Battery monomer, battery and electric device

Abstract

The invention provides a battery monomer, a battery and a power utilization device. The battery cell includes a housing and a plurality of electrode assemblies. The multiple electrode assemblies are contained in the shell and arranged in the first direction, each electrode assembly comprises a first pole piece and a second pole piece which are opposite in polarity, the first pole pieces and the second pole pieces are arranged in a stacked mode in the second direction, and the first direction intersects with the second direction. The reliability of the battery monomer can be improved.

Description

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] Battery cells are widely used in electronic devices, such as mobile phones, laptop computers, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and electric tools, etc. Battery cells can include nickel-cadmium battery cells, nickel-hydrogen battery cells, lithium-ion battery cells, and secondary alkaline zinc-manganese battery cells, etc.

[0003] In the development of battery technology, how to improve battery reliability has always been a research direction in battery technology. Summary of the invention

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

[0005] On the one hand, an embodiment of the present application provides a battery cell. It includes a housing, a plurality of electrode assemblies, a first electrode terminal, a second electrode terminal, a first adapter, and a second adapter. The plurality of electrode assemblies are accommodated in the housing, and the plurality of electrode assemblies are arranged along a first direction, each electrode assembly includes a first pole piece and a second pole piece with opposite polarities, and the first pole piece and the second pole piece are stacked along a second direction, and the first direction and the second direction intersect.

[0006] In the above scheme, multiple electrode assemblies are arranged along a first direction, and the first direction intersects with a second direction, so that the relative area between adjacent electrode assemblies is reduced, thereby accelerating the speed at which heat generated by the electrode assemblies during operation dissipates, thereby improving the heat dissipation performance of the battery cell and improving the reliability of the battery cell.

[0007] In some embodiments, the electrode assembly also includes: the first electrode piece also includes a first electrode ear; the second electrode piece also includes a second electrode ear; the first electrode terminal and the second electrode terminal are arranged on the outer shell; a first adapter and a second adapter, the first adapter connects the first electrode ears and the first electrode terminal of multiple electrode assemblies, and the second adapter connects the second electrode ears and the first electrode terminal of multiple electrode assemblies.

[0008] In the above solution, achieving electrical connection between the tab and the electrode terminal through the adapter can reduce the connection difficulty and improve the reliability of the electrical connection between the tab and the electrode terminal.

[0009] In some embodiments, the first electrode tab and the second electrode tab are disposed on one side of the electrode assembly along the third direction. In the first direction, the first electrode tab and the second electrode tab do not overlap, and the first direction, the second direction and the third direction intersect each other.

[0010] In the above scheme, the first pole ear and the second pole ear do not overlap in the first direction, which can simplify the connection structure between multiple pole ears, thereby reducing the space occupied by the connection structure in the shell, improving energy density, reducing the possibility of short circuit between pole ears of different polarities, and improving the reliability of the battery cell.

[0011] In some embodiments, a first electrode tab of one of two adjacent electrode assemblies is disposed adjacent to a second electrode tab of the other electrode assemblies along a first direction.

[0012] In the above scheme, the connection structure of the same polarity tabs in multiple electrode assemblies can be simplified, the manufacturing cost of the adapter can be reduced, and the possibility of interference between the adapter and other components in the housing can be reduced.

[0013] In some embodiments, the outer shell includes multiple accommodating cavities, and multiple electrode assemblies are arranged in the multiple accommodating cavities in a one-to-one manner, thereby reducing the possibility of relative movement between the electrode assemblies when subjected to external vibrations, thereby reducing the possibility of poor electrical contact between the electrode assemblies and the electrode terminals, and improving the reliability of the battery cells.

[0014] In some embodiments, the housing includes a shell, an end cover and a partition, the shell has an opening, the end cover covers the opening, the first electrode terminal and the second electrode terminal are arranged on the end cover along a first direction, and the opening is divided into multiple accommodating cavities by the partition.

[0015] In the above scheme, when the electrode assembly is placed in the accommodating cavity, the partition can limit the electrode assembly, reducing the possibility of interference between electrode assemblies in different accommodating cavities. In addition, the partition can support the shell, thereby enhancing the rigidity of the shell, reducing the possibility of deformation of the shell under external force, and improving the reliability of the battery cell.

[0016] In some embodiments, two adjacent accommodating chambers are interconnected so that the amounts of electrolyte in different accommodating chambers can be exchanged, thereby reducing the possibility of differences in the amounts of electrolyte in different accommodating chambers, improving the performance uniformity of different electrode assemblies, and thus improving the reliability of the battery cells.

[0017] In some embodiments, a gap is provided between the inner wall of at least one of the shell and the end cover and the partition plate, and two adjacent accommodating chambers are connected to each other through the gap.

[0018] In the above solution, the communication mode between different accommodating chambers can be simplified, the content of electrolyte in the battery cell can be increased, and the service life of the battery cell can be improved.

[0019] In some embodiments, the electrode assembly further includes a body portion, the first electrode tab and the second electrode tab are disposed on one side of the body portion, and along the third direction, the distance between the partition and the end cover is greater than the distance between the body portion and the end cover.

[0020] In the above scheme, during the battery assembly process, the pole ear usually needs to be folded down, that is, bent toward the main body. Through the above setting, the possibility of contact between the pole ear and the partition can be reduced, thereby reducing the possibility of short circuit between the pole ear and the partition, thereby improving the battery manufacturing yield.

[0021] In some embodiments, the partition includes a through hole, and two adjacent accommodating cavities are connected to each other through the through hole.

[0022] In the above solution, the difficulty of the connection process between different accommodating chambers is reduced while the connection surface between the partition and the shell is improved.

[0023] In some embodiments, the dimension of the partition along the first direction is greater than or equal to the thickness of the side wall of the shell, which is beneficial to enhancing the rigidity of the middle area of ​​the shell, reducing the possibility of deformation of the shell due to insufficient strength of the middle area, and further reducing the possibility of the shell squeezing the electrode assembly, resulting in uneven force on the electrode assembly during operation and causing capacity diving, thereby improving the service life of the battery.

[0024] In some embodiments, the first electrode tab and the second electrode tab are disposed on both sides of the electrode assembly along the third direction, and the length of the first electrode tab and / or the second electrode tab along the first direction is less than or equal to the length of the electrode assembly along the first direction.

[0025] In the above scheme, it is beneficial to increase the length of the pole ear, thereby increasing the current carrying capacity of the pole ear and improving the charging and discharging speed.

[0026] In some embodiments, the first electrode tab and the second electrode tab are disposed on one side of the electrode assembly along the first direction. The two electrode assemblies constitute an electrode assembly group, and in each electrode assembly group, an arrangement space is provided between the two electrode assemblies along the first direction, and the first electrode tabs and the second electrode tabs of the two electrode assemblies are both disposed in the arrangement space.

