Battery monomer, battery and electric equipment

Abstract

A battery cell (100), a battery (200), and an electric device (1000). The battery cell (100) includes an insulating film (10) and an electrode assembly (20). The insulating film (10) comprises a bottom wall (11) and a side wall (12) connected with the bottom wall (11), a containing space (13) is defined by the bottom wall (11) and the side wall (12), a gap (14) is formed between the side wall (12) and the bottom wall (11), and the gap (14) penetrates through the side wall (12) and is communicated with the containing space (13); the electrode assembly (20) is arranged in the containing space (13) and abuts against the bottom wall (11).

Description

Battery cells, batteries and electrical equipment

[0001] Priority information

[0002] This application claims priority and benefits of patent application No. 202322664868.9 filed with the State Intellectual Property Office of China on September 28, 2023, and the entire text of which is incorporated herein by reference. Technical Field

[0003] The present application relates to the field of battery technology, and in particular to a battery cell, a battery, and an electrical device. Background Art

[0004] In related technologies, a battery cell typically includes an electrode assembly and an insulating film. The insulating film wraps the electrode assembly to reduce the risk of short circuits caused by contact between the electrode assembly and other battery cell components. Because the electrode assembly is wrapped in the insulating film, the area directly in contact with the electrolyte is reduced, which affects the electrode assembly's wetting effect. Therefore, improving the electrode assembly's wetting effect has become a technical problem to be solved.

[0005] Summary of the Invention

[0006] The present application provides a battery cell, a battery, and an electrical device, which can solve the problem of poor wetting effect of the electrode assembly after the electrode assembly is wrapped by an insulating film.

[0007] The battery cell according to the embodiment of the present application includes an insulating film and an electrode assembly. The insulating film includes a bottom wall and side walls connected to the bottom wall. The bottom wall and the side walls define a storage space. A gap is formed between the side walls and the bottom wall. The gap passes through the side walls and communicates with the storage space. The electrode assembly is disposed within the storage space and abuts against the bottom wall.

[0008] In the battery cell of the embodiment of the present application, the voids extend through the sidewalls and connect to the storage space. This facilitates the passage of electrolyte into the storage space through the voids, thereby improving the wetting effect of the electrode assembly. Furthermore, the provision of the voids allows the electrode assembly to maintain communication with the exterior of the storage space. Therefore, if thermal runaway of the electrode assembly occurs, the gas within the storage space can flow freely, thereby reducing safety risks.

[0009] In certain embodiments, the side wall includes a first wall and a second wall connected to the first wall, and the gap is formed between one of the first wall and the second wall and the bottom wall.

[0010] In this way, due to the gap formed between the first wall or the second wall and the bottom wall, the electrolyte can enter the accommodation space through the gap, thereby being more evenly distributed around the electrode assembly, thereby improving the contact between the electrode assembly and the electrolyte, and further enhancing the infiltration effect of the electrode assembly. In addition, this can also reduce the risk of the bottom wall and side walls breaking and detaching.

[0011] In certain embodiments, the area of ​​the first wall is greater than the area of ​​the second wall, and the gap is formed between the second wall and the bottom wall.

[0012] In this way, the second wall is smaller than the first wall, making it easier for the electrolyte to cover the area between the second wall and the bottom wall. This means that the gap formed between the second wall and the bottom wall allows the electrolyte to enter the storage space more easily through this gap. In addition, this also allows the connection between the bottom wall and the side wall to be larger, reducing the risk of the bottom wall and the side wall breaking and separating.

[0013] In certain embodiments, the gap extends along an edge of the first wall or the second wall to a corner of the first wall and the second wall to separate the first wall from the bottom wall or the second wall from the bottom wall.

[0014] In this way, the gap is extended to the corner of the first wall and the second wall, so that the size of the gap is larger, which can improve the wetting effect of the electrode assembly.

[0015] In some embodiments, the number of the first wall and the number of the second wall are both two, the two first walls are arranged opposite to each other, and the two second walls are arranged opposite to each other, the first wall and the second wall form a plurality of corners, and along the circumference of the insulating film, the pore extends from one of the corners to another adjacent corner.

