Battery monomer, processing equipment, battery device and electric equipment

Abstract

The utility model discloses a battery monomer, processing equipment, a battery device and electric equipment, the battery monomer comprises an electrode assembly and a shell, the electrode assembly is arranged in the shell, the electrode assembly comprises two electrode pieces which are arranged in an overlapped manner, each electrode piece comprises a main body part and a thinned part, the thinned part is located at one side of the main body part in a first direction, and the thinned part is located at the other side of the main body part in the first direction; an embossed area is arranged on the thinned part of at least one pole piece, and embossed patterns in the embossed area extend along a second direction orthogonal to the first direction. Therefore, the knurling area is arranged on the thinned part of at least one pole piece, and the knurling in the knurling area extends along the second direction, so that the thickness of the thinned part is closer to that of the main body part, the influence of the thickness of the thinned part on cold pressing and hot pressing is reduced, and the bonding effect of the edge part of the pole piece is improved; and the problem of gap enlargement of the edge area of the electrode assembly can be improved, so that the edge lithium precipitation probability is reduced, and the stability and reliability of the battery monomer are improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery cell, processing equipment, battery device, and electrical equipment. Background Technology

[0002] In related technologies, a thinning section is formed between the tab and the main body of the electrode sheet. When the electrode sheet is wound into a core, the edge of the electrode sheet cannot be stressed during cold or hot pressing, which leads to poor adhesion and gaps at the edge of the electrode sheet. After the electrode sheet is further processed into a battery cell, the edge area of ​​the electrode assembly is thinner during battery cell cycling, and the outer shell of the battery cell cannot effectively provide restraint. During cycling, the gaps at the edge area of ​​the electrode assembly are prone to increase, which in turn leads to edge lithium plating. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. Therefore, one objective of this invention is to provide a battery cell, processing equipment, battery device, and electrical device in which the thickness of the thinned portion of the electrode sheet after winding is closer to the thickness of the main body, which can improve the bonding effect and also alleviate the problem of increased gaps in the edge areas of the electrode assembly, thereby reducing the probability of edge lithium plating.

[0004] In a first aspect, embodiments of this application provide a battery cell, including: an electrode assembly and a housing, wherein the electrode assembly is disposed within the housing, wherein the electrode assembly includes two overlapping electrode sheets, each electrode sheet including: a main body portion and a thinned portion, the thinned portion being located on one side of the main body portion in a first direction, and at least one electrode sheet having an embossed area on its thinned portion, and the embossing in the embossed area extending along a second direction orthogonal to the first direction.

[0005] According to the embodiments of this application, by providing an embossed area on the thinned portion of at least one electrode sheet, and the embossing in the embossed area extends along a second direction, the thickness of the thinned area can be increased, making the thickness of the thinned area closer to the thickness of the main body, thereby reducing the influence of the thickness of the thinned portion on cold pressing and hot pressing, improving the adhesion effect of the edge portion of the electrode sheet, and improving the problem of increased gap in the edge region of the electrode assembly, so as to reduce the probability of edge lithium plating and improve the stability and reliability of the battery cell.

[0006] According to some embodiments of this application, there are multiple embossed areas, which are arranged sequentially in a first direction. In a second direction, among adjacent embossed areas, the size of the embossed area relatively adjacent to the main body is smaller than the size of the embossed area relatively far from the main body.

[0007] In the above technical solution, the thickness difference between each region of the thinned part and the main body part in the first direction is smaller, and the consistency of the entire thinned part is better, which can further improve the bonding effect of the edge part of the electrode sheet during cold pressing and hot pressing.

[0008] According to some embodiments of this application, the embossing area includes a plurality of embossed patterns arranged sequentially along a third direction, wherein the first direction, the second direction, and the third direction are orthogonal to each other.

[0009] In the above technical solution, by having multiple embossings in the embossed area and arranging them in a row along a third direction, the thickness uniformity of the thinned part can be improved, and the thickness consistency of the thinned part can be better. This can further improve the support effect of the embossings in the thinned part, thereby improving the adhesion effect of the edge area of ​​the electrode sheet, and further reducing the variation of the edge gap of the electrode assembly, thereby reducing the probability of edge lithium plating.

[0010] According to some embodiments of this application, in a third direction, the gap between adjacent embossed patterns is 3mm to 5mm.

[0011] In the above technical solution, making the gap between adjacent embossings greater than or equal to 3mm can also make the maximum spacing between embossings more reasonable, thereby improving the thickness consistency of the thinned part. It can also make the minimum spacing between embossings more reasonable, thereby making the density of embossings more reasonable, reducing the processing difficulty, and taking into account the thickness consistency of the thinned part.

