Battery cell, battery and electric apparatus

Abstract

A battery cell (2), a battery (100) and an electric apparatus. The battery cell (2) comprises a casing (21), electrode terminals (22) and an electrode assembly (23), wherein the electrode terminals (22) are disposed on the casing (21); the electrode assembly (23) is accommodated in the casing (21), a thinned portion (232) of the electrode assembly (23) is connected to an end portion of a main body portion (231) in a first direction (Y), and tabs (233) are led out from the thinned portion (232) and are connected to the electrode terminals (22); and the casing (21) comprises a wall body (213) surrounding the electrode assembly (23), the wall body (213) comprising a first portion (2113) and a second portion (2114) that are connected to each other, the first portion (2113) being located on the outer side of the thinned portion (232) in the radial direction of the electrode assembly (23), and the thickness of the first portion (2113) being greater than that of the second portion (2114). The thickness of the first portion (2113) of the wall body (213) surrounding the electrode assembly (12) is greater than the thickness of the second portion (2114), and the first portion (2113) is located on the outer side of the thinned portion (232) in the radial direction of the electrode assembly (23), such that during the expansion of the electrode assembly (23), the first portion (2113) can provide a relatively large binding force to restrict the expansion of the electrode assembly (23), and the increase or uneven distribution of gaps between electrode sheet layers in the electrode assembly (23) can be alleviated, which is conducive to prolonging the service life of the battery cell (2).

Description

A battery cell, a battery, and an electrical device.

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202420853059.4, filed on April 23, 2024, entitled “A Battery Cell, a Battery and an Electrical Device”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of battery technology, and in particular to a battery cell, a battery, and an electrical device. Background Technology

[0004] Batteries have advantages such as high energy density and high power density, and are widely used in electronic devices and transportation, such as mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships and power tools.

[0005] As the application scope of batteries continues to expand, how to extend the service life of batteries is receiving increasing attention from those skilled in the art.

[0006] Summary of the Invention

[0007] In view of the above problems, this application provides a battery cell, a battery, and an electrical device, wherein the battery cell has a long service life.

[0008] In a first aspect, some embodiments of this application provide a battery cell including a housing, electrode terminals, and an electrode assembly. The electrode terminals are disposed in the housing, and the electrode assembly is housed within the housing. A thinned portion of the electrode assembly is connected to an end of a main body in a first direction. An electrode tab extends from the thinned portion and is connected to the electrode terminal. The housing includes a wall surrounding the electrode assembly. The wall includes a first part and a second part connected to each other. The first part is located radially outside the thinned portion of the electrode assembly, and the thickness of the first part is greater than the thickness of the second part.

[0009] In the above structure, since the thickness of the first part in the wall surrounding the electrode assembly is greater than the thickness of the second part and the first part is located on the radial side of the thinned part of the electrode assembly, the first part can provide a larger binding force to limit the expansion of the electrode assembly during the expansion process. This can improve the increase or uneven distribution of the interlayer gap of the electrode assembly, which is beneficial to extending the service life of the battery cell.

[0010] According to some embodiments of the present application, the projection of the first part of the battery cell along the radial direction of the electrode assembly coincides with the projection of at least a portion of the thinned part, such that at least a portion of the first part corresponds to the thinned part in the radial direction of the electrode assembly. This allows the first part to better enhance the structural strength of the wall in the corresponding area outside the thinned part, and to better restrain the expansion of the thinned part during the expansion of the electrode assembly. This is beneficial for reducing the increase or uneven distribution of the interlayer gap of the electrode sheet in the thinned part of the electrode assembly and extending the service life of the battery cell.

[0011] According to some embodiments of this application, the battery cell has an integrally formed wall structure, which allows the first part and the second part to be manufactured synchronously as a whole. This not only makes the processing and manufacturing of the wall convenient, but also gives the overall structure of the wall good strength.

[0012] According to some embodiments of this application, the battery cell includes a main wall structure and a reinforcing structure. The main wall structure surrounds the electrode assembly, and the reinforcing structure is connected to the surface of the main wall structure opposite to the electrode assembly to form a first part. Forming the first part by connecting the reinforcing structure to the surface of the main wall structure opposite to the electrode assembly reduces the difficulty and ease of forming the first part.

