Battery monomer, battery device and electric device

Abstract

The invention provides a battery monomer, a battery device and a power utilization device, the battery monomer comprises a shell, an electrode assembly, an end cover assembly and an adapter, the shell is enclosed to form a containing cavity with an opening, the electrode assembly is arranged in the containing cavity, the electrode assembly comprises a plurality of pole pieces with opposite polarities, each pole piece comprises a pole piece main body and a pole lug, and the pole lug is arranged in the containing cavity. The tabs of the pole pieces with the same polarity are stacked, the tabs and the pole piece main body are arranged in parallel, the end cover assembly covers the opening and comprises a cover body and an electrode terminal arranged on the cover body, the adapter is arranged between the electrode assembly and the end cover assembly, and the adapter comprises a first adapter part and a second adapter part which are arranged in an intersecting manner; the first switching part is electrically connected with the electrode terminal, and the second switching part extends towards the accommodating cavity and is electrically connected with the tab. According to the battery monomer in the embodiment of the invention, the risk of tab breakage in the charging and discharging process of the battery monomer can be reduced, the battery performance is improved, and the service life is prolonged.

Description

Technical Field

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

[0003] In existing battery cells, after the electrode assembly is fabricated, the tabs need to be folded to make electrical connections with the electrode terminals. However, after folding the tabs, stress will exist at the folding point. During the charging and discharging process, the battery will transfer the force to the folded position, which may cause the tabs to crack. This will prevent the capacity of the cracked area from being utilized, resulting in a loss of battery capacity. Summary of the Invention

[0004] In view of the above problems, this application provides a battery cell, a battery device, and an electrical device, which can reduce the risk of tab breakage during battery cell charging and discharging, and improve the performance and service life of the battery cell.

[0005] In a first aspect, this application provides a battery cell, which includes a housing, an electrode assembly, an end cap assembly, and an adapter. The housing encloses a receiving cavity with an opening. The electrode assembly is disposed within the receiving cavity and includes multiple electrodes with opposite polarities. Each electrode includes an electrode body and an electrode tab. The electrode tabs of electrodes with the same polarity are stacked together and are arranged parallel to the electrode body. The end cap assembly covers the opening and includes a cover body and electrode terminals disposed on the cover body. The adapter is disposed between the electrode assembly and the end cap assembly and includes a first adapter portion and a second adapter portion that intersect. The first adapter portion is electrically connected to the electrode terminals, and the second adapter portion extends toward the receiving cavity and is electrically connected to the electrode tabs.

[0006] In this embodiment, by including a first adapter portion and a second adapter portion that are intersected, the electrical connection between the electrode assembly and the electrode terminal can be achieved without folding the tabs, thereby reducing the risk of tab breakage during the charging and discharging of the battery cell and improving the performance and service life of the battery cell.

[0007] In some embodiments, a plurality of electrodes are stacked along a first direction, and tabs are disposed on one side of the electrode body along a second direction. The plurality of tabs are converged along the first direction, a first adapter is disposed on the tab side of the electrode assembly, and a second adapter extends along the second direction and overlaps with the tabs, wherein the second direction intersects the first direction.

[0008] In some embodiments, in the second direction, the side surface of the first adapter facing the electrode assembly abuts against the end face of the tab, which enables the internal structure of the battery cell to be more compact, saves and reduces the space occupied along the second direction after the adapter and electrode assembly are connected, and improves the energy density of the battery.

[0009] In some embodiments, the tabs do not protrude from the electrode body in the second direction, which makes the structure more compact. After the end cap assembly closes the opening, the distance between the end cap assembly and the electrode assembly in the second direction is reduced, making more reasonable use of the internal space of the housing and improving the energy density of the battery cell.

[0010] In some embodiments, the electrode terminals include a first electrode terminal and a second electrode terminal, and the electrode plates include a plurality of first electrode plates and a plurality of second electrode plates with opposite polarities. The tabs of the first electrode plates and the second electrode plates are both arranged parallel to the electrode plate body. In the paired adapters, one adapter connects the first electrode terminal and the tab of the first electrode plate, and the other adapter connects the second electrode terminal and the tab of the second electrode plate.

[0011] In some embodiments, the first electrode has a first notch, and the second electrode has a second notch. The projection of the first notch of the first electrode along a first direction at least partially overlaps with the tab of the second electrode, and the projection of the second notch of the second electrode along the first direction at least partially overlaps with the tab of the first electrode.

[0012] In some embodiments, the electrode assembly further includes a separator membrane disposed between the first electrode and the second electrode along a first direction. The separator membrane has a plurality of third notches, one of which overlaps with the first notch, and another third notch overlaps with the second notch.

[0013] In some embodiments, the tabs of the first electrode are located at the corners of the first electrode, and / or the tabs of the second electrode are located at the corners of the second electrode. This makes it easier to perform the tab washing and edge trimming processes during electrode fabrication, and also makes it easier to stack multiple tabs, thereby improving the reliability of the connection.

