Electric device, battery device, battery cell and manufacturing method thereof

Abstract

The invention provides a power utilization device, a battery device, a battery monomer and a manufacturing method of the battery monomer. The battery monomer comprises a shell, an electrode terminal, an electrode assembly, a first insulating part, a current collecting part and a second insulating part, the shell is provided with a first wall, the electrode terminal is arranged on the first wall, and the electrode lug of the electrode assembly is led out from the electrode body along the end part of the thickness direction of the first wall. The first insulating part is arranged on the side, facing the electrode body, of the first wall, and the first insulating part is provided with a boss which protrudes towards the electrode body. The current collector is electrically connected with the tab and the electrode terminal, the welding part of the current collector is in welded connection with the electrode terminal, the boss is located on one side of the welding part in the first direction, and the first direction intersects with the thickness direction. The second insulating part is arranged on the side, facing the electrode body, of the welding part. The orthographic projection of the second insulating part in the first direction is located in the boss. The battery monomer provided by the invention is beneficial to reducing the risk that the second insulating part crushes the electrode assembly, so that the risk of short circuit in the battery monomer is reduced.

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] Battery monomers are widely used in electronic devices, such as mobile phones, laptop computers, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes and electric tools, etc.

[0003] In the development of battery cell technology, in addition to improving the performance of battery cells, the reliability of battery cells is also an issue that needs to be considered. Therefore, how to improve the reliability of battery cells is an issue of continuous improvement in battery device technology. Summary of the invention

[0004] The present application provides a battery cell, a battery device and an electrical device to improve the reliability of the battery cell.

[0005] This application is achieved through the following technical solutions: In the first aspect, the battery cell provided by the embodiment of the present application includes a shell, an electrode terminal, an electrode assembly, a first insulating member, a current collector, and a second insulating member. The shell has a first wall, the electrode terminal is arranged on the first wall, and the electrode assembly includes an electrode body and a pole ear, and the pole ear is led out from the end of the electrode body along the thickness direction of the first wall. The first insulating member is arranged on the side of the first wall facing the electrode body, and the first insulating member has a boss protruding toward the electrode body. The current collector is arranged on the side of the first insulating member facing the electrode body, the current collector electrically connects the pole ear and the electrode terminal, the current collector has a welding portion, the welding portion is welded to the electrode terminal, the boss is located on one side of the welding portion along the first direction, and the first direction intersects with the thickness direction. The second insulating member is arranged on the side of the welding portion facing the electrode body, and the orthographic projection of the second insulating member along the first direction is located within the boss.

[0006] The battery cell provided in the embodiment of the present application is configured such that the orthographic projection of the second insulating member along the first direction is located within the boss. When the outer shell is deformed, the first insulating member connected to the first wall is also displaced toward the electrode body. The boss of the first insulating member contacts the electrode assembly first, and under the stopping action of the boss, the movement of the second insulating member toward the electrode assembly is blocked, which helps to reduce the risk of the second insulating member crushing the electrode assembly, thereby reducing the risk of internal short circuit in the battery cell, and helps to improve the reliability of the battery cell.

[0007] According to some embodiments of the present application, the first insulating member includes at least two bosses, and the at least two bosses are located on both sides of the second insulating member along the first direction.

[0008] In the above scheme, when the first wall is deformed, the bosses on both sides of the second insulating member along the first direction respectively abut against the electrode body, and provide a stopping effect for the second insulating member twice along the first direction, which is beneficial to further reduce the extrusion of the second insulating member on the electrode body, and further reduce the risk of the electrode body being damaged by extrusion.

[0009] According to some embodiments of the present application, a second insulating member is provided to cover the welding portion.

[0010] In the above scheme, the surface of the welding part facing away from the electrode terminal is covered by the second insulating member, which is beneficial to improving the covering effect of the second insulating member on the welding slag remaining on the side of the welding part facing the electrode assembly, and further helps to reduce the risk of welding slag falling into the interior of the electrode assembly and damaging the electrode assembly.

[0011] According to some embodiments of the present application, along the thickness direction, the area of ​​the orthographic projection of the second insulating member on the first wall is S1, the area of ​​the orthographic projection of the welding portion on the first wall is S2, and S1 / S2≥1.2.

[0012] In the above solution, by setting S1 / S2≥1.2, the welding portion and the surrounding adjacent areas can be covered by the second insulating member to further reduce the risk of welding slag entering the interior of the electrode assembly and damaging the electrode assembly.

[0013] According to some embodiments of the present application, the current collecting member has a groove, the groove is recessed toward the electrode terminal, the welding portion is disposed on the bottom wall of the groove, and at least a portion of the second insulating member is disposed in the groove.

[0014] In the above scheme, during the welding process of the welding part and the electrode terminal, the welding part and the electrode terminal are better fitted, and the welding process of the welding part and the electrode terminal is smoothly carried out. In addition, during the process of forming the second insulating member by coating the fluid glue, the groove can provide a certain limit for the fluid glue, reducing the risk of the fluid glue flowing to other parts of the current collector and interfering with other structures.

[0015] According to some embodiments of the present application, the second insulating member includes an adhesive layer, and the adhesive layer is disposed on a side of the second insulating member facing the electrode assembly.

[0016] In the above solution, the second insulating member includes an adhesive layer, which facilitates controlling the surface morphology and the size along the thickness direction of the second insulating member facing the electrode assembly, and further helps to reduce the risk of the first insulating member squeezing the electrode assembly.

[0017] According to some embodiments of the present application, the material of the adhesive layer includes at least one of epoxy resin, vinyl acetate resin, polyurethane, acrylic acid and polyvinyl alcohol.

[0018] In the above scheme, epoxy resin, vinyl acetate resin, polyurethane, acrylic acid and polyvinyl alcohol have high corrosion resistance, and epoxy resin, vinyl acetate resin, polyurethane, acrylic acid and polyvinyl alcohol have high structural stability after curing and molding, which is beneficial to improve the structural stability of the second insulating member.

[0019] In the second aspect, the manufacturing method of the battery cell provided in the embodiment of the present application includes: providing a first wall, a current collector, an electrode terminal and a first insulating member, the electrode terminal is arranged on the first wall, the first insulating member is arranged on the side of the first wall facing the electrode body, the first insulating member has a boss protruding away from the first wall, the current collector is arranged on the side of the first insulating member facing away from the first wall, the current collector has a welding part, the welding part is welded to the electrode terminal, the boss is arranged on one side of the welding part along a first direction, and the first direction intersects with the thickness direction of the first wall; fluid glue is coated on the side of the welding part facing away from the electrode terminal; and the fluid glue is subjected to a hot pressing process to form a second insulating member, and the orthographic projection of the second insulating member along the first direction is located within the boss.