[0027] In the above scheme, it is helpful to improve the arrangement flexibility of the electrode tabs and the electrode assembly to meet the different design requirements of the electrode assembly and the electrode tabs.

[0028] In some embodiments, a plurality of electrode assembly groups are sequentially arranged along the first direction and / or the third direction, and the first direction, the second direction, and the third direction intersect with each other.

[0029] In the above scheme, it is beneficial to improve the energy density of the battery monomer and improve the applicability of the battery monomer.

[0030] In some embodiments, the first adapter includes a first connection portion and a second connection portion connected to each other, a plurality of first tabs are electrically connected through the first connection portion, and the second connection portion is electrically connected to the first electrode terminal. The second adapter includes a third connection portion and a fourth connection portion connected to each other, a plurality of second tabs are electrically connected through the third connection portion, and the fourth connection portion is electrically connected to the second electrode terminal. At least one of the first connection portion and the third connection portion is provided with an insulating layer on its surface.

[0031] In the above solution, the possibility of short circuit between the first adapter and the second adapter is reduced, thereby improving the reliability of the battery cell.

[0032] In some embodiments, the electrode assembly includes a negative electrode plate, the negative electrode plate includes a negative electrode active material layer, the active material weight per unit area of ​​the negative electrode active material layer is CW, the side wall thickness of the shell is H, and CW and H satisfy the relationship 4.22≤50 / H+0.23CW≤7.55.

[0033] In the above solution, the charging speed of the battery cell is improved while the heat dissipation performance and the rigidity of the battery housing are balanced.

[0034] In some embodiments, the electrode assembly is a wound structure, the first electrode tab and the second electrode tab are respectively located on two sides of a reference plane, and the reference plane passes through the winding axis of the electrode assembly and is perpendicular to the second direction.

[0035] In the above scheme, the first pole ear and the second pole ear are divided into different sides by the reference plane, which is helpful to reduce the difficulty of yield detection during the manufacturing process of the electrode assembly and reduce the manufacturing cost of the electrode assembly.

[0036] In some embodiments, in each electrode assembly, the first electrode tab and the second electrode tab are both bent toward a side away from the reference plane.

[0037] In the above scheme, it is helpful to reduce the possibility of the first pole ear and the second pole ear overlapping along the first direction due to the influence of manufacturing accuracy, and it can also reduce the space occupied by the first pole ear and the second pole ear along the second direction, which is conducive to the lightness and thinness of the battery cell.

[0038] In a second aspect, an embodiment of the present application provides a battery, comprising a battery cell in any of the aforementioned embodiments.

[0039] In a third aspect, an embodiment of the present application provides an electrical device, comprising a battery in any of the aforementioned embodiments, and the battery is used to provide electrical energy.

[0040] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0042] Figure 1 is a structural schematic diagram of a vehicle provided in an embodiment of the present application;

[0043] Figure 2 is a schematic diagram of an exploded structure of a battery provided in an embodiment of the present application;

[0044] Figure 3 is a structural schematic diagram of a battery module provided in an embodiment of the present application;

[0045] Figure 4 is a schematic diagram of the internal structure of a battery cell provided in an embodiment of the present application;

[0046] Figure 5 is a structural schematic diagram of an electrode assembly provided in an embodiment of the present application;

[0047] Figure 6 is a schematic diagram of a cross-sectional structure of a battery cell provided in an embodiment of the present application;

[0048] Figure 7 is a schematic diagram of the internal structure of another battery cell provided in an embodiment of the present application;

[0049] Figure 8 is a schematic cross-sectional structure diagram of another battery cell provided in an embodiment of the present application;

[0050] Fig. 9 is a schematic cross-sectional structure diagram of another battery cell provided in an embodiment of the present application;

[0051] Fig.10 is a schematic cross-sectional structure diagram of another battery cell provided in an embodiment of the present application;

[0052] Fig.11 is a schematic cross-sectional structure diagram of another battery cell provided in an embodiment of the present application;

[0053] Fig.12 yes Figure 4 Schematic diagram of the cross-sectional structure of AA.

[0054] In the attached figure:

[0055] 1000. Vehicles;

[0056] 100, battery; 110, battery cell; 200, controller; 300, motor; 400, housing; 410, first housing portion; 420, second housing portion; 430, storage portion; 500, battery module;

[0057] 10. housing; 11. accommodating chamber; 12. shell; 13. end cover; 14. partition; 141. gap; 142. through hole;

[0058] 20. electrode assembly; 21. first electrode tab; 22. second electrode tab; 23. main body;

[0059] 31. a first electrode terminal; 32. a second electrode terminal;

[0060] 41, first adapter; 411, first connection portion; 412, second connection portion; 42, second adapter; 421, third connection portion; 422, fourth connection portion;

[0061] 50. Insulation layer;

[0062] P1, reference plane;

[0063] X, first direction; Y, second direction; Z, third direction. DETAILED DESCRIPTION

[0064] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0065] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0066] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

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

[0068] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0069] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0070] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0071] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0072] In the embodiment of the present application, the battery cell may be a secondary battery cell, which refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0073] The battery cells can be lithium-ion battery cells, sodium-ion battery cells, sodium-lithium-ion battery cells, lithium metal battery cells, sodium metal battery cells, lithium-sulfur battery cells, magnesium-ion battery cells, nickel-hydrogen battery cells, nickel-cadmium battery cells, lead-acid battery cells, etc., which are not limited in the embodiments of the present application.

[0074] A battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode and a negative electrode. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are inserted and removed back and forth between the positive electrode and the negative electrode.

[0075] In some embodiments, the electrode assembly further includes a separator, which is disposed between the positive electrode and the negative electrode to prevent the positive and negative electrodes from short-circuiting while allowing active ions to pass through.

[0076] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet may include a positive electrode current collector and a positive electrode active material layer disposed on at least one surface of the positive electrode current collector.

[0077] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material layer is disposed on any one or both of the two facing surfaces of the positive electrode current collector.

[0078] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, stainless steel, copper, aluminum, nickel, silver-surface-treated aluminum, silver-surface-treated stainless steel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base 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 polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0079] As an example, the positive electrode active material layer includes a positive electrode active material. 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 positive electrode active materials for batteries can also be used. These positive electrode active materials can be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates may include, but are not limited to, 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 at least one of 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 0.80 Co 0.15 Al 0.05 O2) and its modified compounds, etc.