[0014] In some embodiments, the housing is open at one end along the second direction, and the tabs of the first electrode and the second electrode are located on the same side of the electrode assembly along the second direction; or, the housing is open at both ends along the second direction, and the tabs of the first electrode and the second electrode are located on opposite sides of the electrode assembly along the second direction.

[0015] In some embodiments, the tabs of the first electrode and the second electrode are disposed on both sides of the electrode assembly along a third direction, the third direction intersecting the first direction and the second direction.

[0016] In some embodiments, the cover includes a first cover portion and a second cover portion, with electrode terminals disposed on the second cover portion. The second cover portion is recessed relative to the first cover portion toward the receiving cavity, which can make the external structure of the formed battery cell more regular, increase the utilization rate of external space, facilitate the assembly of battery cells, and improve utilization.

[0017] In some embodiments, the surface of the electrode terminal away from the receiving cavity is flush with the surface of the first cover away from the receiving cavity, that is, the end cover assembly of the battery cell will not form a local protrusion at the position of the electrode terminal, and the external structure of the entire battery cell is cuboid, the structure is more regular, and the utilization rate of external space is increased.

[0018] In some embodiments, the first cover and the second cover have a height difference, and the electrode body is provided with a protrusion that protrudes toward the cover and is adapted to the surface of the first cover toward the receiving cavity, thereby improving the energy density of the battery cell.

[0019] Secondly, embodiments of this application provide a battery device including a plurality of battery cells according to the first aspect.

[0020] Thirdly, embodiments of this application provide an electrical device, including the battery device of the second aspect.

[0021] According to an embodiment of this application, the battery cell includes a casing, an electrode assembly, an end cap assembly, and an adapter. The electrode assembly includes multiple electrodes with opposite polarities, each electrode including an electrode body and a tab. Tabs of electrodes with the same polarity are stacked together. The adapter includes a first adapter portion and a second adapter portion that intersect each other. Without folding the tabs, the tabs are arranged parallel to the electrode body, and the second adapter portion extends towards the receiving cavity to electrically connect with the tabs. Simultaneously, the first adapter portion connects to the electrode terminals, thereby forming a conductive path between the electrode terminals and the electrode assembly. Since the battery cell in this embodiment does not require folding the tabs, it reduces the risk of tab breakage during charging and discharging, thus largely solving the problem of insufficient battery capacity due to tab breakage, and improving the performance and lifespan of the battery cell.

[0022] 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, the following are specific embodiments of this application. Attached Figure Description

[0023] 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. In the drawings:

[0024] Figure 1 These are schematic diagrams of the vehicle structure provided in some embodiments of this application;

[0025] Figure 2 These are exploded views of battery devices provided in some embodiments of this application;

[0026] Figure 3 These are exploded views of a single battery cell provided in some embodiments of this application;

[0027] Figure 4 This is a top view of a battery cell provided in some embodiments of this application;

[0028] Figure 5 yes Figure 4 Cross-sectional view along the AA direction;

[0029] Figure 6 yes Figure 5 Enlarged view of point B in the middle;

[0030] Figure 7 This is a manufacturing process diagram of a battery cell provided in some embodiments of this application;

[0031] Figure 8 These are exploded views of a battery cell provided in other embodiments of this application;

[0032] Figure 9 This is a top view of a battery cell provided in other embodiments of this application;

[0033] Figure 10 This is a side view of an end cap assembly provided in other embodiments of this application;

[0034] Figure 11 yes Figure 9 Cross-sectional view in the CC direction;

[0035] Figure 12 yes Figure 11 Enlarged view of point D in the middle.

[0036] The reference numerals in the detailed embodiments are as follows:

[0037] 100 battery packs, 200 controllers, 300 motors;

[0038] 10 individual battery cells, 20 casing cells;

[0039] 1. Housing; 2. Electrode assembly; 21. Electrode; 211. Electrode body; 212. Tab; 213. Protrusion; 21a. First electrode; 211a. First electrode body; 212a. First tab; 21b. Second electrode; 211b. Second electrode body; 212b. Second tab; 3. End cap assembly; 31. Cover; 311. First cover; 312. Second cover; 32. Electrode terminal; 32a. First electrode terminal; 32b. Second electrode terminal; 4. Adapter; 41. First adapter; 42. Second adapter; K1. First notch; K2. Second notch;

[0040] X is the third direction, Y is the first direction, and Z is the second direction. Detailed Implementation

[0041] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0042] It should be noted that, unless otherwise stated, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by those skilled in the art to which the embodiments of this application pertain.

[0043] In the description of the embodiments of this application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", 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 the embodiments of 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 the embodiments of this application.

[0044] Furthermore, technical terms such as "first" and "second" 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. In the description of the embodiments of this application, "a plurality of" means two or more, unless otherwise explicitly defined.

