Battery cell, battery, and electric device

Abstract

The application relates to a battery monomer, a battery and a power utilization device. The battery monomer comprises a battery core and a first insulation piece, and the first insulation piece wraps the battery core; the first insulation piece has an inner side surface facing the battery core and an outer side surface facing away from the battery core, and a first through hole is arranged on the first insulation piece; the first through hole penetrates the inner side surface and the outer side surface, and the cross-sectional area of the first through hole on the inner side surface is smaller than that on the outer side surface; or the first through hole is configured to comprise a plurality of first through holes, and each first through hole penetrates the inner side surface and the outer side surface. The battery monomer of the application can increase the electrolyte flow area, make the electrolyte flow better, is beneficial to electrolyte infiltration, can block the battery core falling objects or other foreign matters, improve the metal chip falling or carbon powder falling situation, improve the safety and prolong the service life.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to battery cells, batteries and electrical devices. Background Technology

[0002] With the increasing demand for longer driving range in new energy vehicles, higher requirements are being placed on the wetting rate of the electrolyte in power batteries. In related technologies, insulating sheets are typically used to cover the outer surface of the bare cells in power batteries, preventing direct contact between the casing and the bare cells, thereby improving the safety performance of the power battery. Simultaneously, multiple through-holes are created in the insulating sheet to allow the electrolyte to permeate the bare cells, thus increasing the electrolyte wetting rate. However, there is a risk of metal shavings or carbon powder falling from the bare cells, which can easily cause internal corrosion of the cells. Summary of the Invention

[0003] In view of the above problems, this application provides a battery cell, a battery and an electrical device that can improve the wetting effect after electrolyte injection and reduce the risk of metal shavings or carbon powder falling off.

[0004] In a first aspect, this application provides a battery cell, which includes a battery cell and a first insulating member, the first insulating member enclosing the battery cell; the first insulating member has an inner side facing the battery cell and an outer side facing away from the battery cell, and the first insulating member is provided with a first through hole; wherein, the first through hole penetrates the inner side and the outer side, and the cross-sectional area of ​​the first through hole on the inner side is smaller than the cross-sectional area of ​​the first through hole on the outer side; or, the first through hole is constructed to include a plurality of first through holes, each of which penetrates the inner side and the outer side.

[0005] In the technical solution of this application embodiment, the battery cell is insulated and protected by a first insulating component, and a first through hole is provided on the first insulating component. The first through hole is constructed as an integral through hole or a mesh hole including multiple first through holes. The cross-sectional area of ​​the integral through hole on the inner side of the first insulating component is smaller than the cross-sectional area on the outer side of the first insulating component. This can increase the electrolyte flow area, making the electrolyte flow better and improving the wetting effect after electrolyte injection. At the same time, it can block the battery cell from falling off or other foreign objects, reduce the passage of metal shavings through the first insulating component, improve the situation of metal shavings or carbon powder falling off, reduce the internal corrosion of battery cells, and reduce the safety risk of short circuit. Thus, it can improve the electrolyte wetting effect while reducing the risk of metal shavings or carbon powder falling off, improve safety and extend service life, and meet the requirements of higher driving range.

[0006] In some embodiments, the diameter of the first through hole increases from the inside to the outside of the first insulating member. Thus, the flow area of ​​the first through hole decreases from the side of the first insulating member away from the battery cell to the side closer to the battery cell, forming a constricting electrolyte flow channel. This improves electrolyte flow and facilitates the electrolyte flowing into the inside of the first insulating member through the first through hole, allowing the electrolyte to effectively wet the electrodes of the battery cell, thereby enhancing the wetting effect of the electrolyte.

[0007] In some embodiments, the diameter of the first through hole on the inner side is less than or equal to 0.2 mm. This helps reduce the risk of metal shavings or carbon powder falling off, improves insulation protection, reduces internal corrosion of battery cells, and improves electrolyte fluid flow and wetting effect.

[0008] In some embodiments, the diameter of the first through-hole on the outer surface is greater than 0.3 mm and less than 1.5 mm. This allows for better electrolyte flow, which improves the electrolyte wetting effect without increasing the risk of metal shavings or carbon powder falling off, thus enhancing safety and extending service life.

[0009] In some embodiments, the cross-sectional area of ​​the first through hole on the inner surface is S1, and the cross-sectional area of ​​the first through hole on the outer surface is S2, wherein 0.3 ≤ S1 / S2 ≤ 0.7. This approach balances the molding process and improves electrolyte wetting rate while reducing the risk of metal chip shedding, thus helping to lower costs.

[0010] In some embodiments, the diameter of the first through hole is less than or equal to 0.2 mm. This helps to further reduce the risk of metal shavings or carbon powder falling off, improve the insulation protection effect, reduce internal corrosion of battery cells, and at the same time improve the fluidity of the electrolyte and improve the wetting effect of the electrolyte.

[0011] In some embodiments, the first insulating member further comprises a plurality of crease structures; wherein at least one crease structure has a plurality of first through holes arranged along the crease forming direction. This allows the processing of the crease structures to be combined with the forming process of the first through holes, eliminating the need for additional openings, simplifying the process, reducing costs, and facilitating electrolyte flow into the gap between the battery cell and the first insulating member, thereby improving electrolyte injection efficiency and further enhancing the wetting effect after electrolyte injection.

[0012] In some embodiments, the first insulating member includes a large surface area, a side surface area, and a bottom surface area; wherein at least one of the large surface area, the side surface area, and the bottom surface area is provided with a plurality of first through holes. This further increases the electrolyte flow area, improves electrolyte fluidity, and facilitates the electrolyte's penetration through the first insulating member into the large surface, side surface, and bottom surface of the battery cell, further improving the wetting effect after electrolyte injection and helping to meet higher driving range requirements.

[0013] In some embodiments, the spacing between any two adjacent first through holes is the same; or, on at least one of the large surface area, the side surface area, and the bottom surface area, the spacing between two adjacent first through holes closer to its geometric center is smaller than the spacing between two adjacent first through holes farther from its geometric center.

[0014] The even distribution of multiple first through holes allows the electrolyte to flow uniformly into the inner side of the first insulating component, and the process is simple and convenient. Having more first through holes near the geometric center of at least one of the three areas—the large surface area, the side surface area, and the bottom surface area—allows more electrolyte to permeate through the first insulating component and reach at least one of the three centers of the large surface area, the side surface area, and the bottom surface of the battery cell. This enhances the wetting effect of the electrolyte by strengthening the wetting of the center positions of the large surface area, the side surface area, and the bottom surface of the battery cell.

[0015] In some embodiments, a plurality of first through holes are distributed in the central region of at least one of the large surface area, the side surface area, and the bottom surface area. This facilitates better wetting of at least one of the three centers of the large surface area, the side surface area, and the bottom surface area of ​​the battery cell, thereby improving the electrolyte wetting effect.

