A battery cell, a battery device, and an electric device

Abstract

The application discloses a battery monomer, a battery device and a power utilization device, and belongs to the technical field of batteries. The battery monomer comprises a shell, an electrode terminal, an electrode assembly and an adhesive. The electrode terminal is arranged in the shell. The electrode assembly is located in the shell and is electrically connected with the electrode terminal. The electrode assembly comprises a positive electrode sheet, a negative electrode sheet and a separator arranged between the positive electrode sheet and the negative electrode sheet. The electrode assembly has a flat area. The arrangement direction of the positive electrode sheet and the negative electrode sheet in the flat area is a preset direction. The adhesive is attached to the electrode assembly. The adhesive comprises a first adhesive sub-component. The first adhesive sub-component has a first weakened hole. The first adhesive sub-component is attached to an end surface of the electrode assembly. The end surface is located between side surfaces on opposite sides of the electrode assembly along the preset direction. The first adhesive sub-component is arranged across the positive electrode sheet and the negative electrode sheet along the preset direction. The first weakened hole arranged on the first adhesive sub-component reduces metal deposits on the negative electrode sheet of the battery monomer.

Description

Technical Field

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

[0002] Batteries are being used more and more widely in life and industry. For example, new energy vehicles equipped with batteries have been widely used. In addition, batteries are also being increasingly used in energy storage fields.

[0003] In the related art, metal deposits may exist on the negative electrode plate of a battery cell. Summary of the Invention

[0004] To solve the above technical problems, the present disclosure provides a battery cell, a battery device, and an electrical device to reduce metal deposits on the negative electrode sheet of the battery cell.

[0005] This application is implemented through the following technical solutions.

[0006] An embodiment of the present application provides a battery cell, comprising:

[0007] shell;

[0008] an electrode terminal, disposed on the housing;

[0009] an electrode assembly, located within the housing and electrically connected to the electrode terminal, the electrode assembly comprising a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive electrode sheet and the negative electrode sheet, the electrode assembly having a flat region, the positive electrode sheet and the negative electrode sheet being arranged in a predetermined direction within the flat region;

[0010] An adhesive component is bonded to the electrode assembly, and the adhesive component includes a first adhesive sub-component, the first adhesive sub-component has a first weakened hole, the first adhesive sub-component is attached to the end face of the electrode assembly, the end face is located between the side faces of the electrode assembly on opposite sides along the preset direction, and the first adhesive sub-component is arranged across the positive electrode sheet and the negative electrode sheet along the preset direction.

[0011] In the embodiment of the present disclosure, since the first adhesive sub-component is arranged across the positive electrode plate and the negative electrode plate along the preset direction, the first adhesive sub-component bears the expansion force mainly along the preset direction during the expansion process of the electrode assembly. A first weakening hole is provided on the first adhesive sub-component to reduce the strength of the first adhesive sub-component and the overall restraining ability of the adhesive on the electrode assembly, which is conducive to releasing the expansion of the electrode assembly to a certain extent and reducing the expansion force inside the electrode assembly, thereby alleviating the precipitation of metal ions and correspondingly reducing the metal deposits on the negative electrode plate.

[0012] In some embodiments, the first weakened hole penetrates the first adhesive sub-component along an arrangement direction of the electrode assembly and the corresponding first adhesive sub-component.

[0013] In the disclosed embodiment, a first weakened hole extends through the first adhesive sub-component along the arrangement direction of the electrode assembly and the corresponding first adhesive sub-component, allowing electrolyte to penetrate between the positive and negative electrode sheets of the electrode assembly through the first weakened hole in the first adhesive sub-component. Furthermore, gases generated by the positive and / or negative electrode sheets during the charge and discharge process are discharged from between the positive and negative electrode sheets and out of the electrode assembly through the first weakened hole in the first adhesive sub-component. The first weakened hole not only reduces the binding of the adhesive on the electrode assembly but also provides a corresponding channel for electrolyte to penetrate the electrode assembly and for exhaust during the charge and discharge process of the electrode assembly, thereby facilitating electrolyte penetration between the positive and negative electrode sheets and improving exhaust.

[0014] In some embodiments, the first adhesive sub-component is shaped like a sheet structure, and the directions intersecting the preset direction and the thickness direction of the first adhesive sub-component are target directions. The thickness direction of the first adhesive sub-component is intersecting the preset direction, and the sum of the dimensions of the remaining parts of the first adhesive sub-component except the first weakened hole along the target direction is greater than or equal to 3 mm.

[0015] In the embodiment of the present disclosure, for the first adhesive sub-component of the sheet structure, since the target direction is arranged crosswise with the preset direction and the thickness direction of the first adhesive sub-component, the sum of the dimensions of the remaining parts of the first adhesive sub-component except the first weakened hole along the target direction is more important for the bearing capacity of the first adhesive sub-component against expansion force. The sum of the dimensions of the remaining parts of the first adhesive sub-component except the first weakened hole along the target direction is greater than or equal to 3 mm, so that the sum of the dimensions of the remaining parts of the first adhesive sub-component except the first weakened hole along the target direction is more appropriate, and the possibility of the first adhesive sub-component breaking at the first weakened hole is reduced while reducing the strength of the adhesive as much as possible and reducing the binding ability of the adhesive on the electrode assembly.

[0016] In some embodiments, a thickness direction of the first adhesive sub-component is perpendicular to the preset direction, and the target direction is perpendicular to the preset direction and the thickness direction of the first adhesive sub-component, respectively.

[0017] In the embodiment of the present disclosure, since the target direction is basically perpendicular to the main direction of action of the expansion force of the electrode assembly, and the target direction is perpendicular to the second direction, the sum of the dimensions of the remaining parts of the first adhesive sub-component except the first weakened hole along the target direction is compared with the sum of the dimensions of the remaining parts of the first adhesive sub-component except the first weakened hole along other directions. Under the condition that the size values ​​are the same, limiting the sum of the dimensions of the remaining parts of the first adhesive sub-component except the first weakened hole along the target direction makes the first adhesive sub-component have a stronger bearing capacity, which is beneficial to reduce the possibility of the first adhesive sub-component breaking at the first weakened hole.

[0018] In some embodiments, the adhesive component further includes a second adhesive sub-component, and the side surfaces of the electrode assembly on two opposite sides along the preset direction are both adhered with the second adhesive sub-components, and the first adhesive sub-component is connected between the second adhesive sub-components on both sides.

[0019] In the embodiment of the present disclosure, since the positive electrode sheet and the negative electrode sheet are arranged along a preset direction, the second adhesive sub-component is adhered to the side surfaces of the electrode assembly on opposite sides along the preset direction, so that the second adhesive sub-component can be in contact with the surface of the electrode assembly as much as possible, and the second adhesive sub-component and the electrode assembly can be adhered more firmly.

[0020] In some embodiments, the second adhesive sub-component has a second weakened hole, and the second weakened hole penetrates the second adhesive sub-component along the thickness direction of the second adhesive sub-component; or, the second adhesive sub-component is separated at two opposite sides along a preset direction.

[0021] In the disclosed embodiment, a second weakened hole is provided in the second adhesive sub-component, correspondingly weakening the strength of the adhesive at the location of the second adhesive sub-component. Perforations can be performed throughout the entire raw material used to make the adhesive. When cutting the raw material to obtain the corresponding adhesive, there is no need to identify which locations on the raw material are weakened by the first weakened hole and which are not. Any section of the raw material can serve as either the first or second adhesive sub-component, thereby increasing the versatility of the adhesive and the raw material used to make the adhesive. The second adhesive sub-component is separated along two opposing sides of a predetermined direction, and substantially no holes are provided on the second adhesive sub-component connecting the two opposing sides of the second adhesive sub-component along the predetermined direction. This facilitates increasing the contact area between the second adhesive sub-component and the electrode assembly, resulting in a more secure bond between the second adhesive sub-component and the electrode assembly.