[0080] In some embodiments, the positive electrode may be carbon foam or metal foam. The metal foam may be nickel foam, copper foam, aluminum foam or alloy foam. When the metal foam is used as the positive electrode, the positive electrode active material may not be provided on the surface of the metal foam, but the positive electrode active material may also be provided. As an example, lithium source material, potassium metal or sodium metal may be filled or / and deposited in the metal foam, and the lithium source material is lithium metal and / or lithium-rich material.

[0081] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector.

[0082] As an example, the negative electrode current collector may be a metal foil, a foamed metal, a foamed carbon or a composite current collector. For example, as a metal foil, stainless steel, copper, aluminum, nickel, silver-surface-treated aluminum, silver-surface-treated stainless steel, a carbon electrode, carbon, nickel or titanium, etc. may be used. The foamed metal may be a foamed nickel, a foamed copper, a foamed aluminum or a foamed alloy, etc. The composite current collector may include a polymer material base and a metal layer. The composite current collector may 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 polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0083] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells 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.

[0084] In some embodiments, the negative electrode may be foamed carbon or foamed metal. The foamed metal may be foamed nickel, foamed copper, foamed aluminum or foamed alloy, etc. When the foamed metal is used as the negative electrode sheet, the surface of the foamed metal may not be provided with a negative electrode active material, but of course, a negative electrode active material may also be provided.

[0085] As an example, a lithium source material, potassium metal or sodium metal may be filled or / and deposited in the negative electrode current collector, and the lithium source material is lithium metal and / or lithium-rich material.

[0086] 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.

[0087] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode sheet and the negative electrode sheet.

[0088] 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 stability and mechanical stability can be selected.

[0089] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without special restrictions. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without special restrictions. The separator can be a separate component located between the positive and negative electrodes, or it can be attached to the surface of the positive and negative electrodes.

[0090] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode sheet and the negative electrode sheet and plays the role of transmitting ions and isolating the positive and negative electrodes.

[0091] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The present application has no specific restrictions on the type of electrolyte, which can be selected according to needs. The electrolyte can be liquid, gel or solid.

[0092] In some embodiments, the liquid electrolyte includes an electrolyte salt and a solvent.

[0093] In some embodiments, the electrolyte salt can 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.

[0094] 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, methyl propyl carbonate, ethyl propyl 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 selected from ether solvents. 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.

[0095] The gel electrolyte includes a polymer-based electrolyte skeleton network combined with an ionic liquid-lithium salt.

[0096] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0097] 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, and the like.

[0098] 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.

[0099] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0100] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0101] In some embodiments, the electrode assembly is a laminate structure.

[0102] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets may be provided respectively, and the plurality of positive electrode sheets and the plurality of negative electrode sheets may be alternately stacked.

[0103] 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.

[0104] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of folded sections that are stacked.

[0105] As an example, a plurality of separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0106] As an example, the separator may be disposed continuously, and may be disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0107] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0108] In some embodiments, the electrode assembly is provided with tabs, which can lead current out of the electrode assembly. The tabs include a positive tab and a negative tab.

[0109] In some embodiments, the 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 (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film.

[0110] As an example, the battery cell may be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes a square-shell battery cell, a blade-shaped battery cell, a polygonal battery, such as a hexagonal battery.

[0111] 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.

[0112] 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.

[0113] 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 accommodated in the case.

[0114] 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.

[0115] In some embodiments, the battery may be an energy storage device, which includes an energy storage container, an energy storage cabinet, and the like.

[0116] The development of battery technology must take into account many design factors at the same time, such as energy density, cycle life, discharge capacity, charge and discharge rate and other performance parameters. In addition, battery reliability must also be considered.

[0117] In order to increase the energy density of a battery cell, multiple electrode assemblies are usually stacked together to form a battery cell. However, increasing the energy density of a battery cell in the above manner will cause the electrode assemblies to generate a large amount of heat during the charging process and accumulate between the electrode assemblies, causing the charging temperature of the battery cell to rise, affecting the life and reliability of the battery.

[0118] In view of this, the present application provides a battery cell, which reduces the relative area between adjacent electrode assemblies by arranging multiple electrode assemblies along a first direction, and the first direction intersects with a second direction, thereby accelerating the speed of heat dissipation generated by the electrode assemblies during operation, thereby improving the heat dissipation performance of the battery cell and improving the reliability of the battery cell.

[0119] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using batteries, such as mobile phones, portable devices, laptop computers, electric vehicles, electric cars, ships, spacecraft, electric toys and electric tools, etc., wherein spacecrafts include airplanes, rockets, space shuttles and spacecrafts, etc., electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc., and electric tools include metal cutting power tools, grinding power tools, assembly power tools and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers.

[0120] The battery cells described in the embodiments of the present application are not limited to being applicable to the electrical devices described above, but for the sake of simplicity, the following embodiments are described using electric vehicles as examples.

[0121] See also Figure 1 , Figure 1 A simple schematic diagram of a vehicle provided in an embodiment of the present application. Vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 may be provided inside the vehicle 1000, and specifically, for example, a battery 100 may be provided at the bottom, front or rear of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used, for example, to control the battery to power the motor 300. The battery may be used for starting and navigating the vehicle 1000, and of course, the battery 100 may also be used to drive the vehicle 1000, replacing or partially replacing fuel or natural gas to provide drive for the vehicle 1000.

[0122] Figure 2 Schematic diagram of an explosion of a battery provided in some embodiments of the present application. Figure 2 As shown, the battery 100 includes a housing 400 and a battery cell (not shown in the figure), and the battery cell is accommodated in the housing 400 .

[0123] The box 400 is used to accommodate the battery cell, and the box 400 can be a variety of structures. In some embodiments, the box 400 may include a first box portion 410 and a second box portion 420, the first box portion 410 and the second box portion 420 cover each other, and the first box portion 410 and the second box portion 420 jointly define a receiving portion 430 for accommodating the battery cell. The second box portion 420 may be a hollow structure with one end open, the first box portion 410 is a plate-like structure, and the first box portion 410 covers the open side of the second box portion 420 to form a box with a receiving portion 430; the first box portion 410 and the second box portion 420 may also be a hollow structure with one side open, and the open side of the first box portion 410 covers the open side of the second box portion 420 to form a box 400 with a receiving portion 430. Of course, the first box portion 410 and the second box portion 420 may be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0124] In the battery 100, there can be one or more battery cells. If there are multiple battery cells, the multiple battery cells can be connected in series, in parallel, or in mixed connection. Mixed connection means that multiple battery cells are connected in series and in parallel. Multiple battery cells can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the multiple battery cells is accommodated in the box 400; of course, multiple battery cells can also be connected in series, in parallel, or in mixed connection to form a battery module 500, and multiple battery modules 500 are then connected in series, in parallel, or in mixed connection to form a whole, and accommodated in the box 400.