[0016] In some embodiments, the battery cell further includes a second insulating member, which is stacked on the outer side of the bottom surface region of the first insulating member. The second insulating member has multiple second through holes connecting its inner and outer sides, and these second through holes correspond one-to-one with multiple first through holes in the bottom surface region. Thus, the first and second insulating members work together to facilitate effective electrolyte wetting of the cell's electrodes from the bottom, further improving the wetting effect after electrolyte injection, increasing injection efficiency, and enhancing the wettability of the cell's electrodes, which is beneficial for meeting higher driving range requirements.

[0017] In some embodiments, the second insulating member has a first side facing the first insulating member and a second side facing away from the first insulating member; wherein the second through hole penetrates the first side and the second side; or, the second through hole is constructed to include a plurality of second through holes, each of which penetrates both the first and second sides. Thus, the mesh-like second through hole increases the opening area, allowing for better electrolyte flow and facilitating electrolyte wetting. This improves the wetting effect after electrolyte injection. Simultaneously, the smaller opening area of ​​a single second through hole reduces the risk of metal shavings or carbon powder falling off, minimizing internal corrosion of the battery cell and reducing the safety risk of short circuits between the cell and the casing.

[0018] In some embodiments, the cross-sectional area of ​​the second through hole on the first side is smaller than the cross-sectional area of ​​the second through hole on the second side. Thus, the opening area of ​​the second insulating member on the side away from the first insulating member is larger, increasing the electrolyte flow area and allowing more electrolyte to flow towards the first insulating member. This improves electrolyte fluidity and facilitates wetting, resulting in a better wetting effect. Simultaneously, the opening area of ​​the second insulating member on the side closer to the first insulating member is smaller, which can improve the situation of metal shavings falling off and reduce the risk of metal shavings falling off.

[0019] In some embodiments, the diameter of the second through hole on the first side is larger than the diameter of the first through hole on the outer side. This further increases the electrolyte flow area, allowing more electrolyte to flow through the second through hole to the first through hole in the first insulating member, thereby wetting the battery cell and improving the electrolyte wetting effect.

[0020] Secondly, this application provides a battery, which includes the battery cell in any of the above embodiments.

[0021] Thirdly, this application provides an electrical device, which includes the battery in the above embodiments or a battery cell in any of the above embodiments, and the battery and battery cell are used to provide electrical energy.

[0022] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0023] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0024] Figure 1 This is a schematic diagram of the structure of a vehicle according to some embodiments of this application.

[0025] Figure 2 This is an exploded structural diagram of a battery according to some embodiments of this application.

[0026] Figure 3 This is an exploded structural diagram of a battery cell according to some embodiments of this application.

[0027] Figure 4 This is a three-dimensional structural diagram of the folded state of the first insulating member in some embodiments of this application.

[0028] Figure 5 for Figure 4 A magnified structural diagram of point A in the middle.

[0029] Figure 6 This is a schematic diagram of the unfolded state of the first insulating member in some embodiments of this application.

[0030] Figure 7 for Figure 6 A magnified structural diagram at point B in the middle.

[0031] Figure 8 This is a partial cross-sectional view of a first insulating element according to some embodiments of this application.

[0032] Figure 9 This is a schematic diagram of the unfolded state of the first insulating member in some other embodiments of this application.

[0033] Figure 10 for Figure 9 A magnified structural diagram at point C.

[0034] Figure 11 This is a schematic diagram of the unfolded state of the first insulating member according to some embodiments of this application.

[0035] Figure 12 This is a bottom view of the folded state of the first insulating member in some embodiments of this application.

[0036] Figure 13 This is a bottom view of the folded state of the first insulating member in some other embodiments of this application.

[0037] Figure 14 This is an exploded structural diagram showing the cooperation between the first insulating member and the second insulating member in some embodiments of this application.

[0038] Figure 15 This is a bottom view showing the mating of a first insulating member and a second insulating member in some embodiments of this application.

[0039] Figure 16 for Figure 15 A sectional view of the EE section.

[0040] Figure 17 for Figure 16 A magnified structural diagram at point F in the middle.

[0041] The reference numerals in the detailed embodiments are as follows:

[0042] 1000, vehicle; 100, battery; 200, controller; 300, motor;

[0043] 10. Box body; 11. First part; 12. Second part;

[0044] 20. Battery cell; 21. End cap; 21a. Electrode terminal; 22. Housing; 23. Cell; 23a. Tab; 24. Adapter piece; 25. First insulating component; 251. First through hole; 2511. First through hole; 252. Inner side surface; 253. Outer side surface; 254. Crease structure; 255. Large surface area; 256. Side surface area; 257. Bottom surface area; 26. Second insulating component; 261. Second through hole; 262. First side surface; 263. Second side surface. Detailed Implementation

[0045] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0046] In this document, the term "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 throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein 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 specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0048] In the description of the embodiments of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0049] In the description of the embodiments of this application, the terms "first" and "second" are used for descriptive purposes only to distinguish different objects, and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary or secondary relationship of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of the embodiments of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] In the description of the embodiments 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, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0051] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0052] In the description of the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0053] It should be noted that an element is referred to as being "fixed to" or "set on" another element, which may be directly on the other element or may also include an intervening element. An element is considered to be "connected" to another element, which may be directly connected to the other element or may also include an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0054] Currently, judging from market trends, the application of power batteries is becoming increasingly widespread. Power batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. As a crucial component of new energy vehicles, the increasing demand for longer driving ranges in these vehicles places higher demands on the electrolyte wetting rate in power batteries.

[0055] In related technologies, power batteries typically use insulating sheets to wrap bare cells, with a base plate below the insulating sheet, and an aluminum casing below that. The insulating sheet and the base plate are heat-fused together, and the base plate lies flat on the bottom of the aluminum casing, preventing direct contact between the aluminum casing and the bare cells. This prevents short circuits caused by contact between the bare cells and the aluminum casing, thus providing insulation and protection for the bare cells and improving the safety performance of the power battery. An explosion-proof valve is located at the bottom of the aluminum casing. The insulating sheet and the base plate usually have two positioning holes, which are covered with adhesive tape. Because the insulating sheet and the base plate only have two holes, and these holes are located at opposite ends of the bare cells, the electrolyte wetting is insufficient, which can easily lead to voltage drops during later battery use.

[0056] To improve the electrolyte wetting rate, multiple through holes can be made in the insulating sheet and the base plate to allow the electrolyte to wet the bare battery cell. However, if the opening area of ​​the insulating sheet is too large, debris or other foreign objects from the bare battery cell can easily pass through the holes or gaps in the insulating sheet and the base plate, posing a risk of metal shavings or carbon powder falling from the bare battery cell, which can easily cause internal corrosion of the battery cell.

[0057] Based on the above considerations, in order to improve the wetting effect after electrolyte injection and reduce the risk of metal shavings or toner falling off, multiple through holes can be made on the battery cell insulation sheet. The cross-sectional area of ​​the through hole on the side closer to the bare battery cell is smaller than the cross-sectional area on the side away from the bare battery cell. The cross-sectional area on the side away from the bare battery cell is larger, which improves the wetting effect. At the same time, the cross-sectional area on the side closer to the bare battery cell is smaller, which improves the situation of metal shavings and toner falling off and reduces the risk of metal shavings or toner falling off.