[0022] In some embodiments, the direction that intersects the preset direction and the thickness direction of the first adhesive sub-component is the target direction, the thickness direction of the first adhesive sub-component intersects the preset direction, and the sum of the dimensions of the remaining parts of the second adhesive sub-component except the second weakened hole along the target direction is greater than or equal to 3 mm.

[0023] In the embodiment of the present disclosure, the sum of the dimensions of the remaining parts of the second adhesive sub-component except the second weakened hole along the target direction is greater than or equal to 3 mm, so that the sum of the dimensions of the remaining parts of the second adhesive sub-component except the second weakened hole along the target direction is relatively appropriate, which can reduce the possibility of the second adhesive sub-component breaking at the second weakened hole. For adhesive components that require the first adhesive sub-component to reduce breakage, the first adhesive sub-component and the second adhesive sub-component can be used interchangeably. In the process of cutting the raw materials for making adhesive components to obtain adhesive components, there is no need to identify which position is used for the first adhesive component and which position is used for the second adhesive component, which is conducive to improving the versatility of adhesive components and the raw materials for making adhesive components.

[0024] In some embodiments, the positive electrode sheet, the negative electrode sheet, and the separator are wound together into a wound structure, and the electrode assembly and the first adhesive sub-component are arranged along the axial direction of the winding axis of the electrode assembly.

[0025] In the embodiment of the present disclosure, the electrode assembly and the first adhesive component are arranged along the axial direction of the winding axis of the electrode assembly, and the adhesive component on at least one side of the electrode assembly along the axial direction of the winding axis can better restrain the positive electrode sheet and the negative electrode sheet of the wound electrode assembly.

[0026] In some embodiments, the adhesive members are provided on opposite sides of the electrode assembly along the axial direction of the winding axis.

[0027] In the embodiment of the present disclosure, among the adhesives on both sides, the adhesives on each side respectively restrain the electrode assembly from the corresponding side of the electrode assembly along the axial direction of the winding axis, so that the positive electrode sheet along one side of the axial direction of the winding axis and the corresponding side of the negative electrode sheet along the axial direction of the winding axis can be close to each other, and the other side of the positive electrode sheet along the axial direction of the winding axis and the other side of the negative electrode sheet along the axial direction of the winding axis can be close to each other, and the opposite sides of the electrode assembly along the axial direction of the winding axis can be better restrained by the corresponding adhesives.

[0028] In some embodiments, the adhesive on one side is a first adhesive, the positive electrode sheet has a positive electrode ear, the negative electrode sheet has a negative electrode ear, the positive electrode ear and the negative electrode ear are electrically connected to the corresponding electrode terminals, respectively, the first adhesive, the positive electrode ear and the negative electrode ear are all located on the same side of the electrode assembly along the axial direction of the winding axis, and the first adhesive is located between the positive electrode ear and the negative electrode ear.

[0029] In the embodiment of the present disclosure, the first adhesive is located between the positive electrode ear and the negative electrode ear, which can fully utilize the space between the positive electrode ear and the negative electrode ear to arrange the first adhesive, and the positive electrode ear and the negative electrode ear located on the same side of the electrode assembly along the axial direction of the winding axis are separated by a certain distance, which is conducive to better insulation between the positive electrode ear and the negative electrode ear.

[0030] In some embodiments, at least two of the adhesive members on the other side are second adhesive members, and at least two of the second adhesive members are arranged at intervals.

[0031] In the embodiment of the present disclosure, at least two adhesives on the other side can constrain different positions on the corresponding side of the electrode assembly, which is beneficial for constraining the corresponding side of the electrode assembly more evenly while minimizing the amount of adhesives used.

[0032] The present disclosure provides a battery device including the battery cell according to any one of the above embodiments.

[0033] The present disclosure provides an electrical device, comprising a battery cell according to any one of the above embodiments or a battery device according to any one of the above embodiments, wherein the battery cell or the battery device is used to store or provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference numerals are used throughout the drawings to denote the same components. In the drawings:

[0035] Figure 1 Schematic diagram of the structure of the electric device according to an embodiment of the present disclosure;

[0036] Figure 2 An exploded view of a battery device according to an embodiment of the present disclosure;

[0037] Figure 3 This is an exploded view of a battery cell according to an embodiment of the present disclosure, in which adhesive components are not shown;

[0038] Figure 4 This is an assembly diagram of the electrode assembly and the adhesive member according to an embodiment of the present disclosure, in which the first weakened hole is not shown;

[0039] Figure 5 Schematic diagram of the electrode assembly and adhesive components in the exploded state according to an embodiment of the present disclosure, in which a first weakened hole is provided on the first adhesive component and a second weakened hole is provided on the second adhesive component;

[0040] Figure 6 for Figure 5 Magnified view at position A;

[0041] Figure 7 Schematic diagram of the electrode assembly and adhesive components in the exploded state according to an embodiment of the present disclosure, wherein a first weakened hole is provided on the first adhesive component, and no hole is provided on the second adhesive component;

[0042] Figure 8 for Figure 7 Magnified view at position B in the middle;

[0043] Figure 9 A view of the electrode assembly and the adhesive member according to an embodiment of the present disclosure projected along the second direction;

[0044] Figure 10 for Figure 9 Magnified view at position C in the middle;

[0045] Figure 11 Schematic diagram of the structure of a wound electrode assembly according to an embodiment of the present disclosure;

[0046] Figure 12 This is a schematic structural diagram of a laminated electrode assembly according to an embodiment of the present disclosure, in which adhesive components are not shown.

[0047] Figure 13 for Figure 12 D-direction view in FIG, in which the adhesive member and the electrode assembly are arranged along the first direction;

[0048] Figure 14 for Figure 12 In the D-direction view, the adhesive and the electrode assembly are arranged along the second direction.

[0049] Description of Reference Numerals

[0050] 1000. Vehicle; 100. Battery device; 200. Controller; 300. Motor; 400. Housing; 401. First housing; 402. Second housing; 500. Battery cell; 1. Casing; 11. Shell; 12. End cap; 2. Electrode terminal; 3. Electrode assembly; 31. Positive electrode sheet; 312. Positive electrode tab; 32. Negative electrode sheet; 322. Negative electrode tab; 33. Isolator; 34. Straight area; 35. Corner area; 41. First adhesive component; 42. Second adhesive component; 43. First adhesive sub-component; 431. First weakened hole; 44. Second adhesive sub-component; 441. Second weakened hole; 45. Third adhesive component; 5. Insulating film; 6. Reference line; R1. Preset direction; R2. Axial direction of winding axis; R3. Reference direction; R4. First direction; R5. Second direction. DETAILED DESCRIPTION

[0051] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are for the purpose of describing specific embodiments only and are not intended to limit this application; the terms "including" and "having" of the embodiments of the present disclosure and any variations thereof are intended to cover non-exclusive inclusions.

[0053] In the description of the embodiments of this application, the technical terms "first," "second," "third," etc. are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise specifically defined.

[0054] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0055] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0056] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0057] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, the technical term "contact" should be understood in a broad sense, and can be direct contact, contact through an intermediate medium layer, contact with essentially no interaction force between the two contacting parties, or contact with interaction force between the two contacting parties.

