Battery monomer, battery and electric equipment

Abstract

The embodiment of the invention provides a battery monomer, a battery and electric equipment. The battery monomer comprises a shell and a first insulating part, the shell is provided with a welding printing area, the first insulating part is arranged on the outer surface of the shell, the first insulating part is provided with a first thickening area, and the first thickening area covers at least one part of the welding printing area. Therefore, the risk of insulation failure of the battery monomer due to the fact that the first insulating part is punctured by the welding printing area is reduced, and the insulating property of the battery monomer is improved.

Description

Battery cells, batteries and electrical equipment Technical Field

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

[0002] With the development of new energy technology, batteries are used more and more widely, for example, in mobile phones, laptops, electric vehicles, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes and power tools.

[0003] In battery technology, battery cells must have good insulation properties to reduce the risk of short circuits, fires, explosions, and other issues. Therefore, improving the insulation performance of battery cells is a pressing issue in battery technology.

[0004] Summary of the Invention

[0005] The embodiments of the present application provide a battery cell, a battery, and an electrical device, which can effectively improve the insulation performance of the battery cell.

[0006] In a first aspect, embodiments of the present application provide a battery cell comprising a housing and a first insulating member. The housing has a weld print region. The first insulating member is disposed on an outer surface of the housing and has a first thickened region that covers at least a portion of the weld print region.

[0007] In the above technical solution, the first thickened area of ​​the first insulating member covers at least a portion of the weld mark area, reducing the risk of the weld mark area puncturing the first insulating member and causing insulation failure of the battery cell, thereby improving the insulation performance of the battery cell.

[0008] In some embodiments, the first insulating member includes a first insulating portion and a second insulating portion, the first insulating portion and the second insulating portion being disposed on the outer surface of the housing, the first insulating portion and the second insulating portion having a first overlapping region, the first overlapping region forming a first thickened region. The first insulating portion and the second insulating portion overlap to form the first overlapping region, thereby locally thickening the first insulating member to form the first thickened region. The first thickened region is formed in a simple manner.

[0009] In some embodiments, the first insulating member is wrapped around the outer surface of the shell along the circumference of the shell, and the two ends of the first insulating member along the circumference of the shell respectively form a first insulating portion and a second insulating portion. The first insulating member is wrapped around the outer surface of the shell along the circumference of the shell, which can quickly cover more areas of the outer surface of the shell, thereby improving the insulation performance of the battery cell. The first insulating member is wrapped around the outer surface of the shell along the circumference of the shell, and the two ends of the first insulating member overlap with each other to form a first thickened area. The molding method of the first thickened area is simple. When the first insulating member is wrapped around the outer surface of the shell, the position of the weld print area can be more conveniently confirmed, and the first thickened area can quickly cover the weld print area, thereby improving production efficiency.

[0010] In some embodiments, the housing includes a first wall portion, the weld mark area is located on the first wall portion, and the first insulating portion and the second insulating portion jointly cover the outer surface of the first wall portion. The first insulating portion and the second insulating portion jointly cover the outer surface of the first wall portion having the weld mark area, thereby insulating the first wall portion and thereby improving the insulation performance of the battery cell.

[0011] In some embodiments, the first thickened area completely covers the weld print area, thereby increasing the overlap between the first thickened area and the weld print area and further reducing the risk of the weld print area puncturing the first insulating member.

[0012] In some embodiments, along the circumference of the shell, the width of the first thickened area is W1, the width of the weld print area is W2, and W1>W2. In this way, the first thickened area has more area to cover the weld print area.

[0013] In some embodiments, W1-W2≥1 mm. Thus, the first thickened area has a larger coverage margin, which is conducive to achieving complete coverage of the weld print area by the first thickened area, meeting the alignment accuracy requirements between the first thickened area and the weld print area, and improving the assembly efficiency of the first insulating member and the housing.

[0014] In some embodiments, W1 is greater than or equal to 3 mm. In this way, the first thickened area has a larger width and can cover more areas of the weld print area.

[0015] In some embodiments, the weld mark area includes a first protrusion protruding from the outer surface of the housing. The height of the first protrusion protruding from the outer surface of the housing is H1, and the thickness of the first thickened area is D1, where H1 < D1. In this way, even if the first protrusion completely penetrates the first thickened area, it is difficult to puncture the first thickened area, further reducing the risk of insulation failure of the battery cell.

[0016] In some embodiments, the housing is formed by bending a sheet material. The sheet material includes a first end and a second end along the circumference of the housing. The first and second ends are welded together to form a weld mark. This simple molding method for the housing effectively reduces the difficulty of forming the housing. Furthermore, when forming the housing, only the first and second ends of the sheet material need to be welded, and the weld mark is formed in the welded area between the first and second ends, thereby providing the housing with excellent strength.

[0017] In some embodiments, the end surface of the first end portion and the end surface of the second end portion are welded together. This eliminates any overlap between the two ends of the plate, saving material and reducing the production cost of the housing. Furthermore, this makes the housing smoother, increases the internal space of the housing, and contributes to increasing the energy density of the battery cell.

[0018] In some embodiments, the first end portion and the second end portion have a second overlapping region, and the weld mark region is located in the second overlapping region. This can reduce the difficulty of welding the first end portion and the second end portion, increase the contact area between the first end portion and the second end portion, and improve the connection strength between the first end portion and the second end portion.

[0019] In some embodiments, the housing includes multiple walls and multiple corners. Each corner connects two adjacent walls along the circumference of the housing. The weld imprint is located on the wall. This reduces the difficulty of positioning the housing during the welding process, thereby reducing the difficulty of forming the housing. Furthermore, the placement of the weld imprint on the wall, rather than the corners, enhances the connection strength of the housing at the welding location, thereby increasing the strength of the housing.

[0020] In some embodiments, the multiple walls include a first wall and a second wall, the first wall and the second wall being connected by a corner portion. The second wall is the wall portion with the largest outer surface area in the housing, and the weld mark area is located in the first wall. Because the second wall portion has the largest outer surface area in the housing, when the electrode assembly inside the battery cell expands, the second wall portion is more susceptible to deformation than the first wall portion. Positioning the weld mark area in the first wall portion, which has a smaller deformation, can, on the one hand, reduce the risk of damage to the housing in the weld mark area when the electrode assembly expands, and, on the other hand, reduce the risk of the weld mark area puncturing the first insulating member when the electrode assembly expands.

[0021] In some embodiments, the plurality of walls include two first walls and two second walls, the two first walls being arranged opposite each other along a first direction, and the two second walls being arranged opposite each other along a second direction, with the first direction being perpendicular to the second direction. At least one of the first walls has a weld mark formed therein. This housing has a quadrangular prism structure and is simple in structure.

[0022] In some embodiments, the battery cell further includes a pressure relief mechanism, with the pressure relief mechanism and the weld mark area located on two separate walls. By not locating the pressure relief mechanism and the weld mark area on the same wall, the impact of the weld mark area on the pressure relief mechanism during the shell welding process is reduced, thereby improving the reliability of the pressure relief mechanism.

[0023] In some embodiments, the plurality of walls include two opposing first walls, with the pressure relief mechanism and the weld mark area located on the two first walls, respectively. This allows the pressure relief mechanism and the weld mark area to be further apart in the circumferential direction of the housing, further reducing the impact of the weld mark area on the pressure relief mechanism during the process of welding the housing.

[0024] In some embodiments, the battery cell further includes an electrode assembly and a second insulating member. The electrode assembly is disposed within the shell. The second insulating member is disposed between the electrode assembly and the shell, and the second insulating member is configured to insulate and isolate the electrode assembly and the shell. The second insulating member has a second thickened area, and the second thickened area covers at least a portion of the weld print area. The second insulating member is located between the electrode assembly and the shell, and serves to separate the electrode assembly and the shell to achieve insulation between the electrode assembly and the shell. The second thickened area of ​​the second insulating member covers at least a portion of the weld print area, which can reduce the risk of the weld print area puncturing the second insulating member, thereby causing insulation failure between the electrode assembly and the shell.

[0025] In some embodiments, the second insulating member includes a third insulating portion and a fourth insulating portion, the third insulating portion and the fourth insulating portion having a third overlapping region, and the third overlapping region forming a second thickened region. The third overlapping region is formed by overlapping the third insulating portion and the fourth insulating portion to locally thicken the second insulating member, thereby correspondingly forming the second thickened region. The second thickened region is formed in a simple direction.

[0026] In some embodiments, the second insulating member is wrapped around the outer surface of the electrode assembly along the circumference of the shell, and the two ends of the second insulating member along the circumference of the shell respectively form a third insulating portion and a fourth insulating portion. The second insulating member is wrapped around the outer surface of the electrode assembly along the circumference of the shell, which can quickly cover more areas of the outer surface of the electrode assembly, thereby improving the insulation performance between the electrode assembly and the shell. The second insulating member is wrapped around the outer surface of the electrode assembly along the circumference of the shell, and the two ends of the second insulating member overlap each other, thereby forming a second thickened region, and the second thickened region is simple to form.