[0125] Figure 3 for Figure 2 Schematic diagram of the structure of the battery module shown.

[0126] In some embodiments, Figure 3 As shown, there are multiple battery cells 110, and the multiple battery cells 110 are first connected in series, in parallel, or in mixed series to form a battery module 500. The multiple battery modules 500 are then connected in series, in parallel, or in mixed series to form a whole, and are accommodated in a box.

[0127] Figure 4 It is a schematic diagram of the internal structure of a battery cell provided in an embodiment of the present application. Figure 5 It is a schematic diagram of the structure of an electrode assembly provided in an embodiment of the present application. Figure 6 : is a schematic diagram of a cross-sectional structure of a battery cell provided in an embodiment of the present application. ( Figure 4 The end caps of the battery cells are not shown.)

[0128] Reference Figures 4 to 6The embodiment of the present application provides a battery cell 110. It includes a housing 10 and a plurality of electrode assemblies 20. The plurality of electrode assemblies 20 are accommodated in the housing 10, and the plurality of electrode assemblies 20 are arranged along a first direction X. Each electrode assembly 20 includes a first pole piece and a second pole piece with opposite polarities, and the first pole piece and the second pole piece are stacked along a second direction, and the first direction and the second direction intersect.

[0129] Optionally, the housing 10 may include a housing cavity 11 and an electrode terminal lead-out hole, the electrode assembly 20 is disposed in the housing cavity 11, and at least a portion of the first electrode terminal 31 and the second electrode terminal 32 are located in the electrode terminal lead-out hole.

[0130] The first direction X and the second direction Y are arranged to intersect, and optionally, the first direction X and the second direction Y are arranged perpendicularly. It should be noted that the second direction Y is the stacking direction of the first pole piece and the second pole piece. Exemplarily, when the electrode assembly 20 is a winding structure, the electrode assembly 20 includes a straight area and a bending area, and the second direction Y is the stacking direction of the first pole piece and the second pole piece in the straight area. When the electrode assembly is a laminated structure, the second direction Y is the alternating stacking direction of multiple first pole pieces and multiple second pole pieces. The application is explained below by taking the battery assembly as a winding structure as an example.

[0131] A plurality of electrode assemblies 20 are arranged along a first direction X so that two smaller surfaces of adjacent electrode assemblies 20 are in contact with each other. The heat generated by the electrode assemblies 20 during operation is mostly dissipated by the outer shell 10, and the heat generated by the opposite surfaces between adjacent electrode assemblies 20 diffuses to the outer shell 10 through a shorter path, thereby reducing the possibility of heat accumulation between the opposite surfaces between adjacent electrode assemblies 20.

[0132] Optionally, the number of electrode assemblies 20 may include two, three, four or more. In the following description of the present application, the number of electrode assemblies 20 is two.

[0133] The battery cell 110 in the embodiment of the present application arranges a plurality of electrode assemblies 20 along a first direction X, and the first direction X intersects with a second direction Y, so that the relative area between adjacent electrode assemblies 20 is reduced, thereby accelerating the speed at which heat generated by the electrode assemblies 20 during operation dissipates, thereby improving the heat dissipation performance of the battery cell 110 and improving the reliability of the battery cell 110.

[0134] In some embodiments, see Figures 4 to 6The electrode assembly 20 further includes: the first electrode piece further includes a first electrode tab 21. The second electrode piece further includes a second electrode tab 22. The first electrode terminal 31 and the second electrode terminal 32 are disposed on the housing 10. The first adapter 41 connects the first electrode tabs 21 and the first electrode terminal 31 of the plurality of electrode assemblies 20, and the second adapter 42 connects the second electrode tabs 22 and the first electrode terminal 32 of the plurality of electrode assemblies 20.

[0135] Optionally, the first electrode tab 21 on the first electrode sheet and the second electrode tab 22 on the second electrode sheet may be disposed on the same side of the electrode assembly 20 , or may be disposed on different sides of the electrode assembly 20 .

[0136] The first adapter 41 connects the first tabs 21 of the plurality of electrode assemblies 20 and the first electrode terminal 31, that is, after the first tabs 21 of the plurality of electrode assemblies 20 are connected to each other, they are electrically connected to the outside world via the first electrode terminal 31. The second adapter 42 connects the second tabs 22 of the plurality of electrode assemblies 20 and the second electrode terminal 32, that is, after the second tabs 22 of the plurality of electrode assemblies 20 are connected to each other, they are electrically connected to the outside world via the second electrode terminal 32. In addition, the plurality of electrode assemblies 20 are connected in parallel through the first adapter 41 and the second adapter 42, so that the overall resistance of the battery cell 110 can be reduced.

[0137] Through the above arrangement, the embodiment of the present application can reduce the connection difficulty and improve the reliability of the electrical connection between the tab and the electrode terminal by using the adapter to achieve the electrical connection between the tab and the electrode terminal.

[0138] In some embodiments, see Figures 4 to 6 The first pole tab 21 and the second pole tab 22 are arranged on one side of the electrode assembly 20 along the third direction Z. In the first direction X, the first pole tab 21 and the second pole tab 22 do not overlap, and the first direction X, the second direction Y and the third direction Z intersect each other.

[0139] Optionally, the first pole tabs 21 of two adjacent electrode assemblies 20 may be arranged adjacent to each other, that is, in two adjacent electrode assemblies 20, the arrangement order of the pole tabs along the first direction X is the second pole tab 22 of the first electrode assembly 20, the first pole tab 21 of the first electrode assembly 20, the first pole tab 21 of the second electrode assembly 20, and the second pole tab 22 of the second electrode assembly 20. Of course, the arrangement order of the pole tabs of two adjacent electrode assemblies 20 along the first direction X may also be other arrangement orders, and the embodiment of the present application does not impose any special restrictions on this.

[0140] In the embodiment of the present application, in the first direction X, the first pole tab 21 and the second pole tab 22 do not overlap, in other words, the projection of the first pole tab 21 along the first direction X and the projection of the second pole tab 22 along the first direction X do not overlap. Optionally, the projection of the first pole tab 21 along the first direction X and the projection of the second pole tab 22 along the first direction X can be arranged at intervals. Alternatively, the projection edge of the first pole tab 21 along the first direction X and the projection edge of the second pole tab 22 along the first direction X are arranged to overlap.

[0141] In the embodiment of the present application, through the above arrangement, the first pole lug 21 and the second pole lug 22 do not overlap in the first direction X, which can simplify the connection structure between the multiple pole lugs, thereby reducing the space occupied by the connection structure in the shell, improving the energy density, reducing the possibility of short circuit between pole lugs of different polarities, and improving the reliability of the battery cell.

