Battery cell, battery device, and electric device

Abstract

The application provides a battery monomer, a battery device and a power utilization equipment. The battery monomer comprises at least two electrode assemblies. The electrode assembly comprises a plurality of pole pieces. The plurality of pole pieces comprise a first pole piece, a second pole piece and a third pole piece which are sequentially stacked. The first pole piece comprises a first current collector and a first active material. The second pole piece comprises a second current collector, a second active material and a third active material. The third pole piece comprises a third current collector and a fourth active material. The polarity of the first active material is opposite to that of the second active material and the same as that of the third active material. The polarity of the third active material is opposite to that of the fourth active material. The at least two electrode assemblies are arranged in parallel. The battery monomer provided by the application can reduce the voltage of the battery monomer by arranging the at least two electrode assemblies in parallel, thereby reducing the risk of short circuit or voltage breakdown of the battery monomer and effectively improving the safety performance of the battery monomer.

Description

Technical Field

[0001] This application belongs to the field of battery technology, and more specifically, relates to a battery cell, battery device and electrical equipment. Background Technology

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry, and electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of this sustainable development. For electric vehicles, battery technology is a crucial factor in their development, and improving the safety performance of individual battery cells is a pressing issue that needs to be addressed. Utility Model Content

[0003] The purpose of this application is to provide a battery cell, a battery device, and an electrical appliance to solve the technical problem of poor safety performance of battery cells in related technologies.

[0004] To achieve the above objectives, the technical solution adopted in this application embodiment is as follows: a battery cell is provided, including a package and at least two electrode assemblies. The electrode assemblies are housed within the package. Each electrode assembly includes multiple electrode sheets, each including a first electrode sheet, a second electrode sheet, and a third electrode sheet stacked sequentially. The first electrode sheet includes a first current collector and a first active material disposed on the surface of the first current collector facing the second electrode sheet. The second electrode sheet includes a second current collector, a second active material disposed on the surface of the second current collector facing the first active material, and a third active material disposed on the surface of the second current collector facing the third electrode sheet. The third electrode sheet includes a third current collector and a fourth active material disposed on the surface of the third current collector facing the third active material. The polarity of the first active material is opposite to that of the second active material and the same as that of the third active material. The polarity of the third active material is opposite to that of the fourth active material. At least two electrode assemblies are connected in parallel.

[0005] The battery cell provided in this application embodiment has at least the following beneficial effects: In the battery cell provided in this application embodiment, the first electrode, the second electrode, and the third electrode in the electrode assembly are stacked sequentially. The first active material is disposed on the surface of the first current collector facing the second electrode, the second active material is disposed on the surface of the second current collector facing the first active material, the third active material is disposed on the surface of the second current collector facing the third electrode, and the fourth active material is disposed on the surface of the third current collector facing the third active material, so that the first electrode, the second electrode, and the third electrode are connected in series. Compared with the traditional method of all electrode plates being connected in series in a battery cell, the battery cell provided in this application embodiment, by arranging at least two electrode assemblies in parallel, can reduce the voltage of the battery cell while keeping the number of electrode plates in the battery cell unchanged, that is, keeping the capacity of the battery cell unchanged. This improves the situation of excessively high voltage in the battery cell, thereby reducing the risk of short circuit or voltage breakdown in the battery cell and effectively improving the safety performance of the battery cell.

[0006] In some embodiments of this application, the battery cell further includes a first insulating member disposed between two adjacent electrode assemblies.

[0007] By adopting the above technical solution, the parts of each electrode assembly, except for the parallel connection parts, can be insulated and separated, increasing the creepage distance between each electrode assembly, thereby further improving the safety performance of the battery cell.

[0008] In some embodiments of this application, a first insulating member is sandwiched between two adjacent electrode assemblies, and the thickness of the first insulating member is 4mm-10mm.

[0009] By adopting the above technical solution, the thickness of the first insulating component can be controlled within a suitable range, which not only increases the creepage distance between each electrode assembly, but also reduces the space occupied by the first insulating component, making the structure of the battery cell more compact, thereby effectively improving the volumetric energy density of the battery cell.

[0010] In some embodiments of this application, the battery cell further includes a second insulating member that covers the periphery of a plurality of electrodes in the electrode assembly.

[0011] By adopting the above technical solution, the individual electrode plates in the electrode assembly are effectively insulated and separated, further reducing the risk of short circuit in the battery cell and thus further improving the safety performance of the battery cell.

[0012] In some embodiments of this application, the electrode assembly includes a plurality of second electrodes, which are stacked sequentially between the first electrode and the third electrode.

[0013] By adopting the above technical solution, the capacity of the battery cell is effectively increased, and the number of second electrodes can be increased without adding other components, thereby effectively improving the energy density of the battery cell.

[0014] In some embodiments of this application, the second current collector includes a first current collector layer and a second current collector layer stacked on top of each other. The material of the first current collector layer is the same as that of the third current collector layer, and the material of the second current collector layer is the same as that of the first current collector layer. A second active material is disposed on the surface of the first current collector layer facing away from the second current collector layer, and a third active material is disposed on the surface of the second current collector layer facing away from the first current collector layer.

[0015] By adopting the above technical solution, it is easy to form the second electrode, and the structure is simple and easy to implement.