[0027] In some embodiments, the second thickened area completely covers the weld print area, thereby increasing the overlap area between the second thickened area and the weld print area and further reducing the risk of the weld print area puncturing the second insulating member.

[0028] In some embodiments, the weld print area includes a second protrusion protruding from the inner surface of the housing. The second protrusion protrudes from the inner surface of the housing by a height H2. The second thickened area has a thickness D2, where H2 < D2. Thus, even if the second protrusion completely penetrates the second thickened area, it is difficult to puncture the second thickened area, further reducing the risk of insulation failure between the electrode assembly and the housing.

[0029] In some embodiments, the housing is a rectangular parallelepiped housing, which is suitable for rectangular parallelepiped battery cells and can meet the large capacity requirements of the battery cells.

[0030] In some embodiments, the housing has openings at opposite ends along its length. The length of the housing is a, the width is b, and the height is c, where b ≤ c ≤ a / 1.5. The elongated shape of the housing helps increase the energy density of the battery cells.

[0031] In some embodiments, the housing has openings at opposite ends. The battery cell also includes end caps that correspond to the openings and seal the openings. During assembly of the battery cell, the electrode assembly can be inserted into the housing through the openings at either end of the housing, effectively improving battery cell assembly efficiency.

[0032] In a second aspect, an embodiment of the present application provides a battery, comprising a battery cell provided by any embodiment of the first aspect.

[0033] In a third aspect, an embodiment of the present application provides an electrical device, comprising a battery cell provided by any one embodiment of the first aspect, wherein the battery cell is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0035] FIG2 is an exploded view of a battery provided in some embodiments of the present application;

[0036] FIG3 is an axonometric view of a battery cell provided in some embodiments of the present application;

[0037] FIG4 is an exploded view of the battery cell shown in FIG3 ;

[0038] FIG5 is a partial cross-sectional view of the battery cell shown in FIG3 ;

[0039] FIG6 is an exploded view of a housing and a first insulating member according to some embodiments of the present application;

[0040] FIG7 is an assembly diagram of the housing and the first insulating member shown in FIG6 ;

[0041] FIG8 is a partial enlarged view of point A in FIG7;

[0042] FIG9 is a partial view of the housing shown in FIG8;

[0043] FIG10 is a partial enlarged view of point B in FIG8 ;

[0044] FIG11 is a schematic structural diagram of a housing provided in some embodiments of the present application;

[0045] FIG12 is a schematic structural diagram of the housing shown in FIG11 after it is unfolded;

[0046] FIG13 is a schematic structural diagram of the housing shown in FIG11 after removing the weld mark area;

[0047] FIG14 is a schematic structural diagram of a housing provided in some other embodiments of the present application;

[0048] FIG15 is a partial enlarged view of point C in FIG14;

[0049] FIG16 is an assembly diagram of a housing and a first insulating member provided in some other embodiments of the present application;

[0050] FIG17 is a schematic structural diagram of the housing shown in FIG16 ;

[0051] FIG18 is an axonometric view of a housing provided in some embodiments of the present application;

[0052] FIG19 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0053] FIG20 is a partial enlarged view of point D in FIG19;

[0054] FIG21 is a partial enlarged view of point E in FIG20 ;

[0055] FIG22 is an axonometric view of a shell provided in some other embodiments of the present application.

[0056] Icons: 1-housing; 11-shell; 111-weld stamping area; 1111-first convex portion; 1112-second convex portion; 112-wall portion; 1121-first wall portion; 11211-first end portion; 11212-second end portion; 11213-first end surface; 11214-second end surface; 11215-second overlapping area; 1122-second wall portion; 113-corner portion; 12-end cap; 2-electrode assembly; 21-ear; 3-first insulating member ;31-first thickened area;32-first insulating part;33-second insulating part;4-second insulating member;41-second thickened area;42-third insulating part;43-fourth insulating part;5-electrode terminal;6-pressure relief mechanism;10-battery cell;20-housing;201-first part;202-second part;100-battery;200-controller;300-motor;1000-vehicle;X-first direction;Y-second direction;Z-third direction. DETAILED DESCRIPTION

[0057] 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 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.

[0058] 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 for the purpose of describing specific embodiments only 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0063] The term "plurality" used in this application refers to two or more (including two).

[0064] 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.

[0065] The battery cells can be 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, etc., which are not limited in the embodiments of the present application.

[0066] 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, placed between the positive and negative electrodes, prevents short circuits between the positive and negative electrodes while allowing the active ions to pass through.

[0067] 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.

[0068] 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.

[0069] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. 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.).

[0070] 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 traditional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates may include but are not limited to at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides may include but are not limited to lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2) and at least one of its modified compounds, etc.

[0071] In some embodiments, a positive electrode may be a metal foam. The metal foam may be nickel foam, copper foam, aluminum foam, alloy foam, or carbon foam, among others. When a metal foam is used as the positive electrode, the surface of the metal foam may or may not be provided with a positive electrode active material. For example, a lithium source material, potassium metal, or sodium metal may be filled and / or deposited within the metal foam, where the lithium source material is lithium metal and / or a lithium-rich material.

[0072] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0073] As an example, the negative electrode current collector can be a metal foil, a metal foam, or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium can be used. The metal foam can be nickel foam, copper foam, aluminum foam, alloy foam, or carbon foam. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper 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.).

[0074] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0075] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is provided on either or both of the two facing surfaces of the negative electrode current collector.

[0076] 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 batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0077] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0078] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0079] 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 and mechanical stability can be selected.

[0080] 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.

[0081] 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.

[0082] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not specifically limit the type of electrolyte, and the electrolyte can be selected based on needs. The electrolyte can be liquid, gel, or solid.

[0083] The liquid electrolyte includes an electrolyte salt and a solvent.

[0084] In some embodiments, the electrolyte salt may be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalatoborate, lithium dioxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0085] In some embodiments, the solvent can be selected from at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, cyclopentane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent can also be an ether solvent. Ether solvents can include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether and crown ether.

[0086] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0087] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0088] As an example, the polymer solid electrolyte may be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, a single ion polymer, polyionic liquid-lithium salt, cellulose, or the like.

[0089] As an example, the inorganic solid electrolyte can be an oxide solid electrolyte (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superion conductor (lithium germanium phosphosulfide, silver germanium sulfide), amorphous sulfide) and one or more of a halide solid electrolyte, a nitride solid electrolyte and a hydride solid electrolyte.

[0090] As an example, a composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0091] 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.

[0092] In some embodiments, the electrode assembly is a laminate structure.

[0093] As an example, multiple positive electrode sheets and multiple negative electrode sheets can be provided respectively, and the multiple positive electrode sheets and the multiple negative electrode sheets can be alternately stacked.

[0094] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet may be folded to form a plurality of stacked folded segments, with a positive electrode sheet being sandwiched between adjacent folded segments.

[0095] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of stacked folded segments.

[0096] As an example, a plurality of separators may be provided, each of which is disposed between any adjacent positive electrode sheets or negative electrode sheets.

[0097] As an example, the separator may be provided continuously, and may be provided between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0098] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0099] In some embodiments, the electrode assembly has tabs that can conduct current from the electrode assembly. The tabs include a positive tab and a negative tab.

[0100] 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.

[0101] 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 this application.

[0102] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity.

[0103] In some embodiments, the battery may be a battery module. When there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0104] In some embodiments, the battery may be a battery pack, which includes a case and battery cells, wherein the battery cells or battery modules are housed in the case.

[0105] 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.

[0106] In some embodiments, the battery may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0107] In a battery cell, an insulating member is generally provided on the outside of the shell to achieve insulation of the battery cell, thereby reducing the risk of short circuit in the battery cell, which may cause fire or explosion of the battery cell.

[0108] As an important component of the battery cell, the shell is generally formed by stamping or stretching the base material. During the forming process, the base material is subjected to increased extrusion pressure, which makes it prone to breakage. The shell is difficult to form, especially the long, thin-walled shell.

[0109] In order to reduce the difficulty of forming the shell, the shell can be formed by welding the sheet. After the shell is formed, a weld mark area will be formed at the welding position. The weld mark area will affect the insulating parts located on the outside of the shell. The weld mark area may puncture the insulating parts, thereby causing the insulation failure of the battery cell.

[0110] In view of this, an embodiment of the present application provides a battery cell, which improves the insulation performance of the battery cell by providing a first thickened area on a first insulating member located on the outside of the shell, and covering at least a portion of the weld mark area with the first thickened area, so as to reduce the risk of the weld mark area piercing the first insulating member and causing insulation failure of the battery cell.

[0111] The battery cells described in the embodiments of the present application are suitable for batteries and electrical equipment using the battery cells.

[0112] Electrical equipment can be vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and electric tools, etc. Vehicles can be fuel vehicles, gas vehicles, or new energy vehicles. New energy vehicles can be pure electric vehicles, hybrid vehicles, or extended-range vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical equipment.