[0058] The battery cells disclosed in this application can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. A power system for such an electrical device can be constructed using battery cells and batteries disclosed in this application. This helps reduce costs, meet longer driving range requirements, improve safety, and extend service life.

[0059] This application provides an electrical device that uses a battery as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0060] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to some embodiments of this application.

[0061] 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. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery 100 is disposed inside the vehicle 1000, and the battery 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery 100 can be used to power the vehicle 1000; for example, the battery 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during startup, navigation, and driving.

[0062] In some embodiments of this application, the battery 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.

[0063] Please refer to Figure 2, Figure 2 This is an exploded view of a battery 100 provided in some embodiments of this application. The battery 100 includes a housing 10 and a battery cell 20, with the battery cell 20 housed within the housing 10. The housing 10 provides a space for the battery cell 20 and can have various structures. In some embodiments, the housing 10 may include a first portion 11 and a second portion 12, which overlap each other, jointly defining a space for accommodating the battery cell 20. The second portion 12 may be a hollow structure with one open end, and the first portion 11 may be a plate-like structure, covering the open side of the second portion 12 so that the first portion 11 and the second portion 12 jointly define the space; alternatively, the first portion 11 and the second portion 12 may both be hollow structures with one open side, with the open side of the first portion 11 covering the open side of the second portion 12. Of course, the housing 10 formed by the first portion 11 and the second portion 12 can have various shapes, such as a cylinder, a cuboid, etc.

[0064] In battery 100, a battery cell 20 refers to the smallest unit that makes up battery 100. There can be multiple battery cells 20, which can be connected in series, parallel, or in a mixed manner. A mixed connection means that multiple battery cells 20 are connected in both series and parallel. Multiple battery cells 20 can be directly connected in series, parallel, or in a mixed manner, and then the whole assembly of multiple battery cells 20 is housed in housing 10. Of course, battery 100 can also be formed by first connecting multiple battery cells 20 in series, parallel, or in a mixed manner to form a battery module, and then connecting multiple battery modules in series, parallel, or in a mixed manner to form a whole, which is also housed in housing 10. Battery 100 may also include other structures. For example, battery 100 may also include a busbar component for realizing the electrical connection between multiple battery cells 20.

[0065] Each battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited to these. The battery cell 20 can be cylindrical, flat, cuboid, or other shapes, that is, the battery cell 20 is not limited to a prismatic battery, but can also be a cylindrical battery, etc.

[0066] According to some embodiments of this application, refer to Figure 3 , Figure 3 An exploded view of the battery cell 20 in some embodiments of this application is shown. This application provides a battery cell 20, which includes a cell 23 and a first insulating member 25, the first insulating member 25 enclosing the cell 23.

[0067] like Figure 3As shown, the battery cell 20 typically also includes an end cap 21 and a housing 22. The end cap 21 is sealed at the opening of the housing 22, and the battery cell 23 and the first insulating member 25 are encapsulated within the housing 22. The end cap 21 is a component that closes onto the opening of the housing 22 to isolate the internal environment of the battery cell 20 from the external environment. The shape of the end cap 21 can be adapted to the shape of the housing 22 to fit the housing 22. Optionally, the end cap 21 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 21 is less prone to deformation under pressure and impact, enabling the battery cell 20 to have higher structural strength and improved safety performance. Functional components such as electrode terminals 21a can be provided on the end cap 21. The electrode terminals 21a can be used for electrical connection with the battery cell 23 to output or input electrical energy to the battery cell 20. In some embodiments, the end cap 21 can also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The end cap 21 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this. In some embodiments, an insulating element can also be provided on the inner side of the end cap 21. The insulating element can be used to isolate the electrical connection components in the housing 22 from the end cap 21 to reduce the risk of short circuit. For example, the insulating element can be plastic, rubber, etc.

[0068] The housing 22 is a component used to cooperate with the end cap 21 to form the internal environment of the battery cell 20. This internal environment can accommodate the battery cell 23, the first insulating element 25, the electrolyte, and other functional components. The housing 22 and the end cap 21 can be independent components. An opening can be provided on the housing 22, and the end cap 21 can be used to close the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 21 and the housing 22 can be integrated. Specifically, the end cap 21 and the housing 22 can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 22, the end cap 21 closes the housing 22. The housing 22 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 22 can be determined according to the specific shape and size of the battery cell 23. The material of the housing 22 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. This embodiment does not impose any special limitations on this.

[0069] The battery cell 23 is the component in the battery cell 20 where the electrochemical reaction occurs. The casing 22 may contain one or more battery cells 23. The battery cell 23 is mainly formed by winding or stacking positive and negative electrode plates, and typically a separator is provided between the positive and negative electrode plates. The portions of the positive and negative electrode plates containing active material constitute the main body of the battery cell 23, while the portions of the positive and negative electrode plates without active material each constitute a tab 23a. The positive and negative tabs may be located together at one end of the main body or separately at both ends of the main body. During the charging and discharging process of the battery, the positive and negative active materials react with the electrolyte, and the tabs 23a are connected to the electrode terminals 21a via adapter plates 24 to form a current loop.

[0070] The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector. The positive current collector without the positive active material layer protrudes from the positive current collector with the positive active material layer, and the positive current collector without the positive active material layer constitutes the positive electrode tab. Taking a lithium-ion battery as an example, the positive current collector can be aluminum foil, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. After stirring and mixing the positive active material, a positive electrode slurry is obtained. Then, the positive electrode slurry is coated on the surface of the positive current collector, baked and dried, and then processed through cold pressing (rolling), pre-slitting, slitting, etc., to prepare the positive electrode sheet. The negative electrode sheet includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative current collector. The negative current collector without the negative active material layer protrudes from the negative current collector with the negative active material layer, and the negative current collector without the negative active material layer constitutes the negative electrode tab. The negative electrode current collector can be copper foil, and the negative electrode active material can be carbon or silicon, etc. After stirring and mixing the negative electrode active material, a negative electrode slurry is obtained. This slurry is then coated onto the surface of the negative electrode current collector, baked and dried, and then subjected to cold pressing, pre-slitting, and slitting processes to prepare the negative electrode sheet. The separator can be at least one of glass fiber cloth, non-woven fabric, polypropylene (PP) film, and polyethylene (PE) film; the separator can be a single-layer film or a multi-layer composite film, without limitation.

[0071] Further reference Figures 4 to 10 , Figure 4 This paper shows a three-dimensional structural diagram of the folded state of the first insulating member in some embodiments of this application. Figure 5 It shows Figure 4 Enlarged structural diagram at point A in the middle. Figure 6 This paper shows a schematic diagram of the unfolded state structure of the first insulating member in some embodiments of this application. Figure 7 It shows Figure 6 Enlarged structural diagram at point B. Figure 8A partial cross-sectional view of the first insulating member in some embodiments of this application is shown. Figure 9 This invention provides schematic diagrams of the unfolded state of the first insulating member in other embodiments of this application. Figure 10 It shows Figure 9 A magnified structural diagram at point C.