[0016] In this way, the gap extends from one corner to another adjacent corner along the circumference of the insulating film. The size of the gap is large, which will create a continuous channel, allowing the electrolyte to be evenly distributed around the electrode assembly through the gap, thereby improving the wetting effect of the electrode assembly.

[0017] In some embodiments, the first wall is connected to the bottom wall, and the gap is formed between the second wall and the bottom wall.

[0018] In this way, the first wall is connected to the bottom wall, which maintains a connection between the bottom wall and the side walls. This allows the electrode assembly to be wrapped by the insulating film in this area, ensuring the insulating performance of the insulating film in this area. A gap is formed between the second wall and the bottom wall, allowing the electrolyte to enter the accommodation space through the gap, thereby improving the infiltration effect of the electrode assembly.

[0019] In some embodiments, there are two first walls, the two first walls are arranged opposite to each other, the second wall includes two folding sheets, the two folding sheets are connected to the two first walls in a one-to-one correspondence, the two folding sheets are partially stacked, and the gap is formed between the two folding sheets and the bottom wall.

[0020] Designing the insulating film as a folded sheet can reduce assembly difficulty. The insulating film can be quickly wrapped around the circumference of the electrode assembly during assembly, reducing the probability of burrs and other defects caused by scratches during assembly. Furthermore, the two folded sheets are partially stacked, which improves the insulation performance of the second wall and reduces the risk of short circuits caused by contact between the electrode assembly and other components outside the second wall.

[0021] In certain embodiments, the battery cell includes a connector, one end of which connects the two folded sheets, and the other end of which is fixed to a side of the bottom wall away from the electrode assembly, and the connector partially covers the gap.

[0022] In this way, since one end of the connector is connected to the two folding sheets and the other end is fixed to one side of the bottom wall, it provides a stable support and fixing point, thereby reducing the probability of uncontrolled warping and deformation of the folding sheets during assembly or battery operation.

[0023] In some embodiments, the edge of the bottom wall protrudes from the outer surface of the second wall at the gap. This protruding edge of the bottom wall provides a safe distance between the electrode assembly and other components of the battery cell, reducing the probability of contact between the electrode assembly and other components of the battery cell, thereby ensuring that the insulating film's insulation function does not fail.

[0024] In some embodiments, the height of the gap ranges from 0.05 mm to 10 mm. Thus, limiting the height of the gap to 0.05 mm to 10 mm can ensure that the electrode assembly has a good wetting effect, and the gap has little effect on the insulation performance of the insulating film.

[0025] The battery of the embodiment of the present application includes the battery cell described in any of the above embodiments. As such, since the electrode assembly can be effectively wetted in the battery cell and the function of the insulating film is not significantly affected, the battery of the embodiment of the present application has good performance and can operate continuously and stably in a safe environment.

[0026] The electrical equipment of the embodiments of the present application includes the battery cell or the battery described in any of the above embodiments. As such, since the electrode assembly in the battery cell or battery can be effectively wetted and the function of the insulating film is not significantly affected, the electrical equipment of the embodiments of the present application has good performance and can operate continuously and stably in a safe environment.

[0027] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0029] FIG1 is a schematic diagram of the structure of an electrical device provided in some embodiments of the present application;

[0030] FIG2 is a schematic structural diagram of a battery provided in some embodiments of the present application;

[0031] FIG3 is a disassembled diagram of a battery cell provided in some embodiments of the present application;

[0032] FIG4 is a schematic structural diagram of an insulating film provided in some embodiments of the present application;

[0033] FIG5 is an enlarged view of part a of FIG4 ;

[0034] FIG6 is a schematic structural diagram of an insulating film provided in some embodiments of the present application;

[0035] FIG7 is an enlarged view of part b of FIG6;

[0036] FIG8 is a schematic structural diagram of an insulating film in a flattened state provided by some embodiments of the present application;

[0037] FIG9 is an enlarged view of part c of FIG8 .

[0038] Explanation of the accompanying drawings: Battery cell 100; insulating film 10; bottom wall 11; side wall 12; accommodating space 13; gap 14; electrode assembly 20; first wall 120; second wall 121; corner 122; folding sheet 1210; connector 30; battery 200; battery case 201; electrical equipment 1000; controller 300; motor 400; housing 40; bottom plate 41; cover plate 42; through hole 50. DETAILED DESCRIPTION

[0039] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be understood as limiting the present application.

