Battery, battery pack and energy storage system

Abstract

The present application provides a battery, a battery pack and an energy storage system. The battery comprises a casing, a pole core, a Mylar film, an insulating porous film and a bottom supporting sheet, wherein the pole core, the Mylar film, the insulating porous film and the bottom supporting sheet are all accommodated in the casing, the bottom surface of the pole core, the Mylar film, the insulating porous film and the bottom supporting sheet are sequentially stacked, and the insulating porous film located on the bottom surface comprises a plurality of through holes. The through holes of the insulating porous film can reduce the circulation of dust falling off from the pole core between the pole core and the casing, thus reducing the possibility of micro short circuit formed between the bottom surface of the pole core and the casing.

Description

Batteries, battery packs and energy storage systems

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on November 3, 2023, with application number 202322985676.8 and application name “Batteries, Battery Packs and Energy Storage Systems”. This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on February 24, 2024, with application number 202420346249.7 and application name “Batteries, Battery Packs and Energy Storage Systems”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of battery technology, and in particular to a battery, a battery pack, and an energy storage system. Background Art

[0003] The new energy industry is developing rapidly, and battery energy storage technology has become a key supporting technology for this sector. However, when the battery is in use, the design of the battery shell being charged may cause insulation failure between the shell and the battery cell, resulting in safety risks such as positive electrode carbonization, aluminum shell breakdown short circuit, corrosion, and leakage, which reduces the safety and reliability of the battery.

[0004] Summary of the Invention

[0005] The embodiments of the present application provide a battery, a battery pack, and an energy storage system that can help improve safety and reliability.

[0006] In a first aspect, an embodiment of the present application provides a battery, which includes a shell, a pole core, a Mylar film, an insulating porous membrane and a bottom support sheet, wherein the pole core, the Mylar film, the insulating porous membrane and the bottom support sheet are all accommodated in the shell; the bottom surface of the pole core, the Mylar film, the insulating porous membrane and the bottom support sheet are stacked in sequence, and the insulating porous membrane located on the bottom surface includes multiple through holes.

[0007] The electrode core includes the electrode sheet, which is composed of granular material and a binder. However, the particles on the electrode sheet easily fall off and form dust that enters the electrolyte. This can cause a micro-short circuit between the electrode core and the battery shell, which can easily lead to safety risks such as shell corrosion, carbonization of the positive electrode, aluminum shell breakdown short circuit, and leakage.

[0008] In the battery provided by the present application, the through holes of the insulating porous membrane can reduce the circulation of dust falling from the electrode piece between the Mylar membrane and the bottom support sheet, reducing the possibility of a micro short circuit between the bottom surface of the electrode core and the shell, thereby reducing the possibility of shell corrosion, positive electrode carbonization, aluminum shell breakdown short circuit, and leakage, thereby improving the safety and reliability of the battery.

[0009] According to the first aspect, in a possible implementation, the Mylar film located on the bottom surface includes multiple first openings, the bottom support sheet includes second openings, the aperture of the through hole is smaller than the aperture of the first opening, and the aperture of the through hole is smaller than the aperture of the second opening.

[0010] In this possible implementation, by setting the aperture of the through hole to be smaller than the aperture of the first opening, and smaller than the aperture of the second opening, the circulation of dust between the bottom surface of the shell and the shell is further reduced.

[0011] According to the first aspect, in a possible implementation manner, the plurality of first openings and the plurality of second openings are arranged so as not to overlap.

[0012] In this possible implementation, the position of the first opening and the position of the second opening are staggered to avoid the first opening and the second opening being arranged along the same straight line, extending the diffusion path of dust from the bottom surface of the pole core to the shell, thereby reducing the possibility of a micro short circuit between the bottom surface and the shell.

[0013] According to the first aspect, in a possible implementation manner, the aperture range of the through hole is [0.01 μm, 50 μm].

[0014] In this possible implementation, the through hole does not allow dust with a particle size greater than 50 μm to pass through, which greatly reduces the flow of dust between the bottom surface and the shell, and greatly reduces the possibility of a micro short circuit between the pole core and the shell.

[0015] According to the first aspect, in a possible implementation manner, the insulating porous film covers the connection between the side surface and the bottom surface.

[0016] In this possible implementation, since the Mylar film and the insulating porous film are wrapped at the connection, the insulating porous film provides enhanced protection at the connection, reducing the possibility of the Mylar film being damaged at the connection, which is beneficial to reducing the possibility of a micro short circuit between the pole core and the shell.

[0017] According to the first aspect, in a possible implementation, the pole core also includes a top surface and a pole ear, the top surface and the bottom surface are arranged opposite to each other, the side surface is connected between the bottom surface and the top surface, the pole ear is arranged on the top surface and protrudes from the top surface, the Mylar film covers the side surface and the top surface, the insulating porous film covers the surface of the Mylar film away from the side surface and the top surface, the insulating porous film located on the top surface is provided with an avoidance hole, and the pole ear is passed through the avoidance hole.

[0018] In this possible implementation, the insulating porous membrane covers the side of the Mylar membrane away from the side and top surface, increasing the area of ​​the pole core covered by the insulating porous membrane, reducing the flow of dust between the side and top surface of the pole core and the shell, and further reducing the possibility of micro-short circuit between the pole core and the shell.

[0019] According to the first aspect, in one possible implementation, the electrode core further includes two adjacent side surfaces, which together with the bottom surface form a bottom corner structure, and the Mylar film wraps the bottom corner structure. The battery further includes a protective tape, which wraps around the bottom corner structure and is located on a side of the Mylar film facing away from the electrode core, with the protective tape portion located between the bottom support sheet and the insulating porous film.

[0020] According to the first aspect, in a possible implementation, the battery further includes a battery cover, which is arranged on the shell, and the pole core further includes a top surface, which is arranged opposite to the bottom surface, and an insulating protective film is provided on the side of the battery cover facing the top surface of the pole core.

[0021] The Mylar film at the bottom corner structure of the pole core is easily damaged due to the large stress it is subjected to during bending, which may cause dust in the pole core to leak from the damaged part of the Mylar film at the bottom corner structure.

[0022] In this possible implementation method, the protective tape is wrapped around the bottom corner structure. In this way, the strength of the Mylar film at the bottom corner structure is enhanced, the possibility of damage to the Mylar film at the bottom corner structure is reduced, the flow of dust between the bottom corner structure of the pole core and the shell is reduced, and the possibility of a micro short circuit between the pole core and the shell is further reduced.

[0023] According to the first aspect, in a possible implementation, the battery also includes a battery cover, which is arranged on the shell, and the battery cover, pole core, insulating porous membrane, and bottom support are arranged in sequence, and the battery cover includes a cover, an upper insulating plastic part, a lower insulating plastic part and a pole: the cover includes a first surface and a second surface arranged opposite to each other, the second surface is arranged on the side of the cover facing the bottom surface, the cover is provided with a first pole through hole passing through the first surface and the second surface, the upper insulating plastic part at least partially covers the first surface, and the upper insulating plastic part is provided with a second pole through hole; the lower insulating plastic part is located between the second surface and the pole core, the lower insulating plastic part at least partially covers the second surface, and the lower insulating plastic part is provided with a third pole through hole; the pole is passed through the third pole through hole, the first pole through hole and the second pole through hole, and the pole is electrically connected to the pole core.

[0024] According to the first aspect, in one possible implementation, the first surface includes at least one surface pore; the upper insulating plastic part is partially embedded in the surface pore of the first surface, and / or the second surface includes at least one surface pore, and the lower insulating plastic part is partially embedded in the surface pore of the second surface.

[0025] In this possible implementation, the upper insulating plastic part is partially embedded in the surface pores of the first surface, so that the upper insulating plastic part and the cover plate form an integrated structure. While improving the sealing of the battery cover plate, it can also simplify the structure of the battery cover plate and facilitate the assembly of the battery cover plate with other components.