[0142] In some embodiments, see Figure 4 The first electrode tab 21 of one of the two adjacent electrode assemblies 20 is arranged adjacent to the second electrode tab 22 of the other electrode assemblies along the first direction X.

[0143] Taking the two adjacent electrode assemblies 20 as the first electrode assembly 20 and the second electrode assembly 20 as an example, the first electrode tab 21 of the first electrode assembly 20 and the second electrode tab 22 of the second electrode assembly 20 are arranged adjacent to each other. In addition, along the first direction X, the first electrode tab 21 of the first electrode assembly 20 and the second electrode tab 22 of the second electrode assembly 20 do not overlap. In other words, the projection of the first electrode tab 21 of the first electrode assembly 20 along the first direction X and the projection of the second electrode tab 22 of the second electrode assembly 20 along the first direction X do not overlap.

[0144] Optionally, the first electrode tabs 21 in the plurality of electrode assemblies 20 may be arranged at intervals along a straight line.

[0145] Optionally, the second electrode tabs 22 in the plurality of electrode assemblies 20 may be arranged at intervals along a straight line. Optionally, two straight lines are arranged in parallel.

[0146] Through the above arrangement, the embodiment of the present application can simplify the connection structure of the electrodes of the same polarity in the multiple electrode assemblies 20, reduce the manufacturing cost of the adapter, and reduce the possibility of interference between the adapter and other components in the housing 10.

[0147] Figure 7 This is a schematic diagram of the internal structure of another battery cell provided in an embodiment of the present application. Figure 8 It is a schematic diagram of the cross-sectional structure of another battery cell provided in an embodiment of the present application. Figure 7 The end caps of the battery cells are not shown.

[0148] In some embodiments, see Figure 7and Figure 8 The housing 10 includes a plurality of accommodating cavities 11, and a plurality of electrode assemblies 20 are arranged in the plurality of accommodating cavities 11 in a one-to-one manner, thereby reducing the possibility of relative movement between the electrode assemblies 20 when subjected to external vibrations, thereby reducing the possibility of poor electrical contact between the electrode assemblies 20 and the electrode terminals, and improving the reliability of the battery cell 110.

[0149] In the embodiment of the present application, multiple electrode assemblies 20 are arranged in a one-to-one manner in multiple accommodating cavities 11. In other words, the number of accommodating cavities 11 is the same as the number of electrode assemblies 20, and one electrode assembly 20 is arranged in one accommodating cavity 11.

[0150] In some embodiments, see Figure 7 and Figure 8 The housing 10 includes a shell 12, an end cover 13 and a partition 14. The shell 12 has an opening, and the end cover 13 covers the opening. The first electrode terminal 31 and the second electrode terminal 32 are arranged on the end cover 13 along the first direction X, and the opening is divided into a plurality of accommodating cavities 11 by the partition 14.

[0151] The end cap 13 and the shell 12 together enclose a housing chamber 11 for accommodating the electrode assembly 20 and the electrolyte. The shell 12 can be in various shapes, such as a cylinder, a cuboid, etc. The shape of the shell 12 can be determined according to the specific shape of the electrode assembly 20. For example, if the electrode assembly 20 is a cylindrical structure, a cylindrical shell 12 can be selected; if the electrode assembly 20 is a cuboid structure, a cuboid shell 12 can be selected.

[0152] In some examples, one end of the housing 12 has an opening, and one end cap 13 is provided to cover the opening of the housing 12. In other examples, both opposite ends of the housing 12 have openings, and two end caps 13 are provided, and the two end caps 13 cover the two openings of the housing 12 respectively.

[0153] The partition 14 divides the opening into a plurality of accommodating chambers 11. Optionally, each accommodating chamber 11 may be independent of each other, or adjacent accommodating chambers 11 may be connected to each other.

[0154] Optionally, the partition 14 and the shell 12 may be an integral structure. Of course, the partition 14 and the shell 12 may be separate structures.

[0155] As an example, the material of the housing 12 may include a conductive material, and the material of the partition 14 may include an insulating material.

[0156] Through the above arrangement, in the embodiment of the present application, when the electrode assembly 20 is placed in the accommodating cavity 11, the partition 14 can limit the electrode assembly 20, reducing the possibility of mutual interference between the electrode assemblies 20 in different accommodating cavities 11. In addition, the partition 14 can support the shell 12, thereby enhancing the rigidity of the shell 12, reducing the possibility of deformation of the shell 12 under the action of external force, and improving the reliability of the battery cell 110.

[0157] In some embodiments, see Figure 8 The two adjacent accommodating chambers 11 are interconnected so that the amounts of electrolyte in different accommodating chambers 11 can be exchanged, thereby reducing the possibility of differences in the amounts of electrolyte in different accommodating chambers 11, improving the performance uniformity of different electrode assemblies 20, and thus improving the reliability of the battery cell 110.

[0158] In some embodiments, see Figure 8 A gap 141 is provided between the inner wall of at least one of the shell 12 and the end cover 13 and the partition 14 , and two adjacent accommodating chambers 11 are connected to each other through the gap 141 .

[0159] Optionally, the shell 12 includes an inner side wall and an inner bottom wall, the side of the end cover 13 facing the accommodating cavity 11 includes an inner top wall, and a gap 141 is provided between at least one of the inner side wall, the inner bottom wall and the inner top wall and the partition 14 .

[0160] As an example, a gap 141 is provided between the inner bottom wall and the partition 14, and the electrolyte in the adjacent accommodating chambers 11 can move through the gap 141 between the inner bottom wall and the partition 14. Optionally, the length of the gap 141 between the inner bottom wall and the partition 14 along the third direction Z is d, and 3mm≤d≤5mm. Exemplarily, the length of the gap 141 between the inner bottom wall and the partition 14 along the third direction Z includes 3mm, 4mm or 5mm.

[0161] Through the above arrangement, the embodiment of the present application can simplify the communication mode between different accommodating cavities 11 , increase the content of electrolyte in the battery cell 110 , and improve the service life of the battery cell 110 .

[0162] In some embodiments, see Figure 8 The electrode assembly 20 also includes a main body 23 , a first electrode tab 21 and a second electrode tab 22 are arranged on one side of the main body 23 , and along the third direction Z, the distance between the partition 14 and the end cover 13 is greater than the distance between the main body 23 and the end cover 13 .

[0163] Optionally, the electrode assembly 20 is a laminated structure. As an example, the main body 23 is formed by alternately stacking a first pole piece and a second pole piece. A diaphragm is also provided between the first pole piece and the second pole piece. Taking the second pole piece as an example, the second pole piece includes a current collector. The area where the active material layer is coated on the current collector is the area constituting the main body 23, and the area where the active material layer is not coated on the current collector is the area constituting the pole ear.