[0020] The manufacturing method of the battery cell provided in the embodiment of the present application performs a hot pressing process on the fluid glue to control the size of the second insulating part formed by curing the fluid glue along the thickness direction of the first wall, and to control the surface morphology of the second insulating part on the side facing away from the welding part to make its surface smoother, so that the positive projection of the second insulating part along the first direction is located within the boss. After the battery cell is manufactured, the boss has a certain stopping effect on the movement of the second insulating part toward the electrode assembly, which is beneficial to reduce the risk of the second insulating part crushing the electrode assembly, thereby reducing the risk of internal short circuit in the battery cell, and is beneficial to improving the reliability of the battery cell.

[0021] According to some embodiments of the present application, the step of performing a hot pressing process on the fluid glue includes: performing a hot pressing process on the fluid glue using a hot pressing device, the hot pressing device having a heating surface, the heating surface being used to heat and extrude the fluid glue, wherein the heating surface is arranged to cover the welding portion.

[0022] In the above scheme, by setting up a heating surface to cover the welding part, it is beneficial to improve the uniformity of heating the fluid glue by the heating surface, and provide a more uniform extrusion pressure on the area of ​​the welding part covered by the fluid glue, which is beneficial to improve the covering effect of the second insulating part after solidification on the welding slag of the welding part, and further helps to reduce the risk of welding slag in the welding part of the manufactured battery cell falling into the interior of the electrode assembly and damaging the electrode assembly.

[0023] According to some embodiments of the present application, the current collecting part has a groove, the groove is recessed toward the electrode terminal, the welding part is arranged on the bottom wall of the groove, and the heating surface covers the groove; the step of coating the fluid glue on the side of the welding part facing away from the electrode terminal includes: coating the fluid glue on the side of the welding part in the groove facing away from the electrode terminal.

[0024] In the above scheme, a heating surface covering groove setting is provided, which is beneficial to improving the uniformity of heating and extrusion force of the fluid glue by the heating surface during the hot pressing process of the fluid glue, so as to make the size of the cured second insulating part along the thickness direction uniform, and facilitate the goal of the orthographic projection of the second insulating part along the first direction being located within the boss.

[0025] According to some embodiments of the present application, along a direction perpendicular to the thickness direction of the first wall, a distance d between an edge of the heating surface and an edge of the welding portion satisfies: 2 mm ≤ d ≤ 10 mm.

[0026] In the above scheme, setting 2mm≤d≤10mm is beneficial to improving the covering effect of the heating surface on the welding part, thereby improving the covering effect of the second insulating part on the welding part after curing, and is also beneficial to reducing the energy damage of the hot pressing equipment.

[0027] According to some embodiments of the present application, the hot pressing equipment also includes a positioning surface, and the plane where the heating surface is located is located on the side of the plane where the positioning surface is located facing the first wall. The steps of performing a hot pressing process on the fluid glue include: starting the hot pressing equipment, and the positioning surface moves along the thickness direction toward the first insulating part until the positioning surface is in contact with the boss.

[0028] In the above scheme, the cooperation between the positioning surface and the boss of the hot pressing equipment can provide a certain stopping effect for the movement of the heating surface toward the fluid glue, so as to control the distance that the heating surface moves toward the fluid glue, thereby facilitating the control of the size of the second insulating part along the thickness direction after curing.

[0029] According to some embodiments of the present application, the protruding distance of the boss along the thickness direction is d1, the distance between the plane where the positioning surface is located and the plane where the heating surface is located along the thickness direction is d2, and 0.05≤d2 / d1≤0.3.

[0030] In the above scheme, by setting 0.05≤d2 / d1≤0.3, it is beneficial to achieve the purpose of locating the projection of the second insulating member along the first direction inside the boss, so as to reduce the risk of the second insulating member crushing the electrode body, and it is also beneficial to reduce the risk of the fluid glue flowing to other parts of the current collecting member and interfering with related mechanisms.

[0031] In a third aspect, the battery device provided in the embodiments of the present application includes the battery cell provided in any of the above embodiments, or a battery cell manufactured using the manufacturing method of the battery cell provided in any of the above embodiments.

[0032] The battery device provided in the embodiment of the present application has the same technical effects as the battery cell provided in any of the above embodiments, or the battery cell manufactured by the manufacturing method of the battery cell provided in any of the above embodiments, and thus will not be described in detail here.

[0033] In a fourth aspect, the power-consuming device provided in the embodiments of the present application includes the battery device provided in the above embodiments, and the battery device is used to provide electrical energy.

[0034] The electric device provided in the embodiment of the present application has the same technical effect as the battery device provided in the above embodiment, and thus will not be described in detail here.

[0035] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 A schematic diagram of the structure of a vehicle provided in an embodiment of the present application; Figure 2 A schematic diagram of the structure of a battery device provided in an embodiment of the present application; Figure 3 A schematic diagram of the structure of a battery module in a battery device provided in an embodiment of the present application; Figure 4 A schematic diagram of the explosion structure of a battery cell in a battery device provided in an embodiment of the present application; Figure 5 A front view of a partial structure of a battery cell provided in an embodiment of the present application; Figure 6 A schematic diagram of a partial structure of a battery cell provided in an embodiment of the present application; Figure 7 A flowchart of a method for manufacturing a battery cell provided in an embodiment of the present application; Figure 8 A schematic diagram of the structure of a battery cell during the manufacturing process provided in an embodiment of the present application; Fig. 9 for Figure 8 A partial enlarged view of point A in the middle.

[0038] In the drawings, the figures are not necessarily drawn to scale.

[0039] Description of reference numerals: 1- Vehicle; 10-battery device; 11-box; 111-first sub-box; 112-second sub-box; 1a-motor; 1b-controller; 20-battery module; 30 - battery cell; 31 - shell; 311 - housing; 312 - end cover; 313 - first wall; 32 - electrode assembly; 321 - electrode body; 322 - pole ear; 33 - electrode terminal; 40-current collecting member; 40a-groove; 41-welding portion; 50-first insulating member; 51-boss; 60- second insulating member; 61- fluid glue; 2-hot pressing equipment; 2a-heating surface; 2b-positioning surface; X-first direction; Y-thickness direction. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0041] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0042] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0043] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", 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 a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0045] The term "multiple" as used in the present application refers to more than two (including two). Similarly, the term "multiple groups" refers to more than two groups (including two groups), and the term "multiple sheets" refers to more than two sheets (including two sheets).

[0046] The battery apparatus mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple battery cells, which are connected in series, in parallel or in mixed connection through a busbar component.

[0047] In some embodiments, a battery cell assembly is generally formed by arranging a plurality of battery cells; as an example, a battery cell assembly may be a battery module, and a battery module is formed by arranging and fixing a plurality of battery cells to form an independent module. As an example, a battery module may be formed by bundling a plurality of battery cells by a cable tie.

[0048] In some embodiments, the battery device may be a battery pack, which includes a case and one or more battery cell assemblies, wherein the battery cell assemblies are accommodated in the case.

[0049] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0050] As an example, the battery cell assembly may also be housed in the case by directly fixing a plurality of battery cells to the case.

[0051] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0052] In some embodiments, the battery device may be an energy storage device, which includes an energy storage container, an energy storage cabinet, and the like.