[0012] According to some embodiments of this application, in a third direction, among adjacent embossings, one extends toward the side facing the second direction, and the other extends toward the other side facing the second direction.

[0013] In the above technical solution, the embossing can be constructed as protrusions or depressions formed on the thinned part after being rolled on. In adjacent embossings, one embossing protrudes towards the first side and is observed as a protrusion from the first side, while the other embossing protrudes towards the second side and is observed as a depression from the second side. This makes the adjacent embossing structures alternate between protrusions and depressions. While increasing the thickness of the thinned part, it also makes the overall distribution of embossing on the thinned part more regular and the stress uniformity better. It can better withstand the pressure during cold pressing and hot pressing, thereby improving the edge bonding effect of the electrode sheet.

[0014] According to some embodiments of this application, the extension dimensions of the plurality of embossed patterns are equal in the second direction.

[0015] In the above technical solution, while improving the thickness uniformity of the thinned part, the thickness uniformity between the first and second sides of the thinned part can also be better, which can further improve the mechanical load-bearing capacity and dispersion effect of the thinned part, so as to improve the edge adhesion effect and reduce the deformation of the thinned part during subsequent charge and discharge cycles, thereby reducing the probability of edge lithium plating.

[0016] According to some embodiments of this application, in the second direction, the extension dimension L1 of the embossing is L2, and the dimension of the main body in the second direction is L2, and satisfies: 0.01L2≤L1≤0.1L2.

[0017] In the above technical solution, on the one hand, making the extension dimension of the embossing in the second direction greater than or equal to 0.01L2 can prevent the extension dimension of the embossing from being too small, so that the embossing can have a better effect on increasing the thickness of the thinned part; on the other hand, making the extension dimension of the embossing in the second direction less than or equal to 0.1L2 can prevent the extension dimension of the embossing from being too large, so as to reduce the thickness dimension of the thinned part from exceeding the thickness dimension of the main body.

[0018] According to some embodiments of this application, the embossing area includes a first embossing area, a second embossing area, and a third embossing area. The thickness L11 of the first embossing in the first embossing area is 0.05L2~0.1L2, the thickness L12 of the second embossing in the second embossing area is 0.03L2~0.05L2, and the thickness L13 of the third embossing in the third embossing area is 0.01L2~0.03L2.

[0019] In the above technical solution, the thickness of the first embossing, the second embossing, and the third embossing gradually decreases, that is, the thickness of the embossing adjacent to the main body is smaller, while the thickness of the embossing far from the main body is larger. This can make the difference between the thickness of the thinned part and the thickness of the main body smaller, and the thickness of the thinned part is closer to the thickness of the main body.

[0020] Secondly, this application proposes a processing device for battery cells, comprising: a first roller and a second roller, the first roller and the second roller being arranged opposite to each other in a second direction, the electrode sheet of the battery cell traveling along a third direction and located between the first roller and the second roller; wherein the first roller and the second roller are each provided with a knurling area, the knurling area being directly opposite the thinning section, and being adapted to roll-press the knurling area on the thinning section.

[0021] In the above technical solution, a feed channel is formed between the first roller and the second roller. The electrode sheet travels along the third roller and can pass through the feed channel. The first roller and the second roller can apply pressure toward the electrode sheet. During the process of the first roller and the second roller applying pressure toward the electrode sheet, the knurled areas on the first roller and the second roller can roll out embossing areas on the thinned part of the electrode sheet. By setting the embossing areas, the thickness of the thinned part is made closer to the thickness of the main body, thereby improving the edge bonding effect of the electrode sheet and improving the stability and reliability of the battery cell using the electrode sheet of this application.

[0022] According to some embodiments of this application, a first roller has a first knurled area, a second roller has a second knurled area, and the first knurling on the first knurled area and the second knurling on the second knurled area are alternately arranged.

[0023] This improves the thickness consistency of the thinned portion on both sides in the second direction.

[0024] Thirdly, this application provides a battery device, including: the battery cell in the above embodiments.

[0025] Fourthly, this application provides an electrical device, including the battery device described in the above embodiments.

[0026] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0027] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0028] Figure 1 This is a schematic diagram of an electrical device according to an embodiment of this application;

[0029] Figure 2 This is a schematic diagram of a battery device according to an embodiment of this application;

[0030] Figure 3 This is a schematic diagram of an electrode sheet according to an embodiment of this application (without the electrode tabs cut);

[0031] Figure 4 This is a schematic diagram of an electrode sheet (with the tabs cut out) according to an embodiment of this application.

[0032] Figure 5 This is a schematic diagram of an electrode sheet according to an embodiment of this application (showing the first embossing, the second embossing, and the third embossing).