[0058] In the related art, an electrode assembly includes a positive electrode sheet, a negative electrode sheet, and a separator. A separator is provided between the positive electrode sheet and the negative electrode sheet. The electrode assembly has a flat region. The positive electrode sheet and the negative electrode sheet are arranged in a predetermined direction within the flat region. A first adhesive sub-component bonded to the electrode assembly is provided on the end face of the electrode assembly. The adhesive constrains the electrode assembly by applying tension in the predetermined direction, so that the positive electrode sheet, the negative electrode sheet, and the separator of the electrode assembly are as close as possible, reducing the gap between the positive electrode sheet, the negative electrode sheet, and the separator, and reducing the thickness of the electrode assembly so that the electrode assembly can be better inserted into the shell. However, due to the high strength of the adhesive, when the electrode assembly expands during the charge and discharge process, the adhesive has a strong ability to constrain the electrode assembly, generating a large expansion force inside the electrode assembly. The large expansion force causes more metal ions to precipitate and deposit on the negative electrode sheet, resulting in a large amount of metal deposits on the negative electrode sheet.

[0059] For example, if the battery cell is a lithium-ion battery, the large expansion force inside the electrode assembly may aggravate the damage of the SEI film (Solid Electrolyte Interface) or cause changes in the microstructure of the negative electrode material, resulting in obstruction of lithium ion transmission and lithium deposition. More lithium ions are deposited and form more lithium metal deposits on the negative electrode sheet.

[0060] In the embodiments of the present application, by arranging weakened holes in the first adhesive component, the strength of the first adhesive component is reduced, which in turn reduces the strength of the adhesive component and reduces the adhesive's restraint on the electrode assembly. This can, to a certain extent, release the expansion of the electrode assembly and reduce the expansion force within the electrode assembly, thereby alleviating metal ion precipitation and correspondingly reducing metal deposits on the negative electrode sheet. For example, this can alleviate lithium deposition within a battery cell.

[0061] The solution in which the first adhesive component of the embodiment of the present application has the first weakened hole can be used not only in battery cells, but also in battery devices and electrical devices.

[0062] The present application embodiment provides an electrical device, see Figure 1 , including battery cells or battery devices, which are used to store or provide electrical energy.

[0063] In some embodiments, the power-consuming device further includes a device body, and the battery device is installed in the device body to supply power to the device body.

[0064] An electrical device is a device that uses electricity as an energy source and consumes it to achieve its corresponding function. For example, an electrical device may include, but is not limited to, a mobile phone, tablet computer, laptop computer, electric toy, power tool, battery-powered vehicle, electric vehicle, ship, spacecraft, etc. Electric toys may include fixed or mobile electric toys, such as game consoles, electric vehicle toys, electric ship toys, and electric aircraft toys. Spacecraft may include airplanes, rockets, space shuttles, and spacecraft, etc.

[0065] The "device body" refers to the main structure that consumes electrical energy to perform its corresponding functions. For example, a power-consuming device could be a mobile phone, where the "device body" is the portion that performs functions such as communication, and power is supplied to this portion via a battery cell or battery device. For example, a power-consuming device could be a car, where the "device body" is the portion that provides passengers with a seat and allows them to travel on the road, and power is supplied to this portion via a battery cell or battery device.

[0066] The electrical device in some embodiments of the present application is taken as an example of a vehicle 1000 .

[0067] The vehicle 1000 provided in some embodiments of the present application may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended range vehicle. Figure 1 The vehicle 1000 is provided with a battery device 100. The battery device 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000. For example, the battery device 100 can serve as an operating power source for the vehicle 1000. The vehicle 1000 can also include a controller 200 and a motor 300. The controller 200 can be used to control the battery device 100 to power the motor 300. For example, the battery device 100 can be used to meet the power requirements of the vehicle 1000 during startup, navigation, and driving.

[0068] In some embodiments of the present application, the battery device 100 can serve not only as an operating power source for the vehicle 1000 , but also as a driving power source for the vehicle 1000 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000 .

[0069] In some embodiments, the battery device 100 may be a battery pack.

[0070] In some embodiments, the battery device 100 may be an energy storage device.

[0071] The battery device 100 of the embodiment of the present application includes a battery cell 500. The battery cell 500 is used to store or provide electrical energy.

[0072] At least two battery cells 500 in the battery device are connected in series, in parallel, or in a mixed connection.

[0073] In the embodiment of the present application, the battery cell 500 may be a secondary battery. A secondary battery refers to a battery cell 500 that can be continuously used by activating active materials by charging after the battery cell 500 is discharged.

[0074] The battery cell 500 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-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc., which is not limited in the embodiments of the present application.

[0075] The battery cell 500 includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator, with the separator being positioned between the negative and positive electrodes. During the charge and discharge process of the battery cell 500, active ions (e.g., lithium ions) are intercalated and released between the positive and negative electrodes. The separator is positioned between the positive and negative electrodes to prevent short circuits between the positive and negative electrodes while allowing active ions to pass through. In some embodiments, the positive electrode can be a positive electrode plate, which can include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0076] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is provided on either or both of the two facing surfaces of the positive electrode current collector.

[0077] As examples, the positive electrode current collector can be made of metal foil, conductive polymer material, carbon material, or composite current collector. For example, the metal foil can be made of pure metals, alloys, or surface-treated metals, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. A composite current collector can include a polymer base layer and a metal layer. The composite current collector can be formed by forming a metal material (such as aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys) onto a polymer substrate (such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0078] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium-containing phosphates may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 )、LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 )、LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 )、LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM 622 )、LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.8 Co 0.15 Al 0.05 O2) and at least one of its modified compounds. Modified compounds refer to substances obtained by modifying the above substances through methods such as doping or coating.

[0079] For some examples, see Figure 2 The battery device 100 further includes a box body 400 , and the battery cells 500 are installed in the box body 400 .

[0080] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0081] As examples, the negative electrode current collector can be made of metal foil, conductive polymer material, carbon material, or composite current collector. For example, the metal foil can be made of pure metal, alloy, or surface-treated metal, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. A composite current collector can include a polymer base layer and a metal layer. The composite current collector can be formed by forming a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy) on a polymer substrate (such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0082] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0083] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is provided on either or both of the two facing surfaces of the negative electrode current collector.

[0084] As an example, the negative electrode active material may adopt the negative electrode active material for the battery cell 500 that is well known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for the battery cell 500 may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0085] In some embodiments, the negative electrode may be a metal foam. The metal foam may be nickel foam, copper foam, aluminum foam, or alloy foam. When the metal foam is used as the negative electrode, the surface of the metal foam may or may not be provided with a negative electrode active material.

[0086] In some embodiments, the negative electrode may be made of carbon foam.

[0087] As an example, the negative electrode active material may be filled and / or deposited in the negative electrode current collector.

[0088] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0089] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0090] In some embodiments, the separator is a separator. The present application has no particular limitation on the type of separator, and any known separator with a porous structure having good chemical and mechanical stability can be selected.

[0091] As an example, the primary material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separator can be a separate component located between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes. The surface of the separator can also be coated with an inorganic particle coating, an organic particle coating, or an organic / inorganic composite coating.

[0092] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transport ions and isolate the positive and negative electrodes.

[0093] In some embodiments, the battery cell 500 further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not specifically limit the type of electrolyte, and the electrolyte may be selected based on needs. The electrolyte may be liquid, gel, or solid.

[0094] The liquid electrolyte includes an electrolyte salt and a solvent.

[0095] In some embodiments, the electrolyte salt may be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalatoborate, lithium dioxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0096] In some embodiments, the solvent can be selected from at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, cyclopentane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent can also be an ether solvent. Ether solvents can include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether and crown ether.