[0045] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0046] In the description of the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0047] With the development of the new energy industry, batteries are gradually moving towards higher energy density and higher power density. Currently, however, adapter plates are typically housed within the casing, and the tabs of the positive or negative electrode assembly are folded and folded together. One side of the adapter plate, along its thickness, connects to the tab, while the other side connects to the electrode terminals on the end cap assembly. However, folding the tabs creates stress on them. During charging and discharging, this stress is transferred to the tabs, potentially causing them to crack and preventing the battery from utilizing its capacity, resulting in capacity loss. Conversely, without folding the tabs, they cannot connect to the adapter plate.

[0048] Based on the above considerations, in order to solve the above problems, this application provides an embodiment of a new battery cell, which, by including an adapter with a first adapter portion and a second adapter portion arranged intersectingly, enables electrical connection between the tabs and electrode terminals without folding the tabs, thereby improving the energy density of the battery.

[0049] The technical solutions described in the embodiments of this application are applicable to battery devices and electrical devices that use battery devices.

[0050] Electrical devices can include 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 include airplanes, rockets, space shuttles, and spacecraft. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. 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. This application does not impose any special limitations on the above-mentioned electrical devices.

[0051] It should be understood that the technical solutions described in the embodiments of this application are applicable to all electrical devices including battery devices and those using batteries, but for the sake of brevity, the following embodiments are all illustrated using electric vehicles as examples.

[0052] Please see Figure 1 , Figure 1 The diagram shows the structural features of a vehicle provided in some embodiments of this application.

[0053] The vehicle has a battery device 100 installed inside, which can be located at the bottom, front, or rear of the vehicle. The battery device 100 can be used to power the vehicle; for example, it can serve as the vehicle's operating power source. The vehicle may also include a controller 200 and a motor 300. The controller 200 controls the battery device 100 to supply power to the motor 300, for example, to meet the vehicle's power needs during starting, navigation, and driving.

[0054] Please see Figure 2 , Figure 2 This is an exploded view of a battery device 100 provided in some embodiments of this application.

[0055] The battery device 100 mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells 10, which are connected in series, parallel, or mixed connections via a busbar. A battery cell assembly may be a battery module, which is formed by arranging and fixing multiple battery cells 10 into an independent module.

[0056] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells 10; as an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells 10 into a single module. As an example, a battery module can be formed by bundling multiple battery cells 10 together with cable ties.

[0057] In some embodiments, the battery device 100 may be a battery pack, which includes a housing 20 and one or more battery cell assemblies. The battery cell assemblies are housed within the housing 20 to encapsulate one or more battery cells 10, preventing liquids or other foreign matter from affecting the charging or discharging of the battery cells 10. As an example, the battery cell assembly may be a battery module, which can be housed within the housing 20 by fixing the battery module to the housing 20. Alternatively, the battery cell assembly may be housed within the housing 20 by directly fixing multiple battery cells 10 to the housing 20.

[0058] 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.

[0059] 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.

[0060] Please see Figure 3 , Figure 3 This is an exploded view of a battery cell 10 provided in some embodiments of this application.

[0061] This application provides a battery cell 10, which includes a housing 1, an electrode assembly 2, an end cap assembly 3, and an adapter 4.

[0062] The housing 1 is an assembly used to cooperate with the end cap assembly 3 to form the internal environment of the battery cell 10, wherein the formed internal environment can be used to accommodate the electrode assembly 2, electrolyte and other components.

[0063] The electrode assembly 2 includes multiple electrodes 21 with opposite polarities. Each electrode 21 includes an electrode body 211 and an electrode tab 212. Specifically, the multiple electrodes 21 with opposite polarities are positive electrodes and negative electrodes.

[0064] The battery cell 10 primarily functions by the movement of metal ions between the positive and negative electrode plates. The positive electrode plate comprises a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector and serves as the main body of the positive electrode plate, while the current collector without the positive active material layer acts as the positive electrode tab. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc.

[0065] The negative electrode sheet includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative current collector and serves as the main body of the negative electrode sheet. The current collector without the negative active material layer serves as the negative electrode tab. The material of the negative current collector can be copper, and the negative active material can be carbon or silicon, etc.

[0066] To ensure that a large current can pass through without melting, there are multiple positive electrode tabs stacked together, and multiple negative electrode tabs stacked together.

[0067] The end cap assembly 3 is a component that closes the opening of the housing 1 and isolates the internal environment of the battery cell 10 from the external environment. The end cap assembly 3 and the housing 1 can be independent components. The end cap assembly 3 includes a cover body 31 and electrode terminals 32 disposed on the cover body 31. The end cap assembly 3 includes two electrode terminals 32, which can be disposed on the cover body 31. The cover body 31 is typically flat, and the two electrode terminals 32 are fixed to the flat surface of the cover body 31. The two electrode terminals 32 are respectively a positive electrode terminal 32 and a negative electrode terminal 32.