[0113] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle as an example.

[0114] Please refer to Figure 1, which is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of the present application. A battery 100 is disposed within vehicle 1000. Battery 100 can be located at the bottom, front, or rear of vehicle 1000. Battery 100 can be used to power vehicle 1000, for example, as an operating power source for vehicle 1000.

[0115] The vehicle 1000 may further include a controller 200 and a motor 300 . The controller 200 is used to control the battery 100 to supply power to the motor 300 , for example, to meet the power requirements of the vehicle 1000 during startup, navigation, and driving.

[0116] In some embodiments of the present application, the battery 100 can not only serve as the operating power source of the vehicle 1000, but also serve as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0117] Please refer to Figure 2, which is an exploded view of a battery 100 provided in some embodiments of the present application. The battery 100 includes a battery cell 10 and a housing 20, wherein the battery cell 10 is accommodated in the housing 20.

[0118] The housing 20 is a component that houses the battery cells 10 and provides a storage space for the battery cells 10. The housing 20 can have various structures. In some embodiments, the housing 20 can include a first portion 201 and a second portion 202, which overlap to define a storage space for the battery cells 10. The first portion 201 and the second portion 202 can have various shapes, such as a rectangular parallelepiped or a cylinder. The first portion 201 can be a hollow structure with one side open, and the second portion 202 can also be a hollow structure with one side open. The open side of the second portion 202 overlaps the open side of the first portion 201, forming the housing 20 with a storage space. Alternatively, the first portion 201 can be a hollow structure with one side open, and the second portion 202 can be a plate-like structure. The second portion 202 overlaps the open side of the first portion 201, forming the housing 20 with a storage space. The first portion 201 and the second portion 202 can be sealed by a sealing element, which can be a sealing ring, sealant, etc.

[0119] In the battery 100, there can be one or more battery cells 10. If there are multiple battery cells 10, the multiple battery cells 10 can be connected in series, parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 10. Multiple battery cells 10 can be connected in series, parallel, or in a hybrid connection to form a battery module, which can then be connected in series, parallel, or in a hybrid connection to form a single unit and housed within the housing 20. Alternatively, all battery cells 10 can be directly connected in series, parallel, or in a hybrid connection, and then the entire unit formed by all battery cells 10 can be housed within the housing 20.

[0120] Referring to Figures 3-5 , Figure 3 is an isometric view of a battery cell 10 according to some embodiments of the present application; Figure 4 is an exploded view of the battery cell 10 shown in Figure 3 ; and Figure 5 is a partial cross-sectional view of the battery cell 10 shown in Figure 3 . The battery cell 10 may include a housing 1 , an electrode assembly 2 , a first insulating member 3 , and a second insulating member 4 .

[0121] The housing 1 is a component for accommodating the electrode assembly 2 and electrolyte, etc. As an example, the housing 1 may include a shell 11 and an end cap 12 .

[0122] The housing 11 may be a hollow structure with an opening at one end, or may be a hollow structure with openings at opposite ends. The housing 11 may have various shapes, such as a cylinder or a rectangular parallelepiped. The housing 11 may be made of various materials, such as copper, iron, aluminum, steel, and aluminum alloys.

[0123] The end cap 12 is a component that closes the opening of the shell 11 to isolate the internal environment of the battery cell 10 from the external environment. The end cap 12 and the shell 11 together define a storage space for accommodating the electrode assembly 2, electrolyte and other components. The end cap 12 can be connected to the shell 11 by welding or rolling to close the opening of the shell 11. The shape of the end cap 12 can be adapted to the shape of the shell 1. For example, the shell 11 is a rectangular parallelepiped structure, and the end cap 12 is a rectangular plate structure adapted to the shell 1. For another example, the shell 11 is a cylindrical structure, and the end cap 12 is a circular plate structure adapted to the shell 11. The material of the end cap 12 can also be a variety of materials, such as copper, iron, aluminum, steel, aluminum alloy, plastic, etc. The material of the end cap 12 and the shell 11 can be the same or different.

[0124] In an embodiment where the housing 11 is open at one end, one end cap 12 may be provided. In an embodiment where the housing 11 is open at two opposite ends, two end caps 12 may be provided, each of which closes the two openings of the housing 11, and the two end caps 12 and the housing 11 together define a receiving space.

[0125] The first insulating member 3 is a component disposed outside the housing 11 to achieve insulation of the battery cell 10. The first insulating member 3 is made of an insulating material, such as plastic, rubber, etc.

[0126] The second insulating member 4 is disposed inside the housing 11 to achieve insulation between the housing 11 and the electrode assembly 2. The second insulating member 4 is made of an insulating material, such as plastic, rubber, etc.

[0127] In some embodiments, the battery cell 10 may further include an electrode terminal 5, which is disposed on the outer casing 1 and is used to electrically connect to the tab 21 of the electrode assembly 2 to output electrical energy from the battery cell 10. The electrode terminal 5 may be disposed on the shell 11 of the outer casing 1 or on the end cap 12 of the outer casing 1. The electrode terminal 5 and the tab 21 may be directly connected, for example, by direct welding. The electrode terminal 5 and the tab 21 may also be indirectly connected, for example, by indirectly connecting the electrode terminal 5 and the tab 21 through a current collecting member. The current collecting member may be a metal conductor, such as copper, iron, aluminum, steel, or an aluminum alloy.

[0128] As an example, as shown in Figures 3 to 5, the shell 11 is a hollow structure with openings formed at opposite ends. End covers 12 are provided at opposite ends of the shell 11. Electrode terminals 5 are provided on the end covers 12 at both ends of the shell 11. Pole ears 21 are formed at opposite ends of the electrode assembly 2. The pole ear 21 at one end of the electrode assembly 2 is a positive pole ear, and the pole ear 21 at the other end of the electrode assembly 2 is a negative pole ear. The electrode terminal 5 on one end cover 12 is electrically connected to the positive pole ear, and the electrode terminal 5 on the other end cover 12 is electrically connected to the negative pole ear.

[0129] Please refer to Figures 6-9. Figure 6 is an exploded view of the housing 11 and the first insulating member 3 provided in some embodiments of the present application; Figure 7 is an assembly view of the housing 11 and the first insulating member 3 shown in Figure 6; Figure 8 is a partial enlarged view of point A in Figure 7; and Figure 9 is a partial view of the housing 11 shown in Figure 8. An embodiment of the present application provides a battery cell 10, comprising a housing 11 and a first insulating member 3. The housing 11 has a weld mark area 111. The first insulating member 3 is disposed on the outer surface of the housing 11 and has a first thickened area 31, which covers at least a portion of the weld mark area 111.

[0130] The shell 11 may have an opening at one end or at two opposite ends. The shell 11 may be a prism, a cylinder, etc., and the prism may be a triangular prism, a quadrangular prism, a pentagonal prism, a hexagonal prism, etc. The first insulating member 3 can achieve insulation between the battery cells 10. The first insulating member 3 can completely cover the outer surface of the shell 11, or it can cover a portion of the outer surface of the shell 11. The first insulating member 3 can be arranged on the outer surface of the shell 11 along the circumference of the shell 11, and the circumference of the shell 11 is consistent with the circumference of the opening of the shell 11.

[0131] The first insulating member 3 may be an integrally formed insulating sleeve structure; the first insulating member 3 may also be formed by a sheet surrounding the housing 11. The first insulating member 3 may be formed by connecting the end portions of a sheet together; the first insulating member 3 may also be formed by multiple sheets, with the multiple sheets being separately provided and adjacent two sheets connected to each other.

[0132] The weld mark 111 is formed by welding two parts of the housing 11 during the molding process to achieve a fixed connection between the two parts. The housing 11 may have one or more weld marks 111. For example, the housing 11 may be formed by bending a sheet of material, and the ends of the sheet of material may be welded together, forming a weld mark 111 on the housing 11. Another example is that the housing 11 may be formed by splicing multiple sheets of material, and two adjacent sheets may be welded together, forming a weld mark 111 at the weld location between the two adjacent sheets, thereby forming multiple weld marks 111 on the housing 11.

[0133] The first thickened region 31 is a locally thickened area on the first insulating member 3. The first thickened region 31 may be formed by forming a protrusion on a portion of the first insulating member 3, or by overlapping two portions of the first insulating member 3, making the overlapping region thicker.

[0134] The first thickened region 31 may correspond one-to-one with the weld imprint region 111, or one first thickened region 31 may correspond to multiple weld imprint regions 111. The first thickened region 31 covers at least a portion of the weld imprint region 111, i.e., the projection of the weld imprint region 111 along the wall thickness direction of the shell 11 is at least partially located within the first thickened region 31. The first thickened region 31 may completely cover the weld imprint region 111, i.e., the projection of the weld imprint region 111 along the wall thickness direction of the shell 11 is entirely located within the first thickened region 31; the first thickened region 31 may also cover a portion of the weld imprint region 111, i.e., a portion of the projection of the weld imprint region 111 along the wall thickness direction of the shell 11 is located within the first thickened region 31.