[0097] In some embodiments, the electrolyte may optionally include additives. For example, the additives may include negative electrode film-forming additives, positive electrode film-forming additives, or additives capable of improving certain properties of the battery cell 500, such as additives that improve the overcharge / fast charge performance of the battery cell 500, additives that improve the high-temperature performance of the battery cell 500, and additives that improve the low-temperature performance of the battery cell 500.

[0098] Among them, the gel electrolyte includes a polymer as a skeleton network and can be used in combination with an ionic liquid-lithium salt.

[0099] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0100] As an example, the polymer of the polymer solid electrolyte may include polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, a single ion polymer, a polyionic liquid, cellulose, and the like.

[0101] As an example, the inorganic solid electrolyte can be an oxide solid electrolyte (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superion conductor (lithium germanium phosphosulfide, silver germanium sulfide), amorphous sulfide) and one or more of a halide solid electrolyte, a nitride solid electrolyte and a hydride solid electrolyte.

[0102] As an example, a composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0103] The electrode assembly may be a wound structure, a laminated structure, or a mixed structure of wound and laminated structures.

[0104] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0105] In some embodiments, the electrode assembly is a laminate structure.

[0106] As an example, multiple positive electrode sheets and multiple negative electrode sheets can be provided respectively, and the multiple positive electrode sheets and the multiple negative electrode sheets can be alternately stacked.

[0107] As an example, multiple positive electrode sheets may be provided, and the negative electrode sheet is folded to form multiple stacked folded segments, with a positive electrode sheet sandwiched between adjacent folded segments.

[0108] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of stacked folded segments.

[0109] As an example, multiple separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0110] As an example, the separator may be provided continuously, and may be provided between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0111] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0112] In some embodiments, the electrode assembly is provided with tabs that can conduct current from the electrode assembly. The tabs include a positive tab and a negative tab.

[0113] In some embodiments, see Figure 2 The battery device 100 further includes a box body 400 , and the battery cells 500 are installed in the box body 400 .

[0114] As an example, housing 400 may include a first housing 401 and a second housing 402. The first housing 401 and the second housing 402 engage to form an enclosed space within housing 400 for accommodating battery cell assemblies. Enclosed here means covered or closed, and can be either sealed or unsealed. First housing 401 may be a top cover or a bottom plate.

[0115] The battery cell 500 of the embodiment of the present application is shown in FIG. Figures 3 to 5 , Figure 7 , Figure 11 and Figure 12 The battery cell 500 includes a housing 1, an electrode terminal 2, an electrode assembly 3, and an adhesive. The electrode terminal 2 is disposed in the housing 1. The electrode assembly 3 is located within the housing 1 and is electrically connected to the electrode terminal 2. The electrode assembly 3 includes a positive electrode sheet 31, a negative electrode sheet 32, and a separator 33 disposed between the positive electrode sheet 31 and the negative electrode sheet 32. The electrode assembly 3 has a straight region 34, and the positive electrode sheet 31 and the negative electrode sheet 32 ​​are arranged in a predetermined direction R1 within the straight region 34. The adhesive is bonded to the electrode assembly 3 and includes a first adhesive sub-component 43. The first adhesive sub-component 43 has a first weakened hole 431. The first adhesive sub-component 43 is attached to the end face of the electrode assembly 3, which is located between the side faces of the electrode assembly 3 on opposite sides along the predetermined direction R1. The first adhesive sub-component 43 spans the positive electrode sheet 31 and the negative electrode sheet 32 ​​along the predetermined direction R1.

[0116] The first adhesive sub-component 43 is attached to the end face of the electrode assembly 3 and projected along the arrangement direction of the electrode assembly 3 and the corresponding first adhesive sub-component 43. The orthographic projection area of ​​the first adhesive sub-component 43 is located within the orthographic projection area of ​​the electrode assembly 3. The arrangement direction of the electrode assembly 3 and the corresponding first adhesive sub-component 43 is arranged crosswise with the preset direction R1.

[0117] For example, see Figure 4 、 Figure 5 and Figure 7 ,as well as Figures 9 to 11 The positive electrode sheet 31, the negative electrode sheet 32, and the separator 33 are wound together into a wound structure. The electrode assembly 3 and the first adhesive sub-component 43 are arranged along the axial direction R2 of the winding axis. The first adhesive sub-component 43 is attached to the end surface of the electrode assembly 3. When projected along the axial direction R2 of the winding axis, the orthographic projection area of ​​the first adhesive sub-component 43 is located within the orthographic projection area of ​​the electrode assembly 3. The axial direction R2 of the winding axis is arranged to intersect the preset direction R1.

[0118] Exemplarily, the arrangement direction of the electrode assembly 3 and the corresponding first adhesive sub-component 43 is perpendicular to the preset direction R1.

[0119] Exemplarily, the axial direction R2 of the winding axis is perpendicular to the preset direction R1.

[0120] For example, see Figure 12 、 Figure 13 and Figure 14 The positive electrode sheet 31, the negative electrode sheet 32, and the separator 33 are stacked in sequence to form a laminated structure. The electrode assembly 3 is a laminated electrode assembly 3. The electrode assembly 3 and the electrode terminal 2 are arranged in a first direction R4. The first direction R4 intersects the preset direction R1. The direction intersecting the preset direction R1 and the first direction R4 is a second direction R5.

[0121] Exemplarily, the first direction R4 is perpendicular to the preset direction R1 , the second direction R5 is perpendicular to the preset direction R1 , and the first direction R4 is perpendicular to the second direction R5 .

[0122] For example, see Figure 13 and Figure 14 The adhesive bonded to the laminated electrode assembly 3 is the third adhesive 45 .

[0123] For example, see Figure 13 The electrode assembly 3 and the first adhesive sub-component 43 corresponding to the third adhesive component 45 are arranged along the first direction R4.

[0124] For example, see Figure 14 The electrode assembly 3 and the first adhesive sub-component 43 corresponding to the third adhesive component 45 are arranged along the second direction R5.

[0125] The first adhesive sub-component 43 is arranged across the positive electrode sheet 31 and the negative electrode sheet 32 ​​along the preset direction R1. Along the arrangement direction of the electrode assembly 3 and the corresponding first adhesive sub-component 43, at least part of the orthographic projection area of ​​at least one positive electrode sheet 31 and at least part of the orthographic projection area of ​​at least one negative electrode sheet 32 ​​are located within the orthographic projection area of ​​the first adhesive sub-component 43.

[0126] The outer shell 1 is mainly used to accommodate the electrode assembly 3 and protect the electrode assembly 3.

[0127] The electrode terminal 2 is electrically connected to the electrode assembly 3 , and the electrode assembly 3 is charged through the electrode terminal 2 or the electrode assembly 3 is discharged through the electrode terminal 2 .

[0128] Exemplarily, the electrode terminal 2 may be a pole.

[0129] Exemplarily, the isolation member 33 may be an isolation film.

[0130] Illustratively, the separator 33 may be partially or entirely disposed between the positive electrode sheet 31 and the negative electrode sheet 32 ​​.

[0131] Illustratively, the positive electrode sheet 31 , the negative electrode sheet 32 ​​and the separator 33 are stacked in sequence to form a laminate structure, and the electrode assembly 3 is a laminated electrode assembly 3 .

[0132] For the laminated electrode assembly 3 , the entire electrode assembly 3 is substantially located in the flat region 34 .

[0133] Exemplarily, the positive electrode sheet 31 , the negative electrode sheet 32 ​​and the separator 33 are wound together to form a wound structure, and the electrode assembly 3 is a wound electrode assembly 3 .