[0072] The first insulating member 25 has an inner side 252 facing the battery cell 23 and an outer side 253 facing away from the battery cell 23. The first insulating member 25 is provided with a first through hole 251. The first through hole 251 penetrates the inner side 252 and the outer side 253. The cross-sectional area of ​​the first through hole 251 on the inner side 252 is smaller than the cross-sectional area of ​​the first through hole 251 on the outer side 253. Alternatively, the first through hole 251 is constructed to include a plurality of first through holes 2511, each of which penetrates the inner side 252 and the outer side 253.

[0073] The first insulating member 25 encloses the battery cell 23, which can space the housing 22 and the battery cell 23 to achieve insulation protection for the battery cell 23; in some embodiments, the first insulating member 25 has an unfolded state and a folded state, such as Figure 6 and Figure 9 As shown, in the unfolded state, the first insulating member 25 is in the form of a planar sheet; as Figure 3 and Figure 4 As shown, in the folded state, the first insulating member 25 forms a top-opening box with a shape basically the same as that of the housing 22, only slightly smaller in size. For example, if the housing 22 is a cuboid shape, the first insulating member 25, after folding, forms a rectangular box with a top opening adapted to the size of the battery cell 23. The battery cell 23 is first inserted into the folded first insulating member 25, and then inserted into the housing 22 together with the first insulating member 25, thus the first insulating member 25 separates the battery cell 23 from the housing 22. The first insulating member 25 can be made of PP (polypropylene) or PET (polyethylene terephthalate), such as Mylar, a tough polyester polymer with good heat resistance, excellent electrical insulation, and even good electrical performance at high temperatures and high frequencies.

[0074] like Figure 8 As shown, the first insulating member 25 has an inner surface 252 and an outer surface 253 facing away from each other; wherein, the inner surface 252 of the first insulating member 25 refers to the side surface facing the battery cell 23, and the side facing the inner surface 252 of the first insulating member 25 is the inner side of the first insulating member 25; the outer surface 253 of the first insulating member 25 refers to the side surface away from the battery cell 23, and the side facing the outer surface 253 of the first insulating member 25 is the outer side of the first insulating member 25.

[0075] A first through hole 251 is provided on the first insulating member 25, which connects the inner and outer sides of the first insulating member 25, allowing electrolyte to freely pass through the first insulating member 25 and flow into and out of the rectangular box formed by the first insulating member 25. The electrolyte can effectively wet the electrode plates of the cell 23, thereby improving the working efficiency of the battery cell 20 while enhancing the insulation performance of the first insulating member 25. In some embodiments, the number of first through holes 251 on the first insulating member 25 is at least one, such as 1, 2, 4, 6, 8, 10 or more. More first through holes 251 can increase the electrolyte flow area, thereby improving the electrolyte wetting effect.

[0076] In some embodiments, such as Figure 5 , Figure 7 and Figure 8 As shown, the first through hole 251 can be constructed as a through hole that integrally penetrates the inner side 252 and the outer side 253 of the first insulating member 25, and the area of ​​the cross-section of the first through hole 251 on the inner side 252 of the first insulating member 25 is smaller than the area of ​​the cross-section on the outer side 253 of the first insulating member 25; that is, the opening area of ​​the first insulating member 25 facing the battery cell 23 is smaller than the opening area of ​​the side facing away from the battery cell 23, and the diameter of the first through hole 251 inside the first insulating member 25 is smaller than the diameter of the opening outside the first insulating member 25. The cross-sectional shape of the first through hole 251 can be circular, elliptical, rectangular, square, triangular or other irregularly shaped holes, etc., and is not limited here.

[0077] Thus, the first insulating member 25 has a larger opening area on the side away from the cell 23, which increases the electrolyte flow area and allows more electrolyte to flow to the inside of the first insulating member 25. This improves electrolyte flow and facilitates electrolyte wetting, thereby enhancing the wetting effect. At the same time, the first through hole 251 has a smaller cross-sectional area on the side facing the cell 23, which can block debris and other foreign objects from the cell 23. Metal shavings and other debris are less likely to pass through the first insulating member 25, thereby improving the situation of metal shavings falling and reducing the risk of metal shavings or carbon powder falling. This, in turn, reduces the risk of internal corrosion of the battery cell 20 and reduces the safety risk of short circuit between the cell 23 and the casing 22.

[0078] In other embodiments, such as Figure 10As shown, the first through hole 251 can also be constructed as a plurality of first through holes 2511 that respectively penetrate the inner side 252 and the outer side 253 of the first insulating member 25. The cross-sectional area of ​​each first through hole 2511 is smaller than the cross-sectional area of ​​the overall through hole 251 in the previous embodiment located on the inner side 252 of the first insulating member 25. The plurality of first through holes 2511 are arranged in a concentrated manner to form a mesh-like first through hole 251. Thus, the plurality of first through holes 2511 can be arranged according to certain rules to form an electrolyte channel, such as a rectangular array arrangement or a circular array arrangement, etc. However, the size of each first through hole 2511 can effectively block the falling off of the battery cell 23 or other foreign objects. Although the opening area of ​​a single first through hole 2511 is smaller than that of the overall through hole 251, in this embodiment, multiple first through holes 2511 can be formed in a larger area so that the sum of the opening areas of the multiple first through holes 2511 is not less than the opening area of ​​the overall through hole 251. The first through hole 2511 can be a straight through hole with a constant diameter along its axial direction, or the structure of the first through hole 2511 can be similar to that of the overall through hole 251, that is, the cross-sectional area of ​​the first through hole 2511 on the inner side 252 of the first insulating member 25 is smaller than the cross-sectional area of ​​the first through hole 2511 on the outer side 253 of the first insulating member 25. No specific limitation is made here. The shape of the mesh-like first through hole 251 can be one of various shapes such as waist-shaped, triangular, circular, square, etc.

[0079] Thus, the mesh-like first through hole 251 also increases the opening area, increases the electrolyte flow area, makes the electrolyte flow better, and improves the wetting effect after electrolyte injection; at the same time, the opening area of ​​a single first through hole 2511 is smaller, which can block metal shavings and other solid particles, making it difficult for metal shavings to pass through the first insulating component 25, thereby improving the situation of metal shavings falling, reducing the risk of metal shavings or carbon powder falling, reducing the internal corrosion of the battery cell 20, and reducing the safety risk of short circuit between the cell 23 and the casing 22.

[0080] In this embodiment of the application, the battery cell 20 uses a first insulating member 25 to insulate and protect the cell 23. A first through hole 251 is provided on the first insulating member 25. The first through hole 251 is constructed as an integral through hole or a mesh hole including multiple first through holes 2511. The cross-sectional area of ​​the integral through hole 251 on the inner side 252 of the first insulating member 25 is smaller than the cross-sectional area on the outer side 253 of the first insulating member 25. This can increase the electrolyte flow area, making the electrolyte flow better and improving the wetting effect after electrolyte injection. At the same time, it can block the falling off of the cell 23 or other foreign objects, reduce the passage of metal shavings through the first insulating member 25, improve the situation of metal shavings or carbon powder falling off, reduce the internal corrosion of the battery cell 20, and reduce the safety risk of short circuit. Thus, it can improve the electrolyte wetting effect while reducing the risk of metal shavings or carbon powder falling off, improve safety and extend service life, and meet the requirements of higher driving range.