[0068] Please refer to the following: Figures 3 to 6 , Figure 4 This is a top view of a battery cell 10 provided in some embodiments of this application. Figure 5 for Figure 4 Cross-sectional view along the AA direction. Figure 6 for Figure 5 Enlarged view of point B in the middle.

[0069] The battery cell 10 provided in this application embodiment has tabs 212 and electrode body 211 arranged in parallel. The adapter 4 is disposed between the electrode assembly 2 and the end cap assembly 3. The adapter 4 includes a first adapter portion 41 and a second adapter portion 42 arranged intersectingly. The first adapter portion 41 is electrically connected to the electrode terminal 32, and the second adapter portion 42 extends toward the receiving cavity and is electrically connected to the tabs 212.

[0070] By including an intersecting first adapter portion 41 and a second adapter portion 42 in the adapter 4, it is not necessary to fold the tab 212. That is, with the tab 212 parallel to the electrode body 211, the second adapter portion 42 extends towards the receiving cavity to electrically connect with the tab 212, while the first adapter portion 41 electrically connects with the electrode terminal 32, thereby forming a conductive path between the electrode terminal 32 and the electrode assembly 2. Since the battery cell 10 in this embodiment does not require folding the tab 212, it reduces the risk of the tab 212 breaking during charging and discharging, thus largely solving the problem of insufficient battery capacity due to tab 212 breakage, and improving the performance and service life of the battery cell 10.

[0071] In some alternative embodiments, multiple electrodes 21 are stacked along a first direction Y, and tabs 212 are disposed on one side of the electrode body 211 along a second direction Z. The multiple tabs 212 are converged along the first direction Y, a first adapter 41 is disposed on the tab side of the electrode assembly 2, and a second adapter 42 extends along the second direction Z and overlaps with the tabs 212, wherein the second direction Z intersects the first direction Y.

[0072] The overall external shape of the battery cell 10 can be set to a cuboid shape, the first direction Y can be the width direction of the battery cell 10, and the second direction Z is the height direction of the battery cell 10.

[0073] In a plurality of electrodes 21 of the same polarity, the tabs 212 are arranged to converge along the stacking direction of the electrodes 21, i.e., the first direction Y. By extending the second adapter portion 42 along the second direction Z and overlapping with the tabs 212, the connection area between the adapter and the second adapter portion 42 can be increased, thereby improving the reliability of the connection. At the same time, the connection structure is simple and easier to operate. Furthermore, it can also reduce the space occupied by the adapter 4 and the electrode assembly 2 along the second direction Z after connection, thereby increasing the energy density of the battery.

[0074] In some alternative embodiments, in the second direction Z, the side surface of the first adapter 41 facing the electrode assembly 2 abuts against the end face of the tab 212, thereby making the internal structure of the battery cell 10 more compact, further saving and reducing the space occupied by the adapter 4 and the electrode assembly 2 in the second direction Z after connection, and improving the energy density of the battery.

[0075] Optionally, among the multiple tabs 212, the tabs 212 located on both sides along the first direction Y converge toward the tab 212 located in the middle, so that the stacked tab structure is located in the middle position of the electrode assembly 2 along the first direction Y, thereby enabling the electrode assembly 2 to be uniformly stressed during the charging and discharging process of the battery cell 10, further reducing the risk of tab 212 breakage and improving the performance of the battery cell 10.

[0076] Optionally, the adapter 4 has a T-shaped structure. The first adapter portion 41 has a certain size along the first direction Y to connect with the electrode terminal 32. The second adapter portion 42 is disposed in the middle region of the first adapter portion 41 along the first direction Y and extends along the second direction Z to overlap with the tab 212. The structure of the adapter 4 is simpler and more reliable, and it can also reduce the risk of the adapter 4 detaching from the tab 212 under external force, thus improving reliability.

[0077] It is understandable that the second adapter 42 may overlap only one side surface of the electrode structure along the second direction Z, or the second adapter 42 may be arranged in pairs on both sides of the electrode structure along the second direction Z, with one second adapter 42 overlapping one side surface of the electrode structure along the second direction Z, and the other second adapter 42 overlapping both sides of the electrode structure along the second direction Z, so as to further improve the reliability of the electrical connection between the adapter 4 and the electrode 212.

[0078] Optionally, the number of electrode assemblies 2 can be one or more. When the number of electrode assemblies 2 is two or more, multiple electrode assemblies 2 can share the same adapter 4, that is, the adapter 4 is provided with multiple second adapter parts 42. The second adapter parts 42 can be arranged one-to-one with the electrode assemblies 2. The number of second adapter parts 42 can also be less than the number of electrode assemblies 2. At least one second adapter part 42 is disposed between two adjacent electrode assemblies 2 and electrically connected to the tabs 212 of the electrode assemblies 2 on both sides. The specific structure of the adapter 4 can be adjusted according to the specific structure of the electrode assembly 2, as long as it can meet the electrical connection requirements with the tabs 212.

