Battery monomer, battery device, energy storage device and power utilization device

Abstract

The embodiment of the utility model provides a battery monomer, a battery device, an energy storage device and an electric device, and belongs to the technical field of batteries. The battery monomer comprises a shell and an electrode assembly, the electrode assembly is accommodated in the shell and comprises a pole piece and a diaphragm, a positive pole piece in the pole piece comprises a positive current collector body and a positive pole connected with the positive current collector body, and a coating layer, an insulating layer and a bonding layer are arranged on the surface of the positive current collector body. The coating layer comprises a main body region and a thinned region, the thickness of the thinned region is smaller than that of the main body region, the thinned region is arranged on two sides of the positive electrode current collector body along the width direction, and the insulating layer is arranged on one side, far away from the main body region, of the thinned region; and at least one insulating layer is bonded with the diaphragm through the bonding layer. According to the utility model, the risk of generating a gap between the positive pole piece and the negative pole piece can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and more specifically, to a battery cell, a battery device, an energy storage device and an electric device. Background Art

[0002] During the battery unit manufacturing process, the ends of the electrode assembly will be interfered by external forces, which can easily cause gaps between the positive and negative electrode plates, thereby causing lithium deposition, triggering internal short circuits, and reducing energy density, which needs to be improved. Utility Model Content

[0003] The utility model provides a battery cell, a battery device, an energy storage device and an electric device, so as to reduce the risk of a gap between a positive electrode sheet and a negative electrode sheet.

[0004] In the first aspect, an embodiment of the utility model provides a battery cell, comprising: a shell and an electrode assembly, the electrode assembly being accommodated in the shell, comprising a pole piece and a diaphragm, the positive pole piece in the pole piece comprising a positive current collector body and a positive pole ear connected to the positive current collector body, the surface of the positive current collector body being provided with a coating layer, an insulating layer and an adhesive layer, the coating layer comprising a main body area and a thinning area having a thickness less than that of the main body area, the thinning area being arranged on both sides of the positive current collector body along the width direction, and the insulating layer being arranged on a side of the thinning area away from the main body area; at least one of the insulating layers being bonded to the diaphragm through the adhesive layer.

[0005] In the above technical solution, by providing an adhesive layer on at least one insulating layer, at least one of the insulating layers is bonded to the diaphragm through the adhesive layer, which can increase the bonding force between the insulating layer of the positive electrode sheet and the diaphragm, thereby effectively reducing the risk of generating a gap between the positive electrode sheet and the negative electrode sheet, improving the safety performance of the battery cell, and at the same time reducing the internal gap of the battery cell, thereby improving the space utilization and energy density of the battery cell.

[0006] In some embodiments, the side of the adhesive layer facing away from the insulating layer is flush with the side of the main region facing away from the positive electrode current collector body.

[0007] In some embodiments, the orthographic projection of the insulating layer on the positive electrode current collector body is located within the orthographic projection of the adhesive layer on the positive electrode current collector body.

[0008] In some embodiments, the orthographic projection of the adhesive layer on the positive electrode current collector body and the orthographic projection of the coating layer on the positive electrode current collector body have an overlapping area.

[0009] In some embodiments, the positive projection of the adhesive layer on the projection plane in the thickness direction of the positive current collector body does not coincide with the positive projection of the positive electrode tab on the projection plane in the thickness direction of the positive current collector body.

[0010] In some embodiments, the insulating layers on both sides of the coating layer are bonded to the separator through the adhesive layer.

[0011] In some embodiments, it satisfies: 0μm ≤ h1 ≤ 10μm, where h1 is the height of the adhesive layer on one side above the main body area in the thickness direction of the positive current collector body; and / or,

[0012] It satisfies: 1mm ≤ n1 ≤ 2mm, where n1 is the difference between the length of the insulating layer in the length direction of the positive current collector body and the length of the adhesive layer in the length direction of the positive current collector body.

[0013] In some embodiments, the adhesive layer is a hot melt adhesive layer or a hot melt adhesive tape.

[0014] In a second aspect, an embodiment of the present invention provides a battery device, including: a plurality of battery cells described in any one of the above embodiments.

[0015] In a third aspect, an embodiment of the present invention provides an energy storage device, including: a plurality of battery cells described in any one of the above embodiments or a plurality of battery devices described in any one of the above embodiments, and the battery cells or the battery devices are used to store or provide electrical energy.

[0016] In a fourth aspect, an embodiment of the present invention provides an electrical device, including: a battery cell described in any one of the above embodiments, a battery device described in any one of the above embodiments, or an energy storage device described in any one of the above embodiments, and the battery cell or the battery device is used to store or provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 It is a schematic structural diagram of an energy storage system provided by some embodiments of the present invention;

[0019] Figure 2 It is a schematic structural diagram of a charging network provided by some embodiments of the present invention;

[0020] Figure 3 Structural schematic diagram of a vehicle provided by some embodiments of the present utility model;

[0021] Figure 4 Exploded view of the structure of a battery device provided by some embodiments of the present utility model;

[0022] Figure 5 One of the structural schematic diagrams of an electrode assembly provided by some embodiments of the present utility model;

[0023] Figure 6 Another structural schematic diagram of an electrode assembly provided by some embodiments of the present utility model;

[0024] Figure 7 One of the structural schematic diagrams of a positive electrode plate provided by some embodiments of the present utility model;

[0025] Figure 8 Another structural schematic diagram of a positive electrode plate provided by some embodiments of the present utility model.

[0026] Reference numerals:

[0027] Energy storage device 1, power conversion device 2, power generation device 3, charging pile 4, connector 5;

[0028] Vehicle 1000;

[0029] Battery device 100;

[0030] Box body 10, first box body 11, second box body 12;

[0031] Battery cell 20, electrode assembly 22, positive electrode plate 221, positive current collector body 2211, coating layer 22111, main body area 221111, thinned area 221112, insulating layer 22112, adhesive layer 22113, positive electrode tab 2212, negative electrode plate 222, separator 223;

[0032] Controller 200; motor 300. Detailed implementation manners

[0033] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0034] Unless otherwise defined, all technical and scientific terms used in this utility model have the same meaning as commonly understood by those skilled in the technical field to which this utility model belongs; the terms used in the description of the application in this utility model are only for the purpose of describing specific embodiments and are not intended to limit this utility model; the terms "including" and "having" and any variations thereof in the description and claims of this utility model and the above accompanying drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the description and claims of this utility model or the above accompanying drawings are used to distinguish different objects and are not used to describe a specific order or primary-secondary relationship.

[0035] Reference to "embodiment" in this utility model means that a specific feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of this utility model. The phrase appearing in various positions in the description does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this utility model can be combined with other embodiments.

[0036] In the description of this utility model, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "joined", and "attached" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0037] The term "and / or" in this utility model is only a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this utility model generally represents an "or" relationship between the associated objects before and after.