[0081] In some embodiments, refer to Figure 7 The cross-sectional area of ​​the first through hole 251 on the inner side 252 is S1, and the cross-sectional area of ​​the first through hole 251 on the outer side 253 is S2, wherein 0.3≤S1 / S2≤0.7.

[0082] For example, the ratio S1 / S2 can be equal to 0.3, 0.4, 0.5, 0.6, or 0.7, etc. In this embodiment, the first through hole 251 penetrates the inner side 252 and the outer side 253 of the first insulating member 25. The larger the ratio S1 / S2 between the cross-sectional area S1 of the first through hole 251 on the inner side 252 and the cross-sectional area S2 of the first through hole 251 on the outer side 253, the smaller the area difference between S1 and S2, and the worse the effect of improving the electrolyte wetting rate while reducing the risk of metal shavings falling off, but the easier it is to form the first through hole 251; conversely, the smaller the ratio S1 / S2, the larger the area difference between S1 and S2, and the more obvious the effect of improving the electrolyte wetting rate while reducing the risk of metal shavings falling off, but the more difficult it is to form the first through hole 251.

[0083] By setting the ratio S1 / S2 to a range of 0.3-0.7, it is possible to balance the molding process and improve the electrolyte wetting rate while reducing the risk of metal chips falling off, which is beneficial to reducing costs.

[0084] In some embodiments, refer to Figure 8 The diameter of the first through hole 251 increases from the inside to the outside of the first insulating member 25.

[0085] In this embodiment, the first through hole 251 extends through the inner surface 252 and the outer surface 253 of the first insulating member 25. The diameter of the first through hole 251 refers to the size of the first through hole 251 in the direction perpendicular to the axial direction of the first through hole 251. When the first through hole 251 is a circular hole, the diameter of the first through hole 251 is the diameter of the first through hole 251. In some embodiments, the diameter of the first through hole 251 gradually increases from the inner side to the outer side of the first insulating member 25, making the first through hole 251 an overall tapered hole.

[0086] Thus, the flow area of ​​the first through hole 251 decreases from the side of the first insulating member 25 away from the battery cell 23 to the side closer to the battery cell 23, forming a shrinking electrolyte flow channel. This improves electrolyte flow and facilitates the electrolyte flowing into the inner side of the first insulating member 25 through the first through hole 251. The electrolyte can effectively wet the electrode of the battery cell 23, thereby improving the wetting effect of the electrolyte.

[0087] In some embodiments, the diameter D1 of the first through hole 251 on the inner side 252 is less than or equal to 0.2 mm.

[0088] In this embodiment, the first through hole 251 penetrates the inner side 252 and the outer side 253 of the first insulating member 25. The diameter D1 of the first through hole 251 on the side of the first insulating member 25 facing the battery cell 23 is less than or equal to 0.2 mm and greater than 0 mm. For example, D1 can be equal to 0.05 mm, 0.1 mm, 0.15 mm, or 0.2 mm, etc.; in some embodiments, 0.1 mm ≤ D1 ≤ 0.2 mm. The diameter D1 of the first through hole 251 on the inner side 252 refers to the maximum dimension of the outline of the first through hole 251 on the inner side 252 of the first insulating member 25 in the direction perpendicular to the axial direction of the first through hole 251; for example... Figure 7 As shown, when the first through hole 251 is a rectangular hole, the diameter D1 of the first through hole 251 on the inner side 252 is the diagonal length of the rectangular hole; when the first through hole 251 is a circular hole, the diameter D1 of the first through hole 251 on the inner side 252 is the diameter of the circular hole. It can be understood that the smaller the diameter D1 of the first through hole 251 on the inner side 252, the less likely it is for debris and other foreign objects from the battery cell 23 to pass through the first through hole 251 and fall out. The first insulating member 25 will be more effective in blocking debris and other foreign objects from the battery cell 23, thus reducing the risk of metal shavings or carbon powder falling out. However, a small D1 will reduce the fluidity of the electrolyte, hindering electrolyte wetting and reducing the wetting effect.

[0089] By setting the diameter D1 of the first through hole 251 on the inner side 252 to be less than or equal to 0.2 mm, it is beneficial to reduce the risk of metal shavings or carbon powder falling off, improve the insulation protection effect, reduce the internal corrosion of the battery cell 20, and at the same time improve the fluidity of the electrolyte and improve the wetting effect of the electrolyte.

[0090] In some embodiments, the diameter D2 of the first through hole 251 on the outer side 253 is greater than 0.3 mm and less than 1.5 mm.

[0091] In this embodiment, the first through hole 251 penetrates the inner side 252 and the outer side 253 of the first insulating member 25. The diameter D2 of the first through hole 251 on the side of the first insulating member 25 away from the battery cell 23 is greater than 0.3 mm and less than 1.5 mm. For example, D2 can be equal to 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, or 1.4 mm, etc. In some embodiments, 0.5 mm ≤ D2 ≤ 1 mm. Similarly, the diameter D2 of the first through hole 251 on the outer side 253 refers to the maximum dimension of the outline of the first through hole 251 on the outer side 253 of the first insulating member 25 in the direction perpendicular to the axial direction of the first through hole 251. It is understandable that the larger the aperture D2 of the first through hole 251 on the outer side 253, the larger the flow area of ​​the electrolyte, the better the fluidity of the electrolyte, and more electrolyte can flow through the first through hole 251 to the inner side of the first insulating component 25, resulting in a better wetting effect of the electrolyte. However, if D2 is too large, it will increase the risk of metal shavings or carbon powder falling off, which can easily cause internal corrosion of the battery cell 20.

[0092] By setting the diameter D2 of the first through hole 251 on the outer side 253 to be greater than 0.3 mm and less than 1.5 mm, the electrolyte flow is improved, which is beneficial to improving the electrolyte wetting effect. At the same time, it does not increase the risk of metal shavings or carbon powder falling off, thus improving safety and extending service life.

[0093] In some embodiments, refer to Figure 10 The diameter D3 of the first through hole 2511 is less than or equal to 0.2 mm.

[0094] For example, D3 can be equal to 0.05 mm, 0.1 mm, 0.15 mm, or 0.2 mm, etc. The diameter D3 of the first through hole 2511 refers to the maximum dimension of the projected profile of the first through hole 2511 on the inner side 252 or outer side 253 of the first insulating member 25 in the direction perpendicular to the axial direction of the first through hole 2511; for example... Figure 10 As shown, when the projected outline of the first through hole 2511 is rectangular, the hole diameter D3 of the first through hole 2511 is the diagonal length of the rectangular hole; in some embodiments, 0.1 mm ≤ D3 ≤ 0.2 mm.

[0095] By setting the diameter D3 of the first through hole 2511 to be less than or equal to 0.2 mm, it is beneficial to further reduce the risk of metal shavings or carbon powder falling off, improve the insulation protection effect, reduce the internal corrosion of the battery cell 20, and at the same time improve the fluidity of the electrolyte and improve the wetting effect of the electrolyte.

