Housing, battery cell, battery device, and electric device

Abstract

The utility model provides a shell, a battery monomer, a battery device and a power utilization device, the battery monomer comprises the shell and an electrode assembly, the electrode assembly is accommodated in the shell, the shell comprises a reinforcing piece and a first wall, the reinforcing piece is arranged on one side of the first wall along the thickness direction, the first wall comprises a first sub-part and a second sub-part, and the first sub-part is arranged on the first wall. The reinforcer is connected with the first sub-part and the second sub-part in a welded mode to form a weld joint, and the weld joint is arranged on the surface of the side, back to the reinforcer, of the first wall. According to the battery monomer provided by the invention, the structural strength of the weld joint on the first wall of the shell is improved, and the risk of cracking of the shell at the weld joint is reduced, so that the reliability of the battery monomer is improved.

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 device, and an electrical device. Background Art

[0002] Batteries are widely used in electronic devices such as mobile phones, laptops, electric vehicles, electric airplanes, electric boats, electric toy cars, electric toy boats, electric toy airplanes and power tools, etc.

[0003] In the development of battery cell technology, in addition to improving the performance of battery cells, the reliability of battery cells is also an issue that needs to be considered. Therefore, how to improve the reliability of battery cells is an issue that needs to be continuously improved in battery cell technology. Utility Model Content

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

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

[0006] In the first aspect, the battery cell provided in the embodiment of the present application includes a shell and an electrode assembly, the electrode assembly is accommodated in the shell, the shell includes a reinforcement and a first wall, the reinforcement is arranged on one side of the first wall along the thickness direction, the first wall includes a first sub-section and a second sub-section, the reinforcement is welded to the first sub-section and the second sub-section, respectively, to form a weld, and the weld is arranged on the surface of the first wall on the side facing away from the reinforcement.

[0007] The battery cell provided in the embodiment of the present application is beneficial to improving the structural strength of the weld on the first wall of the shell and reducing the risk of cracking of the shell at the weld by arranging the weld on the surface of the first wall facing away from the reinforcement, and arranging the first sub-portion and the second sub-portion to be welded to the reinforcement respectively. This is beneficial to improving the reliability performance of the battery cell.

[0008] According to some embodiments of the present application, the material of the first wall includes titanium alloy or steel.

[0009] In the above solution, by setting the material of the first wall to include titanium alloy or steel, it is beneficial to improve the structural strength of the shell and reduce the risk of damage to the shell. Especially in the case of thermal runaway of the battery cell, the first wall has a strong tensile strength, which is beneficial to reduce the risk of damage to the first wall, thereby reducing the risk of further spread of thermal runaway of the battery cell, and is beneficial to further improve the reliability performance of the battery cell.

[0010] According to some embodiments of the present application, the thickness e of the first wall satisfies: 0.075≤e≤0.4 mm.

[0011] In the above solution, setting 0.075≤e≤0.4mm is beneficial to improving the structural strength of the first wall while reducing the difficulty of welding the first sub-section and the second sub-section to the reinforcement respectively.

[0012] According to some embodiments of the present application, 0.15≤e≤0.3 mm.

[0013] In the above solution, setting 0.15≤e≤0.3mm is beneficial to further improve the structural strength of the first wall, and is also beneficial to further reduce the difficulty of welding the first sub-section and the second sub-section to the reinforcement respectively.

[0014] According to some embodiments of the present application, the electrode assembly includes a positive electrode plate, the positive electrode plate includes a positive electrode active material capable of reversibly extracting and inserting metal ions, and the positive electrode active material includes a nickel-containing compound.

[0015] In the above scheme, the positive electrode active material is provided with a nickel element compound portion, which is beneficial to improving the energy density of the battery cell and improving the cycle life of the battery cell. By providing a reinforcement, the structural strength of the weld of the first wall is improved. In the case of thermal runaway of the battery cell, the risk of weld cracking is reduced, and the risk of further spread of thermal runaway of the battery cell is further reduced, so as to improve the reliability performance of the battery cell.

[0016] According to some embodiments of the present application, the electrode assembly further includes a negative electrode plate, the negative electrode plate includes a negative electrode active material capable of reversibly extracting and embedding metal ions, and the negative electrode active material includes a silicon-based material.

[0017] In the above scheme, the negative electrode active material is provided to include a silicon-based material, which is beneficial to improving the energy density of the battery cell. By providing the first sub-section and the second sub-section to be respectively welded to the reinforcement, it is beneficial to reduce the risk of weld cracking, thereby reducing the risk of further spread of thermal runaway of the battery cell, and improving the reliability performance of the battery cell.

[0018] According to some embodiments of the present application, the reinforcement and the first wall are both made of titanium alloy.

[0019] In the above scheme, the materials used to form the first wall and the reinforcement include titanium alloy, which is beneficial to improving the structural strength of the first wall, reducing the risk of further spread of thermal runaway of the battery cell, and improving the strength of the welding connection between the reinforcement and the first sub-section and the second sub-section respectively, and facilitating the smooth progress of the welding process.

[0020] According to some embodiments of the present application, the reinforcement and the first wall are both made of steel.

[0021] In the above solution, steel also has high structural strength. By setting the materials of the first wall and the reinforcement to include steel, it is beneficial to improve the structural strength of the first wall, reduce the risk of further spread of thermal runaway of the battery cell, and help improve the strength of the welding connection between the reinforcement and the first sub-section and the second sub-section respectively, and facilitate the smooth progress of the welding process.

[0022] According to some embodiments of the present application, the thickness d of the reinforcement satisfies: 0.2 mm ≤ d ≤ 1 mm.

[0023] In the above solution, setting 0.2mm≤d≤1mm is beneficial to reducing the space occupied by the reinforcement, thereby improving the energy density of the battery cell, and reducing the risk of welding through the reinforcement and the first sub-section or the reinforcement and the second sub-section.

[0024] According to some embodiments of the present application, the weld includes a first weld and a second weld. The reinforcement is welded to the first sub-section to form the first weld, and the reinforcement is welded to the second sub-section to form the second weld. The first weld and the second weld are spaced apart.

[0025] In the above scheme, it is helpful to reduce the risk of the reinforcement being welded through, and to reduce the size of the weld formed after welding and its protruding distance in the direction away from the reinforcement, so as to reduce the risk of the weld damaging other structural parts.