[0040] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present application, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0041] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or mutual communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0042] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0043] The disclosure below provides many different embodiments or examples for realizing different structures of the present application. In order to simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present application. In addition, the present application may repeat reference numbers and / or reference letters in different examples, and such repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art will appreciate the application of other processes and / or the use of other materials.

[0044] Currently, market developments indicate that batteries are increasingly being used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric cars, as well as in aerospace and other fields. As battery applications continue to expand, market demand is also growing.

[0045] During battery manufacturing, an insulating film is typically placed outside the electrode assembly to reduce contact between the electrode assembly and the battery casing, thereby minimizing the risk of battery failure. This insulating film isolates the electrode assembly from the battery casing, ensuring proper functioning of the electrode assembly.

[0046] However, the provision of the insulating film hinders the contact between the electrode assembly and the electrolyte, resulting in poor wetting of the electrode assembly. To address this problem, gaps are provided in the insulating film, allowing the electrolyte to contact the electrode assembly through the gaps, thereby improving the wetting effect of the electrode assembly.

[0047] The electrical device according to the embodiments of the present application includes a battery cell or battery according to any of the following embodiments. Thus, the electrical device according to the embodiments of the present application. Thus, since the electrode assembly in the battery cell or battery can be effectively wetted and the function of the insulating film is not significantly affected, the electrical device according to the embodiments of the present application has good performance and can operate continuously and stably in a safe environment.

[0048] Specifically, electric devices may use batteries or battery cells as power sources, and may include, but are not limited to, mobile phones, tablets, laptops, electric toys, electric tools, battery-powered vehicles, electric cars, ships, spacecraft, etc. Electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft may include airplanes, rockets, space shuttles, and spacecraft, etc.

[0049] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electric device 1000 according to an embodiment of the present application.

[0050] Please refer to Figure 1, which is a schematic diagram of the structure of an electric device 1000 provided in some embodiments of the present application. A battery 200 is installed inside the vehicle. Battery 200 can be located at the bottom, front, or rear of the vehicle. Battery 200 can be used to power the vehicle, for example, as the vehicle's operating power source.

[0051] The vehicle may further include a controller 300 and a motor 400 . The controller 300 is used to control the battery 200 to supply power to the motor 400 , for example, to meet the vehicle's power requirements for starting, navigating, and driving.

[0052] In the embodiment of the present application, the battery 200 can not only serve as the operating power source of the vehicle, but also serve as the driving power source of the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0053] Please refer to Figure 2, which is a schematic diagram of the structure of a battery 200 provided in some embodiments of the present application. The battery 200 according to an embodiment of the present application includes a battery cell 100 according to any of the following embodiments. As such, because the electrode assembly 20 can be effectively wetted in the battery cell 100 and the function of the insulating film 10 is not significantly affected, the battery 200 according to the embodiment of the present application has good performance and can operate continuously and stably in a safe environment.

[0054] In the embodiments of the present application, the battery cell 100 may include a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery, etc., and the embodiments of the present application are not limited to this. The battery cell 100 may be cylindrical, flat, rectangular, or other shapes, and the embodiments of the present application are not limited to this. The battery cell 100 is generally divided into three types according to the packaging method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, and the embodiments of the present application are not limited to this.

[0055] The battery 200 generally includes a battery case 201 for encapsulating one or more battery cells 100. Multiple batteries can be housed in the battery case 201, which can prevent liquids or other foreign matter from affecting the charging or discharging of the battery cells 100. As the carrier of the battery module, the battery case 201 plays a key role in the safe operation and protection of the battery module. The battery case 201 must meet the strength and stiffness requirements and the protection level requirements of the electrical equipment casing, while providing collision protection. The shape of the battery case 201 can be a rectangular parallelepiped, a cube, etc. The battery case 201 can be cast with materials such as steel plates and aluminum alloys; new lightweight materials can also be used, such as glass fiber reinforced composite materials, carbon fiber reinforced composite materials, etc.