[0135] The weld mark area may include a first protrusion 1111 protruding from the outer surface of the housing 11. Specifically, the first protrusion 1111 is the portion of the weld mark area 111 that protrudes from the outer surface of the housing 11. The first protrusion 1111 may be solder or welding slag formed during the welding process of the housing 11. The first protrusion 1111 may also be the portion of the housing 11 that protrudes from the outer surface after the welded portion of the housing 11 is fused. The first insulating member 3 may cover at least a portion of the first protrusion 1111. Specifically, the first insulating member 3 may completely cover the first protrusion 1111 or may cover a portion of the first protrusion 1111.

[0136] In the embodiment of the present application, the first thickened area 31 of the first insulating member 3 covers at least a portion of the weld mark area 111 , reducing the risk of the weld mark area 111 puncturing the first insulating member 3 and causing insulation failure of the battery cell 10 , thereby improving the insulation performance of the battery cell 10 .

[0137] In some embodiments, please continue to refer to Figure 8. The first insulating member 3 includes a first insulating portion 32 and a second insulating portion 33. The first insulating portion 32 and the second insulating portion 33 are arranged on the outer surface of the shell 11. The first insulating portion 32 and the second insulating portion 33 have a first overlapping area, and the first overlapping area forms a first thickened area 31.

[0138] The first insulating member 3 can be formed by a single piece disposed around the housing 11, with the first insulating portion 32 and the second insulating portion 33 being two integrally formed parts of the first insulating member 3. The first insulating portion 32 and the second insulating portion 33 can also be separate and connected. For example, the first insulating member 3 can be formed by multiple separate pieces disposed around the housing 11, with adjacent pieces connected to each other. Of the two adjacent pieces, all or part of one piece forms the first insulating portion 32, and all or part of the other piece forms the second insulating portion 33. The first insulating portion 32 and the second insulating portion 33 form a first overlapping region. Of course, the first insulating member 3 can include two, three, four, or more pieces.

[0139] The overlapping portion of the first insulating portion 32 and the second insulating portion 33 is the first thickened region 31. It is understood that a portion of the first thickened region 31 is located in the first insulating portion 32, while another portion of the first thickened region 31 is located in the second insulating portion 33. Within the first thickened region 31, the first and second insulating portions 32, 33 can be connected in various ways, such as adhesive bonding or heat-seal bonding. The thickness of the first insulating portion 32 and the second insulating portion 33 can be equal or different.

[0140] The first insulating portion 32 and the second insulating portion 33 overlap to form a first overlapping region, thereby locally thickening the first insulating member 3 to form the corresponding first thickened region 31. The first thickened region 31 is formed in a simple manner. It is understood that the first insulating member 3 has two insulating layers in the first overlapping region, forming a double-layer structure. For example, in the first thickened region 31, the first insulating portion 32 is located on the side of the second insulating portion 33 facing the housing 11. Even if the weld mark 111 punctures the first insulating portion 32, it is unlikely to puncture the second insulating portion 33. The second insulating portion 33 still provides good insulation protection, thereby reducing the risk of the weld mark 111 puncturing the first insulating member 3.

[0141] In some embodiments, please continue to refer to Figures 7 and 8. The first insulating member 3 is wrapped around the outer surface of the shell 11 along the circumference of the shell 11. Along the circumference of the shell 11, the two ends of the first insulating member 3 form a first insulating portion 32 and a second insulating portion 33 respectively.

[0142] In this embodiment, the first insulating member 3 can be formed by a single piece arranged around the shell 11 along the circumference of the shell 11. The first insulating portion 32 and the second insulating portion 33 are the two end portions of the first insulating member 3. It can be understood that the two ends of the first insulating member 3 form a first overlapping area. The portion of the first insulating member 3 extending from the end surface of one end along the positive direction of the circumference of the shell 11 within the area of ​​the first preset distance L1 is one end portion of the first insulating member 3, and the length of this end portion is equal to the first preset distance L1; the portion of the first insulating member 3 extending from the end surface of the other end along the negative direction of the circumference of the shell 11 within the area of ​​the second preset distance L2 is the other end portion of the first insulating member 3, and the length of this end portion is equal to the second preset distance L2. The first preset distance L1 and the second preset distance L2 can be equal or different.

[0143] In this embodiment, the first insulating member 3 is wrapped around the outer surface of the housing 11 along its circumference, enabling rapid coverage of a wider area of ​​the outer surface of the housing 11, thereby improving the insulation performance of the battery cell 10. By wrapping the first insulating member 3 around the outer surface of the housing 11 along its circumference and overlapping its two ends, a first thickened region 31 is formed. Forming the first thickened region 31 is simple. When wrapping the first insulating member 3 around the outer surface of the housing 11, the position of the weld mark 111 can be more easily determined, enabling rapid coverage of the weld mark 111 by the first thickened region 31, thereby improving production efficiency.

[0144] In some embodiments, referring to FIG. 8 , the housing 11 includes a first wall portion 1121 , the weld print area 111 is located on the first wall portion 1121 , and the first insulating portion 32 and the second insulating portion 33 jointly cover the outer surface of the first wall portion 1121 .

[0145] The first wall portion 1121 is a wall portion in the housing 11. The first wall portion 1121, in which the weld mark 111 is formed, comprises two parts, which are welded together to form the weld mark 111. Taking the housing 11 as a rectangular parallelepiped as an example, the housing 11 includes four circumferentially arranged walls, two of which are oppositely arranged along the width of the housing 11, and two of which are arranged along the height of the housing 11. The walls along the width of the housing 11 may be the first wall portion 1121, and the walls along the length of the housing 11 may be the first wall portion 1121.

[0146] The portion of the first insulating member 3 located on the first wall portion 1121 may be the first insulating portion 32 and the second insulating portion 33 , so that the first insulating portion 32 and the second insulating portion 33 jointly cover the outer surface of the first wall portion 1121 .

[0147] In this embodiment, the first insulating portion 32 and the second insulating portion 33 jointly cover the outer surface of the first wall portion 1121 where the weld mark area 111 is formed, thereby achieving insulation of the first wall portion 1121 and further improving the insulation performance of the battery cell 10 .

[0148] In some embodiments, referring to FIG. 8 , the first thickened area 31 completely covers the weld print area 111 .

[0149] It can be understood that the projection of the weld mark area 111 along the wall thickness direction of the shell 11 is entirely located within the first thickened area 31 .

[0150] In this embodiment, the first thickened area 31 completely covers the weld mark area 111 , increasing the overlapping area between the first thickened area 31 and the weld mark area 111 , and further reducing the risk of the weld mark area 111 puncturing the first insulating member 3 .

[0151] In some embodiments, please refer to Figure 10, which is a partial enlarged view of point B in Figure 8. Along the circumference of the shell 11, the width of the first thickened area 31 is W1, and the width of the weld mark area 111 is W2, where W1>W2.

[0152] As an example, the housing 11 includes a first wall portion 1121, the weld print region 111 is located in the first wall portion 1121, and the thickened region is located in the first wall portion 1121 to cover at least a portion of the weld print region 111. The width direction of the first thickened region 31 is consistent with the width direction of the weld print region 111, and both are perpendicular to the thickness direction of the first wall portion 1121.

[0153] In this embodiment, W1>W2, and the first thickened area 31 has more area that can be used to cover the weld print area 111.

[0154] In some embodiments, W1-W2≥1 mm.

[0155] W1-W2 can be any point value of 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, etc., or a range value between any two of them.

[0156] In this embodiment, the first thickened area 31 has a large covering margin, which is conducive to achieving complete coverage of the weld print area 111 by the first thickened area 31, can meet the alignment accuracy requirements of the first thickened area 31 and the weld print area 111, and improve the assembly efficiency of the first insulating member 3 and the shell 11.

[0157] In some embodiments, W1 ≥ 3 mm.

[0158] W1 can be any point value of 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, etc., or a range value between any two of them.

[0159] When the shell 11 is welded, the width of the weld mark area 111 formed by the welding of the shell 11 is generally between 0.2 mm and 2 mm. Therefore, W1 ≥ 3 mm, so that the first thickened area 31 has a larger width and can cover more areas of the weld mark area 111, which is conducive to achieving full coverage of the weld mark area 111 by the first thickened area 31.

[0160] In some embodiments, referring to FIG. 10 , the weld mark area 111 includes a first protrusion 1111 protruding from the outer surface of the shell 11 . The height of the first protrusion 1111 protruding from the outer surface of the shell 11 is H1 . The thickness of the first thickened area 31 is D1 , and H1 < D1 .