[0026] Part of the lower insulating plastic part is embedded in the surface pores of the second surface, so that the lower insulating plastic part and the cover plate form an integrated structure. While improving the sealing of the battery cover plate, it can also simplify the structure of the battery cover plate and facilitate the assembly of the battery cover plate with other components.

[0027] According to the first aspect, in a possible implementation, there is a distance between the surface hole and the outer periphery of the first pole through hole, and there is a distance between the surface hole and the outer periphery of the cover plate.

[0028] In this possible implementation, a gap exists between the surface aperture and the periphery of the first pole through-hole to reduce the possibility of cracking of the hole wall of the first pole through-hole and thus causing cracking of the cover plate. A gap exists between the surface aperture and the outer periphery of the cover plate to reduce the possibility of cracking of the outer periphery of the cover plate and thus causing cracking of the cover plate.

[0029] According to the first aspect, in a possible implementation, the diameter range of the surface pores is [10 nm, 500 nm].

[0030] In this possible implementation, the surface pores are nanoscale pores, which can increase the contact area between the cover and the upper insulating plastic part or the cover and the lower insulating plastic part, and improve the connection strength between the cover and the upper insulating plastic part or the cover and the lower insulating plastic part.

[0031] According to the first aspect, in a possible implementation, the battery cover further includes a sealing member, and the sealing member is located between the inner wall of the first pole through hole and the outer wall of the pole.

[0032] In this possible implementation, the seal is used to achieve a sealed connection between the pole, the lower insulating plastic part, and the cover plate, thereby reducing the entry of water vapor, impurities, etc. into the interior of the battery.

[0033] According to the first aspect, in one possible implementation, the aperture of the third pole through hole is larger than the aperture of the second pole through hole, the seal includes a first sealing portion and a second sealing portion that are connected and arranged, the outer diameter of the first sealing portion is smaller than the outer diameter of the second sealing portion, the first sealing portion is at least partially located between the inner wall of the first pole through hole and the outer wall of the pole, and the second sealing portion is located between the inner wall of the third pole through hole and the outer wall of the pole.

[0034] In this possible implementation, the upper insulating plastic part, the lower insulating plastic part and the seal form a step structure to avoid the risk of electrolyte crystallization and electronic conduction caused by the gap between the upper insulating plastic part, the lower insulating plastic part and the seal.

[0035] According to the first aspect, in a possible implementation, the upper insulating plastic part also includes a main body and an extension portion protruding from the side of the main body toward the cover plate, the second pole through hole passes through the main body, the main body covers at least part of the first surface, and the extension portion is located between the inner wall of the first pole through hole and the outer wall of the pole.

[0036] In this possible implementation, the extension portion extends into the first pole through hole, and the extension portion is located between the inner wall of the first pole through hole and the outer wall of the pole, so as to reduce the possibility of a gap between the upper insulating plastic part and the cover plate, and improve the sealing of the battery cover plate.

[0037] According to the first aspect, in one possible implementation, the first sealing portion is partially located between the inner wall of the first pole through hole and the outer wall of the pole, the first sealing portion is passed through the second pole through hole, and the extension portion is located between the inner wall of the second pole through hole and the outer wall of the first sealing portion, or the end face of the extension portion away from the body is in contact with an end of the first sealing portion away from the second sealing portion.

[0038] In this possible implementation, the extension portion is located between the inner wall of the second pole through hole and the outer wall of the first sealing portion, or the end face of the extension portion away from the main body is in contact with the end of the first sealing portion away from the second sealing portion, thereby reducing the possibility of a gap between the upper insulating plastic part, the sealing part, and the cover plate, and further improving the sealing of the battery cover plate.

[0039] According to the first aspect, in a possible implementation, the sealing member further includes a first recessed portion recessed on a side of the second sealing portion facing the cover plate, and a portion of the cover plate is fixed in the first recessed portion.

[0040] In this possible implementation, the cover plate is partially fixed in the first recessed portion, thereby increasing the connection area between the cover plate and the second sealing portion, reducing the possibility of a gap between the cover plate and the second sealing portion, and improving the sealing and connection strength between the cover plate and the second sealing portion.

[0041] According to the first aspect, in a possible implementation, the seal further includes a second recessed portion, which is recessed on the circumferential wall of the second sealing portion facing the inner wall of the third pole through hole, and the inner wall of the third pole through hole forms a flange toward the pole, and the flange is fixed in the second recessed portion.

[0042] In this possible implementation, since the flange is fixedly received in the second recessed portion, the connection area between the lower insulating plastic part and the second sealing portion is increased, the possibility of a gap being generated between the lower insulating plastic part and the second sealing portion is reduced, and the sealing and connection strength between the lower insulating plastic part and the second sealing portion are improved.

[0043] According to the first aspect, in a possible implementation, a third recess is formed on an end surface of the first sealing portion away from the second sealing portion, and an embedding portion is convexly formed on a surface of the upper insulating plastic part facing the cover, and the embedding portion is fixedly received in the third recess.

[0044] In this possible implementation, an embedded portion is convexly provided on one side of the upper insulating plastic part facing the cover plate, and the embedded portion is at least partially fixedly accommodated in the third recessed portion. In this way, the connection area between the upper insulating plastic part and the first sealing part is increased, the possibility of a gap between the upper insulating plastic part and the first sealing part is reduced, and the sealing and connection strength between the upper insulating plastic part and the first sealing part are improved.

[0045] According to the first aspect, in a possible implementation manner, an insulating coating is provided on the inner wall of the housing facing the pole core.

[0046] In this possible implementation, an insulating coating is provided on the inner wall of the shell, which is used to form insulating protection on the inner wall of the shell to reduce the possibility of a micro-short circuit between the shell and the pole core when dust in the pole core falls into the shell, thereby reducing the possibility of shell corrosion, positive electrode carbonization, aluminum shell breakdown short circuit, and leakage, thereby improving the safety and reliability of the battery.

[0047] According to the first aspect, in a possible implementation manner, the inner wall includes a bottom wall, and the bottom supporting sheet is located between the insulating porous membrane and the bottom wall.

[0048] In this possible implementation, when the battery is placed upright, the bottom wall of the battery contacts the supporting surface. Dust tends to fall toward the bottom wall due to gravity, and the insulating coating on the bottom wall insulates the dust from the bottom wall, reducing the possibility of a micro-short circuit between the bottom wall and the electrode core caused by the dust.

[0049] According to the first aspect, in a possible implementation, the inner wall includes a bottom wall and four side walls connected to the bottom wall, the bottom supporting sheet is located between the insulating porous membrane and the bottom wall, and the insulating coating is coated on two opposite side walls.

[0050] In this possible implementation, when the battery is placed on its side, the side of the housing where the insulating coating's sidewall is located is used to contact the supporting surface of the battery. Dust tends to fall toward the insulating coating's sidewall due to gravity. Because the insulating coating is applied to the sidewall, the dust is insulated from the sidewall by the insulating coating, reducing the possibility of a micro-short circuit between the sidewall and the electrode core through the dust.

[0051] In a second aspect, the present application further provides a battery, comprising a shell and a pole core accommodated in the shell, wherein an insulating coating is coated on the inner wall of the shell facing the pole core.

[0052] The electrode core includes the electrode sheet, which is composed of granular material and a binder. However, the particles on the electrode sheet easily fall off and form dust that enters the electrolyte. This can cause a micro-short circuit between the electrode core and the battery shell, which can easily lead to safety risks such as shell corrosion, carbonization of the positive electrode, aluminum shell breakdown short circuit, and leakage.

