Battery cell, battery and electric device

Abstract

Provided in the present application are a battery cell, a battery and an electric device. The battery cell comprises a casing, an insulating film and connectors. An outer surface of the casing comprises two first surfaces, a second surface and third surfaces, wherein the two first surfaces are disposed opposite each other; the second surface is connected to the two first surfaces; the third surfaces are connected to the two first surfaces; and the first surfaces, the second surface and the third surfaces intersect each other. The insulating film is integrally provided and comprises a main body region and ending regions, wherein the main body region covers the two first surfaces and the second surface; the ending regions cover the third surfaces and are connected to the main body region; each ending region comprises a plurality of folding tabs; the plurality of folding tabs at least partially overlap; the plurality of folding tabs comprise first folding tabs and a second folding tab; a portion of each first folding tab is self-folded to form a folded portion having a multi-layer insulating film; and the folded portion is stacked on the side of the second folding tab facing away from one third surface. At least part of one connector is connected between the folded portion and the second folding tab.

Description

Battery cell, battery and electric device

[0001] Cross-reference to Related Applications

[0002] This application claims priority to Chinese Patent Application No. 202421588625.X, filed on July 5, 2024, entitled “Battery cell, battery and electric device”, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present application relates to the technical field of batteries, in particular to a battery cell, a battery and an electric device. BACKGROUND

[0004] With the development of new energy technology, batteries are increasingly widely used, such as in mobile phones, notebook computers, electric cars, electric vehicles, electric aircraft, electric ships, electric toy cars, electric toy ships, electric toy aircraft and electric tools.

[0005] In the development of battery technology, the reliability of the battery cell directly affects the reliability, use cost and user experience of the terminal product. Therefore, how to effectively improve the reliability of the battery cell is a technical problem to be solved in the battery technology.

[0006] Practical new type content

[0007] In view of the above problems, the present application provides a battery cell, a battery and an electric device, which can effectively improve the reliability of the battery cell.

[0008] In a first aspect, the embodiments of the present application provide a battery cell, which comprises an outer shell, an insulating film and a connecting piece. The outer surface of the outer shell comprises two first surfaces, a second surface and a third surface. The two first surfaces are oppositely arranged, the second surface connects the two first surfaces, and the third surface connects the two first surfaces. The first surface, the second surface and the third surface intersect with each other. The insulating film is integrally arranged and comprises a main body area and a tail area. The main body area covers the two first surfaces and the second surface, and the tail area covers the third surface and connects the main body area. The tail area comprises a plurality of folded ears. The plurality of folded ears at least partially overlap. The plurality of folded ears comprises a first folded ear and a second folded ear. A part of the first folded ear is folded to form a folded part with multiple layers of the insulating film. The folded part is stacked on the side of the second folded ear away from the third surface. At least part of the connecting piece is connected between the folded part and the second folded ear.

[0009] The technical solution sets the connecting piece, at least part of the connecting piece is connected between the folding part and the second folding lug, to reduce or eliminate the gap between the folding part and the second folding lug, to increase the creepage distance between the shell at the position of the folding part and the external environment, to reduce the risk of insulation failure when the battery monomer has electrolyte leakage or thermal runaway and other abnormalities, to improve the reliability of the battery monomer.

[0010] In some embodiments of the first aspect, at least part of the crease edge of the folding part is exposed on a side surface of the second folding lug away from the third surface. The crease edge exposed on the side surface of the second folding lug away from the third surface has a first projection on the third surface in a direction perpendicular to the third surface, the connecting piece connected between the folding part and the second folding lug has a second projection on the third surface in a direction perpendicular to the third surface, and the first projection is located within the second projection.

[0011] The connecting piece of the technical solution can connect the crease edge exposed on the side surface of the second folding lug away from the third surface with the second folding lug, to cut off the conduction relationship between the gap between the folding part and the second folding lug and the external environment, to reduce the risk of insulation failure when the battery monomer has electrolyte leakage or thermal runaway and other abnormalities, to further reduce the risk of insulation failure, to improve the reliability of the battery monomer.

[0012] In some embodiments of the first aspect, the folding part has a third projection on the third surface in a direction perpendicular to the third surface, and the third projection coincides with the second projection.

[0013] The connecting piece of the technical solution can seal the entire gap between the folding part and the second folding lug, to further reduce the risk of insulation failure when the battery monomer has electrolyte leakage or thermal runaway and other abnormalities.

[0014] In some embodiments of the first aspect, the first folding lug covers the connecting piece.

[0015] The technical solution not only reduces the risk of the connecting piece adsorbing impurities, but also improves the consistency and appearance quality of the battery monomer.

[0016] In some embodiments of the first aspect, the outer surface of the shell comprises two third surfaces, the two first surfaces are oppositely arranged along a first direction, the two third surfaces are oppositely arranged along a second direction, each third surface connects the two first surfaces, the second surface is located on one side of the shell along a third direction and connects the first surface and the third surface, the first direction, the second direction and the third direction are perpendicular to each other. The main body region comprises two first sub-regions and a second sub-region, the two first sub-regions respectively cover the two first surfaces, and the second sub-region covers the second surface. The insulating film comprises two tailing regions, and the two tailing regions respectively cover the two third surfaces. The number of the connecting members is two, and the two connecting members are respectively arranged corresponding to the two tailing regions.

[0017] The above technical solution adopts the film wrapping manner, so that the tailing region can be located on the side surface of the shell, thereby reducing the difficulty of arranging the connecting member and improving the production efficiency of the battery monomer and reducing the cost.

[0018] In some embodiments of the first aspect, each tailing region comprises two first folded ears and a second folded ear, the first folded ear is connected to one end of the first sub-region close to the third surface, the two first folded ears in the same tailing region are oppositely folded from the two first sub-regions towards the third surface, and the second folded ear is connected to one end of the second sub-region close to the third surface and is folded from the second sub-region towards the third surface.

[0019] The thickness of the folding part of the above technical solution is small, that is, the number of layers of the insulating film of the folding part is small, on the one hand, it is beneficial to reduce the overall volume of the battery monomer, and the energy density of the battery monomer can be improved; on the other hand, since the thickness of the folding part is small, the protrusion degree at the position of the connecting member can be reduced, thereby reducing the risk of interference between the position of the connecting member and other components around the battery monomer.

[0020] In some embodiments of the first aspect, the connecting member is integrally arranged and comprises a first connecting part and two second connecting parts, the first connecting part is connected to at least one of the third surface and the second folded ear, and in the second direction, the first connecting part overlaps the two side edges of the third surface along the first direction respectively. The two second connecting parts are respectively connected to the two side edges of the first connecting part along the first direction, and the two second connecting parts are respectively connected to the inner sides of the two first folded ears.

[0021] The above technical solution can increase the layout area of the connecting member, so as to further increase the creepage distance between the outer surface and the external environment, thereby further improving the reliability of the battery monomer. In addition, by connecting the two second connecting parts through the first connecting part, the connecting member forms an integrated structure, which can simplify the arrangement difficulty of the connecting member and improve the overall production efficiency of the battery monomer.

[0022] In some embodiments of the first aspect, the two first folded ear portions located in the same end region overlap.

[0023] The above technical solution can reduce the risk of the partial outer surface of the shell being exposed to the external environment due to incomplete coverage of the end region, improve the coverage effect of the insulating film, and thus improve the reliability of the battery monomer.

[0024] In some embodiments of the first aspect, the overlapping portion of the two first folded ears located in the same end region has a fourth projection on the third surface in the second direction, the second connecting portion has a fifth projection on the third surface in the second direction, and the fourth projection and the fifth projection do not overlap.

