Battery cell, battery, and electric device

Abstract

The present application provides a battery cell, a battery, and an electric device. The battery cell comprises a casing and electrode terminals. The casing has two first walls opposite to each other in a first direction and two second walls opposite to each other in a second direction, each first wall is connected to the two second walls, at least one first wall comprises a protruding part, and the protruding part protrudes towards the outside of the casing. The electrode terminals are arranged at the end portion of the casing in a third direction, and the first direction, the second direction, and the third direction are perpendicular to each other in pairs. The battery cell provided by the present application improves the heat dissipation area and the heat dissipation efficiency of the battery cell, and reduces the risk of thermal runaway of the battery cell, thereby improving the reliability of the battery cell.

Description

Battery cell, battery and electric device

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application CN202420805622.0, filed on April 18, 2024, entitled “Battery cell, battery and electric device”, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present application relates to the technical field of battery, in particular to a battery cell, a battery and an electric device. BACKGROUND

[0004] Batteries are widely used in electronic devices, such as mobile phones, laptops, electric cars, electric cars, electric planes, electric ships, electric toy cars, electric toy ships, electric toy planes and electric tools, etc.

[0005] In the development of battery cell technology, in addition to improving the performance of the battery cell, the reliability of the battery cell is also a problem that needs to be considered. Therefore, how to improve the reliability of the battery cell is a continuous improvement problem in the battery cell technology.

[0006] SUMMARY

[0007] The present application provides a battery cell, a battery and an electric device to improve the reliability of the battery cell.

[0008] The present application is achieved by the following technical solutions:

[0009] In a first aspect, the present application provides a battery cell, the battery cell comprising a housing and an electrode terminal; the housing has two first walls opposite along a first direction and two second walls opposite along a second direction, the first walls connecting the two second walls, the maximum distance between the two first walls along the first direction being smaller than the maximum distance between the two second walls along the second direction, at least one first wall comprising a protruding portion, the protruding portion being protrudingly arranged towards the outside of the housing; the electrode terminal is arranged at the end of the housing along a third direction, the first direction, the second direction and the third direction being perpendicular to each other.

[0010] According to the battery cell provided in the embodiments of the present application, the first wall of the shell is provided with the protruding portion, and the protruding portion is arranged to protrude outwardly from the shell. During the operation of the battery cell, heat can be dissipated through the first wall, which is conducive to increasing the heat dissipation area of the battery cell. After the battery cell is grouped, the gap between the first walls of the two adjacent battery cells is increased, which is conducive to further improving the heat dissipation efficiency of the battery cell. Therefore, the battery cell provided in the embodiments of the present application is conducive to improving the heat dissipation efficiency of the battery cell, reducing the temperature rise rate of the battery cell, and reducing the risk of thermal runaway of the battery cell, thereby improving the reliability of the battery cell.

[0011] According to some embodiments of the present application, the two first walls are each provided with the protruding portion.

[0012] In the above scheme, after the battery cell is grouped, the gap between the battery cell and the adjacent battery cell along the first direction is increased, which is conducive to further improving the heat dissipation efficiency of the battery cell and further reducing the risk of thermal runaway of the battery cell. Moreover, after the battery cell is grouped, the heat insulation requirement of the heat insulation member between the battery cells is further reduced, which is conducive to reducing the thickness of the heat insulation member, thereby improving the energy density of the battery.

[0013] According to some embodiments of the present application, the protruding portion is arc-shaped and arranged to protrude outwardly from the shell.

[0014] In the above scheme, the protruding portion is arc-shaped, which is conducive to the manufacturing of the first wall and simplifies the preparation process of the battery cell. Moreover, the arc-shaped protruding portion is in linear contact with the adjacent battery cell, which is conducive to reducing the contactable area of the adjacent battery cell and increasing the gap between the adjacent battery cells along the first direction, thereby further improving the heat dissipation efficiency of the battery cell.

[0015] According to some embodiments of the present application, the battery cell further comprises an electrode assembly accommodated in the shell, and the electrode assembly has a first surface arranged toward the protruding portion, and the first surface is arranged to protrude toward the protruding portion.

[0016] In the above scheme, the first wall of the electrode assembly is arranged to protrude toward the protruding portion, which is conducive to increasing the space occupied by the electrode assembly in the shell, thereby improving the group margin of the battery cell, reducing the risk of loosening of the electrode assembly, and improving the energy density of the battery cell.

[0017] According to some embodiments of the present application, the size of the second wall along the first direction is w, the protruding portion has a first cross section perpendicular to the third direction, the maximum size of the first cross section in the orthogonal projection on the plane parallel to the first direction and the third direction along the first direction is h, and h / w≤0.5.

[0018] In the above scheme, the h / w is set to be less than or equal to 0.5, so that the battery monomer has a high energy density under the premise of improving the heat dissipation efficiency of the battery monomer, so that the battery monomer achieves a better balance between the heat dissipation efficiency and the energy density.

[0019] According to some embodiments of the present application, 0.005≤h / w≤0.125.

[0020] In the above scheme, the h / w is set to be less than or equal to 0.5, so that the battery monomer has a high energy density under the premise of improving the heat dissipation efficiency of the battery monomer, so that the battery monomer achieves a better balance between the heat dissipation efficiency and the energy density.

[0021] According to some embodiments of the present application, the at least one first wall further comprises a flat portion, the flat portion being perpendicular to the first direction and being adjacent to the protruding portion.

[0022] In the above scheme, the first wall comprises a flat portion, which is beneficial to increase the space inside the battery monomer shell through the flat portion, increase the space occupancy of the electrode assembly inside the battery monomer, and further improve the energy density of the battery monomer.

