Battery cells, battery packs, electrical devices and winding devices

Abstract

A battery cell, a battery device, an electrical device, and a winding device are provided. The battery cell includes an electrode assembly and a first connecting portion. The electrode assembly includes a first electrode, a second electrode, a center pin, and a first separator. The first and second electrodes have opposite polarities. The first electrode, the first separator, and the second electrode are all wound around the outer periphery of the center pin. The first separator includes a first substrate and a first coating, with the first coating disposed on the surface of the first substrate facing the center pin. The first connecting portion is connected to the first substrate and passes through the first coating to connect to the center pin. By providing the first connecting portion, the connection strength between the first separator and the center pin is improved. During the winding process, the first separator is less likely to detach from the center pin, and the first electrode, second electrode, and first separator can be firmly wound around the center pin under tension, reducing the risk of slippage of the first electrode, second electrode, and first separator, thus improving the reliability of the battery cell.

Description

Technical Field

[0001] This application relates to the field of batteries, and more specifically, to a battery cell, a battery device, an electrical device, and a winding device. Background Technology

[0002] Batteries are widely used in the new energy field, such as in electric vehicles and new energy vehicles, which have become a new trend in the automotive industry. The development of battery technology must consider multiple design factors simultaneously, such as energy density, discharge capacity, and charge / discharge rate. Furthermore, battery reliability also needs to be considered. However, current battery reliability is relatively poor. Summary of the Invention

[0003] The purpose of this application is to provide a battery cell, a battery device, an electrical device, and a winding device, which aim to improve the problem of poor battery reliability in related technologies.

[0004] In a first aspect, embodiments of this application provide a battery cell, the battery cell including an electrode assembly and a first connecting portion, the electrode assembly including a first electrode, a second electrode, a center pin and a first separator, the first electrode and the second electrode having opposite polarities, the first electrode, the first separator and the second electrode all being wound around the outer periphery of the center pin, the first separator including a first substrate and a first coating, the first coating being disposed on the surface of the first substrate facing the center pin; the first connecting portion being connected to the first substrate, the first connecting portion passing through the first coating and being connected to the center pin.

[0005] In the above technical solution, by winding the first electrode, the first separator, and the second electrode around the outer periphery of the center pin, the center pin can support the first electrode, the first separator, and the second electrode, thereby reducing the risk of inner ring collapse of the electrode assembly and improving the reliability of the battery cell. By setting a first connecting part and connecting the first connecting part through the first coating to the center pin, the connection between the first substrate and the center pin is achieved, which helps to improve the connection strength between the first separator and the center pin. In this way, during the winding process, the first separator is not easy to detach from the center pin, and the first electrode, the second electrode, and the first separator can be firmly wound around the center pin under tension, which helps to reduce the risk of slippage of the first electrode, the second electrode, and the first separator, and helps to reduce the risk of lithium plating, thus improving the reliability of the battery cell.

[0006] As an optional technical solution in this application embodiment, the first isolation member includes a second coating, the second coating is disposed on the surface of the first substrate away from the center pin, the second coating has a first surface away from the first substrate; the first isolation member is provided with a first recess at a position corresponding to the first connecting portion, the first recess is recessed from the first surface toward the direction close to the center pin, and a portion of the first recess is located in the first substrate.

[0007] In the above technical solution, by setting a first recess and making the first recess recessed from the first surface toward the direction of the center pin, a part of the first recess is located in the first substrate. During manufacturing, energy can be directly applied to the first substrate from the first recess, and is not easily blocked or dispersed by the second coating, so that the first substrate and the center pin are connected to form a first connection part, which is beneficial to improving connection efficiency and connection quality.

[0008] As an optional technical solution in this application embodiment, the depth of the first recess is less than the sum of the thickness of the first substrate and the thickness of the second coating.

[0009] In the above technical solution, by making the depth of the first recess less than the sum of the thickness of the first substrate and the thickness of the second coating, that is, a part of the first recess is located in the second coating and another part of the first recess is located in the first substrate, and the first recess does not penetrate the first substrate, it is beneficial to make the strength of the first substrate higher and reduce the risk of the first substrate tearing during the winding process.

[0010] As an optional technical solution in this application embodiment, the first recess extends into the first connecting portion.

[0011] In the above technical solution, by extending the first recess into the first connecting portion, during manufacturing, energy can be directly applied from the first recess to the first substrate and / or the center pin, and is not easily blocked or dispersed by the second coating and / or the first coating, so that the first substrate and the center pin are connected to form the first connecting portion, which is beneficial to improving the connection efficiency and connection quality.

[0012] As an optional technical solution in this application embodiment, the first connecting part includes a first part and a second part connected together, the first coating surrounds the first part, the second part is embedded in the central pin, and the first recess extends into the first part and is at a distance from the second part.

[0013] In the above technical solution, the first recess extends into the first part and is at a distance from the second part. In this way, during the formation of the first recess, a part of the first coating will be damaged. During manufacturing, energy can be directly applied to the first substrate from the first recess and conducted to the center pin, and is not easily blocked or dispersed by the second coating and the first coating. This allows the first substrate and the center pin to connect to form the first connection part. Furthermore, the first coating surrounds the first part, which is beneficial to improving the connection efficiency and connection quality.

[0014] As an optional technical solution in this application embodiment, the first connecting part includes a first part and a second part connected together, the first coating surrounds the first part, the second part is embedded in the central pin, and the first recess extends into the second part.

[0015] In the above technical solution, the first recess extends into the second part. In this way, during the formation of the first recess, a part of the first coating will be damaged. During manufacturing, energy can be directly applied to the first substrate and the center pin from the first recess, and is not easily blocked or dispersed by the second coating and the first coating. This allows the first substrate and the center pin to connect to form the first connecting part, which is beneficial to improving the connection efficiency and connection quality.

[0016] As an optional technical solution in this application embodiment, the first recess is columnar.

[0017] In the above technical solution, when the first recess is columnar, the wall area of ​​the first recess is large. During manufacturing, energy can more easily act directly from the first recess onto the first substrate, and is less likely to be blocked and dispersed by the second coating. This allows the first substrate and the central pin to connect to form the first connecting part, which is beneficial to improving the connection efficiency and connection quality.

[0018] As an optional technical solution in this application embodiment, the first recess is a cone-shaped portion whose diameter gradually decreases along the direction from the first surface toward the central needle.

[0019] In the above technical solution, when the first recess is a cone with a diameter that gradually decreases along the direction of the first surface towards the center needle, the first recess can be formed by processing cone-shaped convex teeth, which has low puncture resistance and is easy to manufacture.

[0020] As an optional technical solution in this application embodiment, the first recess includes a first segment and a second segment. One end of the first segment extends to the first surface, and the other end of the first segment is connected to the second segment. The first segment is columnar, and the second segment is conical with a diameter that gradually decreases along the direction from the first surface toward the central needle.

[0021] In the above technical solution, the first segment is columnar and the second segment is conical, which reduces puncture resistance and makes it easy to manufacture. Furthermore, the wall area of ​​the first recess is large, making it easier for energy to act directly on the first substrate during manufacturing, rather than being blocked and dispersed by the second coating. This allows the first substrate and the central needle to connect to form the first connecting part, which is beneficial to improving connection efficiency and connection quality.

[0022] As an optional technical solution in this application embodiment, a portion of the first connecting part is embedded in the central pin.

[0023] In the above technical solution, by embedding a portion of the first connecting part inside the center needle, it is beneficial to enhance the connection strength between the first substrate and the center needle, reduce the risk of the first separator detaching from the center needle during the winding process, and improve the winding quality.

[0024] As an optional technical solution in this application embodiment, the electrode assembly further includes a second separator, which is located on the side of the first separator facing away from the center pin. The first electrode, the first separator, the second electrode, and the second separator are all wound around the outer periphery of the center pin. The second separator includes a second substrate and a third coating, which is disposed on the surface of the second substrate facing the center pin. The battery cell includes a second connecting portion, which is connected to the surface of the second substrate facing the center pin and passes through the third coating to connect with the first substrate.

[0025] In the above technical solution, by providing a second isolator that cooperates with the first isolator, the first electrode and the second electrode are insulated and isolated, reducing the risk of short circuit due to contact between the first and second electrode. By providing a second connecting part to connect the second substrate and the first substrate, the connection strength between the second isolator and the first isolator can be enhanced, reducing the risk of the second isolator detaching from the first isolator during winding, which is beneficial to improving winding quality.

[0026] As an optional technical solution in this application embodiment, the first isolation member includes a second coating, the second coating is disposed on the surface of the first substrate opposite to the central pin, and the second connecting portion passes through the third coating and the second coating and is connected to the first substrate.

[0027] In the above technical solution, by setting the second and third coatings, the mechanical strength and puncture resistance of the first and second spacers can be improved, thermal stability can be enhanced, and electrolyte wettability and retention can be strengthened. By allowing the second connecting portion to pass through the third and second coatings and connect with the first substrate, the connection strength between the second and first spacers can be strengthened, reducing the risk of the second spacer detaching from the first spacer during winding, which is beneficial to improving winding quality.

[0028] As an optional technical solution in this application embodiment, the first isolation member is provided with a first recess at a position corresponding to the first connecting portion, and a portion of the first recess is located in the first substrate; the second isolation member is provided with a through hole at a position corresponding to the first recess, the through hole penetrating the second substrate and the second connecting portion, and the through hole communicating with the first recess.