[0026] According to some embodiments of the present application, the reinforcement, the first sub-portion, and the second sub-portion are connected by welding to form a weld.

[0027] In the above scheme, the reinforcement, the first sub-section and the second sub-section are welded together, which is beneficial to further improve the welding strength between the reinforcement and the first wall, further reduce the risk of cracking of the weld of the first wall, and simplify the welding process of the first sub-section, the second sub-section and the reinforcement.

[0028] According to some embodiments of the present application, an electrode assembly includes an electrode body and a tab, the tab extending from an end of the electrode body along a first direction, the electrode body including two first surfaces opposing each other along a second direction and two second surfaces opposing each other along a third direction, the first surface connecting the two second surfaces, the first direction, the second direction, and the third direction being perpendicular to each other, the area of ​​the first surface being greater than the area of ​​the second surface, and the first wall being disposed opposite the second surface.

[0029] In the above solution, the first wall and the second surface are arranged opposite to each other, which is beneficial to reducing the expansion force borne by the first wall when the electrode assembly expands, and further beneficial to reducing the risk of weld cracking.

[0030] According to some embodiments of the present application, the electrode assembly is wound, the second surface is arc-shaped and convex toward the first wall, the battery cell includes at least two electrode assemblies, and the at least two electrode assemblies are arranged along the second direction. The first wall and the two second surfaces of two adjacent electrode assemblies along the second direction enclose a virtual space, and the reinforcement member is disposed within the virtual space.

[0031] In the above solution, the virtual space cannot be used by the electrode assembly. By arranging the reinforcement in the virtual space, it is beneficial to reduce the space inside the battery cell that is additionally occupied by the reinforcement, which is beneficial to improving the battery energy density.

[0032] According to some embodiments of the present application, the housing includes two first walls, and the two first walls are arranged opposite to each other along the thickness direction.

[0033] In the above solution, the shell can be completed by splicing two "U"-shaped groove structures and welding them together on the two first walls. In this way, the "U"-shaped groove structure only needs to undergo two simple bends, which is conducive to simplifying the processing technology of the battery cell shell.

[0034] According to some embodiments of the present application, the reinforcement is provided on a side of the first wall facing the electrode assembly.

[0035] In the above solution, welding the first wall and the reinforcement can be performed from the exterior of the housing, facilitating the welding of the first and second subsections to the reinforcement. Furthermore, the reinforcement is positioned inside the housing, reducing the risk of scratching other external structures of the battery cell.

[0036] According to some embodiments of the present application, the housing includes a second wall intersecting with the first wall, the first wall has an avoidance groove, and a portion of the reinforcement is disposed in the avoidance groove.

[0037] In the above scheme, there is no need to reserve additional space for the reinforcement at the end of the reinforcement facing the second wall, which is beneficial to improving the energy density of the battery cell. The cooperation between the avoidance groove and the reinforcement can provide a certain positioning effect for the second wall, facilitate the assembly of the second wall and the first wall, and help simplify the assembly process of the battery cell.

[0038] In the second aspect, the shell provided in the embodiment of the present application includes a first wall and a reinforcement, the first wall includes a first sub-section and a second sub-section, the reinforcement is arranged on one side of the first wall along the thickness direction, the reinforcement is welded to the first sub-section and the second sub-section respectively to form a weld, and the weld is arranged on the side of the first wall facing away from the reinforcement.

[0039] In a third aspect, the battery device provided in an embodiment of the present application includes the battery cell provided in any of the above embodiments.

[0040] The battery device provided in the embodiment of the present application has the same technical effects as any of the battery cells provided in any of the above embodiments, and thus will not be described in detail here.

[0041] In a fourth aspect, the electrical device provided in the embodiments of the present application includes the battery device provided in the above embodiments, and the battery device is used to provide electrical energy.

[0042] The electric device provided in the embodiment of the present application has the same technical effects as the battery device provided in the above embodiment, and thus will not be described in detail here.

[0043] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. 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 relevant drawings can be obtained based on these drawings without paying any creative work.

[0045] Figure 1 A schematic diagram of the structure of a vehicle provided in an embodiment of the present application;

[0046] Figure 2 A schematic diagram of the structure of a battery device provided in an embodiment of the present application;

[0047] Figure 3 A schematic structural diagram of a battery module in a battery device according to an embodiment of the present application;

[0048] Figure 4 A schematic diagram of the explosion structure of a battery cell provided in an embodiment of the present application;

[0049] Figure 5 A schematic diagram of the structure of the outer shell of a battery cell provided in an embodiment of the present application;

[0050] Figure 6 A front view of a battery cell provided in an embodiment of the present application;

[0051] Figure 7 for Figure 6 Schematic diagram of the cross-sectional structure along AA;

[0052] Figure 8 for Figure 7 A partial enlarged view of point B in the middle;

[0053] Figure 9A schematic diagram of a portion of the structure of the outer shell of a battery cell provided in an embodiment of the present application;

[0054] Figure 10 Another schematic diagram of the structure of the outer shell of the battery cell provided in the embodiment of the present application;

[0055] Figure 11 A schematic structural diagram of the second wall in a battery cell provided in an embodiment of the present application;

[0056] Figure 12 for Figure 11 A partial enlarged view of point C in the middle.

[0057] In the drawings, the figures are not necessarily drawn to scale.

[0058] Description of reference numerals:

[0059] 1- Vehicle;

[0060] 10-battery device; 111-first sub-box; 112-second sub-box; 11-box; 1a-motor; 1b-controller;

[0061] 20-battery module;

[0062] 30 - battery cell; 31 - housing; 31a - weld; 311a - first weld; 312a - second weld; 311 - housing; 312 - end cap; 313 - first wall; 3131 - first subsection; 3132 - second subsection; 314 - reinforcement; 315 - second wall; 315a - avoidance groove; 32 - electrode assembly; 321 - electrode body; 321a - first surface; 321b - second surface; 322 - tab; 33 - electrode terminal;

[0063] S-virtual space;

[0064] X-first direction; Y-second direction; Z-third direction; M-thickness direction. DETAILED DESCRIPTION

[0065] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0066] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. 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" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" 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-secondary relationship.