[0038] The term "plurality" as used in this utility model refers to two or more (including two). Similarly, "multiple groups" refers to two or more groups (including two groups), and "multiple pieces" refers to two or more pieces (including two pieces).

[0039] In the embodiment of this utility model, the battery cell can be a secondary battery, which refers to a battery cell that can be activated by charging to continue use after discharging.

[0040] The battery cell can be a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium-metal battery, a sodium-metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-metal hydride battery, a nickel-cadmium battery, a lead-acid battery, etc., and the embodiments of the present utility model are not limited thereto.

[0041] The battery cell can be in a cylindrical shape, a flat shape, a cuboid shape or other shapes, etc., and the embodiments of the present utility model are not limited thereto. Generally, the battery cells are divided into three types according to the packaging method: cylindrical battery cells, square battery cells and soft-pack battery cells, and the embodiments of the present utility model are not limited thereto.

[0042] The battery cell includes a housing, an electrode assembly and an electrolyte, and the housing is used to accommodate the electrode assembly and the electrolyte. The electrode assembly is composed of a positive electrode plate, a negative electrode plate and a separator. The battery cell mainly works by the movement of metal ions between the positive electrode plate and the negative electrode plate. The positive electrode plate includes a positive current collector and a positive coating layer. The positive current collector includes a positive current collector body and a positive tab. The positive coating layer is coated on the surface of the positive current collector body, and the positive tab is not coated with the positive coating layer and protrudes from the positive current collector body. 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 cobaltate, lithium iron phosphate, ternary lithium or lithium manganate, etc. The negative electrode plate includes a negative current collector and a negative coating layer. The negative current collector includes a negative current collector body and a negative tab. The negative coating layer is coated on the surface of the negative current collector body, and the negative tab is not coated with the negative coating layer and protrudes from the negative current collector body. The material of the negative current collector can be copper, and the negative active material can be carbon or silicon, etc. In order to ensure that a large current can pass through without fusing, the number of positive tabs is multiple and stacked together, and the number of negative tabs is multiple and stacked together.

[0043] The material of the separator can be PP (polypropylene) or PE (polyethylene), etc. In addition, the electrode assembly can be a wound structure or a stacked structure, and the embodiments of the present utility model are not limited thereto.

[0044] The technical solutions described in the embodiments of the present utility model are applicable to various electrical devices using battery cells, such as mobile phones, portable devices, laptop computers, battery cars, electric toys, electric tools, vehicles, ships and spacecrafts, etc. For example, spacecrafts include airplanes, rockets, space shuttles and spaceships, etc. The battery cell is used to store or provide electrical energy.

[0045] The inventors found that during the processing of a battery cell with a laminated structure, it is necessary to thin the edge part of the positive electrode plate so that the positive electrode plate and the negative electrode plate can be stacked better during lamination, reducing internal voids and improving space utilization and energy density. However, during the manufacturing process of the electrode assembly, external force interference may cause the positive electrode plate to delaminate and deform in the thinned area from the negative electrode plate, generating gaps, reducing the effective space inside the battery cell, and thus reducing the energy density. Larger gaps may cause the electrode plates to move inside the battery cell, increasing the risk of internal short circuit. Especially during the charging process, if the gap is too large, it may cause an increase in the local current density, thereby increasing the risk of lithium plating.

[0046] Based on the above considerations, in order to solve the problem of the positive electrode plate delaminating and deforming in the thinned area from the negative electrode plate and generating gaps, the inventors conducted in-depth research and designed a battery cell, which includes a housing and an electrode assembly. The electrode assembly is accommodated in the housing and includes electrode plates and a separator. The positive electrode plate among the electrode plates includes a positive current collector body and a positive electrode tab connected to the positive current collector body. A coating layer, an insulating layer, and an adhesive layer are provided on the surface of the positive current collector body. The coating layer includes a main area and a thinned area with a thickness smaller than that of the main area. The thinned area is arranged on both sides of the positive current collector body along the width direction. The insulating layer is arranged on the side of the thinned area away from the main area; at least one insulating layer is bonded to the separator through the adhesive layer.

[0047] In the battery cell with this structure, by providing an adhesive layer on at least one insulating layer, and bonding the insulating layer to the separator through the adhesive layer, the bonding force between the insulating layer of the positive electrode plate and the separator can be increased, thereby effectively reducing the risk of generating gaps between the positive electrode plate and the negative electrode plate, improving the safety performance of the battery cell, and at the same time reducing the internal voids of the battery cell, improving the space utilization and energy density of the battery cell.

[0048] The battery apparatus mentioned in the embodiments of the present utility model may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include a plurality of battery cells, and the plurality of battery cells are connected in series, parallel, or in a hybrid connection through a busbar component.

[0049] In some embodiments, the battery cell assembly is usually formed by arranging a plurality of battery cells.

[0050] As an example, the battery cell assembly may be a battery module, and the battery module is formed by arranging and fixing a plurality of battery cells to form an independent module. As an example, the battery module may be formed by bundling a plurality of battery cells with cable ties.

[0051] In some embodiments, the battery device may be a battery pack, which includes a box body and one or more battery cell assemblies, and the battery cell assemblies are accommodated in the box body.

[0052] As an example, the battery cell assembly may be a battery module, and the battery cell assembly can be accommodated in the box body by fixing the battery module in the box body.

[0053] As an example, the battery cell assembly can also be accommodated in the box body by directly fixing a plurality of battery cells to the box body.

[0054] As an example, the box body may include a first box body and a second box body. The first box body and the second box body are buckled so that a closed space is formed inside the box body to accommodate the battery cell assembly. The "closed" here means covering or closing, which can be sealed or non-sealed. The first box body can be a top cover or a bottom plate.

[0055] As an example, the box body may include a top cover, a frame and a bottom plate. The top cover and the bottom plate are respectively connected to the frame so that a closed space is formed inside the box body to accommodate the battery cell assembly.

[0056] In some embodiments, the box body can be part of the chassis structure of a vehicle. For example, part of the box body can become at least part of the floor of the vehicle, or part of the box body can become at least part of the cross beam and longitudinal beam of the vehicle.

[0057] The technical solutions described in the embodiments of the present utility model are applicable to various electrical devices using battery devices, such as mobile phones, portable devices, laptop computers, battery cars, electric toys, electric tools, vehicles, ships and spacecrafts, etc. For example, spacecrafts include airplanes, rockets, space shuttles and spaceships, etc. The battery device is used to store or provide electric energy.

[0058] The embodiments of the present utility model provide an energy storage device, which includes one or more battery clusters (BatteryCluster) to increase the voltage and capacity of the energy storage device. The battery cluster may include a plurality of battery devices, and the plurality of battery devices are connected in series through a busbar component to increase the voltage of the energy storage device. When the energy storage device includes a plurality of battery clusters, the plurality of battery clusters are connected in parallel to increase the capacity of the energy storage device.