[0013] According to some embodiments of this application, the battery cell includes a first wall and a second wall disposed opposite to each other. The first wall and the second wall are each provided with a first part, so that the first wall and the second wall disposed opposite to each other are provided with a first part that can enhance the structural strength. This allows the first wall and the second wall to relatively bind the electrode assembly from both sides of the electrode assembly, providing better binding force for the expansion of the electrode assembly and better improving the increase or uneven distribution of the gap between the electrode layers in the electrode assembly.

[0014] According to some embodiments of the present application, in a battery cell, the dimension of the first portion is L1, and the dimension of the thinned portion is L2, along a first direction. The ratio of the size of the first part in the first direction to the size of the thinned part in the first direction is within a suitable range, so that the first part not only has a sufficient size in the first direction to provide sufficient binding force, but also reduces the size of the first part and reduces material waste.

[0015] The battery cell provided according to some embodiments of this application This ensures that the first part has sufficient dimensions for the corresponding thinning part in the first direction, providing sufficient binding force, while also reducing material waste caused by setting too many first parts.

[0016] According to some embodiments of this application, the battery cell has a first portion with a dimension of L1 and a casing with a dimension of L3 along a first direction. This ensures that the ratio of the size of the first part in the first direction to the size of the housing in the first direction is within a suitable range. This not only allows the first part to occupy a sufficient size of the housing in the first direction, providing sufficient structural reinforcement for the housing, but also reduces material waste due to excessive placement of the first part assembly.

[0017] The battery cell provided according to some embodiments of this application This ensures that the first part occupies a sufficient size in the outer shell in the first direction to provide sufficient binding force, while also reducing material waste caused by excessive placement of the first part.

[0018] According to some embodiments of this application, the thickness of the first part of the battery cell along the radial direction of the electrode assembly is W1, and the thickness of the battery cell is W2. This ensures that the ratio of the thickness of the first part in the radial direction to the thickness of the electrode assembly is within a suitable range. This not only gives the first part sufficient structural strength to resist the expansion of the electrode assembly, but also helps to improve the resistance of the first part in the radial direction to the expansion force of the electrode assembly, and helps to improve the increase or uneven distribution of the interlayer gap of the electrode in the electrode assembly. It also helps to reduce the waste of material caused by the excessive size of the first part in the radial direction of the electrode assembly.

[0019] The battery cell provided according to some embodiments of this application This allows the first part to have a suitable thickness relative to the electrode assembly in the radial direction. This not only helps to improve the resistance of the first part to the expansion force of the electrode assembly in the radial direction, but also helps to reduce the material waste caused by the first part being too large in the radial direction of the electrode assembly.

[0020] According to some embodiments of the present application, the surface of the battery cell facing the electrode assembly of the first part is flush with the surface of the second part facing the electrode assembly, so that the inner surface of the cavity surrounded by the outer shell is flat, and the inner surface of the cavity accommodating the electrode assembly is less likely to have steps, which helps to reduce the possibility of the electrode assembly being damaged by scratches.

[0021] According to some embodiments of this application, the battery cell includes a housing and an end cap. The housing forms a cavity with an opening, the opening is oriented along a first direction, an electrode assembly is located in the cavity, the end cap covers the opening, electrode terminals are disposed on the end cap, and both a first part and a second part are located in the housing.

[0022] According to some embodiments of the present application, the battery cell is connected to the opening, which not only allows the first part to better cover the thinned part, but also helps to improve the binding effect of the first part on the expansion of the thinned part, improve the increase or uneven distribution of the interlayer gap of the electrode in the thinned part, and also improves the firmness of the end cap connection on the opening.

[0023] Secondly, some embodiments of this application also provide a battery, which includes the battery cell provided by any of the foregoing technical solutions.

[0024] Thirdly, some embodiments of this application also provide an electrical device, which includes the battery provided by the aforementioned technical solution, and the battery is used to provide electrical energy.

[0025] The technical solutions provided by the embodiments of this disclosure have at least the following beneficial effects:

[0026] Some embodiments of this application provide a battery cell including a housing, electrode terminals, and an electrode assembly. The electrode terminals are disposed in the housing, and the electrode assembly is housed within the housing. A thinned portion of the electrode assembly is connected to the end of a main body in a first direction. A tab extends from the thinned portion and connects to the electrode terminals. The housing includes a wall surrounding the electrode assembly, and the wall includes a first part and a second part connected to each other. The first part is located radially outside the thinned portion of the electrode assembly, and the thickness of the first part is greater than the thickness of the second part. In the above structure, because the thickness of the first part in the wall surrounding the electrode assembly is greater than the thickness of the second part, and the first part is located radially outside the thinned portion of the electrode assembly, the first part can provide a greater binding force to limit the expansion of the electrode assembly during expansion. This can improve the increase or uneven distribution of the interlayer gaps in the electrode assembly, which is beneficial to extending the service life of the battery cell.