[0025] The above technical solution can effectively reduce the thickness of the end region as a whole, i.e., reduce the maximum number of insulating film layers of the end region. On the one hand, this is conducive to reducing the overall volume of the battery monomer and improving the energy density of the battery monomer. On the other hand, since the thickness of the folded portion is small, the degree of protrusion at the position of the second connecting portion can also be reduced, thereby reducing the risk of interference between the position of the second connecting portion and other components around the battery monomer.

[0026] In some embodiments of the first aspect, the folded portions of the two first folded ears located in the same end region do not overlap.

[0027] The thickness of the end region of the above technical solution is small, i.e., the number of insulating film layers of the end region is small, which is conducive to reducing the overall volume of the battery monomer and improving the energy density of the battery monomer. In addition, a larger space can be provided for the connecting member, which can simplify the setting difficulty of the connecting member and improve the production efficiency and reduce the cost of the battery monomer.

[0028] In a second aspect, the present application provides a battery comprising the battery monomer provided by any of the embodiments of the first aspect.

[0029] In a third aspect, the present application provides a power consumption device comprising the battery monomer provided by any of the embodiments of the first aspect, which is used to provide electric energy.

[0030] The above description is only a summary of the technical solutions of the present application. In order to more clearly understand the technical means of the present application, the specific embodiments of the present application can be implemented in accordance with the content of the description, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0031] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments with reference made to the accompanying drawings. The drawings are for purposes of illustration only and are not intended to be limiting in accordance with the present application. Like reference numerals have been used wherever possible throughout the drawings and the following detailed description to refer to like parts. In the drawings:

[0032] FIG. 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application;

[0033] FIG. 2 is an exploded structural schematic diagram of a battery according to some embodiments of the present application;

[0034] FIG. 3 is a structural schematic diagram of a battery module according to some embodiments of the present application;

[0035] FIG. 4 is a structural schematic diagram of a battery cell according to some embodiments of the present application;

[0036] FIG. 5 is a structural schematic diagram of a battery cell and an insulating film during a film wrapping process according to some embodiments of the present application;

[0037] FIG. 6 is a structural schematic diagram of a battery cell and an insulating film during a film wrapping process according to some embodiments of the present application, in which a first surface of the battery cell is attached to a main body region of the insulating film, and a second surface of the battery cell is attached to the main body region of the insulating film;

[0038] FIG. 7 is a structural schematic diagram of a battery cell and an insulating film during a film wrapping process according to some embodiments of the present application, in which a third surface of the battery cell is attached to a second tab of the insulating film;

[0039] FIG. 8 is a structural schematic diagram of a battery cell, an insulating film, and a connecting member during a film wrapping process according to some embodiments of the present application;

[0040] FIG. 9 is a structural schematic diagram of a battery cell after a film wrapping process according to some embodiments of the present application.

[0041] Reference signs in the detailed description of the embodiments are as follows:

[0042] 1, vehicle; 2, battery; 3, controller; 4, motor; 5, box; 5a, first box portion; 5b, second box portion; 5c, accommodation space; 6, battery module; 7, battery cell;

[0043] 10, housing; 11, first surface; 12, second surface; 13, third surface; 20, insulating film; 21, main body region; 22, end region; 221, first tab; 2211, folded portion; 2212, crease edge; 2213, attachment portion; 222, second tab; 30, connecting member; 31, first connecting portion; 32, second connecting portion; X, first direction; Y, second direction; Z, third direction. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0045] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the specification of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings of this application are used to distinguish different objects, rather than to describe a specific order or hierarchy.

[0046] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0047] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0048] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0049] In the embodiments of the present application, the same reference signs represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of the present application shown in the drawings, and the overall thickness, length, width, and other dimensions of the integrated device are only exemplary and should not constitute any limitation on the present application.

[0050] “Multiple” appearing in the present application refers to two or more (including two).

[0051] The term “parallel” in the present application not only includes the case of absolute parallel, but also includes the case of approximately parallel as generally recognized in engineering; at the same time, “perpendicular” not only includes the case of absolute perpendicular, but also includes the case of approximately perpendicular as generally recognized in engineering.

[0052] In the embodiments of the present application, the battery cell can be a secondary battery cell, which refers to a battery cell that can be activated by charging after discharging to continue to be used.

[0053] The battery cell can be a lithium ion battery cell, a sodium ion battery cell, a sodium lithium ion battery cell, a lithium metal battery cell, a sodium metal battery cell, a lithium sulfur battery cell, a magnesium ion battery cell, a nickel hydrogen battery cell, a nickel cadmium battery cell, a lead-acid battery cell, etc., which is not limited in the embodiments of the present application.

[0054] In some embodiments, the battery cell can include a housing. The housing is used to package components such as the electrode assembly and the electrolyte. The housing can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell), or an aluminum-plastic film, etc.

[0055] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell, or a battery cell of other shapes, the prismatic battery cell includes a square battery cell, a blade-shaped battery cell, a multi-prismatic battery cell, such as a hexagonal prismatic battery cell, etc.

[0056] The battery referred to in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity.

[0057] In some embodiments, the battery can be a battery module, and when there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0058] In some embodiments, the battery can be a battery pack, and the battery pack includes a box body and a battery cell, and the battery cell or the battery module is contained in the box body.

[0059] In some embodiments, the box can be part of a chassis structure of a vehicle. For example, portions of the box can be part of a floor of the vehicle, or portions of the box can be part of cross members and longitudinal members of the vehicle.

[0060] In some embodiments, the battery can be an energy storage device. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0061] With the development of new energy technology, batteries are increasingly widely used, such as in mobile phones, laptops, electric cars, electric vehicles, electric aircraft, electric ships, electric toy cars, electric toy ships, electric toy aircraft, and electric tools.

[0062] A battery generally includes a box and a plurality of battery cells. The outer surface of the shell of the battery cell is generally covered with an insulating film to protect the battery cell.

[0063] In the current battery cell, the battery cell is generally covered with an insulating film in a meandering or U-shaped manner. The process is simple, convenient and fast. However, the above-mentioned film wrapping method generally forms a folded multi-layer insulating film in a part of the shell, and the insulating film is generally provided with adhesive on one side. In the folded multi-layer insulating film, there is a folding part formed by the self-folding of part of the insulating film, so that the folding part has no adhesive on both sides along the thickness direction of the folding part. Therefore, in the folded multi-layer insulating film, a gap is formed between the folding part and the insulating film adjacent to the folding part. When the battery cell has abnormality such as electrolyte leakage or thermal runaway, the gap between the folding part and the insulating film adjacent to the folding part will produce capillary effect, the electrolyte will enter the gap and conduct the shell and the box under the action of voltage, causing insulation failure, thereby affecting the reliability of the battery cell.

[0064] Based on the above considerations, the embodiments of the present application provide a battery cell. The battery cell includes a shell, an insulating film, and a connecting piece. The outer surface of the shell includes two first surfaces, a second surface, and a third surface. The two first surfaces are oppositely arranged. The second surface connects the two first surfaces. The third surface connects the two first surfaces. The first surface, the second surface, and the third surface intersect with each other. The insulating film is integrally arranged and includes a main area and a tail area. The main area covers the two first surfaces and the second surface. The tail area covers the third surface and connects the main area. The tail area includes a plurality of folds. The plurality of folds at least partially overlap. The plurality of folds includes a first fold and a second fold. A part of the first fold is self-folded to form a folding part with a plurality of layers of insulating film. The folding part is stacked on one side of the second fold away from the third surface. At least part of the connecting piece is connected between the folding part and the second fold.

