device disclosed in the embodiment of the present application can be used in, but not limited to, electrical equipment such as vehicles, ships or aircraft. The battery device disclosed in the present application can be used to form a power supply system of the electrical equipment.

[0085] The technical solutions described in the embodiments of the present application are applicable to various electrical devices that use battery cells and battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, for example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.

[0086] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device in an embodiment of the present application.

[0087] Please refer to Figure 1 , Figure 1A 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 device 100 is provided inside the vehicle 1000, and the battery device 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery device 100 may be used for powering the vehicle 1000. For example, the battery device 100 may be used as an operating power source for the vehicle 1000, for the circuit system of the vehicle 1000, for example, for the working power requirements during the startup, navigation and operation of the vehicle 1000.

[0088] The vehicle 1000 may further include a controller 200 and a motor 300 , wherein the controller 200 is used to control the battery device 100 to supply power to the motor 300 , for example, to meet the power requirements of starting, navigating, and driving the vehicle 1000 .

[0089] In some embodiments of the present application, the battery device 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.

[0090] Please refer to Figure 2 , Figure 2 A schematic diagram of the structure of a battery device 100 provided in some embodiments of the present application. The battery device 100 includes a box 10 and a battery cell 20, and the battery cell 20 is contained in the box 10. Among them, the box 10 is used to provide a storage 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 sub-box 11 and a second sub-box 12, and the first sub-box 11 and the second sub-box 12 cover each other, and the first sub-box 11 and the second sub-box 12 jointly define a storage space for accommodating the battery cell 20. The second sub-box 12 can be a hollow structure with one end open, and the first sub-box 11 can be a plate-like structure. The first sub-box 11 covers the open side of the second sub-box 12, so that the first sub-box 11 and the second sub-box 12 jointly define a storage space; the first sub-box 11 and the second sub-box 12 can also be hollow structures with one side open, and the open side of the first sub-box 11 covers the open side of the second sub-box 12.

[0091] In the battery device 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 device 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 device 100 may also include other structures, for example, the battery device 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0092] In some embodiments of this application, please refer to Figure 3 and Figure 4 , Figure 3 is a schematic diagram of the exploded structure of the battery cell 20 of this embodiment, Figure 4 Schematic diagram of the structure of the battery cell 20 of this embodiment. This embodiment provides a battery cell 20, including a housing 201, an electrode assembly 202, an insulating member 203 and an electrolyte. The electrode assembly 202 is accommodated in the housing 201. The insulating member 203 is arranged between the housing 201 and the electrode assembly 202. The electrolyte is arranged in the housing 201.

[0093] Please continue to refer to Figure 5 and Figure 6 , Figure 5 is a schematic diagram of the structure of the insulating member 203 in this embodiment, Figure 6 203 is a perspective view of the insulating member 203 in this embodiment. The insulating member 203 is integrally formed, and may include a first side wall 2031 and a first bottom wall 2032. The first side wall 2031 is disposed around the first bottom wall 2032, and together with the first bottom wall 2032, forms a receiving cavity with an opening. The opening of the receiving cavity is disposed opposite to the first bottom wall 2032, at least part of the electrode assembly 202 and at least part of the electrolyte are received in the receiving cavity, and the inner circumference of the first side wall 2031 is a continuous surface.

[0094] For the convenience of distinction, the bottom wall of the insulating member 203 is named as the first bottom wall 2032, the side wall of the insulating member 203 is named as the first side wall 2031, and the area from the first bottom wall 2032 to the opening can be regarded as the first side wall 2031. The inner peripheral surface of the first side wall 2031 is a continuous surface, which means that there is no gap on the first side wall 2031, which can prevent the electrolyte from flowing to the inside of the housing 201.

[0095] In the above embodiment, the insulating member 203 is integrally formed, and after the forming, the inner peripheral surface of the first side wall 2031 is a continuous surface. During the normal use of the battery cell 20, the electrolyte located on the inner side of the insulating member 203 is difficult to flow out from the side wall of the insulating member 203. On the one hand, the electrolyte can be located on the inner side of the insulating member 203 for a longer time, which can more effectively form an infiltration effect on the electrode assembly 202, thereby achieving the purpose of improving the utilization rate of the electrolyte. On the other hand, the carbon powder shed from the negative electrode of the electrode assembly 202 is also difficult to contact the shell 201, which reduces the risk of corrosion to the shell 201, can improve the reliability of the battery cell 20, and can also increase the service life of the battery cell 20. At the same time, the insulating member 203 is integrally formed, which reduces the original folding and hot-melt processes during assembly and improves assembly efficiency.