[0161] The height direction of the first protrusion 1111 and the thickness direction of the first thickened region 31 are both aligned with the thickness direction of the first wall portion 1121. For example, the first insulating portion 32 and the second insulating portion 33 of the first insulating member 3 form a first overlapping region, corresponding to the formation of the first thickened region 31. The total thickness of the first insulating portion 32 and the second insulating portion 33 is the thickness D1 of the first thickened region 31.

[0162] In this embodiment, H1<D1. Even if the first protrusion 1111 completely penetrates the first thickened area 31, it is difficult to puncture the first thickened area 31, further reducing the risk of insulation failure of the battery cell 10.

[0163] In some embodiments, please refer to FIG11 , which is a schematic structural diagram of a housing 11 provided in some embodiments of the present application. Housing 11 is formed by bending a sheet material. Along the circumference of housing 11 , the sheet material includes a first end 11211 and a second end 11212 . First end 11211 and second end 11212 are welded together to form a weld mark 111 .

[0164] The first end 11211 and the second end 11212 are the two ends of the plate respectively. The weld mark area 111 is the weld mark portion formed after the first end 11211 and the second end 11212 are welded, and the first end 11211 and the second end 11212 are fixedly connected by the weld mark area 111.

[0165] Before forming, the housing 11 may be made of a rectangular plate, which can be bent to form a cylindrical housing, a prismatic housing, etc. The prism may be a triangular prism, a quadrangular prism, a pentagonal prism, a hexagonal prism, etc. As an example, as shown in FIG11 , the housing 11 is a rectangular parallelepiped housing.

[0166] Please refer to Figure 12, which is a schematic diagram of the structure of the shell 11 after unfolding provided by some embodiments of the present application. Before the shell 11 is formed, the plate has two opposite end faces, namely a first end face 11213 and a second end face 11214. The portion of the plate that is offset from the first end face 11213 in the direction close to the second end face 11214 within the region of the third preset distance L3 is a first end 11211 of the plate, and the length of the first end 11211 is equal to the third preset distance L3; the portion of the plate that is offset from the second end face 11214 in the direction close to the first end face 11213 within the region of the fourth preset distance L4 is a second end 11212 of the plate, and the length of the second end 11212 is equal to the second preset distance L4. The third preset distance L3 and the fourth preset distance L4 can be equal or different.

[0167] As an example, the housing 11 includes multiple wall portions 112 and multiple corner portions 113. Along the circumference of the housing 11, each corner portion 113 connects two adjacent wall portions 112. The weld mark 111 can be located in a corner portion 113 or in a wall portion 112. As shown in FIG11 , taking the weld mark 111 located in a wall portion 112 as an example, the wall portion 112 includes two portions, which can serve as a first end portion 11211 and a second end portion 11212, respectively.

[0168] In this embodiment, the molding method of the housing 11 is simple, which can effectively reduce the difficulty of molding the housing 11. In addition, when molding the housing 11, it is only necessary to weld the first end 11211 and the second end 11212 of the plate, and form a weld mark area 111 in the welding area of ​​the first end 11211 and the second end 11212, thereby providing the housing 11 with excellent strength.

[0169] 11 to 13 , FIG13 is a schematic structural diagram of the housing 11 shown in FIG11 after removing the weld mark area 111. The end surface of the first end 11211 and the end surface of the second end 11212 are welded together.

[0170] The end surface of the first end portion 11211 and the end surface of the second end portion 11212 are the two opposing end surfaces of the plate material of the housing 11. The end surfaces of the first end portion 11211 and the second end portion 11212 are respectively the first end surface 11213 and the second end surface 11214. The first end surface 11213 and the second end surface 11214 can be flat or curved, and the curved surface can be an arcuate surface, a serrated surface, or the like. The first end surface 11213 and the second end surface 11214 are welded together, forming a weld seam between the first end surface 11213 and the second end surface 11214. The weld mark 111 is formed at the weld seam.

[0171] The outer surface of the first end portion 11211 can be flush with the outer surface of the second end portion 11212. The portion of the weld mark 111 that protrudes from the outer surfaces of the first end portion 11211 and the outer surfaces of the second end portion 11212 is the first protrusion 1111. Along the thickness direction of the first end portion 11211, the surface of the first end portion 11211 facing away from the interior of the housing 11 is the outer surface of the first end portion 11211. Along the thickness direction of the second end portion 11212, the surface of the second end portion 11212 facing away from the interior of the housing 11 is the outer surface of the second end portion 11212. The thickness direction of the first end portion 11211 is consistent with the thickness direction of the second end portion 11212.

[0172] In this embodiment, the end face of the first end 11211 and the end face of the second end 11212 are welded together. On the one hand, there is no overlapping part after the two ends of the plate are connected, which saves materials and reduces the production cost of the shell 11; on the other hand, it makes the shell 11 flatter and can increase the internal space of the shell 11, which is beneficial to improving the energy density of the battery cell 10.

[0173] In some embodiments, referring to Figures 14 and 15 , Figure 14 is a schematic structural diagram of the housing 11 provided in other embodiments of the present application; Figure 15 is a partial enlarged view of point C in Figure 14 . The first end 11211 and the second end 11212 have a second overlapping region 11215 , and the weld mark 111 is located in the second overlapping region 11215 .

[0174] The part where the first end 11211 and the second end 11212 overlap with each other is the second overlapping area 11215. It can be understood that a part of the second overlapping area 11215 is located at the first end 11211, and the other part of the second overlapping area 11215 is located at the second end 11212.

[0175] As an example, as shown in FIG15 , in second overlapping region 11215, second end 11212 is located outside first end 11211, and the portion of weld print region 111 protruding from the outer surface of second end 11212 is first protrusion 1111. Along the thickness direction of second end 11212, the surface of second end 11212 facing away from the interior of housing 11 is the outer surface of second end 11212.

[0176] In this embodiment, the first end portion 11211 and the second end portion 11212 have a second overlapping area 11215, and the weld mark area 111 is located in the second overlapping area 11215, which can reduce the difficulty of welding the first end portion 11211 and the second end portion 11212, increase the contact area between the first end portion 11211 and the second end portion 11212, and improve the connection strength between the first end portion 11211 and the second end portion 11212.

[0177] 11 , 13 , and 14 , the housing 11 includes a plurality of walls 112 and a plurality of corners 113 . Each corner 113 connects two adjacent walls 112 along the circumference of the housing 11 . The weld mark 111 is located on the wall 112 .

[0178] It is understood that along the circumference of the shell 11, the corner portions 113 and the wall portions 112 are alternately arranged, and the multiple wall portions 112 and the multiple corner portions 113 form a closed structure connected end to end. If the shell 11 is a triangular prism, the shell 11 can have three wall portions 112, and the three wall portions 112 are respectively located on the three sides of the triangle; if the shell 11 is a quadrangular prism, the shell 11 can have four wall portions 112, and the four wall portions 112 are respectively located on the four sides of the quadrilateral; if the shell 11 is a pentagonal prism, the shell 11 can have five wall portions 112, and the five wall portions 112 are respectively located on the five sides of the pentagon; if the shell 11 is a hexagonal prism, the shell 11 can have six wall portions 112, and the six wall portions 112 are respectively located on the six sides of the hexagon.

[0179] The corner portion 113 is a portion connecting two adjacent wall portions 112 and located at a corner position of the housing 11. The cross section of the corner portion 113 may be arc-shaped, and the cross section of the corner portion 113 is parallel to the thickness direction of the two wall portions 112 connected to the corner portion 113.

[0180] In the housing 11, if the housing 11 has only one welding position, the housing 11 has only one weld mark area 111, and the weld mark area 111 is correspondingly located on one wall portion 112 of the housing 11. As shown in Figures 11, 13, and 14, taking the example of the housing 11 being formed by bending a sheet material, and the weld mark area 111 being formed by welding the first end 11211 and the second end 11212 of the sheet material, the housing 11 has only one weld mark area 111.

[0181] In the housing 11, if the housing 11 has multiple welding locations, the housing 11 also has multiple weld imprint areas 111. For example, if the housing 11 has two welding locations, the housing 11 has two weld imprint areas 111, and the two weld imprint areas 111 can be located on the two walls 112 of the housing 11, respectively.

[0182] In this embodiment, the weld mark area 111 is set on the wall portion 112 instead of the corner portion 113, which can reduce the difficulty of positioning the shell 11 during the welding forming process, thereby reducing the difficulty of forming the shell 11, and can improve the connection strength of the shell 11 at the welding position, thereby improving the strength of the shell 11.

[0183] In some embodiments, the multiple wall portions 112 include a first wall portion 1121 and a second wall portion 1122. The first wall portion 1121 and the second wall portion 1122 are connected by a corner portion 113. The second wall portion 1122 is the wall portion 112 with the largest outer surface area in the shell 11. The weld print area 111 is located on the first wall portion 1121.

[0184] The first wall portion 1121 and the second wall portion 1122 are two adjacent wall portions 112 in the housing 11, connected by a corner portion 113. In this embodiment, the housing 1 may be a triangular prism, a quadrangular prism, a pentagonal prism, a hexagonal prism, or the like. In the housing 11, the first wall portion 1121 and the second wall portion 1122 may be one or more. The first wall portion 1121 forming the weld mark 111 comprises two parts, which are welded together to form the weld mark 111.