[0053] In the battery provided in the second aspect, an insulating coating is provided on the inner wall of the shell, and the insulating coating is used to form insulating protection on the inner wall of the shell to reduce the possibility of a micro short circuit between the shell and the pole core when dust falling from the pole core falls into the shell, thereby reducing the possibility of shell corrosion, positive electrode carbonization, aluminum shell breakdown short circuit, and leakage, thereby improving the safety and reliability of the battery.

[0054] According to the second aspect, in a possible implementation manner, the inner wall includes a bottom wall, and the bottom supporting sheet is located between the insulating porous membrane and the bottom wall.

[0055] In this possible implementation, when the battery is placed upright, the bottom wall contacts the supporting surface. Dust tends to fall toward the bottom wall due to gravity, and the insulating coating applied to the bottom wall insulates the dust from the bottom wall, reducing the possibility of a micro-short circuit between the bottom wall and the electrode core through the dust.

[0056] According to the second aspect, in a possible implementation, the inner wall includes a bottom wall and four side walls connected to the bottom wall, the bottom supporting sheet is located between the insulating porous membrane and the bottom wall, and the insulating coating is coated on two opposite side walls.

[0057] In this possible implementation, when the battery is placed on its side, the sidewall coated with the insulating coating is used to contact the supporting surface of the battery. Dust tends to fall toward the sidewall coated with the insulating coating due to gravity. Because the sidewall is coated with the insulating coating, the dust is insulated from the sidewall, reducing the possibility of micro-short circuits between the sidewall and the electrode core through the dust.

[0058] According to the second aspect, the battery also includes a Mylar film, an insulating porous membrane and a bottom support sheet, which are all housed in a shell; the bottom surface of the pole core, the Mylar film, the insulating porous membrane and the bottom support sheet are stacked in sequence, and the insulating porous membrane located on the bottom surface includes multiple through holes.

[0059] Both the positive and negative electrodes are composed of granular materials and a binder. However, particles from the positive and negative electrodes can easily break off, forming dust that enters the electrolyte. This can cause a micro-short circuit between the electrode core and the battery casing, leading to safety risks such as casing corrosion, carbonization of the positive electrode, aluminum shell breakdown, short circuits, and electrolyte leakage.

[0060] In the battery provided in the second aspect of the present application, the through holes of the insulating porous membrane can reduce the circulation of dust between the Mylar membrane and the bottom support sheet, and reduce the possibility of micro-short circuits between the bottom surface of the electrode core and the shell, thereby reducing the possibility of shell corrosion, positive electrode carbonization, aluminum shell breakdown short circuit, and leakage, thereby improving the safety and reliability of the battery.

[0061] In a third aspect, an embodiment of the present application provides a battery, comprising a shell, a pole core, and a battery cover, wherein the pole core is housed in the shell, and the battery cover is disposed on the shell. The battery cover comprises a cover, an upper insulating plastic part, a lower insulating plastic part, and a pole: the cover comprises a first surface and a second surface arranged opposite to each other, the second surface being disposed on the side of the cover facing the bottom surface, the cover being provided with a first pole through-hole passing through the first surface and the second surface, the upper insulating plastic part covering the first surface, the upper insulating plastic part being provided with a second pole through-hole; the lower insulating plastic part being located between the second surface and the pole core, the lower insulating plastic part covering the second surface, the lower insulating plastic part being provided with a third pole through-hole; the pole being provided through the third pole through-hole, the first pole through-hole, and the first pole through-hole, forming at least one surface pore on the first surface; the upper insulating plastic part being partially embedded in the surface pore of the first surface, and / or the second surface forming at least one surface pore, the lower insulating plastic part being partially embedded in the surface pore of the second surface.

[0062] In the battery provided by the third aspect, the upper insulating plastic part is partially embedded in the surface pores of the first surface, so that the upper insulating plastic part and the cover plate form an integrated structure. While improving the sealing of the battery cover plate, it can also simplify the structure of the battery cover plate and facilitate the assembly of the battery cover plate with other components.

[0063] Part of the lower insulating plastic part is embedded in the surface pores of the second surface, so that the lower insulating plastic part and the cover plate form an integrated structure. While improving the sealing of the battery cover plate, it can also simplify the structure of the battery cover plate and facilitate the assembly of the battery cover plate with other components.

[0064] According to the third aspect, in a possible implementation, there is a distance between the surface hole and the periphery of the first pole through hole, and there is a distance between the surface hole and the outer periphery of the cover plate.

[0065] In this possible implementation, a gap exists between the surface aperture and the periphery of the first pole through-hole to reduce the possibility of cracking of the hole wall of the first pole through-hole and thus causing cracking of the cover plate. A gap exists between the surface aperture and the outer periphery of the cover plate to reduce the possibility of cracking of the outer periphery of the cover plate and thus causing cracking of the cover plate.

[0066] According to the third aspect, in a possible implementation, the surface pores are nanoscale pores, and the diameter of the nanoscale pores is in the range of [10 nm, 500 nm].

[0067] In this possible implementation, the surface pores are nanoscale pores, which can increase the contact area between the cover and the upper insulating plastic part or the cover and the lower insulating plastic part, and improve the connection strength between the cover and the upper insulating plastic part or the cover and the lower insulating plastic part.

[0068] In a fourth aspect, an embodiment of the present application provides a battery, comprising a shell, a pole core, and a battery cover, wherein the pole core is housed in the shell, and the battery cover is disposed on the shell. The battery cover comprises a cover, an upper insulating plastic part, a lower insulating plastic part, a pole, and a seal: the cover comprises a first surface and a second surface arranged opposite to each other, the second surface being disposed on the side of the cover facing the bottom surface, the cover being provided with a first pole through-hole passing through the first surface and the second surface, the upper insulating plastic part covering the first surface, and the upper insulating plastic part being provided with a second pole through-hole; the lower insulating plastic part being located between the second surface and the pole core, the lower insulating plastic part covering the second surface, and a third pole through-hole being provided along the lower insulating plastic part; the pole is passed through the third pole through-hole, the first pole through-hole, and the first pole through-hole, the seal being located between the inner wall of the first pole through-hole and the outer wall of the pole, and the seal, the upper insulating plastic part, the cover, and the lower insulating plastic part forming an integrated structure.

[0069] The seal, upper insulating plastic part, cover plate and lower insulating plastic part are an integrated structure, which improves the sealing connection between the seal, pole, lower insulating plastic part and cover plate, and reduces the entry of water vapor, impurities, etc. into the interior of the battery.

[0070] According to the fourth aspect, in one possible implementation, the aperture of the third pole through hole is larger than the aperture of the second pole through hole, the seal includes a first sealing portion and a second sealing portion that are connected and arranged, the outer diameter of the first sealing portion is smaller than the outer diameter of the second sealing portion, the first sealing portion is located between the inner wall of the first pole through hole and the outer wall of the pole, and the second sealing portion is located between the inner wall of the third pole through hole and the outer wall of the pole.

[0071] In this possible implementation, the upper insulating plastic part, the lower insulating plastic part and the seal form a stepped structure, reducing the risk of electrolyte crystallization caused by the gap between the upper insulating plastic part, the lower insulating plastic part and the seal, resulting in electronic conduction.

[0072] According to the fourth aspect, in a possible implementation, the upper insulating plastic part also includes a main body and an extension portion protruding from the side of the main body toward the cover plate, the second pole through hole passes through the main body, the main body covers at least part of the first surface, and the extension portion is located between the inner wall of the first pole through hole and the outer wall of the pole.

[0073] In this possible implementation, the extension portion extends into the first pole through hole, and the extension portion is located between the inner wall of the first pole through hole and the outer wall of the pole, so as to reduce the possibility of a gap between the upper insulating plastic part and the cover plate, and improve the sealing of the battery cover plate.