[0023] According to some embodiments of the present application, the flat portion is arranged on both sides of the protruding portion along the second direction and is adjacent to the second wall.

[0024] In the above scheme, after the battery monomers are arranged along the first direction, there is a large space between the flat portions on both sides of the opposite protruding portions between adjacent battery monomers, which is beneficial to further improve the energy density of the battery monomer.

[0025] According to some embodiments of the present application, the protruding portion is arranged on both sides of the flat portion along the second direction and is adjacent to the second wall.

[0026] In the above scheme, after the battery monomers are arranged along the first direction, the protruding portions on both sides of the first wall form a large gap with the first wall of the adjacent battery monomer, so that it is still beneficial to improve the heat dissipation efficiency of the battery monomer.

[0027] According to some embodiments of the present application, the size of the flat portion along the second direction is L1, and the size of the shell along the second direction is L, and L1 / L≤0.5.

[0028] In the above scheme, after the battery monomers are arranged along the first direction, the battery monomers can be in contact with each other through the flat portion and the battery monomers adjacent along the first direction. The inventors have found through systematic analysis and long-term practice that setting L1 / L≤0.5 is beneficial to reduce the area of contact between two battery monomers adjacent along the first direction, and further improves the heat dissipation efficiency of the battery monomer.

[0029] In a second aspect, the battery provided in the embodiments of the present application includes a thermal insulation member and the battery cell provided in any of the embodiments described above, and a plurality of battery cells are arranged at least along a first direction, and the thermal insulation member is arranged between the first walls of two adjacent battery cells along the first direction.

[0030] The battery provided in the embodiments of the present application has the battery cell provided in any of the embodiments described above, so that the heat dissipation efficiency of the battery cell is improved, the temperature rise of the battery is reduced, and the risk of thermal runaway of the battery is reduced. In addition, the heat dissipation efficiency of the battery cell is improved, the heat insulation requirement of the thermal insulation member is reduced, so that the material requirement and the thickness requirement of the thermal insulation member of the battery are reduced, the overall space occupied by the thermal insulation member in the battery is reduced, and the energy density of the battery is improved.

[0031] According to some embodiments of the present application, the thermal insulation member includes thermal insulation glue, and the thermal insulation glue is filled between the first walls of two adjacent battery cells along the first direction.

[0032] In the above scheme, the thermal insulation member includes thermal insulation glue, and the thickness of the thermal insulation glue corresponding to different parts of the first wall can be flexibly set according to the specific shape of the first wall, so that the process difficulty of the assembly process of the battery is reduced.

[0033] In a third aspect, the power consumption device provided in the embodiments of the present application includes the battery cell or the battery provided in any of the embodiments described above, and the battery is used to provide electric energy.

[0034] The power consumption device provided in the embodiments of the present application has the same technical effects as the battery cell or the battery provided in any of the embodiments described above, and details are not repeated here.

[0035] Additional aspects and advantages of the present application will be given in part in the following description, and will become apparent from the following description, or will be learned by practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiments of the present application will be briefly introduced as follows. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating any creative labor on the basis of the drawings.

[0037] FIG. 1 is a structural schematic diagram of a vehicle provided in the embodiments of the present application;

[0038] FIG. 2 is a structural schematic diagram of a battery provided in the embodiments of the present application;

[0039] FIG. 3 is a structural schematic diagram of a battery module in the battery provided in the embodiments of the present application;

[0040] FIG. 4 is an exploded structural schematic diagram of a battery cell according to an embodiment of the present application;

[0041] FIG. 5 is a top view of a battery cell according to an embodiment of the present application;

[0042] FIG. 6 is a cross-sectional structural schematic diagram of a battery cell according to an embodiment of the present application;

[0043] FIG. 7 is a top view of another battery cell according to an embodiment of the present application;

[0044] FIG. 8 is a top view of yet another battery cell according to an embodiment of the present application;

[0045] FIG. 9 is a top view of still another battery cell according to an embodiment of the present application;

[0046] FIG. 10 is a top structural schematic diagram of a battery according to an embodiment of the present application.

[0047] In the drawings, the drawings are not drawn according to the actual proportions.

[0048] Explanation of Reference Signs:

[0049] 1, vehicle; 1a, motor; 1b, controller;

[0050] 10, battery; 11, case; 111, first sub-case; 112, second sub-case;

[0051] 20, battery module;

[0052] 30, battery cell; 31, housing; 311, shell; 312, end cap; 32, electrode assembly; 321, first surface; 33, electrode terminal;

[0053] 40, first wall; 41, protrusion; 42, flat portion;

[0054] 50, second wall;

[0055] 60, thermal insulator; 61, thermal insulating adhesive;

[0056] X, first direction; Y, second direction; Z, third direction. DETAILED DESCRIPTION

[0057] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in connection with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0058] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the specification herein is for describing particular embodiments only and is not intended to be limiting of the application. Unless otherwise defined, all terms used in disclosing the application, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms used herein should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly literal sense unless expressly so defined by the patentee.

[0059] Reference throughout this application to "example" means that a particular feature, structure, or characteristic described in connection with the example can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of other embodiments. It is expressly understood that any of the described embodiments of the application are combinable with each other.

[0060] In the description of the application, it is necessary to explain that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "attaching" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0061] The term "and / or" in this application is only a description of the association relationship between the associated objects, which means that there can be three relationships, for example, A and / or B can represent the existence of A alone, the existence of A and B together, and the existence of B alone. In addition, the character " / " in this application generally represents that the front and rear associated objects are in an "or" relationship.