[0033] Figure 6 This is a cross-sectional schematic diagram of an electrode sheet according to an embodiment of this application;

[0034] Figure 7 This is a schematic diagram illustrating the cooperation between the processing equipment and the electrode sheet according to an embodiment of this application;

[0035] Figure 8 This is a schematic diagram of a battery cell according to an embodiment of this application.

[0036] Figure label:

[0037] Electrode 100,

[0038] Main body 10,

[0039] Thinning section 20, embossing area 21, first embossing area 211, second embossing area 212, third embossing area 213.

[0040] Foil area 30, tab 31,

[0041] 200 processing equipment

[0042] First roller 210, first knurled area 2111, second roller 220, second knurled area 221.

[0043] Battery cell 300, casing 310, housing 311, end cap 312, electrode assembly 320.

[0044] Battery unit 400, electrical equipment 500, controller 600, motor 700.

[0045] First direction X, second direction Y, third direction Z. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0047] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0048] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0049] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0050] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0051] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0052] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0053] In the description of this utility model, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or it may include the first and second features not being in direct contact but being in contact through another feature between them.

[0054] In the description of this utility model, the terms "above", "over" and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0055] In this application, "multiple" means two or more (including two).

[0056] A single battery cell can be a rechargeable battery. A rechargeable battery is a battery cell that can be recharged after it has been discharged, allowing the active materials to be activated and the cell to continue to be used.

[0057] The battery cell 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.

[0058] The battery device 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, which may form a battery array, and the multiple battery cells may be connected in series, parallel, or in a mixed configuration via a busbar.

[0059] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells, such as forming a battery array.

[0060] As an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form an independent module. As another example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0061] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cell assemblies housed within the housing.

[0062] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0063] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0064] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first enclosure may be a top cover or a bottom plate.

[0065] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0066] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0067] The technical solutions described in the embodiments of this application are applicable to battery devices and electrical equipment using battery devices.

[0068] Electrical equipment can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the above-mentioned electrical equipment.

[0069] For ease of explanation, the following embodiments use a vehicle as an example of electrical equipment.

[0070] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle provided in some embodiments of this application. A battery device 400 is installed inside the vehicle, and the battery device 400 may be located at the bottom, front, or rear of the vehicle. The battery device 400 can be used to power the vehicle; for example, the battery device 400 can serve as the vehicle's operating power source.

[0071] The vehicle may also include a controller 600 and a motor 700. The controller 600 controls the battery device 400 to supply power to the motor 700, which serves as a load, for example, for the power needs of the vehicle during starting, navigation and driving.

[0072] In some embodiments of this application, the battery device 400 can not only serve as the operating power source for the vehicle, but also as the driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0073] Please refer to Figure 2 , Figure 2This is an exploded view of a battery device 400 provided in some embodiments of this application. The battery device 400 includes a housing for housing individual battery cells 300.

[0074] The housing is a component that houses the battery cells 300, providing space for multiple battery cells 300. The housing can employ various structures. In some embodiments, the housing may include a tray and a cover, which overlap to define a space for accommodating the battery cells 300. The tray and cover can be of various shapes, such as cuboids, cylinders, etc. The tray can be a hollow structure open on one side, and the cover can also be a hollow structure open on one side, with the open side of the cover overlapping the open side of the tray, thus forming a housing with a storage space. Alternatively, the tray can be a hollow structure open on one side, and the cover can be a plate-like structure, overlapping the open side of the tray, thus forming a housing with a storage space. As an example, the battery cell 300 can be a cylindrical battery cell, a prismatic battery cell, or a battery cell of other shapes (such as a pouch cell), and this application does not impose any particular limitations.

[0075] In the battery device 400, there can be one or more battery cells 300. If there are multiple battery cells 300, they can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 300 are connected in both series and parallel. Alternatively, multiple battery cells 300 can be first connected in series, parallel, or in a mixed configuration to form a battery module, and then multiple battery modules can be connected in series, parallel, or in a mixed configuration to form a whole, which is then housed in a casing. Another option is that all battery cells 300 can be directly connected in series, parallel, or in a mixed configuration, and then the whole assembly of all battery cells 300 is housed in a casing.

[0076] The battery cell 300 serves as the smallest energy unit of the battery device 400. The battery device 400 includes multiple battery cells 300, each of which includes a housing, an end cap, and an electrode assembly disposed within the housing.

[0077] like Figure 8 As shown, in some embodiments, the battery cell 300 may include: a housing, the housing including a housing 311 and an end cap 312, wherein an electrode assembly 320 is disposed within the housing 311, that is, the housing 311 is used to define an accommodating space having an installation opening, and the electrode assembly 320 is disposed therein.