[0016] In some embodiments of this application, the battery cell further includes a first tab and a second tab, the first tab being electrically connected to a first current collector of at least two electrode assemblies and the second tab being electrically connected to a third current collector of at least two electrode assemblies, so as to arrange at least two electrode assemblies in parallel.

[0017] By adopting the above technical solution, it is only necessary to electrically connect the first tab to the first current collector of at least two electrode assemblies and the second tab to the third current collector of at least two electrode assemblies to realize the parallel arrangement of at least two electrode assemblies, thereby realizing the output or input current of the battery cell. Compared with the traditional method of leading out tabs from all the electrodes in the battery cell, the number of tabs is effectively reduced, the space utilization of the battery cell is effectively improved, and the energy density of the battery cell is effectively improved.

[0018] In some embodiments of this application, the electrode assembly further includes a third tab and a fourth tab, the third tab being connected to a first current collector, the fourth tab being connected to a third current collector, the first tab being connected to the third tabs of at least two electrode assemblies, and the second tab being connected to the fourth tabs of at least two electrode assemblies.

[0019] By adopting the above technical solution, it is convenient to electrically connect the first electrode tab to the first current collector of at least two electrode assemblies and to the third current collector of at least two electrode assemblies.

[0020] In some embodiments of this application, both the first tab and the second tab are insulated from the package.

[0021] By adopting the above technical solutions, the risk of short circuits in individual battery cells is further reduced, thereby further improving the safety performance of individual battery cells.

[0022] In some embodiments of this application, the battery cell further includes a third insulating member disposed between the first tab and the package to insulate and separate the first tab from the package; and / or, the battery cell further includes a fourth insulating member disposed between the second tab and the package to insulate and separate the second tab from the package.

[0023] By adopting the above technical solution, the first and second tabs are effectively insulated and separated from the package, further reducing the risk of short circuit in the battery cell and thus further improving the safety performance of the battery cell.

[0024] In some embodiments of this application, the battery cell further includes a solid electrolyte disposed between two adjacent electrodes in the electrode assembly.

[0025] By adopting the above technical solutions, the safety performance of individual battery cells has been further improved.

[0026] In some embodiments of this application, the encapsulation is an aluminum-plastic film encapsulation.

[0027] By adopting the above technical solutions, the structure of the battery cell can be made more compact and the mass of the battery cell can be reduced, thereby effectively improving the energy density of the battery cell.

[0028] Secondly, embodiments of this application provide a battery device including a battery cell as described in any of the above embodiments.

[0029] The battery device provided in this application has at least the following beneficial effects: the battery device provided in this application effectively improves the safety performance of the battery device by using the battery cell as described in any of the above embodiments.

[0030] In some embodiments of this application, the battery device includes at least two battery cell assemblies, each comprising a plurality of battery cells connected in series, and at least two battery cell assemblies are connected in parallel.

[0031] By adopting the above technical solution, compared with the traditional method of arranging all battery cells in series sequentially in a battery device, the voltage of the battery device can be reduced without changing the number of battery cells in the battery device. This improves the situation of excessively high voltage in the battery device, thereby reducing the risk of short circuit or voltage breakdown in the battery device and further improving the safety performance of the battery device.

[0032] Thirdly, embodiments of this application provide an electrical device including a battery device as described in any of the above embodiments.

[0033] The electrical equipment provided in this application has at least the following beneficial effects: the electrical equipment provided in this application effectively improves the safety performance of the electrical equipment by using the battery device as described in any of the above embodiments. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the vehicle structure provided in an embodiment of this application;

[0036] Figure 2 This is an exploded structural diagram of a battery device provided in an embodiment of this application;

[0037] Figure 3 for Figure 2 A schematic diagram of the structure of a single battery cell in the battery device shown.

[0038] Figure 4 for Figure 3 The diagram shows a cross-sectional view of a single battery cell along line AA.

[0039] Figure 5 for Figure 4 A magnified structural diagram of point B of the battery cell shown.

[0040] Figure 6 for Figure 4 A magnified structural diagram of point C of the battery cell shown.

[0041] The following are the labeling elements in the figure:

[0042] 1000, vehicles;

[0043] 100. Battery device;

[0044] 10. Battery cell; 11. Package; 12. Electrode assembly; 121. First electrode; 1211. First current collector; 1212. First active material; 122. Second electrode; 1221. Second current collector; 12211. First current collector layer; 12212. Second current collector layer; 1222. Second active material; 1223. Third active material; 123. Third electrode; 1231. Third current collector; 1232. Fourth active material; 124. Third tab; 125. Fourth tab; 13. First insulating component; 14. Second insulating component; 15. First tab; 16. Second tab; 17. Third insulating component; 18. Fourth insulating component; 19. Solid electrolyte;

[0045] 20. Battery cell modules;

[0046] 30. Box; 31. First box; 32. Second box;

[0047] 200. Controller;

[0048] 300. Motor. Detailed Implementation

[0049] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0050] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0051] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0052] Furthermore, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," "third," or "fourth" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0053] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0054] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0055] Unless otherwise specified, all steps of this application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order; for example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0056] With technological advancements, the battery industry has developed rapidly, and the market share and usage frequency of battery devices are increasing, placing higher demands on their performance.