[0056] Please refer to Figure 3, which is a disassembled diagram of the battery cell 100 provided in some embodiments of the present application. In some embodiments, the battery cell 100 includes a shell 40, and the insulating film 10 and the electrode assembly 20 are arranged as a whole in the shell 40. The shell 40 includes a bottom plate 41 and a cover plate 42 opposite to the bottom plate 41. The bottom plate 41 and / or the cover plate 42 are provided with an explosion-proof valve. In some embodiments, the bottom plate 41 is provided with an explosion-proof valve. In some embodiments, the cover plate 42 is provided with an explosion-proof valve. The explosion-proof valve can play a protective role when the electrode assembly 20 in the shell 40 undergoes thermal runaway, and releases the high-pressure gas generated when the electrode assembly 20 undergoes thermal runaway to the outside of the shell 40 to ensure the normal operation of the battery 200.

[0057] The electrode assembly 20 is a component in the battery cell 100 where electrochemical reactions occur. One or more electrode assemblies 20 may be contained in the housing 40 of the battery cell 100. The electrode assembly 20 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly 20, and the parts of the positive and negative electrode sheets without active materials each constitute a tab. The positive and negative electrode tabs may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery 200, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tabs connect the electrode terminals to form a current loop.

[0058] Please refer to Figures 3 and 4. Figure 4 is a schematic diagram of the structure of the insulating film 10 provided in some embodiments of the present application. The battery cell 100 of the embodiment of the present application includes an insulating film 10 and an electrode assembly 20. The insulating film 10 includes a bottom wall 11 and a side wall 12 connected to the bottom wall 11. The bottom wall 11 and the side wall 12 enclose a receiving space 13. A gap 14 is formed between the side wall 12 and the bottom wall 11. The gap 14 passes through the side wall 12 and connects to the receiving space 13. The electrode assembly 20 is disposed in the receiving space 13 and abuts against the bottom wall 11.

[0059] Specifically, it is usually made of non-conductive materials, such as plastic or ceramic. The insulating film 10 can be a Mylar film, which is a tough polyester polymer film. The bottom wall 11 is the bottom of the insulating film 10, usually a flat surface. The bottom wall 11 is a major part of the insulating film 10, serving as the bottom boundary of the insulating film 10. The side wall 12 and the bottom wall 11 can be connected in an integrated manner or in a separate manner. The side wall 12 can be connected to the edge of the bottom wall 11 to enclose a storage space 13 with the bottom wall 11. The storage space 13 is an area inside the insulating film 10, used to accommodate the electrode assembly 20 and the electrolyte, etc.

[0060] The gap 14 is a notch between the side wall 12 and the bottom wall 11. The gap 14 can be formed at the interface between the side wall 12 and the bottom wall 11. The electrolyte can enter the accommodation space 13 through the gap 14. The gap 14 has a certain shape and size, and the number of gaps 14 can be one or more.

[0061] The electrode assembly 20 can be placed in the accommodation space 13, and the electrode assembly 20 can be in close contact or adhered to the bottom wall 11. The electrode assembly 20 and the electrolyte can undergo an electrochemical reaction. When the electrode assembly 20 is placed in the accommodation space 13, the insulating film 10 can be used to isolate the electrode assembly 20 from the housing 40 of the battery cell 100. At this time, the electrolyte can still contact the electrode assembly 20 through the gap 14, maintaining the wettability of the electrode assembly 20.

[0062] In the battery cell 100 of the embodiment of the present application, the gap 14 extends through the side wall 12 and is connected to the accommodating space 13. This facilitates the passage of electrolyte into the accommodating space 13 through the gap 14, thereby improving the wetting effect of the electrode assembly 20. Furthermore, the provision of the gap 14 allows the electrode assembly 20 to maintain communication with the exterior of the accommodating space 13. Therefore, if thermal runaway of the electrode assembly 20 occurs, the gas within the accommodating space 13 can flow freely, thereby reducing safety risks.