[0059] The energy storage device can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems or temporary power supply systems, etc. The energy storage device can store electric energy as needed and output electric energy at an appropriate time. For example, the energy storage device can store electric energy during the low electricity consumption period and provide electric energy to relevant users or electrical devices during the high electricity consumption period. The energy storage system provided by the embodiments of the present utility model can be any power system that requires an energy storage device.

[0060] In some embodiments, the energy storage device is an energy storage container or an energy storage cabinet.

[0061] In some embodiments, the energy storage device may include a cabinet body and one or more battery clusters, and the battery clusters are accommodated in the cabinet body.

[0062] In some embodiments, the energy storage device may include modules such as a thermal management module, a main control module, a general control module, a power distribution module, and a fire protection module.

[0063] As an example, the thermal management module may include a liquid cooling unit, and the liquid cooling unit provides coolant for adjusting the temperature of battery cells to each battery device through pipelines.

[0064] As an example, the main control module may serve as the battery management unit of the battery cluster for monitoring and managing the battery cluster. The main control module may monitor information such as the current, voltage, power, or temperature of the battery cluster. For example, it can control the charge and discharge current, voltage, etc. of the battery cluster. The main control module includes an auxiliary battery management unit SBMU (Slave Battery Management Unit, SBMU), a fusion switch and other modules.

[0065] As an example, the general control module may serve as the battery management unit of the energy storage device for monitoring and managing the energy storage device. The general control module may monitor information such as the current, voltage, power, state of charge, or temperature of the energy storage device. For example, it can control the charge and discharge current, voltage, etc. of the energy storage device. As an example, the general control module includes an insulation monitoring module IMM (Insulation Monitoring Module, abbreviated as IMM), a main battery management unit MBMU (Master Battery Management Unit, MBMU), an Ethernet ETH (EtherNet, ETH), and a fiber optic conversion module and other modules.

[0066] As an example, the fire protection system includes a control panel, detectors, alarm devices, etc., for detecting, alarming, or extinguishing fires in the energy storage system.

[0067] As an example, the power distribution device can be used to distribute power to the power consumption modules of the energy storage device.

[0068] The technical solutions described in the embodiments of the present invention are applicable to various electrical devices using energy storage devices, such as mobile phones, portable devices, laptop computers, battery cars, electric toys, electric tools, vehicles, ships, and spacecrafts, etc. For example, spacecrafts include airplanes, rockets, space shuttles, and spaceships, etc. The energy storage device is used to store or provide electric energy.

[0069] In some embodiments, such as Figure 1As shown in the figure, the energy storage system may include one or more energy storage devices 1 and a power conversion device 2 (Power Converter System, abbreviated as PCS). The power conversion device 2 is used to connect between the power generation device 3 and the energy storage device 1. The power generation device 3 is used to generate electric energy, and the electric energy generated by the power generation device 3 can be stored in the energy storage device 1 through the power conversion device 2. As an example, the power generation device 3 may specifically be a solar panel, a hydroelectric power generation device, a thermal power generation device, a wind power generation device, etc. Among them, the specific type of the power generation device 3 is not limited in this utility model.

[0070] The technical solutions described in the embodiments of this utility model are applicable to various electrical devices using an energy storage system. For example, mobile phones, portable devices, laptop computers, battery cars, electric toys, electric tools, vehicles, ships, and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles, and spaceships, etc. The energy storage device is used to store or provide electric energy.

[0071] Please refer to Figure 2 , an embodiment of this utility model provides a charging network, which includes a charging pile 4 and an energy storage device 1. The charging pile 4 is electrically connected to the energy storage device 1, and the energy storage device 1 is used to provide electric energy for the charging pile 4. The charging pile 4 and the battery device in the energy storage device 1 are electrically connected through a cable, and the battery device can provide the electric energy stored in itself to the charging pile 4. The charging pile 4 has one or more connectors 5, and the connectors 5 are used to connect to an electrical device (such as a vehicle), so as to replenish energy to the electrical device.

[0072] The energy storage device may be located inside the charging pile (such as an integrated charging and energy storage machine), or outside the charging pile.

[0073] An embodiment of this utility model provides an electrical device using a battery cell or a battery device or an energy storage device or an energy storage system as a power source. The electrical device may be, but is not limited to, mobile phones, tablets, laptop computers, electric toys, electric tools, battery cars, electric vehicles, ships, and spacecraft, etc. Among them, electric toys may include fixed or mobile electric toys, for example, game consoles, electric vehicle toys, electric ship toys, and electric airplane toys, etc. Spacecraft may include airplanes, rockets, space shuttles, and spaceships, etc.

[0074] For the convenience of description in the following embodiments, a vehicle 1000, which is an electrical device in an embodiment of this utility model, is taken as an example for description.

[0075] Please refer to Figure 3 , Figure 3Schematic diagram of the structure of vehicle 1000 provided by some embodiments of the present utility model. Vehicle 1000 can be a fuel vehicle, a gas vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle, an extended-range vehicle, etc. A battery device 100 is provided inside the vehicle. The battery device 100 can be arranged at the bottom, head, or tail of the vehicle. The battery device 100 can be used for power supply of the vehicle. For example, the battery device 100 can be used as the operating power source of the vehicle. The vehicle can also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300. For example, it is used for the working power requirements during the start, navigation, and driving of the vehicle.

[0076] In some embodiments of the present utility model, the battery device 100 can not only be used as the operating power source of the vehicle, but also as the driving power source of the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0077] Please refer to Figure 4 , Figure 4 Exploded view of the structure of the battery device 100 provided by some embodiments of the present utility model. The battery device 100 includes a box body 10 and a plurality of battery cells 20. The battery cells 20 are used to be accommodated in the box body 10. Among them, the box body 10 is used to provide an assembly space for the battery cells 20, and the box body 10 can adopt various structures. In some embodiments, the box body 10 can include a first box body 11 and a second box body 12. The first box body 11 and the second box body 12 are covered with each other, and the first box body 11 and the second box body 12 jointly define an assembly space for accommodating the battery cells 20. The second box body 12 can be a hollow structure with one end open. The first box body 11 can be a plate-like structure. The first box body 11 is covered on the open side of the second box body 12 so that the first box body 11 and the second box body 12 jointly define an assembly space; the first box body 11 and the second box body 12 can also both be hollow structures with one side open, and the open side of the first box body 11 is covered on the open side of the second box body 12. Of course, the box body 10 formed by the first box body 11 and the second box body 12 can be of various shapes, such as a cylinder, a cuboid, etc.