[0057] In related technologies, battery devices typically include multiple battery cells. The electrode assembly within each battery cell includes multiple electrodes, including a negative electrode, a positive electrode, and at least one bipolar electrode. The negative active material of the negative electrode is positioned opposite to the positive active material of the bipolar electrode, and vice versa, so that the electrodes are connected in series. However, compared to a configuration where all electrodes in a battery cell are connected in parallel, the voltage of the battery cell increases significantly with the same number of electrodes. This makes the battery cell more susceptible to short circuits or even voltage breakdown, leading to a decrease in the battery cell's safety performance.

[0058] Based on the above considerations, in order to improve the safety performance of the battery cell, in the battery cell provided in this application embodiment, the first electrode, the second electrode, and the third electrode in the electrode assembly are stacked sequentially. The first active material is disposed on the surface of the first current collector facing the second electrode, the second active material is disposed on the surface of the second current collector facing the first active material, the third active material is disposed on the surface of the second current collector facing the third electrode, and the fourth active material is disposed on the surface of the third current collector facing the third active material, so that the first electrode, the second electrode, and the third electrode are connected in series. Compared with the traditional method of all electrode plates being connected in series in a battery cell, the battery cell provided in this application embodiment, by arranging at least two electrode assemblies in parallel, can reduce the voltage of the battery cell while keeping the number of electrode plates in the battery cell unchanged, that is, while keeping the capacity of the battery cell unchanged. This improves the situation of excessively high voltage in the battery cell, thereby reducing the risk of short circuit or voltage breakdown in the battery cell and effectively improving the safety performance of the battery cell.

[0059] The battery device disclosed in this application can be used in electrical devices that use a battery device as a power source. These electrical devices can be, but are not limited to, vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools. 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. Spacecraft can be airplanes, rockets, space shuttles, or spacecraft. Electric toys can be stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Power tools can be 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.

[0060] For ease of explanation, the following embodiments will use a vehicle as an example of an electrical device according to an embodiment of this application.

[0061] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in an embodiment of this application. A battery device 100 is disposed inside the vehicle 1000, and the battery device 100 may be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 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 device 100 to supply power to the motor 300, for example, to meet the power requirements of the vehicle 1000 during starting, navigation, and driving.

[0062] In some embodiments of this application, the battery device 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.

[0063] The battery device 100 mentioned in the embodiments of this application may include one or more battery cell assemblies 20 for providing voltage and capacity. Each battery cell assembly 20 may include multiple battery cells 10, which are connected in series, parallel, or mixed connections via busbars.

[0064] In some embodiments, the battery cell assembly 20 is typically formed by arranging a plurality of battery cells 10.

[0065] As an example, the battery cell assembly 20 can be a battery module, which is formed by arranging and fixing multiple battery cells 10 into an independent module. As an example, the battery module can be formed by bundling multiple battery cells 10 together with cable ties.

[0066] In some embodiments, the battery device 100 may be a battery pack, which includes a housing 30 and one or more battery cell assemblies 20, the battery cell assemblies 20 being housed in the housing 30.

[0067] As an example, the battery cell assembly 20 can be a battery module, which can be housed in the housing 30 by fixing the battery module in the housing 30.

[0068] As an example, the battery cell assembly 20 can also be housed in the housing 30 by directly fixing multiple battery cells 10 to the housing 30.

[0069] As an example, the housing 30 may include a first housing 31 and a second housing 32. The first housing 31 and the second housing 32 are fastened together to form a closed space inside the housing 30 to house the battery cell assembly 20. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first housing 31 may be a top cover or a bottom plate.

[0070] As an example, the housing 30 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that the interior of the housing 30 forms an enclosed space to house the battery cell assembly 20.

[0071] In some embodiments, the housing 30 may be part of the chassis structure of the vehicle 1000. For example, a portion of the housing 30 may be at least a portion of the floor of the vehicle 1000, or a portion of the housing 30 may be at least a portion of the crossbeams and longitudinal beams of the vehicle 1000.

[0072] In this embodiment of the application, the battery cell 10 can be a secondary battery, which refers to the battery cell 10 that can be used again after being discharged by recharging to activate the active material.

[0073] The battery cell 10 can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0074] The technical solutions provided in the embodiments of this application will be described below with reference to the accompanying drawings.

[0075] Firstly, please refer to the following: Figures 3 to 6 This application provides a battery cell 10, including a package 11 and at least two electrode assemblies 12. The at least two electrode assemblies 12 are housed within the package 11. Each electrode assembly 12 includes multiple electrode sheets, each including a first electrode sheet 121, a second electrode sheet 122, and a third electrode sheet 123 stacked sequentially. The first electrode sheet 121 includes a first current collector 1211 and a first active material 1212 disposed on the surface of the first current collector 1211 facing the second electrode sheet 122. The second electrode sheet 122 includes a second current collector 1221 and a first active material 1212 disposed on the surface of the second current collector 1221 facing the first electrode sheet 122. The first active material 1212 has a second active material 1222 on its surface and a third active material 1223 on the surface of the second current collector 1221 facing the third electrode 123. The third electrode 123 includes a third current collector 1231 and a fourth active material 1232 on the surface of the third current collector 1231 facing the second electrode 122. The polarity of the first active material 1212 is opposite to that of the second active material 1222 and the same as that of the third active material 1223. The polarity of the third active material 1223 is opposite to that of the fourth active material 1232. At least two electrode assemblies 12 are arranged in parallel.

[0076] The package 11 provides an internal environment for the battery cell 10, thereby isolating components disposed within the package 11 (such as electrode assembly 12) from the external environment of the battery cell 10. The package 11 may be made of a rigid material or a flexible material.