[0185] Since the second wall portion 1122 is the wall portion 112 with the largest outer surface area in the shell 11, when the electrode assembly 2 inside the battery cell 10 (located inside the shell 11) expands, the second wall portion 1122 is more easily deformed than the first wall portion 1121. Setting the weld mark area 111 on the first wall portion 1121 with a smaller deformation amount can, on the one hand, reduce the risk of the shell 11 being damaged in the weld mark area 111 when the electrode assembly 2 expands, and on the other hand, reduce the risk of the weld mark area 111 puncturing the first insulating member 3 when the electrode assembly 2 expands.

[0186] 11 , 13 , and 14 , the plurality of walls 112 include two first walls 1121 and two second walls 1122 . The two first walls 1121 are disposed opposite each other along a first direction X, and the two second walls 1122 are disposed opposite each other along a second direction Y. The first direction X is perpendicular to the second direction Y. A weld mark 111 is formed on at least one of the first walls 1121 .

[0187] The first direction X may be the height direction of the shell 11 , and the second direction Y may be the width direction of the shell 11 . The height of the shell 11 is greater than the width of the shell 11 , so that the second wall portion 1122 is the wall portion 112 with the largest outer surface area in the shell 11 .

[0188] Of the two first walls 1121 of the housing 11, one may be formed with the weld mark 111, or both may be formed with the weld mark 111. As an example, one of the first walls 1121 of the housing 11 is formed with the weld mark 111, and the first end 11211 and the second end 11212 of the plate of the housing 11 together constitute the first wall 1121.

[0189] In this embodiment, the housing 11 has a simple quadrangular prism structure. When the electrode assembly 2 within the battery cell 10 expands, the electrode assembly 2 expands more in the second direction Y than in the first direction X. This causes the deformation of the two second walls 1122 after being squeezed by the electrode assembly 2 to be greater than the deformation of the two first walls 1121. Therefore, positioning the weld print area 111 on the first wall 1121 can reduce the impact of the electrode assembly 2 expansion on the weld print area 111, improve the structural strength of the housing 11, and reduce the risk of the weld print area 111 puncturing the first insulating member 3.

[0190] It can be seen from the above embodiments that in the shell 11, only one first wall portion 1121 may be formed with a weld mark area 111. In other embodiments, please refer to Figures 16 and 17. Figure 16 is an assembly diagram of the shell 11 and the first insulating member 3 provided in other embodiments of the present application, and Figure 17 is a structural schematic diagram of the shell 11 shown in Figure 16. Alternatively, both first wall portions 1121 in the shell 11 may be formed with a weld mark area 111.

[0191] It is understood that there are two weld imprints 111 in the housing 11, one located on each of the two first walls 1121. In an embodiment where the first insulating member 3 includes a first insulating portion 32 and a second insulating portion 33, and the first overlapping region between the first and second insulating portions 32, 33 forms the first thickened region 31, the first insulating member 3 may include two sheets disposed on the outer surface of the housing 11, with both ends of one sheet forming the first insulating portion 32, and both ends of the other sheet forming the second insulating portion 33. A first insulating portion 32 of one sheet and a second insulating portion 33 of the other sheet form a first overlapping region, which covers the weld imprint 111 on one first wall 1121. Another first insulating portion 32 of one sheet and another second insulating portion 33 of the other sheet form another first overlapping region, which covers the weld imprint 111 on the other first wall 1121.

[0192] Please refer to Figure 18, which is an isometric view of the housing 11 provided in some embodiments of the present application. In some embodiments, the battery cell 10 further includes a pressure relief mechanism 6, and the pressure relief mechanism 6 and the weld mark area 111 are respectively located on the two wall portions 112.

[0193] The pressure relief mechanism 6 is a component for releasing the internal pressure of the battery cell 10. When the internal pressure of the battery cell 10 reaches a threshold value, the internal pressure of the battery cell 10 is released through the pressure relief mechanism 6.

[0194] The wall portion 112 where the pressure relief mechanism 6 is located and the wall portion 112 where the weld mark area 111 is located may be two adjacent wall portions 112 , or they may be connected via other wall portions 112 .

[0195] The pressure relief mechanism 6 and the housing 11 can be an integral structure. For example, a notched groove is provided on the wall portion 112 of the housing 11, and the area of ​​the wall portion 112 where the notched groove is provided corresponds to the pressure relief mechanism 6. The notched groove can be a groove of various shapes, such as a linear groove, a circular groove, an elliptical groove, an annular groove, an arc-shaped groove, a U-shaped groove, an H-shaped groove, etc. Among them, a circular groove refers to a groove with a circular cross-section, and an elliptical groove refers to a groove with an elliptical cross-section, where the cross-section is perpendicular to the thickness direction of the wall portion 112 where the notched groove is provided. As an example, in FIG. 18 , the notched groove is an annular groove.

[0196] The pressure relief mechanism 6 and the housing 11 may also be separate components. The pressure relief mechanism 6 and the housing 11 are separate components that are molded separately and then assembled together. The pressure relief mechanism 6 may be an explosion-proof valve, explosion-proof disk, or other component. The pressure relief mechanism 6 may be attached to the wall 112 of the housing 11 by bonding, welding, or other methods.

[0197] In this embodiment, the pressure relief mechanism 6 and the weld mark area 111 are respectively located on two wall portions 112, and the pressure relief mechanism 6 and the weld mark area 111 are not set on the same wall portion 112, thereby reducing the impact on the pressure relief mechanism 6 during the process of welding the shell 11 to form the weld mark area 111, and improving the reliability of the pressure relief mechanism 6.

[0198] In some embodiments, please continue to refer to FIG. 18 , the plurality of wall portions 112 include two opposite first wall portions 1121 , and the pressure relief mechanism 6 and the weld print area 111 are respectively located on the two first wall portions 1121 .

[0199] The two first wall portions 1121 are two opposite wall portions 112 in the housing 11 .

[0200] As an example, the plurality of walls further include two opposing second walls 1122. The first wall 1121 and the second wall 1122 are connected by a corner. The two first walls 1121 are disposed opposite each other along a first direction X, and the two second walls 1122 are disposed opposite each other along a second direction Y. The first walls 1121 are perpendicular to the second walls 1122. Along the first direction X, the spacing between the two first walls 1121 is greater than the spacing between the two second walls 1122.

[0201] In this embodiment, the pressure relief mechanism 6 and the weld mark area 111 are respectively located on the two first wall portions 1121, so that the pressure relief mechanism 6 and the weld mark area 111 are farther apart in the circumferential direction of the shell 11, further reducing the impact on the pressure relief mechanism 6 during the process of welding the shell 11 to form the weld mark area 111.

[0202] In some embodiments, please refer to Figures 19-21. Figure 19 is a schematic diagram of the structure of a battery cell 10 provided in some embodiments of the present application; Figure 20 is a partial enlarged view of point D in Figure 19; and Figure 21 is a partial enlarged view of point E in Figure 20. The battery cell 10 also includes an electrode assembly 2 and a second insulating member 4. The electrode assembly 2 is disposed within the housing 11. The second insulating member 4 is disposed between the electrode assembly 2 and the housing 11 and is configured to insulate and isolate the electrode assembly 2 from the housing 11.

[0203] The second insulating member 4 has a second thickened area 41 , and the second thickened area 41 covers at least a portion of the weld mark area 111 .

[0204] The second insulating member 4 is an insulating component disposed between the electrode assembly 2 and the shell 11 , and is made of an insulating material such as rubber, plastic, etc.

[0205] The second insulating member 4 can be an integrally formed insulating sleeve structure; the second insulating member 4 can also be formed by a sheet surrounding the electrode assembly 2. The second insulating member 4 can be formed by connecting the end portions of a sheet together; the second insulating member 4 can also be formed by multiple sheets, with the multiple sheets being provided separately and the connected two sheets being connected to each other.

[0206] The second thickened region 41 is a locally thickened area on the second insulating member 4. The second thickened region 41 may be formed by forming a protrusion on a portion of the second insulating member 4, or by overlapping two portions of the second insulating member 4, making the overlapping region thicker.