[0029] In the above technical solution, by providing a through hole at the position corresponding to the first recess on the second spacer and the first recess at the position corresponding to the first connecting part on the first spacer, energy can be directly applied to the first substrate from the first recess during manufacturing, and is less likely to be blocked or dispersed by the second and third coatings. This allows the first substrate and the center pin to connect to form the first connecting part, which is beneficial for improving connection efficiency and connection quality. Furthermore, energy can be directly applied to the first and second substrates from the through hole and the first recess, and is less likely to be blocked or dispersed by the third coating. This allows the first and second substrates to connect to form the second connecting part, which is beneficial for improving connection efficiency and connection quality.

[0030] As an optional technical solution in this application embodiment, the second isolation member includes a fourth coating, which is disposed on the surface of the second substrate away from the central pin, and the through hole penetrates the fourth coating, the second substrate and the second connecting portion.

[0031] In the above technical solution, by setting a fourth coating, the mechanical strength and puncture resistance of the second separator can be improved, thermal stability can be enhanced, and electrolyte wettability and retention can be strengthened. By making the through hole penetrate the fourth coating, the second substrate, and the second connecting part, energy can be directly applied to the first substrate and the second substrate from the through hole and the first recess, and is not easily blocked or dispersed by the third and fourth coatings. This allows the first substrate and the second substrate to connect to form the second connecting part, which is beneficial to improving connection efficiency and connection quality.

[0032] As an optional technical solution in this application embodiment, the first isolation member includes at least one row of first connecting portions, each row of first connecting portions includes a plurality of first connecting portions, and the plurality of first connecting portions are spaced apart along the extension direction of the winding axis of the electrode assembly.

[0033] In the above technical solution, by providing multiple first connecting portions, each of which can connect the first substrate and the center pin, the connection strength between the first isolator and the center pin can be further improved, reducing the risk of the first isolator detaching from the center pin during winding and thus improving winding quality. Furthermore, the multiple first connecting portions are spaced apart along the extension direction of the winding axis of the electrode assembly, which helps reduce the risk of the first isolator wrinkling during winding and further improves winding quality.

[0034] As an optional technical solution in this application embodiment, the first isolation member includes multiple rows of the first connecting portions, which are spaced apart along the winding direction of the first isolation member.

[0035] In the above technical solution, by setting multiple rows of first connecting parts, each row of first connecting parts can connect the first substrate and the center pin, which can further improve the connection strength between the first spacer and the center pin, reduce the risk of the first spacer detaching from the center pin during winding, and help improve winding quality. In addition, the multiple rows of first connecting parts are spaced apart along the winding direction of the first spacer, which helps reduce the risk of the first spacer slipping during winding, and helps improve winding quality.

[0036] As an optional technical solution in this application embodiment, the first connecting part is thermally fused to the central pin.

[0037] In the above technical solution, the first connecting part is heat-fused to the center pin, which is simple, convenient and has a low manufacturing cost.

[0038] As an optional technical solution in this application embodiment, the first connecting part is welded to the center pin.

[0039] In the above technical solution, welding the first connecting part and the center pin together helps to improve the connection strength between the first connecting part and the center pin.

[0040] Secondly, embodiments of this application also provide a battery device, which includes the aforementioned battery cell.

[0041] Thirdly, embodiments of this application also provide an electrical device, which includes the aforementioned battery cell, and the battery cell is used to provide electrical energy to the electrical device.

[0042] Fourthly, embodiments of this application also provide a winding device, the winding device comprising a first providing mechanism, a second providing mechanism, a third providing mechanism, and a fourth providing mechanism. The first providing mechanism is used to provide a first electrode sheet; the second providing mechanism is used to provide a second electrode sheet, the second electrode sheet having the opposite polarity to the first electrode sheet; the third providing mechanism is used to provide a first insulating member, the first insulating member comprising a first substrate and a first coating, the first coating being disposed on the surface of the first substrate; the fourth providing mechanism is used to provide a center pin; the connecting mechanism includes a connecting head having a plurality of protruding teeth, the connecting head being used to connect the first substrate and the center pin after the protruding teeth pierce the first substrate and the first coating to form a first connecting portion, the first connecting portion passing through the first coating; the winding mechanism is used to drive the center pin to rotate, so that the first electrode sheet, the first insulating member, and the second electrode sheet are wound around the outer periphery of the center pin; wherein, the first coating is disposed on the surface of the first substrate facing the center pin.

[0043] As an optional technical solution in this application embodiment, the connecting mechanism includes a heating unit, which is used to heat the connector head so that the connector head heat-melts the first substrate and the center pin through the first connecting portion.

[0044] In the above technical solution, by setting a heating unit, the heating unit can heat the connector, thereby realizing the thermal fusion connection between the first substrate and the center pin, which is simple, convenient and has a low manufacturing cost.

[0045] As an optional technical solution in this application embodiment, the connector is detachably connected to the heating unit.

[0046] In the above technical solution, by making the connector and the heating unit detachably connected, it is easy to replace the connector when it is damaged, which helps to reduce maintenance costs.

[0047] As an optional technical solution in this application embodiment, the connector includes a body portion, the body portion having a pressing surface, the protruding teeth being disposed on the pressing surface, and the protruding teeth and / or the pressing surface being provided with an anti-stick coating.

[0048] In the above technical solution, by setting an anti-stick coating on the protruding teeth and the pressing surface, it is beneficial to reduce the risk of adhesion to the first separator, reduce the risk of damaging the first separator, and improve the winding quality. Attached Figure Description

[0049] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 This application provides structural schematic diagrams of vehicles for some embodiments;

[0051] Figure 2 Exploded views of battery devices provided in some embodiments of this application;

[0052] Figure 3 Exploded views of a single battery cell provided in some embodiments of this application;

[0053] Figure 4 This is a schematic diagram of the structure of an electrode assembly provided in some embodiments of this application;

[0054] Figure 5 A cross-sectional view of the connection between the first spacer and the center pin provided in some embodiments of this application;

[0055] Figure 6 A cross-sectional view of the connection between the first spacer and the center pin provided in some other embodiments of this application;

[0056] Figure 7 A cross-sectional view of the connection between the first spacer and the center pin provided for some embodiments of this application;

[0057] Figure 8 A cross-sectional view of the connection between the first spacer and the center pin provided in some embodiments of this application;

[0058] Figure 9 A cross-sectional view of the first spacer and the connection between the center pin (the first recess includes a first segment and a second segment) provided for some embodiments of this application;

[0059] Figure 10 A cross-sectional view of the connection between the first spacer, the second spacer, and the center pin provided in some embodiments of this application;

[0060] Figure 11 A cross-sectional view showing the connection between the first spacer, the second spacer, and the center pin, as provided in other embodiments of this application;

[0061] Figure 12 This is a schematic diagram showing the arrangement of the first connecting portion provided in some embodiments of this application;

[0062] Figure 13 Schematic block diagram of a winding apparatus provided in some embodiments of this application;

[0063] Figure 14 This is a schematic diagram of the structure of a winding device provided in some embodiments of this application;

[0064] Figure 15 This is a schematic diagram of the connection mechanism provided in some embodiments of this application;

[0065] Figure 16 This is a schematic block diagram of a connection mechanism provided in some embodiments of this application.

[0066] Icons: 10-Box body; 11-First box body; 12-Second box body; 20-Battery cell; 21-Outer shell; 211-Housing shell; 212-End cap; 22-Electrode assembly; 221-Main body; 2211-First electrode; 2212-Second electrode; 2213-Center pin; 2214-First separator; 22141-First substrate; 22142-First coating; 22143-Second coating; 22144-First recess; 221441-First section; 221442-Second section; 221431-First surface; 2215-Second separator; 22151-Second substrate; 22152-Third coating; 22153-Fourth coating; 22154-Through hole; 222 - Tab; 2221- First tab; 2222- Second tab; 23- Electrode terminal; 24- Current collector; 241- First current collector; 242- Second current collector; 25- First connecting part; 251- First section; 252- Second section; 26- Second connecting part; 30- Winding device; 31- First supplying mechanism; 32- Second supplying mechanism; 33- Third supplying mechanism; 34- Fourth supplying mechanism; 35- Connecting mechanism; 351- Connector; 3511- Pressing surface; 352- Tooth; 353- Drive unit; 354- Heating unit; 36- Winding mechanism; 37- Fifth supplying mechanism; 100- Battery device; 200- Controller; 300- Motor; 1000- Vehicle. Detailed Implementation

[0067] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0068] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0069] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0070] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0071] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0072] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0073] In this application, "multiple" means two or more (including two).

[0074] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0075] Battery cells include, 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-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0076] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, reduces the risk of short circuits while allowing active ions to pass through.

[0077] In some embodiments, the positive electrode can be a positive electrode sheet, which may include a positive current collector and a positive active material disposed on at least one surface of the positive current collector.

[0078] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0079] As an example, the positive electrode current collector can be a foil or a composite current collector. For example, as a foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, or titanium, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can 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.).

[0080] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials in battery cells may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide 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, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3Mn 1 / 3O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al 0.05 At least one of O2 and its modified compounds.

[0081] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloys, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, lithium source material, potassium metal, or sodium metal can also be filled and / or deposited within the foamed metal, where the lithium source material is lithium metal and / or a lithium-rich material.

[0082] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative current collector.

[0083] As an example, the negative electrode current collector can be a foil, a foamed metal, or a composite current collector. For example, as a foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, or titanium, etc. The foamed metal can be nickel foam, copper foam, aluminum foam, foam alloy, etc. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper 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.).

[0084] As an example, the negative electrode sheet may include a negative current collector and a negative active material disposed on at least one surface of the negative current collector.

[0085] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0086] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. 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, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials in battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0087] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0088] In some embodiments, the separator is a separator membrane. The separator membrane can be any known porous structure separator membrane with good chemical and mechanical stability.