[0053] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0054] The battery cells may be, but are not limited to, lithium ion batteries, sodium ion batteries, sodium lithium ion batteries, lithium metal batteries, sodium metal batteries, lithium sulfur batteries, magnesium ion batteries, nickel hydrogen batteries, nickel cadmium batteries, lead storage batteries, etc.

[0055] A battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of a battery cell, active ions (such as lithium ions) are inserted and removed back and forth between the positive electrode and the negative electrode. The separator is set between the positive electrode and the negative electrode to prevent the positive and negative electrodes from short-circuiting, while allowing active ions to pass through.

[0056] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0057] 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 disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0058] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, stainless steel, stainless steel, copper, aluminum, carbon electrode, carbon, nickel or titanium with surface silver plating may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0059] 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 conventional materials that can be used as positive electrode active materials for battery cells may also be used.

[0060] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0061] As an example, the negative electrode current collector may be a metal foil or a composite current collector. For example, the metal foil may be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, copper, aluminum, carbon electrode, carbon, nickel or titanium.

[0062] In some embodiments, the negative electrode current collector has two surfaces opposite to each other in its thickness direction, and the negative electrode active material is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.

[0063] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells 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 battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0064] In some embodiments, the diaphragm is an isolation membrane. The present application has no particular limitation on the type of isolation membrane, and any known isolation membrane with a porous structure having good chemical stability and mechanical stability can be selected.

[0065] As an example, the main 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 special restrictions. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without special restrictions. The separator can be a separate component located between the positive and negative electrodes, or it can be attached to the surface of the positive and negative electrodes.

[0066] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transmit ions and isolate the positive and negative electrodes.

[0067] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into the wound structure.

[0068] In some embodiments, the electrode assembly is a laminate structure.

[0069] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film.

[0070] In some embodiments, the housing includes an end cap and a shell, the shell is provided with an opening, and the end cap closes the opening to form a closed space for accommodating substances such as the electrode assembly and the electrolyte. The shell may be provided with one or more openings. One or more end caps may also be provided.

[0071] In some embodiments, at least one electrode terminal is disposed on the housing, and the electrode terminal is electrically connected to the electrode tab of the electrode assembly. The electrode terminal may be directly connected to the electrode tab, or may be indirectly connected to the electrode tab through a current collector. The electrode terminal may be disposed on an end cap, or may be disposed on the housing.

[0072] In some embodiments, an explosion-proof valve is provided on the housing, and the explosion-proof valve is used to release the internal pressure of the battery cell.

[0073] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, a polygonal prismatic battery, such as a hexagonal prismatic battery, etc. There is no particular limitation in the embodiments of the present application.

[0074] During the manufacturing process of battery cells, the current collector electrically connects the electrode terminal and the tab. The connection between the current collector and the electrode terminal is usually welded, and the current collector and the electrode terminal are usually welded on the side of the current collector facing away from the electrode terminal. A portion of the welding slag generated during the welding process between the current collector and the electrode terminal will remain on the side of the current collector facing the electrode assembly. In order to reduce the risk of welding slag falling into the interior of the electrode assembly and damaging the electrode assembly, a glue layer is usually applied to the side of the welding portion between the current collector and the electrode terminal facing the electrode assembly after welding is completed to cover the welding slag.

[0075] However, the problem of electrode assembly damage still exists in related products. To this end, the inventors conducted in-depth research and a series of experiments. The results showed that in the process of coating the adhesive layer on the side of the current collector facing the electrode assembly, the thickness of the adhesive layer may not be well controlled, and the adhesive layer after solidification usually has a convex peak. During the use of the battery cell, the convex peak moves toward the electrode assembly as the shell of the battery cell deforms. The convex peak has the risk of crushing the electrode assembly, and then causing the risk of internal short circuit in the battery cell, which seriously affects the reliability of the battery cell.

[0076] In view of this, the battery cell provided in the embodiment of the present application includes a shell, an electrode terminal, an electrode assembly, a first insulating member, a current collector and a second insulating member. The shell has a first wall, the electrode terminal is arranged on the first wall, and the electrode assembly includes an electrode body and a pole ear, and the pole ear is led out from the end of the electrode body along the thickness direction Y of the first wall. The first insulating member is arranged on the side of the first wall facing the electrode body, and the first insulating member has a boss protruding toward the electrode body. The current collector is arranged on the side of the first insulating member facing the electrode body, the current collector electrically connects the pole ear and the electrode terminal, the current collector has a welding portion, the welding portion is welded to the electrode terminal, the boss is located on one side of the welding portion along the first direction, and the first direction intersects with the thickness direction. The second insulating member is arranged on the side of the welding portion facing the electrode body, and the orthographic projection of the second insulating member along the first direction is located within the boss.

[0077] The battery cell provided in the embodiment of the present application is configured such that the orthographic projection of the second insulating member along the first direction is located within the boss. When the outer shell is deformed, the first insulating member connected to the first wall also moves toward the electrode body. The boss of the first insulating member contacts the electrode assembly first, and under the stopping action of the boss, the second insulating member no longer moves toward the electrode assembly, which helps to reduce the risk of the second insulating member crushing the electrode assembly, thereby reducing the risk of internal short circuit in the battery cell, and helps to improve the reliability of the battery cell.

[0078] The technical solutions described in the embodiments of the present application are applicable to a battery cell, a battery device including the battery cell, an electric device using the battery device, and a method for manufacturing the battery cell.

[0079] The battery device disclosed in the embodiment of the present application can be used in, but not limited to, electrical devices such as vehicles, ships, or aircraft. The battery device disclosed in the present application can be used to form a power supply system of the electrical device.

[0080] The embodiment of the present application provides an electric device using a battery device as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, an electric tool, an electric bicycle, an electric motorcycle, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, etc.

[0081] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device in an embodiment of the present application.

[0082] Please refer to Figure 1 , Figure 1A schematic diagram of the structure of a vehicle 1 provided in an embodiment of the present application. The vehicle 1 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, etc. A battery device 10 is provided inside the vehicle 1, and the battery device 10 may be provided at the bottom, head or tail of the vehicle 1. The battery device 10 may be used to power the vehicle 1, for example, the battery device 10 may be used as an operating power source for the vehicle 1, for the circuit system of the vehicle 1, for example, for the working power requirements during the startup, navigation and operation of the vehicle 1.

[0083] The vehicle 1 may further include a controller 1b and a motor 1a, wherein the controller 1b is used to control the battery device 10 to supply power to the motor 1a, for example, to meet the power requirements of starting, navigating, and driving the vehicle 1.

[0084] In some embodiments of the present application, the battery device 10 can not only serve as an operating power source for the vehicle 1 , but also serve as a driving power source for the vehicle 1 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1 .