[0078] In the battery device 100, multiple battery cells 20 can be connected in series, parallel, or in a combined series-parallel configuration. A combined series-parallel configuration means that there are both series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 can be directly connected in series, parallel, or in a combined series-parallel configuration together, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10. Of course, the battery device 100 can also be such that multiple battery cells 20 are first connected in series, parallel, or in a combined series-parallel configuration to form a battery module, and then multiple battery modules are connected in series, parallel, or in a combined series-parallel configuration to form a whole and are accommodated in the box 10. The battery device 100 can also include other structures. For example, the battery device 100 can also include a busbar component for realizing the electrical connection among the multiple battery cells 20.

[0079] Please refer to Figure 4 , Figure 4 which is a schematic diagram of a partial structure of the battery device 100 provided in some embodiments of the present invention. The battery device 100 includes multiple rows of battery cells 20 arranged along a first direction, and each row of battery cells 20 includes multiple battery cells 20 arranged along a second direction. The first direction and the second direction are respectively the length direction and the width direction of the box 10, and the first direction and the second direction are perpendicular to each other.

[0080] According to some embodiments of the present invention, referring to Figure 5 and Figure 6 , the present invention provides a battery cell 20, including: a housing and an electrode assembly 22.

[0081] Among them, the electrode assembly 22 can be a wound structure or a stacked structure, and the embodiments of the present invention are not limited thereto.

[0082] The electrode assembly 22 is accommodated in the housing and includes electrode plates and a separator 223. The positive electrode plate 221 among the electrode plates includes a positive electrode current collector body 2211 and a positive electrode tab 2212 connected to the positive electrode current collector body 2211. Refer to Figure 7 and Figure 8 .

[0083] Refer to Figure 6 , Figure 7 and Figure 8 , a coating layer 22111, an insulating layer 22112, and an adhesive layer 22113 are provided on the surface of the positive electrode current collector body 2211.

[0084] Among them, refer to Figure 6 , the insulating layer 22112 is disposed on both sides of the coating layer 22111 along the width direction of the positive electrode current collector body 2211. The insulating layer 22112 is coated on the surface of the positive electrode plate 221, and the adhesive layer 22113 is disposed on the side of the insulating layer 22112 away from the positive electrode current collector body 2211.

[0085] Reference Figure 5 and Figure 6 The coating layer 22111 includes a main body area 221111 and a thinned area 221112 with a thickness smaller than that of the main body area 221111. The thinned area 221112 is disposed on both sides of the positive current collector body 2211 along the width direction, and the insulating layer 22112 is disposed on the side of the thinned area 221112 away from the main body area 221111.

[0086] In this embodiment, by providing the thinned area 221112, the situation where the edge thickness of the positive electrode plate 221 along the width direction is greater than the thickness of the middle area due to surface tension can be reduced, the thickness uniformity of the positive electrode plate 221 can be improved, so that the positive electrode plate 221 can be normally wound, and at the same time, the risk of edge bulging or short circuit that may occur in subsequent processing can be reduced.

[0087] Exemplarily, referring to Figure 5 and Figure 6 on the side surface of the positive current collector body 2211 along the thickness direction, there are arranged in sequence along the width direction of the positive current collector body 2211: an insulating layer 22112, a thinned area 221112, a main body area 221111, a thinned area 221112, and an insulating layer 22112.

[0088] Among them, the thickness of the thinned area 221112 decreases monotonically along the direction from close to far from the main body area 221111. The large end of the thinned area 221112 is connected to the main body area 221111, the small end of the thinned area 221112 is connected to the insulating layer 22112, the side surface of the insulating layer 22112 facing away from the positive current collector body 2211 is aligned with the small end of the thinned area 221112, and the side surface of the main body area 221111 facing away from the positive current collector body 2211 is aligned with the large end of the thinned area 221112.

[0089] The insulating layer 22112 can be an insulating area made of AT11 insulating material. In the case where the un-welded area at the root of the tab is pressed between the positive electrode plate 221 and the negative electrode plate 222, the insulating layer 22112 can reduce the short-circuit risk caused by metal contact between the tab and the coating layer 22111.

[0090] In some embodiments, referring to Figure 7 and Figure 8 the coating film width M1 of the insulating layer 22112 along the width direction of the positive current collector body 2211 satisfies: 5 mm ≤ M1 ≤ 10 mm, and the coating film thickness H2 of the insulating layer 22112 along the thickness direction of the positive current collector body 2211 satisfies: 20 mm ≤ H2 ≤ 50 mm.

[0091] The widths and thicknesses of the insulating layers 22112 of different types of battery cells 20 vary. Exemplarily, the coating width M1 of the insulating layer 22112 along the width direction of the positive current collector body 2211 can be 5 mm, 6 mm, 8 mm, or 10 mm, and the coating thickness H2 of the insulating layer 22112 along the thickness direction of the positive current collector body 2211 can be 20 mm, 26 mm, 38 mm, 45 mm, or 50 mm.

[0092] Among them, referring to Figure 5 and Figure 6 , the adhesive layer 22113 is disposed on the side of the insulating layer 22112 facing away from the positive current collector body 2211, and the adhesive layer 22113 is used to bond the insulating layer 22112 and the separator 223.

[0093] In this embodiment, at least one insulating layer 22112 is bonded to the separator 223 through the adhesive layer 22113, and at least a part of the adhesive layer 22113 is disposed along the thickness direction of the positive current collector body 2211 on the side of the insulating layer 22112 facing the separator 223.

[0094] Among them, the adhesive layer 22113 is disposed on the side of the insulating layer 22112 facing the separator 223 so that at least a part of the insulating layer 22112 is pasted to the separator 223.

[0095] In a battery cell with a single-sided tab, the positive electrode plate 221 includes a tab side and a slitting side facing away from the tab side along the width direction of the positive current collector body 2211. The tab side of the positive electrode plate 221 is the side close to the positive electrode tab, and the slitting side of the positive electrode plate 221 is the side facing away from the positive electrode tab.

[0096] At least one of the insulating layer 22112 on the tab side and the insulating layer 22112 on the slitting side is bonded to the separator 223 through the adhesive layer 22113.

[0097] Among them, the setting method of the adhesive layer 22113 has at least the following multiple methods:

[0098] First, the insulating layer 22112 located between the coating layer 22111 and the positive electrode tab 2212 is bonded to the separator 223 through the adhesive layer 22113.

[0099] In this embodiment, the insulating layer 22112 located between the coating layer 22111 and the positive electrode tab 2212 is bonded to the diaphragm 223, which can seal the insertion entrance of the positive electrode tab 2212, reduce the insertion of the unwelded area at the root of the tab into the interior of the electrode assembly 22, and improve the safety performance of the battery cell 20. At the same time, it can also reduce the entry of welding impurity particles from the tab side into the diaphragm 223 and the positive electrode sheet 221, improve the reliability of the battery cell 20, and at the same time increase the adhesion between the tab side of the positive electrode sheet 221 and the diaphragm 223, thereby effectively reducing the risk of a gap between the positive electrode sheet 221 and the negative electrode sheet 222, improving the safety performance of the battery cell 20, and reducing the internal gap of the battery cell 20, thereby improving the space utilization and energy density of the battery cell 20.