[0065] A part of the first folding lug is folded to form a folding portion with multiple layers of insulating films, and the folding portion has no adhesive on both sides of the folding portion along the thickness direction of the folding portion. Thus, a gap is formed between the folding portion and the second folding lug. In this way, the technical solution described above reduces or eliminates the gap between the folding portion and the second folding lug by arranging the connecting member, at least a part of the connecting member is connected between the folding portion and the second folding lug, so as to increase the creepage distance between the shell and the external environment at the position of the folding portion, thereby reducing the risk of insulation failure when the battery monomer leaks electrolyte or has thermal runaway and the like, so as to improve the reliability of the battery monomer.

[0066] The technical solutions described in the embodiments of the present application are suitable for batteries and electric devices using the batteries.

[0067] The electric device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, and an electric tool, etc. The vehicle can be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile, or an extended range electric automobile, etc. The spacecraft includes an airplane, a rocket, a space shuttle, and a spacecraft, etc. The electric toy includes a fixed or mobile electric toy, such as a game console, an electric automobile toy, an electric ship toy, and an electric airplane toy, etc. The electric tool includes a metal cutting electric tool, a grinding electric tool, an assembling electric tool, and a railway electric tool, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact electric drill, a concrete vibrator, and an electric planer, etc. The embodiments of the present application do not specially limit the above electric devices.

[0068] It should be understood that the technical solutions described in the embodiments of the present application are not only limited to the above described batteries and electric devices, but also can be applied to all batteries including a battery box and electric devices using the batteries, but for the sake of simplicity, the following embodiments are described by taking an electric vehicle as an example.

[0069] FIG. 1 is a structural schematic diagram of a vehicle provided by some embodiments of the present application.

[0070] Continuing to refer to FIG. 1, the vehicle 1 is internally provided with a battery 2, which can be arranged at the bottom, the head, or the tail of the vehicle 1. The battery 2 can be used for power supply of the vehicle 1, for example, the battery 2 can be used as an operating power source of the vehicle 1.

[0071] The vehicle 1 can further include a controller 3 and a motor 4, the controller 3 is used to control the battery 2 to supply power to the motor 4, for example, to meet the working power demand of the vehicle 1 during starting, navigation, and driving.

[0072] In some embodiments of the present application, the battery 2 can not only be used as an operating power source of the vehicle 1, but also be used as a driving power source of the vehicle 1, instead of or partially instead of fuel or natural gas to provide driving power for the vehicle 1.

[0073] Figure 2 is an exploded structural schematic diagram of a battery according to some embodiments of the present application.

[0074] With continued reference to Figure 2, the battery 2 includes a housing 5 and battery cells housed in the housing 5.

[0075] The housing 5 is used to house the battery cells, and the housing 5 can be of various structures. In some embodiments, the housing 5 can include a first housing part 5a and a second housing part 5b, the first housing part 5a and the second housing part 5b are mutually coverable, and the first housing part 5a and the second housing part 5b together define a housing space 5c for housing the battery cells. The second housing part 5b can be a hollow structure with one end open, and the first housing part 5a can be a plate structure, which is coverable on the open side of the second housing part 5b to form the housing 5 with the housing space 5c; or the first housing part 5a and the second housing part 5b can both be hollow structures with one side open, and the open side of the first housing part 5a is coverable on the open side of the second housing part 5b to form the housing 5 with the housing space 5c. Of course, the first housing part 5a and the second housing part 5b can be of various shapes, such as a cylinder, a cuboid, etc.

[0076] To improve the sealing performance of the first housing part 5a and the second housing part 5b after being connected, a sealing member such as sealing glue, a sealing ring, etc. can be arranged between the first housing part 5a and the second housing part 5b.

[0077] Suppose the first housing part 5a is coverable on the top of the second housing part 5b, the first housing part 5a can also be referred to as an upper housing cover, and the second housing part 5b can also be referred to as a lower housing.

[0078] In the battery 2, the battery cells can be one or multiple. If the battery cells are multiple, the multiple battery cells can be connected in series, in parallel, or in a mixed connection, where the mixed connection means that the multiple battery cells are connected in series and in parallel. The multiple battery cells can be directly connected in series, in parallel, or in a mixed connection, and then the whole of the multiple battery cells is housed in the housing 5; of course, the multiple battery cells can first be connected in series, in parallel, or in a mixed connection to form a battery module 6, and then the multiple battery modules 6 are connected in series, in parallel, or in a mixed connection to form a whole, which is housed in the housing 5.

[0079] Figure 3 is a structural schematic diagram of a battery module according to some embodiments of the present application.

[0080] In some embodiments, with continued reference to the figure, the battery cells 7 are multiple, and the multiple battery cells 7 are first connected in series, in parallel, or in a mixed connection to form a battery module 6. The multiple battery modules 6 are then connected in series, in parallel, or in a mixed connection to form a whole, which is housed in the housing.

[0081] The plurality of battery cells 7 in the battery module 6 can be electrically connected through the busbar component to realize parallel connection, series connection or mixed connection of the plurality of battery cells 7 in the battery module 6.

[0082] FIG. 4 is a perspective structural schematic diagram of a battery cell according to some embodiments of the present application, FIG. 5 is a perspective structural schematic diagram of the position relationship between the battery cell and the insulating film during the film wrapping process according to some embodiments of the present application, FIG. 6 is a perspective structural schematic diagram of the first surface of the battery cell being attached to the main body area of the insulating film, the second surface of the battery cell being attached to the main body area of the insulating film, and the third surface of the battery cell being attached to the second folded ear of the insulating film during the film wrapping process according to some embodiments of the present application, FIG. 7 is a perspective structural schematic diagram of the third surface of the battery cell being attached to the second folded ear of the insulating film during the film wrapping process according to some embodiments of the present application, FIG. 8 is a perspective structural schematic diagram of the position relationship between the housing, the insulating film and the connecting component during the film wrapping process according to some embodiments of the present application, and FIG. 9 is a perspective structural schematic diagram of the battery cell after the film wrapping process according to some embodiments of the present application.

[0083] Referring to FIGS. 4-9, the embodiments of the present application provide a battery cell 7, which includes a housing 10, an insulating film 20 and a connecting component 30. The outer surface of the housing 10 includes two first surfaces 11, a second surface 12 and a third surface 13. The two first surfaces 11 are oppositely arranged, the second surface 12 connects the two first surfaces 11, and the third surface 13 connects the two first surfaces 11. The first surface 11, the second surface 12 and the third surface 13 intersect with each other. The insulating film 20 is integrally arranged and includes a main body area 21 and an end area 22. The main body area 21 covers the two first surfaces 11 and the second surface 12, and the end area 22 covers the third surface 13 and connects the main body area 21. The end area 22 includes a plurality of folded ears, and the plurality of folded ears at least partially overlap. The plurality of folded ears includes a first folded ear 221 and a second folded ear 222. A portion of the first folded ear 221 is folded to form a folded portion 2211 with multiple layers of the insulating film, and the folded portion 2211 is stacked on the side of the second folded ear 222 away from the third surface 13. At least a portion of the connecting component 30 is connected between the folded portion 2211 and the second folded ear 222.

[0084] Exemplarily, the shell 10 is a component for forming an internal environment of the battery cell 7. The formed internal environment can be used to accommodate an electrode assembly, an electrolyte, and other components. The electrode assembly is a component in which electrochemical reactions occur in the battery cell 7, and is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet and the negative electrode sheet have portions with active materials constituting a main body of the electrode assembly, and portions without active materials each constituting a tab. The positive electrode tab and the negative electrode tab can be located together at one end of the main body or at two ends of the main body, respectively. In the charging and discharging process of the battery, 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.