[0078] For example, the housing 311 may include a base plate and a side plate. The side plate surrounds the periphery of the base plate and defines an accommodating space with a mounting opening. The electrode assembly 320 and other functional components may be disposed in the accommodating space. The end cap 312 covers the mounting opening of the housing 311 to isolate the internal environment of the battery cell 300 from the external environment. The shape of the end cap 312 is adapted to the shape of the housing 311. The end cap 312 may be supported by a material with a certain hardness and strength (such as aluminum alloy or carbon fiber plate). The end cap 312 can effectively protect the safety and reliability of the internal components of the housing 311 during compression and collision.

[0079] In some embodiments, the end cap 312 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this. In some embodiments, an insulating member can also be provided on the inner side of the end cap 312. The insulating member can be used to isolate the electrical connection components inside the housing 310 from the end cap 312 to reduce the risk of short circuit. For example, the insulating member can be plastic, rubber, etc., and an insulating sheet can also be provided between the electrode assembly 320 and the housing 310 to achieve insulation protection.

[0080] The outer casing 310 is a component used to cooperate with the end cap 312 to form the internal environment of the battery cell 300. This internal environment can accommodate the electrode assembly 320, electrolyte, and other components. The outer casing 310 and the end cap 312 can be independent components. A mounting opening can be provided on the outer casing 310, and the end cap 312 closes the opening at the mounting opening to form the internal environment of the battery cell 300. The outer casing 310 can have various shapes and sizes, such as cuboid, cylindrical, or hexagonal prism. Specifically, the shape of the outer casing 310 can be determined according to the specific shape and size of the electrode assembly 320. The material of the outer casing 310 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, or plastic; this embodiment does not impose any special limitations on this.

[0081] Electrode terminals may be further disposed on the end cap 312 or the housing 310. The electrode assembly 320 is a component in the battery cell 300 where the electrochemical reaction occurs. The housing 310 may contain one or more electrode assemblies 320.

[0082] There are multiple electrode assemblies 320 inside the housing 310. Each motor assembly 320 includes two overlapping electrode plates 100, which are overlapped and wound together to form the electrode assembly 320.

[0083] The two electrodes 100 can be defined as a first electrode and a second electrode, one formed as a positive electrode and the other as a negative electrode. The first electrode and the second electrode are wound together to form an electrode assembly 320, and a separator is usually provided between the first electrode and the second electrode. The portions of the first electrode and the second electrode containing active material constitute the main body portion 10, and the portions of the first electrode and the second electrode not containing active material are foil portions 30. The portion between the foil portion 30 and the main body portion 10 is formed as a thinned portion 20.

[0084] Combination Figure 3 and Figure 4 As shown, a first tab 31 corresponding to the first electrode and a second tab 31 corresponding to the second electrode can be obtained by cutting the foil portion 30. The first tab 31 and the second tab 31 can be formed as a positive tab 31 and a negative tab 31, respectively. The positive tab 31 and the negative tab 31 can be located together at one end of the main body portion 10 or at both ends of the main body portion 10, respectively. During the charging and discharging process of the battery device 400, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tab 31 connects to the electrode terminals to form a current circuit.

[0085] It should be noted that by providing a thinning portion 20 between the foil portion 30 and the main body portion 10, the thickness of the active material on the electrode 100 is reduced, thereby increasing the specific surface area of ​​the active material and improving the electrochemical performance of the electrode 100. This helps to improve the activity of the electrode 100, thereby increasing the energy density and cycle life of the battery cell 300. Furthermore, during charging and discharging, the thinning portion 20 can reduce edge effects and improve the stress in the corner area of ​​the electrode 100 after winding, reducing the risk of lithium plating and improving the safety and reliability of the battery.

[0086] However, since the thickness of the thinned portion 20 is less than that of the main body 10, the electrode 100 is wound to form a core and then the electrode assembly 320. During this process, the core needs to be cold-pressed and hot-pressed. During cold or hot pressing, the thinned portion 20 cannot bear the force, which leads to the technical problem of poor bonding effect after winding at the edge of the electrode 100. Furthermore, after the electrode assembly 320 is installed in the housing, the edge area of ​​the electrode 100 is thinner, which also leads to a gap between one end of each thinned portion 20 of the electrode assembly 320 and the housing 311. The housing 311 cannot provide effective restraint for the electrode assembly 320. During the cycle, the gap in the edge area of ​​the electrode assembly 320 is prone to increase, increasing the probability of edge lithium plating.

[0087] Based on this, this application proposes a battery cell 300 in which at least one electrode 100 of the electrode assembly 320 has an embossed area 21 on its thinned portion 20, so that the thickness difference between the thinned portion 20 and the main body portion 10 after winding is smaller, the adhesion effect of the edge of the electrode 100 after winding is better, and after being put into the casing, the casing 311 has a better binding effect on the end region of the electrode assembly 320, the probability of the gap in the edge region becoming larger is lower, and the probability of edge lithium plating is lower.