[0027] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below. Attached Figure Description

[0028] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0029] Figure 1 is a schematic diagram of the vehicle structure provided in some embodiments of this application;

[0030] Figure 2 is an exploded view of a battery provided in some embodiments of this application;

[0031] Figure 3 is a split view of a battery cell provided in some embodiments of this application;

[0032] Figure 4 is a cross-sectional view of a battery cell provided in some embodiments of this application;

[0033] Figure 5 is a cross-sectional view of a portion of the battery cell structure provided in some other embodiments of this application.

[0034] In the attached diagram:

[0035] 10. Housing; 101. First housing; 102. Second housing; 2. Battery cell; 21. Outer shell; 211. Housing; 2111. Opening; 2112. Cavity; 2113. First part; 2114. Second part; 212. End cap; 213. Wall; 2131. Main wall structure; 2132. Reinforcing structure; 214. First wall; 215. Second wall; 216. Third wall; 217. Fourth wall; 22. Electrode terminal; 23. Electrode assembly; 231. Main body; 232. Thinned part; 233. Tab; 1000. Vehicle; 100. Battery; 200. Controller; 300. Motor; Y, First direction. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0037] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0038] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0039] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0040] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0041] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0042] In the embodiments of this application, "parallel" includes not only the case of absolute parallelism, but also the case of approximate parallelism as commonly understood in engineering; similarly, "perpendicular" also includes not only the case of absolute perpendicularity, but also the case of approximate perpendicularity as commonly understood in engineering. For example, if the angle between two directions is 85°-90°, the two directions can be considered perpendicular; if the angle between two directions is 0°-5°, the two directions can be considered parallel.

[0043] In this application, "multiple" means two or more (including two).

[0044] Currently, judging from market trends, the application of batteries is becoming increasingly widespread. Batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace, among other fields.

[0045] The battery mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity.

[0046] A battery cell can be a rechargeable battery cell, which refers to a battery cell that can be recharged after being discharged to activate the active materials and continue to be used.

[0047] Battery cells can be lithium-ion cells, sodium-ion cells, sodium-lithium-ion cells, lithium metal cells, sodium metal cells, lithium-sulfur cells, magnesium-ion cells, nickel-metal hydride cells, nickel-cadmium cells, lead-acid cells, etc.

[0048] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0049] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not impose specific limitations on the type of electrolyte; it can be selected according to requirements. The electrolyte can be liquid, gel, or solid.

[0050] In some embodiments, the liquid electrolyte includes an electrolyte salt and a solvent.

[0051] In some embodiments, the electrolyte salt may be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0052] In some embodiments, the solvent may be selected from at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may 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, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0053] Gel electrolytes consist of a polymer-based electrolyte backbone network combined with an ionic liquid—lithium salt.

[0054] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0055] As an example, polymer solid electrolytes can be polyethers (polyoxyethylene), polysiloxanes, polycarbonates, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0056] As an example, inorganic solid electrolytes can be one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphorus sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0057] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0058] In some embodiments, the electrode assembly is a wound structure. Optionally, the electrode assembly is a cylindrical wound structure.

[0059] In some embodiments, a single battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing may be made of steel, aluminum, plastic (such as polypropylene), composite metal (such as copper-aluminum composite), or aluminum-plastic film, etc.

[0060] As an example, a battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries.

[0061] In some embodiments, the battery can be a battery module, and when there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0062] In some embodiments, the battery can be a battery pack, which includes a housing and individual battery cells, with the individual battery cells or battery modules housed within the housing.

[0063] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0064] In some embodiments, the battery can be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0065] As the application range of batteries expands, people have higher and higher requirements for battery lifespan, and how to extend battery lifespan is attracting increasing attention from those skilled in the art. Currently, battery electrodes typically have a thinning zone near the tab to improve battery performance. However, since batteries usually expand after a period of use, this can increase the gap between the electrode layers in the thinning zone or cause uneven distribution, which can easily lead to poor electrode wetting and increased internal resistance, thereby shortening the battery life.