[0062] "Multiple" appearing in this application refers to two or more (including two), and similarly, "multiple groups" refers to two or more groups (including two groups), and "multiple pieces" refers to two or more pieces (including two pieces).

[0063] In some embodiments, the battery can be a battery module, and when there are multiple battery monomers, the multiple battery monomers are arranged and fixed to form a battery module.

[0064] In some embodiments, the battery can be a battery pack, and the battery pack includes a box body and a battery monomer, and the battery monomer or the battery module is contained in the box body.

[0065] In some embodiments, the box can be part of a chassis structure of a vehicle. For example, portions of the box can become at least part of a floor of the vehicle, or portions of the box can become at least part of cross members and longitudinal members of the vehicle.

[0066] In some embodiments, the battery can be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, and the like.

[0067] In embodiments of the present application, the battery cell can be a secondary battery, which refers to a battery cell that can be used continuously by activating the active material through charging after the battery cell is discharged.

[0068] The battery cell can be, but is not limited to, a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, and the like.

[0069] The battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging of the battery cell, active ions (e.g., lithium ions) are inserted and extracted between the positive electrode and the negative electrode. The separator is disposed between the positive electrode and the negative electrode, and can prevent the positive and negative electrodes from short-circuiting while allowing the active ions to pass through.

[0070] In some embodiments, the positive electrode can be a positive electrode sheet, which can include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0071] As an example, the positive electrode current collector has two opposite surfaces in the thickness direction thereof, and the positive electrode active material is disposed on either one or both of the opposite surfaces of the positive electrode current collector.

[0072] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, stainless steel, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, or titanium, etc. with a silver plating surface treatment can be used. The composite current collector can include a high molecular material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a high molecular material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0073] As an example, the positive electrode active material can include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for batteries can also be used.

[0074] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative electrode current collector.

[0075] As an example, the negative electrode current collector can employ a metal foil or a composite current collector. For example, as the metal foil, aluminum subjected to silver plating on the surface, stainless steel subjected to silver plating on the surface, stainless steel, copper, aluminum, nickel, a carbon electrode, or the like can be employed.

[0076] In some embodiments, the negative electrode current collector has two surfaces opposite in the thickness direction thereof, and the negative electrode active material is disposed on either one or both of the two opposite surfaces of the negative electrode current collector.

[0077] As an example, the negative electrode active material can employ a negative electrode active material for a battery known in the art. As an example, the negative electrode active material can include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, a silicon-based material, a tin-based material, lithium titanate, and the like. The silicon-based material can be selected from at least one of elemental silicon, a silicon oxide compound, a silicon-carbon composite, a silicon-nitrogen composite, and a silicon alloy. The tin-based material can be selected from at least one of elemental tin, a tin oxide compound, and a tin alloy. However, the present application is not limited to these materials, and other conventional materials that can be used as a negative electrode active material for a battery can also be used. These negative electrode active materials can be used alone or in combination of two or more.

[0078] In some embodiments, the separator is a separator film. The present application does not particularly limit the type of the separator film, and any known porous structure separator film having good chemical stability and mechanical stability can be used.

[0079] As an example, the main material of the separator film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride, and ceramic. The separator film can be a single layer film or a multi-layer composite film, and is not particularly limited. When the separator film is a multi-layer composite film, the materials of the respective layers can be the same or different, and are not particularly limited. The separator can be a separate member located between the positive electrode and the negative electrode, or can be attached to the surface of the positive electrode or the negative electrode.

[0080] In some embodiments, the separator is a solid-state electrolyte. The solid-state electrolyte is disposed between the positive electrode and the negative electrode, and functions to transport ions and separate the positive electrode and the negative electrode.

[0081] In some embodiments, the electrode assembly is a roll structure. The positive electrode sheet and the negative electrode sheet are wound to form the roll structure.

[0082] In some embodiments, the electrode assembly is a stack structure.

[0083] In some embodiments, the battery cell can include a shell. The shell is used to encapsulate components such as the electrode assembly and the electrolyte. The shell can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell), or an aluminum-plastic film, etc.

[0084] In some embodiments, the shell includes an end cap and a shell body, the shell body is provided with an opening, and the end cap closes the opening to form a sealed space for accommodating the electrode assembly and the electrolyte and the like. The shell body can be provided with one or more openings. The end cap can also be provided with one or more openings.

[0085] In some embodiments, at least one electrode terminal is provided on the shell, and the electrode terminal is electrically connected to the tab of the electrode assembly. The electrode terminal can be directly connected to the tab or indirectly connected to the tab through a current collector. The electrode terminal can be provided on the end cap or on the shell body.

[0086] In some embodiments, an explosion-proof valve is provided on the shell. The explosion-proof valve is used to release the internal pressure of the battery cell.

[0087] In the related art, the outer surface of the shell of the cold columnar battery cell is usually a flat surface. After the battery cell is assembled into a battery, the heat generated by the battery cell during operation is dissipated through the flat surface of the battery cell. The heat dissipation efficiency of the battery cell is low, which easily causes the risk of thermal runaway of the battery cell due to excessive temperature rise. Therefore, the reliability of the battery cell is seriously affected.

[0088] Therefore, the embodiments of the present application provide a battery cell. The battery cell includes a shell and an electrode terminal. The shell has two first walls opposite in a first direction and two second walls opposite in a second direction. The first walls connect the two second walls. At least one of the first walls includes a protruding portion protruding towards the outside of the shell. The electrode terminal is arranged at the end of the shell in a third direction. The first direction, the second direction, and the third direction are perpendicular to each other.