[0085] Please refer to Figure 2 and Figure 3 , Figure 2 This is a schematic diagram of the structure of the battery device 10 provided in an embodiment of the present application. Figure 3 Schematic diagram of the structure of the battery module 20 in the battery device 10 provided in an embodiment of the present application. The battery device 10 includes a box 11 and a battery cell 30, and the battery cell 30 is accommodated in the box 11. Among them, the box 11 is used to provide a storage space for the battery cell 30, and the box 11 can adopt a variety of structures. In some embodiments, the box 11 may include a first sub-box 111 and a second sub-box 112, the first sub-box 111 and the second sub-box 112 cover each other, and the first sub-box 111 and the second sub-box 112 jointly define a storage space for accommodating the battery cell 30. The second sub-box 112 may be a hollow structure with one end open, and the first sub-box 111 may be a plate-like structure, and the first sub-box 111 covers the open side of the second sub-box 112, so that the first sub-box 111 and the second sub-box 112 jointly define a storage space; the first sub-box 111 and the second sub-box 112 may also be hollow structures both with one side open, and the open side of the first sub-box 111 covers the open side of the second sub-box 112.

[0086] In the battery device 10, there may be multiple battery cells 30, and the multiple battery cells 30 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 30 are both connected in series and in parallel. The multiple battery cells 30 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 30 is accommodated in the box 11; of course, the battery device 10 may also be a battery module 20 in the form of multiple battery cells 30 connected in series, in parallel, or in a mixed connection, and then the multiple battery modules 20 are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 11. The battery device 10 may also include other structures, for example, the battery device 10 may also include a busbar component for realizing electrical connection between the multiple battery cells 30.

[0087] The battery cell 30 may be a secondary battery or a primary battery; the battery cell 30 may also be a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited thereto.

[0088] Please refer to Figure 4 , Figure 4 Schematic diagram of the exploded structure of the battery cell 30 in the battery device 10 provided in the embodiment of the present application. Figure 4 As shown, the battery cell 30 includes a housing 31, an electrode assembly 32 and an electrode terminal 33. The housing 31 includes a shell 311 and an end cap 312. The shell 311 has an opening, and the end cap 312 closes the opening to isolate the internal environment of the battery cell 30 from the external environment.

[0089] The shell 311 is a component used to cooperate with the end cap 312 to form the internal environment of the battery cell 30, wherein the formed internal environment can be used to accommodate the electrode assembly 32, the electrolyte and other components. The shell 311 and the end cap 312 can be independent components. The shell 311 can be of various shapes and sizes. Specifically, the shape of the shell 311 can be determined according to the specific shape and size of the electrode assembly 32. The material of the shell 311 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0090] The end cap 312 refers to a component that covers the opening of the shell 311 to isolate the internal environment of the battery cell 30 from the external environment. Without limitation, the shape of the end cap 312 can be adapted to the shape of the shell 311 to match the shell 311. Optionally, the end cap 312 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 312 is not easily deformed when squeezed and collided, so that the battery cell 30 can have a higher structural strength and reliability can also be improved. Functional components such as electrode terminals 33 can be provided on the end cap 312. The electrode terminal 33 can be used to electrically connect to the electrode assembly 32 for outputting or inputting electrical energy of the battery cell 30. The material of the end cap 312 can also be a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose any special restrictions on this. In some embodiments, an insulating structure may be provided inside the end cap 312, and the insulating structure may be used to isolate the electrical connection components in the housing 311 from the end cap 312 to reduce the risk of short circuit. For example, the insulating structure may be plastic, rubber, or the like.

[0091] The electrode assembly 32 is a component in the battery cell 30 where an electrochemical reaction occurs. One or more electrode assemblies 32 may be included in the housing 311. The electrode assembly 32 is mainly formed by winding or stacking the positive electrode sheet and the negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet, and the separator is used to separate the positive electrode sheet and the negative electrode sheet to avoid short circuits between the positive electrode sheet and the negative electrode sheet. The parts of the positive electrode sheet and the negative electrode sheet with active materials constitute the electrode body 321 of the electrode assembly 32, and the parts of the positive electrode sheet and the negative electrode sheet without active materials each constitute the tabs 322. The positive tab and the negative tab may be located together at one end of the electrode body 321 or at both ends of the electrode body 321, respectively. During the charge and discharge process of the battery cell 30, the positive active material and the negative active material react with the electrolyte, and the tabs 322 are connected to the electrode terminals 33 to form a current loop.

[0092] First, as Figure 4 , Figure 5 , Figure 6 and Figure 8As shown, the battery cell 30 provided in the embodiment of the present application includes a housing 31, an electrode terminal 33, an electrode assembly 32, a first insulating member 50, a current collector 40 and a second insulating member 60. The housing 31 has a first wall 313, the electrode terminal 33 is arranged on the first wall 313, and the electrode assembly 32 includes an electrode body 321 and a pole ear 322, and the pole ear 322 is led out from the end of the electrode body 321 along the thickness direction Y of the first wall 313. The first insulating member 50 is arranged on the side of the first wall 313 facing the electrode body 321, and the first insulating member 50 has a boss 51 protruding toward the electrode body 321. The current collector 40 is arranged on the side of the first insulating member 50 facing the electrode body 321, and the current collector 40 electrically connects the pole ear 322 and the electrode terminal 33. The current collector 40 has a welding portion 41, and the welding portion 41 is welded to the electrode terminal 33. The boss 51 is located on one side of the welding portion 41 along the first direction X, and the first direction X intersects with the thickness direction Y. The second insulating member 60 is disposed on a side of the welding portion 41 facing the electrode body 321 , and an orthographic projection of the second insulating member 60 along the first direction X is located within the boss 51 .

[0093] The shell 31 has a first wall 313. Optionally, the first wall 313 may be a part of the shell 311, or the first wall 313 may be at least a part of the end cover 312. Of course, both the shell 311 and the end cover 312 may have the first wall 313. The specific setting may be made according to actual needs.

[0094] The electrode terminal 33 may be connected to the first wall 313 by riveting, injection molding, etc., and insulated from the first wall 313 . In order to achieve electrical connection between the electrode terminal 33 and the current collector 40 , the electrode terminal 33 may be passed through the first wall 313 .

[0095] The electrode assembly 32 includes an electrode body 321 and a pole ear 322, and the pole ear 322 is led out from the end of the electrode body 321 along the thickness direction Y of the first wall 313. Optionally, the pole ear 322 can be led out from one end of the first wall 313 along the thickness direction Y, or the pole ear 322 can be led out from both ends of the electrode body 321 along the thickness direction Y.

[0096] The first insulating member 50 is disposed on the side of the first wall 313 facing the electrode body 321, and the first insulating member 50 can provide a certain insulation effect for the first wall 313 and the electrode assembly 32. The first insulating member 50 has a boss 51 protruding toward the electrode body 321, and the boss 51 can be disposed on both sides of the first insulating member 50 and abut against the electrode body 321 to provide a certain limit effect on the electrode assembly 32, thereby reducing the risk of the electrode assembly 32 shaking in the housing 31.

[0097] Optionally, the first insulating member 50 may have one, two, three or more bosses 51 .