[0089] As an example, the material of the separator may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or it may be attached to the surfaces of the positive and negative electrodes.

[0090] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0091] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel-like, or solid. Liquid electrolytes include electrolyte salts and solvents.

[0092] In some embodiments, the electrolyte salt may include 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 difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0093] In some embodiments, the solvent may include at least one selected from ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more selected from ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0094] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0095] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0096] As an example, polymer solid electrolytes can be polyethers (polyoxyethylene), polysiloxanes, polycarbonates, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0097] As an example, inorganic solid electrolytes may include one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphate sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0098] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0099] In some embodiments, the electrode assembly is a wound structure. The positive electrode and the negative electrode are wound into a wound structure.

[0100] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0101] In some implementations, the electrode assembly has tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0102] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing may be made of steel, aluminum, or a composite metal (such as a copper-aluminum composite housing).

[0103] In some embodiments, the housing can be a sealed structure or a non-sealed structure. As an example, when the housing is a sealed structure, it can protect the electrode assembly and prevent, to some extent, electrolyte leakage. When the housing is a non-sealed structure, it can still protect the electrode assembly, and a sealing bag may be included between the housing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag can be a bag-shaped insulating component or an aluminum-plastic film.

[0104] As an example, a battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic battery cells, such as hexagonal prismatic battery cells.

[0105] The battery device mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0106] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging multiple battery cells and fixing them together to form an independent module.

[0107] As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0108] In some embodiments, the battery device may be a battery pack, which may include a housing and one or more individual battery cell assemblies housed within the housing.

[0109] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0110] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0111] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first enclosure may be a top cover or a bottom plate.

[0112] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0113] As an example, the housing can be part of the vehicle's chassis structure. For instance, the housing's roof can be at least part of the vehicle's floor, or the housing's frame can be at least part of the vehicle's crossbeams and longitudinal beams.

[0114] In some embodiments, the battery device refers to an energy storage device, which includes a housing with a door on at least one side. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0115] Currently, judging from market trends, battery applications are becoming increasingly widespread. Batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of battery applications, market demand is also constantly increasing.

[0116] The development of battery technology must consider multiple design factors simultaneously, such as energy density, discharge capacity, and charge / discharge rate. Additionally, battery reliability must also be considered. However, current battery reliability is relatively poor.

[0117] In related technologies, when manufacturing wound electrode assemblies, the separator is first wound around a winding needle 1-3 times, and then the positive and negative electrode sheets are fed in separately for winding, ultimately forming a wound electrode assembly. However, the inner ring of the wound electrode assembly lacks support, and during the cycling process of a single battery cell, the inner ring of the electrode assembly is prone to collapse, causing a short circuit and resulting in poor battery reliability.

[0118] To improve battery reliability, a center pin can be placed on the inner side of the wound electrode assembly. During manufacturing, the separator is first fixed to the center pin. Then, the positive electrode, separator, and negative electrode are wound around the outside of the center pin. The center pin supports the positive electrode, separator, and negative electrode, thereby reducing the risk of inner ring collapse. However, the separator consists of a substrate and a coating. The coating is applied to the surface of the substrate. Due to the presence of the coating, the connection strength between the separator and the center pin is low, causing the separator to easily separate from the center pin during winding. This results in poor winding quality and lower battery reliability.

[0119] Therefore, this application provides a battery cell including an electrode assembly and a first connecting portion. The electrode assembly includes a first electrode, a second electrode, a center pin, and a first separator. The first and second electrodes have opposite polarities, and the first electrode, the first separator, and the second electrode are all wound around the outer periphery of the center pin. The first separator includes a first substrate and a first coating, with the first coating disposed on the surface of the first substrate facing the center pin. The first connecting portion is connected to the first substrate and passes through the first coating to connect to the center pin.

[0120] By winding the first electrode, the first separator, and the second electrode around the outer periphery of the center pin, the center pin provides support for these components, reducing the risk of inner ring collapse in the electrode assembly and improving the reliability of the battery cell. By providing a first connecting portion that passes through the first coating and connects to the center pin, a connection between the first substrate and the center pin is achieved, enhancing the connection strength between the first separator and the center pin. Thus, during winding, the first separator is less likely to detach from the center pin, and the first electrode, the second electrode, and the first separator can be firmly wound around the center pin under tension, reducing the risk of slippage and lithium plating, thereby improving the reliability of the battery cell.

[0121] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery cells and battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft.

[0122] For ease of explanation, the following embodiments will use a vehicle as an example of an electrical device.

[0123] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. A battery device 100 is disposed inside the vehicle 1000, and the battery device 100 may 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 the operating power source for the vehicle 1000.

[0124] The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, for the power needs of the vehicle 1000 during startup, navigation and driving.

[0125] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0126] Please refer to Figure 2 , Figure 2 This is an exploded view of a battery device 100 provided in some embodiments of this application. The battery device 100 may include a housing 10 and battery cells 20, the housing 10 being used to house the battery cells 20.

[0127] The housing 10 has an enclosed space inside for accommodating the battery cells 20. The housing 10 can have various structures. In some embodiments, the housing 10 may include a first housing body 11 and a second housing body 12, which are interlocked. The first housing body 11 and the second housing body 12 can have various shapes, such as cuboids or cylinders. The first housing body 11 can be a hollow structure open on one side, and the second housing body 12 can also be a hollow structure open on one side. The open side of the second housing body 12 interlocks with the open side of the first housing body 11, thus forming a housing 10 with an enclosed space. Alternatively, the first housing body 11 can be a hollow structure open on one side, and the second housing body 12 can be a plate-like structure, with the second housing body 12 interlocked with the open side of the first housing body 11, thus forming a housing 10 with an accommodating chamber.

[0128] In the battery device 100, there can be one or more battery cells 20. If there are multiple battery cells 20, they can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 20 are connected in both series and parallel. Alternatively, multiple battery cells 20 can be first connected in series, parallel, or in a mixed configuration to form a battery module, and then multiple battery modules can be connected in series, parallel, or in a mixed configuration to form a whole, which is then housed within the housing 10. Another option is that all battery cells 20 can be directly connected in series, parallel, or in a mixed configuration, and then the whole consisting of all battery cells 20 is housed within the housing 10.

[0129] In some embodiments, the battery device 100 may further include a busbar component, through which multiple battery cells 20 can be electrically connected to each other to achieve series, parallel, or mixed connection of the multiple battery cells 20. The busbar component may be a metallic conductor, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0130] Please refer to Figure 3 , Figure 4 and Figure 5 , Figure 3 An exploded view of a battery cell 20 provided in some embodiments of this application. Figure 4 This is a schematic diagram of the structure of the electrode assembly 22 provided in some embodiments of this application. Figure 5This is a cross-sectional view showing the connection between the first separator 2214 and the center pin 2213 according to some embodiments of this application. Embodiments of this application provide a battery cell 20, which includes an electrode assembly 22 and a first connecting portion 25. The electrode assembly 22 includes a first electrode 2211, a second electrode 2212, a center pin 2213, and a first separator 2214. The first electrode 2211 and the second electrode 2212 have opposite polarities, and both the first electrode 2211, the first separator 2214, and the second electrode 2212 are wound around the outer periphery of the center pin 2213. The first separator 2214 includes a first substrate 22141 and a first coating 22142, with the first coating 22142 disposed on the surface of the first substrate 22141 facing the center pin 2213. The first connecting portion 25 is connected to the first substrate 22141 and passes through the first coating 22142 to connect to the center pin 2213.

[0131] Battery cell 20 refers to the smallest unit that makes up battery device 100.

[0132] The housing 21 includes a housing 211 and an end cap 212. The housing 211 has a receiving space with an opening at one end for accommodating the electrode assembly 22. The end cap 212 is connected to the housing 211 and closes the opening.

[0133] End cap 212 refers to a component that covers the opening of housing 211 to isolate the internal environment of battery cell 20 from the external environment. The shape of end cap 212 can be adapted to the shape of housing 211 to fit it. Optionally, end cap 212 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that end cap 212 is less prone to deformation under pressure and impact, enabling battery cell 20 to have higher structural strength and improved reliability. The material of end cap 212 can include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, and plastic.

[0134] The housing 211 is a component used to cooperate with the end cap 212 to form the internal environment of the battery cell 20. This internal environment can accommodate the electrode assembly 22, electrolyte, and other components. The housing 211 and the end cap 212 can be independent components. An opening can be provided on the housing 211, and the end cap 212 can be used to close the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 212 and the housing 211 can be integrated. Specifically, the end cap 212 and the housing 211 can form a common mating surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 211, the end cap 212 closes the housing 211. The housing 211 can have various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 211 can be determined according to the specific shape and size of the electrode assembly 22. The material of the housing 211 can include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0135] In some embodiments, the housing 211 may have an opening at only one end, with one end cap 212 correspondingly provided. In other embodiments, the housing 211 may have openings at both ends, with two end caps 212 correspondingly provided, the two end caps 212 respectively closing the two opposite openings of the housing 211. Figure 3 and Figure 4 In the embodiment shown, the housing 211 has an opening at only one end, and an end cap 212 is provided accordingly.

[0136] Electrode assembly 22 is the component in the battery cell 20 where electrochemical reactions occur. The housing 211 may contain one or more electrode assemblies 22. The electrode assembly 22 is mainly formed by winding or stacking positive and negative electrode sheets, and typically a separator is provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body 221 of the electrode assembly 22, while the portions of the positive and negative electrode sheets without active material each constitute a tab 222. The positive and negative tabs may be located together at one end of the main body 221 or separately at both ends of the main body 221. During the charging and discharging process of the battery cell 20, the positive and negative active materials react with the electrolyte.