[0089] The battery cell provided by the present application has the following advantages. The first wall of the shell is provided with a protruding portion, and the protruding portion is arranged to protrude towards the outside of the shell. During the operation of the battery cell, heat can be dissipated through the first wall, which is beneficial to increase the heat dissipation area of the battery cell. After the battery cell is assembled into a battery, the gap between the first walls of two adjacent battery cells is increased, which is beneficial to further improve the heat dissipation efficiency of the battery cell. Therefore, the battery cell provided by the embodiments of the present application is beneficial to improve the heat dissipation efficiency of the battery cell, reduce the temperature rise rate and the risk of thermal runaway of the battery cell, and further improve the reliability of the battery cell.

[0090] The technical solutions described in the embodiments of the present application are applicable to battery cells, batteries using battery cells, and electric devices including batteries.

[0091] The battery disclosed in the embodiments of the present application can be used in, but is not limited to, an electric device such as a vehicle, a ship or an aircraft. The power supply system of the electric device can be composed of the battery disclosed in the present application.

[0092] The embodiments of the present application provide an electric device using a battery as a power supply. The electric device can be, but is not limited to, a mobile phone, a tablet computer, a notebook computer, an electric toy, an electric tool, an electric bicycle, an electric motorcycle, an electric vehicle, a ship, a spacecraft and the like. The electric toy can include a fixed or mobile electric toy, such as a game console, an electric vehicle toy, an electric ship toy and an electric aircraft toy. The spacecraft can include an airplane, a rocket, a space shuttle and a spacecraft.

[0093] The following embodiments are described with reference to a vehicle 1 as an electric device in an embodiment of the present application for convenience of description.

[0094] Referring to FIG. 1, FIG. 1 is a structural schematic diagram of a vehicle provided by some embodiments of the present application. The vehicle 1 can be a fuel automobile, a gas automobile or a new energy automobile. The new energy automobile can be a pure electric vehicle, a hybrid electric vehicle or a range extended electric vehicle. The vehicle 1 is internally provided with a battery 10. The battery 10 can be arranged at the bottom, the head or the tail of the vehicle 1. The battery 10 can be used for power supply of the vehicle 1. For example, the battery 10 can be used as an operating power supply of the vehicle 1, and is used for power supply of the circuit system of the vehicle 1, such as power supply for starting, navigation and operation of the vehicle 1.

[0095] The vehicle 1 can further include a controller 1b and a motor 1a. The controller 1b is used to control the battery 10 to supply power to the motor 1a, such as power supply for starting, navigation and driving of the vehicle 1.

[0096] In some embodiments of the present application, the battery 10 can not only be used as an operating power supply of the vehicle 1, but also be used as a driving power supply of the vehicle 1, to replace or partially replace fuel or natural gas to provide driving power for the vehicle 1.

[0097] Please refer to FIG. 2 and FIG. 3, FIG. 2 is an exploded view of the battery 10 provided by some embodiments of the present application, and FIG. 3 is a structural schematic view of the battery module 20 in the battery 10 provided by the embodiments of the present application. The battery 10 comprises a box body 11 and a battery cell 30, and the battery cell 30 is contained in the box body 11. Among them, the box body 11 is used to provide a containing space for the battery cell, and the box body 11 can adopt various structures. In some embodiments, the box body 11 can comprise a first sub-box body 111 and a second sub-box body 112, the first sub-box body 111 and the second sub-box body 112 are mutually covered, and the first sub-box body 111 and the second sub-box body 112 jointly define a containing space for containing the battery cell 30. The second sub-box body 112 can be a hollow structure with one end open, and the first sub-box body 111 can be a plate-shaped structure, which is covered on the open side of the second sub-box body 112 to jointly define the containing space with the second sub-box body 112; the first sub-box body 111 and the second sub-box body 112 can also be hollow structures with one side open, and the open side of the first sub-box body 111 is covered on the open side of the second sub-box body 112.

[0098] In the battery 10, the battery cell 30 can be multiple, and the multiple battery cells 30 can be connected in series, in parallel or in a mixed manner. The mixed connection means that there are both series connection and parallel connection among the multiple battery cells 30. The multiple battery cells 30 can be directly connected in series, in parallel or in a mixed manner, and then the whole of the multiple battery cells 30 is contained in the box body 11; of course, the battery 10 can also be that the multiple battery cells 30 are first connected in series, in parallel or in a mixed manner to form a battery module 20, and then the multiple battery modules 20 are connected in series, in parallel or in a mixed manner to form a whole, which is contained in the box body 11. The battery 10 can also comprise other structures, for example, the battery 10 can also comprise a current combing component for realizing the electrical connection among the multiple battery cells 30.

[0099] Among them, the battery cell 30 can be a secondary battery or a primary battery; the battery cell 30 can also be a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited thereto.

[0100] Please refer to FIG. 4, which is an exploded view of the battery cell 30 provided by some embodiments of the present application. As shown in FIG. 4, the battery cell 30 comprises an outer shell 31, an electrode assembly 32 and an electrode terminal 33. The outer shell 31 comprises a shell body 311 and an end cover 312, the shell body 311 has an opening, and the end cover 312 closes the opening to isolate the internal environment of the battery cell 30 from the external environment.