[0067] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0068] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0069] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0070] The term "multiple" in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0071] The battery apparatus mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assemblies may include multiple battery cells, which are connected in series, parallel, or hybrid via a busbar.

[0072] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells. For example, the battery cell assembly may be a battery module, which is a battery module formed by arranging and securing multiple battery cells to form a single module. For example, a battery module may be formed by bundling multiple battery cells with cable ties.

[0073] 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 housed in the case.

[0074] 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.

[0075] As an example, the battery cell assembly may also be housed in the box by directly fixing the plurality of battery cells to the box.

[0076] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0077] In some embodiments, the battery device may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0078] 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.

[0079] 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-acid batteries, and the like.

[0080] A battery cell typically includes an electrode assembly. This assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of a battery cell, active ions (such as lithium ions) are inserted and removed between the positive and negative electrodes. The separator, located between the positive and negative electrodes, prevents short circuits between the positive and negative electrodes while allowing the active ions to pass through.

[0081] In some embodiments, the positive electrode may be a positive electrode sheet, which 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.

[0082] 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 provided on either or both of the two facing surfaces of the positive electrode current collector.

[0083] 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, stainless steel, copper, aluminum, carbon electrode, carbon, nickel 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.).

[0084] 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 battery cells may also be used.

[0085] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0086] As an example, the negative electrode current collector may be a metal foil or a composite current collector. For example, the metal foil may be silver-plated aluminum, silver-plated stainless steel, stainless steel, copper, aluminum, carbon electrode, carbon, nickel, or titanium.

[0087] In some embodiments, the negative electrode current collector has two opposite surfaces in its thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0088] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells that is well 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, 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 battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0089] In some embodiments, the diaphragm is an isolation membrane. The present application has no particular limitation on the type of isolation membrane, and any known isolation membrane with a porous structure having good chemical stability and mechanical stability can be selected.

[0090] As an example, the primary 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 particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separator can be a separate component positioned between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes.

[0091] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode, and serves to transport ions and isolate the positive and negative electrodes.

[0092] 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.

[0093] In some embodiments, the electrode assembly is a laminate structure.

[0094] In some embodiments, a battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (e.g., polypropylene), a composite metal housing (e.g., a copper-aluminum composite housing), or an aluminum-plastic film.

[0095] In some embodiments, the housing includes an end cap and a shell. The shell has an opening, and the end cap closes the opening to form a sealed space for accommodating the electrode assembly, electrolyte, and other substances. The shell may have one or more openings. One or more end caps may also be provided.

[0096] In some embodiments, the housing is provided with at least one electrode terminal, which is electrically connected to a tab of the electrode assembly. The electrode terminal may be directly connected to the tab or indirectly connected to the tab via a current collector. The electrode terminal may be provided on an end cap or on the housing.

[0097] In some embodiments, the housing is provided with an explosion-proof valve for releasing the internal pressure of the battery cell.

[0098] 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, and a polygonal battery. The polygonal battery is, for example, a hexagonal battery, etc. There is no special limitation in the embodiments of the present application.

[0099] During the manufacturing process of battery cell shells, some materials cannot be stretched into a cylindrical structure. Instead, they must be welded together to form two or more sub-sections. However, the welds formed by welding the different sub-sections are prone to cracking. This is especially true during the recycling process of the battery cell, where the electrode assembly expands, exerting a certain amount of expansion force on the weld, further increasing the risk of cracking, thus seriously affecting the reliability of the battery cell.

[0100] In view of this, the battery cell provided in the embodiment of the present application includes a shell and an electrode assembly, the electrode assembly is accommodated in the shell, the shell includes a reinforcement and a first wall, the reinforcement is arranged on one side of the first wall along the thickness direction, the first wall includes a first sub-section and a second sub-section, the reinforcement is welded to the first sub-section and the second sub-section respectively to form a weld, and the weld is arranged on the surface of the first wall on the side facing away from the reinforcement.

[0101] The battery cell provided in the embodiment of the present application is beneficial to improving the structural strength of the weld on the outer shell and reducing the risk of cracking of the outer shell at the weld by arranging the weld on the surface of the first wall facing away from the reinforcement, and arranging the first sub-portion and the second sub-portion to be welded to the reinforcement respectively. This is beneficial to improving the reliability performance of the battery cell.

[0102] The technical solutions described in the embodiments of the present application are applicable to a housing, a battery cell including the housing, a battery device including the battery cell, and an electrical device using the battery device.

[0103] The battery device disclosed in the embodiments of the present application can be used, but is not limited to, in electrical devices such as vehicles, ships, or aircraft. The battery device disclosed in the present application can be used to form a power supply system for the electrical device.

[0104] The embodiments of the present application provide an electrical device that uses a battery device as a power source. The electrical device may be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, an electric tool, an electric bicycle, an electric motorcycle, an electric car, a ship, a spacecraft, etc. 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. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0105] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device according to an embodiment of the present application.

[0106] Please refer to Figure 1 , Figure 1Schematic diagram of the structure of the vehicle 1 provided in an embodiment of the present application. The vehicle 1 can be a fuel vehicle, a gas vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, etc. A battery device 10 is provided inside the vehicle 1. The battery device 10 can be provided at the bottom, head, or tail of the vehicle 1. The battery device 10 can be used to power the vehicle 1. For example, the battery device 10 can serve as an operating power source for the vehicle 1 and can be used for the circuit system of the vehicle 1, such as for the working power requirements of the vehicle 1 during startup, navigation, and operation.

[0107] The vehicle 1 may further include a controller 1 b and a motor 1 a . The controller 1 b is used to control the battery device 10 to supply power to the motor 1 a , for example, to meet the power requirements of the vehicle 1 during startup, navigation, and driving.

[0108] In some embodiments of the present application, the battery device 10 can serve not only as an operating power source for the vehicle 1 , but also as a driving power source for the vehicle 1 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1 .