[0066] To extend the service life of a single battery cell, some embodiments of this application provide a battery cell including a housing, electrode terminals, and an electrode assembly. The electrode terminals are disposed in the housing, and the electrode assembly is housed within the housing. A thinned portion of the electrode assembly is connected to the end of a main body in a first direction. A tab extends from the thinned portion and connects to the electrode terminals. The housing includes a wall surrounding the electrode assembly, and the wall includes a first part and a second part connected to each other. The first part is located radially outside the thinned portion of the electrode assembly, and the thickness of the first part is greater than the thickness of the second part. In the above structure, because the thickness of the first part in the wall surrounding the electrode assembly is greater than the thickness of the second part, and the first part is located radially outside the thinned portion of the electrode assembly, the first part can provide a greater binding force to limit the expansion of the electrode assembly during expansion. This can improve the increase or uneven distribution of the interlayer gaps in the electrode assembly, which is beneficial for extending the service life of the battery cell.

[0067] The battery cell described in this application is applicable to batteries and electrical devices that use batteries. This battery cell can be used, but is not limited to, batteries, and can also be used in products such as vehicles, aircraft, ships, electronic devices, and power tools, thereby improving the reliability of these products.

[0068] Electrical devices can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, among others. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power 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, etc.

[0069] For ease of explanation, the following embodiments will be described using a vehicle as an example of an electrical device according to an embodiment of this application.

[0070] Please refer to Figure 1, which is a structural schematic diagram of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery 100 is disposed inside the vehicle 1000, and the battery 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery 100 can be used to power the vehicle 1000; for example, the battery 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during startup, navigation, and driving.

[0071] In some embodiments of this application, the battery 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0072] Please refer to Figure 2, which is an exploded view of a battery 100 provided in some embodiments of this application. The battery 100 includes a housing 10 and battery cells 2, with the battery cells 2 housed within the housing 10. The housing 10 provides space for the battery cells 2. There can be multiple battery cells 2 in the battery 100, which can be connected in series, parallel, or a combination thereof. A combination thereof means that multiple battery cells 2 are connected in both series and parallel connections. Multiple battery cells 2 can be directly connected in series, parallel, or a combination thereof, and then the entire assembly of the multiple battery cells 2 is housed within the housing 10. Alternatively, the battery 100 can also be composed of multiple battery cells 2 first connected in series, parallel, or a combination thereof to form a battery module, and then multiple battery modules are connected in series, parallel, or a combination thereof to form a whole, which is then housed within the housing 10.

[0073] The housing 10 may include a first housing 101 and a second housing 102, which overlap each other to define a space for accommodating the battery cell 2. The first housing 101 and the second housing 102 may have various shapes, such as cuboids or cylinders. The first housing 101 may be a hollow structure with one open side, and the second housing 102 may also be a hollow structure with one open side. When the open side of the second housing 102 overlaps the open side of the first housing 101, a housing 10 with a storage space is formed.

[0074] The battery 100 may also include other structures, for example, the battery 100 may also include a busbar for realizing electrical connection between multiple battery cells 2.

[0075] Each battery cell 2 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited to these. The battery cell 2 can be cylindrical, flat, cuboid, or other shapes.

[0076] In some embodiments of this application, referring to Figures 3 and 4, the battery cell 2 includes a housing 21, electrode terminals 22, and electrode assembly 23. The electrode terminals 22 are disposed in the housing 21, and the electrode assembly 23 is housed within the housing 21. The electrode assembly 23 includes a main body portion 231, a thinned portion 232, and a tab 233. The thinned portion 232 is connected to the end of the main body portion 231 in a first direction Y. The tab 233 extends from the thinned portion 232 and is connected to the electrode terminal 22. The housing 21 includes a wall 213 surrounding the electrode assembly 23. The wall 213 includes a first portion 2113 and a second portion 2114 that are interconnected. The first portion 2113 is located radially outside the thinned portion 232 of the electrode assembly 23, and the thickness of the first portion 2113 is greater than the thickness of the second portion 2114.

[0077] The outer casing 21 serves as a component in the battery cell 2 to form a sealed cavity 2112, which can accommodate the electrode assembly 23 and the electrolyte. The electrode assembly 23, as a component housed in the outer casing 21, is in contact with the electrolyte, and active ions (e.g., lithium ions) can be conducted between the electrode assembly 23 and the electrolyte.