[0137] The battery cell 20 includes an electrode terminal 23, which is disposed on the housing 21. The electrode terminal 23 is used to electrically connect with the tab 222 of the electrode assembly 22 to input or output electrical energy of the battery cell 20.

[0138] Electrode terminal 23 and tab 222 can be directly connected, for example, by welding electrode terminal 23 to tab 222. Electrode terminal 23 and tab 222 can also be indirectly connected, for example, by connecting electrode terminal 23 and tab 222 indirectly through current collector 24. Current collector 24 can be a metal conductor, such as copper, iron, aluminum, steel, aluminum alloy, etc. In some embodiments, there is one electrode terminal 23, one tab 222 of electrode assembly 22 (one of the positive tab and the negative tab) can be electrically connected to electrode terminal 23, and the other tab 222 of electrode assembly 22 (the other of the positive tab and the negative tab) can be electrically connected to housing 21.

[0139] As an example, such as Figure 3 and Figure 4 As shown, the housing 211 has an opening at only one end, and there is one end cap 212 covering the opening of the housing 211. Electrode terminals 23 are provided on the walls of the housing 211 opposite to the end cap 212. The electrode assembly 22 has tabs 222 at both ends. The tabs 222 at both ends of the electrode assembly 22 are a first tab 2221 and a second tab 2222, respectively. One of the first tab 2221 and the second tab 2222 is a positive tab, and the other is a negative tab. The electrode terminal 23 is electrically connected to the first tab 2221 through a first current collector 241, and the end cap 212 is electrically connected to the second tab 2222 through a second current collector 242.

[0140] The electrode assembly 22 includes a first electrode 2211 and a second electrode 2212, with opposite polarities. One of the first electrode 2211 and the second electrode 2212 is a positive electrode, and the other is a negative electrode. For example, when the first electrode 2211 is a positive electrode, the second electrode 2212 is a negative electrode. Conversely, when the first electrode 2211 is a negative electrode, the second electrode 2212 is a positive electrode.

[0141] The first separator 2214 is disposed between the positive and negative electrode plates to isolate them and reduce the risk of short circuits between them. The first separator 2214 has a large number of through-holes, which allows metal ions to pass through freely and has good permeability to metal ions.

[0142] The first substrate 22141 is the base portion of the first separator 2214. The first substrate 22141 acts as a physical barrier, isolating the positive and negative electrodes and reducing the risk of short circuits caused by direct contact between them. The micropores of the first substrate 22141 allow electrolyte wetting, enabling metal ions to freely pass through and complete the charging and discharging process. The material of the first substrate 22141 may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride.

[0143] The first coating 22142 is disposed on the surface of the first substrate 22141 facing the central pin 2213. The first coating 22142 can compensate for certain shortcomings of the first substrate 22141 in terms of performance, such as poor thermal stability, insufficient mechanical strength, and poor affinity with electrolyte. The material of the first coating 22142 may include at least one of alumina, silicon oxide, boehmite, barium sulfate, zirconium oxide, silicon oxide, magnesium oxide, zinc oxide, and tin oxide.

[0144] Please refer to Figure 4 ,exist Figure 4 In the diagram, to facilitate the distinction between the first electrode 2211, the second electrode 2212, and the first separator 2214, the first electrode 2211 is represented by a thin solid line, the second electrode 2212 by a thick solid line, and the first separator 2214 by a dashed line. It should be noted that the thin solid lines, thick solid lines, and dashed lines are only for ease of distinction and do not represent any other meaning.

[0145] The center pin 2213 is disposed on the inner side of the electrode assembly 22. The first electrode 2211, the first separator 2214, and the second electrode 2212 are all wound around the center pin 2213. The center pin 2213 can support the first electrode 2211, the first separator 2214, and the second electrode 2212, so that the first electrode 2211, the first separator 2214, and the second electrode 2212 are firmly wound around the center pin 2213 under tension. This helps to reduce the risk of slippage of the first electrode 2211, the first separator 2214, and the second electrode 2212, which helps to reduce the risk of lithium plating and improve the reliability of the battery cell 20. The center pin 2213 can be made of metal or plastic.

[0146] Please refer to Figure 4 ,exist Figure 4In the illustrated embodiment, the center pin 2213 has a columnar structure, and its outer peripheral surface is cylindrical to facilitate the winding of the first electrode 2211, the first spacer 2214, and the second electrode 2212 around the outer peripheral surface of the center pin 2213. The inner peripheral surface of the center pin 2213 is prismatic to facilitate its cooperation with the winding needle and reduce the risk of relative slippage between the center pin 2213 and the winding needle during the winding process.

[0147] The first connecting portion 25 is a connecting structure that connects the first substrate 22141 and the center pin 2213. One end of the first connecting portion 25 is connected to the first substrate 22141, and the other end of the first connecting portion 25 passes through the first coating 22142 and is connected to the center pin 2213. In some embodiments, during manufacturing, a portion of the first coating 22142 is partially damaged, and the first substrate 22141 and the center pin 2213 are thermally fused or welded together. The first connecting portion 25 is a connecting post formed by the thermally fused or welded connection of the first substrate 22141 and the center pin 2213. In other embodiments, the first coating 22142 is a particulate coating, and the first substrate 22141 has a first exposed area not covered by the first coating 22142. The first exposed area of ​​the first substrate 22141 and the center pin 2213 are thermally fused or welded together. The first connecting portion 25 is a connecting post formed by the thermally fused or welded connection of the first substrate 22141 and the center pin 2213.

[0148] By winding the first electrode 2211, the first separator 2214, and the second electrode 2212 around the outer periphery of the center pin 2213, the center pin 2213 can support the first electrode 2211, the first separator 2214, and the second electrode 2212, thereby reducing the risk of inner ring collapse of the electrode assembly 22 and improving the reliability of the battery cell 20. By providing a first connecting portion 25 and connecting the first connecting portion 25 through the first coating 22142 to the center pin 2213, the connection between the first substrate 22141 and the center pin 2213 is achieved, which helps to improve the connection strength between the first separator 2214 and the center pin 2213. In this way, during the winding process, the first separator 2214 is not easy to detach from the center pin 2213, and the first electrode 2211, the second electrode 2212 and the first separator 2214 can be firmly wound on the center pin 2213 under tension. This helps to reduce the risk of slippage of the first electrode 2211, the second electrode 2212 and the first separator 2214, which helps to reduce the risk of lithium plating and improve the reliability of the battery cell 20.

[0149] Please refer to Figure 3 , Figure 4 and Figure 5In some embodiments, the first separator 2214 includes a second coating 22143, which is disposed on the surface of the first substrate 22141 opposite to the center pin 2213. The second coating 22143 has a first surface 221431 opposite to the first substrate 22141. The first separator 2214 has a first recess 22144 at a position corresponding to the first connecting portion 25. The first recess 22144 is recessed from the first surface 221431 toward the center pin 2213, and a portion of the first recess 22144 is located within the first substrate 22141.

[0150] The second coating 22143 is disposed on the surface of the first substrate 22141 opposite to the central pin 2213. The second coating 22143 can compensate for certain deficiencies in the substrate, such as poor thermal stability, insufficient mechanical strength, and poor affinity with electrolyte. The material of the second coating 22143 may include at least one of alumina, silicon oxide, boehmite, barium sulfate, zirconium oxide, silicon oxide, magnesium oxide, zinc oxide, and tin oxide.

[0151] The first surface 221431 is the surface of the second coating 22143 facing away from the first substrate 22141. The first surface 221431 is provided with a first recess 22144, which is recessed from the first surface 221431 towards the center pin 2213. The position of the first recess 22144 corresponds to the position of the first connecting portion 25. In some embodiments, a portion of the first recess 22144 is located in the second coating 22143, and another portion is located in the first substrate 22141. In other embodiments, a portion of the first recess 22144 is located in the second coating 22143, another portion is located in the first substrate 22141, and yet another portion is located within the first connecting portion 25.

[0152] By providing a first recess 22144 and recessing it from the first surface 221431 toward the center pin 2213, with a portion of the first recess 22144 located within the first substrate 22141, energy can be directly applied to the first substrate 22141 from the first recess 22144 during manufacturing, and is less likely to be blocked and dispersed by the second coating 22143. This allows the first substrate 22141 and the center pin 2213 to connect to form the first connecting portion 25, which is beneficial for improving connection efficiency and connection quality.

[0153] Please refer to Figure 3 , Figure 4 and Figure 5 In some embodiments, the depth of the first recess 22144 is less than the sum of the thickness of the first substrate 22141 and the thickness of the second coating 22143.

[0154] "The depth of the first recess 22144 is less than the sum of the thickness of the first substrate 22141 and the thickness of the second coating 22143". That is, a part of the first recess 22144 is located in the second coating 22143, and another part of the first recess 22144 is located in the first substrate 22141. The first recess 22144 does not penetrate the first substrate 22141.

[0155] By making the depth of the first recess 22144 less than the sum of the thickness of the first substrate 22141 and the thickness of the second coating 22143, it is beneficial to make the strength of the first substrate 22141 higher and reduce the risk of the first substrate 22141 tearing during the winding process.

[0156] Please refer to Figure 6 , Figure 6 A cross-sectional view showing the connection between the first spacer 2214 and the center pin 2213 as provided in other embodiments of this application. In other embodiments, the first recess 22144 extends into the first connecting portion 25.

[0157] A portion of the first recess 22144 is located in the second coating 22143, another portion of the first recess 22144 is located in the first substrate 22141, and yet another portion of the first recess 22144 is located within the first connecting portion 25.