[0100] Second, refer to Figure 5 , Figure 6 and Figure 7 The insulating layers 22112 are disposed on both sides of the coating layer 22111 along the width direction of the positive electrode current collector body 2211 , and the insulating layers 22112 disposed on both sides of the coating layer 22111 are bonded to the separator 223 through the adhesive layer 22113 .

[0101] The tab side and the strip side of the positive electrode sheet 221 are both adhered to the separator 223 .

[0102] In this embodiment, both side ends of the positive electrode sheet 221 along the width direction are bonded to the diaphragm 223. On the first hand, it can reduce the situation where the unwelded area at the root of the pole piece is inserted into the interior of the electrode assembly 22; on the second hand, it can reduce the situation where welding impurity particles enter between the diaphragm 223 and the positive electrode sheet 221, further improving the reliability of the battery cell 20; on the third hand, it can adapt to the battery cell 20 structure with pole pieces on both sides, increasing the usage scenarios; on the fourth hand, it can also increase the bonding force between the two sides of the positive electrode sheet 221 along the width direction and the diaphragm 223, thereby effectively reducing the risk of a gap between the positive electrode sheet 221 and the negative electrode sheet 222, improving the safety performance of the battery cell 20, and at the same time reducing the internal gap of the battery cell 20, thereby improving the space utilization and energy density of the battery cell 20.

[0103] Thirdly, the insulating layer 22112 located on the side of the coating layer 22111 away from the positive electrode tab 2212 is bonded to the diaphragm 223 through the adhesive layer 22113 .

[0104] This embodiment can increase the bonding force between the stripped side of the positive electrode sheet 221 and the diaphragm 223, thereby effectively reducing the risk of a gap between the positive electrode sheet 221 and the negative electrode sheet 222, improving the safety performance of the battery cell 20, and at the same time reducing the internal voids of the battery cell 20, thereby improving the space utilization and energy density of the battery cell 20.

[0105] In some embodiments, with reference to Figure 5 and Figure 6 , the structures on both sides of the positive current collector body 2211 in the thickness direction are the same.

[0106] When the insulating layer 22112 located between the coating layer 22111 and the positive tab 2212 is bonded to the separator 223 through the adhesive layer 22113, both ends of the positive electrode plate 221 along the thickness direction and facing the positive tab 2212 are bonded to the separator 223, thereby further reducing the situation where the un-welded area at the root of the tab is inserted into the inside of the electrode assembly 22. At the same time, it can also reduce the situation where welding impurity particles enter between the separator 223 and the positive electrode plate 221 from the tab side, improving the reliability of the battery cell 20. At the same time, it can also increase the adhesive force between the tab side of the positive electrode plate 221 and the separator 223, thereby effectively reducing the risk of generating a gap between the positive electrode plate 221 and the negative electrode plate 222, improving the safety performance of the battery cell 20, and at the same time reducing the internal voids of the battery cell 20, improving the space utilization rate and energy density of the battery cell 20.

[0107] When the insulating layers 22112 separately provided on both sides of the coating layer 22111 are both bonded to the separator 223 through the adhesive layer 22113, both sides of the positive electrode plate 221 along the thickness direction are bonded to the separator 223, further reducing the situation where welding impurity particles enter between the separator 223 and the positive electrode plate 221, improving the reliability of the battery cell 20; at the same time, it can adapt to the structure of the battery cell 20 with double-sided tabs, increasing the usage scenarios; at the same time, it can also increase the adhesive force between both sides of the positive electrode plate 221 along the width direction and the separator 223, thereby effectively reducing the risk of generating a gap between the positive electrode plate 221 and the negative electrode plate 222, improving the safety performance of the battery cell 20, and at the same time reducing the internal voids of the battery cell 20, improving the space utilization rate and energy density of the battery cell 20.

[0108] When the insulating layer 22112 on the side of the coating layer 22111 facing away from the positive tab 2212 is bonded to the separator 223 through the adhesive layer 22113, both sides of the positive electrode plate 221 along the thickness direction and the ends close to the slitting side can be bonded to the separator 223, thereby effectively reducing the risk of generating a gap between the positive electrode plate 221 and the negative electrode plate 222, improving the safety performance of the battery cell 20, and at the same time reducing the internal voids of the battery cell 20, improving the space utilization rate and energy density of the battery cell 20.

[0109] In the related art, the gap between the positive electrode plate 221 and the negative electrode plate 222 is too large, which may cause uneven distribution of lithium ions during charging, resulting in lithium metal deposition in some areas, that is, the phenomenon of lithium plating. This not only reduces the performance of the battery cell 20, but also may cause safety problems.

[0110] According to the battery cell 20 provided by the embodiments of the present utility model, by providing an adhesive layer 22113 on at least one insulating layer 22112, the insulating layer 22112 is bonded to the separator 223 through the adhesive layer 22113, which can increase the bonding force between the insulating layer 22112 of the positive electrode plate 221 and the separator 223, reduce the risk of deformation of the positive electrode plate 221, thereby effectively reducing the risk of generating a gap between the positive electrode plate 221 and the negative electrode plate 222, improving the safety performance of the battery cell 20, and at the same time reducing the internal voids of the battery cell 20, improving the space utilization rate and energy density of the battery cell 20.

[0111] In some embodiments, the adhesive layer 22113 is a hot melt adhesive layer or a hot melt tape.

[0112] Among them, the glass transition temperature of the hot melt adhesive is between 40 - 200 °C. The hot melt adhesive has the characteristic of melting under heating conditions and can melt and soften its own thickness to bond the separator 223 and the end of the positive electrode plate 221 together, thereby bonding the insulating layer 22112 of the positive electrode plate 221 and the separator 223 to seal the insertion inlet of the positive electrode tab 2212, reducing the situation where the un-welded area at the root of the tab is inserted into the electrode assembly 22. Due to the good adhesiveness and heat resistance of the hot melt adhesive,

[0113] In this embodiment, by using the hot melt adhesive material as the adhesive layer 22113 to bond the insulating layer 22112 and the separator 223, the adhesive layer 22113 can be melted in the hot pressing step to bond the insulating layer 22112 of the positive electrode plate 221 and the separator 223, increasing the bonding force between the insulating layer 22112 of the positive electrode plate 221 and the separator 223, thereby effectively reducing the risk of generating a gap between the positive electrode plate 221 and the negative electrode plate 222. At the same time, the hot melt adhesive material can remain stable in a high-temperature environment, thereby improving the reliable performance of the battery cell 20.