[0079] Optionally, the first adapter 41 is welded to the electrode terminal 32, and the second adapter 42 is welded to the tab 212. This improves the connection strength between the adapter 4 and the end cap assembly 3 and the electrode assembly 2, reducing the probability of the end cap assembly 3 and the electrode assembly 2 detaching when the battery cell 10 is subjected to external force, thus improving the reliability of the electrode assembly 2. Specifically, the first adapter 41 is laser-welded to the electrode terminal 32 of the end cap assembly 3, and the second adapter 42 is ultrasonically welded to the tab 212.

[0080] Please see Figures 3 to 6 In some alternative embodiments, the tab 212 does not protrude from the electrode body 211 in the second direction Z, which makes the structure more compact. After the end cap assembly 3 is closed on the opening, the distance between the end cap assembly 3 and the electrode assembly 2 in the second direction Z is reduced, making more reasonable use of the internal space of the housing 1 and improving the energy density of the battery cell 10.

[0081] In some optional embodiments, the electrode terminal 32 includes a first electrode terminal 32a and a second electrode terminal 32b, and the electrode plate 21 includes a plurality of first electrode plates 21a and a plurality of second electrode plates 21b with opposite polarities. The tabs 212 of the first electrode plates 21a and the second electrode plates 21b are arranged parallel to the electrode plate body 211. In the paired adapters 4, one adapter 4 connects the first electrode terminal 32a and the tab 212 of the first electrode plate 21a, and the other adapter 4 connects the second electrode terminal 32b and the tab 212 of the second electrode plate 21b.

[0082] The first electrode 21a includes a first electrode body 211a and a first electrode tab 212a. Multiple first electrode tabs 21a are stacked, with the first electrode tabs 212a arranged parallel to the first electrode body 211a. The second electrode 21b includes a second electrode body 211b and a second electrode tab 212b. Multiple second electrode tabs 21b are stacked, with the second electrode tabs 212b arranged parallel to the second electrode body 211b. Each of the first electrode terminal 32a and the second electrode terminal 32b is provided with a corresponding adapter 4; one adapter 4 connects the first electrode terminal 32a and the first electrode tab 212a, and the other adapter 4 connects the second electrode terminal 32b and the second electrode tab 212b.

[0083] The first electrode 21a and the second electrode 21b have opposite polarities. For example, when the first electrode 21a is a positive electrode, the first electrode 21a is a negative electrode, the first electrode terminal 32a is a positive electrode terminal, and the second electrode terminal 32b is a negative electrode terminal. When the first electrode 21a is a negative electrode, the second electrode 21b is a positive electrode, the first electrode terminal 32a is a negative electrode terminal, and the second electrode terminal 32b is a positive electrode terminal.

[0084] By connecting the tabs 212 of the first electrode 21a and the second electrode 21b to the corresponding electrode terminals 32 via the adapter 4, the tab folding process can be eliminated during battery manufacturing. After the tabs 212 of the first electrode 21a and the second electrode 21b are welded to the corresponding adapter 4, they do not need to be folded and can be placed directly inside the housing 1. This largely solves the problem of the battery capacity not being fully utilized due to the breakage of the tabs 212, and improves the performance and service life of the battery cell 10.

[0085] Please see Figures 3 to 7 , Figure 7 This is a manufacturing process diagram of a battery cell 10 provided in some embodiments of this application. In some optional embodiments, a first electrode 21a is provided with a first notch K1, and a second electrode 21b is provided with a second notch K2. The projection of the first notch K1 of the first electrode 21a along the first direction Y at least partially overlaps with the tab 212 of the second electrode 21b, and the projection of the second notch K2 of the second electrode 21b along the first direction Y at least partially overlaps with the tab 212 of the first electrode 21a.

[0086] It is understandable that, in the manufacturing process of the aforementioned battery cell 10, a conventional method can be used to coat the current collector, followed by washing the tabs 212 and trimming the edges after cutting. Specifically, active material is coated onto the current collector of the first electrode 21a to form the first electrode body 211a. After cutting the first electrode body 211a, a portion of the active material is washed away to form tabs 212, and another portion of the first electrode body 211a is cut away to form the first notch K1. Similarly, active material is coated onto the current collector of the second electrode 21b to form the second electrode body 211b. After cutting the second electrode body 211b, a portion of the active material is washed away to form tabs 212, and another portion of the second electrode body 211b is cut away to form the second notch K2.

[0087] Optionally, washing away some active material to form tab 212 means removing the active material above the current collector of the electrode 21 by means of mechanical external force or chemical erosion. Mechanical external force can be in the form of an abrasive roller, and chemical erosion can be in the form of local solvent erosion. Solvents can be ethylene carbonate, methyl ethyl carbonate, etc. By adopting the above method, the active material of the electrode body 211 can be peeled off locally, thereby exposing the current collector, and the exposed part forms tab 212.