[0077] In some embodiments, to make the battery cell 10 more compact and reduce its mass, thereby increasing its energy density, the encapsulation 11 can be made of a material with low mass and good mechanical and chemical stability. As an example, the encapsulation 11 is an aluminum-plastic film encapsulation 11.

[0078] Of course, in other embodiments, the encapsulation component 11 can also be made of a rigid material, which can be, but is not limited to, aluminum, aluminum alloy, stainless steel, etc. As an example, the encapsulation component 11 can include a housing and an end cap. An opening can be provided on the housing, and the end cap can be placed over this opening to seal the internal environment of the battery cell 10. Specifically, the housing and the end cap can form a common connection surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing, the end cap is then placed over the opening of the housing. The shape of the housing can be, but is not limited to, a cuboid, a cylinder, a hexagonal prism, etc. The shape of the end cap can be adapted to the shape of the housing to fit the housing.

[0079] Electrode assembly 12 is a component in the battery cell 10 where electrochemical reactions occur. In the embodiments of this application, electrode assembly 12 is manufactured using a stacking process, that is, electrode assembly 12 is formed by stacking multiple electrode sheets. The number of electrode assemblies 12 can be determined according to actual application needs, specifically 2, 3, 4, 5, etc.

[0080] In this embodiment, one of the first electrode 121 and the third electrode 123 is a positive electrode, and the other is a negative electrode. The second electrode 122 is a bipolar electrode, meaning that one of the first electrode 121 and the third electrode 123 constitutes the positive output terminal of the electrode assembly 12, and the other constitutes the negative output terminal of the electrode assembly 12. The surface of the first electrode 121 facing away from the second electrode 122 may or may not have the first active material 1212. Similarly, the surface of the third electrode 123 facing away from the second electrode 122 may or may not have the fourth active material 1232.

[0081] As an example, the first current collector 1211 is a positive current collector, the first active material 1212 is a positive active material, the third current collector 1231 is a negative current collector, and the fourth active material 1232 is a negative active material. Correspondingly, the second current collector 1221 has a negative side disposed opposite to the first electrode 121 and a positive side disposed opposite to the third electrode 123. The second active material 1222 is a negative active material, disposed on the negative side of the second current collector 1221 and opposite to the first active material 1212. The third active material 1223 is a positive active material, disposed on the positive side of the second current collector 1221 and opposite to the fourth active material 1232, so that the first electrode 121, the second electrode 122, and the third electrode 123 are connected in series.

[0082] As an example, the first current collector 1211 is a negative current collector, the first active material 1212 is a negative active material, the third current collector 1231 is a positive current collector, and the fourth active material 1232 is a positive active material. Correspondingly, the second current collector 1221 has a positive electrode side disposed opposite to the first electrode 121 and a negative electrode side disposed opposite to the third electrode 123. The second active material 1222 is a positive active material, disposed on the positive electrode side of the second current collector 1221 and opposite to the first active material 1212. The third active material 1223 is a negative active material, disposed on the negative electrode side of the second current collector 1221 and opposite to the fourth active material 1232, so that the first electrode 121, the second electrode 122, and the third electrode 123 are connected in series.

[0083] The positive electrode current collector can be a metal current collector or a composite current collector. The material of the metal current collector can be, but is not limited to, carbon, aluminum, stainless steel, low-carbon steel, titanium, etc. Composite current collectors are formed by forming metal materials (aluminum, stainless steel, low-carbon steel, titanium, etc.) on a polymer material substrate (such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0084] The negative electrode current collector can be a metal current collector or a composite current collector. The material of the metal current collector can be, but is not limited to, copper, copper-nickel alloys, etc. The composite current collector can be formed by forming a metal material (copper, copper-nickel alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0085] The positive electrode active material can be, but is not limited to, ternary lithium nickel cobalt manganese, lithium iron phosphate, lithium manganese iron phosphate, lithium manganese phosphate, lithium manganese oxide, lithium cobalt oxide, lithium nickel manganese, lithium-rich manganese, lithium titanate, etc.

[0086] The negative electrode active material can be, but is not limited to, lithium, graphite, hard carbon, soft carbon, silicon-carbon (Si / C), silicon-oxygen (SiO / C), tin-based alloys, germanium-based alloys, etc.

[0087] At least two electrode assemblies 12 are connected in parallel, meaning that the positive output terminals of at least two electrode assemblies 12 are electrically connected, and the negative output terminals of at least two electrode assemblies 12 are electrically connected. This can be a parallel connection of all electrode assemblies 12 in a single battery cell 10, or a parallel connection of some electrode assemblies 12 in a single battery cell 10 and a series connection of other electrode assemblies 12 in a single battery cell 10.

[0088] In some embodiments, the battery cell 10 further includes an electrolyte, which may be, but is not limited to, a liquid electrolyte, a solid electrolyte 19, a gel electrolyte, etc.