[0074] According to the fourth aspect, in one possible implementation, part of the first sealing portion is located between the inner wall of the first pole through hole and the outer wall of the pole, the remaining part of the first sealing portion is passed through the second pole through hole, and the extension portion is located between the inner wall of the second pole through hole and the outer wall of the first sealing portion, or the end of the extension portion close to the lower insulating plastic part is in contact with the end of the first sealing portion away from the second sealing portion.

[0075] In this possible implementation, the extension portion is located between the inner wall of the second pole through hole and the outer wall of the first sealing portion, or the end of the extension portion close to the lower insulating plastic part is in contact with the end of the first sealing portion away from the second sealing portion, thereby reducing the possibility of a gap between the upper insulating plastic part, the sealing part, and the cover plate, and further improving the sealing of the battery cover plate.

[0076] According to the fourth aspect, in a possible implementation, the sealing member further includes a first recessed portion recessed on a side of the second sealing portion facing the cover plate, and a portion of the cover plate is fixedly embedded in the first recessed portion.

[0077] In this possible implementation, the cover plate is partially fixed in the first recessed portion, thereby increasing the connection area between the cover plate and the second sealing portion, reducing the possibility of a gap between the cover plate and the second sealing portion, and improving the sealing and connection strength between the cover plate and the second sealing portion.

[0078] According to the fourth aspect, in a possible implementation, the seal also includes a second recessed portion, which is recessed on the circumferential wall of the second sealing portion facing the inner wall of the third pole through hole, and the inner wall of the third pole through hole forms a flange toward the pole, and the flange is fixed in the second recessed portion.

[0079] In this possible implementation, since the flange is fixedly received in the second recessed portion, the connection area between the lower insulating plastic part and the second sealing portion is increased, the possibility of a gap being generated between the lower insulating plastic part and the second sealing portion is reduced, and the sealing and connection strength between the lower insulating plastic part and the second sealing portion are improved.

[0080] According to the fourth aspect, in a possible implementation, a third recess is formed on an end face of the first sealing portion away from the second sealing portion, and an embedding portion is convexly formed on a side of the upper insulating plastic part facing the cover, and the embedding portion is fixedly received in the third recess.

[0081] In this possible implementation, an embedded portion is convexly provided on one side of the upper insulating plastic part facing the cover plate, and the embedded portion is at least partially fixedly accommodated in the third recessed portion. In this way, the connection area between the upper insulating plastic part and the first sealing part is increased, the possibility of a gap between the upper insulating plastic part and the first sealing part is reduced, and the sealing and connection strength between the upper insulating plastic part and the first sealing part are improved.

[0082] In a fifth aspect, an embodiment of the present application provides a battery, which includes a shell, a pole core and a battery cover. The pole core is accommodated in the shell, and the battery cover is arranged on the shell. An insulating protective film is provided on the side of the battery cover facing the pole core.

[0083] In a sixth aspect, an embodiment of the present application provides a battery pack, comprising a plurality of batteries as described in any one of the first to fifth aspects, wherein the plurality of batteries are connected in series or in parallel.

[0084] In the seventh aspect, an embodiment of the present application also provides an energy storage system, which includes the battery pack and power converter described in the sixth aspect, the power converter is used to convert the AC power output by an external AC power supply into DC power and output it to the battery pack, and / or, the power converter is used to convert the DC power output by the battery pack into AC power and output it to a load or a power grid.

[0085] In an eighth aspect, an embodiment of the present application provides a battery comprising a housing, a pole core, a Mylar film, and a bottom support sheet. The pole core, Mylar film, and bottom support sheet are all housed within the housing, with the bottom surface of the pole core, the Mylar film, and the bottom support sheet stacked in sequence. The insulating porous membrane comprises a plurality of through-holes, each having a pore size range of [1nm-100nm]. In the battery provided herein, the through-holes in the Mylar film can reduce the flow of dust shed from the pole piece between the bottom support sheet and the housing, thereby reducing the possibility of a micro-short circuit between the bottom surface of the pole core and the housing, thereby reducing the possibility of housing corrosion, positive electrode carbonization, aluminum shell breakdown short circuit, and leakage, thereby improving the safety and reliability of the battery.

[0086] According to the eighth aspect, in one possible implementation, the bottom support sheet includes a plurality of openings, and the plurality of openings and the plurality of through-holes are arranged non-overlappingly. The positions of the plurality of openings and the plurality of through-holes are staggered to prevent the openings of the bottom support sheet and the through-holes of the Mylar film from being aligned along the same line, thereby extending the diffusion path of dust from the bottom surface of the electrode core to the housing, thereby reducing the possibility of a micro-short circuit between the bottom surface of the electrode core and the housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] FIG1 shows a schematic diagram of a framework structure of a photovoltaic system;

[0088] FIG2 is a schematic structural diagram of a battery pack provided in some embodiments of the present application;

[0089] FIG3 is a perspective exploded schematic diagram of a battery provided in one embodiment of the present application;

[0090] FIG4 is a perspective schematic diagram of a battery provided in an embodiment of the present application with part of the housing removed;

[0091] FIG5 is a perspective schematic diagram of a housing provided in one embodiment of the present application;

[0092] FIG6 is a cross-sectional view taken along line I1 shown in FIG5;

[0093] FIG7 is a schematic diagram of a battery used in a vertical placement scenario;

[0094] FIG8 is a schematic diagram of a battery application in a first side placement scenario;

[0095] FIG9 is a schematic diagram of a battery application in a second side placement scenario;

[0096] FIG10 is a perspective schematic diagram of a pole core provided in one embodiment of the present application;

[0097] FIG11 is a side view of a battery with its housing removed provided in one embodiment of the present application;

[0098] FIG12 is a plan view of a Mylar film provided in one embodiment of the present application;

[0099] FIG13 is a schematic exploded perspective view of the Mylar film, the insulating porous film, and the bottom support sheet;

[0100] FIG14 is a plan view of a bottom support sheet, a Mylar film, and an insulating porous film stacked together according to an embodiment of the present application;

[0101] FIG15 is a schematic diagram of a three-dimensional assembly of a battery with the battery housing and battery cover removed;

[0102] FIG16 is a plan view of a bottom support sheet, a Mylar film, and an insulating porous film stacked together according to an embodiment of the present application;

[0103] FIG17 is a schematic perspective view of a partial structure of a battery provided in one embodiment of the present application;

[0104] FIG18 is a perspective schematic diagram of a battery cover provided in one embodiment of the present application;

[0105] FIG19 is a partial cross-sectional view taken along line I2-I2 of FIG18 according to one embodiment of the present application;

[0106] FIG20 is a partial cross-sectional view taken along line I2-I2 of FIG18 according to one embodiment of the present application;

[0107] FIG21 is a perspective schematic diagram of the sealing member of the battery cover shown in FIG20 ;

[0108] FIG22 is a radial cross-sectional view of the seal shown in FIG20;

[0109] FIG23 is a partial cross-sectional view taken along line I2-I2 of FIG18 according to one embodiment of the present application;

[0110] FIG24 is a partial cross-sectional view taken along line I2-I2 of FIG18 according to one embodiment of the present application;

[0111] FIG25 is a perspective schematic diagram of the sealing member of the battery cover shown in FIG24 ;

[0112] FIG26 is a partial cross-sectional view of the assembly of the cover plate, the lower insulating plastic component, and the sealing component provided in one embodiment of the present application;

[0113] FIG27 is a partial cross-sectional view of the assembly of the cover plate, the lower insulating plastic component, and the sealing component provided in one embodiment of the present application;

[0114] FIG28 is a partial cross-sectional view of the assembly of the cover plate, the lower insulating plastic component, and the sealing component provided in one embodiment of the present application;