[0085] Optionally, the shell 10 can be, but is not limited to, made of a metal or a non-metal material. For example, the metal material can be copper, aluminum, or stainless steel, etc.; and the non-metal material can be polyethylene, polypropylene, or polyvinyl chloride, etc.

[0086] In some embodiments of the present application, the shell 10 is square, and the shell 10 includes a shell body and an end cover, the shell body has an opening, and the end cover covers the opening. The first surface 11, the second surface 12, and the third surface 13 are all arranged on the shell body. The first surface 11 can be understood as a large face on the circumferential side of the shell body, wherein the circumferential side refers to the surface around the opening, and the large face means a surface with a larger area on the circumferential side of the shell body. One of the second surface 12 and the third surface 13 can be understood as a small face on the circumferential side of the shell body, and the other one of the second surface 12 and the third surface 13 can be understood as a bottom face of the shell body, wherein the small face means a surface with a smaller area on the circumferential side of the shell body, and the bottom face refers to a surface of the shell body opposite to the opening.

[0087] In some examples, in the case of wrapping the square shell 10 with the insulating film 20 in a meander shape, the first surface 11 is a large face, the second surface 12 is a small face, and the third surface 13 is a bottom face.

[0088] In some examples, in the case of wrapping the square shell 10 with the insulating film 20 in a U shape, the first surface 11 is a large face, the second surface 12 is a bottom face, and the third surface 13 is a small face.

[0089] In the embodiments disclosed in the present application, the shell 10 is wrapped with the insulating film 20 on the outer surface. The insulating film 20 can play a role of insulating protection for the battery cell 7, reducing the risk of short circuit of the battery cell 7 in the normal use process, and can also make the appearance of the battery cell 7 more beautiful. Optionally, the insulating film 20 can be, but is not limited to, made of polyethylene, polypropylene, or other high molecular polymer materials.

[0090] The insulating film 20 is integrally provided, meaning that the insulating film 20 is integrally provided in a state before the housing 10 is covered.

[0091] The main body area 21 refers to a portion of the insulating film 20 that covers the housing 10 in a flat manner, and the tail area 22 refers to a portion of the insulating film 20 that covers the housing 10 in a folded manner. In other words, in the process of covering the battery cell 7 with the insulating film 20, the insulating film 20 is first covered on the first surface 11 and the second surface 12 of the housing 10 to form the main body area 21, and the portion of the insulating film 20 that exceeds the main body area 21 is folded to cover the third surface 13 of the housing 10 to form the tail area 22. It should be noted that the coverage area of the main body area 21 is generally larger than that of the tail area 22.

[0092] It can be understood that in the process of covering the third surface 13 of the housing 10 with the plurality of folded ears to form the tail area 22, the folding of each of the plurality of folded ears has a sequence.

[0093] The second folded ear 222 refers to a folded ear that is folded first and will be attached to the third surface 13 in a flat manner. The first folded ear 221 refers to a folded ear that is folded later than the second folded ear 222. Since the insulating film 20 is integrally provided, the first folded ear 221 and the second folded ear 222 are connected, and in the process of folding the second folded ear 222, a portion of the first folded ear 221 close to the second folded ear 222 will be folded synchronously, so that this portion of the first folded ear 221 is folded with another portion of the first folded ear 221 to form a folded portion 2211 with two layers of insulating film. After the first folded ear 221 is folded, the folded portion 2211 will be stacked on the side of the second folded ear 222 away from the third surface 13.

[0094] It should be noted that in the process of folding the second folded ear 222, the first folded ear 221 is affected by the folding of the second folded ear 222 to form the folded portion 2211, and according to different folding methods, the folded portion 2211 can have two layers of insulating film, three layers of insulating film, or more layers of insulating film. That is, the formation of the folded portion 2211 can be described as a folded structure with multiple layers of insulating film formed by a portion of the first folded ear 221 folding itself. In order to more clearly illustrate the embodiments of the present application, the following will be described by taking the example of folding the portion of the first folded ear 221 close to the second folded ear 222 with another portion of the first folded ear 221 to form a folded portion 2211 with two layers of insulating film.

[0095] Next, the specific structure of the embodiment of the application is introduced in a meander wrapping mode and a U-shaped wrapping mode. It should be noted that FIGS. 5 to 8 are specific step sequence structure diagrams of a U-shaped wrapping mode, and the specific step sequence structure diagrams of a meander wrapping mode can refer to the existing related step sequence diagrams, which are not shown here.

[0096] In some examples, in the case of wrapping the insulating film 20 on the square shell 10 in the U-shaped wrapping mode, the shell 10 includes two first surfaces 11, one second surface 12, and two third surfaces 13, the first surface 11 is a large surface in the circumferential side of the square shell 10, the second surface 12 is the bottom surface of the square shell 10, and the third surface 13 is a small surface in the circumferential side of the square shell 10.

[0097] The insulating film 20 has two tailing regions 22 and six ears, wherein each tailing region 22 is formed by three ears. Specifically, the insulating film 20 will first cover the two first surfaces 11 and the second surface 12 of the shell 10 to form a main body region 21 and six ears, in order to facilitate the description, the two third surfaces 13 are respectively configured as a first small surface and a second small surface, and the two tailing regions 22 are respectively configured as a first tailing region and a second tailing region. Three of the six ears are connected to one end of the main body region 21 close to the first small surface and surround the outer periphery of the first small surface, and the three ears are folded towards the first small surface to cover the first small surface to form the first tailing region; and the other three of the six ears are connected to one end of the main body region 21 close to the second small surface and surround the outer periphery of the second small surface, and the three ears are folded towards the second small surface to cover the second small surface to form the second tailing region.

[0098] In the first tailing region, two of the three ears of the first tailing region are configured as two first ears 221, and the other one of the three ears of the first tailing region is configured as a second ear 222, the two first ears 221 are respectively connected to one end of the main body region 21 close to the first small surface covered on the two first surfaces 11, and the second ear 222 is connected to one end of the main body region 21 close to the first small surface covered on the second surface 12. Each first ear 221 has a folding portion 2211.

[0099] In the second tailing region, two of the three ears of the second tailing region are configured as two first ears 221, and the other one of the three ears of the second tailing region is configured as a second ear 222, the two first ears 221 are respectively connected to one end of the main body region 21 close to the first small surface covered on the two first surfaces 11, and the second ear 222 is connected to one end of the main body region 21 close to the first small surface covered on the second surface 12. Each first ear 221 has a folding portion 2211.

[0100] In some examples, in the case of the square shell 10 being wrapped by the insulating film 20 in a meandering wrapping manner, the shell 10 includes two first surfaces 11, two second surfaces 12, and a third surface 13, the first surfaces 11 being large faces in the circumferential side of the square shell 10, the second surfaces 12 being small faces in the circumferential side of the square shell 10, and the third surface 13 being a bottom face of the square shell 10.

[0101] The insulating film 20 has a tailing region 22 and four ears. Specifically, the insulating film 20 first covers the two first surfaces 11 and the two second surfaces 12 along the circumferential direction of the shell 10 to form a main body region 21 and four ears, the four ears being folded towards the bottom face to cover the bottom face to form the tailing region 22. The four ears are configured as two first ears 221 and two second ears 222, the two first ears 221 being connected to one end of the main body region 21 covering the two first surfaces 11 near the bottom face respectively, and the two second ears 222 being connected to one end of the main body region 21 covering the two second surfaces 12 near the bottom face respectively. Each first ear 221 has two folding portions 2211.

[0102] It should be noted that the present application is also applicable to other wrapping manners, and the structure and working principle thereof are similar to the above-mentioned meandering wrapping manner and U-shaped wrapping manner, which will not be described herein again.