[0096] In some embodiments of the present application, the insulating member 203 is integrally formed by injection molding. In other embodiments, the insulating member 203 may also be integrally formed by blow molding or integrally formed by compression molding.

[0097] In some embodiments of the present application, still refer to Figure 6 , the first bottom wall 2032 is provided with a first through hole 20321. In some usage scenarios, the battery cell 20 is susceptible to a large degree of vibration, and when some types of battery cells 20 are subjected to a large degree of vibration, the electrolyte originally located on the inner side of the insulating member 203 may flow out from the opening of the insulating member 203 and flow to the inner side of the outer shell 201. Because the battery cell 20 is usually placed in a forward position, the outflowing electrolyte will flow to the bottom of the outer shell 201, and it will be difficult to continue to infiltrate the electrode assembly 202. In other scenarios, the electrolyte may flow to the inner side of the outer shell 201 due to injection deviation, which will also make it difficult for the electrolyte to continue to infiltrate the electrode assembly 202.

[0098] In the above embodiment, by providing the first through hole 20321 on the first bottom wall 2032, the electrolyte flowing to the bottom of the housing 201 can flow back to the inside of the insulating member 203 through the first through hole 20321, and continue to infiltrate the electrode assembly 202, thereby realizing the reuse of the electrolyte. The provision of the first through hole 20321 enables a certain amount of electrolyte to always exist inside the insulating member 203, thereby achieving a good infiltration effect on the electrode assembly 202.

[0099] In some examples, the number of the first through holes 20321 can be multiple. According to the specific usage scenario of the battery cell 20, the number of the first through holes 20321 and the aperture of the first through holes 20321 can be selectively set.

[0100] In some embodiments of this application, please refer to Figure 7, the battery cell 20 also includes a filter membrane 204, which is connected to the side of the first bottom wall 2032 away from the accommodating cavity and covers the first through hole 20321. When the first through hole 20321 is provided on the first bottom wall 2032, the electrolyte flowing to the bottom position of the shell 201 can flow back to the insulating member 203 through the first through hole 20321, thereby re-wetting the electrode assembly 202. However, under normal use of the battery cell 20, the electrolyte will also flow from the inside of the insulating member 203 to the outside thereof through the first through hole 20321. In the above embodiment, under normal use of the battery cell 20, by providing the filter membrane 204 covering the first through hole 20321, the speed at which the electrolyte flows from the inside of the insulating member 203 to the outside thereof can be slowed down, so that the electrolyte can be located on the inside of the insulating member 203 for a longer time, thereby achieving a better effect of wetting the electrode assembly 202.

[0101] In some other embodiments, the filter membrane 204 may also be connected to one side of the first bottom wall 2032 in the accommodating cavity and cover the first through hole 20321. With this arrangement, the filter membrane 204 can still slow down the flow of electrolyte from the inside of the insulating member 203 to the outside thereof, thereby achieving a better effect of wetting the electrode assembly 202.

[0102] In some embodiments of the present application, the housing 201 may include a housing 2011 and an end cap 2012. The housing 2011 includes a second side wall 20111 and a second bottom wall 20112, wherein the second side wall 20111 is disposed around the second bottom wall 20112, one end of the second side wall 20111 is connected to the second bottom wall 20112, and the other end of the second side wall 20111 is connected to the end cap 2012. The filter membrane 204 is in direct contact with the second bottom wall 20112.

[0103] The shell 2011 and the end cover 2012 together form a cavity structure. For the convenience of distinction, the side wall of the shell 2011 is named as the second side wall 20111, and the bottom wall of the shell 2011 is named as the second bottom wall 20112.