[0089] As an example, to further improve the safety performance of the battery cell 10, the battery cell 10 also includes a solid electrolyte 19, which is disposed between two adjacent electrodes in the electrode assembly 12. The solid electrolyte 19 can be, but is not limited to, a sulfide solid electrolyte 19, an oxide solid electrolyte 19, a halide solid electrolyte 19, and a polymer solid electrolyte 19. Specifically, the sulfide solid electrolyte 19 can be, but is not limited to, a sulfide crystalline solid electrolyte 19, a sulfide glass solid electrolyte 19, or a glass-ceramic solid electrolyte 19. The halide solid electrolyte 19 can be, but is not limited to, zirconium-based chlorides (such as LiZrCl, LiZrNbCl, LiZrNbCeCl, Li1ZrTaLaCl), indium-based chlorides (such as LiInCl, LiInNbCl, LiInNbLaCl), and yttrium-based chlorides (such as LiYCl, LiYZrCaCl).

[0090] In the battery cell 10 provided in this embodiment, the first electrode 121, the second electrode 122, and the third electrode 123 in the electrode assembly 12 are stacked sequentially. The first active material 1212 is disposed on the surface of the first current collector 1211 facing the second electrode 122, the second active material 1222 is disposed on the surface of the second current collector 1221 facing the first active material 1212, the third active material 1223 is disposed on the surface of the second current collector 1221 facing the third electrode 123, and the fourth active material 1232 is disposed on the surface of the third current collector 1231 facing the third active material 1223. The first electrode 121, the second electrode 122, and the third electrode 123 are connected in series. Compared with the traditional method of connecting all electrodes in a battery cell 10 in series, the battery cell 10 provided in this application embodiment, by connecting at least two electrode assemblies 12 in parallel, can reduce the voltage of the battery cell 10 without changing the number of electrodes in the battery cell 10, that is, without changing the capacity of the battery cell 10. This improves the situation of excessively high voltage in the battery cell 10, thereby reducing the risk of short circuit or voltage breakdown in the battery cell 10 and effectively improving the safety performance of the battery cell 10.

[0091] Please refer to some embodiments of this application as well. Figure 5 and Figure 6 The battery cell 10 also includes a first insulating member 13, which is disposed between two adjacent electrode assemblies 12.

[0092] The first insulating member 13 is a component used to insulate and separate adjacent electrode assemblies 12. Understandably, multiple electrode sheets are stacked to form the main body of the electrode assembly 12, and the first insulating member 13 is disposed between the main bodies of two adjacent electrode assemblies 12.

[0093] Understandably, the first insulating element 13 is made of insulating material. As an example, the first insulating element 13 is made of high voltage resistant insulating material. The high voltage resistant insulating material can be a polymer composite material made by adding functional fillers such as ceramic powder and silica, with materials such as organosilicon, epoxy resin, and polyurethane as the matrix.

[0094] In some embodiments, the surface area of ​​the first insulating member 13 facing the electrode assembly 12 is greater than or equal to the surface area of ​​the electrode assembly 12 facing the first insulating member 13, so that the first insulating member 13 can completely separate two adjacent electrode assemblies 12.

[0095] In some embodiments, two adjacent electrode assemblies 12 are arranged separately along the stacking direction of the electrode sheets, and a first insulating member 13 is disposed between two adjacent electrode assemblies 12.

[0096] In some embodiments, the battery cell 10 further includes a solid electrolyte 19 disposed between two adjacent electrodes in the electrode assembly 12, and a first insulating member 13 disposed between two adjacent electrode assemblies 12.

[0097] By adopting the above technical solution, the parts of each electrode assembly 12 except for the parallel connection part can be insulated and separated. For example, the main body part of each electrode assembly 12 can be insulated and separated, which increases the creepage distance between each electrode assembly 12, thereby further improving the safety performance of the battery cell 10.

[0098] In some embodiments of this application, please refer to Figure 5 The first insulating member 13 is sandwiched between two adjacent electrode assemblies 12, and the thickness H of the first insulating member 13 is 4mm-10mm.

[0099] The first insulating member 13 is sandwiched between two adjacent electrode assemblies 12, meaning that the two adjacent electrode assemblies 12 cooperate to clamp the first insulating member 13, that is, one side of the first insulating member 13 along the thickness direction abuts against one electrode assembly 12, and the other side of the first insulating member 13 along the thickness direction abuts against another electrode assembly 12.

[0100] The thickness H of the first insulating member 13 refers to the dimension of the first insulating member 13 in the direction from one electrode assembly 12 to the other electrode assembly 12 when the first insulating member 13 is clamped between two adjacent electrode assemblies 12. The thickness H of the first insulating member 13 can be determined according to the actual application requirements, and can be 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc.

[0101] By adopting the above technical solution, the thickness of the first insulating component 13 can be controlled within a suitable range, which not only increases the creepage distance between each electrode assembly 12, but also reduces the space occupied by the first insulating component 13, making the structure of the battery cell 10 more compact, thereby effectively improving the volumetric energy density of the battery cell 10.

[0102] Please refer to some embodiments of this application as well. Figure 5 and Figure 6 The battery cell 10 also includes a second insulating member 14, which covers the periphery of a plurality of electrodes in the electrode assembly 12.

[0103] The second insulating member 14 is a component used to insulatingly separate the peripheries of two adjacent electrodes in the electrode assembly 12.

[0104] Understandably, the second insulating element 14 is made of insulating material. For example, the second insulating element 14 is made of high voltage resistant insulating material. The high voltage resistant insulating material can be a polymer composite material made by adding functional fillers such as ceramic powder and silica, with materials such as organosilicon, epoxy resin, and polyurethane as the matrix.