[0098] The current collector 40 is electrically connected to the tab 322 and the electrode terminal 33, and the current collector 40 can be electrically connected to the tab 322 and the electrode terminal 33 respectively by welding. The welding portion 41 of the current collector 40 is electrically connected to the electrode terminal 33, and the current collector 40 can be electrically connected to the tab 322 through other parts other than the welding portion 41.

[0099] The welding portion 41 is welded to the electrode terminal 33, and laser welding can be used to weld the welding portion 41 and the electrode terminal 33 on the side of the welding portion 41 of the current collector 40 that is away from the electrode terminal 33. After welding is completed, some welding slag will remain on the side of the welding portion 41 that is away from the electrode terminal 33.

[0100] The first direction X intersects with the thickness direction Y. Optionally, the first direction X may be perpendicular to the thickness direction Y. The boss 51 is located on one side of the welding portion 41 along the first direction X. When the first insulating member 50 includes a plurality of bosses 51, different bosses 51 may be located on both sides of the welding portion 41 along the first direction X, respectively.

[0101] The second insulating member 60 is disposed on the side of the welding portion 41 facing away from the electrode terminal 33 , and the second insulating member 60 can provide a certain degree of protection for the welding slag on the side of the welding portion 41 facing away from the electrode terminal 33 , so as to reduce the risk of the welding slag falling into the interior of the electrode assembly 32 and causing certain damage to the electrode assembly 32 .

[0102] Optionally, the second insulating member 60 may be formed by solidifying a fluid colloid on the side of the welding portion 41 facing away from the electrode terminal 33 , and the fluid colloid is solidified to form the second insulating member 60 .

[0103] The orthographic projection of the second insulating member 60 along the first direction X is located within the boss 51, and the end surface of the second insulating member 60 along the thickness direction Y facing the electrode assembly 32 may be flush with the end surface of the boss 51 along the thickness direction Y facing the electrode assembly 32, or the plane where the end surface of the second insulating member 60 along the thickness direction Y facing the electrode assembly 32 is located is located on the side of the plane where the end surface of the boss 51 along the thickness direction Y facing the electrode assembly 32 is located facing the first wall 313. In other words, along the thickness direction Y, the second insulating member 60 does not exceed the end of the boss 51 facing the electrode assembly 32.

[0104] In order to make the orthographic projection of the second insulating member 60 along the first direction X be located within the boss 51, the size of the second insulating member 60 along the thickness direction Y can be controlled. Exemplarily, the second insulating member 60 can be a machined part, and the size and surface roughness of the second insulating member 60 along the thickness direction Y are controlled. Alternatively, the second insulating member 60 can be formed by curing the fluid glue 61. During the molding process, the fluid glue 61 can be hot-pressed by a hot-pressing process to reduce the size of the peak of the surface of the formed second insulating member 60 facing the electrode assembly 32, and the size of the second insulating member 60 along the thickness direction Y can be controlled during the hot-pressing process.

[0105] It can be understood that as the shell 31 is deformed, the first insulating member 50 is displaced toward the electrode assembly 32 along with the first wall 313, the boss 51 contacts and abuts against the electrode body 321, and the first wall 313 stops displacing under the stopping action of the boss 51. Since the second insulating member 60 does not exceed the boss 51 along the thickness direction Y, the boss 51 provides a certain stopping effect on the movement of the second insulating member 60 toward the electrode body 321, which helps to reduce the risk of the second insulating member 60 causing a certain amount of extrusion on the electrode body 321.

[0106] The battery cell 30 provided in the embodiment of the present application is configured such that the orthographic projection of the second insulating member 60 along the first direction X is located within the boss 51. When the outer shell 31 is deformed, the first insulating member 50 connected to the first wall 313 is also displaced toward the electrode body 321. The boss 51 of the first insulating member 50 is first in contact with the electrode assembly 32, and under the stopping action of the boss 51, the movement of the second insulating member 60 toward the electrode assembly 32 is blocked, which is beneficial to reduce the risk of the second insulating member 60 crushing the electrode assembly 32, thereby reducing the risk of internal short circuit in the battery cell 30, and is beneficial to improving the reliability of the battery cell 30.

[0107] In some embodiments, Figure 5 As shown, the first insulating member 50 includes at least two bosses 51 , and the at least two bosses 51 are located on both sides of the second insulating member 60 along the first direction X.

[0108] At least two bosses 51 are provided and are respectively located on both sides of the second insulating member 60 along the first direction X. Optionally, the two bosses 51 can be respectively located at both ends of the first insulating member 50 along the first direction X. In this way, when the first wall 313 is deformed, the bosses 51 on both sides of the second insulating member 60 along the first direction X respectively abut against the electrode body 321, and provide a stopping effect for the second insulating member 60 twice along the first direction X, which is beneficial to further reduce the extrusion of the second insulating member 60 on the electrode body 321, and further reduce the risk of the electrode body 321 being damaged by extrusion.

[0109] In some embodiments, the second insulating member 60 is disposed to cover the welding portion 41 .

[0110] The second insulating member 60 is arranged to cover the welding portion 41, so that the surface of the welding portion 41 facing away from the electrode terminal 33 is covered by the second insulating member 60, which is beneficial to improving the covering effect of the second insulating member 60 on the welding slag remaining on the side of the welding portion 41 facing the electrode assembly 32, and further helps to reduce the risk of the welding slag falling into the interior of the electrode assembly 32 and damaging the electrode assembly 32.

[0111] In some embodiments, along the thickness direction Y, the area of ​​the orthographic projection of the second insulating member 60 on the first wall 313 is S1, the area of ​​the orthographic projection of the welding portion 41 on the first wall 313 is S2, and S1 / S2≥1.2.

[0112] Optionally, S1 / S2 can be 1.2, 1.3, 1.4 or 1.5, etc.

[0113] It is understandable that after the welding of the welding part 41 and the electrode terminal 33 is completed, the welding slag may splash into a certain area around the welding part 41. By setting S1 / S2≥1.2, the welding part 41 and the adjacent area therearound can be covered by the second insulating member 60 to further reduce the risk of the welding slag entering the interior of the electrode assembly 32 and damaging the electrode assembly 32.

[0114] In some embodiments, Figure 6 As shown, the current collector 40 has a groove 40a, which is recessed toward the electrode terminal 33, the welding portion 41 is disposed on the bottom wall of the groove 40a, and at least a portion of the second insulating member 60 is disposed in the groove 40a.

[0115] The current collector 40 has a groove 40a, which can be formed by a stamping process. The welding portion 41 is arranged on the bottom wall of the groove 40a, and the welding portion 41 is protruded toward the electrode terminal 33 relative to other parts of the current collector 40. In this way, during the welding process of the welding portion 41 and the electrode terminal 33, the welding portion 41 and the electrode terminal 33 can be better fitted, which facilitates the smooth progress of the welding process of the welding portion 41 and the electrode terminal 33.