[0078] The main body 231, the thinning part 232, and the tab 233 can be different structures in the electrode assembly 23. The thinning part 232 is the structure of the electrode assembly 23 corresponding to the part of the electrode sheet with a thinning area, where the thinning area of ​​the electrode sheet is the area where the polar active material on the electrode sheet is thinned. The main body 231 is the structure of the electrode assembly 23 corresponding to the part of the electrode sheet without a thinning area. The thinning part 232 is connected to the end of the main body 231 in the first direction Y, and the tab 233 is led out from the thinning part 232 along the first direction Y and electrically connected to the electrode terminal 22.

[0079] Because of the stacked electrode arrangement in the electrode assembly 23, the gap between the electrode layers in the thinned portion 232 formed by the stacking of the electrode thinning area is easily changed by external forces, which is not easy to control and can easily affect the service life of the battery cell 2.

[0080] The electrode terminal 22 may be a component disposed on the housing 21, and may be used to electrically connect to an external electrical device or charging device of the battery cell 2 so that the battery cell 2 can be charged and discharged. The electrode terminal 22 may include, but is not limited to, a columnar structure, and those skilled in the art may configure it according to the actual situation.

[0081] The wall 213 can be a structure within the housing 21 used to surround the electrode assembly 23, and it can form a structure for protecting internal components such as the electrode terminals 22. The first part 2113 and the second part 2114 are different structural parts in the wall 213, and they are connected to each other to form the wall 213 surrounding the electrode assembly 23.

[0082] The first part 2113 is located on the radial outer side of the thinned part 232 of the electrode assembly 23. By configuring the thickness of the first part 2113 to be greater than the thickness of the second part 2114, the structural strength of the first part 2113 can be enhanced. During the expansion of the electrode assembly 23, the first part 2113 corresponding to the thinned part 232 can provide a greater binding force to limit the expansion of the electrode assembly 23, and can provide a better binding effect on the expansion of the thinned part 232.

[0083] For example, the thickness of the first part 2113 may be increased by protruding from the side opposite to the electrode assembly 23 relative to the second part 2114, so that the structural strength of the first part 2113 is greater than that of the second part 2114; the thickness of the first part 2113 may be increased by protruding from the side facing the electrode assembly 23 relative to the second part 2114, so that the structural strength of the first part 2113 is greater than that of the second part 2114; or the thickness of the first part 2113 may be increased by protruding from both sides relative to the second part 2114, so that the structural strength of the first part 2113 is greater than that of the second part 2114.

[0084] In the above structure, since the thickness of the first part 2113 in the wall 213 surrounding the electrode assembly 23 is greater than the thickness of the second part 2114 and the first part 2113 is located on the radial outer side of the thinned part 232 of the electrode assembly 23, the first part 2113 can provide a larger binding force to limit the expansion of the electrode assembly 23 during the expansion process. This can improve the increase or uneven distribution of the interlayer gap of the electrode in the electrode assembly 23, which is beneficial to extending the service life of the battery cell 2.

[0085] For example, the wall 213 can be a one-piece molded structure, that is, the first part 2113 and the second part 2114 can be made by one-piece molding process such as stamping and casting, so that the first part 2113 and the second part 2114 can be manufactured as a whole and simultaneously. This not only makes the processing and manufacturing of the wall 213 convenient, but also makes the overall structure of the wall 213 have good strength. The wall 213 can also be made by machining methods such as milling, by processing a whole blank, so that the outer shell 21 has low processing difficulty and processing cost.

[0086] In some embodiments, continuing to refer to FIG5, the wall 213 includes a main wall structure 2131 and a reinforcing structure 2132. The main wall structure 2131 surrounds the electrode assembly 23, and the reinforcing structure 2132 is connected to the surface of the main wall structure 2131 opposite to the electrode assembly 23 to form a first portion 2113.

[0087] The main wall structure 2131 can be the main structure in the wall 213, which surrounds the electrode assembly 23 and forms a sealed cavity 2112. The reinforcing structure 2132 can be a structure in the wall 213 used to increase the thickness to improve the structural strength. The reinforcing structure 2132 increases the thickness of a local area of ​​the wall 213 by connecting to the surface of the main wall structure 2131 opposite to the electrode assembly 23 to form a first part 2113, such that the first part 2113 formed by the main wall structure 2131 and the reinforcing structure 2132 protrudes relative to the second part 2114 on the side opposite to the electrode assembly 23.

[0088] By connecting the reinforcing structure 2132 to the surface of the main wall structure 2131 away from the electrode assembly 23, the first part 2113 is formed, which helps to reduce the difficulty of forming the first part 2113 and improve the ease of forming the first part 2113.