[0134] Exemplarily, for the wound electrode assembly 3, the electrode assembly 3 also has a corner area 35, and a corner area 35 is provided on both opposite sides of the straight area 34. The arrangement direction of the corner areas 35 on both sides is the reference direction R3, and the reference direction R3 is respectively arranged to cross the preset direction R1 and the axial direction R2 of the winding axis.

[0135] Exemplarily, the reference direction R3 is perpendicular to the preset direction R1 , and the reference direction R3 is perpendicular to the axial direction R2 of the winding axis.

[0136] Illustratively, the adhesive member may be an adhesive tape.

[0137] Exemplarily, the adhesive member may be adhesive tape.

[0138] Illustratively, the adhesive member may be a structure formed by curing an adhesive.

[0139] The first adhesive component 43 is attached to the end surface of the electrode assembly 3 and is arranged across the positive electrode sheet 31 and the negative electrode sheet 32 ​​along the predetermined direction R1. The expansion force generated during the expansion of the electrode assembly 3 is mainly applied in the predetermined direction R1, and the expansion force mainly in the predetermined direction R1 is borne by the first adhesive component 43.

[0140] Illustratively, projected along the arrangement direction of the electrode assembly 3 and the corresponding first adhesive sub-component 43 , the orthographic projection area of ​​the first adhesive sub-component 43 spans the orthographic projection areas of at least two positive electrode sheets 31 and the orthographic projection areas of at least two negative electrode sheets 32 .

[0141] Illustratively, projected along the arrangement direction of the electrode assembly 3 and the corresponding first adhesive component 43 , the orthographic projection area of ​​the first adhesive component 43 spans the orthographic projection areas of all the positive electrode sheets 31 and the orthographic projection areas of all the negative electrode sheets 32 .

[0142] For example, the battery cell 500 is a lithium-ion battery, and providing the first weakened hole 431 on the first adhesive component 43 is beneficial to alleviating lithium deposition in the battery cell 500 and reducing lithium metal deposits on the negative electrode plate 32 .

[0143] For example, see Figure 3 The battery cell 500 further includes an insulating film 5, and the electrode assembly 3 is at least partially located within the space enclosed by the insulating film 5. The first adhesive component 43 on the end surface of the electrode assembly 3 can constrain the separator 33 to a certain extent, reducing the possibility that the portion of the separator 33 protruding from the positive electrode tab 31 and the negative electrode tab 32 will fall between the electrode assembly 3 and the insulating member, thereby facilitating the thermal fusion of the insulating film 5.

[0144] Exemplarily, the insulating film 5 may be a Mylar film.

[0145] For example, see Figure 3 The outer shell 1 includes a shell 11 and an end cover 12 covered on the shell 11 , the electrode assembly 3 is located in a space enclosed by the shell 11 and the end cover 12 , the shell 11 is connected to the end cover 12 , and the electrode terminal 2 is provided on the end cover 12 .

[0146] In the embodiment of the present disclosure, since the first adhesive sub-component 43 is attached to the end surface of the electrode assembly 3, the first adhesive sub-component 43 is arranged across the positive electrode plate 31 and the negative electrode plate 32 along the preset direction R1. The first adhesive sub-component 43 bears the expansion force of the electrode assembly 3 mainly along the preset direction R1 during the expansion process. A first weakening hole 431 is provided on the first adhesive sub-component 43 to reduce the strength of the first adhesive sub-component 43 and the overall restraining ability of the adhesive on the electrode assembly 3, which is conducive to releasing the expansion of the electrode assembly 3 to a certain extent and reducing the expansion force inside the electrode assembly 3, thereby alleviating the precipitation of metal ions and correspondingly reducing the metal deposits on the negative electrode plate 32.

[0147] In some embodiments, see Figures 5 to 8The first weakened hole 431 penetrates the first adhesive component 43 along the arrangement direction of the electrode assembly 3 and the corresponding first adhesive component 43. The electrolyte can penetrate between the positive electrode sheet 31 and the negative electrode sheet 32 ​​roughly along the arrangement direction of the electrode assembly 3 and the corresponding first adhesive component 43.

[0148] The gas generated by the positive electrode sheet 31 and / or the negative electrode sheet 32 ​​during the charge and discharge process is discharged from the electrode assembly 3 from between the positive electrode sheet 31 and the negative electrode sheet 32 ​​approximately along the arrangement direction of the electrode assembly 3 and the corresponding first adhesive component 43 .

[0149] Exemplarily, the first adhesive component 43 is sheet-shaped, and the first weakened hole 431 penetrates the first adhesive component 43 along the thickness direction of the first adhesive component 43, and the thickness direction of the first adhesive component 43 is along the arrangement direction of the electrode assembly 3 and the corresponding first adhesive component 43.

[0150] For example, the shape of the first weakened hole 431 may be circular, polygonal, or elliptical.

[0151] In the disclosed embodiment, the first weakened hole 431 extends through the first adhesive sub-component 43 along the arrangement direction of the electrode assembly 3 and the corresponding first adhesive sub-component 43, allowing electrolyte to penetrate between the positive electrode sheet 31 and the negative electrode sheet 32 ​​of the electrode assembly 3 through the first weakened hole 431 in the first adhesive sub-component 43. Furthermore, gases generated by the positive electrode sheet 31 and / or the negative electrode sheet 32 ​​during the charge and discharge process are discharged from between the positive electrode sheet 31 and the negative electrode sheet 32 ​​and out of the electrode assembly 3 through the first weakened hole 431 in the first adhesive sub-component 43. The first weakened hole 431 not only reduces the constraint of the adhesive on the electrode assembly 3 but also provides a corresponding channel for electrolyte to penetrate the electrode assembly 3 and for gas to be exhausted during the charge and discharge process of the electrode assembly 3, thereby facilitating the electrolyte to penetrate between the positive electrode sheet 31 and the negative electrode sheet 32 ​​and effectively exhausting the gas.

[0152] It is understood that the specific structure of the first weakened hole 431 is not limited. For example, the first weakened hole 431 can be a blind hole with one end open and the other end closed, as long as it can reduce the strength of the first adhesive component 43 and reduce the adhesive's ability to restrain the electrode assembly 3.

[0153] In some embodiments, see Figure 9 and Figure 10 The first adhesive sub-component 43 is shaped like a sheet structure, and the directions intersecting the preset direction R1 and the thickness direction of the first adhesive sub-component 43 are target directions. The thickness direction of the first adhesive sub-component 43 intersects the preset direction R1, and the sum of the dimensions of the remaining parts of the first adhesive sub-component 43 except the first weakened hole 431 along the target direction is greater than or equal to 3 mm.

[0154] For example, see Figure 13 For a laminated electrode assembly, the arrangement direction of the electrode assembly 3 and the first adhesive sub-component 43 corresponding to the third adhesive component 45 is arranged along the first direction R4, and the target direction is arranged along the second direction R5.

[0155] For example, see Figure 14 For a laminated electrode assembly, the arrangement direction of the electrode assembly 3 and the first adhesive sub-component 43 corresponding to the third adhesive component 45 is arranged along the second direction R5, and the target direction is arranged along the first direction R4.

[0156] For example, see Figure 4 、 Figure 5 、 Figure 7 、 Figures 9 to 11 For the wound electrode assembly 3, the electrode assembly 3 and the first adhesive component 43 are arranged along the axial direction R2 of the winding axis, and the target direction is arranged along the reference direction R3.

[0157] Exemplarily, the first adhesive sub-component 43 is in a sheet shape, and the thickness direction of the first adhesive sub-component 43 is arranged along the arrangement direction of the electrode assembly 3 and the corresponding first adhesive sub-component 43 .

[0158] The first adhesive sub-component 43 is in a sheet-like structure, and the dimension of the first adhesive sub-component 43 in the thickness direction is relatively small.