[0088] After the first electrode 21a and the second electrode 21b are stacked, the tab 212 of the second electrode 21b is exposed at the first notch K1 of the first electrode 21a. This makes it easier for the tabs 212 of multiple second electrode 21b to be folded together to electrically connect the second adapter 42 and the tabs 212 of the second electrode 21b. Similarly, the tab 212 of the first electrode 21a is exposed at the second notch K2 of the second electrode 21b. This makes it easier for the tabs 212 of multiple first electrode 21a to be folded together to electrically connect the second adapter 42 and the tabs 212 of the first electrode 21a.

[0089] Optionally, the first electrode 21a and the second electrode 21b can be configured as a square structure. Since the battery cell 10 in this embodiment is formed by washing away part of the active material after coating with active material to form the tab 212, the formed tab 212 does not protrude from the electrode body 211, which makes the structure more compact. After the end cap assembly 3 is closed on the opening, the distance between the end cap assembly 3 and the electrode assembly 2 along the second direction Z is reduced, making more reasonable use of the internal space of the housing 1 and improving the energy density of the battery cell 10.

[0090] In some alternative embodiments, the electrode assembly 2 further includes an isolation membrane disposed between the first electrode 21a and the second electrode 21b along a first direction Y. The isolation membrane has a plurality of third notches, one of which overlaps with the first notch K1, and another third notch overlaps with the second notch K2.

[0091] The separator has numerous interconnected micropores, allowing electrolyte ions to pass freely while maintaining good permeability to lithium ions. The separator can be made of materials such as PP or PE. When the separator is placed between the first electrode 21a and the second electrode 21b, multiple third notches can be formed on the separator, corresponding to the first notch K1 and the second notch K2, respectively. After the first electrode 21a and the second electrode 21b are stacked, the tabs 212 of the first electrode 21a and the second electrode 21b are exposed at the third notches, thereby reducing the impact on the closing of the tabs 212 and the connection between the adapter 4 and the tabs 212, and improving the reliability of the battery cell 10.

[0092] Please see Figures 3 to 7 In some optional embodiments, the tab 212 of the first electrode 21a is disposed at the corner of the first electrode 21a, and / or the tab 212 of the second electrode 21b is disposed at the corner of the second electrode 21b.

[0093] Taking a square structure as an example, the corner of the electrode 21 refers to the intersection of the two straight edges of the outer edge of the electrode 21. By setting the tabs 212 of the electrode 21 at the corners, it is easier to perform the washing and trimming processes of the tabs 212 during the preparation of the electrode 21. At the same time, it is also easier to stack multiple tabs 212, improving the reliability of the connection.

[0094] Optionally, the tab 212 can be configured as a triangle, fan-shaped, square, rhomboid, etc., and its specific shape can be adjusted according to the specific structure of the electrode assembly 2. This application does not make specific limitations in this regard.

[0095] Optionally, the position, shape, and size of the first notch K1, the second notch K2, and the third notch can be adjusted according to the corresponding tab 212. For example, the first notch K1, the second notch K2, and the third notch can also be set to square and overlap with the tab 212 to facilitate the stacking of multiple tabs 212 and the connection requirements between the adapter 4 and the tab 212.

[0096] In some alternative embodiments, the housing 1 is open at one end along the second direction Z, and the tabs 212 of the first electrode 21a and the second electrode 21b are located on the same side of the electrode assembly 2 along the second direction Z. Alternatively, the housing 1 is open at both ends along the second direction Z, and the tabs 212 of the first electrode 21a and the second electrode 21b are located on both sides of the electrode assembly 2 along the second direction Z.

[0097] When the housing 1 is open at one end along the second direction Z, one end cap assembly 3 can be provided. The first electrode terminal 32a and the second electrode terminal 32b are both provided on the same end cap assembly 3. The tabs 212 of the first electrode 21a and the second electrode 21b are located on the same side of the electrode assembly 2 along the second direction Z. When the housing 1 is open at both ends along the second direction Z, two end cap assemblies 3 can be provided. The first electrode terminal 32a and the second electrode terminal 32b are respectively provided on the two end cap assemblies 3. The tabs 212 of the first electrode 21a and the second electrode 21b are located on both sides of the electrode assembly 2 along the second direction Z, so as to facilitate the electrical connection between the electrode assembly 2 and the end cap assembly 3.

[0098] In some alternative embodiments, the tabs 212 of the first electrode 21a and the second electrode 21b are disposed on both sides of the electrode assembly 2 along a third direction X, which intersects with the first direction Y and the second direction Z. This makes it easier for the adapter 4 to connect to the tabs 212 of the first electrode 21a and the second electrode 21b respectively, while reducing the risk of contact between the adapters 4 and improving the reliability of the battery cell 10.