[0096] In some embodiments, refer to Figures 4 to 6 and Figure 9 The first insulating member 25 is also provided with a plurality of crease structures 254; wherein, at least one crease structure 254 is provided with a plurality of first through holes 251 arranged along the crease forming direction.

[0097] Multiple crease structures 254 can be pre-processed on the first insulating member 25. These crease structures 254 are used to form creases. The crease structure 254 can be a scratch line extending along the crease forming direction; for example, the scratch line can be formed by thinning. Alternatively, the crease structure 254 can include multiple through holes arranged sequentially along the crease forming direction. The specific form of the crease structure 254 is not limited. The first insulating member 25 is bent at the crease structure 254, changing from an unfolded state to a folded state, so that the first insulating member 25 can be wrapped around the battery cell 23, insulating the battery cell 23 from the housing 22. By removing material, the location of the crease structure 254 is made easier to bend, thereby reducing the difficulty of changing the first insulating member 25 to a folded state and improving the operability of bending. In some embodiments, the side of the cell 23 structure has rounded corners, and the crease structure 254 at the corresponding position on the first insulating member 25 can be provided with two scratch lines or two rows of through holes so that the first insulating member 25 can better fit with the cell 23, reduce the situation where the metal shell 22 and the first insulating member 25 are scratched due to the presence of sharp corners during subsequent assembly, and reduce the impact on insulation safety.

[0098] Multiple first through holes 251 are distributed on the first insulating member 25. Multiple first through holes 251 can be provided at the location of at least one crease structure 254, and the multiple first through holes 251 are arranged in a row along the crease forming direction, so that the multiple first through holes 251 replace at least part of the through holes of the crease structure 254.

[0099] In this way, the processing of the crease structure 254 can be combined with the forming process of the first through hole 251, without the need for additional openings, which helps to simplify the process and reduce costs. Furthermore, the crease structure 254 is usually located in the corner area of ​​the first insulating member 25 in the folded state, which facilitates the flow of electrolyte into the gap between the battery cell 23 and the first insulating member 25, thereby improving the electrolyte injection efficiency and further improving the wetting effect after electrolyte injection.

[0100] In some embodiments, refer to Figure 4 , Figure 6 and Figure 9 and further refer to Figure 11 and Figure 12 , Figure 11 This paper shows a schematic diagram of the unfolded state of the first insulating member in some embodiments of this application. Figure 12 A bottom view of the folded state of the first insulating member in some embodiments of this application is shown; the first insulating member 25 includes a large surface area 255, a side surface area 256 and a bottom surface area 257; wherein, at least one of the large surface area 255, the side surface area 256 and the bottom surface area 257 is provided with a plurality of first through holes 251.

[0101] The bottom surface area 257 of the first insulating member 25 is used to adhere to the bottom of the battery cell 23. The bottom surface area 257 forms the bottom of the first insulating member 25, and its shape and area are basically consistent with the bottom surface shape and area of ​​the battery cell 23. For example, the large surface area 255 of the first insulating member 25 can be connected to the bottom surface area 257; the large surface area 255 of the first insulating member 25 is used to adhere to the large surface of the battery cell 23 after folding, and its shape and area are basically consistent with the large surface shape and area of ​​the battery cell 23. For example, the side surface area 256 of the first insulating member 25 can be connected to the large surface area 255; the side surface area 256 of the first insulating member 25 is used to adhere to the side of the battery cell 23 adjacent to the large surface after folding, and its shape and area are basically consistent with the side surface shape and area of ​​the battery cell 23. In some embodiments, the first insulating member 25 can be a one-piece structure, and the first insulating member 25 is divided into a large surface area 255, a side surface area 256, and a bottom surface area 257 by a crease structure 254. The first insulating member 25 is wrapped around the battery cell 23 by bending and bonding operations, which can reduce the gap between the edge position of the first insulating member 25 and the battery cell 23 in the folded state, thereby improving the covering effect of the battery cell 23. In this way, the matching degree between the first insulating member 25 and the battery cell 23 can be improved, the bonding area between the first insulating member 25 and the battery cell 23 can be increased, and the structural stability of the first insulating member 25 in the folded state can be improved, thereby improving the covering effect of the battery cell 23, effectively improving the insulation performance of the first insulating member 25, thereby improving safety performance, reducing material waste, and helping to reduce costs.

[0102] It should be noted that "the three areas 255, 256 and 257" refer to the first insulating member 25 having three surface areas, rather than a quantity of three. For example, the battery cell 23 usually has two large surfaces and two side surfaces, and the first insulating member 25 may have two large surface areas 255 and at least two side surface areas 256.

[0103] like Figure 11As shown, the first through-hole 251 can be formed in the large surface area 255 and the side surface area 256. Because there is a gap between the edge of the first insulating member 25 and the periphery of the battery cell 23, the electrolyte will disperse to the surrounding area after injection. Therefore, the electrolyte around the battery cell 23 is more easily wetted, while the large surface and side surface are less easily wetted. By forming the first through-hole 251 in the large surface area 255 and the side surface area 256, the surrounding electrolyte can permeate through the first insulating member 25 and wet the large surface and side surface of the battery cell 23. Figure 12 As shown, the first through hole 251 can also be formed in the bottom area 257 so that the electrolyte at the bottom can wet the bottom surface of the cell 23.

[0104] This can further increase the electrolyte flow area, improve electrolyte fluidity, and facilitate the electrolyte to penetrate the first insulating component 25 and wet the large surface, side surface and bottom surface of the battery cell 23, further improving the wetting effect after electrolyte injection and helping to meet the requirements of higher driving range.

[0105] In some embodiments, refer to Figure 12 The spacing D4 between any two adjacent first through holes 251 is the same.

[0106] The spacing D4 between two adjacent first through holes 251 refers to the distance between the adjacent boundaries of two adjacent first through holes 251. In this way, the multiple first through holes 251 are evenly distributed, which allows the electrolyte to flow evenly into the inner side of the first insulating component 25, and the processing is simple and convenient.

[0107] In other embodiments, reference is made to Figure 13 , Figure 13 A bottom view of the folded state of the first insulating member in some other embodiments of this application is shown; on at least one of the large surface area 255, the side surface area 256 and the bottom surface area 257, the distance D5 between two adjacent first through holes 251 near its geometric center is smaller than the distance D6 between two adjacent first through holes 251 away from its geometric center.

[0108] The arrangement of the plurality of first through holes 251 on the first insulating member 25 in this embodiment can adopt one or more of the following arrangement rules: the distance D5 between two adjacent first through holes 251 near the geometric center of the large surface area 255 is less than the distance D5 between two adjacent first through holes 251 far from the geometric center of the large surface area 255; the distance D5 between two adjacent first through holes 251 near the geometric center of the side surface area 256 is less than the distance D5 between two adjacent first through holes 251 far from the geometric center of the side surface area 256; the distance D5 between two adjacent first through holes 251 near the geometric center of the bottom surface area 257 is less than the distance D5 between two adjacent first through holes 251 far from the geometric center of the bottom surface area 257.