[0103] In the embodiments disclosed in the present application, the insulating film 20 is generally provided with adhesive on one side, that is, the insulating film 20 has an adhesive back surface. In the process of wrapping the battery monomer 7 by the insulating film 20, the insulating film 20 is first attached to the first surface 11 and the second surface 12 of the shell 10 through the adhesive back surface to form the main body region 21, and the part of the insulating film 20 beyond the main body region 21 is folded and attached to the third surface 13 of the shell 10 through the adhesive back surface to form the tailing region 22.

[0104] In the folding portion 2211, the part of the first ear 221 near the second ear 222 is folded with the other part of the first ear 221, that is, the adhesive back surface of the part of the first ear 221 near the second ear 222 is attached to the adhesive back surface of the other part of the first ear 221, so that the folding portion 2211 has no adhesive on both sides along the thickness direction thereof. Therefore, a gap is generated between the folding portion 2211 and the second ear 222. When the battery monomer 7 has abnormality such as electrolyte leakage or thermal runaway, the gap between the folding portion 2211 and the second ear 222 generates capillary effect, the electrolyte enters the gap and conducts the shell 10 and the box under the action of voltage, causing insulation failure, thereby affecting the reliability of the battery monomer 7.

[0105] The connecting piece 30 is used to seal the gap between the folding part 2211 and the second folding lug 222, so as to increase the creepage distance between the shell 10 and the external environment at the position where the folding part 2211 is located. When the battery monomer 7 has abnormality such as electrolyte leakage or thermal runaway, the risk of electrolyte entering the gap and conducting the shell 10 and the box under the action of voltage is reduced.

[0106] Exemplarily, in the process of folding the first folding lug 221 and the second folding lug 222 to form the tailing area 22, the second folding lug 222 is first folded in the direction towards the third surface 13, so that the second folding lug 222 is attached on the third surface 13 in the form of a flat, and at the same time, the folding part 2211 is formed on the first folding lug 221; then the connecting piece 30 is assembled; finally, the two first folding lugs 221 are folded towards the third surface 13 to form the tailing area 22.

[0107] It should be noted that the above-mentioned assembly of the connecting piece 30 has various forms, for example, the connecting piece 30 can be attached on the folding part 2211, or the connecting piece 30 can be attached on the second folding lug 222 at the position corresponding to the folding part 2211, or the connecting piece 30 can be attached on the inner side of the entire first folding lug 221, and so on. As long as at least part of the connecting piece 30 is connected between the folding part 2211 and the second folding lug 222, it is acceptable.

[0108] The connecting piece 30 can be directly connected with the insulating film 20, or can be limited on the insulating film 20 through other components. Alternatively, the connecting piece 30 can be, but is not limited to, double-sided adhesive tape or glue, wherein the double-sided adhesive tape can be, but is not limited to, foam double-sided adhesive tape, double-sided adhesive tape without substrate, polyethylene terephthalate double-sided adhesive tape, non-woven fabric double-sided adhesive tape or paper-based double-sided adhesive tape, and so on; the glue can be, but is not limited to, made of polyvinyl alcohol, cyanoacrylate, epoxy resin, polyurethane, light-cured resin, silicone, acrylate and the like.

[0109] The above technical solution connects at least part of the connecting piece 30 between the folding part 2211 and the second folding lug 222, so as to reduce or eliminate the gap between the folding part 2211 and the second folding lug 222, which can increase the creepage distance between the shell 10 and the external environment at the position where the folding part 2211 is located, thereby reducing the risk of insulation failure when the battery monomer 7 has abnormality such as electrolyte leakage or thermal runaway, so as to improve the reliability of the battery monomer 7.

[0110] In addition, most or all of the connecting piece 30 in the embodiment of the present application can be covered by the insulating film 20, in other words, most or all of the connecting piece 30 is not exposed outside the battery monomer 7, which is conducive to improving the consistency and appearance quality of the battery monomer 7.

[0111] In some embodiments, at least part of the crease edge 2212 of the folding portion 2211 is exposed on the side surface of the second folding lug 222 facing away from the third surface 13. The crease edge 2212 exposed on the side surface of the second folding lug 222 facing away from the third surface 13 has a first projection on the third surface 13 in a direction perpendicular to the third surface 13, and the connecting piece 30 connecting between the folding portion 2211 and the second folding lug 222 has a second projection on the third surface 13 in a direction perpendicular to the third surface 13, and the first projection is located within the second projection.

[0112] Exemplarily, the crease edge 2212 of the folding portion 2211 refers to the edge where the crease line of the folding portion 2211 is located. For example, in the case where the part of the first folding lug 221 close to the second folding lug 222 is folded with another part of the first folding lug 221 to form the folding portion 2211, the position where the crease line formed by folding the part of the first folding lug 221 close to the second folding lug 222 with the another part of the first folding lug 221 is located is the crease edge 2212. The crease edge 2212 of the folding portion 2211 can be partially exposed on the side surface of the second folding lug 222 facing away from the third surface 13 and partially covered by other parts of the insulating film 20, or the crease edge 2212 of the folding portion 2211 can be entirely exposed on the side surface of the second folding lug 222 facing away from the third surface 13.

[0113] The first projection being located within the second projection means that the connecting piece 30 can connect the crease edge 2212 exposed on the side surface of the second folding lug 222 facing away from the third surface 13 with the second folding lug 222, in other words, the crease edge 2212 exposed on the side surface of the second folding lug 222 facing away from the third surface 13 is connected with the second folding lug 222 through the connecting piece 30. The gap between the crease edge 2212 exposed on the side surface of the second folding lug 222 facing away from the third surface 13 and the second folding lug 222 is sealed.

[0114] The crease edge 2212 of the folding portion 2211 is the closest place to the gap between the folding portion 2211 and the second folding lug 222 and the external environment, and the crease edge 2212 exposed on the side surface of the second folding lug 222 facing away from the third surface 13 can be understood as the entrance of the electrolyte into the gap, therefore, closing this entrance, that is, sealing the gap between the crease edge 2212 exposed on the side surface of the second folding lug 222 facing away from the third surface 13 and the second folding lug 222, can block the electrolyte outside when the battery monomer 7 has abnormality such as electrolyte leakage or thermal runaway, and block the electrolyte from entering the gap.

[0115] The connecting piece 30 in the technical solution can connect the crease edge 2212 exposed on the side surface of the second folding ear 222 away from the third surface 13 to the second folding ear 222, cut off the conductive relationship between the gap between the folding part 2211 and the second folding ear 222 and the external environment, and thus can block the electrolyte from entering the gap when the battery monomer 7 has abnormality such as electrolyte leakage or thermal runaway, further reduce the risk of insulation failure, and improve the reliability of the battery monomer 7.

[0116] In some embodiments, the folding part 2211 has a third projection on the third surface 13 in a direction perpendicular to the third surface 13, and the third projection coincides with the second projection.

[0117] Exemplarily, the third projection coincides with the second projection, which can also be understood as that the third projection of the folding part 2211 on the third surface 13 in a direction perpendicular to the third surface 13 is located in the second projection of the connecting piece 30 on the third surface 13 in a direction perpendicular to the third surface 13. That is, the connecting piece 30 can connect the entire folding part 2211 to the second folding ear 222, in other words, the entire folding part 2211 is connected to the second folding ear 222 through the connecting piece 30.

[0118] The connecting piece 30 in the technical solution can seal the gap between the entire folding part 2211 and the second folding ear 222, and thus can further reduce the risk of insulation failure when the battery monomer 7 has abnormality such as electrolyte leakage or thermal runaway.