[0158] By extending the first recess 22144 into the first connecting portion 25, during manufacturing, energy can be directly applied from the first recess 22144 to the first substrate 22141 and / or the center pin 2213, and is less likely to be blocked and dispersed by the second coating 22143 and / or the first coating 22142, so that the first substrate 22141 and the center pin 2213 are connected to form the first connecting portion 25, which is beneficial to improving connection efficiency and connection quality.

[0159] Please refer to Figure 6 In some embodiments, the first connecting portion 25 includes a first portion 251 and a second portion 252 connected together, a first coating 22142 surrounding the first portion 251, and the second portion 252 being embedded in the central pin 2213. A first recess 22144 extends into the first portion 251 and is spaced apart from the second portion 252.

[0160] The first portion 251 is the part of the first connecting portion 25 located within the first coating 22142, and the second portion 252 is the part of the first connecting portion 25 embedded within the central pin 2213. The first portion 251 and the second portion 252 are connected. The first recess 22144 extends into the first portion 251 but does not extend into the second portion 252. In other words, the first recess 22144 has a portion located within the first portion 251, but does not have a portion located within the second portion 252.

[0161] The first recess 22144 extends into the first portion 251 and is at a distance from the second portion 252. Thus, during the formation of the first recess 22144, a portion of the first coating 22142 is damaged. During manufacturing, energy can be directly applied from the first recess 22144 to the first substrate 22141 and conducted to the center pin 2213, without being easily blocked or dispersed by the second coating 22143 and the first coating 22142. This allows the first substrate 22141 and the center pin 2213 to connect to form the first connecting portion 25. Furthermore, the first coating 22142 surrounds the first portion 251, which helps to improve the connection efficiency and connection quality.

[0162] Please refer to Figure 7 , Figure 7 A cross-sectional view showing the connection between a first spacer 2214 and a center pin 2213, provided for some embodiments of this application. In some embodiments, the first connecting portion 25 includes a first portion 251 and a second portion 252 connected together, a first coating 22142 surrounding the first portion 251, and the second portion 252 being embedded within the center pin 2213. A first recess 22144 extends into the second portion 252.

[0163] A portion of the first recess 22144 is located in the second coating 22143, another portion of the first recess 22144 is located in the first substrate 22141, and yet another portion of the first recess 22144 is located within the first connecting portion 25. Within the portion of the first recess 22144 located within the first connecting portion 25, a portion of the first recess 22144 is located within the first portion 251, and another portion of the first recess 22144 is located within the second portion 252.

[0164] The first recess 22144 extends into the second portion 252. In this way, during the formation of the first recess 22144, a portion of the first coating 22142 is damaged. During manufacturing, energy can be directly applied from the first recess 22144 to the first substrate 22141 and the center pin 2213, and is not easily blocked or dispersed by the second coating 22143 and the first coating 22142. This allows the first substrate 22141 and the center pin 2213 to connect to form the first connecting portion 25, which is beneficial to improving the connection efficiency and connection quality.

[0165] Please refer to Figure 8 , Figure 8 A cross-sectional view showing the connection between the first spacer 2214 and the center pin 2213 provided in some embodiments of this application. In some embodiments, the first recess 22144 is columnar.

[0166] The first recess 22144 can be cylindrical or prismatic.

[0167] When the first recess 22144 is columnar, the wall area of ​​the first recess 22144 is larger. During manufacturing, energy can more easily act directly from the first recess 22144 to the first substrate 22141, and is less likely to be blocked and dispersed by the second coating 22143. This allows the first substrate 22141 and the center pin 2213 to connect to form the first connecting part 25, which is beneficial to improving the connection efficiency and connection quality.

[0168] Please refer to this again. Figure 7 In some embodiments, the first recess 22144 is a cone with a diameter that gradually decreases along the direction from the first surface 221431 toward the center needle 2213.

[0169] The first recess 22144 can be a pyramidal shape with a diameter that gradually decreases along the direction from the first surface 221431 to the center pin 2213, or it can be a conical shape with a diameter that gradually decreases along the direction from the first surface 221431 to the center pin 2213. It should be noted that a frustum can also be considered as a pyramidal shape, and a frustum can also be considered as a conical shape.

[0170] When the first recess 22144 is a cone with a diameter that gradually decreases along the direction from the first surface 221431 toward the center needle 2213, the first recess 22144 can be formed by processing cone-shaped protrusions 352, resulting in low puncture resistance and ease of manufacturing.

[0171] Please refer to Figure 9 , Figure 9 A cross-sectional view of the connection between the first spacer 2214 and the center pin 2213 (the first recess 22144 includes a first segment 221441 and a second segment 221442) provided in some embodiments of this application. In some embodiments, the first recess 22144 includes a first segment 221441 and a second segment 221442, one end of the first segment 221441 extending to a first surface 221431, and the other end of the first segment 221441 connecting to the second segment 221442. The first segment 221441 is columnar, and the second segment 221442 is conical, with its diameter gradually decreasing along the direction from the first surface 221431 toward the center pin 2213.

[0172] The first segment 221441 is a columnar part in the first recess 22144, and the second segment 221442 is a conical part in the first recess 22144. One end of the first segment 221441 extends to the first surface 221431, and the other end of the first segment 221441 is connected to the larger end of the second segment 221442.

[0173] The first segment 221441 is columnar and the second segment 221442 is conical, resulting in low puncture resistance and ease of manufacturing. Furthermore, the first recess 22144 has a large wall area, allowing energy to more easily act directly from the first recess 22144 onto the first substrate 22141 during manufacturing, rather than being blocked or dispersed by the second coating 22143. This enables the first substrate 22141 and the central needle 2213 to connect to form the first connecting part 25, which is beneficial for improving connection efficiency and connection quality.

[0174] Please refer to Figure 9 In some embodiments, a portion of the first connecting portion 25 is embedded within the central pin 2213.

[0175] By embedding a portion of the first connecting part 25 within the center pin 2213, the connection strength between the first substrate 22141 and the center pin 2213 is enhanced, the risk of the first isolator 2214 detaching from the center pin 2213 during the winding process is reduced, and the winding quality is improved.

[0176] Please refer to Figure 10 , Figure 10 This is a cross-sectional view showing the connection of a first spacer 2214, a second spacer 2215, and a center pin 2213 according to some embodiments of this application. In some embodiments, the electrode assembly 22 further includes a second spacer 2215, which is located on the side of the first spacer 2214 opposite to the center pin 2213. The first electrode 2211, the first spacer 2214, the second electrode 2212, and the second spacer 2215 are all wound around the outer periphery of the center pin 2213. The second spacer 2215 includes a second substrate 22151 and a third coating 22152, which is disposed on the surface of the second substrate 22151 facing the center pin 2213. The battery cell 20 includes a second connecting portion 26, which is connected to the surface of the second substrate 22151 facing the center pin 2213 and passes through the third coating 22152 to connect to the first substrate 22141.

[0177] The second separator 2215 is disposed between the positive and negative electrode plates to isolate them and reduce the risk of short circuits between them. The second separator 2215 has a large number of through-holes, which allows metal ions to pass through freely and has good permeability to metal ions.

[0178] The second substrate 22151 is the base portion of the second separator 2215. The second substrate 22151 acts as a physical barrier, isolating the positive and negative electrodes and reducing the risk of short circuits caused by direct contact between them. The micropores of the second substrate 22151 allow electrolyte wetting, enabling metal ions to freely pass through and complete the charging and discharging process. The material of the second substrate 22151 may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride.

[0179] The third coating 22152 is disposed on the surface of the second substrate 22151 facing the central pin 2213. The third coating 22152 can compensate for certain shortcomings of the second substrate 22151 in certain properties, such as poor thermal stability, insufficient mechanical strength, and poor affinity with electrolyte. The material of the third coating 22152 may include at least one of alumina, silicon oxide, boehmite, barium sulfate, zirconium oxide, silicon oxide, magnesium oxide, zinc oxide, and tin oxide.

[0180] Please refer to Figure 4 ,exist Figure 4 In the diagram, to facilitate the distinction between the first electrode 2211, the second electrode 2212, the first isolator 2214, and the second isolator 2215, the first electrode 2211 is represented by a thin solid line, the second electrode 2212 by a thick solid line, the first isolator 2214 by a dashed line, and the second isolator 2215 by a dotted line. It should be noted that the thin solid lines, thick solid lines, dashed lines, and dotted lines are only for ease of distinction and do not represent any other meaning.

[0181] The second connecting portion 26 is a connecting structure that connects the first substrate 22141 and the second substrate 22151. One end of the second connecting portion 26 is connected to the second substrate 22151, and the other end of the second connecting portion 26 passes through the third coating 22152 and is connected to the first substrate 22141. In some embodiments, during manufacturing, a portion of the third coating 22152 is partially damaged, and the first substrate 22141 and the second substrate 22151 are thermally fused or welded together. The second connecting portion 26 is a connecting post formed by the thermal fusion or welding of the first substrate 22141 and the second substrate 22151. In other embodiments, the third coating 22152 is a particulate coating, and the second substrate 22151 has a second exposed area not covered by the third coating 22152. The second exposed area of ​​the second substrate 22151 and the first substrate 22141 are thermally fused or welded together. The second connecting portion 26 is a connecting post formed by the thermal fusion or welding of the first substrate 22141 and the second substrate 22151.

[0182] By providing a second isolator 2215, which cooperates with the first isolator 2214, the first electrode 2211 and the second electrode 2212 are insulated and isolated, reducing the risk of short circuit due to contact between the first electrode 2211 and the second electrode 2212. By providing a second connecting portion 26 to connect the second substrate 22151 and the first substrate 22141, the connection strength between the second isolator 2215 and the first isolator 2214 is enhanced, reducing the risk of the second isolator 2215 detaching from the first isolator 2214 during winding, which is beneficial to improving winding quality.