[0109] Please refer to Figure 2 and Figure 3 , Figure 2 This is a schematic diagram of the structure of the battery device 10 provided in an embodiment of the present application. Figure 3 This is a schematic diagram of the structure of the battery module 20 in the battery device 10 provided in an embodiment of the present application. The battery device 10 includes a housing 11 and a battery cell 30, with the battery cell 30 housed within the housing 11. The housing 11 is used to provide a storage space for the battery cell 30, and the housing 11 can adopt a variety of structures. In some embodiments, the housing 11 can include a first sub-housing 111 and a second sub-housing 112, which cover each other and together define a storage space for accommodating the battery cell 30. The second sub-box 112 can be a hollow structure with one end open, and the first sub-box 111 can be a plate-like structure. The first sub-box 111 covers the open side of the second sub-box 112, so that the first sub-box 111 and the second sub-box 112 jointly define a storage space; the first sub-box 111 and the second sub-box 112 can also be hollow structures with one side open, and the open side of the first sub-box 111 covers the open side of the second sub-box 112.

[0110] In the battery device 10, there may be multiple battery cells 30, which may be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 30. The multiple battery cells 30 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery module 20 may be housed within the housing 11. Alternatively, the battery device 10 may comprise multiple battery cells 30 connected in series, in parallel, or in a hybrid connection to form a battery module 20, which is then connected in series, in parallel, or in a hybrid connection to form a single unit housed within the housing 11. The battery device 10 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 30.

[0111] The battery cell 30 may be a secondary battery or a primary battery; the battery cell 30 may also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto.

[0112] Please refer to Figure 4 , Figure 4 Schematic diagram of the explosion structure of the battery cell 30 provided in the embodiment of the present application. Figure 4 As shown, the battery cell 30 includes a housing 31, an electrode assembly 32, and electrode terminals 33. The housing 31 includes a shell 311 and an end cap 312. The shell 311 has an opening, and the end cap 312 closes the opening to isolate the internal environment of the battery cell 30 from the external environment.

[0113] The housing 311 is a component used to cooperate with the end cap 312 to form the internal environment of the battery cell 30, wherein the formed internal environment can be used to accommodate the electrode assembly 32, electrolyte, and other components. The housing 311 and the end cap 312 can be independent components. The housing 311 can be of various shapes and sizes. Specifically, the shape of the housing 311 can be determined according to the specific shape and size of the electrode assembly 32. The housing 311 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0114] The end cap 312 refers to a component that covers the opening of the shell 311 to isolate the internal environment of the battery cell 30 from the external environment. Without limitation, the shape of the end cap 312 can be adapted to the shape of the shell 311 to match the shell 311. Optionally, the end cap 312 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 312 is not easily deformed when squeezed or collided, so that the battery cell 30 can have a higher structural strength and the reliability can also be improved. Functional components such as electrode terminals 33 can be provided on the end cap 312. The electrode terminal 33 can be used to electrically connect to the electrode assembly 32 for outputting or inputting electrical energy of the battery cell 30. The material of the end cap 312 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose any special restrictions on this. In some embodiments, an insulating structure may be provided inside the end cap 312 to isolate the electrical connection components in the housing 311 from the end cap 312 to reduce the risk of short circuits. For example, the insulating structure may be made of plastic, rubber, or the like.

[0115] The electrode assembly 32 is the component where the electrochemical reaction occurs in the battery cell 30. One or more electrode assemblies 32 may be contained in the housing 311. The electrode assembly 32 is mainly formed by winding or stacking the positive electrode sheet and the negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The separator is used to separate the positive electrode sheet and the negative electrode sheet to prevent internal short circuits between the positive electrode sheet and the negative electrode sheet. The portions of the positive electrode sheet and the negative electrode sheet with active materials constitute the electrode body 321 of the electrode assembly 32, and the portions of the positive electrode sheet and the negative electrode sheet without active materials each constitute the tab 322. The positive electrode tab and the negative electrode tab may be located together at one end of the electrode body 321 or respectively at both ends of the electrode body 321. During the charge and discharge process of the battery cell 30, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tab 322 connects to the electrode terminal 33 to form a current loop.

[0116] First, as Figure 4 and Figure 5 As shown, the battery cell 30 provided in the embodiment of the present application includes a shell 31 and an electrode assembly 32, the electrode assembly 32 is accommodated in the shell 31, the shell 31 includes a reinforcement 314 and a first wall 313, the reinforcement 314 is arranged on one side of the first wall 313 along the thickness direction M, the first wall 313 includes a first sub-section 3131 and a second sub-section 3132, the reinforcement 314 is welded to the first sub-section 3131 and the second sub-section 3132 respectively, and forms a weld 31a, and the weld 31a is arranged on the surface of the first wall 313 on the side facing away from the reinforcement 314.

[0117] The first wall 313 may be a portion of the housing 311 of the shell 31. Optionally, the shell 31 may have one, two, or more first walls 313. The first wall 313 may be a wall portion of the shell 31 having a larger surface area, or the first wall 313 may be a wall portion of the shell 31 having a smaller surface area. Alternatively, in an embodiment where the shell 31 includes a plurality of first walls 313, at least one first wall 313 may be a wall portion of the shell 31 having a larger surface area, and at least another first wall 313 may be a wall portion of the shell 31 having a smaller surface area.

[0118] Since the housing 31 may have one or two first walls 313 , the housing 31 may have one, two, or more welds 31 a and may have reinforcement members 314 whose number corresponds to the number of the first walls 313 .

[0119] The reinforcement 314 is welded to the first sub-section 3131 and the second sub-section 3132, respectively, to form a weld 31a. Alternatively, the first sub-section 3131 and the second sub-section 3132 can be welded to each other. For example, the first sub-section 3131 and the second sub-section 3132 are welded to the reinforcement 314 at opposite ends to form a weld 31a. Alternatively, the first sub-section 3131 and the second sub-section 3132 are welded to each other at opposite ends to form a weld 31a, and each is welded to the reinforcement 314 to form a weld 31a, forming a total of three welds 31a spaced apart from each other. Of course, the first sub-section 3131 and the second sub-section 3132 can also be arranged without welding, and their opposite ends can be in contact or spaced apart, and the first sub-section 3131 and the second sub-section 3132 can be welded to the reinforcement 314 to form two welds 31a spaced apart from each other.

[0120] The weld 31a is provided on the side of the first wall 313 facing away from the reinforcement 314. Therefore, during the welding process between the first sub-section 3131 and the reinforcement 314, or between the second sub-section 3132 and the reinforcement 314, the process can be performed from the side of the first wall 313 facing away from the reinforcement 314. The weld 31a can extend in a strip shape, or can be arranged in a dotted pattern at intervals, and the selection can be made as needed.