[0164] In the embodiment of the present application, along the third direction Z, the spacing between the partition 14 and the end cover 13 is greater than the spacing between the main body 23 and the end cover 13. In other words, in the third direction Z, the side of the partition 14 facing the cover plate is not more than the side of the main body 23 facing the cover plate. Optionally, the orthographic projection of the partition 14 along the first direction X is located on the side of the orthographic projection of the pole ear along the first direction X away from the cover plate. For example, the edge of the orthographic projection of the partition 14 along the first direction X facing the cover plate is the first orthographic projection edge, and the orthographic projection of the pole ear root along the first direction X is the second orthographic projection edge, and the second orthographic projection edge is located between the first orthographic projection edge and the cover plate. Optionally, the spacing between the first orthographic projection edge and the second orthographic projection edge along the third direction Z is h, 3mm≤D≤5mm. Exemplarily, the spacing between the first orthographic projection edge and the second orthographic projection edge along the third direction Z includes 3mm, 4mm or 5mm. It can be understood that the electrode tabs include a first electrode tab 21 and a second electrode tab 22 , and the positional relationship between the electrode tabs and the partition 14 in the embodiment of the present application can be the positional relationship between the first electrode tab 21 and the partition 14 , or can be the positional relationship between the second electrode tab 22 and the partition 14 .

[0165] During the battery assembly process, the pole ear usually needs to be folded down, that is, bent toward the main body 23. Through the above arrangement, the possibility of contact between the pole ear and the partition 14 can be reduced, thereby reducing the possibility of short circuit between the pole ear and the partition 14 and improving the battery manufacturing yield.

[0166] In some embodiments, see Figure 8 The partition plate 14 includes a through hole 142 , and two adjacent accommodating chambers 11 are connected to each other through the through hole 142 .

[0167] Optionally, the number of the through hole 142 may include one, or may include a plurality.

[0168] Optionally, the shape of the through hole 142 may include but is not limited to one or a combination of circle, oval, square and rectangle.

[0169] Optionally, blind holes may be provided on the partition 14 to reduce the weight of the partition 14 .

[0170] The embodiment of the present application reduces the difficulty of the connection process between different accommodating chambers 11 through the above-mentioned arrangement, while increasing the connection surface between the partition 14 and the shell 12.

[0171] In some embodiments, see Figure 8 The dimension of the partition 14 along the first direction X is greater than or equal to the thickness of the side wall of the shell 12, which is beneficial to enhancing the rigidity of the middle area of ​​the shell 12, reducing the possibility of deformation of the shell 12 due to insufficient strength of the middle area, and further reducing the possibility of the shell 12 squeezing the electrode assembly 20, resulting in uneven force on the electrode assembly 20 during operation and causing capacity diving, thereby improving the service life of the battery.

[0172] Optionally, the dimension of the partition 14 along the first direction X may be the thickness dimension of the partition 14 itself. Exemplarily, the dimension of the partition 14 along the first direction X is h, the thickness of the side wall of the shell 12 is H, and H and h satisfy the relationship of 0≤hH≤0.3mm. Optionally, the relationship that H and h satisfy includes hH=0, hH=0.1mm, hH=0.2mm or hH=0.3mm. It can be understood that the side wall of the shell 12 may be the side wall of the shell 12 enclosing the accommodating cavity 11.

[0173] Fig. 9 It is a schematic diagram of the cross-sectional structure of another battery cell provided in an embodiment of the present application.

[0174] In some embodiments, see Fig. 9 The first electrode tab 21 and the second electrode tab 22 are respectively arranged on both sides of the electrode assembly 20 along the third direction Z, and the length of the first electrode tab 21 and / or the second electrode tab 22 along the first direction X is less than or equal to the length of the electrode assembly 20 along the first direction X.

[0175] In some examples, the length of the first electrode tab 21 along the first direction X is less than the length of the electrode assembly 20 along the first direction X. In other examples, the length of the first electrode tab 21 along the first direction X is equal to the length of the electrode assembly 20 along the first direction X.

[0176] In some examples, the length of the second electrode tab 22 along the first direction X is less than the length of the electrode assembly 20 along the first direction X. In other examples, the length of the second electrode tab 22 along the first direction X is equal to the length of the electrode assembly 20 along the first direction X.

[0177] Optionally, the first electrode terminal 31 and the second electrode terminal 32 are also disposed along two sides of the housing 10 along the third direction Z so as to be connected to the first electrode tab 21 and the second electrode tab 22 .

[0178] The above-mentioned configuration of the embodiment of the present application is conducive to increasing the length of the pole ear, thereby increasing the current carrying capacity of the pole ear and improving the charging and discharging speed. Fig.10 It is a schematic diagram of the cross-sectional structure of another battery cell provided in an embodiment of the present application.

[0179] In some embodiments, see Fig.10 The first electrode tab 21 and the second electrode tab 22 are arranged on one side of the electrode assembly 20 along the first direction X. The two electrode assemblies 20 constitute an electrode assembly group. In each electrode assembly group, an arrangement space is provided between the two electrode assemblies 20 along the first direction X, and the first electrode tabs 21 and the second electrode tabs 22 of the two electrode assemblies 20 are both arranged in the arrangement space.

[0180] Optionally, the battery may include one electrode assembly group. Or the battery may include multiple electrode assembly groups. Or the battery may include an electrode assembly group and a separate electrode assembly 20. For example, the battery includes one electrode assembly group and one electrode assembly 20, and the electrode lug of the electrode assembly 20 is located on one side along the third direction Z.

[0181] In each electrode assembly group, the tabs of the two electrode assemblies 20 are located between the two electrode assemblies 20. Optionally, the first tabs 21 and the second tabs 22 in the two electrode assemblies 20 are arranged non-overlappingly along the third direction Z to facilitate the connection of the first adapter 41 and the second adapter 42. Optionally, the first tabs 21 in the two electrode assemblies 20 are arranged adjacently along the first direction X so that the two first tabs 21 are located on both sides of the first adapter 41 along the first direction X. The second tabs 22 in the two electrode assemblies 20 are arranged adjacently along the first direction X so that the two second tabs 22 are located on both sides of the second adapter 42 along the first direction X.

[0182] The above-mentioned arrangement in the embodiment of the present application is conducive to improving the arrangement flexibility of the electrode tab and the electrode assembly 20 to meet different design requirements of the electrode assembly 20 and the electrode tab.

[0183] Fig.11 It is a schematic diagram of the cross-sectional structure of another battery cell provided in an embodiment of the present application.

[0184] In some embodiments, see Fig.11 , multiple electrode assembly groups are arranged in sequence along the first direction X and / or the third direction Z, and the first direction X, the second direction Y and the third direction Z intersect each other.