[0109] Because there is a gap between the edge of the first insulating component 25 and the periphery of the battery cell 23, the electrolyte will disperse to the periphery after injection. Therefore, the electrolyte is easier to wet around the periphery of the battery cell 23, while it is not easy to wet the center. Therefore, more first through holes 251 can be set in the areas near the geometric center of the large surface area 255, side surface area 256 and bottom surface area 257 of the first insulating component 25. That is to say, the distribution of the first through holes 251 in the large surface area 255, side surface area 256 and bottom surface area 257 is uneven. The number of first through holes 251 in the large surface area 255, side surface area 256 and bottom surface area 257 near the geometric center is greater than the number of first through holes 251 far from the geometric center. This makes the distance D5 between two adjacent first through holes 251 near the geometric center in the large surface area 255, side surface area 256 and bottom surface area 257 smaller than the distance D6 between two adjacent first through holes 251 far from the geometric center. In some embodiments, the spacing between the plurality of first through holes 251 on the large surface area 255, the side surface area 256 and the bottom surface area 257 gradually increases in a direction away from their respective geometric centers.

[0110] Thus, by providing more first through holes 251 in the area near the geometric center of at least one of the three areas—the large surface area 255, the side surface area 256, and the bottom surface area 257—more electrolyte can permeate through the first insulating member 25 to at least one of the three centers of the large surface, the side surface, and the bottom surface of the cell 23, thereby enhancing the wetting effect of the electrolyte at the center of the large surface, the side surface, and the bottom surface of the cell 23.

[0111] In some embodiments, refer to Figures 11 to 13 Multiple first through holes 251 are distributed in the central region of at least one of the three areas: large surface area 255, side surface area 256, and bottom surface area 257.

[0112] The central area of ​​the large surface area 255, the side surface area 256, and the bottom surface area 257 refers to the portion of the area containing their respective geometric centers. For example, the area of ​​the central area of ​​the large surface area 255, the side surface area 256, and the bottom surface area 257 can be set to 1 / 2 of their respective areas. For example, multiple first through holes 251 are concentrated in the central areas of the large surface area 255, the side surface area 256, and the bottom surface area 257, and are arranged centrally.

[0113] This allows for better wetting of at least one of the three surfaces of the battery cell 23: the center of the large surface, the center of the side surface, and the center of the bottom surface, thereby improving the electrolyte wetting effect.

[0114] In some embodiments, refer to Figure 3 and further refer to Figures 14 to 17 , Figure 14 This paper shows an exploded structural diagram of the first insulating member and the second insulating member cooperating in some embodiments of this application. Figure 15 A bottom view showing the mating of a first insulating member and a second insulating member in some embodiments of this application is shown; Figure 16 It shows Figure 15 A sectional view of the EE section; Figure 17 It shows Figure 16 Enlarged structural diagram at point F. The battery cell 20 also includes a second insulating member 26, which is stacked on the outside of the bottom area 257 of the first insulating member 25. The second insulating member 26 has a plurality of second through holes 261, which connect the inner and outer sides of the second insulating member 26, and the plurality of second through holes 261 are arranged in a one-to-one correspondence with the plurality of first through holes 251 in the bottom area 257.

[0115] The battery cell 23 is embedded in the housing 22 after being wrapped by the first insulating member 25, which separates the battery cell 23 from the housing 22, reducing the risk of a short circuit caused by direct contact between the battery cell 23 and the housing 22, and achieving insulation and other protection for the battery cell 23. The manufacturing process of the battery cell 20 typically involves adding electrolyte from the top of the battery cell 20 into its interior. Part of the electrolyte seeps through the top of the battery cell 23 to the electrode plates, while most is deposited directly at the bottom of the housing 22. The battery cell 23 is wrapped by the first insulating member 25, and the electrolyte seeps through the first through-hole 251 on the first insulating member 25. A second insulating member 26 is stacked at the bottom of the first insulating member 25 wrapping the battery cell 23, further isolating the bottom of the battery cell 23 from the bottom of the housing 22, providing insulation and improving the safety performance of the battery cell 20.

[0116] Meanwhile, multiple second through holes 261 are formed on the second insulating member 26. The arrangement pattern of the second through holes 261 on the second insulating member 26 can refer to the arrangement pattern of the first through holes 251 on the bottom surface area 257 of the first insulating member 25. That is, the number of second through holes 261 on the second insulating member 26 is the same as the number of first through holes 251 on the bottom surface area 257 of the first insulating member 25, and the multiple second through holes 261 are arranged one-to-one with the multiple first through holes 251 on the bottom surface area 257. In other words, each second through hole 261 is arranged opposite to a first through hole 251 and is interconnected with it, so that the electrolyte can pass through the second through hole 261 through the second insulating member 26 and then flow into the first through hole 251 at the bottom of the first insulating member 25, so that the electrolyte can effectively wet the electrode of the cell 23 from the bottom. In some embodiments, a plurality of second through holes 261 are aligned one-to-one with a plurality of first through holes 251 on the bottom surface area 257 of the first insulating member 25; the alignment of the second through holes 261 with the first through holes 251 means that the central axis of the second through hole 261 is approximately coincident with the central axis of the first through hole 251.

[0117] In this way, the first insulating component 25 and the second insulating component 26 work together to facilitate the electrolyte to effectively wet the electrode of the cell 23 from the bottom, further improving the wetting effect after electrolyte injection, increasing injection efficiency, and improving the wettability of the electrode of the cell 23, which is conducive to meeting the requirements of higher driving range.

[0118] In some embodiments, the second insulating member 26 has a first side 262 facing the first insulating member 25 and a second side 263 facing away from the first insulating member 25.

[0119] The second insulating member 26 has a first side surface 262 and a second side surface 263 facing away from each other. The first side surface 262 of the second insulating member 26 refers to the surface facing the first insulating member 25, and the side facing the first side surface 262 is the inner side of the second insulating member 26. The second side surface 263 of the second insulating member 26 refers to the surface facing away from the first insulating member 25, and the side facing the second side surface 263 is the outer side of the second insulating member 26. A second through hole 261 connects the inner side and the outer side of the second insulating member 26.

[0120] In some embodiments, refer to Figure 15 and Figure 17 The second through hole 261 passes through the first side 262 and the second side 263.

[0121] That is, the second through hole 261 can be constructed as a through hole that integrally connects the first side 262 and the second side 263 of the second insulating member 26; the cross-sectional shape of the second through hole 261 can be circular, elliptical, rectangular, square, triangular or other irregularly shaped holes, etc., without limitation. In this way, the electrolyte flow area can be increased, making the electrolyte flow better, which is conducive to electrolyte wetting, and the structure is simple, which helps to reduce costs.

[0122] In other embodiments, the second through hole 261 is configured to include a plurality of second through holes (not shown), each of which penetrates the first side surface 262 and the second side surface 263.