[0104] The bottom area of ​​the shell 2011 is usually provided with an arc transition portion 20113, that is, an arc angle structure formed in the connection area between the second side wall 20111 and the second bottom wall 20112. During the assembly process of the shell 201 and the insulating member 203, the arc transition portion 20113 will cause certain interference, making it difficult for the insulating member 203 to be placed in the shell 201 in full contact with the bottom wall of the shell 201, resulting in a gap between the insulating member 203 and the second bottom wall 20112, and the electrolyte will be enriched in the gap, thereby reducing the infiltration effect of the electrolyte on the electrode assembly 202. In the above embodiment, the filter membrane 204 is connected to the side of the first bottom wall 2032 away from the accommodating cavity, and is in direct contact with the second bottom wall 20112. This setting can reduce the gap between the insulating member 203 and the bottom wall of the shell 201, thereby reducing the ineffective enrichment area of ​​the electrolyte, and improving the infiltration effect of the electrolyte on the electrode assembly 202, thereby achieving the purpose of improving the utilization rate of the electrolyte.

[0105] In some embodiments of this application, please refer to Figure 8 The housing 2011 further includes an arc transition portion 20113, and the second side wall 20111 and the second bottom wall 20112 are connected via the arc transition portion 20113. The thickness direction of the first bottom wall 2032 is the first direction. Along the first direction, the thickness of the filter membrane 204 is d 1 , the size of the arc transition portion 20113 is d 2 , d 1 ≥d 2 In this embodiment, the thickness of the filter membrane 204 is set to be greater than or equal to the size of the arc transition portion 20113 in the first direction, so that the insulating member 203 can avoid the arc transition portion 20113 in the shell 2011, reduce the interference of the arc transition portion 20113, and thus make it easier to assemble the insulating member 203 with the shell 2011, thereby improving the assembly efficiency of the battery cell 20.

[0106] In some embodiments of the present application, the thickness of the filter membrane 204 is 0.5 mm to 3 mm. The thickness of the filter membrane 204 is selected to be a specific size within this size range, which can achieve a good effect.

[0107] In some embodiments of the present application, the thickness direction of the first bottom wall 2032 is still taken as the first direction, and the projection area of ​​the filter membrane 204 on the projection plane perpendicular to the first direction is S 1 , the projected area of ​​the electrode assembly 202 is S 2 , S 1 ≥80%*S 2When the electrode assembly 202 and the insulating member 203 are assembled as a whole with the housing 201, the closer the projection area of ​​the filter membrane 204 is to the projection area of ​​the electrode assembly 202, the smaller the gap between the second bottom wall 20112 and the first bottom wall 2032 is, and the less electrolyte can be enriched in the gap. The electrolyte can flow more to the inner side of the insulating member 203, which can have a better infiltration effect on the electrode assembly 202 and a higher utilization rate of the electrolyte.

[0108] In some examples, better effects can be achieved when the projection area of ​​the filter membrane 204 is set to be equal to the projection area of ​​the electrode assembly 202. In this example, since the gap between the first bottom wall 2032 and the second bottom wall 20112 is smaller, on the one hand, the utilization rate of the electrolyte can be improved; on the other hand, the uneven distribution of the electrolyte enrichment area can be reduced, resulting in uneven force on the electrode assembly 202, thereby reducing the possible local deformation of the electrode assembly 202, resulting in a decrease in the overall service life of the battery cell 20.

[0109] In some examples, in order to reduce the risk of overlap between the housing 201 and the electrode assembly 202, a bottom support plate is usually provided between the first bottom wall 2032 and the second bottom wall 20112. When an embodiment with a filter membrane 204 is adopted, the filter membrane 204 can be used to replace the bottom support plate to reduce the risk of overlap between the housing 201 and the electrode assembly 202. The elimination of the bottom support plate can reduce the use of materials of the battery cell 20 and reduce the related assembly process, which can effectively improve the assembly efficiency of the battery cell 20 and improve its economy. The greater the thickness of the filter membrane 204, or the larger the area of ​​the filter membrane 204 on the projection surface perpendicular to the first direction, the better the performance of isolating the housing 201 and the electrode assembly 202, and the lower the risk of overlap between the housing 201 and the electrode assembly 202.