[0063] Referring to Figures 4, 5, 6, and 7, Figure 5 is an enlarged view of portion a of Figure 4, Figure 6 is a schematic structural diagram of an insulating film 10 provided in some embodiments of the present application, and Figure 7 is an enlarged view of portion b of Figure 6. In some embodiments, the sidewall 12 includes a first wall 120 and a second wall 121 connected to the first wall 120, with a gap 14 formed between one of the first wall 120 and the second wall 121 and the bottom wall 11.

[0064] Specifically, the first wall 120 and the second wall 121 can be integrally connected or separately connected. The first wall 120 and the second wall 121 can have an angle therebetween, and the first wall 120 and the second wall 121 can be connected to the bottom wall 11 separately. The number of first walls 120 and second walls 121 can be multiple, for example, two, three, four, or even more. In some embodiments, a gap 14 is formed between the first wall 120 and the bottom wall 11. In some embodiments, a gap 14 is formed between the second wall 121 and the bottom wall 11.

[0065] Thus, due to the gap 14 formed between the first wall 120 or the second wall 121 and the bottom wall 11, the electrolyte can enter the accommodation space 13 through the gap 14, thereby being more evenly distributed around the electrode assembly 20, thereby improving the contact between the electrode assembly 20 and the electrolyte, and further enhancing the infiltration effect of the electrode assembly 20. In addition, this can also reduce the risk of the bottom wall 11 and the side wall 12 breaking and separating.

[0066] Referring to FIG. 3 , in some embodiments, the area of ​​the first wall 120 is larger than the area of ​​the second wall 121 , and a gap 14 is formed between the second wall 121 and the bottom wall 11 .

[0067] Specifically, the area of ​​the first wall 120 refers to the area of ​​the largest surface on the first wall 120 , and the area of ​​the second wall 121 refers to the area of ​​the largest surface on the second wall 121 .

[0068] As a result, second wall 121 is smaller than first wall 120, making it easier for the electrolyte to cover the area between second wall 121 and bottom wall 11. This means that forming gap 14 between second wall 121 and bottom wall 11 allows the electrolyte to more easily pass through this gap and enter accommodation space 13. Furthermore, this also allows for a larger connection between bottom wall 11 and side wall 12, reducing the risk of breakage and separation between bottom wall 11 and side wall 12.

[0069] 5 and 7 , in some embodiments, the gap 14 extends along the edge of the first wall 120 or the second wall 121 to the corner 122 of the first wall 120 and the second wall 121 to separate the first wall 120 from the bottom wall 11 or the second wall 121 from the bottom wall 11 .

[0070] Specifically, the "edge of the first wall 120 or the second wall 121" refers to the edge of the first wall 120 or the second wall 121 near the bottom wall 11. The corner 122 of the first wall 120 and the second wall 121 refers to the connecting region of the first wall 120 and the second wall 121, and further refers to the corner of the connecting region. The gap 14 can separate the first wall 120 from the bottom wall 11, or separate the second wall 121 from the bottom wall 11.

[0071] In this way, the gap 14 is extended to the corner 122 between the first wall 120 and the second wall 121 , so that the size of the gap 14 is larger, which can improve the wetting effect of the electrode assembly 20 .

[0072] Please refer to Figures 4 and 6. In some embodiments, the number of the first wall 120 and the second wall 121 are both two. The two first walls 120 are arranged opposite to each other, and the two second walls 121 are arranged opposite to each other. The first wall 120 and the second wall 121 form a plurality of corners 122. Along the circumference of the insulating film 10, the gap 14 extends from one of the corners 122 to another adjacent corner 122.

[0073] Specifically, the two first walls 120 and the two second walls 121 can form a prism-like body together with the bottom wall 11. In this prism, the first walls 120 and the second walls 121 can form two, three, four, or even more corners 122. Along the circumference of the insulating film 10, the gap 14 can extend along the bottom edge region of the prism, extending from one corner to the other.

[0074] In this way, the gap 14 extends from one corner 122 to another adjacent corner 122 along the circumference of the insulating film 10. The size of the gap 14 is large, which will create a continuous channel, allowing the electrolyte to be evenly distributed around the electrode assembly 20 through the gap 14, thereby improving the wetting effect of the electrode assembly 20.