[0119] In some embodiments, the connecting piece 30 is profiled, the structure shape of the connecting piece 30 is matched with the structure shape of the folding part 2211, the number of the connecting piece 30 is matched with the number of the folding part 2211, and the connecting piece 30 is arranged on the inner side of the entire folding part 2211, in other words, the connecting piece 30 is arranged on the side of the entire folding part 2211 facing the third surface 13. As an example, the number of the folding part 2211 is four, the number of the connecting piece 30 is four, and the four connecting pieces 30 and the four folding parts 2211 are arranged one by one.

[0120] In some embodiments, the connecting piece 30 is profiled, the structure shape of the connecting piece 30 is matched with the structure shape of the first folding ear 221, the number of the connecting piece 30 is matched with the number of the first folding ear 221, and the connecting piece 30 connects the inner side of the entire first folding ear 221, in other words, the connecting piece 30 is arranged on the side of the entire first folding ear 221 facing the third surface 13. As an example, the number of the first folding ear 221 is four, the number of the connecting piece 30 is four, and the four connecting pieces 30 and the four first folding ears 221 are arranged one by one.

[0121] In some embodiments, the connecting piece 30 is a one-piece membrane structure. In the process of folding the first and second flaps 221 and 222 to form the tailing area 22, the second flap 222 is first folded in the direction towards the third surface 13, so that the second flap 222 is attached to the third surface 13 in a flat manner, and at the same time, the first flap 221 forms a folding portion 2211; then, the connecting piece 30 is arranged on at least one of the third surface 13, the side of the second flap 222 away from the third surface 13, and the inner side of the first flap 221; finally, the two first flaps 221 are folded towards the third surface 13 to form the tailing area 22. The specific arrangement position of the connecting piece 30 can have multiple cases, as long as it can realize the connection of at least part of the connecting piece 30 between the folding portion 2211 and the second flap 222.

[0122] In some embodiments, the first flap 221 covers the connecting piece 30.

[0123] Exemplarily, the connecting piece 30 is located on the side of the first flap 221 close to the third surface 13, in other words, the projection of the connecting piece 30 on the third surface 13 in the direction perpendicular to the third surface 13 is located within the projection of the first flap 221 on the third surface 13 in the direction perpendicular to the third surface 13. So that the connecting piece 30 will not be exposed outside the battery monomer 7.

[0124] The above technical solutions not only can reduce the risk of the connecting piece 30 adsorbing impurities, but also can improve the consistency and appearance quality of the battery monomer 7.

[0125] In some embodiments, the outer surface of the shell 10 includes two third surfaces 13, the two first surfaces 11 are oppositely arranged along the first direction X, the two third surfaces 13 are oppositely arranged along the second direction Y, each third surface 13 connects the two first surfaces 11, the second surface 12 is located on one side of the shell 10 along the third direction Z and connects the first surface 11 and the third surface 13, and the first direction X, the second direction Y and the third direction Z are perpendicular to each other. The main area 21 includes two first sub-areas and a second sub-area, the two first sub-areas are respectively covered on the two first surfaces 11, and the second sub-area is covered on the second surface 12. The insulating film 20 includes two tailing areas 22, and the two tailing areas 22 are respectively covered on the two third surfaces 13. The number of connecting pieces 30 is two, and the two connecting pieces 30 are respectively arranged corresponding to the two tailing areas 22.

[0126] Exemplarily, the shell 10 is a square shell 10, the two first surfaces 11 can be understood as two large faces of the circumferential side of the shell 10, the second surface 12 can be understood as the bottom surface of the shell 10, and the two third surfaces 13 can be understood as two small faces of the circumferential side of the shell 10. The insulation film 20 has two tailing regions 22 and six ears, wherein each tailing region 22 is formed by three ears.

[0127] As an example, the insulation film 20 can first cover one first surface 11 of the shell 10 to form one first sub-region, then the insulation film 20 is folded towards the second surface 12 and covers the second surface 12 to form a second sub-region, then the insulation film 20 is folded towards another first surface 11 of the shell 10 to form another first sub-region and six ears, then three of the six ears are folded towards one of the two third surfaces 13 to form one tailing region 22, and the other three of the six ears are folded towards the other of the two third surfaces 13 to form another tailing region 22.

[0128] As another example, the insulation film 20 can also first cover the second surface 12 of the shell 10 to form a second sub-region, then the insulation film 20 is folded towards the two first surfaces 11 and covers the two first surfaces 11 to form two first sub-regions and six ears, then three of the six ears are folded towards one of the two third surfaces 13 to form one tailing region 22, and the other three of the six ears are folded towards the other of the two third surfaces 13 to form another tailing region 22.

[0129] The two connectors 30 are respectively arranged corresponding to the two tailing regions 22, which means that one of the two connectors 30 is arranged in one of the two tailing regions 22, and the other of the two connectors 30 is arranged in the other of the two tailing regions 22. Further explanation is that one of the two connectors 30 is arranged in one of the two tailing regions 22, and the other of the two connectors 30 is arranged in the other of the two tailing regions 22.

[0130] The above technical solution adopts a film wrapping manner, so that the tailing region 22 can be located on the side surface of the shell 10, thereby reducing the difficulty of arranging the connector 30 and facilitating the improvement of the production efficiency of the battery monomer 7 and the reduction of the cost.

[0131] In some embodiments, each tailing region 22 includes two first ears 221 and a second ear 222, the first ear 221 is connected to one end of the first sub-region close to the third surface 13, the two first ears 221 located in the same tailing region 22 are respectively folded from the two first sub-regions towards the third surface 13, and the second ear 222 is connected to one end of the second sub-region close to the third surface 13 and is folded from the second sub-region towards the third surface 13.

[0132] Exemplarily, for the convenience of description, the two third surfaces 13 are respectively configured as a first facet and a second facet, and the two tailing regions 22 are respectively configured as a first tailing region and a second tailing region. Three of the six flaps are connected to one end of the main body region 21 close to the first facet and surround the outer periphery of the first facet, and the three flaps are folded towards the first facet to cover the first facet to form the first tailing region; and the other three of the six flaps are connected to one end of the main body region 21 close to the second facet and surround the outer periphery of the second facet, and the three flaps are folded towards the second facet to cover the second facet to form the second tailing region.

[0133] In the first tailing region, two of the three flaps of the first tailing region are configured as two first flaps 221, and the other one of the three flaps of the first tailing region is configured as a second flap 222, the two first flaps 221 are respectively connected to two first sub-regions close to the first facet, and the second flap 222 is connected to the second sub-region close to the first facet. Each first flap 221 has a folding portion 2211.

[0134] In the second tailing region, two of the three flaps of the second tailing region are configured as two first flaps 221, and the other one of the three flaps of the second tailing region is configured as a second flap 222, the two first flaps 221 are respectively connected to two first sub-regions close to the first facet, and the second flap 222 is connected to the second sub-region close to the first facet. Each first flap 221 has a folding portion 2211.

[0135] In some examples, the first flap 221 also has a cutout, and the cutout is arranged close to the second flap 222. The presence of the cutout can further reduce the area of the folding portion 2211 in the process of forming the folding portion 2211 by folding the first flap 221 by the second flap 222.

[0136] The thickness of the folding portion 2211 of the above-mentioned package mode is small, that is, the number of layers of the insulating film 20 of the folding portion 2211 is small. On the one hand, this is beneficial to reducing the overall volume of the battery monomer 7 and can improve the energy density of the battery monomer 7. On the other hand, since the thickness of the folding portion 2211 is small, the degree of protrusion at the position of the connecting piece 30 can also be reduced, thereby reducing the risk of interference between the position of the connecting piece 30 and other components around the battery monomer 7.