[0110] In some embodiments of the present application, the filter membrane 204 includes a first side surface and a second side surface, the first side surface faces the insulating member 203, and the second side surface faces away from the insulating member 203. The filter membrane 204 may be a one-way membrane, which allows the electrolyte to flow from the side where the second side surface is located to the side where the first side surface is located. In the above embodiment, the filter membrane 204 is a one-way membrane. When the battery cell 20 is placed and used normally, it is difficult for the electrolyte to flow from the inside of the insulating member 203 to the outside thereof; when the electrolyte flows to the inside of the housing 201, it can flow to the inside of the insulating member 203 through the one-way membrane and continue to infiltrate the electrode assembly 202.

[0111] In some embodiments of the present application, the filter membrane 204 may be made of polytetrafluoroethylene (PTFE), polyolefin (PO) or nylon 66 (N66). When using such materials, the filter membrane 204 can form a unidirectional membrane suitable for the battery cell 20 to achieve the purpose of improving the utilization rate of the electrolyte.

[0112] In some embodiments of the present application, the filter membrane 204 is connected to the first bottom wall 2032 by hot melting or bonding. The connection between the filter membrane 204 and the first bottom wall 2032 can be achieved by any of the methods in the above embodiments.

[0113] In some embodiments of the present application, the first side wall 2031 includes two first sub-side walls 20311 arranged opposite to each other along the second direction and two second sub-side walls 20312 arranged opposite to each other along the third direction. The thickness direction of the first bottom wall 2032 is still taken as the first direction, wherein the first direction, the second direction and the third direction are perpendicular to each other. A groove 203121 is formed on the inner surface of the second sub-side wall 20312. The electrode assembly 202 includes a bending area 2021, and at least a portion of the bending area 2021 is located in the groove 203121.

[0114] The two first sub-side walls 20311 and the two second sub-side walls 20312 together form the first side wall 2031 of the insulating member 203. In the above embodiment, a groove 203121 is formed on the inner surface of the second sub-side wall 20312, and the bending area 2021 of the electrode assembly 202 is at least partially located in the groove 203121, so that the insulating member 203 can better cover the electrode assembly 202.

[0115] In some embodiments of the present application, the outer surface area of ​​the first sub-sidewall 20311 is larger than the outer surface area of ​​the second sub-sidewall 20312. The groove 203121 is provided on the second sub-sidewall 20312 with a relatively smaller outer surface area to match and assemble the conventionally used electrode assembly 202.

[0116] In some other embodiments, the outer surface area of ​​the first sub-sidewall 20311 may also be less than or equal to the outer surface area of ​​the second sub-sidewall 20312 .

[0117] In some embodiments of the present application, a plurality of electrode assemblies 202 are provided, and the plurality of electrode assemblies 202 are arranged along the second direction. The insulating member 203 accommodates the plurality of electrode assemblies 202, and in the region of each accommodated electrode assembly 202, a plurality of grooves 203121 are formed on the inner surface of each second sub-side wall 20312, and the grooves 203121 correspond one to one with the electrode assemblies 202. In this embodiment, a plurality of grooves 203121 are formed on the inner surface of the second sub-side walls 20312 arranged opposite to each other, and two opposite grooves 203121 correspond to one electrode assembly 202, and the bending areas 2021 on the opposite side edges of the electrode assembly 202 are at least partially located in the corresponding grooves 203121. By providing a plurality of electrode assemblies 202, different battery cells 20 are formed to meet the needs of different usage scenarios.

[0118] In some examples, the contact areas between adjacent grooves 203121 may be passivated to reduce the risk of damaging the electrode assembly 202 during assembly due to the contact areas being too sharp.

[0119] In some embodiments of this application, please refer to Figures 9 to 11 , Fig. 9 FIG. 2 is a top view of a battery cell 20 in this embodiment. Fig.10 for Fig. 9 AA section view, Fig.11 for Fig.10 A partial enlarged view at C. A second through hole 203122 is provided on the second sub-side wall 20312, and two adjacent grooves 203121 are connected through the second through hole 203122. The second through hole 203122 allows the electrolyte to infiltrate the multiple electrode assemblies 202, which can effectively improve the utilization rate of the electrolyte.