[0075] Referring to FIG. 5 and FIG. 7 , in some embodiments, the first wall 120 is connected to the bottom wall 11 , and a gap 14 is formed between the second wall 121 and the bottom wall 11 .

[0076] Specifically, the first wall 120 can be integrally connected to the bottom wall 11 or separately connected. A certain distance can be set between the second wall 121 and the bottom wall 11 in the area close to the bottom wall 11, thereby forming a gap 14 with a certain shape and structure.

[0077] Of course, the gap 14 can also be formed between the second wall 121 and the bottom wall 11 by eliminating part of the material.

[0078] In this manner, the first wall 120 is connected to the bottom wall 11, thereby maintaining a connection between the bottom wall 11 and the side wall 12. This allows the electrode assembly 20 to be wrapped by the insulating film 10 in this area, thereby ensuring the insulating performance of the insulating film 10 in this area. A gap 14 is formed between the second wall 121 and the bottom wall 11, allowing the electrolyte to enter the accommodation space 13 through the gap 14, thereby improving the infiltration effect of the electrode assembly 20.

[0079] Please refer to Figures 4, 5, 6 and 7. In some embodiments, there are two first walls 120, and the two first walls 120 are arranged opposite to each other. The second wall 121 includes two folding sheets 1210, and the two folding sheets 1210 are connected to the two first walls 120 in a one-to-one correspondence. The two folding sheets 1210 are partially stacked, and a gap 14 is formed between the two folding sheets 1210 and the bottom wall 11.

[0080] Specifically, the insulating film 10 can be folded to cover the electrode assembly 20, with the bottom wall 11 of the insulating film 10 serving as a support surface. The insulating film 10 is folded along the connection between the first wall 120 and the second wall 121 and the bottom wall 11, so as to cover the electrode assembly 20 in the insulating film 10. The two folding sheets 1210 can be connected to the edges of the two first walls 120, with the first wall 120 serving as the first folding surface and the second wall 121 serving as the second folding surface. After the first wall 120 is folded, the two folding sheets 1210 are folded toward each other. After folding, the two folding sheets 1210 are partially overlapped, and a gap 14 can be formed between the folding sheets 1210 and the bottom wall 11.

[0081] Thus, designing the insulating film 10 as a folded sheet 1210 can reduce assembly difficulty. During assembly, the insulating film 10 can be quickly wrapped around the circumference of the electrode assembly 20, and the probability of defects such as burrs caused by scratches during assembly can be reduced. In this assembly method, the insulating film 10 can cover multiple electrode assemblies 20.

[0082] In addition, the two folding sheets 1210 are partially stacked, which can improve the insulation performance of the second wall 121 and reduce the risk of short circuit caused by contact between the electrode assembly 20 and other components outside the second wall 121.

[0083] 3 , in some embodiments, the battery cell 100 includes a connector 30 , one end of which connects the two folding sheets 1210 , and the other end of which is fixed to a side of the bottom wall 11 away from the electrode assembly 20 . The connector 30 partially covers the gap 14 .

[0084] Specifically, the connector 30 can be made of insulating tape, glue, or the like. One end of the connector 30 can be connected to the stacked area of ​​the two folded sheets 1210 to simultaneously connect the two folded sheets 1210. The other end of the connector 30 can be fixed to the side of the bottom wall 11 away from the electrode assembly 20 to maintain the stability of the connection. When connecting the folded sheets 1210 and the bottom wall 11, the connector 30 will partially cover the gap 14, which will reduce the probability of contact between the electrode assembly 20 and other components of the battery cell 100 (such as the housing 40), thereby improving safety.

[0085] In this way, since one end of the connector 30 is connected to the two folding sheets 1210 and the other end is fixed to one side of the bottom wall 11, it provides a stable support and fixing point, thereby reducing the probability of the folding sheet 1210 producing uncontrolled warping and deformation during assembly or operation of the battery 200.

[0086] Please refer to FIG. 5 . In some embodiments, the edge of the bottom wall 11 protrudes from the outer surface of the second wall 121 at the gap 14 .

[0087] Specifically, taking the example of the second wall 121 being a folded structure relative to the bottom wall 11 , during the folding process of the second wall 121 , there is a certain distance between the second wall 121 and the bottom wall 11 , and the second wall 121 extends toward the center of the bottom wall 11 .