[0099] The third direction X is the length direction of the battery cell 10. When the tab 212 of the first electrode 21a and the tab 212 of the second electrode 21b are located on the same side of the electrode assembly 2 along the second direction Z, the tabs 212 of the first electrode 21a and the second electrode 21b can be respectively disposed at two corner positions of the electrode assembly 2 along the third direction X. When the tabs 212 of the first electrode 21a and the second electrode 21b are respectively located on both sides of the electrode assembly 2 along the second direction Z, the tab 212 of the first electrode 21a can be disposed at one end of the electrode assembly 2 along the third direction X, and the tab 212 of the second electrode 21b can be disposed at the other end of the electrode assembly 2 along the third direction X.

[0100] Please refer to the following: Figures 8 to 12 , Figure 8 and Figure 9 Exploded views and top views of the battery cell 10 provided in other embodiments of this application. Figure 10 This is a side view of the end cap assembly 3 provided in other embodiments of this application. Figure 11 for Figure 9 Sectional view in the CC direction, Figure 12 for Figure 11 Enlarged view of point D in the middle.

[0101] In some alternative embodiments, the cover 31 includes a first cover portion 311 and a second cover portion 312, with the electrode terminal 32 disposed on the second cover portion 312, and the second cover portion 312 being recessed relative to the first cover portion 311 toward the receiving cavity.

[0102] Since the electrode terminal 32 protrudes from the cover 31 along the second direction Z, the cover 31 is configured as an irregular structure, including a first cover portion 311 and a second cover portion 312 with a height difference. When the electrode terminal 32 is disposed on the second cover portion 312, by making the second cover portion 312 sink relative to the first cover portion 311, the external structure of the formed battery cell 10 can be made more regular, increasing the utilization rate of external space, facilitating the assembly of the battery cell 10, and improving utilization.

[0103] In some alternative embodiments, the surface of the electrode terminal 32 facing away from the receiving cavity is flush with the surface of the first cover 311 facing away from the receiving cavity. That is, the end cover assembly 3 of the battery cell 10 will not form a local protrusion at the position of the electrode terminal 32. The external structure of the entire battery cell 10 is cuboid, the structure is more regular, it is easier to assemble the battery cell 10, and it can also reduce the damage after the battery cell 10 is assembled and improve the performance of the battery cell 10.

[0104] Optionally, the dimension of the battery cell 10 along the second direction Z can be set to 100mm to 1m, that is, the height range of the battery cell 10 is not limited. Of course, the dimension of the battery cell 10 along the second direction Z can also be greater than 1m. This application does not make specific limitations on this.

[0105] In some alternative embodiments, the first cover portion 311 and the second cover portion 312 have a height difference, and the electrode body 211 is provided with a protrusion 213. The protrusion 213 protrudes towards the cover body 31 and is adapted to the surface of the first cover portion 311 facing the receiving cavity. That is, the cover body 31 can be configured as a Z-shaped cover body 31. The electrode body 211 is adapted to the end cap assembly 3. While the first cover portion 311 protrudes relative to the second cover portion 312, the electrode body 211 is also configured as an irregular structure, so as to improve the energy density of the battery cell 10 while making it easier to assemble the battery cell 10.

[0106] Optionally, during the fabrication of electrode assembly 2, the electrode bodies 211 of the first electrode 21a and the second electrode 21b can be directly cut to form a structure that is compatible with the end cap assembly 3, thereby simplifying the fabrication process.

[0107] Please refer to the following: Figures 8 to 12Taking a battery cell 10 from one embodiment of this application as an example, the specific structure of the battery cell 10 in this embodiment of the application will be described.

[0108] This application provides a battery cell 10, which includes a housing 1, an electrode assembly 2, an end cap assembly 3, and an adapter 4. The end cap assembly 3 includes a cover body 31 and a first electrode terminal 32a and a second electrode terminal 32b disposed on the cover body 31. The cover body 31 has a U-shaped structure and includes a first cover portion 311 and a second cover portion 312. The first electrode terminal 32a and the second electrode terminal 32b are disposed on the second cover portion 312. The second cover portion 312 is recessed relative to the first cover portion 311, and the surface of the electrode terminal 32a away from the receiving cavity is flush with the surface of the first cover portion 311 away from the receiving cavity.

[0109] The electrode assembly 2 includes a first electrode 21a, a separator, and a second electrode 21b stacked together. The electrode 21 includes an electrode body 211 and tabs 212. A first tab 212a is provided at one corner of the first electrode 21a and a first notch K1 is provided at the other corner. A second notch K2 is provided at one corner of the second electrode 21b and a second tab 212b is provided at the other corner. Multiple first tabs 212a are exposed to the second notch K2 and stacked on top of each other. The first tabs 212a are arranged parallel to the first electrode body 211a. Multiple second tabs 212b are exposed to the first notch K1 and stacked on top of each other. The second tabs 212b are arranged parallel to the second electrode body 211b. Both the first electrode tab 212a and the second electrode tab 212b are provided with corresponding adapters 4. The adapters 4 include a first adapter portion 41 and a second adapter portion 42 that are intersected. The first adapter portion 41 of one adapter 4 is electrically connected to the first electrode terminal 32a, and the second adapter portion 42 is electrically connected to the first electrode tab 212a. The first adapter portion 41 of the other adapter 4 is electrically connected to the second electrode terminal 32b, and the second adapter portion 42 is electrically connected to the second electrode tab 212b.