[0120] In some examples, the areas where two adjacent electrode assemblies 202 are located are connected, and the adjacent electrode assemblies 202 are limited only by the grooves 203121 formed on the second sub-side wall 20312. In this example, although the electrolyte can flow in the area where two adjacent electrode assemblies 202 are located through the connected area, so that the electrolyte can infiltrate each other among the multiple electrode assemblies 202, electrolyte enrichment may still occur at the edge of the groove 203121, which not only reduces the utilization rate of the electrolyte, but also causes local enrichment of the electrolyte, resulting in the bending area 2021 of the electrode assembly 202 being subjected to greater force than other areas, resulting in uneven force. In the case of a long time, the electrode assembly 202 may be deformed due to uneven force, resulting in the service life of the electrode assembly 202 being affected. The provision of the second through hole 203122 can enable the electrolyte to better infiltrate each other among the multiple electrode assemblies 202 and reduce the uneven force of the electrode assembly 202.

[0121] In other examples, the regions where two adjacent electrode assemblies 202 are located are not connected, but are only connected through the second through holes 203122 . In this case, the second through holes 203122 can achieve the effect of mutual infiltration of the electrolyte between the multiple electrode assemblies 202 .

[0122] In some examples, the number of second through holes 203122 may include a plurality.

[0123] In some embodiments of the present application, along the first direction, the second sub-side wall 20312 has a first edge 203124 away from the first bottom wall 2032, and the distance between the second through hole 203122 and the first edge 203124 is greater than the distance between the second through hole 203122 and the first bottom wall 2032. In this embodiment, the second through hole 203122 is disposed in the middle and lower region of the second sub-side wall 20312. When the electrolyte is less, the second through hole 203122 can also well support the electrolyte to flow between adjacent electrode assemblies 202, thereby achieving mutual infiltration between the multiple electrode assemblies 202.

[0124] In some embodiments of this application, please refer to Fig. 9 , Fig.12 and Fig.13 , Fig. 9 is a top view of the battery cell 20 in this embodiment, Fig.12 for Fig. 9 BB cross-sectional view, Fig.13 for Fig.12 A partial enlarged view at D. The first side wall 2031 includes two first sub-side walls 20311 arranged opposite to each other along the second direction and two second sub-side walls 20312 arranged opposite to each other along the third direction. The thickness direction of the first bottom wall 2032 is the first direction, wherein the first direction, the second direction and the third direction are perpendicular to each other. A first guide surface 203111 is provided at one end of the first sub-side wall 20311 away from the first bottom wall 2032, and the first guide surface 203111 is connected to the inner surface of the first sub-side wall 20311. During the assembly process of the electrode assembly 202 and the insulating member 203, the first guide surface 203111 can guide the insulating member 203 to be gradually accommodated in the insulating member 203, which can effectively improve the assembly of the two.

[0125] In some other embodiments of the present application, the first side wall 2031 includes two first sub-side walls 20311 arranged opposite to each other along the second direction and two second sub-side walls 20312 arranged opposite to each other along the third direction. The thickness direction of the first bottom wall 2032 is the first direction, wherein the first direction, the second direction and the third direction are perpendicular to each other. A second guide surface 203123 is provided at one end of the second sub-side wall 20312 away from the first bottom wall 2032, and the second guide surface 203123 is connected to the inner surface of the second sub-side wall 20312. The provision of the second guide surface 203123 can facilitate the assembly of the insulating member 203 and the electrode assembly 202, thereby improving the assembly efficiency.

[0126] In some other embodiments of the present application, the first side wall 2031 includes two first sub-side walls 20311 arranged opposite to each other along the second direction and two second sub-side walls 20312 arranged opposite to each other along the third direction. The thickness direction of the first bottom wall 2032 is the first direction, wherein the first direction, the second direction and the third direction are perpendicular to each other. A first guide surface 203111 is provided at one end of the first sub-side wall 20311 away from the first bottom wall 2032, and a second guide surface 203123 is provided at one end of the second sub-side wall 20312 away from the first bottom wall 2032. In this embodiment, the edge position of the insulating member 203 away from the first bottom wall 2032 is continuously provided with a guide surface, which can make the assembly of the insulating member 203 and the electrode assembly 202 more convenient and more efficient.