[0101] The shell 311 is a component for fitting the end cover 312 to form an internal environment of the battery cell 30, wherein the formed internal environment can be used to accommodate the electrode assembly 32, electrolyte and other components. The shell 311 and the end cover 312 can be independent components. The shell 311 can be of various shapes and sizes. Specifically, the shape of the shell 311 can be determined according to the specific shape and size of the electrode assembly 32. The material of the shell 311 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0102] The end cover 312 refers to a component that covers the opening of the shell 311 to isolate the internal environment of the battery cell 30 from the external environment. Without limitation, the shape of the end cover 312 can be adapted to the shape of the shell 311 to fit the shell 311. Optionally, the end cover 312 can be made of a material with certain hardness and strength (such as aluminum alloy), so that the end cover 312 is not easily deformed when subjected to extrusion collision, so that the battery cell 30 can have higher structural strength, and the reliability can also be improved. The end cover 312 can be provided with functional components such as the electrode terminal 33. The electrode terminal 33 can be used to electrically connect with the electrode assembly 32 for outputting or inputting the electrical energy of the battery cell 30. The material of the end cover 312 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which are not specially limited in the embodiments of the present application. In some embodiments, an insulating structure can also be provided on the inner side of the end cover 312, which can be used to isolate the electrical connection components in the shell 311 from the end cover 312 to reduce the risk of short circuit. Exemplarily, the insulating structure can be plastic, rubber, etc.

[0103] The electrode assembly 32 is a component in which electrochemical reactions occur in the battery cell 30. One or more electrode assemblies 32 can be contained in the shell 311. The electrode assembly 32 is mainly formed by winding or stacking the positive electrode sheet and the negative electrode sheet, and generally has a separator film between the positive electrode sheet and the negative electrode sheet, which is used to separate the positive electrode sheet and the negative electrode sheet to avoid internal short circuit of the positive electrode sheet and the negative electrode sheet. The positive electrode sheet and the negative electrode sheet have a part of active material constituting the electrode body of the electrode assembly, and the parts of the positive electrode sheet and the negative electrode sheet without active material each constitute a tab. The positive tab and the negative tab can be located together at one end of the electrode body or respectively at two ends of the electrode body. In the charging and discharging process of the battery cell 30, the positive active material and the negative active material react with the electrolyte, and the tabs are connected to the electrode terminal 33 to form a current loop.

[0104] In a first aspect, as shown in FIG. 4, FIG. 5 and FIG. 6, the embodiments of the present application provide a battery cell 30, the battery cell 30 comprising a housing 31 and an electrode terminal 33, the housing 31 having two first walls 40 opposite along a first direction X and two second walls 50 opposite along a second direction Y, the two first walls 40 connecting the two second walls 50, a maximum distance between the two first walls 40 along the first direction X being less than a maximum distance between the two second walls 50 along the second direction Y, at least one first wall 40 comprising a protrusion 41 protruding towards an outside of the housing 31. The electrode terminal 33 is arranged at an end of the housing 31 along a third direction Z, the first direction X, the second direction Y and the third direction Z being perpendicular to each other.

[0105] The housing 31 has the two first walls 40 and the two second walls 50, the first walls 40 and the second walls 50 being adjacent and intersecting with the wall part where the electrode terminal 33 is arranged, in other words, the electrode terminal 33 is arranged at a wall part of the battery cell 30 other than the first walls 40 and the second walls 50.

[0106] The at least one first wall 40 comprises the protrusion 41, which is optional, either one of the two first walls 40 can comprise the protrusion 41, or both of the two first walls 40 can comprise the protrusion 41. When both of the two first walls 40 comprise the protrusion 41, the protrusions 41 of the different first walls 40 can have the same protruding size or structure type, or the protrusions 41 of the two first walls 40 can have different protruding sizes or structure types.

[0107] The protrusion 41 can have an arc shape, the protrusion 41 can have a prismatic shape, or the protrusion 41 can have other irregular shapes.

[0108] The protrusion 41 can be obtained by bending or folding the first wall 40, or the protrusion 41 can be obtained by adding material to the first wall 40, which can be selected according to requirements.

[0109] The first wall 40 can have a part as the protrusion 41, or the entire first wall 40 can be the protrusion 41. The first wall 40 can have one, two or more protrusions 41, the protrusion 41 can be located at a middle part of the first wall 40, or the protrusion 41 can be located at both sides of the first wall 40 along the second direction Y.

[0110] Since the battery monomer 30 has the protruding part 41, after the battery monomers 30 are arranged in groups along the first direction X, the first walls 40 of adjacent battery monomers 30 are adjacent, and since at least one first wall 40 of the battery monomer 30 has the protruding part 41, a larger gap can be formed between the first wall 40 with the protruding part 41 and the first wall 40 of the adjacent battery monomer 30, which is beneficial to improve the heat dissipation area and heat dissipation efficiency of the battery monomer 30 during operation.

[0111] The maximum distance between the two first walls 40 along the first direction X is smaller than the maximum distance between the two second walls 50 along the second direction Y, that is, the area of the normal projection of the first wall 40 in the plane where the second direction Y and the third direction Z are located is larger than the area of the normal projection of the second wall 50 in the plane where the first direction X and the third direction Z are located. That is, the first wall 40 is a wall part that occupies a larger area of the outer shell 31, while the second wall 50 is a wall part that occupies a smaller area of the outer shell 31. After the battery monomers 30 are arranged in groups, it is beneficial to further increase the gap between adjacent battery monomers 30 along the first direction X, and to further improve the heat dissipation efficiency of the battery monomer 30, thereby reducing the risk of thermal runaway of the battery monomer 30.