[0089] For example, the reinforcing structure 2132 can also be connected to the surface of the main wall structure 2131 away from the electrode assembly 23 by means of pressing, bonding or other methods, so that the first part 2113 is formed on the wall 213.

[0090] In some embodiments, the thickness of a local area of ​​the wall 213 can be increased by inserting a reinforcing member inside the wall 213 to form a first part 2113. Those skilled in the art can form the first part 2113 in the wall 213 according to the actual situation.

[0091] In some embodiments, along the radial direction of the electrode assembly 23, the projection of the first portion 2113 coincides with the projection of at least a portion of the thinned portion 232.

[0092] By making the projection of the first part 2113 along the radial direction of the electrode assembly 23 at least partially coincide with the projection of the thinned part 232 along the radial direction of the electrode assembly 23, at least a portion of the first part 2113 corresponds to the thinned part 232 in the radial direction of the electrode assembly 23. This allows the first part 2113 to better enhance the structural strength of the wall 213 in the corresponding area on the outer side of the thinned part 232. During the expansion of the electrode assembly 23, the first part 2113 can better restrain the expansion of the thinned part 232, thereby better preventing the increase or uneven distribution of the interlayer gap of the electrode sheets in the thinned part 232 of the electrode assembly 23, which is beneficial to extending the service life of the battery cell 2.

[0093] In some embodiments, the wall 213 includes a first wall 214 and a second wall 215 disposed opposite to each other, and a first portion 2113 is provided on both the first wall 214 and the second wall 215.

[0094] The first wall 214 and the second wall 215 can be two structural parts in the wall 213. The first wall 214 and the second wall 215 are arranged at intervals relative to each other, and the electrode terminal 22 is located between the first wall 214 and the second wall 215.

[0095] By providing a first part 2113 on both the first wall 214 and the second wall 215, the first wall 214 and the second wall 215, which are arranged opposite to each other, are provided with a first part 2113 that can enhance the structural strength. This allows the first wall 214 and the second wall 215 to relatively bind the electrode assembly 23 from both sides of the electrode assembly 23, providing better binding force for the expansion of the electrode assembly 23 and better improving the increase or uneven distribution of the interlayer gap of the electrode sheet in the electrode assembly 23.

[0096] In some embodiments, the wall 213 further includes a third wall 216 and a fourth wall 217 that are spaced apart from each other. The third wall 216 is connected between the first wall 214 and the second wall 215, and the fourth wall 217 is connected between the first wall 214 and the second wall 215. The electrode assembly 23 is located between the first wall 214 and the second wall 215 and between the third wall 216 and the fourth wall 217. The first wall 214, the second wall 215, the third wall 216 and the fourth wall 217 are all provided with a first part 2113, so that the first part 2113 is provided in the wall 213 surrounding the electrode assembly 23 of the outer shell 21 to increase the binding effect on the electrode assembly 23, which can better improve the increase or uneven distribution of the interlayer gap of the electrode in the electrode assembly 23.

[0097] In some embodiments, continuing to refer to FIG4, along the first direction Y, the dimension of the first portion 2113 is L1, and the dimension of the thinned portion 232 is L2.

[0098] By setting the dimension of the first part 2113 in the first direction Y to L1, setting the dimension of the thinned part 232 in the first direction Y to L2, and setting the ratio range of L1 and L2 to... The ratio of the size of the first part 2113 in the first direction Y to the size of the thinned part 232 in the first direction Y is within a suitable range, so that the first part 2113 not only has a sufficient size in the first direction Y to correspond to the thinned part 232 to provide sufficient binding force, but also reduces the size of the first part 2113 and reduces material waste.

[0099] In some embodiments,

[0100] By setting the range of the ratio of L1 and L2 to This design ensures that the first part 2113 has sufficient dimensions in the first direction Y to correspond to the thinned portion 232, providing sufficient binding force while minimizing material waste caused by excessive placement of the first part 2113. For example, the ratio of L1 to L2 can be set to 1, 1.5, or 1.8, ensuring that the first part 2113 has sufficient dimensions in the first direction Y to correspond to the thinned portion 232, providing sufficient binding force while minimizing material waste.

[0101] In some embodiments, along the first direction Y, the size of the first part 2113 is L1, and the size of the outer casing 21 is L3.