[0185] In some examples, a plurality of electrode assembly groups are arranged sequentially along the first direction X.

[0186] In some examples, a plurality of electrode assembly groups are arranged sequentially along the third direction Z.

[0187] In some other examples, a portion of the electrode assemblies 24 are arranged in sequence along the first direction X, and another portion of the electrode assemblies 24 are arranged in sequence along the third direction Z.

[0188] The above configuration in the embodiment of the present application is conducive to improving the energy density of the battery cell and improving the applicability of the battery cell.

[0189] Fig.12 yes Figure 4 Schematic diagram of the cross-sectional structure of AA.

[0190] In some embodiments, see Figure 4 and Fig.12 The first adapter 41 includes a first connection portion 411 and a second connection portion 412 connected to each other, a plurality of first tabs 21 are electrically connected through the first connection portion 411, and the second connection portion 412 is electrically connected to the first electrode terminal 31. The second adapter 42 includes a third connection portion 421 and a fourth connection portion 422 connected to each other, a plurality of second tabs 22 are electrically connected through the third connection portion 421, and the fourth connection portion 422 is electrically connected to the second electrode terminal 32. At least one of the first connection portion 411 and the third connection portion 421 is provided with an insulating layer on its surface.

[0191] Optionally, the first connection portion 411 and the second connection portion 412 may be an integral structure. Of course, the first connection portion 411 and the second connection portion 412 may be separate structures.

[0192] Optionally, the third connection portion 421 and the fourth connection portion 422 may be an integral structure. Of course, the third connection portion 421 and the fourth connection portion 422 may be a separate structure.

[0193] Optionally, the first connection portion 411 may be extended along the first direction X.

[0194] Optionally, the third connection portion 421 may be extended along the first direction X.

[0195] Optionally, an insulating material may be provided between the first connection portion 411 and the third connection portion 421. As an example, the side of the first connection portion 411 facing the third connection portion 421 is covered with an insulating layer 50. The side of the third connection portion 421 facing the first connection portion 411 is covered with an insulating layer 50. Alternatively, the entire surface of the first connection portion 411 is coated with an insulating layer 50, and the entire surface of the third connection portion 421 is coated with an insulating layer 50.

[0196] The embodiment of the present application reduces the possibility of short circuit between the first adapter 41 and the second adapter 42 through the above arrangement, thereby improving the reliability of the battery cell 110 .

[0197] In some embodiments, the electrode assembly 20 includes a negative electrode plate, the negative electrode plate includes a negative electrode active material layer, the active material weight per unit area of ​​the negative electrode active material layer is CW, the side wall thickness of the shell is H, and CW and H satisfy the relationship 4.22≤50 / H+0.23CW≤7.55.

[0198] In the embodiment of the present application, the negative electrode plate includes a negative electrode current collector and a negative electrode active material layer. The area where the negative electrode current collector is coated with the negative electrode active material layer is the main body 23. The unit area weight of the negative electrode active material layer is the ratio of the active material weight of the active material layer on one side of the main body 23 to the total area of ​​one side of the main body 23.

[0199] Specifically, the active material weight of the active material layer on one side of the body portion 23 is C, and the total area of ​​the body portion 23 on one side is S1 (ie, the area of ​​the portion of the negative electrode current collector covered by the body portion 23). At this time, the unit area weight of the negative electrode active material layer CW=C / S1.

[0200] The embodiment of the present application improves the charging speed of the battery cell 110 through the above arrangement while balancing the heat dissipation performance and the rigidity of the battery housing 12 .

[0201] In some embodiments, see Figure 5 The electrode assembly 20 is a winding structure, the first electrode tab 21 and the second electrode tab 22 are respectively located on both sides of the reference plane P1, and the reference plane P1 passes through the winding axis of the electrode assembly 20 and is perpendicular to the second direction Y.

[0202] Optionally, the electrode assembly 20 includes a positive electrode sheet and a negative electrode sheet, which are stacked and wound around a winding axis to form the electrode assembly 20. The reference plane P1 is a plane passing through the winding axis of the electrode assembly 20, and the reference plane P1 is also perpendicular to the second direction Y of the battery cell 110. The first pole tab 21 and the second pole tab 22 are respectively located on both sides of the reference plane P1, that is, the first pole tab 21 and the second pole tab 22 are spaced apart along the second direction Y. Of course, in some other examples, the reference plane P1 can also be arranged to intersect with the second direction Y of the battery cell 110.

[0203] In the embodiment of the present application, the first pole ear 21 and the second pole ear 22 are divided into different sides by the reference plane P1, which is beneficial to reducing the difficulty of yield detection of the electrode assembly 20 during the manufacturing process and reducing the manufacturing cost of the electrode assembly 20.

[0204] In some embodiments, see Figure 5 The first pole tab 21 and the second pole tab 22 are both bent toward a side away from the reference plane P1.

[0205] The first pole tab 21 and the second pole tab 22 are both bent toward the side away from the reference plane P1, that is, the first pole tab 21 is bent toward the side away from the reference plane P1, and the second pole tab 22 is bent toward the side away from the reference plane P1. Optionally, the bent portion of the first pole tab 21 can be located on the side of the first connecting portion 411 facing away from the end cap 13. Or the bent portion of the first pole tab 21 can be located on the side of the first connecting portion 411 facing the end cap 13. The bent portion of the second pole tab 22 is the same as the bent portion of the first pole tab 21, and will not be described in detail.

[0206] The above-mentioned arrangement of the embodiment of the present application is helpful to reduce the possibility of the first pole tab 21 and the second pole tab 22 overlapping along the first direction X due to the influence of manufacturing accuracy, and can also reduce the space occupied by the first pole tab 21 and the second pole tab 22 along the second direction Y, which is conducive to the lightweight and thinning of the battery cell 110.

[0207] In some other examples, the first pole tab 21 and the second pole tab 22 are both bent toward the side facing the reference plane P1. Alternatively, one of the first pole tab 21 and the second pole tab is bent toward the side facing the reference plane P1, and the other is bent toward the side away from the reference plane P1.

[0208] In a second aspect, an embodiment of the present application provides a battery, comprising a battery cell 110 in any of the aforementioned embodiments.

[0209] It should be noted that the battery provided in the embodiment of the present application has the beneficial effects of the battery cell 110 in any of the aforementioned embodiments. For details, please refer to the aforementioned description of the beneficial effects of the battery cell 110, and the embodiment of the present application will not be repeated here.

[0210] In a third aspect, an embodiment of the present application provides an electrical device, comprising a battery in any of the aforementioned embodiments, and the battery is used to provide electrical energy.