[0127] In some embodiments of the present application, the minimum thickness of the first side wall 2031 is 0.1 mm to 0.5 mm; the minimum thickness of the first bottom wall 2032 is 0.1 mm to 0.5 mm. By selecting the size within this size range, the purpose of use requirements can be met and the overall economy of the battery cell 20 can be improved.

[0128] In some embodiments of the present application, the material of the insulating member 203 may be polypropylene or polyethylene.

[0129] According to some embodiments of the present application, a battery cell 20 is provided, comprising a housing 201, an electrode assembly 202, an insulating member 203, an electrolyte and a filter membrane 204. The electrode assembly 202 is accommodated in the housing 201, the insulating member 203 is arranged between the housing 201 and the electrode assembly 202, and the electrolyte is arranged in the housing 201. The insulating member 203 comprises a first side wall 2031 and a first bottom wall 2032, the first side wall 2031 is arranged around the first bottom wall 2032, and together with the first bottom wall 2032, forms a receiving cavity with an opening, the opening is arranged opposite to the first bottom wall 2032, at least part of the electrode assembly 202 and at least part of the electrolyte are accommodated in the receiving cavity, the insulating member 203 is integrally formed, and the inner peripheral surface of the first side wall 2031 is a continuous surface. The first bottom wall 2032 is provided with a first through hole 20321, and the filter membrane 204 is connected to the side of the first bottom wall 2032 away from the accommodating cavity and is arranged to cover the first through hole 20321. The filter membrane 204 and the first bottom wall 2032 are connected by hot melting or bonding.

[0130] The housing 201 includes a shell 2011 and an end cap 2012. The shell 2011 includes a second side wall 20111 and a second bottom wall 20112. The second side wall 20111 is arranged around the second bottom wall 20112. One end of the second side wall 20111 is connected to the second bottom wall 20112. The other end of the second side wall 20111 is connected to the end cap 2012. The filter membrane 204 is in direct contact with the second bottom wall 20112. The shell 2011 also includes an arc transition portion 20113. The second side wall 20111 and the second bottom wall 20112 are connected through the arc transition portion 20113. Along the first direction, the thickness of the filter membrane 204 is greater than the size of the arc transition portion 20113. The thickness of the filter membrane 204 can be 0.5 mm to 3 mm. The filter membrane 204 can be made of polytetrafluoroethylene, polyolefin or nylon to form a unidirectional membrane.

[0131] The first side wall 2031 includes two first sub-side walls 20311 arranged opposite to each other along the second direction and two second sub-side walls 20312 arranged opposite to each other along the third direction. A plurality of grooves 203121 are formed on the inner surface of the second sub-side wall 20312. A plurality of electrode assemblies 202 are provided. The plurality of electrode assemblies 202 are arranged along the second direction. Each electrode assembly 202 corresponds to a groove 203121 one by one, and the bending area 2021 of the electrode assembly 202 is at least partially located in the groove 203121. A second through hole 203122 is provided on the second sub-side wall 20312. Two adjacent grooves 203121 are connected through the second through hole 203122. The second through hole 203122 is used to achieve mutual wetting between the plurality of electrode assemblies 202.

[0132] A second guide surface 203123 is provided at one end of the second sub-side wall 20312 away from the first bottom wall 2032. The second guide surface 203123 is connected to the inner surface of the second sub-side wall 20312 to guide the assembly of the electrode assembly 202 and the insulating member 203. The minimum thickness of the first side wall 2031 is 0.1 mm to 0.5 mm; the minimum thickness of the first bottom wall 2032 is 0.1 mm to 0.5 mm. The material of the insulating member 203 is polypropylene or polyethylene.

[0133] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: shell; an electrode assembly, contained in the housing; an insulating member, disposed between the housing and the electrode assembly; an electrolyte disposed in the housing; Among them, the insulating part is integrally injection-molded, and the insulating part includes a first side wall and a first bottom wall. The first side wall is arranged around the first bottom wall, and together with the first bottom wall, forms a accommodating cavity with an opening, and the opening is arranged opposite to the first bottom wall. At least part of the electrode assembly and at least part of the electrolyte are accommodated in the accommodating cavity, and the inner peripheral surface of the first side wall is a continuous surface.