[0183] Please refer to Figure 10 In some embodiments, the first isolation member 2214 includes a second coating 22143, which is disposed on the surface of the first substrate 22141 away from the center pin 2213, and the second connecting portion 26 passes through the third coating 22152 and the second coating 22143 and is connected to the first substrate 22141.

[0184] By providing the second coating 22143 and the third coating 22152, the mechanical strength and puncture resistance of the first separator 2214 and the second separator 2215 can be improved, as well as their thermal stability, electrolyte wettability, and retention capacity. By allowing the second connecting portion 26 to pass through the third coating 22152 and the second coating 22143 and connect with the first substrate 22141, the connection strength between the second separator 2215 and the first separator 2214 can be enhanced, reducing the risk of the second separator 2215 detaching from the first separator 2214 during winding, thus improving winding quality.

[0185] Please refer to Figure 10 In some embodiments, the first spacer 2214 has a first recess 22144 at a position corresponding to the first connecting portion 25, and a portion of the first recess 22144 is located within the first substrate 22141. The second spacer 2215 has a through hole 22154 at a position corresponding to the first recess 22144, the through hole 22154 penetrating the second substrate 22151 and the second connecting portion 26, and the through hole 22154 communicating with the first recess 22144.

[0186] The first recess 22144 may be located only in the first substrate 22141, or the first recess 22144 may be located partly in the first substrate 22141 and partly in the first connecting portion 25.

[0187] The second isolation member 2215 is provided with a through hole 22154, the position of which corresponds to the position of the first recess 22144 and the position of the first connecting part 25. The through hole 22154 penetrates the second substrate 22151 and the second connecting part 26 and communicates with the end of the first recess 22144 away from the first connecting part 25.

[0188] By providing a through hole 22154 at a position corresponding to the first recess 22144 in the second spacer 2215, and a first recess 22144 at a position corresponding to the first connecting portion 25 in the first spacer 2214, energy can be directly applied to the first substrate 22141 from the first recess 22144 during manufacturing, and is less likely to be blocked or dispersed by the second coating 22143 and the third coating 22152. This allows the first substrate 22141 and the center pin 2213 to connect to form the first connecting portion 25, which is beneficial for improving connection efficiency and connection quality. Furthermore, energy can be directly applied to the first substrate 22141 and the second substrate 22151 from the through hole 22154 and the first recess 22144, and is less likely to be blocked or dispersed by the third coating 22152. This allows the first substrate 22141 and the second substrate 22151 to connect to form the second connecting portion 26, which is also beneficial for improving connection efficiency and connection quality.

[0189] Please refer to Figure 11 , Figure 11 A cross-sectional view showing the connection of a first spacer 2214, a second spacer 2215, and a center pin 2213, provided for other embodiments of this application. In some embodiments, the second spacer 2215 includes a fourth coating 22153, which is disposed on the surface of the second substrate 22151 opposite to the center pin 2213, and a through hole 22154 penetrates the fourth coating 22153, the second substrate 22151, and the second connecting portion 26.

[0190] A fourth coating 22153 is disposed on the surface of the second substrate 22151 opposite to the central pin 2213. The fourth coating 22153 can compensate for certain shortcomings of the second substrate 22151 in terms of performance, such as poor thermal stability, insufficient mechanical strength, and poor affinity with electrolyte. The material of the fourth coating 22153 may include at least one of alumina, silicon oxide, boehmite, barium sulfate, zirconium oxide, silicon oxide, magnesium oxide, zinc oxide, and tin oxide.

[0191] By providing the fourth coating 22153, the mechanical strength and puncture resistance of the second insulating member 2215 can be improved, as well as its thermal stability, electrolyte wettability, and retention capacity. By allowing the through-hole 22154 to penetrate the fourth coating 22153, the second substrate 22151, and the second connecting portion 26, energy can be directly applied from the through-hole 22154 and the first recess 22144 to the first substrate 22141 and the second substrate 22151, without being easily blocked or dispersed by the third coating 22152 and the fourth coating 22153. This allows the first substrate 22141 and the second substrate 22151 to connect and form the second connecting portion 26, which is beneficial for improving connection efficiency and connection quality.

[0192] Please refer to Figure 12 , Figure 12 This is a schematic diagram showing the arrangement of the first connecting portions 25 provided in some embodiments of this application. In some embodiments, the first isolation member 2214 includes at least one row of first connecting portions 25, each row of first connecting portions 25 includes a plurality of first connecting portions 25, and the plurality of first connecting portions 25 are spaced apart along the extension direction of the winding axis of the electrode assembly 22.

[0193] Please refer to Figure 12 The extension direction of the winding axis of electrode assembly 22 is the X direction shown in the figure.

[0194] The first spacer 2214 may include one row, two rows, three rows, or more rows of first connecting portions 25. Each row of first connecting portions 25 may include two, three, four, or more first connecting portions 25. Multiple first connecting portions 25 located in the same row are spaced apart along the extension direction of the winding axis of the electrode assembly 22.

[0195] By providing multiple first connecting portions 25, each of which can connect the first substrate 22141 and the center pin 2213, the connection strength between the first isolator 2214 and the center pin 2213 can be further improved, reducing the risk of the first isolator 2214 detaching from the center pin 2213 during winding, which is beneficial to improving winding quality. Furthermore, the multiple first connecting portions 25 are spaced apart along the extension direction of the winding axis of the electrode assembly 22, which helps reduce the risk of the first isolator 2214 wrinkling during winding, further improving winding quality.

[0196] Please refer to Figure 4 and Figure 12 The first isolation member 2214 includes multiple rows of first connecting portions 25, which are spaced apart along the winding direction of the first isolation member 2214.

[0197] Please refer to Figure 4The first spacer 2214 is wound in the Y direction as shown in the figure.

[0198] Multiple rows of first connecting portions 25 are spaced apart along the winding direction of the first separator 2214.

[0199] By providing multiple rows of first connecting portions 25, each row can connect the first substrate 22141 and the center pin 2213, further enhancing the connection strength between the first spacer 2214 and the center pin 2213. This reduces the risk of the first spacer 2214 detaching from the center pin 2213 during winding, thus improving winding quality. Furthermore, the multiple rows of first connecting portions 25 are spaced apart along the winding direction of the first spacer 2214, which helps reduce the risk of slippage of the first spacer 2214 during winding, further improving winding quality.

[0200] In some embodiments, the first connecting portion 25 is heat-fused to the center pin 2213.

[0201] By heat-fusion connecting the first connecting part 25 to the center pin 2213, it is simple, convenient, and has a low manufacturing cost.

[0202] In other embodiments, the first connecting portion 25 is welded to the center pin 2213.

[0203] The first connecting part 25 and the center pin 2213 can be welded together by ultrasonic welding or friction welding.

[0204] By welding the first connecting part 25 and the center pin 2213 together, the connection strength between the first connecting part 25 and the center pin 2213 can be improved.

[0205] This application embodiment also provides a battery device 100, which includes the aforementioned battery cell 20.

[0206] This application embodiment also provides an electrical device, which includes the aforementioned battery cell 20, and the battery cell 20 is used to provide electrical energy to the electrical device.

[0207] Please refer to Figure 13 , Figure 14 and Figure 15 , Figure 13 This is a schematic block diagram of a winding apparatus 30 provided in some embodiments of this application. Figure 14 This is a schematic diagram of the structure of the winding device 30 provided in some embodiments of this application. Figure 15This is a schematic diagram of the connection mechanism 35 provided in some embodiments of this application. In some embodiments, this application also provides a winding device 30, which includes a first providing mechanism 31, a second providing mechanism 32, a third providing mechanism 33, and a fourth providing mechanism 34. The first providing mechanism 31 is used to provide a first electrode 2211. The second providing mechanism 32 is used to provide a second electrode 2212, the second electrode 2212 having the opposite polarity to the first electrode 2211. The third providing mechanism 33 is used to provide a first insulating member 2214, the first insulating member 2214 including a first substrate 22141 and a first coating 22142, the first coating 22142 being disposed on the surface of the first substrate 22141. The fourth providing mechanism 34 is used to provide a center pin 2213. The connecting mechanism 35 includes a connector 351 with multiple protruding teeth 352. The connector 351 is used to connect the first substrate 22141 and the center needle 2213 after the protruding teeth 352 pierce the first substrate 22141 and the first coating 22142, forming a first connecting portion 25. The first connecting portion 25 passes through the first coating 22142. The winding mechanism 36 is used to drive the center needle 2213 to rotate, so that the first electrode 2211, the first separator 2214, and the second electrode 2212 are wound around the outer periphery of the center needle 2213. The first coating 22142 is disposed on the surface of the first substrate 22141 facing the center needle 2213.

[0208] The first providing mechanism 31 is a mechanism for providing the first electrode 2211. In some embodiments, the first providing mechanism 31 includes a first unwinding roller and a first driving member. The first unwinding roller is used to set the first electrode roll, and the first driving member is connected to the first unwinding roller and is used to drive the first unwinding roller to rotate, so as to unwind the first electrode roll and provide the first electrode 2211.

[0209] The second providing mechanism 32 is a mechanism for providing the second electrode 2212. In some embodiments, the second providing mechanism 32 includes a second unwinding roller and a second driving member. The second unwinding roller is used to set the second electrode roll, and the second driving member is connected to the second unwinding roller and is used to drive the second unwinding roller to rotate, so as to unwind the second electrode roll and provide the second electrode 2212.