[0105] The periphery of an electrode refers to the portion of the electrode where the current collector is not covered by the active material and is located on the outer periphery of the active material. For example, the portion of the first current collector 1211 that is not covered by the first active material 1212 and is located on the outer periphery of the first active material 1212 constitutes the periphery of the first electrode 121; similarly, the portion of the second current collector 1221 that is not covered by the second active material 1222 and the third active material 1223 and is located on the outer periphery of the second active material 1222 and the third active material 1223 constitutes the periphery of the third electrode 123. Furthermore, the portion of the third current collector 1231 that is not covered by the fourth active material 1232 and is located on the outer periphery of the fourth active material 1232 constitutes the periphery of the third electrode 123.

[0106] In some embodiments, in order to more effectively insulate and separate the plurality of electrodes in the electrode assembly 12, the periphery of the first electrode 121, the periphery of the second electrode 122, and the periphery of the third electrode 123 are completely covered by the second insulating member 14.

[0107] In some embodiments, the battery cell 10 further includes a solid electrolyte 19 disposed between two adjacent electrodes in the electrode assembly 12, and a second insulating member 14 covering the periphery of a plurality of electrodes in the electrode assembly 12.

[0108] By adopting the above technical solution, the individual electrode sheets in the electrode assembly 12 are effectively insulated and separated, further reducing the risk of short circuit in the battery cell 10, thereby further improving the safety performance of the battery cell 10.

[0109] Please refer to some embodiments of this application as well. Figure 5 and Figure 6 The electrode assembly 12 includes a plurality of second electrode plates 122, which are stacked sequentially between the first electrode plate 121 and the third electrode plate 123.

[0110] The number of second electrodes 122 can be determined according to the actual application requirements, specifically 2, 3, 4, 5, 6, etc.

[0111] Understandably, along the stacking direction of the electrodes, the second active material 1222 of the first second electrode 122 is arranged opposite to the first active material 1212, the third active material 1223 of the first second electrode 122 is arranged opposite to the second active material 1222 of the second second electrode 122, and so on, the third active material 1223 of the last second electrode 122 is arranged opposite to the fourth active material 1232 of the third electrode 123, so that the first electrode 121, the second electrode 122 and the third electrode 123 are arranged in series.

[0112] By adopting the above technical solution, the capacity of the battery cell 10 is effectively increased, and the number of the second electrode 122 can be increased without adding other components, thereby effectively improving the energy density of the battery cell 10.

[0113] Please refer to some embodiments of this application as well. Figure 5 and Figure 6 The second current collector 1221 includes a first current collector layer 12211 and a second current collector layer 12212 stacked on top of each other. The material of the first current collector layer 12211 is the same as that of the third current collector 1231, and the material of the second current collector layer 12212 is the same as that of the first current collector 1211. The second active material 1222 is disposed on the surface of the first current collector layer 12211 facing away from the second current collector layer 12212, and the third active material 1223 is disposed on the surface of the second current collector layer 12212 facing away from the first current collector layer 12211.

[0114] Understandably, the first flow collector 12211 and the second flow collector 12212 are closely fitted together to form a whole.

[0115] In some embodiments, the first current collector 1211 is a positive current collector, the first active material 1212 is a positive active material, the third current collector 1231 is a negative current collector, and the fourth active material 1232 is a negative active material. Correspondingly, the first current collector layer 12211 constitutes the negative side of the second current collector 1221, the second current collector layer 12212 constitutes the positive side of the second current collector 1221, the second active material 1222 is a negative active material, the second active material 1222 is disposed in the first current collector layer 12211 and is disposed opposite to the first active material 1212, and the third active material 1223 is a positive active material, the third active material 1223 is disposed in the second current collector layer 12212 and is disposed opposite to the fourth active material 1232, so that the first electrode 121, the second electrode 122, and the third electrode 123 are connected in series. As an example, the first current collector layer 12211 and the third current collector 1231 are both made of copper, while the second current collector layer 12212 and the first current collector 1211 are both made of aluminum.

[0116] In some embodiments, the first current collector 1211 is a negative current collector, the first active material 1212 is a negative active material, the third current collector 1231 is a positive current collector, and the fourth active material 1232 is a positive active material. Correspondingly, the first current collector layer 12211 constitutes the positive side of the second current collector 1221, the second current collector layer 12212 constitutes the negative side of the second current collector 1221, the second active material 1222 is a positive active material, the second active material 1222 is disposed in the first current collector layer 12211 and is disposed opposite to the first active material 1212, and the third active material 1223 is a negative active material, the third active material 1223 is disposed in the second current collector layer 12212 and is disposed opposite to the fourth active material 1232, so that the first electrode 121, the second electrode 122, and the third electrode 123 are connected in series. As an example, the first current collector layer 12211 and the third current collector 1231 are both made of aluminum, while the second current collector layer 12212 and the first current collector 1211 are both made of copper.

[0117] By adopting the above technical solution, it is easy to form the second electrode 122, which has a simple structure and is easy to implement.

[0118] Please refer to some embodiments of this application as well. Figure 5 and Figure 6 The battery cell 10 also includes a first tab 15 and a second tab 16. The first tab 15 is electrically connected to a first current collector 1211 of at least two electrode assemblies 12 and the second tab 16 is electrically connected to a third current collector 1231 of at least two electrode assemblies 12, so that at least two electrode assemblies 12 are arranged in parallel.