[0088] The following is for reference. Figures 1-8 The present invention describes a battery cell 300, a processing device 200, a battery device 400, and an electrical device 500 according to embodiments of the present invention.

[0089] like Figure 8 As shown, this application embodiment provides a battery cell 300, which includes an electrode assembly 320 and a housing 310, with the electrode assembly 320 disposed inside the housing 310.

[0090] Among them, combined Figure 4 and Figure 6 As shown, the electrode assembly 320 includes two overlapping electrode plates 100. Each electrode plate 100 includes a main body portion 10 and a thinned portion 20, with the thinned portion 20 located on one side of the main body portion 10 in a first direction.

[0091] It should be noted that in the embodiments of this application, the first direction corresponds to the width direction of the electrode 100, the second direction corresponds to the thickness direction of the electrode 100, and the third direction corresponds to the length direction of the electrode 100.

[0092] It is understood that, in the width direction of the electrode 100, at least one end of the main body 10 is provided with a foil portion 30, the foil portion 30 is cut to form an electrode tab 31, and a thinning portion 20 is formed between the foil portion 30 and the main body 10. The electrode 100 is wound along the length direction to form an electrode assembly 320. One or more electrode assemblies 320 are disposed in the housing 310 to form a battery cell 300. The electrode assembly 320 is inserted into the housing along the width direction of the electrode 100, and the thickness of the thinning portion 20 located at one end or both ends of the width of the main body 10 is less than the thickness of the main body 10. The thinning portion 20 with a smaller thickness will reduce the bonding effect during cold pressing or hot pressing during the winding process of the electrode 100. When the electrode assembly 320 is inserted into the housing, the edge area of ​​the electrode assembly 320 corresponding to the thinning portion 20 is prone to the phenomenon of increased edge gap during charge and discharge cycles, resulting in edge lithium plating.

[0093] Based on this, the present application provides an embossing region 21 on the thinned portion 20 of at least one of the two electrode sheets 100 of the electrode assembly 320, and the embossing in the embossing region 21 extends along a second direction orthogonal to the first direction.

[0094] In other words, by setting the embossing area 21, and the embossing in the embossing area 21 can extend along a second direction orthogonal to the first direction, the thickness of the thinning area 20 can be increased in the second direction orthogonal to the first direction, so that the size of the thinned portion 20 of the electrode sheet 100 with the embossing area 21 is close to the size of the main body portion 10.

[0095] For example, the thickness of the main body 10 is 5mm, the thickness of the thinning area 20 gradually decreases from 5mm to 3mm, and the setting of the embossing area 21, and the embossing extending along the second direction, can increase the thickness of the thinning area 20 so that the thinning area of ​​the thinning area 20 can be closer to the thickness of the main body 10.

[0096] Specifically, the electrode 100 is fed along a third direction and rolled along a second direction by an embossing device to form an embossing area 21 on the thinned portion 20. The embossing area 21 can make the surface of the thinned portion 20 have an uneven shape. By setting the embossing area 21 on the thinned portion 20, the thickness of at least a portion of the thinned portion 20 is increased, so that the thickness of the thinned portion 20 is closer to the thickness of the main body portion 10.

[0097] In this way, during the winding process of the electrode 100, the thickness difference between the thinned portion 20 and the main body 10 is smaller. During cold pressing or hot pressing, the area where the thinned portion 20 is located can withstand pressure, improving the edge stress and thus improving the edge adhesion effect of the electrode 100. At the same time, after the electrode assembly 320 is installed in the shell, during the charge and discharge cycle, since the thickness difference between the area where the thinned portion 20 of the electrode 100 is located and the area where the main body 10 is located is smaller, and the thinned portion 20 corresponds to at least one edge of the electrode assembly 320, the gap consistency between the edge area of ​​the electrode assembly 320 and the middle area corresponding to the main body 10 relative to the shell 311 is better. The shell 311 can also provide reliable support and restraint for the edge area, thereby suppressing the increase of the edge gap in the edge area, reducing the probability of edge lithium plating in the battery cell 300 during the cycle, and improving the working stability and reliability of the battery cell 300.

[0098] It should be noted that the fact that at least one electrode 100 has an embossed area 21 on its thinned area 20 means that one of the two electrodes 100 constituting the electrode assembly 320 has an embossed area 21, or the other has an embossed area 21, or both have an embossed area 21.