[0137] In some embodiments, the connecting member 30 is integrally provided and includes the first connecting portion 31 and the two second connecting portions 32. The first connecting portion 31 is connected to at least one of the third surface 13 and the second folded ear 222, and in the second direction Y, the first connecting portion 31 overlaps the two side edges of the third surface 13 in the first direction X, respectively. The two second connecting portions 32 are connected to the two side edges of the first connecting portion 31 in the first direction X, respectively, and the two second connecting portions 32 are connected to the inner sides of the two first folded ears 221, respectively.

[0138] Exemplarily, the integrally provided connecting member 30 means that the connecting member 30 is integrally provided in the form before the folding of the folded portion 2211 and the second folded ear 222. In some examples, the integrally provided connecting member 30 is a film-like structure, and the film-like structure can be a double-sided adhesive tape.

[0139] In the process of folding the first folded ear 221 and the second folded ear 222 to form the end zone 22, the second folded ear 222 is first folded in the direction towards the third surface 13, so that the second folded ear 222 is attached to the third surface 13 in the form of a flat sheet, and at the same time, the folded portion 2211 is formed on the first folded ear 221; then, the first connecting portion 31 of the connecting member 30 is connected to at least one of the third surface 13 and the second folded ear 222, and the two second connecting portions 32 of the connecting member 30 are connected to the inner sides of the two first folded ears 221, respectively; finally, the two first folded ears 221 are folded towards the third surface 13 to form the end zone 22.

[0140] The above technical solution can increase the layout area of the connecting member 30, further increase the creepage distance between the outer surface and the external environment, and further improve the reliability of the battery monomer 7. In addition, by connecting the two second connecting portions 32 through the first connecting portion 31, the connecting member 30 forms an integrated structure, which can simplify the setting difficulty of the connecting member 30 and improve the overall production efficiency of the battery monomer 7.

[0141] In some embodiments, the two first folded ears 221 located in the same end zone 22 partially overlap.

[0142] Exemplarily, for ease of description, the part of the first folded ear 221 excluding the folded portion 2211 is configured as a fitting portion 2213, in other words, the part of the first folded ear 221 that is not self-folded is configured as the fitting portion 2213. The fitting portion 2213 has a single-layer insulating film 20, and the two first folded ears 221 located in the same end zone 22 partially overlap, so as to form a laminated structure with multiple layers of insulating films in the end zone 22.

[0143] In some examples, in the same end area 22, the abutting portions 2213 of the two first folded ears 221 partially overlap, and the folded portions 2211 of the two first folded ears 221 also partially overlap. In this way, the first layer structure with two layers of insulating films, the second layer structure with three layers of insulating films, and the third layer structure with five layers of insulating films can be formed in the end area 22. Among them, the first layer structure is formed by the abutting portions 2213 of the two first folded ears 221 overlapping, a part of the second layer structure is formed by the abutting portions 2213 of the two first folded ears 221 and the second folded ear 222 overlapping, another part of the second layer structure is formed by the folded portions 2211 of each first folded ear 221 and the second folded ear 222 overlapping, and the third layer structure is formed by the folded portions 2211 of the two first folded ears 221 and the second folded ear 222 overlapping.

[0144] In some examples, in the same end area 22, the abutting portions 2213 of the two first folded ears 221 partially overlap, and the folded portions 2211 of the two first folded ears 221 do not overlap. In this way, the first layer structure with two layers of insulating films and the second layer structure with three layers of insulating films can be formed in the end area 22. Among them, the first layer structure is formed by the abutting portions 2213 of the two first folded ears 221 overlapping, a part of the second layer structure is formed by the abutting portions 2213 of the two first folded ears 221 and the second folded ear 222 overlapping, and another part of the second layer structure is formed by the folded portions 2211 of each first folded ear 221 and the second folded ear 222 overlapping.

[0145] The above technical solution can reduce the risk of incomplete coverage of the end area 22, which can expose part of the outer surface of the shell 10 to the external environment, thereby improving the coverage effect of the insulating film 20, thereby improving the reliability of the battery monomer 7.

[0146] In some embodiments, the part of the two first folded ears 221 overlapping in the same end area 22 has a fourth projection on the third surface 13 along the second direction Y, and the projection of the connecting piece 30 on the third surface 13 along the second direction Y does not overlap with the fourth projection.

[0147] Illustratively, the projection of the connecting piece 30 on the third surface 13 along the second direction Y does not overlap with the fourth projection, which can also be understood as that the part of the two first folded ears 221 overlapping in the same end area 22 is not provided with the connecting piece 30. That is, the connecting piece 30 is arranged away from the part of the two first folded ears 221 overlapping in the same end area 22.

[0148] It can be understood that the connecting piece 30 itself has a certain thickness, and the presence of the connecting piece 30 increases the thickness of the insulation film 20 at the position where the connecting piece 30 is arranged. Moreover, the overlapping part of the two first folded ears 221 located in the same end area 22 itself has a large thickness.

[0149] In this way, the above technical solution can effectively reduce the thickness of the end area 22 as a whole, that is, reduce the maximum number of layers of the insulation film 20 of the end area 22. On the one hand, it is beneficial to reduce the overall volume of the battery monomer 7, and can improve the energy density of the battery monomer 7. On the other hand, since the thickness of the folded part 2211 is small, the protrusion degree at the position where the connecting piece 30 is located can also be reduced, thereby reducing the risk of interference between the position where the connecting piece 30 is located and other components around the battery monomer 7.

[0150] In some embodiments, the overlapping part of the two first folded ears 221 located in the same end area 22 has a fourth projection on the third surface 13 along the second direction Y, and the second connecting part 32 has a fifth projection on the third surface 13 along the second direction Y, and the fourth projection and the fifth projection do not overlap.

[0151] Exemplarily, the fourth projection and the fifth projection do not overlap, and it can also be understood that the second connecting part 32 is not arranged in the overlapping part of the two first folded ears 221 located in the same end area 22. That is, the second connecting part 32 is arranged away from the overlapping part of the two first folded ears 221 located in the same end area 22.

[0152] It can be understood that the second connecting part 32 of the connecting piece 30 itself has a certain thickness, and the presence of the second connecting part 32 increases the thickness of the insulation film 20 at the position where the second connecting part 32 is arranged. Moreover, the overlapping part of the two first folded ears 221 located in the same end area 22 itself has a large thickness.

[0153] In this way, the above technical solution can effectively reduce the thickness of the end area 22 as a whole, that is, reduce the maximum number of layers of the insulation film 20 of the end area 22. On the one hand, it is beneficial to reduce the overall volume of the battery monomer 7, and can improve the energy density of the battery monomer 7. On the other hand, since the thickness of the folded part 2211 is small, the protrusion degree at the position where the second connecting part 32 is located can also be reduced, thereby reducing the risk of interference between the position where the second connecting part 32 is located and other components around the battery monomer 7.

[0154] In some embodiments, the folded parts 2211 of the two first folded ears 221 located in the same end area 22 do not overlap.

[0155] Exemplarily, for the convenience of description, the part of the first folded tab 221 where the folding portion 2211 is removed is configured as the abutment portion 2213, in other words, the part of the first folded tab 221 which is not self-folded is configured as the abutment portion 2213. The abutment portion 2213 has a single layer of the insulating film 20, and the two first folded tabs 221 in the same end zone 22 partially overlap, so that a laminated structure with multiple layers of the insulating film can be formed in the end zone 22.