[0119] The first tab 15 and the second tab 16 are used to connect at least two electrode assemblies 12 in parallel to output or input current to the electrode assembly 12. Understandably, one of the first electrode 121 and the third electrode 123 constitutes the positive output terminal of the electrode assembly 12, and the other of the first electrode 121 and the third electrode 123 constitutes the negative output terminal of the electrode assembly 12. The first tab 15 is electrically connected to the first current collector 1211 of at least two electrode assemblies 12, and the second tab 16 is electrically connected to the third current collector 1231 of at least two electrode assemblies 12, so that at least two electrode assemblies 12 are connected in parallel.

[0120] In some embodiments, the package 11 is an aluminum-plastic film package 11, and the first tab 15 and the second tab 16 both extend into the external environment of the package 11 to output or input the current of the battery cell 10.

[0121] As an example, the first tab 15 and the second tab 16 may be disposed at the same end of the electrode assembly 12 and extend from the same end of the electrode assembly 12 into the external environment of the package 11.

[0122] As an example, the first tab 15 and the second tab 16 can be disposed at different ends of the electrode assembly 12 and extend from different ends of the electrode assembly 12 into the external environment of the package 11.

[0123] By adopting the above technical solution, it is only necessary to electrically connect the first tab 15 to the first current collector 1211 of at least two electrode assemblies 12 and the second tab 16 to the third current collector 1231 of at least two electrode assemblies 12 to realize the parallel arrangement of at least two electrode assemblies 12, thereby realizing the output or input current of the battery cell 10. Compared with the traditional method of leading out tabs from all the electrodes in the battery cell 10, the number of tabs is effectively reduced, the space utilization of the battery cell 10 is effectively improved, and the energy density of the battery cell 10 is effectively improved.

[0124] Please refer to some embodiments of this application as well. Figure 5 and Figure 6 The electrode assembly 12 also includes a third tab 124 and a fourth tab 125. The third tab 124 is connected to the first current collector 1211, the fourth tab 125 is connected to the third current collector 1231, the first tab 15 is connected to the third tab 124 of at least two electrode assemblies 12, and the second tab 16 is connected to the fourth tab 125 of at least two electrode assemblies 12.

[0125] In this embodiment, one of the first electrode 121 and the third electrode 123 constitutes the positive output terminal of the electrode assembly 12, and the other of the first electrode 121 and the third electrode 123 constitutes the negative output terminal of the electrode assembly 12. The second electrode 122 is not provided with tabs, and tabs are only provided on the first electrode 121 and the third electrode 123 to input or output the current of the electrode assembly 12.

[0126] In some embodiments, the third tab 124 is welded to the first current collector 1211, and the fourth tab 125 is welded to the third current collector 1231.

[0127] By adopting the above technical solution, it is convenient to electrically connect the first electrode tab 15 to the first current collector 1211 of at least two electrode assemblies 12 and to the second electrode tab 16 to the third current collector 1231 of at least two electrode assemblies 12.

[0128] Please refer to some embodiments of this application as well. Figure 5 and Figure 6 Both the first tab 15 and the second tab 16 are insulated from the package 11.

[0129] By adopting the above technical solution, the risk of short circuit in the battery cell 10 is further reduced, thereby further improving the safety performance of the battery cell 10.

[0130] In some embodiments of this application, please refer to Figure 5 The battery cell 10 also includes a third insulating member 17, which is disposed between the first tab 15 and the package 11 to insulate and separate the first tab 15 from the package 11.

[0131] The third insulating element 17 is a component used to insulate and separate the first tab 15 from the package 11.

[0132] Understandably, the third insulating element 17 is made of insulating material. For example, the third insulating element 17 is made of high voltage resistant insulating material. The high voltage resistant insulating material can be a polymer composite material made by adding functional fillers such as ceramic powder and silica to materials such as organosilicon, epoxy resin, and polyurethane as the matrix.

[0133] In some embodiments, a third insulating member 17 is disposed around the first tab 15 and between the first tab 15 and the package 11 to insulate and separate the first tab 15 from the package 11.

[0134] In other embodiments of this application, please refer to Figure 6 The battery cell 10 also includes a fourth insulating member 18, which is disposed between the second tab 16 and the package 11 to insulate and separate the second tab 16 from the package 11.

[0135] The fourth insulating element 18 is a component used to insulate and separate the second tab 16 from the package 11.

[0136] Understandably, the fourth insulating element 18 is made of insulating material. For example, the fourth insulating element 18 is made of high-voltage resistant insulating material. The high-voltage resistant insulating material can be a polymer composite material made by adding functional fillers such as ceramic powder and silica to materials such as organosilicon, epoxy resin, and polyurethane as the matrix.

[0137] In some embodiments, a fourth insulating member 18 is disposed around the second tab 16 and between the second tab 16 and the package 11 to insulate and separate the second tab 16 from the package 11.

[0138] Please refer to further embodiments of this application. Figure 5 and Figure 6 The battery cell 10 also includes a third insulating member 17 and a fourth insulating member 18. The third insulating member 17 is disposed between the first tab 15 and the package 11 to insulate and separate the first tab 15 from the package 11. The fourth insulating member 18 is disposed between the second tab 16 and the package 11 to insulate and separate the second tab 16 from the package 11.

[0139] By adopting the above technical solution, the first tab 15 and the second tab 16 are effectively insulated and separated from the package 11, which further reduces the risk of short circuit in the battery cell 10 and thus further improves the safety performance of the battery cell 10.