[0114] Among them, the distribution relationship between the adhesive layer 22113 and the insulating layer 22112 at least includes the following three types:

[0115] First, referring to Figure 6 , the orthographic projection of the insulating layer 22112 on the positive electrode current collector body 2211 is located within the orthographic projection of the adhesive layer 22113 on the positive electrode current collector body 2211.

[0116] Among them, the width of the adhesive layer 22113 along the width direction of the positive electrode current collector body 2211 can be greater than or equal to the width of the insulating layer 22112 along the width direction of the positive electrode current collector body 2211, and the length of the adhesive layer 22113 along the length direction of the positive electrode current collector body 2211 can be equal to or greater than the length of the insulating layer 22112 along the length direction of the positive electrode current collector body 2211.

[0117] In other words, the area of the insulating layer 22112 is smaller than that of the adhesive layer 22113. All regions of the insulating layer 22112 can be adhered to the separator 223 through the adhesive layer 22113, further reducing the situation where the un-welded area at the root of the tab is inserted into the interior of the electrode assembly 22. At the same time, it reduces the situation where welding impurity particles enter between the separator 223 and the positive electrode plate 221 from the tab side, improving the reliability of the battery cell 20.

[0118] In some embodiments, referring to Figure 6 , the orthographic projection of the adhesive layer 22113 on the positive electrode current collector body 2211 and the orthographic projection of the coating layer 22111 on the positive electrode current collector body 2211 may have an overlapping area.

[0119] In this embodiment, the adhesive layer 22113 is vitrified during the hot pressing process. The thickness of the adhesive layer 22113 decreases and extends towards the area of the coating layer 22111, increasing the adhesive area between the positive electrode plate 221 and the separator 223, improving the reliability of the adhesion. At the same time, it reduces the distance between the separator 223 and the coating layer 22111, improving the energy density of the battery cell 20.

[0120] In some embodiments, referring to Figure 6 , the orthographic projection of the adhesive layer 22113 on the projection plane along the thickness direction of the positive electrode current collector body 2211 does not overlap with the orthographic projection of the positive electrode tab 2212 on the projection plane along the thickness direction of the positive electrode current collector body 2211.

[0121] In this embodiment, the adhesive layer 22113 does not extend to the surface of the positive electrode tab 2212, thereby reducing the influence on the conductive area of the positive electrode tab 2212.

[0122] Second, referring to Figure 7 , the orthographic projection of the adhesive layer 22113 on the positive electrode current collector body 2211 and the orthographic projection of the insulating layer 22112 on the positive electrode current collector body 2211 have an overlapping area.

[0123] In other words, the orthographic projection of the adhesive layer 22113 on the positive electrode current collector body 2211 and the orthographic projection of the insulating layer 22112 on the positive electrode current collector body 2211 have an intersection.

[0124] Exemplarily, the orthographic projection of the adhesive layer 22113 on the positive electrode current collector body 2211 and the orthographic projection of the coating layer 22111 on the positive electrode current collector body 2211 may have an intersection; or, the orthographic projection of the adhesive layer 22113 on the projection plane along the thickness direction of the positive electrode current collector body 2211 and the orthographic projection of the positive electrode tab 2212 on the projection plane along the thickness direction of the positive electrode current collector body 2211 may have an intersection.

[0125] In this embodiment, the width of the adhesive layer 22113 in the width direction of the positive current collector body 2211 may be smaller than the width of the insulating layer 22112 in the width direction of the positive current collector body 2211, and the length of the adhesive layer 22113 in the length direction of the positive current collector body 2211 may be equal to or greater than the length of the insulating layer 22112 in the length direction of the positive current collector body 2211. This can not only achieve the adhesion between the insulating layer 22112 and the separator 223, but also reduce the amount of hot melt adhesive in the adhesive layer 22113, lower the cost, reduce the risk of the adhesive layer 22113 extending to the positive electrode tab 2212 during the hot pressing process, and at the same time reduce the risk of welding impurities entering the positive electrode plate 221 and the separator 223.

[0126] Thirdly, the orthographic projection of the adhesive layer 22113 on the positive current collector body 2211 may completely coincide with the orthographic projection of the insulating layer 22112 on the positive current collector body 2211.

[0127] Among them, the width of the adhesive layer 22113 in the width direction of the positive current collector body 2211 may be equal to the width of the insulating layer 22112 in the width direction of the positive current collector body 2211, and the length of the adhesive layer 22113 in the length direction of the positive current collector body 2211 may be equal to the length of the insulating layer 22112 in the length direction of the positive current collector body 2211.

[0128] In this embodiment, the adhesion between the entire area of the insulating layer 22112 and the separator 223 can be achieved, further reducing the risk of welding impurities entering the positive electrode plate 221 and the separator 223.

[0129] In this embodiment, the orthographic projection of the adhesive layer 22113 in the thickness direction of the positive current collector body 2211 on the projection plane does not coincide with the orthographic projection of the positive electrode tab 2212 in the thickness direction of the positive current collector body 2211 on the projection plane. The orthographic projection of the adhesive layer 22113 in the thickness direction of the positive current collector body 2211 on the projection plane does not coincide with the orthographic projection of the coating layer 22111 in the thickness direction of the positive current collector body 2211 on the projection plane.

[0130] In some embodiments, referring to Figure 6 , the thickness H1 of the adhesive layer 22113 in the thickness direction of the positive current collector body 2211 satisfies: 10 μm ≤ H1 ≤ 50 μm.

[0131] Exemplarily, the thickness H1 of the adhesive layer 22113 in the thickness direction of the positive current collector body 2211 may be 10 μm, 20 μm, 25 μm, 40 μm or 50 μm, and can be specifically determined according to the type of the battery cell 20.

[0132] In this embodiment, by setting the thickness range of the adhesive layer 22113 along the thickness direction of the positive current collector body 2211, the distance between the separator 223 and the coating layer 22111 on the positive electrode tab 221 can be set, thereby improving the energy density of the battery cell 20.

[0133] In some embodiments, the height h1 of the unilateral adhesive layer 22113 above the main body region 221111 along the thickness direction of the positive current collector body 2211 satisfies: 0 μm ≤ h1 ≤ 10 μm.

[0134] In some embodiments, the height h1 of the unilateral adhesive layer 22113 above the main body region 221111 along the thickness direction of the positive current collector body 2211 satisfies: 5 μm ≤ h1 ≤ 10 μm.

[0135] Exemplarily, the height h1 of the unilateral adhesive layer 22113 above the main body region 221111 along the thickness direction of the positive current collector body 2211 can be 0 μm, 4 μm, 5 μm, 7 μm or 10 μm, and can be specifically determined according to the type of the battery cell 20.

[0136] In this embodiment, the height of the unilateral adhesive layer 22113 above the main body region 221111 along the thickness direction of the positive current collector body 2211 can set the distance between the separator 223 and the coating layer 22111 on the positive electrode tab 221, thereby improving the energy density of the battery cell 20.