[0115] FIG29 is a partial cross-sectional view of the assembly of a cover plate, an upper insulating plastic component, and a sealing component according to an embodiment of the present application;

[0116] FIG30 is a partial cross-sectional view of the assembly of a cover plate, an upper insulating plastic component, and a sealing component according to an embodiment of the present application;

[0117] FIG31 is a partial cross-sectional view of the assembly of a cover plate, an upper insulating plastic component, and a sealing component according to an embodiment of the present application;

[0118] FIG32 is a schematic diagram of a battery cover provided with an insulating protective film according to an embodiment of the present application. DETAILED DESCRIPTION

[0119] FIG1 shows a schematic diagram of the framework structure of a photovoltaic system. As shown in FIG1 , the photovoltaic system includes a photovoltaic array 110, a power grid 130, an external load 140, and an energy storage system 150. The energy storage system 150 includes a battery pack 100 and a power converter 200. The power converter 200 is used to convert the AC power output by the external AC power source into DC power and output it to the battery pack 100, and / or the power converter 200 is used to convert the DC power output by the battery pack 100 into AC power and output it to the external load 140 or the power grid 130. The power converter 200 can integrate a DC / DC conversion circuit and a DC / AC conversion circuit. The battery pack 100 can be located between the DC / DC conversion circuit and the DC / AC conversion circuit. The electric energy generated by the photovoltaic array 110 can be converted into DC power by the DC / DC conversion circuit after being stepped up or stepped down to charge the battery pack 100. When the electric energy generated by the photovoltaic array 110 is insufficient to supply power to the grid 130 / external load 140, the electric energy stored in the battery pack 100 can be transmitted to the grid 130 / external load 140 through the DC / AC conversion circuit in the power converter 200. On the other hand, the energy storage system 150 can also receive power from the grid 130. The AC power output by the grid 130 is converted into DC power after passing through the DC / AC conversion circuit and transmitted to the battery pack 100 to charge the battery pack 100. Alternatively, the power converter 200 only includes a DC / AC conversion circuit, the battery pack 100 has a built-in DC / DC conversion circuit, and the battery pack 100 directly receives the DC power generated by the photovoltaic array 110. It can be understood that the energy storage system 150 can also be used in application scenarios such as wind power systems, and this application does not limit the application scenarios of the energy storage system 150.

[0120] Please refer to FIG2 , which is a schematic diagram of the structure of a battery pack provided in some embodiments of the present application.

[0121] The battery pack 100 includes a plurality of batteries 20. The plurality of batteries 20 are connected in series or in parallel. The batteries 20 may be secondary batteries, such as lithium ion secondary batteries, sodium ion secondary batteries, potassium ion secondary batteries, magnesium ion secondary batteries, zinc ion secondary batteries, aluminum ion secondary batteries, and the like.

[0122] An embodiment of the present application provides a battery comprising a housing, a pole core, a Mylar film, and a bottom support sheet. The pole core, Mylar film, and bottom support sheet are all housed within the housing, with the bottom surface of the pole core, the Mylar film, and the bottom support sheet stacked in sequence. The insulating porous membrane includes a plurality of through-holes, each with a pore size ranging from 1 nm to 100 nm. In the battery provided herein, the through-holes in the Mylar film can reduce the flow of dust shed from the pole piece between the bottom support sheet and the housing, reducing the possibility of a micro-short circuit between the bottom surface of the pole core and the housing. This reduces the possibility of housing corrosion, positive electrode carbonization, aluminum shell breakdown short circuit, and leakage, thereby improving the safety and reliability of the battery.

[0123] According to the eighth aspect, in one possible implementation, the bottom support sheet includes a plurality of openings, and the plurality of openings and the plurality of through-holes are arranged non-overlappingly. The positions of the plurality of openings and the plurality of through-holes are staggered to prevent the openings of the bottom support sheet and the through-holes of the Mylar film from being aligned along the same line, thereby extending the diffusion path of dust from the bottom surface of the electrode core to the housing, thereby reducing the possibility of a micro-short circuit between the bottom surface of the electrode core and the housing.

[0124] In another embodiment, the battery further includes an insulating porous membrane. Please refer to Figures 3 and 4. Figure 3 is a perspective exploded schematic diagram of a battery provided in one embodiment of the present application. Figure 4 is a perspective schematic diagram of a battery provided in one embodiment of the present application with part of the shell removed. The battery 20 includes a shell 21, a pole core 23, a Mylar membrane 24, a bottom support sheet 25, and a battery cover 28. The shell 21 is used to accommodate an electrolyte (not shown). The pole core 23, the Mylar membrane 24, and the bottom support sheet 25 are all housed in the shell 21. The shell 21 is an aluminum shell. It can be understood that the shell 21 can be a shell made of other conductive materials. The battery cover 28 is covered on the shell 21 to form a closed cavity with the shell 21.

[0125] The pole core 23 includes a positive electrode sheet and a negative electrode sheet. The positive electrode sheet and the negative electrode sheet can intercalate and deintercalate metal ions (such as lithium ions) to achieve energy storage and release. The positive electrode sheet and the negative electrode sheet are the main energy storage parts of the battery 20, which can reflect the energy density, cycle performance and safety performance of the battery 20. The electrolyte can be a transmission carrier for metal ions. The Mylar film 24 can wrap the pole core 23, that is, the Mylar film 24 covers the pole core 23 and is used to insulate and isolate the pole core 23 from the shell 21. The pole core 23, the Mylar film 24 and the bottom support sheet 25 are stacked in sequence along the first direction. The bottom support sheet 25 is used to support and support the pole core 23, and the bottom support sheet 25 is used to insulate and separate the pole core 23 from the shell 21. The pole core 23 is a pole core that can be formed by lamination or winding. The first direction can be the Z direction shown in Figure 3.

[0126] In some embodiments of the present application, please refer to FIG5 , which is a perspective schematic diagram of a housing provided in one embodiment of the present application. The housing 21 has a generally cubic structure. The housing 21 includes a bottom wall 216 and a plurality of side walls 217 connected to the bottom wall 216. The bottom wall 216 and the bottom support plate 25 are arranged opposite each other along a first direction. The plurality of side walls 217 include a first side wall 2171, a second side wall 2172, a third side wall 2173, and a fourth side wall 2174. The area of ​​the first side wall 2171 may be greater than the area of ​​the third side wall 2173. The first side wall 2171 and the second side wall 2172 are arranged opposite each other along a second direction, and the third side wall 2173 and the fourth side wall 2174 are arranged opposite each other along a third direction. The first direction is perpendicular to the second direction, the second direction is perpendicular to the third direction, and the first direction is perpendicular to the third direction. The area of ​​the first side wall 2171 may be equal to the area of ​​the second side wall 2172. The area of ​​the third sidewall 2173 can be equal to the area of ​​the fourth sidewall 2174. It is understood that the areas of the four sidewalls 217 can be equal or unequal. It is understood that this application does not limit the housing 21 to a cubic structure; the housing 21 can be a regular or irregular shape, such as a disc or a sphere. When the housing 21 is circular, the number of sidewalls 217 can be one.

[0127] Both the positive and negative electrodes are composed of granular materials and a binder. However, particles from the positive and negative electrodes can easily break off, forming dust that enters the electrolyte. This can cause a micro-short circuit between the electrode core and the battery casing, leading to safety risks such as casing corrosion, carbonization of the positive electrode, aluminum shell breakdown, short circuits, and electrolyte leakage.