[0207] The second thickened region 41 can correspond one-to-one with the weld imprint region 111, or one first thickened region 31 can correspond to multiple weld imprint regions 111. The second thickened region 41 covers at least a portion of the weld imprint region 111, with the projection of the weld imprint region 111 along the thickness of the housing 11 at least partially located within the second thickened region 41. The second thickened region 41 can completely cover the weld imprint region 111, meaning that the projection of the weld imprint region 111 along the thickness of the housing 11 is entirely located within the second thickened region 41. Alternatively, the second thickened region 41 can cover a portion of the weld imprint region 111, meaning that a portion of the projection of the weld imprint region 111 along the thickness of the housing 11 is located within the second thickened region 41. The second thickened region 41 and the weld imprint region 111 can be in contact or separated by a gap. As an example, in FIG. 21 , a gap is provided between the second thickened region 41 and the weld imprint region 111, making it more difficult for the weld imprint region 111 to pierce the second insulating member 4. Taking the shell 11 having two opposite first wall portions 1121 as an example, one first wall portion 1121 is located at the bottom of the electrode assembly 2 to support the electrode assembly 2, and the other wall portion 112 is located at the top of the electrode assembly 2 and forms a weld print area 111. In this way, under the action of gravity of the electrode assembly 2, a gap is set between the second thickened area 41 of the second insulating member 4 and the weld print area 111.

[0208] The second insulating member 4 is located between the electrode assembly 2 and the housing 11, separating the electrode assembly 2 and the housing 11 to achieve insulation between the electrode assembly 2 and the housing 11. The second thickened region 41 of the second insulating member 4 covers at least a portion of the weld mark region 111, thereby reducing the risk of the weld mark region 111 puncturing the second insulating member 4 and causing insulation failure between the electrode assembly 2 and the housing 11.

[0209] In some embodiments, referring to FIG. 20 and FIG. 21 , the second insulating member 4 includes a third insulating portion 42 and a fourth insulating portion 43 . The third insulating portion 42 and the fourth insulating portion 43 have a third overlapping region, and the third overlapping region forms a second thickened region 41 .

[0210] The second insulating member 4 can be formed by a single piece disposed around the housing 11, with the third insulating portion 42 and the fourth insulating portion 43 being two integrally formed parts of the second insulating member 4. The third insulating portion 42 and the fourth insulating portion 43 can also be separate and connected. For example, the second insulating member 4 can be formed by multiple separate pieces disposed around the housing 11, with adjacent pieces connected to each other. Of the two adjacent pieces, all or part of one piece forms the third insulating portion 42, and all or part of the other piece forms the fourth insulating portion 43. The third insulating portion 42 and the fourth insulating portion 43 form a third overlapping region. Of course, the second insulating member 4 can comprise two, three, four, or more pieces.

[0211] The overlapping portion of the third insulating portion 42 and the fourth insulating portion 43 constitutes the second thickened region 41. It is understood that a portion of the second thickened region 41 is located in the third insulating portion 42, while another portion of the second thickened region 41 is located in the fourth insulating portion 43. Within the second thickened region 41, the third insulating portion 42 and the fourth insulating portion 43 can be connected in various ways, such as adhesive bonding or heat-seal bonding. The thickness of the third insulating portion 42 and the fourth insulating portion 43 can be equal or different.

[0212] The third insulating portion 42 and the fourth insulating portion 43 overlap to form a third overlapping region, thereby locally thickening the second insulating member 4 to form a corresponding second thickened region 41. The molding direction of the second thickened region 41 is simple. It can be understood that the second insulating member 4 has two layers of insulating portions in the third overlapping region, and this area does not have a double-layer structure. For example, in the third overlapping region, the third insulating portion 42 is located on the side of the fourth insulating portion 43 facing the electrode assembly 2. Even if the weld mark 111 punctures the fourth insulating portion 43, it is unlikely to puncture the third insulating portion 42. The third insulating portion 42 can still provide good insulation protection, thereby reducing the risk of the weld mark 111 puncturing the second insulating member 4.

[0213] In some embodiments, please continue to refer to Figures 19 to 21. The second insulating member 4 is wrapped around the outer surface of the electrode assembly 2 along the circumference of the shell 11. Along the circumference of the shell 11, the two ends of the second insulating member 4 form a third insulating portion 42 and a fourth insulating portion 43 respectively.

[0214] The circumferential direction of the shell 11 is consistent with the circumferential direction of the electrode assembly 2 .

[0215] In this embodiment, the second insulating member 4 can be formed from a single piece disposed around the housing 11 along its circumference. The third insulating portion 42 and the fourth insulating portion 43 are the two end portions of the second insulating member 4. It is understood that the two ends of the second insulating member 4 form a third overlapping region. The portion of the second insulating member 4 extending from one end surface along the positive direction of the circumference of the housing 11 within a fifth preset distance L5 is one end portion of the second insulating member 4, and the length of this end portion is equal to the fifth preset distance L5. The portion of the second insulating member 4 extending from the other end surface along the negative direction of the circumference of the housing 11 within a sixth preset distance L6 is the other end portion of the second insulating member 4, and the length of this end portion is equal to the sixth preset distance L6. The first preset distance L5 and the second preset distance L6 can be equal or different. As an example, the weld mark area 111 is located on the first wall 1121 of the housing 11. The third insulating portion 42 and the fourth insulating portion 43 are disposed opposite the first wall 1121, and a gap is formed between the third wall 112 and the fourth wall 112.

[0216] In this embodiment, the second insulating member 4 is wrapped around the outer surface of the electrode assembly 2 along the circumference of the housing 11, enabling rapid coverage of more areas of the outer surface of the electrode assembly 2, thereby improving the insulation performance between the electrode assembly 2 and the housing 11. By wrapping the second insulating member 4 around the outer surface of the electrode assembly 2 along the circumference of the housing 11 and overlapping the two ends of the second insulating member 4, a second thickened region 41 is formed. The second thickened region 41 is formed in a simple manner.

[0217] In some embodiments, referring to FIG. 21 , the second thickened area 41 completely covers the weld print area 111 .

[0218] It can be understood that the projection of the weld mark area 111 along the wall thickness direction of the shell 11 is entirely located within the second thickened area 41 .

[0219] In this embodiment, the second thickened area 41 completely covers the second protrusion 1112 , increasing the overlapping area between the second thickened area 41 and the weld mark area 111 , further reducing the risk of the weld mark area 111 puncturing the second insulating member 4 .

[0220] In some embodiments, please continue to refer to Figure 21, the weld print area 111 includes a second protrusion 1112 protruding from the inner surface of the shell 11, the height of the second protrusion 1112 protruding from the inner surface of the shell 11 is H2, the thickness of the second thickened area 41 is D2, and H2<D2.

[0221] The second protrusion 1112 is the portion of the weld mark area 111 protruding from the inner surface of the shell 11. The second protrusion 1112 may be solder or welding slag formed during the welding process of the shell 11. The second protrusion 1112 may also be the portion protruding from the outer surface of the shell 11 after the welding parts are fused.

[0222] The height direction of the second protrusion 1112 and the thickness direction of the second thickened region 41 are both aligned with the thickness direction of the first wall portion 1121. For example, the third insulating portion 42 and the fourth insulating portion 43 of the second insulating member 4 form a third overlapping region, corresponding to the second thickened region 41. The total thickness of the third insulating portion 42 and the fourth insulating portion 43 is the thickness D2 of the second thickened region 41.

[0223] In this embodiment, H2<D2, even if the second protrusion 1112 completely penetrates the second thickened area 41, it is difficult to puncture the second thickened area 41, further reducing the risk of insulation failure between the electrode assembly 2 and the shell 11.

[0224] In some embodiments, please refer to FIG. 22 , which is an isometric view of a housing 11 provided in some other embodiments of the present application. The housing 11 is a rectangular parallelepiped housing. This type of housing 11 is suitable for rectangular parallelepiped battery cells 10 and can meet the large capacity requirements of the battery cells 10.

[0225] In some embodiments, openings are formed at opposite ends of the housing 11 along the length direction of the housing 11. The length of the housing 11 is a, the width of the housing 11 is b, and the height of the housing 11 is c, where b≤c≤a / 1.5.

[0226] It is understood that a / c ≥ 1.5, and a / c can be any value among 1.5, 2, 3, 4, 5, etc., or a range of values ​​between any two. b < c or b = c can be used. In the embodiment shown in FIG22 , b < c.

[0227] As an example, the housing 11 includes two first walls 1121 and a second wall 1122, which are connected by a corner portion 113. The two first walls 1121 are arranged opposite each other along a first direction X, the weld mark 111 is formed on one of the two first walls 1121, and the two second walls 1122 are arranged opposite each other along a second direction Y. The two openings of the housing 11 are arranged opposite each other along a third direction Z, and the first direction X, the second direction Y, and the third direction Z are perpendicular to each other. The first direction X can be the height direction of the housing 11, the second direction Y can be the width direction of the housing 11, and the third direction Z can be the length direction of the housing 11.

[0228] The housing 11 is in an elongated strip shape, which helps increase the energy density of the battery cell 10. In embodiments where the housing 11 is formed by bending a sheet of material, and the two ends of the sheet are welded together to form a welded area 111, the housing 11 formed by bending the sheet of material is easier to form than by conventional stamping or drawing, and has higher molding efficiency and a higher yield rate, especially for thin-walled housings 11 with a wall thickness of no more than 0.6 mm.

[0229] 4 , openings are formed at opposite ends of the housing 11. The battery cell 10 further includes end caps 12, which correspond to the openings one by one and seal the openings.