[0159] For example, the surfaces of the first adhesive sub-component 43 of the sheet-like structure on two opposite sides along the thickness direction may be planes.

[0160] The preset direction R1 , the thickness direction of the first adhesive component 43 , and the target direction are arranged to intersect each other. The preset direction R1 , the thickness direction of the first adhesive component 43 , and the target direction intersect each other and are not coplanar.

[0161] The sum of the dimensions of the remaining parts of the first adhesive sub-component 43 except the first weakened hole 431 along the target direction, that is, the sum of the dimensions of the physical part of the first adhesive sub-component 43 without the first weakened hole 431 along the target direction, specifically, it can be the sum of the hole spacing between each adjacent two first weakened holes 431 on the first adhesive sub-component 43 and the hole margin of the first weakened hole 431 close to the edge of the first adhesive sub-component 43.

[0162] For example, see Figure 9 and Figure 10In the figure, the first weakened holes 431 are arranged in a matrix of five rows and six columns. The first weakened holes 431 are circular in shape. The straight line coinciding with the center of the first weakened holes 431 and extending along the target direction is the reference line 6. The target direction is shown in the figure along the reference direction R3, which is the arrangement direction of the corner areas 35 on both sides. The intersection of the reference line 6 and the first weakened holes 431 is the preset intersection point. The distance between two adjacent preset intersection points on two adjacent first weakened holes 431 is the hole spacing. The distance between the preset intersection point on the first weakened hole 431 closest to the edge of the first adhesive sub-component 43 and the intersection point formed by the reference line 6 and the edge contour of the first adhesive sub-component 43 is the hole margin distance. Along the target direction, the hole spacings between each adjacent first weakened hole 431 are L2, L3, L4 and L5 respectively, and the hole margins on both sides are L1 and L6 respectively. The sum of the dimensions of the remaining part of the first adhesive sub-component 43 except the first weakened hole 431 along the target direction is L1+ L2+L3+L4+L5+ L6, that is, L1+ L2+L3+L4+L5+ L6≥3mm.

[0163] For example, the sum of the dimensions of the remaining portion of the first adhesive component 43 excluding the first weakened hole 431 along the target direction may be 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm.

[0164] Exemplarily, the sum of the dimensions of the remaining portion of the first adhesive component 43 excluding the first weakened hole 431 along the target direction is greater than or equal to 5 mm.

[0165] In the embodiment of the present disclosure, for the first adhesive sub-component 43 of the sheet structure, since the target direction is arranged to cross the preset direction R1 and the thickness direction of the first adhesive sub-component 43, the sum of the dimensions of the remaining parts of the first adhesive sub-component 43 except the first weakened hole 431 along the target direction is more important for the bearing capacity of the first adhesive sub-component 43 against the expansion force. The sum of the dimensions of the remaining parts of the first adhesive sub-component 43 except the first weakened hole 431 along the target direction is greater than or equal to 3 mm, so that the sum of the dimensions of the remaining parts of the first adhesive sub-component 43 except the first weakened hole 431 along the target direction is more appropriate, while reducing the strength of the adhesive as much as possible and reducing the binding ability of the adhesive on the electrode assembly 3, the possibility of the first adhesive sub-component 43 breaking at the first weakened hole 431 is reduced.

[0166] It is understood that the sum of the dimensions of the first adhesive component 43 excluding the first weakened hole 431 along the target direction is not limited. For example, the sum of the dimensions of the first adhesive component 43 excluding the first weakened hole 431 along the target direction can be slightly less than 3 mm.

[0167] In some embodiments, see Figure 4 、 Figure 5 、 Figure 7 、 Figure 9 and Figure 10 The thickness direction of the first adhesive component 43 is perpendicular to the preset direction R1, and the target direction is perpendicular to the preset direction R1 and the thickness direction of the first adhesive component 43 respectively.

[0168] The target direction is perpendicular to the preset direction R1 , and the target direction is substantially perpendicular to the main acting direction of the expansion force of the electrode assembly 3 .

[0169] In the embodiment of the present disclosure, since the target direction is basically perpendicular to the main direction of action of the expansion force of the electrode assembly 3, and the target direction is perpendicular to the thickness direction of the first adhesive sub-component 43, the sum of the dimensions of the remaining parts of the first adhesive sub-component 43 except the first weakened hole 431 along the target direction is compared with the sum of the dimensions of the remaining parts of the first adhesive sub-component 43 except the first weakened hole 431 along other directions. When the size values ​​are the same, limiting the sum of the dimensions of the remaining parts of the first adhesive sub-component 43 except the first weakened hole 431 along the target direction makes the first adhesive sub-component 43 have a stronger bearing capacity, which is beneficial to reduce the possibility of the first adhesive sub-component 43 breaking at the first weakened hole 431.

[0170] It is understood that the arrangement of the directions is not limited. For example, the thickness direction of the first adhesive component 43 intersects with the preset direction R1 but is not perpendicular to it. The target direction intersects with the preset direction R1 and the thickness direction of the first adhesive component 43 but is not perpendicular to it.

[0171] In some embodiments, see Figures 5 to 8 The adhesive component also includes a second adhesive sub-component 44. The side surfaces of the electrode assembly 3 on both sides along the preset direction R1 are adhered with the second adhesive sub-components 44, and the first adhesive sub-component 43 is connected between the second adhesive sub-components 44 on both sides.

[0172] For example, the first adhesive sub-component 43 and the second adhesive sub-component 44 may be integrally formed.

[0173] Illustratively, the first adhesive component 43 includes a first main colloid and a first adhesive layer arranged on one side of the first main colloid, and the second adhesive component 44 includes a second main colloid and a second adhesive layer arranged on one side of the second main colloid. The first main colloid and the second main colloid can be integrally formed.

[0174] For example, the first adhesive component 43 and the second adhesive component 44 may be bonded to each other.

[0175] For example, the first adhesive sub-component 43 and the second adhesive sub-component 44 may be connected by other detachable or non-detachable connection methods other than bonding or integral molding.

[0176] In the embodiment of the present disclosure, since the positive electrode plate 31 and the negative electrode plate 32 are arranged along the preset direction R1, the second adhesive sub-component 44 is adhered to the side surfaces of the electrode assembly 3 on opposite sides along the preset direction R1, so that the second adhesive sub-component 44 can be in contact with the ground of the electrode assembly 3 as much as possible, and the second adhesive sub-component 44 and the electrode assembly 3 can be adhered relatively firmly.

[0177] It is understandable that the specific structure of the adhesive component is not limited. For example, the adhesive component may include the first adhesive component 43 but not the second adhesive component 44.

[0178] In some embodiments, see Figure 5 and Figure 6 The second adhesive sub-component 44 has a second weakened hole 441 , and the second weakened hole 441 penetrates the second adhesive sub-component 44 along the thickness direction of the second adhesive sub-component 44 .

[0179] For example, the shape of the second weakened hole 441 may be the same as or different from the shape of the first weakened hole 431 .

[0180] Exemplarily, the shape of the second weakened hole 441 may be circular, polygonal, or elliptical.

[0181] In the embodiment of the present disclosure, a second weakened hole 441 is provided on the second adhesive sub-component 44, and the strength of the adhesive at the position of the second adhesive sub-component 44 is correspondingly weakened. Punching can be performed on the entire raw material for making the adhesive. In the process of cutting the raw material for making the adhesive to obtain the corresponding adhesive, there is no need to identify which positions on the raw material for making the adhesive are weakened by the first weakened hole 431 and which positions are not weakened. Any section on the raw material for making the adhesive can be used as the first adhesive sub-component 43 or the second adhesive sub-component 44, thereby improving the versatility of the adhesive and the raw material for making the adhesive.