[0156] In some examples, in the same end zone 22, the abutment portions 2213 of the two first folded tabs 221 partially overlap, and the folding portions 2211 of the two first folded tabs 221 do not overlap. In this way, a first laminated structure with two layers of the insulating film and a second laminated structure with three layers of the insulating film can be formed in the end zone 22. The first laminated structure is formed by the abutment portions 2213 of the two first folded tabs 221, and a part of the second laminated structure is formed by the abutment portions 2213 of the two first folded tabs 221 and the second folded tab 222, and another part of the second laminated structure is formed by the folding portions 2211 of the two first folded tabs 221 and the second folded tab 222.

[0157] In some examples, in the same end zone 22, the abutment portions 2213 of the two first folded tabs 221 do not overlap, and the folding portions 2211 of the two first folded tabs 221 do not overlap. In this way, a first laminated structure with two layers of the insulating film and a second laminated structure with three layers of the insulating film can be formed in the end zone 22. The first laminated structure is formed by the abutment portions 2213 of the two first folded tabs 221 and the second folded tab 222, and the second laminated structure is formed by the folding portions 2211 of the two first folded tabs 221 and the second folded tab 222.

[0158] The end zone 22 of the above technical solution has a small thickness, that is, the end zone 22 has a small number of layers of the insulating film 20, which is beneficial to reduce the overall volume of the battery monomer 7, so as to improve the energy density of the battery monomer 7. In addition, a larger space can be provided for the connecting piece 30, the setting difficulty of the connecting piece 30 can be simplified, and the production efficiency of the battery monomer 7 can be improved and the cost can be reduced.

[0159] According to some embodiments of the present application, the present application also provides a battery including the battery monomer 7 of any of the above solutions.

[0160] According to some embodiments of the present application, the present application also provides a power utilization device including the battery monomer 7 of any of the above solutions, and the battery monomer 7 is used to provide electric energy.

[0161] In order to better understand the battery monomer 7 provided by the embodiments of the present application, based on the same inventive concept, the above battery monomer 7 in practical application is described.

[0162] The embodiment of the present application provides a battery monomer 7, the battery monomer 7 includes an outer shell 10, an insulating film 20 and two connecting pieces 30, the outer surface of the outer shell 10 includes two first surfaces 11, a second surface 12 and two third surfaces 13, the two first surfaces 11 are oppositely arranged along a first direction X, the two third surfaces 13 are oppositely arranged along a second direction Y, each third surface 13 is connected with the two first surfaces 11, the second surface 12 is located on one side of the outer shell 10 along a third direction Z and is connected with the first surface 11 and the third surface 13, and the first direction X, the second direction Y and the third direction Z are perpendicular to each other.

[0163] The insulating film 20 is integrally arranged and includes a main body area 21 and two tail areas 22, the main body area 21 includes two first sub-areas and a second sub-area, the two first sub-areas cover the two first surfaces 11 respectively, and the second sub-area covers the second surface 12, and the two tail areas 22 cover the two third surfaces 13 respectively. Each tail area 22 includes a plurality of folded ears, the plurality of folded ears are at least partially overlapped, the plurality of folded ears include a first folded ear 221 and a second folded ear 222, a part of the first folded ear 221 is folded to form a folded part 2211 with multiple layers of insulating films, and the folded part 2211 is stacked on one side of the second folded ear 222 away from the third surface 13. The two connecting pieces 30 are arranged correspondingly with the two tail areas 22 respectively, and at least part of the connecting piece 30 is connected between the folded part 2211 and the second folded ear 222.

[0164] The above technical solution can reduce or eliminate the gap between the folded part 2211 and the second folded ear 222 by arranging the connecting piece 30, at least part of the connecting piece 30 is connected between the folded part 2211 and the second folded ear 222, so that the creepage distance between the outer shell 10 and the external environment at the position of the folded part 2211 can be increased, thereby the risk of insulation failure when the battery monomer 7 occurs electrolyte leakage or thermal runaway and the like can be reduced, so that the reliability of the battery monomer 7 can be improved.

[0165] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0166] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them. Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some or all of the technical features can be replaced equivalently. These modifications or replacements do not change the essence of the corresponding technical solutions, which should be covered in the scope of the present application. In particular, the technical features mentioned in each embodiment can be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

A battery cell comprises: a housing, an outer surface of the housing comprising two first surfaces, a second surface and a third surface, the two first surfaces oppositely arranged, the second surface connecting the two first surfaces, the third surface connecting the two first surfaces, the first surface, the second surface and the third surface intersecting with each other; an insulation film integrally arranged and comprising a main body region and a tail region, the main body region covering the two first surfaces and the second surface, the tail region covering the third surface and connecting the main body region, the tail region comprising a plurality of folds, the plurality of folds at least partially overlapping, the plurality of folds comprising a first fold and a second fold, a portion of the first fold being folded back to form a folded portion having a plurality of layers of the insulation film, the folded portion being stacked on a side of the second fold facing away from the third surface; a connecting member, at least a portion of the connecting member being connected between the folded portion and the second fold. The battery cell of claim 1, wherein, At least a portion of a crease edge of the folded portion is exposed on a side surface of the second fold facing away from the third surface. The crease edge exposed on the side surface of the second fold facing away from the third surface has a first projection on the third surface in a direction perpendicular to the third surface, the connecting member connected between the folded portion and the second fold has a second projection on the third surface in the direction perpendicular to the third surface, and the first projection is located within the second projection. The battery cell of claim 2, wherein, The folded portion has a third projection on the third surface in the direction perpendicular to the third surface, and the third projection coincides with the second projection. The battery cell of any one of claims 1-3, wherein, The first fold covers the connecting member. The battery cell according to any one of claims 1 to 4, wherein The outer surface of the housing comprises two third surfaces, the two first surfaces oppositely arranged in a first direction, the two third surfaces oppositely arranged in a second direction, each of the third surfaces connecting the two first surfaces, the second surface being located on one side of the housing in a third direction and connecting the first surface and the third surface, the first direction, the second direction and the third direction being perpendicular to each other. The main body region comprises two first sub-regions and a second sub-region, the two first sub-regions respectively covering the two first surfaces, the second sub-region covering the second surface, the insulation film comprising two tail regions, the two tail regions respectively covering the two third surfaces. The number of the connecting members is two, and the two connecting members are respectively arranged corresponding to the two tail regions. Each of the tail regions comprises two first folds and the second fold, the first fold being connected to an end of the first sub-region close to the third surface, the two first folds in the same tail region oppositely folded from the two first sub-regions towards the third surface, the second fold being connected to an end of the second sub-region close to the third surface and folded from the second sub-region towards the third surface. The battery cell of claim 5, wherein, ​ The battery cell of claim 6, wherein, The connecting piece is integrally arranged and comprises a first connecting portion and two second connecting portions, the first connecting portion is connected to at least one of the third surface and the second folded ear, and in the second direction, the first connecting portion overlaps the two side edges of the third surface along the first direction respectively; The two second connecting portions are respectively connected to the two side edges of the first connecting portion along the first direction, and the two second connecting portions are respectively connected to the inner sides of the two first folded ears. The battery cell of claim 7, wherein, The two first folded ears in the same end area partially overlap. The battery cell of claim 8, wherein, The partially overlapped portions of the two first folded ears in the same end area have fourth projections on the third surface along the second direction, the second connecting portions have fifth projections on the third surface along the second direction, and the fourth projections and the fifth projections do not overlap. The battery cell of claim 6, wherein, The folding portions of the two first folded ears in the same end area do not overlap. A battery comprising a plurality of battery cells according to any one of claims 1-10. An electric device comprising a battery cell according to any one of claims 1-10, the battery cell being configured to provide electric energy.

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