[0116] At least part of the second insulating member 60 is disposed in the groove 40a, and the groove 40a can provide a certain limiting effect on the second insulating member 60, thereby reducing the risk of the second insulating member 60 being separated from the welding portion 41. In the process of forming the second insulating member 60 by coating the fluid glue 61, the groove 40a can provide a certain limiting effect for the fluid glue 61, thereby reducing the risk of the fluid glue 61 flowing to other parts of the current collecting member 40 and interfering with other structures.

[0117] In some embodiments, the second insulating member 60 includes an adhesive layer, and the adhesive layer is disposed on a side of the second insulating member 60 facing the electrode assembly 32 .

[0118] The second insulating member 60 includes an adhesive layer. Optionally, the second insulating member 60 may include only the adhesive layer, or may include other structures other than the adhesive layer.

[0119] The adhesive layer is disposed on the side of the second insulating member 60 facing the electrode assembly 32 . When the first wall 313 is deformed, the adhesive layer tends to contact and abut against the electrode assembly 32 .

[0120] The adhesive layer can be formed after the fluid glue 61 coated on the welding part 41 is solidified. During the curing process of the adhesive layer, the surface morphology and the size of the adhesive part along the thickness direction Y can be controlled by hot pressing the fluid glue 61 to further reduce the extrusion of the adhesive layer on the electrode assembly 32.

[0121] Therefore, the second insulating member 60 is provided with an adhesive layer, which facilitates controlling the surface morphology of the second insulating member 60 on the side facing the electrode assembly 32 and the size along the thickness direction Y, and further helps to reduce the risk of the first insulating member 50 squeezing the electrode assembly 32.

[0122] In some embodiments, the material of the adhesive layer includes at least one of epoxy resin, vinyl acetate resin, polyurethane, acrylic acid, and polyvinyl alcohol.

[0123] Epoxy resin, vinyl acetate resin, polyurethane, acrylic acid and polyvinyl alcohol have high corrosion resistance and high structural stability after curing, which is beneficial to improve the structural stability of the second insulating member 60.

[0124] Second, as Figure 7 and Figure 8 As shown, the manufacturing method of the battery cell 30 provided in the embodiment of the present application includes: S10. Provide a first wall 313, a current collector 40, an electrode terminal 33 and a first insulating member 50, wherein the electrode terminal 33 is arranged on the first wall 313, the first insulating member 50 is arranged on a side of the first wall 313 facing the electrode body 321, the first insulating member 50 has a boss 51 protruding away from the first wall 313, the current collector 40 is arranged on a side of the first insulating member 50 facing away from the first wall 313, the current collector 40 has a welding portion 41, the welding portion 41 is welded to the electrode terminal 33, the boss 51 is arranged on one side of the welding portion 41 along a first direction X, and the first direction X intersects with a thickness direction Y of the first wall 313.

[0125] S20 , applying fluid glue 61 on the side of the welding portion 41 facing away from the electrode terminal 33 .

[0126] S30 , performing a hot pressing process on the fluid glue 61 to form a second insulating member 60 , wherein the orthographic projection of the second insulating member 60 along the first direction X is located within the boss 51 .

[0127] The first wall 313, the current collector 40, the electrode terminal 33 and the first insulating member 50 provided in step S10 are assembled components, wherein the welding portion 41 of the current collector 40 and the electrode terminal 33 have been welded together, and welding slag will inevitably remain on the side of the welding portion 41 facing away from the electrode terminal 33.

[0128] In step S20, fluid glue 61 is coated on the side of the welding portion 41 facing away from the electrode terminal 33. The fluid glue 61 can cover the side of the welding portion 41 facing away from the electrode terminal 33 and extend beyond the edge of the welding portion 41 to improve the curing effect of the fluid glue 61 on the welding portion 41.

[0129] In step S30, the fluid glue 61 is subjected to a hot pressing process, that is, a hot pressing device 2 is used to pressurize and heat the fluid glue 61 that has been coated on the welding portion 41 to control the thickness and uniformity of the coated fluid glue 61, so that the fluid glue 61 is more evenly distributed on the welding portion 41, and the surface of the molded second insulating member 60 on the side facing away from the welding portion 41 is smoother, the height of the peak on the surface of the second insulating member 60 is reduced, and the size of the second insulating member 60 along the thickness direction Y is controlled, so that the positive projection of the second insulating member 60 along the first direction X is located within the boss 51.

[0130] It can be understood that after step S30, the battery cell 30 can be assembled. In the assembled battery cell 30, the current collector 40 electrically connects the electrode tab 322 and the electrode terminal 33 of the electrode assembly 32, and the second insulating member 60 is located on the side of the welding portion 41 facing the electrode body 321 of the electrode assembly 32.

[0131] If the orthographic projection of the second insulating member 60 along the first direction X is located within the boss 51, the second insulating member 60 is not set beyond the boss 51. In other words, the surface of the second insulating member 60 facing away from the welding portion 41 is flush with the surface of the boss 51 facing away from the first wall 313, or the plane where the surface of the second insulating member 60 facing away from the welding portion 41 is located is located on the side of the boss 51 facing away from the first wall 313.

[0132] The manufacturing method of the battery cell 30 provided in the embodiment of the present application performs a hot pressing process on the fluid glue 61 to control the size of the second insulating member 60 formed by curing the fluid glue 61 along the thickness direction Y of the first wall 313, and to control the surface morphology of the second insulating member 60 on the side facing away from the welding portion 41, so that its surface is smoother, so that the positive projection of the second insulating member 60 along the first direction X is located within the boss 51. After the battery cell 30 is manufactured, the boss 51 has a certain stopping effect on the movement of the second insulating member 60 toward the electrode assembly 32, which is beneficial to reduce the risk of the second insulating member 60 crushing the electrode assembly 32, thereby reducing the risk of internal short circuit of the battery cell 30, and is beneficial to improving the reliability of the battery cell 30.

[0133] It can be understood that the method for manufacturing the battery cell 30 provided in the embodiment of the present application can be used to manufacture the battery cell 30 provided in any of the above embodiments.

[0134] In some embodiments, Figure 7 and Figure 8 As shown, S30, the step of performing a hot pressing process on the fluid glue 61, comprises: The hot pressing device 2 is used to perform a hot pressing process on the fluid glue 61 . The hot pressing device 2 has a heating surface 2 a . The heating surface 2 a is used to heat and extrude the fluid glue 61 . The heating surface 2 a is arranged to cover the welding portion 41 .

[0135] Specifically, in the process of performing the hot pressing process on the fluid glue 61 using the hot pressing device 2 , the hot pressing device 2 heats and extrude the fluid glue 61 by attaching the heating surface 2 a to the fluid glue 61 .

[0136] The fluid glue 61 has a certain fluidity. During the process of the hot pressing equipment 2 extruding the fluid glue 61, the flow of the fluid glue 61 can improve the uniformity of the size of the second insulating part 60 along the thickness direction Y after curing and make the surface of the second insulating part 60 that is in contact with the heating surface 2a have a relatively flat surface morphology.