[0112] In addition, after the battery monomers 30 are arranged in groups along the first direction X, a heat insulation member 60 is usually arranged between adjacent battery monomers 30 to block the heat transfer between the battery monomers 30. Since the heat dissipation area and heat dissipation efficiency of the battery monomer 30 are increased, the heat insulation requirement of the heat insulation member 60 between adjacent battery monomers 30 is reduced, the thickness of the heat insulation member 60 can be reduced, and the space inside the box 11 of the battery 10 can be saved to arrange more battery monomers 30, which is beneficial to improve the energy density of the battery 10.

[0113] The battery monomer 30 provided in the application has the protruding part 41 on the first wall 40 of the outer shell 31, and the protruding part 41 is arranged to protrude outward from the outer shell 31, which is beneficial to improve the heat dissipation area of the battery monomer 30 during operation, and the gap between the first walls 40 of adjacent battery monomers 30 is increased after the battery monomers 30 are arranged in groups, which is beneficial to further improve the heat dissipation efficiency of the battery monomer 30. Therefore, the battery monomer 30 provided in the embodiments of the application is beneficial to improve the heat dissipation efficiency of the battery monomer 30, reduce the temperature rise rate of the battery monomer 30, and reduce the risk of thermal runaway of the battery monomer 30, thereby improving the reliability of the battery monomer 30.

[0114] In some embodiments, please continue to refer to FIG. 5, both of the first walls 40 have the protruding part 41.

[0115] The two first walls 40 of the battery cell 30 opposite to each other along the first direction X are provided with the protrusions 41, which are beneficial to further increase the heat dissipation area of the battery cell 30, and after the battery cells 30 are grouped, the gaps between the battery cell 30 and the adjacent battery cells 30 on both sides along the first direction X are increased, which is beneficial to further improve the heat dissipation efficiency of the battery cell 30 and further reduce the risk of thermal runaway of the battery cell 30. Moreover, after the battery cells 30 are grouped into the battery cell 30, the heat insulation requirement of the heat insulation member 60 between the battery cells 30 is further reduced, which is beneficial to reduce the thickness of the heat insulation member 60 and further improve the energy density of the battery 10.

[0116] In some embodiments, as shown in FIG. 5, the protrusions 41 are arc-shaped and protrude towards the outside of the shell 31.

[0117] Optionally, the protrusions 41 can be circular-arc-shaped, or the protrusions can be non-circular-arc-shaped. Exemplarily, a part of the first wall 40 can be provided as a whole in a cylindrical shape.

[0118] The protrusions 41 are arc-shaped, which can be formed by a bending process or by pressurizing the inside of the battery cell 30 after the preparation of the battery cell 30 is completed.

[0119] The protrusions 41 are arc-shaped, which is beneficial to the manufacturing and forming of the first wall 40 and is beneficial to simplify the preparation process of the battery cell 30. Moreover, the contact between the arc-shaped protrusions 41 and the adjacent battery cells 30 can be linear contact, which is beneficial to reduce the contactable area of the adjacent battery cells 30 and improve the gap between the battery cells 30 adjacent along the first direction X, and is beneficial to further improve the heat dissipation efficiency of the battery cell 30.

[0120] In some embodiments, as shown in FIG. 6, the battery cell 30 further comprises an electrode assembly 32, the electrode assembly 32 is accommodated in the shell 31, and the electrode assembly 32 has a first surface 321 provided towards the protrusions 41, and the first surface 321 is protrudingly provided towards the protrusions 41.

[0121] The electrode assembly 32 has the first surface 321, and the first surface 321 is protrudingly provided towards the protrusions 41, so that at least part of the electrode assembly 32 is protrudingly provided towards the protrusions 41.

[0122] Exemplarily, in the case that the first wall 40 is a part of a whole in an outwardly protruding cylindrical shape, the first surface 321 of the electrode assembly 32 can be conformally provided with the first wall 40, that is, the shortest distance from any position of the electrode assembly 32 to the first wall 40 is equal.

[0123] The first wall 40 of the electrode assembly 32 is protruded towards the protrusion 41, which is conducive to increasing the space occupied by the electrode assembly 32 in the inside of the shell 31, and thus is conducive to increasing the group margin of the battery monomer 30, reducing the risk of looseness of the electrode assembly 32, and improving the energy density of the battery monomer 30.

[0124] In some embodiments, as shown in FIGS. 5, 6, 7 and 8, the second wall 50 has a size w along the first direction X, and the protrusion 41 has a first cross section perpendicular to the third direction Z, and a maximum size h of a projection of the first cross section on a plane parallel to the first direction X and the third direction Z along the first direction X, h / w≤0.5.

[0125] The maximum size h of the projection of the first cross section on the plane parallel to the first direction X and the third direction Z can be the protruding distance of the protrusion 41.

[0126] Optionally, h / w can be 0.1, 0.2, 0.3, 0.4 or 0.5, etc.

[0127] It can be understood that the larger the value of h is, the more conducive to improving the heat dissipation efficiency of the battery monomer 30, and the smaller the value of h is, the more conducive to improving the energy density of the battery monomer 30.

[0128] The inventor found through systematic analysis and long-term practice that setting h / w≤0.5 can improve the heat dissipation efficiency of the battery monomer 30, and at the same time, the battery monomer 30 has a high energy density, so that the battery monomer 30 can achieve a better balance between heat dissipation efficiency and energy density.

[0129] It should be noted that when both the first walls 40 of the battery monomer 30 have protrusions 41, the maximum sizes of the projections of the first cross sections of the two protrusions 41 on the plane parallel to the first direction X and the third direction Z along the first direction X can be h1 and h2 respectively, and in this case, (h1+h2) / w≤1 should be met.