[0102] By setting the dimension of the first part 2113 in the first direction Y to L1, setting the dimension of the housing 21 in the first direction Y to L3, and setting the ratio range of L1 and L3 to... This ensures that the ratio of the size of the first part 2113 in the first direction Y to the size of the outer shell 21 in the first direction Y is within a suitable range. This not only ensures that the first part 2113 occupies a sufficient size of the outer shell 21 in the first direction Y, providing sufficient structural reinforcement for the outer shell 21, but also reduces material waste due to excessive arrangement of the first part 2113 assembly.

[0103] In some embodiments,

[0104] By setting the range of the ratio of L1 and L3 to This design ensures that the first part 2113 occupies a sufficient size in the outer shell 21 in the first direction Y to provide sufficient binding force, while also reducing material waste caused by excessive placement of the first part 2113. For example, the ratio of L1 to L3 can be set to 0.05, 0.15, or 0.25, so that the first part 2113 occupies a sufficient size in the outer shell 21 in the first direction Y to provide sufficient binding force, while minimizing material waste.

[0105] In some embodiments, along the radial direction of the electrode assembly 23, the thickness of the first portion 2113 is W1, and the thickness of the battery cell 2 is W2.

[0106] By setting the thickness of the first part 2113 in the radial direction of the electrode assembly 23 to W1, and the thickness of the battery cell 2 in the radial direction of the electrode assembly 23 to W2, and setting the ratio range of W1 and W2 to... This ensures that the ratio of the thickness of the first part 2113 in the radial direction to the thickness of the electrode assembly 23 is within a suitable range. This not only gives the first part 2113 sufficient structural strength to resist the expansion of the electrode assembly 23, but also helps to improve the resistance of the first part 2113 in the radial direction to the expansion force of the electrode assembly 23, and helps to improve the increase or uneven distribution of the interlayer gap of the electrode in the electrode assembly 23. Furthermore, it helps to reduce the waste of material caused by the excessive size of the first part 2113 in the radial direction of the electrode assembly 23.

[0107] In some embodiments,

[0108] By setting the range of the ratio of W1 and W2 to This allows the first part 2113 to have a suitable thickness relative to the electrode assembly 23 in the radial direction. This not only helps to improve the resistance of the first part 2113 to the expansion force of the electrode assembly 23 in the radial direction, but also helps to reduce the material waste caused by the excessive size of the first part 2113 in the radial direction of the electrode assembly 23.

[0109] In some embodiments, the surface of the first part 2113 facing the electrode assembly 23 is flush with the surface of the second part 2114 facing the electrode assembly 23.

[0110] By setting the surface of the first part 2113 facing the electrode assembly 23 to be flush with the surface of the second part 2114 facing the electrode assembly 23, the inner surface of the cavity 2112 enclosed by the outer shell 21 is flat, making it less likely for steps to appear on the inner surface of the cavity 2112 that accommodates the electrode assembly 23, which helps to reduce the possibility of the electrode assembly 23 being damaged by scratches.

[0111] In some embodiments, the housing 21 includes a housing 211 and an end cap 212. The housing 211 forms a cavity 2112 with an opening 2111. The opening 2111 is oriented along a first direction Y. An electrode assembly 23 is located in the cavity 2112. The end cap 212 covers the opening 2111. An electrode terminal 22 is disposed on the end cap 212. A first part 2113 and a second part 2114 are both located in the housing 211.

[0112] The housing 211 may be a component within the outer casing 21 that forms a cavity 2112 with an opening 2111. An end cap 212 is provided to seal the opening 2111. The electrode assembly 23 is located within the cavity 2112 formed by the housing 211, and the electrode terminal 22 is disposed on the end cap 212. The wall 213 may be a structural portion within the housing 211 that surrounds the electrode assembly 23, such that both the first part 2113 and the second part 2114 of the wall 213 are located within the housing 211.

[0113] The opening 2111 is oriented along the first direction Y, such that the thinned portion 232 in the electrode assembly 23 housed in the cavity 2112 can be located at the end near the opening 2111, which facilitates connection with the electrode terminal 22.

[0114] In some embodiments, the first part 2113 is connected to the opening 2111.

[0115] By connecting the first part 2113 to the opening 2111 of the housing 211, the first part 2113 can better cover the thinned part 232, which is beneficial to improve the binding effect of the first part 2113 on the expansion of the thinned part 232, improve the increase or uneven distribution of the interlayer gap of the electrode in the thinned part 232, and also improve the firmness of the connection of the end cap 212 to the opening 2111.