[0140] Secondly, please refer to Figure 2 This application provides a battery device 100, which includes a battery cell 10 as described in any of the above embodiments.

[0141] The battery device 100 provided in this application embodiment effectively improves the safety performance of the battery device 100 by using the battery cell 10 as described in any of the above embodiments.

[0142] In some embodiments of this application, please refer to Figure 2 The battery device 100 includes at least two battery cell assemblies 20, each battery cell assembly 20 including a plurality of battery cells 10 connected in series, and at least two battery cell assemblies 20 connected in parallel.

[0143] The number of battery cell modules 20 can be determined according to actual application needs, specifically 2, 3, 4, 5, etc.

[0144] At least two battery cell modules 20 are connected in parallel, meaning that the positive output terminals of at least two battery cell modules 20 are electrically connected, and the negative output terminals of at least two battery cell modules 20 are electrically connected. This can mean that all battery cell modules 20 in the battery device 100 are connected in parallel, or that a portion of the battery cell modules 20 in the battery device 100 are connected in parallel and another portion of the battery cell modules 20 in the battery device 100 are connected in series.

[0145] By adopting the above technical solution, compared with the traditional method of sequentially connecting all battery cells 10 in the battery device 100, the voltage of the battery device 100 can be reduced without changing the number of battery cells 10 in the battery device 100. This improves the situation of excessively high voltage in the battery device 100, thereby reducing the risk of short circuit or voltage breakdown in the battery device 100 and further improving the safety performance of the battery device 100.

[0146] Thirdly, please refer to Figure 1 This application provides an electrical device including a battery device 100 as described in any of the above embodiments.

[0147] The electrical equipment provided in this application embodiment effectively improves the safety performance of the electrical equipment by using the battery device 100 as described in any of the above embodiments.

[0148] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized in that, The battery cell includes: Package components; At least two electrode assemblies are housed within the package. Each electrode assembly includes multiple electrodes, each electrode comprising a first electrode, a second electrode, and a third electrode stacked sequentially. The first electrode includes a first current collector and a first active material disposed on the surface of the first current collector facing the second electrode. The second electrode includes a second current collector, a second active material disposed on the surface of the second current collector facing the first active material, and a third active material disposed on the surface of the second current collector facing the third electrode. The third electrode includes a third current collector and a fourth active material disposed on the surface of the third current collector facing the third active material. The polarity of the first active material is opposite to that of the second active material and the same as that of the third active material. The polarity of the third active material is opposite to that of the fourth active material. At least two electrode assemblies are connected in parallel.

2. The battery cell according to claim 1, characterized in that, The battery cell also includes a first insulating element, which is disposed between two adjacent electrode assemblies.

3. The battery cell according to claim 2, characterized in that, The first insulating element is sandwiched between two adjacent electrode assemblies, and the thickness of the first insulating element is 4mm-10mm.

4. The battery cell according to any one of claims 1-3, characterized in that, The battery cell also includes a second insulating element that covers the periphery of the plurality of electrodes in the electrode assembly.

5. The battery cell according to any one of claims 1-3, characterized in that, The electrode assembly includes a plurality of second electrodes, which are stacked sequentially between the first electrode and the third electrode.

6. The battery cell according to any one of claims 1-3, characterized in that, The second current collector includes a first current collector layer and a second current collector layer stacked on top of each other. The material of the first current collector layer is the same as that of the third current collector layer, and the material of the second current collector layer is the same as that of the first current collector layer. The second active material is disposed on the surface of the first current collector layer facing away from the second current collector layer, and the third active material is disposed on the surface of the second current collector layer facing away from the first current collector layer.

7. The battery cell according to any one of claims 1-3, characterized in that, The battery cell further includes a first tab and a second tab, wherein the first tab is electrically connected to the first current collector of at least two of the electrode assemblies and the second tab is electrically connected to the third current collector of at least two of the electrode assemblies, so that at least two electrode assemblies are arranged in parallel.

8. The battery cell according to claim 7, characterized in that, The electrode assembly further includes a third tab and a fourth tab. The third tab is connected to the first current collector, the fourth tab is connected to the third current collector, the first tab is connected to the third tab of at least two of the electrode assemblies, and the second tab is connected to the fourth tab of at least two of the electrode assemblies.

9. The battery cell according to claim 7, characterized in that, Both the first tab and the second tab are insulated from the package.

10. The battery cell according to claim 9, characterized in that, The battery cell further includes a third insulating member disposed between the first electrode tab and the encapsulation member to insulate and separate the first electrode tab from the encapsulation member; and / or, The battery cell further includes a fourth insulating element, which is disposed between the second tab and the package to insulate and separate the second tab from the package.

11. The battery cell according to any one of claims 1-3, characterized in that, The battery cell also includes a solid electrolyte, which is disposed between two adjacent electrodes in the electrode assembly.

12. The battery cell according to any one of claims 1-3, characterized in that, The encapsulation component is an aluminum-plastic film encapsulation component.

13. A battery device, characterized in that, The battery device includes a battery cell as described in any one of claims 1-12.

14. The battery device according to claim 13, characterized in that, The battery device includes at least two battery cell assemblies, each battery cell assembly comprising a plurality of battery cells connected in series, and at least two battery cell assemblies connected in parallel.

15. An electrical appliance, characterized in that, The electrical equipment includes the battery device as described in claim 13 or 14.

Images