[0137] Setting the heating surface 2a to cover the welding portion 41 is beneficial to improving the uniformity of heating the fluid glue 61 by the heating surface 2a, and providing a more uniform extrusion pressure to the area where the fluid glue 61 covers the welding portion 41, which is beneficial to improving the covering effect of the second insulating member 60 on the welding slag of the welding portion 41 after solidification, and further helps to reduce the risk of the welding slag of the welding portion 41 in the manufactured battery cell 30 falling into the interior of the electrode assembly 32 and damaging the electrode assembly 32.

[0138] In some embodiments, Figure 6 , Figure 7 and Figure 8As shown, the current collector 40 has a groove 40a, the groove 40a is recessed toward the electrode terminal 33, the welding portion 41 is arranged on the bottom wall of the groove 40a, and the heating surface 2a covers the groove 40a; S20, the step of coating the fluid glue 61 on the side of the welding portion 41 facing away from the electrode terminal 33, comprising: The fluid glue 61 is applied to the side of the welding portion 41 in the groove 40 a facing away from the electrode terminal 33 .

[0139] The current collecting part 40 has a groove 40a, and the groove 40a can be formed by a stamping process. The welding part 41 is located on the bottom wall of the groove 40a, and the welding part 41 is protruded toward the direction of the electrode terminal 33. During the welding process of the welding part 41 and the electrode terminal 33, the welding part 41 is facilitated to fit with the electrode terminal 33, which is beneficial to improve the smoothness of the welding process between the two.

[0140] And since the welding portion 41 is arranged on the bottom wall of the groove 40a, during the step S20, the fluid glue 61 can be added into the groove 40a, and the groove 40a can provide a certain limiting effect for the fluid glue 61, thereby reducing the risk of the fluid glue 61 flowing to other parts of the current collecting part 40 and interfering with related structures.

[0141] The heating surface 2a is arranged to cover the groove 40a. During the hot pressing process of the fluid glue 61, it is beneficial to improve the uniformity of heating and extrusion force of the heating surface 2a on the fluid glue 61, so that the size of the cured second insulating member 60 along the thickness direction Y has a high uniformity, and it is easy to achieve the goal of the orthographic projection of the second insulating member 60 along the first direction X being located within the boss 51.

[0142] In some embodiments, along a direction perpendicular to the thickness direction Y of the first wall 313 , a distance d between an edge of the heating surface 2 a and an edge of the welding portion 41 satisfies: 2 mm≤d≤10 mm.

[0143] Optionally, d can be 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm or 10mm, etc.

[0144] By setting 2mm≤d, the design value of the heating surface 2a, while covering the welding portion 41, also exceeds the edge of the welding portion 41 by a certain distance, so that when the installation position and size of the heating surface 2a are within the allowable error range, the heating surface 2a can still cover the welding portion 41, which is beneficial to improving the covering effect of the heating surface 2a on the welding portion 41. By setting d≤10mm, while improving the covering effect of the heating surface 2a on the welding portion 41, it is also beneficial to reduce the area of ​​the heating surface 2a and reduce energy loss.

[0145] Therefore, after systematic analysis and long-term practice, the inventors found that setting 2mm≤d≤10mm is beneficial to improving the coverage effect of the heating surface 2a on the welding part 41, thereby improving the coverage effect of the second insulating part 60 on the welding part 41 after curing, and it is also beneficial to reduce the energy damage of the hot pressing equipment 2.

[0146] In some embodiments, Figure 7 , Figure 8 and Fig. 9 As shown, the hot pressing device 2 further includes a positioning surface 2b, and the plane where the heating surface 2a is located is located on the side of the plane where the positioning surface 2b is located facing the first wall 313. The steps of hot pressing the fluid glue 61 include: The hot pressing device 2 is started, and the positioning surface 2 b moves toward the first insulating member 50 along the thickness direction Y until the positioning surface 2 b is in contact with the boss 51 .

[0147] Start the hot pressing device 2, and the heating surface 2a of the hot pressing device 2 gradually moves toward the fluid glue 61 until the positioning surface 2b and the boss 51 are in contact with each other. In this way, the cooperation between the positioning surface 2b of the hot pressing device 2 and the boss 51 can provide a certain stopping effect for the movement of the heating surface 2a toward the fluid glue 61, so as to control the distance that the heating surface 2a moves toward the fluid glue 61, thereby facilitating the control of the size of the second insulating member 60 along the thickness direction Y after curing.

[0148] In some embodiments, Figure 7 , Figure 8 and Fig. 9 As shown, the protruding distance of the boss 51 along the thickness direction Y is d1, the distance between the plane where the positioning surface 2b is located and the plane where the heating surface 2a is located along the thickness direction Y is d2, and 0.05≤d2 / d1≤0.3.

[0149] It is understandable that when the positioning surface 2b fits the boss 51 , that is, when the heating surface 2a is in place, d2 may be the distance between the surface of the second insulating member 60 after solidification and the surface of the boss 51 .

[0150] Optionally, d2 / d1 can be 0.05, 0.1, 0.15, 0.2, 0.25 or 0.3, etc.

[0151] It can be understood that, to a certain extent, the larger the value of d2 / d1 is, the easier it is to achieve the purpose of having the projection of the second insulating member 60 along the first direction X after solidification be located inside the boss 51, and the smaller the value of d2 / d1 is to a certain extent, the larger the space between the hot pressing surface and the welding part 41 is during the process of hot pressing the fluid glue 61 on the heating surface 2a, and the more conducive it is to reduce the risk of the fluid glue 61 flowing to other parts of the current collecting member 40 under the squeezing of the heating surface 2a and interfering with related mechanisms.

[0152] Therefore, after systematic analysis and long-term practice, the inventors found that by setting 0.05≤d2 / d1≤0.3, it is beneficial to achieve the purpose of locating the projection of the second insulating member 60 along the first direction X inside the boss 51, so as to reduce the risk of the second insulating member 60 crushing the electrode body 321, and it is also beneficial to reduce the risk of the fluid glue 61 interfering with related mechanisms when flowing to other parts of the current collecting member 40.

[0153] In a third aspect, the battery device 10 provided in the embodiment of the present application includes the battery cell 30 provided in any of the above embodiments, or the battery cell 30 manufactured by the manufacturing method of the battery cell 30 provided in any of the above embodiments.

[0154] The battery device 10 provided in the embodiment of the present application has the same technical effects as the battery cell 30 provided in any of the above embodiments, or the battery cell 30 manufactured by the manufacturing method of the battery cell 30 provided in any of the above embodiments, and thus will not be described in detail here.

[0155] In a fourth aspect, the electrical device provided in the embodiment of the present application includes the battery device 10 provided in the above embodiment, and the battery device 10 is used to provide electrical energy.

[0156] The electric device provided in the embodiment of the present application has the same technical effect as the battery device 10 provided in the above embodiment, and thus will not be described in detail here.