[0182] In some embodiments, see Figure 7 and Figure 8 , the second adhesive sub-components 44 are separated on two opposite sides along the preset direction R1.

[0183] The second adhesive component 44 is separated on two opposite sides along the preset direction R1 , which means that there is no opening on the second adhesive component 44 , and the two opposite sides along the preset direction R1 are not connected through the through hole on the second adhesive component 44 .

[0184] In the embodiment of the present disclosure, the second adhesive sub-component 44 is separated on opposite sides along the preset direction R1, and there are basically no holes on the second adhesive sub-component 44 that connect the opposite sides of the second adhesive sub-component 44 along the preset direction R1, which is beneficial to increase the contact area between the second adhesive sub-component 44 and the electrode assembly 3, so that the second adhesive sub-component 44 and the electrode assembly 3 are more firmly bonded.

[0185] In some embodiments, see Figure 5 and Figure 6 , the directions intersecting the preset direction R1 and the thickness direction of the first adhesive sub-component 43 are the target directions, the thickness direction of the first adhesive sub-component 43 intersects the preset direction R1, and the sum of the dimensions of the remaining parts of the second adhesive sub-component 44 except the second weakened hole 441 along the target direction is greater than or equal to 3 mm.

[0186] The sum of the dimensions of the remaining parts of the second adhesive sub-component 44 except the second weakened hole 441 along the target direction, that is, the sum of the dimensions of the physical part of the second adhesive sub-component 44 without the second weakened hole 441 along the target direction, specifically, it can be the sum of the hole spacing between each adjacent second weakened hole 441 on the second adhesive sub-component 44 and the hole margin of the second weakened hole 441 close to the edge of the second adhesive sub-component 44.

[0187] For example, the sum of the dimensions of the remaining portion of the first adhesive component 43 excluding the first weakened hole 431 along the target direction may be 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm.

[0188] Illustratively, the sum of the dimensions of the second adhesive component 44 excluding the second weakened hole 441 along the target direction is greater than or equal to 3 mm, and the sum of the dimensions of the first adhesive component 43 excluding the first weakened hole 431 along the target direction is greater than or equal to 3 mm.

[0189] Exemplarily, the sum of the dimensions of the remaining portion of the second adhesive component 44 excluding the second weakened hole 441 along the target direction is greater than or equal to 5 mm.

[0190] Illustratively, the sum of the dimensions of the second adhesive component 44 excluding the second weakened hole 441 along the target direction is greater than or equal to 5 mm, and the sum of the dimensions of the first adhesive component 43 excluding the first weakened hole 431 along the target direction is greater than or equal to 5 mm.

[0191] In the embodiment of the present disclosure, the sum of the dimensions of the remaining parts of the second adhesive sub-component 44 except the second weakened hole 441 along the target direction is greater than or equal to 3 mm, so that the sum of the dimensions of the remaining parts of the second adhesive sub-component 44 except the second weakened hole 441 along the target direction is relatively appropriate, which can reduce the possibility of the second adhesive sub-component 44 breaking at the second weakened hole 441. For adhesives that have the need to reduce the breakage of the first adhesive sub-component 43, the first adhesive sub-component 43 and the second adhesive sub-component 44 can be used interchangeably. In the process of cutting the raw materials for making adhesives to obtain adhesives, there is no need to identify which position is used for the first adhesive component 41 and which position is used for the second adhesive component 42, which is conducive to improving the versatility of adhesives and the raw materials for making adhesives.

[0192] It is understood that the sum of the dimensions of the second adhesive component 44 excluding the second weakened hole 441 along the target direction is not limited. For example, the sum of the dimensions of the second adhesive component 44 excluding the second weakened hole 441 along the target direction can be slightly less than 3 mm.

[0193] In some embodiments, see Figure 4 、 Figure 5 and Figure 7 The positive electrode sheet 31 , the negative electrode sheet 32 ​​and the separator 33 are wound together into a wound structure, and the electrode assembly 3 and the first adhesive sub-component 43 are arranged along the axial direction of the winding axis of the electrode assembly 3 .

[0194] For example, the negative electrode sheet 32 ​​, the separator 33 , the positive electrode sheet 31 and the separator 33 may be stacked in sequence and then wound as a whole to obtain the wound electrode assembly 3 .

[0195] In the embodiment of the present disclosure, the electrode assembly 3 and the first adhesive component 43 are arranged along the axial direction of the winding axis of the electrode assembly 3, and the adhesive component on at least one side of the electrode assembly 3 along the axial direction of the winding axis can better restrain the positive electrode sheet 31 and the negative electrode sheet 32 ​​of the wound electrode assembly 3.

[0196] In some embodiments, see Figure 4 、 Figure 5 and Figure 7 Adhesive members are provided on opposite sides of the electrode assembly 3 along the axial direction R2 of the winding axis.

[0197] An adhesive is provided on one side of the electrode assembly 3 along the axial direction R2 of the winding axis, and an adhesive is provided on the other side of the electrode assembly 3 along the axial direction R2 of the winding axis.

[0198] In the embodiment of the present disclosure, among the adhesives on both sides, the adhesives on each side respectively restrain the electrode assembly 3 from the corresponding side along the axial direction of the winding axis, so that the positive electrode sheet 31 on one side along the axial direction of the winding axis and the corresponding side of the negative electrode sheet 32 ​​along the axial direction of the winding axis can be close to each other, and the positive electrode sheet 31 on the other side along the axial direction of the winding axis and the negative electrode sheet 32 ​​on the other side along the axial direction of the winding axis can be close to each other, and the opposite sides of the electrode assembly 3 along the axial direction of the winding axis can be better restrained by the corresponding adhesives.

[0199] It is understood that the arrangement of the adhesive is not limited. For example, the adhesive is located on one side of the electrode assembly 3 along the axial direction of the winding axis, and no adhesive is provided on the other side of the electrode assembly 3 along the axial direction of the winding axis.

[0200] In some embodiments, see Figure 4 、 Figure 5 and Figure 7 , one side of the adhesive is the first adhesive 41, the positive electrode sheet 31 has a positive electrode ear 312, the negative electrode sheet 32 ​​has a negative electrode ear 322, the positive electrode ear 312 and the negative electrode ear 322 are respectively electrically connected to the corresponding electrode terminal 2, the first adhesive 41, the positive electrode ear 312 and the negative electrode ear 322 are all located on the same side of the electrode assembly 3 along the axial direction of the winding axis, and the first adhesive 41 is located between the positive electrode ear 312 and the negative electrode ear 322.

[0201] The positive electrode tab 312 is electrically connected to the corresponding electrode terminal 2 so that the polarity of the corresponding electrode terminal 2 is positive.

[0202] The negative electrode tab 322 is electrically connected to the corresponding electrode terminal 2 so that the polarity of the corresponding electrode terminal 2 is negative.

[0203] Illustratively, the positive tab 312 and the negative tab 322 are arranged along the reference direction R3 .

[0204] In the embodiment of the present disclosure, the first adhesive 41 is located between the positive electrode tab 312 and the negative electrode tab 322, and the space between the positive electrode tab 312 and the negative electrode tab 322 can be fully utilized to arrange the first adhesive 41, and the positive electrode tab 312 and the negative electrode tab 322 located on the same side of the electrode assembly 3 along the axial direction of the winding axis are separated by a certain distance, which is conducive to better insulation between the positive electrode tab 312 and the negative electrode tab 322.

[0205] It is understood that the arrangement of the first adhesive member 41 is not limited. For example, the positive electrode tab 312 is located between the negative electrode tab 322 and the first adhesive member 41 , or the negative electrode tab 322 is located between the positive electrode tab 312 and the first adhesive member 41 .