[0130] In some embodiments, 0.005≤h / w≤0.125.

[0131] 0.005≤h / w≤0.125, then 0.01≤(h1+h2) / w≤0.25.

[0132] Optionally, h / w can be 0.005, 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, 0.055, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12 or 0.125, etc.

[0133] The inventor further found through further systematic analysis and long-term practice that, by setting 0.01≤h / w≤0.125, the battery monomer 30 can further have a higher energy density on the premise of further improving the heat dissipation efficiency of the battery monomer 30, so as to further balance the heat dissipation efficiency and the energy density of the battery monomer 30.

[0134] In some embodiments, as shown in FIGS. 7 and 8, the at least one first wall 40 further comprises a flat portion 42, which is perpendicular to the first direction X and adjacent to the protruding portion 41.

[0135] The flat portion 42 can be a relatively flat part of the first wall 40. Optionally, the flat portion 42 can be arranged on both sides of the protruding portion 41, or the protruding portion 41 can be arranged on both sides of the flat portion 42, or the first wall 40 can have a flat portion 42 and a protruding portion 41, and the flat portion 42 and the protruding portion 41 are respectively adjacent to the second walls 50 on both sides.

[0136] The arrangement of the first wall 40 including the flat portion 42 is conducive to increasing the space inside the shell 31 of the battery monomer 30, increasing the space occupancy rate of the electrode assembly 32 inside the battery monomer 30, and further improving the energy density of the battery monomer 30.

[0137] In some embodiments, as shown in FIG. 7, the flat portion 42 is arranged on both sides of the protruding portion 41 along the second direction Y and is respectively adjacent to the second wall 50.

[0138] In this way, after the battery monomer 30 is arranged along the first direction X, there is a larger space between the flat portions 42 on both sides of the opposite protruding portions 41 between adjacent battery monomers 30, which is conducive to further improving the energy density of the battery monomer 30.

[0139] In some embodiments, as shown in FIG. 8, the protruding portion 41 is arranged on both sides of the flat portion 42 along the second direction Y and is respectively adjacent to the second wall 50.

[0140] The arrangement of the protruding portion 41 on both sides of the flat portion 42 along the second direction Y forms a larger gap between the protruding portions 41 on both sides of the first wall 40 and the first wall 40 of the adjacent battery monomer 30 after the battery monomer 30 is arranged along the first direction X. In this way, it is still conducive to improving the heat dissipation efficiency of the battery monomer 30.

[0141] In some embodiments, as shown in FIGS. 8 and 9, the size of the flat portion 42 along the second direction Y is L1, and the size of the shell 31 along the second direction Y is L, and L1 / L≤0.5.

[0142] Optionally, L1 / L can be 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, or 0.5, etc.

[0143] After the battery cells 30 are grouped, the battery cells 30 can be in contact with the battery cells 30 adjacent along the first direction X through the flat portions 42. The inventors have found through systematic analysis and long-term practice that setting L1 / L≤0.5 is conducive to reducing the area of mutual contact of two battery cells 30 adjacent along the first direction X, and further conducive to improving the heat dissipation efficiency of the battery cells 30.

[0144] In a second aspect, as shown in FIG. 10, the present application provides a battery 10, which includes the heat insulation member 60 and the battery cell 30 provided by any of the above embodiments. The plurality of battery cells 30 are arranged at least along the first direction X, and the heat insulation member 60 is arranged between the first walls 40 of two battery cells 30 adjacent along the first direction X.

[0145] The plurality of battery cells 30 are arranged at least along the first direction X. Optionally, the plurality of battery cells 30 can be arranged only along the first direction X, or the plurality of battery cells 30 can be arranged along the first direction X and the second direction Y.

[0146] The heat insulation member 60 is arranged between the first walls 40 of two battery cells 30 adjacent along the first direction X, so that the heat insulation member 60 can abut the first walls 40 of the two battery cells 30, respectively. Optionally, the heat insulation member 60 can be in the form of a heat insulation pad, or the heat insulation member 60 can be in the form of a heat insulation glue 61, i.e., after fluid glue is added between the two adjacent battery cells 30, the fluid glue solidifies to form the heat insulation glue 61.

[0147] Optionally, the material of the heat insulation member 60 can be a special insulating material (polysulfone, polyarylate, polytetrafluoroethylene, polyimide, etc.), a general insulating material (polystyrene, polypropylene, polyethylene, etc.), a thermosetting plastic (polyurethane, furan, allyl ester, phenolic, unsaturated polyester, silicone, aminoplast, etc.), or an engineering plastic (polycarbonate, thermoplastic polyester, nylon, modified polyphenylene ether, thermoplastic polyester, etc.), etc.

[0148] The heat insulation member 60 can only have a heat insulation effect, or the heat insulation member 60 can be provided with a vibration buffering effect to reduce the vibration or impact borne by the battery cells 30.

[0149] The battery 10 provided by the embodiments of the present application, since the battery monomer 30 provided by any of the above embodiments is adopted, the heat dissipation efficiency of the battery monomer 30 is improved, the temperature rise of the battery 10 is reduced, and the risk of thermal runaway of the battery 10 is reduced during the working process of the battery 10. Moreover, due to the increase of the heat dissipation efficiency of the battery monomer 30, the heat insulation requirement of the heat insulation member 60 is reduced, so that the material requirement and the thickness requirement of the heat insulation member 60 of the battery 10 are reduced, which is beneficial to reduce the overall space occupied by the heat insulation member 60 in the battery 10 and improve the energy density of the battery 10.