[0137] When h1 is 0 μm, the side of the unilateral adhesive layer 22113 facing away from the positive current collector body 2211 is flush with the side of the main body region 221111 facing away from the positive current collector body 2211, which can reduce the internal voids of the battery cell 20 and improve the space utilization rate and energy density of the battery cell 20.

[0138] When h1 > 0 μm, the height of the unilateral adhesive layer 22113 above the main body region 221111 along the thickness direction of the positive current collector body 2211 can increase the adhesion between the tab side of the positive electrode tab 221 and the separator 223, thereby effectively reducing the risk of generating a gap between the positive electrode tab 221 and the negative electrode tab 222 and improving the safety performance of the battery cell 20.

[0139] In some embodiments, it satisfies: 100 μm ≤ H1 + H2 ≤ 110 μm, where H1 is the thickness of the adhesive layer 22113 along the thickness direction of the positive current collector body 2211, and H2 is the thickness of the insulating layer 22112 along the thickness direction of the positive current collector body 2211.

[0140] Exemplarily, the sum of H1 and H2 can be 100 μm, 101 μm, 105 μm, 108 μm or 110 μm, and can be specifically determined according to the type of the battery cell 20.

[0141] In this embodiment, by setting the sum range of the thicknesses of the adhesive layer 22113 and the insulating layer 22112 in the thickness direction of the positive current collector body 2211, the thicknesses of the adhesive layer 22113 and the insulating layer 22112 can be set, and the distance between the separator 223 and the coating layer 22111 on the positive electrode tab 221 can be set, thereby improving the energy density of the battery cell 20.

[0142] In some embodiments, referring to Figure 7 , the difference n1 between the length of the insulating layer 22112 in the length direction of the positive current collector body 2211 and the length of the adhesive layer 22113 in the length direction of the positive current collector body 2211 satisfies: 0 mm ≤ n1 ≤ 2 mm.

[0143] In some embodiments, the difference n1 between the length of the insulating layer 22112 in the length direction of the positive current collector body 2211 and the length of the adhesive layer 22113 in the length direction of the positive current collector body 2211 satisfies: 1 mm ≤ n1 ≤ 2 mm.

[0144] Exemplarily, n1 can be 0 mm, 0.5 mm, 0.8 mm or 1 mm. By setting the range of the difference in the lengths of the insulating layer 22112 and the adhesive layer 22113 in the length direction of the positive current collector body 2211, the adhesion length between the insulating layer 22112 and the separator 223 in the length direction of the positive current collector body 2211 can be increased, thereby reducing the situation where the un-welded area at the root of the tab is inserted into the inside of the electrode assembly 22. At the same time, the situation where welding impurity particles enter between the separator 223 and the positive electrode tab 221 from the tab side can also be reduced, improving the reliability of the battery cell 20.

[0145] Referring to Figure 7 , in the case where n1 is 0 mm, the length of the insulating layer 22112 in the length direction of the positive current collector body 2211 is equal to the length of the adhesive layer 22113 in the length direction of the positive current collector body 2211.

[0146] In some embodiments, the length N1 of the adhesive layer 22113 in the length direction of the positive current collector body 2211 satisfies: 3 mm ≤ N1 ≤ 9 mm;

[0147] Exemplarily, N1 can be 3 mm, 6 mm, 7 mm or 9 mm, and can be specifically determined according to the type and specifications of the battery cell 20.

[0148] In some embodiments, the difference m2 between the width of the insulating layer 22112 in the width direction of the positive current collector body 2211 and the width of the adhesive layer 22113 in the width direction of the positive current collector body 2211 satisfies: 0 mm ≤ m2 ≤ 2 mm.

[0149] In some embodiments, the difference m2 between the width of the insulating layer 22112 in the width direction of the positive current collector body 2211 and the width of the adhesive layer 22113 in the width direction of the positive current collector body 2211 satisfies: 1 mm ≤ m2 ≤ 2 mm;

[0150] Exemplarily, m2 can be 0 mm, 1.1 mm, 1.2 mm or 2 mm, and can be specifically determined according to the type and specifications of the battery cell 20.

[0151] When m2 is 0 mm, the width of the insulating layer 22112 in the width direction of the positive current collector body 2211 is equal to the width of the adhesive layer 22113 in the width direction of the positive current collector body 2211.

[0152] In some embodiments, the thickness difference h2 between the adhesive layers 22113 disposed on both sides of the coating layer 22111 in the thickness direction of the positive current collector body 2211 satisfies: 0 μm ≤ h2 ≤ 3 μm.

[0153] Exemplarily, h2 can be 0 mm, 0.5 mm, 1.5 mm or 3 mm, and can be specifically determined according to the type and specifications of the battery cell 20.

[0154] In this embodiment, by setting the thickness difference between the adhesive layers 22113 disposed on both sides of the coating layer 22111 in the thickness direction of the positive current collector body 2211, the processing difficulty can be reduced.

[0155] In some embodiments, the side surface of the adhesive layer 22113 facing away from the insulating layer 22112 is flush with the side surface of the main body region 221111 facing away from the positive current collector body 2211, so that the separator 223 contacts the side surface of the main body region 221111 facing away from the positive current collector body 2211, thereby increasing the energy density of the battery cell 20 and reducing the risk of deformation of the positive electrode plate 221.

[0156] Wherein, the sum of the thicknesses of the adhesive layer 22113 and the insulating layer 22112 in the thickness direction of the positive current collector body 2211 is equal to the thickness of the main body region 221111 in the thickness direction of the positive current collector body 2211.

[0157] Refer to Figure 5 and Figure 6, according to some embodiments of the present utility model, the present utility model provides a battery cell 20. The battery cell 20 includes a housing and an electrode assembly 22. The electrode assembly 22 is accommodated in the housing and includes electrode plates and a separator 223. The positive electrode plate 221 among the electrode plates includes a positive current collector body 2211 and a positive electrode tab 2212 connected to the positive current collector body 2211. A coating layer 22111, an insulating layer 22112, and an adhesive layer 22113 are provided on the surface of the positive current collector body 2211. The coating layer 22111 includes a main area 221111 and a thinned area 221112 with a thickness smaller than that of the main area 221111. The thinned areas 221112 are arranged on both sides of the positive current collector body 2211 in the width direction. The insulating layer 22112 is provided on the side of the thinned area 221112 away from the main area 221111; at least one insulating layer 22112 is bonded to the separator 223 through the adhesive layer 22113.

[0158] The side of the adhesive layer 22113 facing away from the insulating layer 22112 is flush with the side of the main area 221111 facing away from the positive current collector body 2211.