[0088] In this way, through the protruding design of the edge of the bottom wall 11, a safe distance is maintained between the electrode assembly 20 and other components of the battery cell 100, reducing the probability of contact between the electrode assembly 20 and other components of the battery cell 100, thereby ensuring that the insulating function of the insulating film 10 does not fail.

[0089] Please refer to Figures 5 and 7. In some embodiments, the bottom wall 11 and / or the side wall 12 are provided with a breaking line. The breaking line may pass through the bottom wall 11 and / or the side wall 12, or may not pass through the bottom wall 11 and / or the side wall 12. The provision of the breaking line can enhance the wetting effect of the electrode assembly 20. For example, the electrolyte can contact the electrode assembly 20 through the breaking line that passes through the side wall 12. For another example, the electrolyte can be accommodated in the breaking line that does not pass through the side wall 12. In this case, the breaking line can increase the flow direction of the electrolyte, thereby enhancing the wetting effect of the electrode assembly 20.

[0090] Please refer to Figures 5 and 8. Figure 8 is a schematic diagram of the structure of the insulating film 10 in a flattened state, provided in some embodiments of the present application. In certain embodiments, the breaking line is a through hole 50, which is located near the bend of the insulating film 10. The provision of through hole 50 allows the electrolyte to pass through, thereby improving the wetting effect of the electrode assembly 20. The provision of through hole 50 also reduces the structural strength of the bend of the insulating film 10, facilitating the bending of the insulating film 10.

[0091] Referring to Figures 5 and 8 , in some embodiments, multiple through-holes 50 are arranged along the extension direction of the bend. The number of through-holes 50 can be two, three, four, or even more. The multiple through-holes 50 can be arranged in an array along the extension direction of the bend. The multiple through-holes 50 can increase the flow rate of electrolyte into the accommodation space 13, thereby improving the wetting effect of the electrode assembly 20.

[0092] Please refer to Figure 8. In some embodiments, the length range of the through hole 50 is 0.2mm to 2mm, the width range of the through hole 50 is 0.1mm to 1mm, the shape of the through hole 50 can be square, elliptical, etc., and the spacing between two adjacent through holes 50 can be 0.5mm to 3mm.

[0093] Referring to Figure 8 , in some embodiments, the ratio of the length L1 of the area where the multiple through-holes 50 are arranged to the length L2 of the bend ranges from 50% to 99%. Within this range, the number of through-holes 50 is sufficient, and the flow rate of electrolyte flowing into the accommodating space 13 is large, thereby improving the wetting effect of the electrode assembly 20. Furthermore, within this range, the structural strength of the bend is low, making it easier to bend. In one embodiment, the distance D1 from the bottom wall 11 to the through-holes 50 on the first wall 120 and / or the second wall 121 can be 2 mm to 15 mm. Furthermore, the distance D1 can be 2 mm to 10 mm.

[0094] Referring to FIG8 , in one embodiment, the distance D2 between the junction of the first wall 120 and the second wall 121 and the through hole 50 on the bottom surface is 2 mm to 15 mm. Furthermore, the distance D2 can be 2 to 10 mm. Within this range, the structural strength of the bend is low and it is easy to bend.

[0095] Please refer to Figure 9, which is an enlarged view of section c of Figure 8. In certain embodiments, the distance D3 between the gap 14 and the edge of the bottom wall 11 is 1 mm to 10 mm, and further, the distance D3 is 1 mm to 5 mm. Within this range, the electrolyte flow rate entering the accommodation space 13 through the gap 14 is large, and the electrode assembly 20 is effectively wetted. Furthermore, the gap 14 has a minimal impact on the insulation performance of the insulating film 10.

[0096] Please refer to Figures 5 and 8. In some embodiments, the corners of the bottom wall 11 are chamfered or rounded. The chamfers and rounded corners facilitate folding and reduce interference between the corners of the bottom wall 11 and other parts during assembly.