[0128] Based on this, please refer to Figure 5. The battery 20 provided in the present application may also include an insulating coating 218 coated on the inner wall of the shell 21. The insulating coating 218 is used to form insulating protection on the inner wall of the shell 21 to reduce the possibility of a micro-short circuit between the shell 21 and the pole core 23 when dust in the pole core 23 falls into the shell 21, thereby reducing the possibility of shell corrosion, positive electrode carbonization, aluminum shell breakdown short circuit, and leakage, thereby improving the safety and reliability of the battery 20. Figure 5 exemplarily shows that the insulating coating 218 is coated on the surface of the second side wall 2172 facing the inner cavity of the shell 21. The shaded portion in Figure 5 is the insulating coating 218. If the thickness of the insulating coating 218 is too thin, its insulation performance may be poor. If the thickness of the insulating coating 218 is too thick, it will affect the energy density of the battery. Therefore, the thickness range of the insulating coating 218 is [30μm, 200μm], that is, the thickness of the insulating coating 218 is not less than 30μm and not greater than 200μm. For example, the thickness of the insulating coating 218 can be 30μm, 35μm, 40μm, 50μm, 55μm, 60μm, 65μm, 70μm, 75μm, 80μm, 85μm, 90μm, 95μm, 100μm, 150μm, 200μm, so as to have better insulation performance.

[0129] In some embodiments of the present application, as shown in FIG. 6 , which is a cross-sectional view taken along line I1 shown in FIG. 5 , the insulating coating 218 is coated on a side of the bottom wall 216 facing the inner cavity of the housing 21 .

[0130] Please refer to Figure 7, which is a schematic diagram of a battery used in an upright position. When the battery 20 is used in an upright position, one end of the housing 21 where the bottom wall 216 is located is in contact with or in contact with a support surface 300 for supporting the battery 20. The support surface 300 can be the ground, for example. When the battery 20 is placed in an upright position, dust tends to fall toward the bottom wall 216 due to gravity. However, since the insulating coating 218 is applied to the bottom wall 216, the dust is insulated from the surface of the bottom wall 216 facing the inner cavity of the housing 21 by the insulating coating 218, reducing the possibility of a micro-short circuit between the bottom wall 216 and the pole core 23 due to the dust.

[0131] In some embodiments of the present application, the insulating coating 218 can be applied to the surfaces of the first side wall 2171 and the second side wall 2172 facing the inner cavity of the housing 21. When the battery 20 is used in the first side placement scenario, as shown in FIG8 , which is a schematic diagram of the battery used in the first side placement scenario, the first side wall 2171 is in contact with the support surface 300 for supporting the battery 20. It can be understood that one of the first side wall 2171 and the second side wall 2172 is in contact with or in contact with the support surface 300 for supporting the battery 20. When the battery 20 is placed on its first side, dust tends to fall toward the first side wall 2171 or the second side wall 2172 due to gravity. However, since the insulating coating 218 is applied to the surfaces of the first side wall 2171 and the second side wall 2172 facing the inner cavity of the shell 21, the dust is insulated and isolated from the first side wall 2171 and the second side wall 2172 by the insulating coating 218, reducing the possibility of a micro-short circuit between the first side wall 2171, the second side wall 2172 and the pole core 23 due to the dust. Since the insulating coating 218 is applied to the inner walls of the first side wall 2171 and the second side wall 2172 facing the shell 21, when the battery 20 is placed on its side, either the first side wall 2171 or the second side wall 2172 can contact the support surface supporting the battery 20, facilitating the use of the battery 20.

[0132] In some embodiments of the present application, the insulating coating 218 is applied to the surfaces of the third and fourth side walls 2173 and 2174 facing the inner cavity of the housing 21. When the battery 20 is placed on its second side, as shown in FIG9 , which is a schematic diagram of the battery in this second side placement scenario, the fourth side wall 2174 contacts the support surface 300 for supporting the battery 20. It will be understood that one of the third and fourth side walls 2173 and 2174 contacts the support surface 300 for supporting the battery 20. When the battery 20 is placed on its second side, dust tends to fall toward the third or fourth side wall 2173 or 2174 due to gravity. However, since the insulating coating 218 is applied to the third and fourth side walls 2173 and 2174, the dust is insulated and isolated from the third or fourth side wall 2173 and 2174 by the insulating coating 218, reducing the possibility of micro-short circuits between the third and fourth side walls 2173 and 2174 and the electrode core 23 caused by the dust. Because both the third side wall 2173 and the fourth side wall 2174 are coated with the insulating coating 218, when the battery 20 is placed on its side, either the third side wall 2173 or the fourth side wall 2174 can contact the support surface of the battery 20, facilitating the use of the battery 20. It is understood that this application does not limit the thickness of the insulating coating 218. It is also understood that the location of the insulating coating 218 on the inner wall of the housing 21 is not limited; for example, the insulating coating 218 can be applied to the entire area or a portion of the inner wall of the housing 21.

[0133] It can be understood that the inner wall of the shell 21 includes a bottom wall, and the bottom supporting piece 25 is located between the pole core 23 and the bottom wall of the inner wall. The bottom wall of the inner wall is the surface of the bottom wall 216 facing the inner cavity of the shell 21.

[0134] It can be understood that the inner wall of the shell 21 includes a bottom wall and four side walls connected to the bottom wall, the bottom support plate 25 is located between the pole core 23 and the bottom wall, and the insulating coating 218 is coated on the side walls of the two opposite inner walls. The side walls of the inner wall are the surfaces of the side walls 217 facing the inner cavity of the shell 21.

[0135] The insulating coating 218 can be formed on the inner wall of the housing 21 by electrophoretic coating or inner wall spraying. The insulating coating 218 includes organic and / or inorganic materials. The organic materials include but are not limited to ultraviolet curing coating (UV) spray materials, polyethylene (PE) coating materials, polypropylene (PP) aluminum-plastic film, silicon coating, organic resin coatings of various proportions, etc. The inorganic materials include but are not limited to ceramics, magnesium oxide, aluminum oxide, water glass, phosphate, talc, etc.

[0136] The main material in the UV spray material / organic resin coating can be one or more of epoxy resin, acrylic resin, polyurethane resin, hydroxy acrylic resin and other multifunctional resins.

[0137] The auxiliary agent in the UV spray material / organic resin coating can be one or more of a photoinitiator, a reactive diluent, a flame retardant, a wetting agent, a leveling agent, a defoaming agent, and the like.

[0138] In some embodiments of the present application, forming the insulating coating 218 on the inner wall of the housing 21 of the battery 20 may include the following steps: pre-cleaning the battery 20, spraying an insulating coating on the inner wall of the housing 21, and then curing the coating to form the insulating coating 218 on the inner wall of the housing 21. The step of pre-cleaning the battery 20 includes performing surface cleaning on the inner wall of the housing 21, including but not limited to plasma cleaning, laser cleaning, water cleaning, and the like.

[0139] When laser cleaning is used to clean the inner surface of the housing 21, the laser cleaning depth is [5μm, 10μm], the laser cleaning power range is [500W, 2000W] (high power), and the laser cleaning speed is [5000mm / s, 15000mm / s] to achieve excellent cleaning results. It is understood that this application does not limit the specific values ​​of the laser cleaning depth, laser cleaning power, and laser cleaning speed when laser cleaning the housing 21.

[0140] When plasma cleaning is used to clean the inner wall of the shell 21, the plasma cleaning power range is [200W, 1500W], the plasma cleaning output frequency range is [20kHz, 40kHz], and the plasma cleaning heats the temperature of the shell 21 to [40°C, 80°C], that is, the temperature of the shell 21 is heated to not less than 40°C and not more than 80°C, to obtain an excellent cleaning effect. It is understood that this application does not limit the plasma cleaning power, plasma cleaning output frequency, and the temperature at which the shell 21 is heated during plasma cleaning of the shell 21. It is understood that this application does not limit the specific values ​​of the plasma cleaning power, plasma cleaning output frequency range, and the temperature at which the shell 21 is heated during plasma cleaning of the shell 21.