[0159] In the battery cell 20 with such a structure, by providing the adhesive layer 22113 on at least one insulating layer 22112 and bonding at least one insulating layer 22112 to the separator 223 through the adhesive layer 22113, the adhesive layer 22113 can be melted in the hot pressing step so that the insulating layer 22112 of the positive electrode plate 221 is bonded to the separator 223, increasing the bonding force between the insulating layer 22112 of the positive electrode plate 221 and the separator 223. Thus, the risk of generating a gap between the positive electrode plate 221 and the negative electrode plate 222 is effectively reduced, the safety performance of the battery cell 20 is improved, and at the same time, the internal voids of the battery cell 20 are reduced, improving the space utilization rate and energy density of the battery cell 20.

[0160] According to some embodiments of the present utility model, the present utility model also provides a processing method for a battery cell 20, including:

[0161] Step 1: Provide a positive electrode plate 221. The positive electrode plate 221 includes a positive current collector body 2211 and a positive electrode tab 2212 connected to the positive current collector body 2211. A coating layer 22111 and an insulating layer 22112 are provided on the surface of the positive current collector body 2211. The coating layer 22111 includes a main area 221111 and a thinned area 221112 with a thickness smaller than that of the main area 221111. The thinned areas 221112 are arranged on both sides of the positive current collector body 2211 in the width direction. The insulating layer 22112 is provided on the side of the thinned area 221112 away from the main area 221111.

[0162] Step 2, paste a hot-melt tape or coat a hot-melt adhesive on the insulating layer 22112 of the positive electrode tab 221 after die-cutting to form a paste layer 22113.

[0163] Step 3, then stack the positive electrode tab 221 with the paste layer 22113 formed thereon, the separator 223, and the negative electrode tab 222 in a normal manner.

[0164] According to some embodiments of the present invention, the present invention further provides a battery device 100, and the battery device 100 includes a plurality of battery cells 20.

[0165] According to the battery cell 20 provided by the embodiments of the present invention, by providing the paste layer 22113 on the insulating layer 22112 between the coating layer 22111 and the positive electrode tab 2212 of the positive electrode tab 221, on the premise of reducing the performance impact of the coating layer 22111 of the positive electrode tab 221, the insulating layer 22112 of the positive electrode tab 221 can be bonded to the separator 223, thereby reducing the situation where the un-welded area at the root of the tab is inserted into the electrode assembly 22, and improving the safety performance of the battery cell 20.

[0166] According to some embodiments of the present invention, the present invention further provides an energy storage device 1. The energy storage device 1 includes a plurality of battery cells 20 according to any of the above solutions, and the battery cells 20 are used to store or provide electric energy; or the energy storage device 1 includes a plurality of battery devices 100 according to any of the above solutions, and the battery devices 100 are used to store or provide electric energy.

[0167] According to some embodiments of the present invention, the present invention further provides an energy storage system, and the energy storage system includes: a power conversion device 2 and the energy storage device 1 according to any of the above solutions, and the power conversion device 2 is used to electrically connect a power generation device 3 and the energy storage device 1.

[0168] According to some embodiments of the present invention, the present invention further provides an electrical device. The electrical device includes a plurality of battery cells 20 according to any of the above solutions, and the battery cells 20 are used to store or provide electric energy; or the electrical device includes a plurality of battery devices 100 according to any of the above solutions, and the battery devices 100 are used to store or provide electric energy; or the electrical device includes a plurality of energy storage devices 1 according to any of the above solutions, and the battery cells 20 or the battery devices 100 are used to store or provide electric energy; or the electrical device includes a plurality of energy storage systems according to any of the above solutions, and the battery cells 20 or the battery devices 100 are used to store or provide electric energy.

[0169] The electrical device may be any of the foregoing devices or systems using the battery device 100.

[0170] According to some embodiments of the present utility model, the present utility model further provides a charging network, which includes a charging pile 4 and the energy storage device 1 or the energy storage system according to any of the above solutions. The energy storage device 1 is used to provide electric energy for the charging pile 4.

[0171] The energy storage device 1 can be located inside the charging pile 4 (such as an integrated charging and energy storage machine), or can be located outside the charging pile 4.

[0172] If there is no special description, all implementation manners and optional implementation manners of the present utility model can be combined with each other to form a new technical solution.

[0173] If there is no special description, all technical features and optional technical features of the present utility model can be combined with each other to form a new technical solution.

[0174] The above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. For those skilled in the art, the present utility model can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A battery cell, characterized in that, Comprising: A housing; An electrode assembly, accommodated within the housing, including electrode plates and a separator. The positive electrode plate among the electrode plates includes a positive current collector body and a positive electrode tab connected to the positive current collector body. A coating layer, an insulating layer, and an adhesive layer are provided on the surface of the positive current collector body. The coating layer includes a main region and a thinned region with a thickness smaller than that of the main region. The thinned region is disposed on both sides of the positive current collector body along the width direction. The insulating layer is disposed on a side of the thinned region away from the main region; at least one of the insulating layers is bonded to the separator through the adhesive layer.

2. The battery cell according to claim 1, wherein A side surface of the adhesive layer facing away from the insulating layer is flush with a side surface of the main region facing away from the positive current collector body.

3. The battery cell according to claim 1, characterized in that, A positive projection of the insulating layer on the positive current collector body is located within a positive projection of the adhesive layer on the positive current collector body.

4. The battery cell according to claim 3, wherein, The positive projection of the adhesive layer on the positive current collector body and the positive projection of the coating layer on the positive current collector body have an overlapping region.

5. The battery cell according to claim 3, characterized in that, A positive projection of the adhesive layer along the thickness direction of the positive current collector body on a projection plane does not overlap with a positive projection of the positive electrode tab along the thickness direction of the positive current collector body on the projection plane.

6. The battery cell according to claim 1, characterized in that, The insulating layers located on both sides of the coating layer are both bonded to the separator through the adhesive layer.

7. The battery cell according to claim 1, characterized in that, Satisfying: 0μm ≤ h1 ≤ 10μm, where h1 is the height of the adhesive layer on one side along the thickness direction of the positive current collector body and higher than the main region; and / or, Satisfying: 1mm ≤ n1 ≤ 2mm, where n1 is the difference between the length of the insulating layer along the length direction of the positive current collector body and the length of the adhesive layer along the length direction of the positive current collector body.

8. The battery cell according to any one of claims 1-7, characterized in that, The adhesive layer is a hot melt adhesive layer or a hot melt tape.

9. A battery device, characterized in that, Comprising: A plurality of battery cells according to any one of claims 1 - 8.

10. An energy storage device, characterized in that, Comprising: A plurality of battery cells according to any one of claims 1 - 8 or a plurality of battery devices according to claim 9, where the battery cells or the battery devices are used for storing or providing electrical energy.

11. An electrical device, characterized in that, Comprising: A battery cell according to any one of claims 1 - 8, a battery device according to claim 9, or an energy storage device according to claim 10, where the battery cell or the battery device is used for storing or providing electrical energy.

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