[0097] Please refer to Figure 9. In some embodiments, the range of the fillet R can be 1mm to 10mm, and further, the range can be 1mm to 5mm. Within this range, the flow rate of the electrolyte flowing into the accommodating space 13 through the gap 14 is large, and the wetting effect of the electrode assembly 20 is better; and the gap 14 has little effect on the insulation performance of the insulating film 10.

[0098] 8 , in some embodiments, multiple through holes 50 are symmetrically arranged on both sides of the length center of the bend. This arrangement can ensure the structural strength of each part of the bend and avoid defects such as cracking during bending.

[0099] Referring to FIG. 5 , in some embodiments, the height h of the gap 14 ranges from 0.05 mm to 10 mm. For example, the height h of the gap 14 can range from 0.05 mm to 9 mm, 0.1 mm to 9 mm, 0.2 mm to 8 mm, 0.5 mm to 5 mm, 5 mm to 10 mm, etc.; the height h of the gap 14 can be 0.05 mm, 0.1 mm, 0.2 mm, 5 mm, 10 mm, etc.

[0100] Specifically, the height h of the gap 14 refers to the distance between the surface of the bottom wall 11 facing the first wall 120 or the second wall 121 and the first wall 120 or the second wall 121 .

[0101] In this way, the height h of the gap 14 is limited to between 0.05 mm and 10 mm, which can ensure that the electrode assembly 20 has a good wetting effect, and the gap 14 has little effect on the insulation performance of the insulation film 10.

[0102] Please refer to Figures 3, 6, and 7. In one specific embodiment, the insulating film 10 covers the electrode assembly 20. The first wall 120 and the second wall 121 are formed with multiple corners 122. Along the circumference of the insulating film 10, gaps 14 extend from one corner 122 to another adjacent corner 122. The electrolyte enters the accommodation space 13 through the gaps 14, thereby improving the wetting effect of the electrode assembly 20.

[0103] Throughout this specification, reference to terms such as "one embodiment," "certain embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0104] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A battery cell, wherein: include: An insulating film, the insulating film comprising a bottom wall and a side wall connected to the bottom wall, the bottom wall and the side wall enclose a receiving space, a gap is formed between the side wall and the bottom wall, the gap passes through the side wall and communicates with the receiving space; An electrode assembly is disposed in the accommodating space and abuts against the bottom wall.

2. The battery cell according to claim 1, wherein: The side wall includes a first wall and a second wall connected to the first wall, and the gap is formed between one of the first wall and the second wall and the bottom wall.

3. The battery cell according to claim 2, wherein: The area of ​​the first wall is greater than that of the second wall, and the gap is formed between the second wall and the bottom wall.

4. The battery cell according to claim 2 or 3, wherein: The gap extends along an edge of the first wall or the second wall to a corner of the first wall and the second wall so that the first wall is separated from the bottom wall or the second wall is separated from the bottom wall.

5. The battery cell according to claim 4, wherein: The number of the first wall and the number of the second wall are both two, the two first walls are arranged opposite to each other, the two second walls are arranged opposite to each other, the first wall and the second wall form a plurality of corners, and along the circumference of the insulating film, the gap extends from one of the corners to another adjacent corner.

6. The battery cell according to any one of claims 2 to 5, wherein: The first wall is connected to the bottom wall, and the gap is formed between the second wall and the bottom wall.

7. The battery cell according to claim 6, wherein: There are two first walls, which are arranged opposite to each other. The second wall includes two folding sheets, which are connected to the two first walls in a one-to-one correspondence. The two folding sheets are partially stacked, and the gap is formed between the two folding sheets and the bottom wall.

8. The battery cell according to claim 7, wherein: The battery cell comprises a connector, one end of which is connected to the two folding sheets, and the other end of which is fixed to a side of the bottom wall away from the electrode assembly, and the connector covers part of the gap.

9. The battery cell according to any one of claims 6 to 8, wherein: The edge of the bottom wall protrudes from the gap to the outer surface of the second wall.

10. The battery cell according to any one of claims 1 to 9, wherein: The height of the gap ranges from 0.05 mm to 10 mm.

11. A battery, wherein: A battery cell comprising the battery cell according to any one of claims 1 to 10.

12. An electrical device, wherein: The invention comprises the battery cell according to any one of claims 1 to 10 or the battery according to claim 11.

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