[0141] The distance of the insulating coating spraying depends on the size of the battery housing. The time range of the insulating coating spraying is [1 minute, 8 minutes]. It is understood that this application does not limit the time range of the insulating coating spraying, and the coating can be sprayed on the inner wall of the housing 21.

[0142] In some embodiments of the present application, please refer to FIG10 , which is a perspective diagram of a pole core provided in one embodiment of the present application. The pole core 23 includes a bottom surface 231, multiple side surfaces 233, and a top surface 235. The multiple side surfaces 233 are connected between the bottom surface 231 and the top surface 235. The bottom surface 231 and the top surface 235 are arranged opposite each other along a first direction. The multiple side surfaces 233 include a first side surface 2331, a second side surface 2332, a third side surface 2333 and a fourth side surface 2334. The first side surface 2331 and the second side surface 2332 are arranged opposite to each other along the second direction, and the third side surface 2333 and the fourth side surface 2334 are arranged opposite to each other along the third direction. The first side surface 2331 is connected to the bottom surface 231, the second side surface 2332 is connected to the bottom surface 231, the third side surface 2333 is connected to the bottom surface 231, and the fourth side surface 2334 is connected to the bottom surface 231. The Mylar film 24 wraps the first side surface 2331, the second side surface 2332, the third side surface 2333 and the fourth side surface 2334.

[0143] Please refer to Figures 10 and 11 in conjunction. Figure 11 is a side view of a battery provided in one embodiment of the present application with the casing removed. The Mylar film 24 wraps around the bottom surface 231, the side surface 233, and the top surface 235. In some embodiments of the present application, the Mylar film 24 wraps around the first side surface 2331, the second side surface 2332, the third side surface 2333, the fourth side surface 2334, and the top surface 235. It is understood that the Mylar film 24 can wrap around at least one of the first side surface 2331, the second side surface 2332, the third side surface 2333, and the fourth side surface 2334. For example, the Mylar film 24 can wrap around the first side surface 2331 and the second side surface 2332 but not the third side surface 2333 and the fourth side surface 2334.

[0144] Referring to FIG. 12 , FIG. 12 is a plan view of a Mylar film according to an embodiment of the present invention. The portion of the Mylar film 24 located on the bottom surface 231 includes a plurality of first openings 241 for circulating electrolyte. Region 2413 of the Mylar film 24 is attached to the bottom surface 231 .

[0145] Please refer to Figure 13, which is a schematic diagram of a three-dimensional exploded view of the Mylar film, the insulating porous film, and the bottom support sheet. The bottom support sheet 25 includes a second opening 251. The second opening 251 is used to circulate the electrolyte. In some embodiments of the present application, the position of the first opening 241 (as shown in Figure 12) is staggered with the position of the second opening 251 to prevent the first opening 241 and the second opening 251 from being arranged along the same straight line, thereby extending the diffusion path of dust from the bottom surface 231 of the pole core 23 to the shell 21, thereby reducing the possibility of a micro-short circuit between the bottom surface 231 and the shell 21.

[0146] The battery 20 also includes an insulating porous membrane 26, which is positioned between the Mylar film 24 and the bottom support sheet 25 in the first direction. The bottom surface 231, the Mylar film 24, the insulating porous membrane 26, and the bottom support sheet 25 are stacked in sequence along the first direction. The insulating porous membrane 26 is used to absorb dust. The insulating porous membrane 26 includes a plurality of through-holes 261, each of which has a smaller pore size than the first opening 241, and a smaller pore size than the second opening 251. The through-holes 261 in Figure 13 are for illustrative purposes only and do not represent the actual size of the through-holes 261 in actual use.

[0147] Through hole 261 allows for the flow of electrolyte. The aperture of through hole 261 is smaller than that of first opening 241, and smaller than that of second opening 251. Through hole 261 reduces the flow of dust between the Mylar film 24 and the bottom support sheet 25, reducing the possibility of a micro-short circuit between the electrode core 23 and the housing 21. This reduces the possibility of housing 21 corrosion, positive electrode carbonization, aluminum shell breakdown short circuit, and electrolyte leakage, thereby improving the safety and reliability of battery 20.

[0148] In some embodiments of the present application, the aperture range of the first opening 241 and the second opening 251 is [1mm, 5mm]. The aperture range of the first opening 241 and the second opening 251 is not less than 1mm and not greater than 5mm. For example, the aperture of the first opening 241 can be 1mm, 2mm, 3mm, 4mm and 5mm, and the aperture of the second opening 251 can be 1mm, 2mm, 3mm, 4mm and 5mm. The pore size range of the through hole 261 is [0.01μm, 50μm]. The pore size of the through hole 261 is not less than 0.01μm and not greater than 50μm. For example, the pore size of the through hole 261 can be 0.01μm, 0.03μm, 0.05μm, 0.07μm, 0.1μm, 0.3μm, 0.5μm, 0.7μm, 1μm, 3μm, 5μm, 7μm, 10μm, 13μm, 15μm, 17μm, or 20μm. For example, the particle size range of the dust is approximately [10μm, 20μm], and the aperture of the through hole 261 can be set at [0.01μm, 10μm]. The through hole 261 does not allow dust with a particle size greater than 10μm to pass through, which greatly reduces the flow of dust between the bottom surface 231 and the bottom wall 216, and greatly reduces the possibility of a micro short circuit between the pole core 23 and the shell 21.

[0149] The insulating porous membrane 26 can be made of a multilayer composite membrane, an organic / inorganic composite membrane, a nanofiber-coated membrane, an electrospun membrane, a cellulose-based membrane, or other materials. The thickness of the insulating porous membrane 26 ranges from 2 μm to 200 μm. The porosity of the insulating porous membrane 26 ranges from 10% to 90%. It should be understood that this application does not limit the thickness range or porosity range of the insulating porous membrane 26.

[0150] In some embodiments of the present application, the Mylar film 24, the insulating porous film 26, and the bottom support sheet 25 form an integrated composite structure. The Mylar film 24, the insulating porous film 26, and the bottom support sheet 25 can be formed into an integrated composite structure by hot pressing. The temperature range for hot pressing the Mylar film 24, the insulating porous film 26, and the bottom support sheet 25 is [100°C, 300°C]. It is understood that the present application is not limited to forming the integrated composite structure of the Mylar film 24, the insulating porous film 26, and the bottom support sheet 25 by hot pressing. The Mylar film 24, the insulating porous film 26, and the bottom support sheet 25 can also be formed into an integrated composite structure by other processes. It can be understood that the Mylar film 24, the insulating porous membrane 26, and the bottom support sheet 25 may not form an integrated composite structure. The Mylar film 24, the insulating porous membrane 26, and the bottom support sheet 25 may also be a separate structure, or the Mylar film 24 and the insulating porous membrane 26 are an integrated structure, or the insulating porous membrane 26 and the bottom support sheet 25 are an integrated structure.

[0151] In related technologies, the Mylar film is easily damaged at the connection between the bottom and side surfaces of the pole core due to the relatively large stress applied during bending, causing dust in the pole core to reach the shell through the damaged part of the Mylar film, forming a micro short circuit between the pole core and the shell through the damaged part.