[0230] The two openings are arranged opposite to each other along the third direction Z. The circumference of the housing 11 is arranged around the center line, and the center line extends along the third direction Z.

[0231] Exemplarily, the end caps 12 are provided with electrode terminals 5. In the battery cell 10, one end cap 12 is provided with a positive electrode terminal, and the other end cap 12 is provided with a negative electrode terminal. The electrode assembly 2 has a positive tab and a negative tab. The positive tab and the negative tab are formed at opposite ends of the electrode assembly 2 along the third direction Z. The positive tab is electrically connected to the positive electrode terminal, and the negative tab is electrically connected to the negative electrode terminal.

[0232] When assembling the battery cell 10 , the electrode assembly 2 can enter the housing 11 from the opening at any end of the housing 11 , which can effectively improve the assembly efficiency of the battery cell 10 .

[0233] An embodiment of the present application provides a battery 100 , comprising the battery cell 10 provided in any one of the above embodiments.

[0234] An embodiment of the present application provides an electrical device, comprising a battery cell 10 provided by any one of the above embodiments, wherein the battery cell 10 is used to provide electrical energy.

[0235] The present embodiment provides a battery cell 10, comprising a housing 11, an end cap 12, an electrode assembly 2, a first insulating member 3, and a second insulating member 4. The housing 11 is a rectangular parallelepiped housing, comprising two first walls 1121 and two second walls 1122, connected by a corner portion 113. The two first walls 1121 are arranged opposite each other along a first direction X, and the two second walls 1122 are arranged opposite each other along a second direction Y. The second walls 1122 are the walls 112 of the housing 11 with the largest outer surface area. The housing 11 has two openings, which are arranged opposite each other along a third direction Z. The first direction X, the second direction Y, and the third direction Z are perpendicular to each other. The housing 11 is formed by bending a sheet material. Along the circumference of the housing 11, the sheet material includes a first end 11211 and a second end 11212. The first end 11211 and the second end 11212 are welded together to form a weld mark 111. The weld mark 111 includes a first protrusion 1111 protruding from the outer surface of the housing 11 and a second protrusion 1112 protruding from the inner surface of the housing 11. Two end caps 12 are provided, each sealing the two openings of the housing 11. One end cap 12 is provided with a positive electrode terminal, and the other end cap 12 is provided with a negative electrode terminal. The electrode assembly 2 is disposed within the housing 11. A positive tab and a negative tab are formed at each end of the electrode assembly 2 along the third direction Z. The positive tab is electrically connected to the positive electrode terminal, and the negative tab is electrically connected to the negative electrode terminal. The first insulating member 3 covers the outer surface of the shell 11 along its circumference. Along the circumference of the shell 11, the two ends of the first insulating member 3 have a first overlap region, forming a first thickened region 31 of the first insulating member 3. The first thickened region 31 completely covers the weld mark 111. Along the circumference of the shell 11, the width of the first thickened region 31 is W1, where W1 ≥ 3 mm. The width of the first protrusion 1111 is W2, where W1 - W2 ≥ 1 mm. The height of the first protrusion 1111 above the outer surface of the shell 11 is H1, and the thickness of the first thickened region 31 is D1, where H1 < D1. The second insulating member 4 covers the outer surface of the electrode assembly 2 along its circumference. Along the circumference of the shell 11, the two ends of the second insulating member 4 have a second overlap region 11215, forming a second thickened region 41 of the second insulating member 4. The second thickened region 41 completely covers the weld mark 111. The height of the second protrusion 1112 protruding from the inner surface of the housing 11 is H2, and the thickness of the second thickened area 41 is D2, where H2<D2.

[0236] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0237] The above embodiments are intended only to illustrate the technical solutions of this application and are not intended to limit this application. Those skilled in the art will appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this application are intended to be within the scope of protection of this application.

Claims

1. A battery cell, comprising: A housing having a weld print area; The first insulating member is arranged on the outer surface of the shell, and the first insulating member has a first thickened area, and the first thickened area covers at least a part of the weld print area.

2. The battery cell according to claim 1, wherein: The first insulating member includes a first insulating portion and a second insulating portion, wherein the first insulating portion and the second insulating portion are disposed on an outer surface of the shell, and the first insulating portion and the second insulating portion have a first overlapping area, and the first overlapping area forms the first thickened area.

3. The battery cell according to claim 2, wherein: The first insulating member is covered on the outer surface of the shell along the circumference of the shell, and two ends of the first insulating member along the circumference of the shell form the first insulating portion and the second insulating portion respectively.

4. The battery cell according to claim 2 or 3, wherein: The shell includes a first wall portion, the weld print area is located on the first wall portion, and the first insulating portion and the second insulating portion jointly cover an outer surface of the first wall portion.

5. The battery cell according to any one of claims 1 to 4, wherein: The first thickened area completely covers the weld print area.

6. The battery cell according to any one of claims 1 to 5, wherein: Along the circumference of the shell, the width of the first thickened area is W1, the width of the weld print area is W2, and W1>W2.

7. The battery cell according to claim 6, wherein: W1-W2≥1mm.

8. The battery cell according to claim 6 or 7, wherein: W1≥3mm.

9. The battery cell according to any one of claims 1 to 8, wherein: The weld print area includes a first convex portion protruding from the outer surface of the shell, the height of the first convex portion protruding from the outer surface of the shell is H1, the thickness of the first thickened area is D1, and H1<D1.

10. The battery cell according to any one of claims 1 to 9, wherein: The shell is formed by bending a plate material. Along the circumference of the shell, the plate material includes a first end and a second end. The first end and the second end are welded and connected to form the weld print area.

11. The battery cell according to claim 10, wherein: The end surface of the first end portion and the end surface of the second end portion are connected by welding.

12. The battery cell according to claim 10, wherein: The first end portion and the second end portion have a second overlapping area, and the weld print area is located in the second overlapping area.

13. The battery cell according to any one of claims 1 to 12, wherein: The shell includes a plurality of wall portions and a plurality of corner portions, and along the circumference of the shell, each of the corner portions connects two adjacent wall portions; Wherein, the welding area is located on the wall portion.

14. The battery cell according to claim 13, wherein: The multiple wall portions include a first wall portion and a second wall portion, the first wall portion and the second wall portion are connected via a corner portion, the second wall portion is the wall portion with the largest outer surface area in the shell, and the weld print area is located on the first wall portion.

15. The battery cell according to claim 14, wherein: The multiple wall portions include two first wall portions and two second wall portions, the two first wall portions are arranged opposite to each other along a first direction, the two second wall portions are arranged opposite to each other along a second direction, and the first direction is perpendicular to the second direction; Wherein, at least one of the first wall portions is formed with the weld print area.

16. The battery cell according to any one of claims 13 to 15, wherein: The battery cell further includes a pressure relief mechanism, and the pressure relief mechanism and the weld print area are respectively located on the two wall portions.

17. The battery cell according to claim 16, wherein: The multiple wall portions include two opposite first wall portions, and the pressure relief mechanism and the weld print area are respectively located on the two first wall portions.

18. The battery cell according to any one of claims 1 to 17, wherein: The battery cell further comprises: An electrode assembly is disposed in the housing; A second insulating member is disposed between the electrode assembly and the housing, and the second insulating member is configured to insulate and isolate the electrode assembly from the housing; The second insulating member has a second thickened area, and the second thickened area covers at least a portion of the weld print area.

19. The battery cell according to claim 18, wherein: The second insulating member includes a third insulating portion and a fourth insulating portion, wherein the third insulating portion and the fourth insulating portion have a third overlapping region, and the third overlapping region forms the second thickened region.

20. The battery cell according to claim 19, wherein: The second insulating member is coated on the outer surface of the electrode assembly along the circumference of the shell, and two ends of the second insulating member along the circumference of the shell form the third insulating portion and the fourth insulating portion respectively.

21. The battery cell according to any one of claims 18 to 20, wherein: The second thickened area completely covers the weld print area.

22. The battery cell according to any one of claims 18 to 21, wherein: The weld print area includes a second convex portion protruding from the inner surface of the shell, the height of the second convex portion protruding from the inner surface of the shell is H2, the thickness of the second thickened area is D2, and H2<D2.

23. The battery cell according to any one of claims 1 to 22, wherein: The shell is a rectangular parallelepiped shell.

24. The battery cell according to claim 23, wherein: Along the length direction of the shell, openings are formed at two opposite ends of the shell; The length of the shell is a, the width of the shell is b, the height of the shell is c, and b≤c≤a / 1.

5.

25. The battery cell according to any one of claims 1 to 24, wherein: The shell has openings formed at opposite ends; The battery cell further includes an end cover, the end cover corresponds to the opening one by one, and the end cover closes the opening.

26. A battery comprising the battery cell according to any one of claims 1 to 25.

27. An electrical device comprising the battery cell according to any one of claims 1 to 25, wherein the battery cell is used to provide electrical energy.

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