[0206] In some embodiments, see Figure 4 、 Figure 5 and Figure 7, at least two adhesive members on the other side are second adhesive members 42 , and at least two second adhesive members 42 are arranged at intervals.

[0207] Exemplarily, at least two second adhesive members 42 are arranged along the reference direction R3 .

[0208] In the embodiment of the present disclosure, at least two adhesives on the other side can constrain different positions on the corresponding side of the electrode assembly 3, which is beneficial for constraining the corresponding side of the electrode assembly 3 more evenly while minimizing the amount of adhesives used.

[0209] The present disclosure provides a battery cell 500. Figures 3 to 12 The battery cell 500 includes a housing 1, an electrode terminal 2, an electrode assembly 3, and an adhesive. The electrode terminal 2 is disposed in the housing 1. The electrode assembly 3 is located within the housing 1 and is electrically connected to the electrode terminal 2. The electrode assembly 3 includes a positive electrode sheet 31, a negative electrode sheet 32, and a separator 33. The separator 33 is disposed between the positive electrode sheet 31 and the negative electrode sheet 32. The electrode assembly 3 has a straight region 34. The positive electrode sheet 31 and the negative electrode sheet 32 ​​are arranged in a predetermined direction R1 within the straight region 34. The adhesive is bonded to the electrode assembly 3 and includes a first adhesive sub-component 43. The first adhesive sub-component 43 has a first weakened hole 431. The first adhesive sub-component 43 is attached to the end face of the electrode assembly 3. The end face is located between the side faces of the electrode assembly 3 on opposite sides along the predetermined direction R1. The first adhesive sub-component 43 spans the positive electrode sheet 31 and the negative electrode sheet 32 ​​along the predetermined direction R1. The first weakened hole 431 extends through the corresponding first adhesive sub-component 43 along the alignment direction of the electrode assembly 3 and the corresponding first adhesive sub-component 43. The first adhesive sub-component 43 is a sheet-like structure, with the target direction being the direction intersecting the preset direction R1 and the thickness direction of the first adhesive sub-component 43. The sum of the dimensions of the remaining portion of the first adhesive sub-component 43, excluding the first weakened hole 431, along the target direction is greater than or equal to 5 mm. The specific value can be adjusted based on the width and length of the adhesive and is not limited to 5 mm. The adhesive also includes a second adhesive sub-component 44, which is bonded to opposite sides of the electrode assembly 3 along the preset direction R1. The first adhesive sub-component 43 is connected between the second adhesive sub-components 44 on both sides.

[0210] The second adhesive component 44 has a second weakened hole 441 , which penetrates the second adhesive component 44 along the thickness direction of the second adhesive component 44 ; or, the second adhesive component 44 is separated at two opposite sides along the preset direction R1 .

[0211] The first weakened holes 431 may be circular, polygonal, or elliptical, and the second weakened holes 441 may be circular, polygonal, or elliptical. At least two first weakened holes 431 are evenly arranged, and at least two second weakened holes 441 are evenly arranged.

[0212] At least two rows of first weakened holes 431 are aligned. The first weakened holes 431 are distributed in a matrix. At least two rows of second weakened holes 441 are aligned. The second weakened holes 441 are distributed in a matrix.

[0213] At least two rows of first weakened holes 431 are staggered. At least two second weakened holes 441 are staggered.

[0214] The electrode assembly 3 is provided with U-shaped adhesive members along both sides of the winding axis.

[0215] The above embodiments are intended only to illustrate the technical solutions of the present application and are not intended to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they may modify the technical solutions described in the above embodiments or replace some or all of the technical features therein with equivalents. Such modifications or replacements do not deviate from the essence of the corresponding technical solutions within the scope of the technical solutions of the embodiments of the present application. In particular, the various technical features described in the various embodiments may be combined in any manner as long as there are no structural conflicts.

Claims

1. A battery cell, characterized in that: include: shell; an electrode terminal, disposed on the housing; an electrode assembly, located within the housing and electrically connected to the electrode terminal, the electrode assembly comprising a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive electrode sheet and the negative electrode sheet, the electrode assembly having a flat region, the positive electrode sheet and the negative electrode sheet being arranged in a predetermined direction within the flat region; an adhesive member bonded to the electrode assembly, the adhesive member comprising a first adhesive member having a first weakened hole, the first adhesive member being attached to an end face of the electrode assembly, the end face being located between side faces of the electrode assembly on opposite sides along the preset direction, the first adhesive member being arranged across the positive electrode sheet and the negative electrode sheet along the preset direction; The first weakened hole penetrates the first adhesive sub-component along the arrangement direction of the electrode assembly and the corresponding first adhesive sub-component; The first adhesive sub-component is in a sheet-like structure, a direction intersecting the preset direction and the thickness direction of the first adhesive sub-component is a target direction, the thickness direction of the first adhesive sub-component intersects the preset direction, and the sum of the dimensions of the remaining portion of the first adhesive sub-component excluding the first weakened hole along the target direction is greater than or equal to 3 mm; There are multiple first weakened holes, and the multiple first weakened holes are distributed in a matrix.

2. The battery cell according to claim 1, wherein: The thickness direction of the first adhesive component is perpendicular to the preset direction, and the target direction is perpendicular to the preset direction and the thickness direction of the first adhesive component respectively.

3. The battery cell according to claim 1, wherein: The adhesive component further includes a second adhesive sub-component. The second adhesive sub-components are adhered to the side surfaces of the electrode assembly on two opposite sides along the preset direction, and the first adhesive sub-component is connected between the second adhesive sub-components on both sides.

4. The battery cell according to claim 3, characterized in that The second adhesive sub-component has a second weakened hole, which penetrates the second adhesive sub-component along the thickness direction of the second adhesive sub-component. There are multiple second weakened holes, and the multiple second weakened holes are distributed in a matrix; or the second adhesive sub-component is separated on opposite sides along a preset direction.

5. The battery cell according to claim 4, characterized in that The directions respectively intersecting the preset direction and the thickness direction of the first adhesive sub-component are target directions, the thickness direction of the first adhesive sub-component intersecting the preset direction, and the sum of the dimensions of the remaining parts of the second adhesive sub-component except the second weakened hole along the target direction is greater than or equal to 3 mm.

6. The battery cell according to any one of claims 1 to 5, characterized in that: The positive electrode sheet, the negative electrode sheet and the separator are wound together to form a wound structure, and the electrode assembly and the first adhesive sub-component are arranged along the axial direction of the winding axis of the electrode assembly.

7. The battery cell according to claim 6, characterized in that The adhesive members are provided on opposite sides of the electrode assembly along the axial direction of the winding axis.

8. The battery cell according to claim 7, characterized in that The adhesive on one side is a first adhesive, the positive electrode sheet has a positive electrode ear, and the negative electrode sheet has a negative electrode ear. The positive electrode ear and the negative electrode ear are electrically connected to the corresponding electrode terminals respectively. The first adhesive, the positive electrode ear and the negative electrode ear are all located on the same side of the electrode assembly along the axial direction of the winding axis, and the first adhesive is located between the positive electrode ear and the negative electrode ear.

9. The battery cell according to claim 8, characterized in that At least two of the adhesive members on the other side are second adhesive members, and at least two of the second adhesive members are arranged at intervals.

10. A battery device, characterized in that: The invention comprises a battery cell according to any one of claims 1 to 9.

11. An electrical device, characterized in that: The invention comprises a battery cell according to any one of claims 1 to 9 or a battery device according to claim 10, wherein the battery cell or the battery device is used to store or provide electrical energy.

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