[0121] Optionally, the reinforcement member 314 may be disposed on a side of the first wall 313 facing away from the electrode assembly 32 , or the reinforcement member 314 may be disposed on a side of the first wall 313 facing the electrode assembly 32 .

[0122] Optionally, the material of the shell 31 can be various suitable materials. For example, the material of the shell 31 can be aluminum, steel, or titanium alloy.

[0123] The reinforcement member 314 may be in a strip shape and extend along the extending direction of the weld 31 a , or the reinforcement member 314 may be in other suitable shapes.

[0124] The material of the reinforcement 314 can be the same as or different from the material of the first wall 313. For example, the material of the reinforcement 314 is the same as the material of the first wall 313, so that the reinforcement 314 can be welded to the first sub-portion 3131 and the second sub-portion 3132 of the first wall 313 respectively.

[0125] The weld 31a is arranged on the surface of the first wall 313 on the side facing away from the reinforcement 314, and the reinforcement 314 has a reinforcing effect on the structural strength of the shell 31 at the weld 31a. When the weld 31a is subjected to tension and has a tendency to crack, the reinforcement 314 can prevent the weld 31a from cracking, which helps to reduce the risk of cracking of the weld 31a.

[0126] The battery cell 30 provided in the embodiment of the present application is beneficial to improving the structural strength of the weld 31a on the first wall 313 and reducing the risk of cracking of the shell 31 at the weld 31a by arranging the weld 31a on the surface of the first wall 313 facing away from the reinforcement 314, and arranging the first sub-section 3131 and the second sub-section 3132 to be welded to the reinforcement 314 respectively. This is beneficial to improving the reliability performance of the battery cell 30.

[0127] In some embodiments, the material of the first wall 313 includes titanium alloy or steel.

[0128] It is understood that both titanium alloy and steel have strong structural strength, such as tensile strength. In the event of thermal runaway of the battery cell 30, the temperature of the battery cell 30 rises rapidly and a large amount of gas is generated, exerting a large tensile force on the outer shell 31. Since the first wall 313 has strong tensile strength, the deformation resistance of the first wall 313 is improved in the event of thermal runaway of the battery cell 30.

[0129] Therefore, by setting the material of the first wall 313 to include titanium alloy or steel, it is beneficial to improve the structural strength of the shell 311 and reduce the risk of damage to the outer shell 31. Especially in the case of thermal runaway of the battery cell 30, the first wall 313 has a strong tensile strength, which is beneficial to reduce the risk of damage to the first wall 313, and further reduce the risk of further spread of thermal runaway of the battery cell 30, which is beneficial to further improve the reliability performance of the battery cell 30.

[0130] In some embodiments, as Figure 6 and Figure 7 As shown, the thickness e of the first wall 313 satisfies: 0.075≤e≤0.4 mm.

[0131] Alternatively, e may be 0.075, 0.08, 0.09, 0.1, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.2, 0.22, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.3, 0.32, 0.34, 0.35, 0.36, 0.38 or 0.4, etc.

[0132] It can be understood that, to a certain extent, the greater the thickness e of the first wall 313, the more conducive it is to improving the structural strength of the first wall 313, and the smaller the thickness e of the first wall 313 to a certain extent, the easier it is to weld the first sub-section 3131 and the second sub-section 3132 of the first wall 313 to the reinforcement 314 respectively.

[0133] After systematic analysis and long-term practice, the inventors found that setting 0.075≤e≤0.4mm is beneficial to improving the structural strength of the first wall 313 while reducing the difficulty of welding the first sub-section 3131 and the second sub-section 3132 to the reinforcement 314 respectively.

[0134] In some embodiments, 0.15≤e≤0.3 mm.

[0135] Optionally, e can be 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29 or 0.3, etc.

[0136] After further systematic analysis and long-term practice, the inventors found that setting 0.15≤e≤0.3mm is beneficial to further improve the structural strength of the first wall 313 and further reduce the process difficulty of welding the first sub-section 3131 and the second sub-section 3132 to the reinforcement 314 respectively.

[0137] In some embodiments, the electrode assembly 32 includes a positive electrode sheet, which includes a positive electrode active material capable of reversibly extracting and inserting metal ions, and the positive electrode active material includes a nickel-containing compound.

[0138] Providing a positive electrode active material that includes a nickel compound is beneficial for increasing the energy density of the battery cell 30 and improving the cycle life of the battery cell 30, but it also increases the gas generated by the battery cell 30 during cycling. In particular, in the event of thermal runaway of the battery cell 30, the large amount of gas inside the battery cell 30 will exert a significant force on the first wall 313 of the outer shell 31, causing a high risk of deformation of the outer shell 31. This application, by providing a reinforcement 314 to increase the structural strength of the weld 31a of the first wall 313, helps reduce the risk of cracking in the weld 31a in the event of thermal runaway of the battery cell 30, thereby reducing the risk of further spread of thermal runaway in the battery cell 30.

[0139] Therefore, providing the positive electrode active material with a nickel element compound portion is beneficial to improving the energy density of the battery cell 30 and improving the cycle life of the battery cell 30. By providing the reinforcement 314, it is beneficial to improve the structural strength of the weld 31a of the first wall 313. In the event of thermal runaway of the battery cell 30, it is beneficial to reduce the risk of cracking of the weld 31a, and further help reduce the risk of further spread of thermal runaway of the battery cell 30, so as to improve the reliability performance of the battery cell 30.

[0140] In some embodiments, the electrode assembly 32 further includes a negative electrode plate, which includes a negative electrode active material capable of reversibly extracting and inserting metal ions, and the negative electrode active material includes a silicon-based material.

[0141] Since silicon-based materials can accommodate more metal ions than other elements, for example, the capacity of silicon-based materials is about ten times that of graphite, the energy density of the battery cell 30 can be effectively improved.