[0210] The third providing mechanism 33 is a mechanism for providing the first isolation member 2214. In some embodiments, the third providing mechanism 33 includes a third unwinding roller and a third driving member. The third unwinding roller is used to set the first isolation member roll, and the third driving member is connected to the third unwinding roller and is used to drive the third unwinding roller to rotate, so as to unwind the first isolation member roll and provide the first isolation member 2214.

[0211] In some embodiments, the winding device 30 further includes a fifth providing mechanism 37, which is a mechanism for providing the second spacer 2215. In some embodiments, the fifth providing mechanism 37 includes a fourth unwinding roller and a fourth driving member. The fourth unwinding roller is used to set the second spacer roll, and the fourth driving member is connected to the fourth unwinding roller and is used to drive the fourth unwinding roller to rotate, thereby unwinding the second spacer roll to provide the second spacer 2215.

[0212] Please refer to Figure 14 ,exist Figure 14 In the embodiment shown, the first isolation member 2214 provided by the third providing mechanism 33, the first electrode 2211 provided by the first providing mechanism 31, the second isolation member 2215 provided by the fifth providing mechanism 37, and the second electrode 2212 provided by the second providing mechanism 32 are sequentially stacked into the winding mechanism 36 in a counterclockwise direction.

[0213] Please refer to Figure 14 ,exist Figure 14 In the embodiment shown, the third providing mechanism 33, the first providing mechanism 31, the fifth providing mechanism 37, and the second providing mechanism 32 are arranged in a counterclockwise direction.

[0214] The fourth providing mechanism 34 is a mechanism for providing the center needle 2213. In some embodiments, the fourth providing mechanism 34 is a robotic arm for picking up the center needle 2213. In other embodiments, the fourth providing mechanism 34 is a container for holding the center needle 2213. For example, the fourth providing mechanism 34 is a feed box for holding the center needle 2213. Please refer to... Figure 14 ,exist Figure 14 In the embodiment shown, the fourth providing mechanism 34 includes a robotic arm that picks up the center needle 2213 and places it at a preset position so that the center needle 2213 can cooperate with the winding mechanism 36.

[0215] The connecting mechanism 35 is used to connect the first isolator 2214 to the center pin 2213. The connecting mechanism 35 includes a connector 351, which is the main component for connecting the first isolator 2214 and the center pin 2213. The connector 351 can be a thermoforming head, an ultrasonic welding head, or a friction welding head.

[0216] The connector 351 has multiple protruding teeth 352, which are used to pierce the first substrate 22141 and the first coating 22142 and release energy to connect the first substrate 22141 and the central pin 2213 to form a first connecting portion 25. The protruding teeth 352 can be conical, pyramidal, or cylindrical. They can also be columnar, prismatic, or cylindrical. Furthermore, one part of the protruding tooth 352 can be conical and the other part columnar.

[0217] In some embodiments, the height of the protrusion 352 is less than the minimum wall thickness of the center needle 2213 to reduce the risk of the protrusion 352 puncturing the center needle 2213.

[0218] Please refer to Figure 15 In some embodiments, the connecting mechanism 35 further includes a drive unit 353 connected to the connector 351. The drive unit 353 drives the connector 351 to move closer to or away from the center pin 2213. The drive unit 353 can drive the connector 351 to move along a linear trajectory. For example, the drive unit 353 includes a linear drive member, the output end of which is connected to the connector 351. The linear drive member outputs linear motion to drive the connector 351 to move closer to or away from the center pin 2213 along a linear trajectory. The linear drive member can be a linear cylinder, a linear electric cylinder, a linear hydraulic cylinder, etc. The drive unit 353 can also include a rotary drive member and a transmission mechanism. The rotary drive member is connected to the connector 351 through the transmission mechanism. The rotary drive member outputs rotational motion, and the transmission mechanism converts the rotational motion output by the rotary drive member into linear motion of the connector 351. The rotary drive member can be an electric motor, an internal combustion engine, etc. The transmission mechanism can be a crank-slider mechanism, a lead screw-nut mechanism, etc.

[0219] The winding mechanism 36 is used to drive the center needle 2213 to rotate. When the winding device 30 is working, the connecting mechanism 35 first connects the first isolator 2214 and the second isolator 2215 to the center needle 2213. Then, the winding mechanism 36 drives the center needle 2213, which is connected to the first isolator 2214 and the second isolator 2215, to rotate, thereby causing the first electrode 2211, the first isolator 2214, the second electrode 2212, and the second isolator 2215 to be wound around the outer periphery of the center needle 2213. In some embodiments, the winding mechanism 36 includes a winding needle that can cooperate with the center needle 2213 to drive the center needle 2213 to rotate, thereby causing the first electrode 2211, the first isolator 2214, the second electrode 2212, and the second isolator 2215 to be wound around the outer periphery of the center needle 2213.

[0220] Please refer to Figure 16In some embodiments, the connecting mechanism 35 includes a heating unit 354 for heating the connector 351 so that the connector 351 heats and fuses the first substrate 22141 and the center pin 2213 through the first connecting portion 25.

[0221] The heating unit 354 is a structure in the connecting mechanism 35 used to heat the connector 351. The heating unit 354 can be connected to the connector 351 to conduct heat to the connector 351. The heating unit 354 can also be spaced apart from the connector 351 to radiate heat to the connector 351. In some embodiments, the heating unit 354 includes a heating wire. In other embodiments, the heating unit includes an infrared heating element.

[0222] By setting up a heating unit 354, the heating unit 354 can heat the connector 351, thereby realizing the heat fusion connection between the first substrate 22141 and the center pin 2213, which is simple, convenient and has a low manufacturing cost.

[0223] In some embodiments, the connector 351 is detachably connected to the heating unit 354.

[0224] "Detachable connection" refers to a connection method in which the connector and the connected parts remain undamaged and maintain their original connection performance even after multiple disassembly and assembly. For example, connector 351 and heating unit 354 can be detachably connected through structures such as quick-release screws, spring clips, pin positioning, magnetic fixing, slider locking, rotating clips, and dovetail grooves.

[0225] By making the connector 351 and the heating unit 354 detachably connected, it is easy to replace the connector 351 when it is damaged, which helps to reduce maintenance costs.

[0226] Please refer to Figure 15 In some embodiments, the connector 351 includes a body portion having a pressing surface 3511, a tooth 352 disposed on the pressing surface 3511, and the tooth 352 and / or the pressing surface 3511 being provided with an anti-stick coating.

[0227] The main body is the core structure of the connector 351. The main body has a pressing surface 3511, which can be a flat surface or a curved surface. Please refer to [reference needed]. Figure 15 In the embodiment shown in the figure, the pressing surface 3511 is an arc surface to match the outer peripheral surface of the center pin 2213, thereby improving the pressing effect.

[0228] The protruding teeth 352 are provided on the pressing surface 3511 so that when the pressing surface 3511 presses the first isolation member 2214 onto the center needle 2213, the protruding teeth 352 can pierce the first coating 22142, thereby exposing the first substrate 22141 of the first isolation member 2214, which facilitates the connection between the first substrate 22141 and the center needle 2213.

[0229] The tooth 352 may have an anti-stick coating, while the pressing surface 3511 may not have an anti-stick coating; or the pressing surface 3511 may have an anti-stick coating, while the tooth 352 may not have an anti-stick coating; or both the tooth 352 and the pressing surface 3511 may have an anti-stick coating.

[0230] The anti-stick coating can be a ceramic coating, a silicon carbide coating, etc.

[0231] By providing an anti-stick coating on the protruding teeth 352 and the pressing surface 3511, it is beneficial to reduce the risk of adhesion to the first separator 2214, reduce the risk of damaging the first separator 2214, and improve the winding quality.

[0232] It should be noted that the winding device 30 provided in this application embodiment is applicable not only to composite separator films with coatings, but also to single-layer separator films without coatings.

[0233] According to some embodiments of this application, please refer to Figures 3-11 .

[0234] This application provides a battery cell 20, which includes an electrode assembly 22 and a first connecting portion 25. The electrode assembly 22 includes a first electrode 2211, a second electrode 2212, a center pin 2213, and a first separator 2214. The first electrode 2211 and the second electrode 2212 have opposite polarities. The first electrode 2211, the first separator 2214, and the second electrode 2212 are all wound around the outer periphery of the center pin 2213. The first separator 2214 includes a first substrate 22141 and a first coating 22142. The first coating 22142 is disposed on the surface of the first substrate 22141 facing the center pin 2213. The first connecting portion 25 is connected to the first substrate 22141 and passes through the first coating 22142 to connect to the center pin 2213. By winding the first electrode 2211, the first separator 2214, and the second electrode 2212 around the outer periphery of the center pin 2213, the center pin 2213 can support the first electrode 2211, the first separator 2214, and the second electrode 2212, thereby reducing the risk of inner ring collapse of the electrode assembly 22 and improving the reliability of the battery cell 20. By providing a first connecting portion 25 and connecting the first connecting portion 25 through the first coating 22142 to the center pin 2213, the connection between the first substrate 22141 and the center pin 2213 is achieved, which helps to improve the connection strength between the first separator 2214 and the center pin 2213. In this way, during the winding process, the first separator 2214 is not easy to detach from the center pin 2213, and the first electrode 2211, the second electrode 2212 and the first separator 2214 can be firmly wound on the center pin 2213 under tension. This helps to reduce the risk of slippage of the first electrode 2211, the second electrode 2212 and the first separator 2214, which helps to reduce the risk of lithium plating and improve the reliability of the battery cell 20.