[0150] In some embodiments, as shown in FIG. 10, the heat insulation member 60 includes the heat insulation glue 61, and the heat insulation glue 61 is filled between the first walls 40 of two battery monomers 30 adjacent in the first direction X.

[0151] Specifically, after the battery monomer 30 is arranged in the first direction X, the fluid glue can be added between two battery monomers 30 adjacent in the first direction X, and the fluid glue is formed into the heat insulation glue 61 after curing and shaping, and is respectively bonded and connected with the two battery monomers 30.

[0152] The heat insulation member 60 including the heat insulation glue 61 can be set according to the specific shape of the first wall 40, and the thickness of the heat insulation glue 61 corresponding to different parts of the first wall 40 can be more flexibly set, which is beneficial to reduce the process difficulty of the assembly process of the battery 10.

[0153] In a third aspect, the embodiments of the present application provide a power consumption device, which includes the battery monomer 30 provided by any of the above embodiments or the battery 10 provided by the above embodiments, and the battery 10 is used to provide electric energy.

[0154] The power consumption device provided by the embodiments of the present application has the same technical effects as the battery 10 or the battery monomer 30 provided by any of the above embodiments, and details are not repeated here.

[0155] In some embodiments, as shown in FIGS. 4-9, the battery cell 30 includes a shell 31, an electrode assembly 32, and an electrode terminal 33. The shell 31 has two first walls 40 opposite along a first direction X and two second walls 50 opposite along a second direction Y, the first walls 40 connecting the two second walls 50, the two first walls 40 including protrusions 41, the protrusions 41 being arc-shaped and protruding towards the outside of the shell 31. The electrode terminal 33 is arranged at an end of the shell 31 along a third direction Z, the first direction X, the second direction Y, and the third direction Z being perpendicular to each other. A maximum distance between the two first walls 40 along the first direction X is less than a maximum distance between the two second walls 50 along the second direction Y. The electrode assembly 32 is accommodated in the shell 31, and the electrode assembly 32 has a first surface 321 arranged towards the protrusions 41, the first surface 321 protruding towards the protrusions 41. A dimension of the second wall 50 along the first direction X is w, and the protrusion 41 has a first cross section perpendicular to the third direction Z, a maximum dimension of a normal projection of the first cross section along the first direction X in a plane parallel to the first direction X and the third direction Z is h, and h / w≤0.5.

[0156] The battery cell 30 provided by the present application has the first wall 40 of the shell 31 with the protrusions 41, and the protrusions 41 protrude towards the outside of the shell 31, so that heat can be dissipated through the first wall 40 during the operation of the battery cell 30, which is beneficial to increase the heat dissipation area of the battery cell 30, and the gap between the first walls 40 of two adjacent battery cells 30 is increased after the battery cells 30 are grouped, which is beneficial to further improve the heat dissipation efficiency of the battery cell 30. Therefore, the battery cell 30 provided by the embodiments of the present application is beneficial to improve the heat dissipation efficiency of the battery cell 30, reduce the temperature rise rate of the battery cell 30, and reduce the risk of thermal runaway of the battery cell 30, thereby improving the reliability of the battery cell 30.

[0157] Although the present application has been described with reference to the preferred embodiments, various modifications can be made to the present application without departing from the scope of the present application, and equivalent components can be substituted therefor. In particular, the technical features mentioned in each embodiment can be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, comprising: a housing having two first walls opposite along a first direction and two second walls opposite along a second direction, the first walls connecting the second walls, a maximum distance between the first walls along the first direction being less than a maximum distance between the second walls along the second direction, at least one of the first walls comprising a protrusion protruding toward an outside of the housing; an electrode terminal provided at an end of the housing along a third direction, the first direction, the second direction and the third direction being perpendicular to each other.

2. The battery cell according to claim 1, wherein: Both of the first walls comprise the protrusion.

3. The battery cell of claim 1 or 2, wherein, The protrusion is arc-shaped and protrudes toward the outside of the housing.

4. The battery cell of claim 3, wherein, The battery cell further comprises an electrode assembly accommodated in the housing, the electrode assembly having a first surface provided toward the protrusion, the first surface protruding toward the protrusion.

5. The battery cell of claim 3 or 4, wherein, A dimension of the second wall along the first direction is w, the protrusion has a first cross section perpendicular to the third direction, a maximum dimension of a projection of the first cross section on a plane parallel to the first direction and the third direction along the first direction is h, and h / w≤0.

5.

6. The battery cell of claim 5, wherein, 0.005≤h / w≤0.

125.

7. The battery cell of any one of claims 1 to 6, wherein, At least one of the first walls further comprises a flat portion perpendicular to the first direction and adjacent to the protrusion.

8. The battery cell of claim 7, wherein, The flat portion is provided on both sides of the protrusion along the second direction and adjacent to the second walls, respectively.

9. The battery cell of claim 7 or 8, wherein, The protrusion is provided on both sides of the flat portion along the second direction and adjacent to the second walls, respectively.

10. The battery cell of claim 9, wherein, A dimension of the flat portion along the second direction is L1, a dimension of the housing along the second direction is L, and L1 / L≤0.

5. 11.A battery, comprising: a plurality of battery cells according to any one of claims 1 to 10 arranged at least along the first direction; a thermal insulation member provided between the first walls of two battery cells adjacent along the first direction.

12. The battery of claim 11, wherein, The thermal insulation member comprises thermal insulation glue filled between the first walls of two battery cells adjacent along the first direction.

13. An electrical device, comprising: A battery according to claim 11 or 12, or a battery cell according to any one of claims 1 to 10, for providing electrical energy.

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