[0123] The second through-hole 261 can also be constructed as a plurality of second through-holes that respectively penetrate the first side 262 and the second side 263 of the second insulating member 26. The cross-sectional area of ​​each second through-hole is smaller than the cross-sectional area of ​​the overall through-hole 261 in the previous embodiment located near the first insulating member 25. The plurality of second through-holes are arranged in a concentrated manner to form a mesh-like second through-hole 261. Thus, the plurality of second through-holes can be arranged according to certain rules to form electrolyte channels, such as rectangular array arrangement or circular array arrangement, etc. However, the size of each second through-hole can effectively block the falling off of the battery cell 23 or other foreign objects. Compared with the overall through-hole 261, although the opening area of ​​a single second through-hole is smaller, the second through-hole 261 in this embodiment can open a plurality of second through-holes in a larger area so that the sum of the opening areas of the plurality of second through-holes is not less than the opening area of ​​the overall through-hole 261. The second through hole can be a straight through hole with a constant diameter along its axial direction, or its structure can be similar to that of the integrally through first through hole 251, i.e., the cross-sectional area of ​​the second through hole on the first side 262 is smaller than the cross-sectional area of ​​the second through hole on the second side 263. No specific limitation is made here. The mesh-like second through hole 261 can be one of various shapes such as waist-shaped, triangular, circular, or square. In some embodiments, the diameter of the second through hole is less than or equal to 0.2 mm, for example, it can be equal to 0.05 mm, 0.1 mm, 0.15 mm, or 0.2 mm.

[0124] Thus, the mesh-like second through hole 261 also increases the opening area, making the electrolyte flow better and facilitating electrolyte wetting. It can improve the wetting effect after electrolyte injection. At the same time, the opening area of ​​a single second through hole is smaller, which can improve the situation of metal shavings falling off, reduce the risk of metal shavings or carbon powder falling off, reduce the internal corrosion of the battery cell 20, and reduce the safety risk of short circuit between the cell 23 and the casing 22.

[0125] In some embodiments, refer to Figure 17 The cross-sectional area of ​​the second through hole 261 on the first side 262 is smaller than the cross-sectional area of ​​the second through hole 261 on the second side 263.

[0126] In this embodiment, the second through hole 261 penetrates the first side 262 and the second side 263 of the second insulating member 26. For example, the diameter of the second through hole 261 gradually increases from the side close to the first insulating member 25 to the side away from the first insulating member 25, so that the second through hole 261 is a tapered hole as a whole, which is conducive to the electrolyte flowing into the first through hole 251 of the first insulating member 25 through the second through hole 261, thereby improving the wetting effect of the electrolyte.

[0127] Thus, the opening area of ​​the second insulating member 26 on the side away from the first insulating member 25 is larger, which increases the electrolyte flow area and allows more electrolyte to flow to the first insulating member 25. The electrolyte has better fluidity, which is conducive to the wetting of the electrolyte and improves the wetting effect. At the same time, the opening area of ​​the second insulating member 26 on the side closer to the first insulating member 25 is smaller, which can improve the situation of metal shavings falling and reduce the risk of metal shavings falling.

[0128] In some embodiments, refer to Figure 17 The diameter D7 of the second through hole 261 on the first side 262 is greater than the diameter D2 of the first through hole 251 on the outer side 253.

[0129] In other words, the opening area of ​​the second through hole 261 on the side closer to the first insulating member 25 is larger than the opening area of ​​the first through hole 251, so that the projection of the second through hole 261 on the first insulating member 25 can cover the projection of the first through hole 251 on the first insulating member 25.

[0130] In this way, by further increasing the electrolyte flow area, more electrolyte can flow through the second through hole 261 to the first through hole 251 of the first insulating component 25, thereby wetting the battery cell 23 and improving the electrolyte wetting effect.

[0131] According to some embodiments of this application, refer to Figure 2 This application provides a battery 100. The battery 100 includes a battery cell 20 provided in the above embodiments.

[0132] Since battery 100 has the same technical effect as the aforementioned battery cell 20, it will not be described again here.

[0133] According to some embodiments of this application, this application also provides an electrical device, which includes the battery 100 or battery cell 20 provided in the above embodiments, and the battery 100 and battery cell 20 are used to provide electrical energy to the electrical device.

[0134] The power supply device can be any of the aforementioned devices or systems that utilize the battery 100. Since the power supply device has the same technical effects as the battery 100 and the battery cell 20, it will not be described in detail here.

[0135] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that, The battery cell includes a battery cell, a first insulating member, and a second insulating member. The first insulating member encloses the battery cell. The first insulating member has an inner side facing the battery cell and an outer side facing away from the battery cell. The first insulating member is provided with a first through hole. Wherein, the first through hole penetrates the inner side and the outer side, the cross-sectional area of ​​the first through hole on the inner side is smaller than the cross-sectional area of ​​the first through hole on the outer side, the cross-sectional area of ​​the first through hole on the inner side is S1, the cross-sectional area of ​​the first through hole on the outer side is S2, wherein 0.3≤S1 / S2≤0.7; or, the first through hole is constructed to include a plurality of first through holes, each of the first through holes penetrating the inner side and the outer side; The first insulating element includes a large surface area, a side surface area, and a bottom surface area; wherein, at least one of the large surface area, the side surface area, and the bottom surface area is provided with a plurality of the first through holes; The second insulating element is stacked on the outside of the bottom surface area of ​​the first insulating element. The second insulating element has a plurality of second through holes, and the plurality of second through holes are arranged in a one-to-one correspondence with the plurality of first through holes in the bottom surface area. The second insulating element has a first side facing the first insulating element and a second side facing away from the first insulating element. Wherein, the second through hole penetrates the first side and the second side; or, the second through hole is constructed to include a plurality of second through holes, each of which penetrates the first side and the second side.

2. The battery cell according to claim 1, characterized in that, The diameter of the first through hole increases from the inside to the outside of the first insulating element.

3. The battery cell according to claim 1, characterized in that, The diameter of the first through hole on the inner side is less than or equal to 0.2 mm.

4. The battery cell according to claim 1, characterized in that, The diameter of the first through hole on the outer surface is greater than 0.3 mm and less than 1.5 mm.

5. The battery cell according to claim 1, characterized in that, The diameter of the first through hole is less than or equal to 0.2 mm.

6. The battery cell according to claim 1, characterized in that, The first insulating member is further provided with a plurality of crease structures; wherein, at least one of the crease structures is provided with a plurality of the first through holes arranged along the crease forming direction.

7. The battery cell according to claim 1, characterized in that, The spacing between any two adjacent first through holes is the same; or, on at least one of the large surface area, the side surface area, and the bottom surface area, the spacing between two adjacent first through holes closer to its geometric center is smaller than the spacing between two adjacent first through holes farther from its geometric center.

8. The battery cell according to claim 1, characterized in that, Multiple first through holes are distributed in the central region of at least one of the large surface area, the side surface area, and the bottom surface area.

9. The battery cell according to claim 1, characterized in that, The cross-sectional area of ​​the second through hole on the first side is smaller than the cross-sectional area of ​​the second through hole on the second side.

10. The battery cell according to claim 1, characterized in that, The diameter of the second through hole on the first side is larger than the diameter of the first through hole on the outer side.

11. A battery, characterized in that, The battery comprises a battery cell as described in any one of claims 1 to 10.

12. An electrical appliance, characterized in that, The electrical device includes the battery as described in claim 11 or the battery cell as described in any one of claims 1 to 10, wherein the battery and the battery cell are used to provide electrical energy.

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