[0142] However, when the negative electrode active material of the negative electrode plate is silicon-based, the deformation of the electrode assembly 32 in the battery cell 30 during use increases. In particular, during the charging process of the battery cell 30, metal ions are embedded in the silicon-based material of the negative electrode plate, causing the electrode assembly 32 to expand in volume, thereby increasing the pressure of the electrode assembly 32 on the outer shell 31 of the battery cell 30 and increasing the force on the weld 31a of the first wall 313. However, the present application provides a reinforcement member 314, and arranges the first sub-section 3131 and the second sub-section 3132 to be connected to the reinforcement member 314, which helps reduce the risk of cracking in the weld 31a.

[0143] Therefore, setting the negative electrode active material to include silicon-based materials is beneficial to improving the energy density of the battery cell 30. By setting the first sub-section 3131 and the second sub-section 3132 to be welded to the reinforcement 314 respectively, it is beneficial to reduce the risk of cracking of the weld 31a, thereby reducing the risk of further spread of thermal runaway of the battery cell 30, and improving the reliability performance of the battery cell 30.

[0144] In some embodiments, the reinforcement 314 and the first wall 313 are both made of titanium alloy.

[0145] It can be understood that titanium alloy has strong structural strength, which is beneficial to improving the structural strength of the first wall 313. When the positive electrode active material of the battery cell 30 includes a nickel-containing compound and the negative electrode active material includes a silicon-based material, it is beneficial to reduce the risk of deformation of the first wall 313, thereby reducing the risk of further spread of thermal runaway of the battery cell 30.

[0146] In addition, since the materials of the reinforcement 314 and the first wall 313 both include titanium alloy, it is easier to weld the reinforcement 314 to the first sub-section 3131 and the second sub-section 3132 respectively, and it is beneficial to improve the strength of the welding connection between the reinforcement 314 and the first sub-section 3131 and the second sub-section 3132 respectively.

[0147] Therefore, the materials used to set the first wall 313 and the reinforcement 314 include titanium alloy, which is beneficial to improving the structural strength of the first wall 313, reducing the risk of further spread of thermal runaway of the battery cell 30, and improving the strength of the welding connection between the reinforcement 314 and the first sub-section 3131 and the second sub-section 3132, respectively, and facilitating the smooth progress of the welding process.

[0148] In some embodiments, the reinforcement 314 and the first wall 313 are both made of steel.

[0149] Since the materials of the reinforcement 314 and the first wall 313 both include titanium alloy, steel also has a relatively high structural strength. By setting the materials of the first wall 313 and the reinforcement 314 both to include steel, it is beneficial to improve the structural strength of the first wall 313, reduce the risk of further spread of thermal runaway of the battery cell 30, and help to improve the strength of the welding connection between the reinforcement 314 and the first sub-section 3131 and the second sub-section 3132, respectively, and facilitate the smooth progress of the welding process.

[0150] In some embodiments, as Figure 7 and Figure 8 As shown, the thickness d of the reinforcement 314 satisfies: 0.2 mm ≤ d ≤ 1 mm.

[0151] Optionally, d may be 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm or 1 mm, etc.

[0152] It can be understood that, to a certain extent, the greater the thickness d of the reinforcement 314 is, the more conducive it is to reducing the risk of welding through between the first sub-section 3131 and the reinforcement 314 or the second sub-section 3132 and the reinforcement 314, so as to improve the product yield of the shell 31, and the smaller the thickness d of the reinforcement 314 is to a certain extent, the more conducive it is to reducing the space occupied by the reinforcement 314, so as to improve the energy density of the battery cell 30.

[0153] Therefore, after systematic analysis and long-term practice, the inventors found that setting 0.2mm≤d≤1mm is beneficial to reducing the space occupied by the reinforcement 314, so as to improve the energy density of the battery cell 30, and is beneficial to reducing the risk of welding through the reinforcement 314 and the first sub-section 3131 or the reinforcement 314 and the second sub-section 3132.

[0154] In some embodiments, as Figure 9 As shown, the weld 31a includes a first weld 311a and a second weld 312a. The reinforcement 314 is welded to the first sub-section 3131 to form the first weld 311a. The reinforcement 314 is welded to the second sub-section 3132 to form the second weld 312a. The first weld 311a and the second weld 312a are spaced apart.

[0155] In this way, the first weld 311a formed by welding the first sub-section 3131 to the reinforcement 314 and the second weld 312a formed by welding the second sub-section 3132 to the reinforcement 314 are spaced apart, and the first sub-section 3131 and the second sub-section 3132 are respectively welded to the reinforcement 314, which is beneficial to reducing the risk of the reinforcement 314 being welded through, and is beneficial to reducing the size of the first weld 311a and the second weld 312a formed after welding and the protruding distance in the direction away from the reinforcement 314, so as to reduce the risk of the weld 31a damaging other structural parts.

[0156] In some embodiments, as Figure 7 and Figure 8 As shown, the reinforcement 314, the first sub-portion 3131 and the second sub-portion 3132 are welded together to form a weld 31 a.

[0157] In this way, the reinforcement 314 is welded to the first sub-portion 3131 and the second sub-portion 3132 respectively, and the first sub-portion 3131 and the second sub-portion 3132 are welded to each other, which is beneficial to improving the welding strength between the reinforcement 314 and the first wall 313 .

[0158] Specifically, during the welding process, welding is performed at the junction of the first sub-section 3131, the second sub-section 3132, and the reinforcement 314 to form a weld 31a. The first sub-section 3131, the second sub-section 3132, and the reinforcement 314 are then welded together. The first sub-section 3131, the second sub-section 3132, and the reinforcement 314 are connected by the same weld 31a. This simplifies the welding process of the first sub-section 3131, the second sub-section 3132, and the reinforcement 314.

[0159] Therefore, welding the reinforcement 314, the first sub-section 3131 and the second sub-section 3132 is advantageous in further improving the welding strength between the reinforcement 314 and the first wall 313, further reducing the risk of cracking of the weld 31a of the first wall 313, and simplifying the welding process of the first sub-section 3131, the second sub-section 3132 and the reinforcement 314.

[0160] Optionally, the first wall 313 may be disposed opposite to a side surface of the electrode assembly 32 having a larger area, or the first wall 313 may be disposed opposite to a side surface of the electrode assembly 32 having a smaller area, and the arrangement may be made according to actual needs.