[0211] According to some embodiments of the present application, please refer to Figure 4 , Figure 5 , Figure 8 , Fig. 9 as well as Fig.12, the embodiment of the present application provides a battery cell 110. It includes a shell 10, a plurality of electrode assemblies 20, a first electrode terminal 31, a second electrode terminal 32, a first adapter 41 and a second adapter 42. A plurality of electrode assemblies 20 are accommodated in the shell 10, and the plurality of electrode assemblies 20 are arranged along the first direction X. A first pole ear 21 and a second pole ear 22 with opposite polarities are provided at one end of each electrode assembly 20 along the third direction Z. In the first direction X, the first pole ear 21 and the second pole ear 22 do not overlap, and the first direction X, the second direction Y and the third direction Z intersect each other; the first electrode terminal 31 and the second electrode terminal 32 are arranged in the shell 10; the first adapter 41 connects the first pole ear 21 and the first electrode terminal 31 of the plurality of electrode assemblies 20, and the second adapter 42 connects the second pole ear 22 and the first electrode terminal 31 of the plurality of electrode assemblies 20.

[0212] The first pole ear 21 of one of the two adjacent electrode assemblies 20 is arranged adjacent to the second pole ear 22 of the other electrode assembly along the first direction X to reduce the number of electrode terminals. The first adapter 41 and the second adapter 42 are insulated. And the surfaces of the first connecting portion and the third connecting portion are provided with an insulating layer. The housing 10 includes a shell 12, an end cover 13 and a partition 14. The shell 12 has an opening, and the end cover 13 covers the opening. The first electrode terminal 31 and the second electrode terminal 32 are arranged on the end cover 13 along the first direction X. The opening is divided into a plurality of accommodating cavities 11 by the partition 14, and the adjacent accommodating cavities 11 are connected to each other. A gap 141 is provided between the inner wall of at least one of the shell 12 and the end cover 13 and the partition 14, and the adjacent accommodating cavities 11 are connected to each other through the gap 141.

[0213] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: shell; A plurality of electrode assemblies are accommodated in the shell, the plurality of electrode assemblies are arranged along a first direction, each of the electrode assemblies comprises a first pole piece and a second pole piece with opposite polarities, the first pole piece and the second pole piece are stacked along a second direction, and the first direction and the second direction intersect.

2. The battery cell according to claim 1, characterized in that: The electrode assembly further comprises: The first pole piece further includes a first pole lug; The second pole piece further includes a second pole lug; A first electrode terminal and a second electrode terminal are disposed on the housing; A first adapter and a second adapter, wherein the first adapter connects the first electrode tabs of the plurality of electrode assemblies and the first electrode terminal, and the second adapter connects the second electrode tabs of the plurality of electrode assemblies and the first electrode terminal.

3. The battery cell according to claim 2, characterized in that: The first electrode tab and the second electrode tab are arranged on one side of the electrode assembly along the third direction. In the first direction, the first electrode tab and the second electrode tab do not overlap, and the first direction, the second direction and the third direction intersect each other.

4. The battery cell according to claim 3, characterized in that: The first electrode tab of one of two adjacent electrode assemblies is disposed adjacent to the second electrode tab of the other electrode assemblies along the first direction.

5. The battery cell according to claim 3, characterized in that: The shell includes a plurality of accommodating cavities, and the plurality of electrode assemblies are arranged in the plurality of accommodating cavities in a one-to-one manner.

6. The battery cell according to claim 5, characterized in that: The shell includes a shell, an end cover and a partition, the shell has an opening, the end cover covers the opening, the first electrode terminal and the second electrode terminal are arranged on the end cover along the first direction, and the opening is divided into a plurality of accommodating cavities by the partition.

7. The battery cell according to claim 6, characterized in that: Two adjacent accommodating chambers are connected to each other.

8. The battery cell according to claim 7, characterized in that: A gap is provided between the inner wall of at least one of the shell and the end cover and the partition plate, and two adjacent accommodating chambers are connected to each other through the gap.

9. The battery cell according to claim 8, characterized in that: The electrode assembly further includes a body portion, the first electrode tab and the second electrode tab are arranged on one side of the body portion, and along the third direction, a distance between the partition and the end cover is greater than a distance between the body portion and the end cover.

10. The battery cell according to claim 7, characterized in that: The partition plate comprises a through hole, and two adjacent accommodating chambers are connected to each other through the through hole.

11. The battery cell according to claim 6, characterized in that: A dimension of the partition along the first direction is greater than or equal to a thickness of a side wall of the housing.

12. The battery cell according to claim 2, characterized in that: The first electrode tab and the second electrode tab are respectively arranged on both sides of the electrode assembly along the third direction, and the length of the first electrode tab and / or the second electrode tab along the first direction is less than or equal to the length of the electrode assembly along the first direction.

13. The battery cell according to claim 2, characterized in that: The first electrode tab and the second electrode tab are arranged on one side of the electrode assembly along the first direction; The two electrode assemblies constitute an electrode assembly group. In each electrode assembly group, an arrangement space is provided between the two electrode assemblies along the first direction. The first electrode tabs and the second electrode tabs of the two electrode assemblies are both arranged in the arrangement space.

14. The battery cell according to claim 13, characterized in that: The plurality of electrode assembly groups are arranged in sequence along the first direction and / or the third direction, and the first direction, the second direction and the third direction intersect each other.

15. The battery cell according to claim 2, characterized in that: The first adapter comprises a first connecting portion and a second connecting portion connected to each other, the plurality of first tabs are electrically connected via the first connecting portion, and the second connecting portion is electrically connected to the first electrode terminal; The second adapter comprises a third connecting portion and a fourth connecting portion connected to each other, a plurality of the second electrode tabs are electrically connected via the third connecting portion, and the fourth connecting portion is electrically connected to the second electrode terminal; Wherein, an insulating layer is provided on the surface of at least one of the first connecting portion and the third connecting portion.

16. The battery cell according to claim 1, characterized in that: The electrode assembly includes a negative electrode plate, the negative electrode plate includes a negative electrode active material layer, the active material weight per unit area of ​​the negative electrode active material layer is CW, the side wall thickness of the shell is H, and CW and H satisfy the relationship of 4.22≤50 / H+0.23CW≤7.

55.

17. The battery cell according to claim 2, characterized in that: The electrode assembly is a winding structure, the first electrode tab and the second electrode tab are respectively located on two sides of a reference plane, and the reference plane passes through the winding axis of the electrode assembly and is perpendicular to the second direction.

18. The battery cell according to claim 17, characterized in that: The first pole tab and the second pole tab are both bent toward a side away from the reference plane.

19. A battery, characterized in that: include: A battery cell as claimed in any one of claims 1 to 18.

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

Images