[0099] According to the embodiments of this application, the battery cell 300 has an embossed region 21 provided on the thinned portion 20 of at least one electrode 100, and the embossing in the embossed region 21 extends in the second direction. This increases the thickness of the thinned region 20, making the thickness of the thinned region 20 closer to the thickness of the main body 10. This reduces the influence of the thickness of the thinned portion 20 on cold pressing and hot pressing, improves the edge bonding effect of the electrode 100, and improves the problem of increased gap in the edge region of the electrode assembly 320. This reduces the probability of edge lithium plating and improves the stability and reliability of the battery cell 300.

[0100] like Figure 6 As shown, according to some embodiments of this application, there are multiple embossed areas 21, which are arranged sequentially in a first direction. In a second direction, among adjacent embossed areas 21, the size of the embossed area 21 that is relatively close to the main body 10 is smaller than the size of the embossed area 21 that is relatively far away from the main body 10.

[0101] Specifically, the thickness of the thinned portion 20 at one end adjacent to the main body portion 10 is greater than the thickness of the end adjacent to the foil portion 30. In the first direction, the thickness of the thinned portion 20 gradually decreases in the second direction as it moves away from the main body portion 10. This makes the size of the embossed area 21 relative to the main body portion 10 smaller than the size of the embossed area 21 relative to the main body portion 10. That is, the size of the embossed area 21 adjacent to the main body portion 10 is small, but the thickness difference between this area of ​​the thinned portion 20 and the main body portion 10 is small. The size of the embossed area 21 far from the main body portion 10 is large, but the thickness difference between this area of ​​the thinned portion 20 and the main body portion 10 is large. This makes the overall thickness difference between the thinned portion 20 and the main body portion 10 smaller after being compensated by the embossed area 21.

[0102] In this way, the thickness difference between each region of the thinned portion 20 and the main body 10 in the first direction is smaller, and the consistency of the entire thinned portion 20 is better, which can further improve the bonding effect of the edge portion of the electrode sheet 100 during cold pressing and hot pressing.

[0103] Combination Figure 5 and Figure 6 As shown, according to some embodiments of this application, the embossing area 21 includes a plurality of embossed patterns arranged sequentially along a first direction, and the first direction, the second direction, and the third direction are orthogonal to each other.

[0104] In other words, each embossing area 21 has multiple embossing patterns. The embossing patterns in each embossing area 21 can be arranged in one or more rows along the length of the electrode 100. Multiple embossing patterns can also be arranged in a row in the first direction, or in the third direction, two adjacent rows of embossing patterns can be staggered in the first direction.

[0105] In this way, by having multiple embossings in the embossed area 21 and arranging them in a row along a third direction, the thickness uniformity of the thinned portion 20 can be improved, making the thickness consistency of the thinned portion 20 better. This can further improve the support effect of the embossings in the thinned portion 20, thereby improving the adhesion effect of the edge area of ​​the electrode sheet 100 and further reducing the variation of the edge gap of the electrode assembly 320, thereby reducing the probability of edge lithium plating.

[0106] According to some embodiments of this application, in a third direction, the gap between adjacent embossed patterns is 3mm to 5mm.

[0107] Specifically, in each row of embossed patterns, the distance between adjacent embossed patterns is 3mm, 4mm, or 5mm, etc.

[0108] Therefore, by making the gap between adjacent embossings greater than or equal to 3mm, the maximum spacing between embossings can be made more reasonable, thereby improving the thickness consistency of the thinned part 20. The minimum spacing between embossings can also be made more reasonable, thereby making the density of embossings more reasonable. This can reduce the processing difficulty and take into account the thickness consistency of the thinned part 20.

[0109] According to some embodiments of this application, in a third direction, among adjacent embossings, one extends toward the side facing the second direction, and the other extends toward the other side facing the second direction.

[0110] Specifically, the electrode 100 is defined with two sides in the thickness direction as the first side and the second side, respectively. The embossing can be constructed as a protrusion or depression formed on the thinned part 20 after being rolled. Embossing areas 21 can be provided on both the first side and the second side. In the embossing area 21 provided on the first side, among adjacent embossings, one embossing protrudes towards the first side and is observed as a protrusion from the first side, and the other embossing protrudes towards the second side and is observed as a depression from the first side. This makes the embossing structure of adjacent parts in the third direction alternate between protrusions and depressions. While increasing the thickness of the thinned part 20, it can also make the overall distribution of embossing on the thinned part 20 more regular, the stress uniformity better, and it can better withstand the pressure during cold pressing and hot pressing, thereby improving the edge bonding effect of the electrode 100.

[0111] According to some embodiments of this application, the extension dimensions of the plurality of embossed patterns are equal in the second direction.

[0112] Specifically, within the same embossed area 21, among the multiple embossed patterns set on the first side, one adjacent embossed pattern protrudes towards the first side and the other protrudes towards the second side, and the protrusion size is the same. Similarly, among the multiple embossed patterns set on the second side, one adjacent embossed pattern protrudes towards the first side and the other protrudes towards the second side, and the protrusion size is the same.