[0161] In some embodiments, as Figure 4 、 Figure 6 and Figure 7 As shown, the electrode assembly 32 includes an electrode body 321 and an electrode tab 322. The electrode tab 322 extends from the end of the electrode body 321 along the first direction X. The electrode body 321 includes two first surfaces 321a that are opposite each other along the first direction X and two second surfaces 321b that are opposite each other along the third direction Z. The first surface 321a connects the two second surfaces 321b. The first direction X, the second direction Y, and the third direction Z are perpendicular to each other. The area of ​​the first surface 321a is larger than the area of ​​the second surface 321b. The first wall 313 is disposed opposite the second surface 321b.

[0162] The first surface 321a of the electrode body 321 is larger than the second surface 321b. When the electrode assembly 32 expands, the expansion amount of the electrode assembly 32 along the second direction Y is greater than the expansion amount along the third direction Z. Since the first wall 313 and the second surface 321b are arranged opposite to each other, the expansion force of the electrode assembly 32 on the first wall 313 is smaller, which is beneficial to reducing the risk of cracking of the weld 31a of the first wall 313.

[0163] Therefore, arranging the first wall 313 and the second surface 321b opposite to each other is beneficial to reducing the expansion force on the first wall 313 when the electrode assembly 32 expands, and further helps to reduce the risk of cracking of the weld 31a.

[0164] In some embodiments, as Figure 7 and Figure 8As shown, the electrode assembly 32 is in a wound shape, and the second surface 321b is in an arc shape that bulges toward the first wall 313. The battery cell 30 includes at least two electrode assemblies 32, and the at least two electrode assemblies 32 are arranged along the second direction Y. The first wall 313 and the two second surfaces 321b of two adjacent electrode assemblies 32 along the second direction Y enclose a virtual space S, and the reinforcement member 314 is disposed within the virtual space S.

[0165] The second surface 321b is arc-shaped and protrudes toward the first wall 313. A virtual space S is formed between two adjacent second surfaces 321b and the first wall 313 along the second direction Y. This virtual space S may not be closed. Alternatively, the second surface 321b may abut against the first wall 313, and the resulting virtual space S may be circumferentially closed or open. The second surface 321b may be spaced apart from the first wall 313, and the virtual space S formed by two adjacent second surfaces 321b and the first wall 313 may be circumferentially open.

[0166] The virtual space S cannot be used by the electrode assembly 32 . By arranging the reinforcement 314 in the virtual space S, the space inside the battery cell 30 additionally occupied by the reinforcement 314 can be reduced, thereby improving the battery energy density.

[0167] In some embodiments, as Figure 6 、 Figure 7 and Figure 8 As shown, the housing 31 includes two first walls 313 , and the two first walls 313 are arranged opposite to each other along the thickness direction M.

[0168] In this way, the shell 31 can be completed by splicing two "U"-shaped groove structures and welding them together on the two first walls 313. The "U"-shaped groove structure only needs to undergo two simple bends, which is conducive to simplifying the processing technology of the shell 31 of the battery cell 30.

[0169] In some embodiments, as Figure 6 and Figure 7 As shown, the reinforcement member 314 is disposed on a side of the first wall 313 facing the electrode assembly 32 .

[0170] In this way, the reinforcement member 314 is disposed inside the outer shell 31. The welding process between the first wall 313 and the reinforcement member 314 can be performed from outside the outer shell 31, facilitating the welding of the first subsection 3131 and the second subsection 3132 to the reinforcement member 314. Furthermore, the reinforcement member 314 being disposed inside the outer shell 31 helps reduce the risk of scratching other structures outside the battery cell 30 by the reinforcement member 314.

[0171] In some embodiments, as Figure 10 、 Figure 11and Figure 12 As shown, the housing 31 includes a second wall 315 , which intersects with the first wall 313 . The first wall 313 has an avoidance groove 315 a , and a portion of the reinforcement 314 is disposed in the avoidance groove 315 a .

[0172] The second wall 315 intersects with the first wall 313 . Optionally, the first wall 313 may be a portion of the housing 311 , and the second wall 315 may be at least a portion of the end cover 312 .

[0173] The second wall 315 is provided with an avoidance groove 315a, and a part of the reinforcement 314 is provided in the avoidance groove 315a. Therefore, at the end of the reinforcement 314 facing the second wall 315, there is no need to reserve additional space for the reinforcement 314, which is beneficial to improving the energy density of the battery cell 30. The cooperation between the avoidance groove 315a and the reinforcement 314 can provide a certain positioning effect for the second wall 315, facilitate the assembly of the second wall 315 and the first wall 313, and help simplify the assembly process of the battery cell 30.

[0174] Second, as Figure 5 As shown, the shell 31 provided in the embodiment of the present application includes a first wall 313 and a reinforcement 314, the first wall 313 includes a first sub-section 3131 and a second sub-section 3132, the reinforcement 314 is arranged on one side of the first wall 313 along the thickness direction M, the reinforcement 314 is welded to the first sub-section 3131 and the second sub-section 3132 respectively, and forms a weld 31a, and the weld 31a is arranged on the side of the first wall 313 facing away from the reinforcement 314.

[0175] The shell 31 provided in the embodiment of the present application is welded to the reinforcement 314 respectively by setting the first sub-portion 3131 and the second sub-portion 3132 of the first wall 313 to form a weld 31a, which is beneficial to improving the structural strength of the shell 31 corresponding to the weld 31a, reducing the risk of cracking of the weld 31a of the shell 31, and improving the reliability performance of the shell 31.

[0176] In a third aspect, the battery device 10 provided in an embodiment of the present application includes the battery cell 30 provided in any of the above embodiments.

[0177] The battery device 10 provided in the embodiment of the present application has the same technical effects as the battery cell 30 provided in any of the above embodiments, and thus will not be described in detail here.

[0178] In a fourth aspect, the electrical device provided in the embodiment of the present application includes the battery device 10 provided in the above embodiment, and the battery device 10 is used to provide electrical energy.

[0179] The electric device provided in the embodiment of the present application has the same technical effects as the battery device 10 provided in the above embodiment, and thus will not be described in detail here.