2. The battery cell according to claim 1, characterized in that: The first bottom wall is provided with a first through hole.

3. The battery cell according to claim 2, characterized in that: The battery cell further includes a filter membrane, which is connected to a side of the first bottom wall facing away from the accommodating cavity and covers the first through hole.

4. The battery cell according to claim 3, characterized in that: The housing comprises a shell and an end cover, the shell comprises a second side wall and a second bottom wall, the second side wall is arranged around the second bottom wall, one end of the second side wall is connected to the second bottom wall, and the other end of the second side wall is connected to the end cover; The filter membrane is in direct contact with the second bottom wall.

5. The battery cell according to claim 4, characterized in that: The housing further comprises an arc transition portion, and the second side wall and the second bottom wall are connected by the arc transition portion; The thickness direction of the first bottom wall is a first direction. Along the first direction, the thickness of the filter membrane is d1, and the size of the arc transition portion is d2, where d1≥d2.

6. The battery cell according to claim 3, characterized in that: The thickness of the filter membrane is 0.5 mm to 3 mm.

7. The battery cell according to claim 3, characterized in that: The thickness direction of the first bottom wall is the first direction. On the projection plane perpendicular to the first direction, the projection area of ​​the filter membrane is S1, the projection area of ​​the electrode assembly is S2, and S1≥80%*S2.

8. The battery cell according to claim 3, characterized in that: The filter membrane includes a first side and a second side, the first side faces the insulating member, and the second side faces away from the insulating member. The filter membrane is a unidirectional membrane that allows the electrolyte to flow from the second side to the first side.

9. The battery cell according to claim 3, characterized in that: The filter membrane is made of polytetrafluoroethylene, polyolefin or nylon.

10. The battery cell according to claim 3, characterized in that: The filter membrane is connected to the first bottom wall by thermal melting or bonding.

11. The battery cell according to claim 1, characterized in that: The first side wall includes two first sub-side walls arranged opposite to each other along the second direction and two second sub-side walls arranged opposite to each other along the third direction; the thickness direction of the first bottom wall is the first direction, and the first direction, the second direction and the third direction are perpendicular to each other; A groove is formed on the inner surface of the second sub-side wall, and the electrode assembly includes a bending area, at least a portion of the bending area is located in the groove.

12. The battery cell according to claim 11, characterized in that: An outer surface area of ​​the first sub-sidewall is greater than an outer surface area of ​​the second sub-sidewall.

13. The battery cell according to claim 11, characterized in that: The electrode assembly is provided in plurality, and the plurality of electrode assemblies are arranged along the second direction; A plurality of grooves are formed on the inner surface of each of the second sub-side walls, and the grooves correspond to the electrode assemblies one by one.

14. The battery cell according to claim 13, characterized in that: The second sub-side wall is provided with a second through hole, and two adjacent grooves are connected through the second through hole.

15. The battery cell according to claim 14, characterized in that: Along the first direction, the second sub-side wall has a first edge away from the first bottom wall, and the distance between the second through hole and the first edge is greater than the distance between the second through hole and the first bottom wall.

16. The battery cell according to claim 1, characterized in that: The first side wall includes two first sub-side walls arranged opposite to each other along the second direction and two second sub-side walls arranged opposite to each other along the third direction; the thickness direction of the first bottom wall is the first direction, and the first direction, the second direction and the third direction are perpendicular to each other; A first guide surface is provided at one end of the first sub-side wall away from the first bottom wall, and the first guide surface is connected to the inner surface of the first sub-side wall; and / or a second guide surface is provided at one end of the second sub-side wall away from the first bottom wall, and the second guide surface is connected to the inner surface of the second sub-side wall.

17. The battery cell according to claim 1, characterized in that: The minimum thickness of the first side wall is 0.1 mm to 0.5 mm; the minimum thickness of the first bottom wall is 0.1 mm to 0.5 mm.

18. The battery cell according to claim 1, characterized in that: The insulating member is made of polypropylene or polyethylene.

19. A battery device, characterized in that: A battery cell comprising the battery cell according to any one of claims 1 to 18.

20. An electrical device, characterized in that: A battery device comprising the battery device of claim 19.

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