[0113] In this way, while improving the thickness uniformity of the thinned portion 20, the thickness uniformity between the first and second sides of the thinned portion 20 can also be better, which can further improve the mechanical load-bearing capacity and dispersion effect of the thinned portion 20, thereby improving the edge adhesion effect and reducing the deformation of the thinned portion 20 during subsequent charge-discharge cycles, thus reducing the probability of edge lithium plating.

[0114] According to some embodiments of this application, in the second direction, the extension dimension L1 of the embossing is L2, and the dimension of the main body 10 in the second direction is L2, and satisfies: 0.01L2≤L1≤0.1L2.

[0115] In other words, the extension dimension of the embossing along the second direction can be 0.01L2, 0.02L2, 0.03L2, 0.04L2, 0.05L2, 0.06L2, 0.07L2, 0.08L2, 0.09L2, 0.1L2, etc.

[0116] In this way, on the one hand, making the extension dimension of the embossing in the second direction greater than or equal to 0.01L2 can prevent the extension dimension of the embossing from being too small, so that the embossing can have a better effect on increasing the thickness of the thinned part 20; on the other hand, making the extension dimension of the embossing in the second direction less than or equal to 0.1L2 can prevent the extension dimension of the embossing from being too large, so as to reduce the thickness dimension of the thinned part 20 from exceeding the thickness dimension of the main body 10.

[0117] Combination Figure 5 As shown, according to some embodiments of this application, the embossing area 21 includes a first embossing area 211, a second embossing area 212, and a third embossing area 213. The thickness L11 of the first embossing in the first embossing area 211 is 0.05L2~0.1L2, the thickness L12 of the second embossing in the second embossing area 212 is 0.03L2~0.05L2, and the thickness L13 of the third embossing in the third embossing area 213 is 0.01L2~0.03L2.

[0118] For example, the thickness of the first embossing in the first embossing area 211 is 0.05L2, 0.06L2, 0.07L2, 0.08L2, 0.09L2, 0.1L2, the thickness of the second embossing in the second embossing area 212 is 0.03L2, 0.04L2, 0.05L2, etc., and the thickness of the third embossing in the third embossing area 213 is 0.01L2, 0.02L2, 0.03L2, etc.

[0119] As a result, the thickness of the first embossing, the second embossing, and the third embossing gradually decreases, that is, the thickness of the embossing adjacent to the main body 10 is smaller, while the thickness of the embossing far from the main body 10 is larger. This makes the difference between the thickness of the thinned portion 20 and the thickness of the main body 10 smaller, and the thickness of the thinned portion 20 is closer to the thickness of the main body 10.

[0120] Of course, each embossing area 21 can have multiple rows of embossing, and the multiple rows of embossing can be set in a third direction of staggered arrangement or sequential arrangement. Each row of embossing is constructed such that one concave and one convex in adjacent embossing. Correspondingly, two adjacent rows of embossing can also be constructed such that the embossing of the previous row is concave and the embossing of the corresponding next row is convex, so as to further improve the thickness uniformity of the thinned part 20.

[0121] like Figure 7 As shown, this application proposes a processing equipment 200 for a battery cell 300, including: a first roller 210 and a second roller 220, the first roller 210 and the second roller 220 being arranged opposite to each other in a second direction, and the electrode 100 traveling in a third direction and located between the first roller 210 and the second roller 220; wherein the first roller 210 and the second roller 220 are both provided with knurling areas, the knurling areas being directly opposite the thinning portion 20, and being adapted to roll-press the knurling area 21 on the thinning portion 20.

[0122] Specifically, a feeding channel is formed between the first roller 210 and the second roller 220. The electrode 100 of the battery cell 300 travels along the third path and can pass through the feeding channel. The first roller 210 and the second roller 220 can apply pressure toward the electrode 100. During the process of the first roller 210 and the second roller 220 applying pressure toward the electrode 100, the knurled areas on the first roller 210 and the second roller 220 can roll out the embossing area 21 on the thinned portion of the electrode 100. By setting the embossing area 21, the thickness of the thinned portion 20 is made closer to the thickness of the main body portion 10, thereby improving the edge bonding effect of the electrode 100 and improving the stability and reliability of the battery cell 300 using the electrode 100 of this application.

[0123] like Figure 7 As shown, according to some embodiments of this application, the first roller 210 has a first knurled area 2111, and the second roller 220 has a second knurled area 221. The first knurling on the first knurled area 2111 and the second knurling on the second knurled area 221 are alternately arranged.