[0180] In some embodiments, as Figures 4 to 12 As shown, the battery cell 30 provided in the embodiment of the present application includes a housing 31 and an electrode assembly 32, which is housed within the housing 31. The housing 31 includes a first wall 313, a second wall 315, and a reinforcement 314. The first wall 313 includes a first sub-portion 3131 and a second sub-portion 3132. The reinforcement 314, the first sub-portion 3131, and the second sub-portion 3132 are welded together to form a weld 31a. The weld 31a is located on the side of the first wall 313 facing away from the reinforcement 314. The electrode assembly 32 is wound and includes an electrode body 321 and a tab 322. The tab 322 extends from the end of the electrode body 321 along a first direction X. The electrode body 321 includes two first surfaces 321a that oppose each other along a second direction Y and two second surfaces 321b that oppose each other along a third direction Z. The first surface 321a connects the two second surfaces 321b. The first direction X, the second direction Y, and the third direction Z are perpendicular to each other. The area of ​​the first surface 321a is greater than that of the second surface 321b, and the first wall 313 is arranged opposite to the second surface 321b. The second surface 321b is in an arc shape that bulges toward the first wall 313. The battery cell 30 includes at least two electrode assemblies 32, and the at least two electrode assemblies 32 are arranged along the second direction Y. The first wall 313 and the two second surfaces 321b of two adjacent electrode assemblies 32 along the second direction Y enclose a virtual space S, and the reinforcement 314 is arranged in the virtual space S. The housing 31 includes two first walls 313 arranged opposite to each other along the thickness direction M. The material of the first wall 313 includes titanium alloy or steel, and the thickness e of the first wall 313 satisfies: 0.075≤e≤0.4mm. The electrode assembly 32 includes a positive electrode plate and a negative electrode plate. The positive electrode plate includes a positive electrode active material that can reversibly extract and insert metal ions, and the positive electrode active material includes a nickel-containing compound. The negative electrode plate includes a negative electrode active material capable of reversibly extracting and inserting metal ions. The negative electrode active material comprises a silicon-based material. The reinforcement 314 and first wall 313 are both made of titanium alloy or steel. The thickness d of the reinforcement 314 satisfies the following conditions: 0.2 mm ≤ d ≤ 1 mm. The second wall 315 intersects the first wall 313. The first wall 313 has an escape groove 315 a. A portion of the reinforcement 314 is disposed within the escape groove 315 a.

[0181] The battery cell 30 provided in the embodiment of the present application is beneficial to improving the structural strength of the weld 31a on the outer shell 31 and reducing the risk of cracking of the outer shell 31 at the weld 31a, thereby improving the reliability performance of the battery cell 30.

[0182] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and components may be substituted with equivalents without departing from the scope of the present application. In particular, the various technical features described 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 encompasses all technical solutions within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: The housing comprises a reinforcement member and a first wall, the reinforcement member being provided on one side of the first wall in a thickness direction, the first wall comprising a first sub-portion and a second sub-portion, the reinforcement member being welded to the first sub-portion and the second sub-portion, respectively, to form a weld, the weld being provided on a surface of the first wall facing away from the reinforcement member; The electrode assembly is accommodated in the shell.

2. The battery cell according to claim 1, wherein: The first wall is made of titanium alloy or steel.

3. The battery cell according to claim 2, characterized in that: The thickness e of the first wall satisfies: 0.075≤e≤0.4 mm.

4. The battery cell according to claim 3, characterized in that 0.15≤e≤0.3mm.

5. The battery cell according to claim 1, characterized in that The electrode assembly includes a positive electrode plate, the positive electrode plate includes a positive electrode active material capable of reversibly extracting and inserting metal ions, and the positive electrode active material includes a nickel-containing compound.

6. The battery cell according to claim 1, characterized in that The electrode assembly further includes a negative electrode plate, wherein the negative electrode plate includes a negative electrode active material capable of reversibly extracting and inserting metal ions, and the negative electrode active material includes a silicon-based material.

7. The battery cell according to claim 1, characterized in that The materials of the reinforcement and the first wall both include titanium alloy, or the materials of the reinforcement and the first wall both include steel.

8. The battery cell according to claim 1, wherein: The thickness d of the reinforcement satisfies: 0.2 mm ≤ d ≤ 1 mm.

9. The battery cell according to claim 1, characterized in that The weld includes a first weld and a second weld. The reinforcement is welded to the first sub-section to form the first weld. The reinforcement is welded to the second sub-section to form the second weld. The first weld and the second weld are spaced apart.

10. The battery cell according to claim 1, characterized in that The reinforcement, the first sub-portion and the second sub-portion are connected by welding to form a weld.

11. The battery cell according to any one of claims 1 to 10, characterized in that: The electrode assembly includes an electrode body and a tab, wherein the tab is extended from an end of the electrode body along a first direction, the electrode body includes two first surfaces opposite to each other along a second direction and two second surfaces opposite to each other along a third direction, the first surface connects the two second surfaces, and the first direction, the second direction, and the third direction are perpendicular to each other; The area of ​​the first surface is greater than that of the second surface, and the first wall is arranged opposite to the second surface.

12. The battery cell according to claim 11, characterized in that The electrode assembly is in a wound shape, the second surface is in an arc shape convex toward the first wall, the battery cell includes at least two electrode assemblies, and the at least two electrode assemblies are arranged along the second direction; The first wall and the two second surfaces of the two electrode assemblies adjacent to each other along the second direction enclose a virtual space, and the reinforcement is disposed in the virtual space.

13. The battery cell according to any one of claims 1 to 10, characterized in that: The housing includes two first walls, which are arranged opposite to each other along the thickness direction.

14. The battery cell according to any one of claims 1 to 10, characterized in that: The reinforcement is arranged on a side of the first wall facing the electrode assembly.

15. The battery cell according to any one of claims 1 to 10, characterized in that: The housing includes a second wall intersecting the first wall. The first wall has an avoidance groove, and a portion of the reinforcement is disposed in the avoidance groove.

16. A housing, characterized in that: include: a first wall comprising a first subsection and a second subsection; A reinforcement is provided on one side of the first wall along the thickness direction. The reinforcement is respectively welded to the first sub-portion and the second sub-portion to form a weld. The weld is provided on the side of the first wall facing away from the reinforcement.

17. A battery device, characterized in that: The battery cell comprises the battery cell according to any one of claims 1 to 15.

18. An electrical device, characterized in that: The battery device according to claim 17 is included, and is used to provide electrical energy.

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