[0157] In some embodiments, Figure 4 , Figure 5 and Figure 6As shown, the battery cell 30 includes a housing 31, an electrode terminal 33, an electrode assembly 32, a first insulating member 50, a current collector 40, and a second insulating member 60. The housing 31 has a first wall 313. The electrode terminal 33 is disposed on the first wall 313. The electrode assembly 32 includes an electrode body 321 and a tab 322. The tab 322 is led out from the end of the electrode body 321 along the thickness direction Y of the first wall 313. The first insulating member 50 is disposed on one side of the first wall 313 facing the electrode body 321. The first insulating member 50 has at least two bosses 51 protruding toward the electrode body 321. The at least two bosses 51 are located on both sides of the second insulating member 60 along the first direction X. The current collector 40 is arranged on the side of the first insulating member 50 facing the electrode body 321. The current collector 40 electrically connects the electrode tab 322 and the electrode terminal 33. The current collector 40 has a welding portion 41, which is welded to the electrode terminal 33. The boss 51 is located on the side of the welding portion 41 along the first direction X, and the first direction X intersects with the thickness direction Y. The second insulating member 60 is arranged on the side of the welding portion 41 facing the electrode body 321 and covers the welding portion 41. The orthographic projection of the second insulating member 60 along the first direction X is located within the boss 51. Along the thickness direction Y, the orthographic projection area of ​​the second insulating member 60 on the first wall 313 is S1, and the orthographic projection area of ​​the welding portion 41 on the first wall 313 is S2, and S1 / S2≥1.2. The current collector 40 has a groove 40a, which is recessed toward the electrode terminal 33. The welding portion 41 is arranged on the bottom wall of the groove 40a, and at least part of the second insulating member 60 is arranged in the groove 40a. The second insulating member 60 includes an adhesive layer, which is disposed on a side of the second insulating member 60 facing the electrode assembly 32. The material of the adhesive layer includes at least one of epoxy resin, vinyl acetate resin, polyurethane, acrylic acid and polyvinyl alcohol.

[0158] The battery cell 30 provided in the embodiment of the present application is configured such that the orthographic projection of the second insulating member 60 along the first direction X is located within the boss 51. When the outer shell 31 is deformed, the first insulating member 50 connected to the first wall 313 is also displaced toward the electrode body 321. The boss 51 of the first insulating member 50 is first in contact with the electrode assembly 32, and under the stopping action of the boss 51, the movement of the second insulating member 60 toward the electrode assembly 32 is blocked, which is beneficial to reduce the risk of the second insulating member 60 crushing the electrode assembly 32, thereby reducing the risk of internal short circuit in the battery cell 30, and is beneficial to improving the reliability of the battery cell 30.

[0159] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: a housing having a first wall; an electrode terminal, disposed on the first wall; An electrode assembly, comprising an electrode body and a tab, wherein the tab is led out from an end of the electrode body along the thickness direction of the first wall; A first insulating member, disposed on a side of the first wall facing the electrode body, the first insulating member having a boss protruding toward the electrode body; a current collector, disposed on a side of the first insulating member facing the electrode body, the current collector electrically connecting the electrode tab and the electrode terminal, the current collector having a welding portion, the welding portion being welded to the electrode terminal, the boss being located on one side of the welding portion along a first direction, the first direction intersecting the thickness direction; The second insulating member is arranged on a side of the welding portion facing the electrode body, and the orthographic projection of the second insulating member along the first direction is located within the boss.

2. The battery cell according to claim 1, characterized in that: The first insulating member includes at least two bosses, and the at least two bosses are located on both sides of the second insulating member along the first direction.

3. The battery cell according to claim 1, characterized in that: The second insulating member is disposed to cover the welding portion.

4. The battery cell according to claim 3, characterized in that: Along the thickness direction, an area of ​​an orthographic projection of the second insulating member on the first wall is S1, an area of ​​an orthographic projection of the welding portion on the first wall is S2, and S1 / S2≥1.

2.

5. The battery cell according to claim 1, characterized in that: The current collecting member has a groove, the groove is recessed toward the electrode terminal, the welding portion is arranged on a bottom wall of the groove, and at least a portion of the second insulating member is arranged in the groove.

6. The battery cell according to claim 1, characterized in that: The second insulating member includes an adhesive layer, and the adhesive layer is arranged on a side of the second insulating member facing the electrode assembly.

7. The battery cell according to claim 6, characterized in that: The material of the adhesive layer includes at least one of epoxy resin, vinyl acetate resin, polyurethane, acrylic acid and polyvinyl alcohol.

8. A method for manufacturing a battery cell, characterized in that: include: A first wall, a current collector, an electrode terminal and a first insulating member are provided, wherein the electrode terminal is provided on the first wall, the first insulating member is provided on one side of the first wall, the first insulating member has a boss protruding away from the first wall, the current collector is provided on one side of the first insulating member away from the first wall, the current collector has a welding portion, the welding portion is welded to the electrode terminal, the boss is provided on one side of the welding portion along a first direction, and the first direction intersects with a thickness direction of the first wall; Applying fluid glue on a side of the welding portion facing away from the electrode terminal; The fluid glue is subjected to a hot pressing process to form a second insulating member, wherein the orthographic projection of the second insulating member along the first direction is located within the boss.

9. The method for manufacturing a battery cell according to claim 8, characterized in that: The step of hot pressing the fluid adhesive comprises: A hot pressing process is performed on the fluid adhesive using a hot pressing device, wherein the hot pressing device has a heating surface, and the heating surface is used to heat and extrude the fluid adhesive, wherein the heating surface covers the welding portion.

10. The method for manufacturing a battery cell according to claim 9, characterized in that: The current collector has a groove, the groove is recessed toward the electrode terminal, the welding portion is arranged on the bottom wall of the groove, and the heating surface covers the groove; The step of applying fluid glue on the side of the welding portion facing away from the electrode terminal comprises: Fluid glue is coated on a side of the welding portion in the groove facing away from the electrode terminal.

11. The method for manufacturing a battery cell according to claim 9, characterized in that: Along a direction perpendicular to the thickness direction of the first wall, a distance d between an edge of the heating surface and an edge of the welding portion satisfies: 2 mm ≤ d ≤ 10 mm.

12. The method for manufacturing a battery cell according to claim 9, characterized in that: The hot pressing device further includes a positioning surface, and the plane where the heating surface is located is located on a side of the plane where the positioning surface is located facing the first wall. The step of hot pressing the fluid glue includes: The hot pressing device is started, and the positioning surface moves toward the first insulating member along the thickness direction until the positioning surface is in contact with the boss.

13. The method for manufacturing a battery cell according to claim 12, characterized in that: The protruding distance of the boss along the thickness direction is d1, the distance between the plane where the positioning surface is located and the plane where the heating surface is located along the thickness direction is d2, and 0.05≤d2 / d1≤0.

3.

14. A battery device, characterized in that: A battery cell comprising the battery cell according to any one of claims 1 to 7, or a battery cell manufactured by the battery cell manufacturing method according to any one of claims 8 to 13.

15. An electrical device, characterized in that: Comprising the battery device as claimed in claim 14, the battery device is used to provide electrical energy.

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