[0124] In other words, the first knurling area 2111 is used to knurl on the first side of the thinning section 20, and the second knurling area 221 is used to knurl on the second side of the thinning section 20. During the feeding of the electrode sheet 100 along the third direction, the first roller 210 rotates synchronously and knurls with alternating protrusions and depressions on the first side roller. The second roller 220 rotates synchronously and knurls with alternating protrusions and depressions on the second side roller. The first knurling includes the first protruding knurling and the first recessed knurling. Correspondingly, the second knurling includes the second protruding knurling and the second recessed knurling. When the first protruding knurling presses against the first side of the thinning section 20, the second recessed knurling presses against the first side of the thinning section 20. When the first recessed knurling presses against the first side of the thinning section 20, the second protruding knurling presses against the second side of the thinning section 20, so as to form alternating knurling on the first side and the second side.

[0125] This improves the thickness consistency of the thinned portion on both sides in the second direction.

[0126] It should be noted that, in the embodiments of this application, the electrode assembly 320 includes one or more electrode assemblies 300, and at least one electrode assembly 300 is configured as a core structure, the core being wound together by a first electrode sheet, a second electrode sheet, and a diaphragm. At least one of the first electrode sheet and the second electrode sheet is configured as the electrode sheet 100 in the embodiments of this application, that is, at least one of the positive electrode sheet and the negative electrode sheet is configured as the electrode sheet 100 of this application, preferably the positive electrode sheet is configured as the electrode sheet 100 of this application.

[0127] like Figure 2 As shown, this application provides a battery device 400, including: the battery cell 300 in the above embodiment.

[0128] like Figure 1 As shown, this application provides an electrical device 500, including: the battery device 400 in the above embodiment.

[0129] Other components and operations of the electrode 100, processing equipment 200, battery cell 300, battery device 400, and electrical equipment 500 according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0130] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0131] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery cell, characterized in that, include: Electrode assembly and housing, wherein the electrode assembly is disposed within the housing; wherein The electrode assembly includes two overlapping electrode sheets, each electrode sheet including a main body (10) and a thinned portion (20), the thinned portion (20) being located on one side of the main body (10) in a first direction; and at least one of the electrode sheets has an embossed area (21) on the thinned portion (20), and the embossing in the embossed area (21) extends along a second direction orthogonal to the first direction.

2. The battery cell according to claim 1, characterized in that, There are multiple embossed areas (21), and the multiple embossed areas (21) are arranged sequentially in the first direction. In the second direction, among the adjacent embossed areas (21), the size of the embossed area (21) that is relatively close to the main body (10) is smaller than the size of the embossed area (21) that is relatively far away from the main body (10).

3. The battery cell according to claim 1 or 2, characterized in that, The embossing area (21) includes a plurality of embossing patterns arranged sequentially along a third direction, wherein the first direction, the second direction, and the third direction are orthogonal to each other.

4. The battery cell according to claim 3, characterized in that, In the third direction, the gap between adjacent embossed patterns is 3mm to 5mm.

5. The battery cell according to claim 3, characterized in that, In the third direction, among the adjacent embossings, one extends toward one side of the second direction, and the other extends toward the other side of the second direction.

6. The battery cell according to claim 5, characterized in that, The multiple embossed patterns have equal extension dimensions in the second direction.

7. The battery cell according to claim 3, characterized in that, In the second direction, the extension dimension L1 of the embossing and the dimension L2 of the main body (10) in the second direction satisfy: 0.01L2≤L1≤0.1L2.

8. The battery cell according to claim 7, characterized in that, The embossing area (21) includes a first embossing area (211), a second embossing area (212), and a third embossing area (213). The thickness L11 of the first embossing in the first embossing area (211) is 0.05L2~0.1L2, the thickness L12 of the second embossing in the second embossing area (212) is 0.03L2~0.05L2, and the thickness L13 of the third embossing in the third embossing area (213) is 0.01L2~0.03L2.

9. A processing device for a single battery cell, characterized in that, include: A first roller (210) and a second roller (220) are arranged opposite to each other in the second direction. In any one of claims 1-8, the electrode of the battery cell travels in the third direction and is located between the first roller (210) and the second roller (220). in Both the first roller (210) and the second roller (220) are provided with knurling areas, which are directly opposite the thinning part (20) and are adapted to roll the knurling area (21) on the thinning part (20).

10. The battery cell processing equipment according to claim 9, characterized in that, The first roller (210) has a first knurled area (2111), and the second roller (220) has a second knurled area (221). The first knurling on the first knurled area (2111) and the second knurling on the second knurled area (221) are alternately arranged.

11. A battery device, characterized in that, include: The battery cell according to any one of claims 1-8.

12. An electrical appliance, characterized in that, include: The battery device according to claim 11.

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