[0116] Some embodiments of this application also provide a battery 100, which includes the battery cell 2 provided by the above technical solution, and the battery 100 has a high energy density.

[0117] Some embodiments of this application also provide an electrical device that includes the battery 100 provided in the above-described technical solutions, the battery 100 being used to provide electrical energy. This electrical device can be any of the electrical devices described in the foregoing technical solutions.

[0118] Some embodiments of this application provide a battery cell 2, which includes a housing 21, electrode terminals 22, and electrode assembly 23. The housing 21 includes a shell 211 and an end cap 212. The shell 211 forms a cavity 2112 with an opening 2111. The end cap 212 covers the opening 2111. The electrode terminals 22 are disposed on the end cap 212. The electrode assembly 23 is accommodated in the cavity 2112. A thinned portion 232 in the electrode assembly 23 is connected to the end of the main body portion 231 in a first direction Y and is connected to the electrode terminal 22 through a tab 233. An integrally formed wall 213 in the shell 211 includes a first wall 214 and a second wall 215 disposed opposite to each other. The first wall 214 and the second wall 215 each include a first part 2113 and a second part 2114 that are connected to each other. The thickness of the first part 2113 is greater than the thickness of the second part 2114 and is connected to the opening 2111. The surface of the first part 2113 facing the electrode assembly 23 is flush with the surface of the second part 2114 facing the electrode assembly 23. In the above structure, since the thickness of the first part 2113 in the wall 213 surrounding the electrode assembly 23 is greater than the thickness of the second part 2114 and the first part 2113 is located on the radial outer side of the thinned part 232 of the electrode assembly 23, the first part 2113 can provide a larger binding force to limit the expansion of the electrode assembly 23 during the expansion process. This can improve the increase or uneven distribution of the interlayer gap of the electrode in the electrode assembly 23, which is beneficial to extending the service life of the battery cell 2.

[0119] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This 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 single battery cell, comprising: shell; Electrode terminals are disposed on the housing; An electrode assembly is housed within the housing. The electrode assembly includes a main body, a thinned portion, and an electrode tab. The thinned portion is connected to an end of the main body in a first direction, and the electrode tab extends from the thinned portion and is connected to the electrode terminal. The housing includes a wall surrounding the electrode assembly, the wall including a first portion and a second portion connected to each other; the first portion is located radially outside the thinned portion of the electrode assembly, and the thickness of the first portion is greater than the thickness of the second portion.

2. The battery cell according to claim 1, wherein, Along the radial direction of the electrode assembly, the projection of the first portion coincides with the projection of at least a portion of the thinned portion.

3. The battery cell according to claim 1 or 2, wherein, The wall is a one-piece molded structure.

4. The battery cell according to any one of claims 1 to 3, wherein, The wall includes a main wall structure and a reinforcing structure. The main wall structure surrounds the electrode assembly, and the reinforcing structure is connected to the surface of the main wall structure opposite to the electrode assembly to form the first part.

5. The battery cell according to any one of claims 1 to 4, wherein, The wall includes a first wall and a second wall disposed opposite to each other, and the first part is provided on both the first wall and the second wall.

6. The battery cell according to any one of claims 1 to 5, wherein, Along the first direction, the dimension of the first part is L1, and the dimension of the thinned part is L2.

7. The battery cell according to claim 6, wherein, 8. The battery cell according to any one of claims 1 to 7, wherein, Along the first direction, the dimension of the first part is L1, and the dimension of the outer shell is L3.

9. The battery cell according to claim 8, wherein, 10. The battery cell according to any one of claims 1 to 9, wherein, Along the radial direction of the electrode assembly, the thickness of the first portion is W1, and the thickness of the battery cell is W2.

11. The battery cell according to claim 10, wherein, 12. The battery cell according to any one of claims 1 to 11, wherein, The surface of the first part facing the electrode assembly is flush with the surface of the second part facing the electrode assembly.

13. The battery cell according to any one of claims 1 to 11, wherein, The housing includes a shell and an end cap. The shell forms a cavity with an opening, the opening being oriented along the first direction. The electrode assembly is located in the cavity. The end cap covers the opening. The electrode terminals are disposed on the end cap. Both the first part and the second part are located in the shell.

14. The battery cell according to claim 13, wherein, The first part is connected to the opening.

15. A battery comprising a battery cell as described in any one of claims 1 to 14.

16. An electrical device comprising the battery of claim 15, the battery being used to provide electrical energy.

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