[0235] The first separator 2214 includes a second coating 22143, which is disposed on the surface of the first substrate 22141 opposite to the center pin 2213. The second coating 22143 has a first surface 221431 opposite to the first substrate 22141. A first recess 22144 is provided at a position corresponding to the first connecting portion 25. The first recess 22144 is recessed from the first surface 221431 toward the center pin 2213, and a portion of the first recess 22144 is located within the first substrate 22141. By providing a first recess 22144 and recessing it from the first surface 221431 toward the center pin 2213, with a portion of the first recess 22144 located within the first substrate 22141, energy can be directly applied to the first substrate 22141 from the first recess 22144 during manufacturing, and is less likely to be blocked and dispersed by the second coating 22143. This allows the first substrate 22141 and the center pin 2213 to connect to form the first connecting portion 25, which is beneficial for improving connection efficiency and connection quality.

[0236] The electrode assembly 22 further includes a second separator 2215, which is located on the side of the first separator 2214 opposite to the center pin 2213. The first electrode 2211, the first separator 2214, the second electrode 2212, and the second separator 2215 are all wound around the outer periphery of the center pin 2213. The second separator 2215 includes a second substrate 22151 and a third coating 22152, which is disposed on the surface of the second substrate 22151 facing the center pin 2213. The battery cell 20 includes a second connecting portion 26, which is connected to the surface of the second substrate 22151 facing the center pin 2213 and passes through the third coating 22152 to connect to the first substrate 22141. By providing a second isolator 2215, which cooperates with the first isolator 2214, the first electrode 2211 and the second electrode 2212 are insulated and isolated, reducing the risk of short circuit due to contact between the first electrode 2211 and the second electrode 2212. By providing a second connecting portion 26 to connect the second substrate 22151 and the first substrate 22141, the connection strength between the second isolator 2215 and the first isolator 2214 is enhanced, reducing the risk of the second isolator 2215 detaching from the first isolator 2214 during winding, which is beneficial to improving winding quality.

[0237] The first separator 2214 includes a second coating 22143, which is disposed on the surface of the first substrate 22141 opposite to the center pin 2213. A second connecting portion 26 passes through the third coating 22152 and the second coating 22143 and connects to the first substrate 22141. By providing the second coating 22143 and the third coating 22152, the mechanical strength and puncture resistance of the first separator 2214 and the second separator 2215 are improved, as are their thermal stability, electrolyte wettability, and retention capacity. By allowing the second connecting portion 26 to pass through the third coating 22152 and the second coating 22143 and connect to the first substrate 22141, the connection strength between the second separator 2215 and the first separator 2214 is enhanced, reducing the risk of the second separator 2215 detaching from the first separator 2214 during winding, thus improving winding quality.

[0238] A first recess 22144 is provided at a position corresponding to the first connecting portion 25 in the first spacer 2214, and a portion of the first recess 22144 is located within the first substrate 22141. A through hole 22154 is provided at a position corresponding to the first recess 22144 in the second spacer 2215, and the through hole 22154 penetrates the second substrate 22151 and the second connecting portion 26, and the through hole 22154 and the first recess 22144 are connected. By providing the through hole 22154 at the position corresponding to the first recess 22144 in the second spacer 2215, and the first recess 22144 at the position corresponding to the first connecting portion 25 in the first spacer 2214, energy can be directly applied to the first substrate 22141 from the first recess 22144 during manufacturing, and is less likely to be blocked and dispersed by the second coating 22143 and the third coating 22152, so that the first substrate 22141 and the center pin 2213 are connected to form the first connecting portion 25, which is beneficial to improving connection efficiency and connection quality. In addition, energy can be directly applied to the first substrate 22141 and the second substrate 22151 from the through hole 22154 and the first recess 22144, and is not easily blocked or dispersed by the third coating 22152, so that the first substrate 22141 and the second substrate 22151 are connected to form the second connection part 26, which is beneficial to improving the connection efficiency and connection quality.

[0239] The second isolator 2215 includes a fourth coating 22153, which is disposed on the surface of the second substrate 22151 opposite to the central pin 2213. A through hole 22154 penetrates the fourth coating 22153, the second substrate 22151, and the second connecting portion 26. By providing the fourth coating 22153, the mechanical strength and puncture resistance of the second isolator 2215 can be improved, thermal stability can be improved, and electrolyte wettability and retention can be enhanced. By allowing the through hole 22154 to penetrate the fourth coating 22153, the second substrate 22151, and the second connecting portion 26, energy can be directly applied to the first substrate 22141 and the second substrate 22151 from the through hole 22154 and the first recess 22144, and is less likely to be blocked and dispersed by the third coating 22152 and the fourth coating 22153. This allows the first substrate 22141 and the second substrate 22151 to connect to form the second connecting portion 26, which is beneficial to improving connection efficiency and connection quality.

[0240] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized in that, include: An electrode assembly includes a first electrode, a second electrode, a center pin, and a first separator. The first electrode and the second electrode have opposite polarities. The first electrode, the first separator, and the second electrode are all wound around the outer periphery of the center pin. The first separator includes a first substrate, a first coating, and a second coating. The first coating is disposed on the surface of the first substrate facing the center pin, and the second coating is disposed on the surface of the first substrate facing away from the center pin. The second coating has a first surface facing away from the first substrate. The first connecting part is connected to the first substrate. The first connecting part passes through the first coating and is connected to the center pin. The first connecting part is a connecting column formed by hot-melt connection or welding connection of the first substrate and the center pin. The first isolation member is provided with a first recess at a position corresponding to the first connecting part. The first recess is recessed from the first surface toward the center pin. A part of the first recess is located in the first substrate.

2. The battery cell according to claim 1, characterized in that, The depth of the first recess is less than the sum of the thickness of the first substrate and the thickness of the second coating.

3. The battery cell according to claim 1, characterized in that, The first recess extends into the first connecting portion.

4. The battery cell according to claim 3, characterized in that, The first connecting portion includes a first part and a second part connected together, the first coating surrounds the first part, the second part is embedded in the central pin, and the first recess extends into the first part and is at a distance from the second part.

5. The battery cell according to claim 3, characterized in that, The first connecting portion includes a first part and a second part connected together, the first coating surrounds the first part, the second part is embedded in the central pin, and the first recess extends into the second part.

6. The battery cell according to claim 1, characterized in that, The first recess is columnar.

7. The battery cell according to claim 1, characterized in that, The first recess is a cone-shaped portion whose diameter gradually decreases along the direction from the first surface toward the central needle.

8. The battery cell according to claim 1, characterized in that, The first recess includes a first segment and a second segment. One end of the first segment extends to the first surface, and the other end of the first segment is connected to the second segment. The first segment is columnar, and the second segment is conical with a diameter that gradually decreases along the direction from the first surface toward the central needle.

9. The battery cell according to claim 1, characterized in that, A portion of the first connecting part is embedded in the central pin.

10. The battery cell according to any one of claims 1-9, characterized in that, The electrode assembly further includes a second isolator located on the side of the first isolator away from the center needle. The first electrode, the first isolator, the second electrode, and the second isolator are all wound around the outer periphery of the center needle. The second isolator includes a second substrate and a third coating. The third coating is disposed on the surface of the second substrate facing the center needle. The battery cell includes a second connecting portion, which is connected to the surface of the second substrate facing the center pin and passes through the third coating to connect with the first substrate.

11. The battery cell according to claim 10, characterized in that, The first isolation member includes a second coating disposed on the surface of the first substrate opposite to the center pin, and the second connecting portion passes through the third coating and the second coating and is connected to the first substrate.

12. The battery cell according to claim 11, characterized in that, The first isolation member has a first recess at a position corresponding to the first connecting portion, and a portion of the first recess is located within the first substrate. The second isolation member has a through hole at a position corresponding to the first recess. The through hole penetrates the second substrate and the second connecting portion, and the through hole communicates with the first recess.

13. The battery cell according to claim 12, characterized in that, The second isolation member includes a fourth coating, which is disposed on the surface of the second substrate opposite to the center pin, and the through hole penetrates the fourth coating, the second substrate, and the second connecting portion.

14. The battery cell according to any one of claims 1-9, characterized in that, The first isolator includes at least one row of first connecting portions, each row of first connecting portions including a plurality of first connecting portions, the plurality of first connecting portions being spaced apart along the extension direction of the winding axis of the electrode assembly.

15. The battery cell according to claim 14, characterized in that, The first isolation member includes multiple rows of the first connecting portions, which are spaced apart along the winding direction of the first isolation member.

16. A battery device, characterized in that, Includes the battery cell according to any one of claims 1-15.

17. An electrical device, characterized in that, Includes a battery cell according to any one of claims 1-15, the battery cell being used to provide electrical energy to the electrical device.

18. A winding device, characterized in that, include: The first supplier, used to provide the first electrode; A second providing mechanism is used to provide a second electrode plate, the second electrode plate having the opposite polarity to the first electrode plate; A third providing mechanism is used to provide a first isolation member, the first isolation member including a first substrate and a first coating, the first coating being disposed on the surface of the first substrate; The fourth providing agency is used to provide the central needle; A connecting mechanism includes a connector having a plurality of teeth, the connector being used to connect the first substrate and the central pin after the teeth pierce the first substrate and the first coating to form a first connecting portion, the first connecting portion passing through the first coating; A winding mechanism is used to drive the center needle to rotate so that the first electrode, the first separator and the second electrode are wound around the outer periphery of the center needle; The first coating is applied to the surface of the first substrate facing the center pin. The connecting mechanism includes a heating unit for heating the connector so that the connector heats the first substrate and the center pin together through the first connecting portion.

19. The winding apparatus according to claim 18, characterized in that, The connector is detachably connected to the heating unit.

20. The winding apparatus according to claim 18, characterized in that, The connector includes a body portion, the body portion having a pressing surface, the protruding teeth being disposed on the pressing surface, and the protruding teeth and / or the pressing surface being provided with an anti-stick coating.

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