[0110] The battery cell 10 in this embodiment has a more regular external structure, making it easier to assemble. Furthermore, the battery cell 10 does not require folding the tabs 212; it can be electrically connected to the electrode terminals 32 via the adapter 4, with the tabs 212 and electrode body 211 arranged parallel to each other. This reduces the risk of tab 212 breakage during charging and discharging, largely solving the problem of insufficient battery capacity due to tab 212 breakage, and improving the performance and lifespan of the battery cell 10.

[0111] 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 battery cell, characterized in that, include: The shell encloses and forms a receiving cavity with an opening; An electrode assembly is disposed within the receiving cavity. The electrode assembly includes multiple electrodes with opposite polarities. Each electrode includes an electrode body and an electrode tab. Electrodes of the same polarity are stacked together, and the electrode tabs are arranged parallel to the electrode body. An end cap assembly is provided over the opening, the end cap assembly including a cap body and electrode terminals disposed on the cap body; An adapter is disposed between the electrode assembly and the end cap assembly. The adapter includes a first adapter portion and a second adapter portion that intersect each other. The first adapter portion is electrically connected to the electrode terminal, and the second adapter portion extends toward the receiving cavity and is electrically connected to the electrode tab.

2. The battery cell according to claim 1, characterized in that, The plurality of electrodes are stacked along a first direction, and the tab is disposed on one side of the electrode body along a second direction; The plurality of electrodes are converged along the first direction, the first adapter is disposed on the electrode tab side of the electrode assembly, the second adapter extends along the second direction and overlaps with the electrodes, and the second direction intersects with the first direction.

3. The battery cell according to claim 2, characterized in that, In the second direction, the side surface of the first adapter facing the electrode assembly abuts against the end face of the tab.

4. The battery cell according to claim 2, characterized in that, In the second direction, the tab does not protrude from the electrode body.

5. The battery cell according to any one of claims 2 to 4, characterized in that, The electrode terminals include a first electrode terminal and a second electrode terminal, and the electrode plate includes a plurality of first electrode plates and a plurality of second electrode plates with opposite polarities. The tabs of the first electrode plates and the second electrode plates are arranged parallel to the electrode plate body. In the pair of adapters, one adapter connects the first electrode terminal and the tab of the first electrode plate, and the other adapter connects the second electrode terminal and the tab of the second electrode plate.

6. The battery cell according to claim 5, characterized in that, The first electrode has a first notch, and the second electrode has a second notch; The projection of the first notch of the first electrode along the first direction at least partially overlaps with the tab of the second electrode, and the projection of the second notch of the second electrode along the first direction at least partially overlaps with the tab of the first electrode.

7. The battery cell according to claim 6, characterized in that, The electrode assembly further includes a separator membrane disposed between the first electrode and the second electrode along the first direction. The separator membrane has a plurality of third notches, one of which overlaps with the first notch and another of which overlaps with the second notch.

8. The battery cell according to claim 5, characterized in that, The tab of the first electrode is located at a corner of the first electrode, and / or the tab of the second electrode is located at a corner of the second electrode.

9. The battery cell according to claim 5, characterized in that, The housing is open at one end along the second direction, and the tabs of the first electrode and the second electrode are located on the same side of the electrode assembly along the second direction. Alternatively, the housing has openings at both ends along the second direction, and the tabs of the first electrode and the second electrode are respectively located on both sides of the electrode assembly along the second direction.

10. The battery cell according to claim 5, characterized in that, The tabs of the first electrode and the second electrode are disposed on both sides of the electrode assembly along a third direction, which intersects the first direction and the second direction.

11. The battery cell according to any one of claims 1 to 10, characterized in that, The cover includes a first cover portion and a second cover portion, the electrode terminal is disposed on the second cover portion, and the second cover portion is recessed relative to the first cover portion toward the receiving cavity.

12. The battery cell according to claim 11, characterized in that, The surface of the electrode terminal facing away from the receiving cavity is flush with the surface of the first cover facing away from the receiving cavity.

13. The battery cell according to claim 11, characterized in that, The first cover and the second cover have a height difference. The electrode body is provided with a protrusion that protrudes toward the cover and is adapted to the surface of the first cover toward the receiving cavity.

14. A battery device, characterized in that, It includes multiple battery cells according to any one of claims 1 to 13.

15. An electrical appliance, characterized in that, Includes the battery device as described in claim 14.

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