[0152] The Mylar film 24 is located between the insulating porous film 26 and the pole core 23. The area covered by the Mylar film 24 on the bottom surface 231 is 2413 (as shown in Figure 12). The bottom surface 231 and the side surface 233 form a connection. In some embodiments of the present application, the bottom surface 231 intersects with the first side surface 2331 to form a first connection, and the bottom surface 231 intersects with the second side surface 2332 to form a second connection. The Mylar film 24 wraps the first connection and the second connection. The insulating porous film 26 extends from the bottom surface 231 to the first side surface 2331 and wraps the first connection. The insulating porous film 26 extends from the bottom surface 231 to the second side surface 2332 and wraps the second connection. Please refer to Figures 13 and 14 in combination. Figure 14 is a plan view of the bottom support sheet, Mylar film and insulating porous film provided in an embodiment of the present application when they are stacked together. The width of the insulating porous film 26 is roughly the same as the width of the bottom surface 231 in the third direction. The insulating porous membrane 26 extends in its longitudinal direction longer than the length of the bottom surface 231 in the second direction. The insulating porous membrane 26 covers the bottom surface 231, the first connection, and the second connection. Because the Mylar film 24 and the insulating porous membrane 26 are wrapped around the first and second connections, the insulating porous membrane 26 provides enhanced protection for the Mylar film 24 at the first and second connections, reducing the possibility of damage to the Mylar film 24 at the first and second connections, thereby reducing the possibility of micro-short circuits between the electrode core 23 and the housing 21.

[0153] In some embodiments of the present application, please refer to Figures 10 and 15. Figure 15 is a schematic diagram of a three-dimensional assembly of a battery with the battery housing and cover removed. The insulating porous membrane 26 covers the side of the Mylar film 24 facing away from the third side 2333. The insulating porous membrane 26 covers the side of the Mylar film 24 facing away from the third side 2333 to increase the area of ​​the Mylar film 24 covered by the insulating porous membrane 26 and improve the protection area of ​​the Mylar film 24 provided by the insulating porous membrane 26. The top surface 235 is connected to the end of the third side 2333 away from the bottom surface 231, and the top surface 235 is connected to the end of the fourth side 2334 away from the bottom surface 231. The top surface 235 and the bottom surface 231 are arranged opposite each other along a first direction. The pole core 23 also includes a pole tab 237 protruding from the top surface 235. The insulating porous membrane 26 covers the top surface 235 , thereby increasing the area of ​​the insulating porous membrane 26 covering the pole core 23 , reducing the flow of dust between the top surface 235 of the pole core 23 and the shell 21 , and further reducing the possibility of a micro short circuit between the pole core 23 and the shell 21 .

[0154] The insulating porous membrane 26 located on the top surface 235 is provided with an avoidance hole 267 (as shown in Figure 15) for passing the pole lug 237. The pole lug 237 is passed through the avoidance hole 267. The pole lug 237 is electrically connected to the battery cover 28 to output electrical energy from the battery 20 to the electrical device, or to input electrical energy into the battery 20. The pole lug 237 includes a positive pole lug and a negative pole lug. The positive pole lug is formed by extending the positive electrode sheet. The negative pole lug is formed by extending the negative electrode sheet. The number of avoidance holes 267 can be two, one avoidance hole 267 is passed through the positive pole lug, and one avoidance hole 267 is passed through the negative pole lug. The number of avoidance holes 267 can also be one. Both the positive pole lug and the negative pole lug are passed through the avoidance hole 267. Please refer to Figures 15 and 16 in combination. Figure 16 is a planar schematic diagram of the bottom support sheet, Mylar film and insulating porous membrane provided in an embodiment of the present application when they are stacked together. A first groove 2673 is recessed on one side edge of the insulating porous membrane 26, and a second groove 2675 is recessed on one side edge of the insulating porous membrane 26. The first groove 2673 and the second groove 2675 are located on the top surface 235, and the side wall of the first groove 2673 and the side wall of the second groove 2675 together form an avoidance hole 267 (as shown in Figure 15).

[0155] In related technologies, the Mylar film at the bottom corner structure of the pole core is easily damaged due to the relatively large stress it is subjected to during bending, causing dust in the pole core to reach the shell from the damaged part of the Mylar film at the bottom corner structure, forming a micro short circuit between the pole core and the shell through the damaged part.

[0156] Please refer to Figures 10 and 17 in conjunction. Figure 17 is a schematic perspective view of a partial structure of a battery provided in one embodiment of the present application. The electrode core 23 also includes a bottom corner structure 239 formed by a bottom surface 231 and two adjacent side surfaces 233. The Mylar film 24 wraps around the bottom corner structure 239. The battery 20 also includes multiple protective tapes 27, each of which wraps around a corresponding bottom corner structure 239 and is located on the side of the Mylar film 24 facing away from the electrode core 23. The protective tapes 27 are partially located between the bottom support sheet 25 and the insulating porous film 26. The protective tapes 27 wrap around the bottom corner structure 239. This strengthens the Mylar film 24 at the bottom corner structure 239, reduces the possibility of damage to the Mylar film 24 at the bottom corner structure 239, reduces the amount of dust flowing between the bottom corner structure 239 of the electrode core 23 and the housing 21, and further reduces the possibility of a micro-short circuit between the electrode core 23 and the housing 21.

[0157] For example, the bottom surface 231, the first side surface 2331, and the third side surface 2333 together form a bottom corner structure 239; the bottom surface 231, the first side surface 2331, and the fourth side surface 2334 together form a bottom corner structure 239; the bottom surface 231, the second side surface 2332, and the third side surface 2333 together form a bottom corner structure 239; and the bottom surface 231, the second side surface 2332, and the fourth side surface 2334 together form a bottom corner structure 239. It can be understood that the number of bottom corner structures 239 varies depending on the shape and structure of the pole core 23.

[0158] It can be understood that the inner wall of the shell 21 includes a bottom wall, the bottom supporting sheet 25 is located between the insulating porous membrane 26 and the bottom wall of the inner wall, and the bottom wall of the inner wall is the surface of the bottom wall 216 facing the inner cavity of the shell 21.

[0159] It can be understood that the inner wall of the shell 21 includes a bottom wall and four side walls connected to the bottom wall. The bottom support sheet 25 is located between the insulating porous membrane 26 and the bottom wall of the inner wall. The insulating coating 218 can be coated on the side walls of two opposite inner walls. The side walls of the inner wall are the surfaces of the side walls 217 facing the inner cavity of the shell 21.

[0160] Please refer to Figures 18 and 19. Figure 18 is a perspective schematic diagram of a battery cover provided in one embodiment of the present application, and Figure 19 is a partial cross-sectional view taken along line I2-I2 in Figure 18 provided in one embodiment of the present application. The battery cover 28 can be a one-piece structure or a separate structure. In some embodiments of the present application, the battery cover 28 includes a cover 281, an upper insulating plastic member 282, a lower insulating plastic member 283, and a terminal 285. The cover 281 includes a first surface and a second surface disposed opposite each other in a first direction. The first surface can be the upper surface 2811 shown in Figure 19, and the second surface can be the lower surface 2813 shown in Figure 19. The lower surface 2813 is located on the side of the cover 281 facing the bottom surface 231. The cover 281 can be a metal cover. It should be understood that the present application does not limit the material of the cover 281. The upper insulating plastic member 282 securely covers a portion of the upper surface 2811. The lower insulating plastic part 283 is located between the lower surface 2813 and the top surface 235 of the pole core 23, and the lower insulating plastic part 283 covers a portion of the lower surface 2813. The pole 285 is provided through the lower insulating plastic part 283, the cover plate 281, and the upper insulating plastic part 282, and the pole 285 is electrically connected to the pole core 23. The upper insulating plastic part 282 and the lower insulating plastic part 283 are used to electrically insulate the cover plate 281 and the pole 285. The pole 285 includes a positive pole and a negative pole. The positive pole is electrically connected to the positive terminal lug, and the negative pole is electrically connected to the negative terminal lug. The positive and negative poles are used to electrically connect to an external device to enable power transmission between the battery 20 and the external device.

[0161] The upper surface 2811 and the lower surface 2813 each include at least one surface pore. A portion of the upper insulating plastic part 282 is embedded in the surface pore of the upper surface 2811, and a portion of the lower insulating plastic part 283 is embedded in the surface pore of the lower surface 2813, so that the upper insulating plastic part 282, the cover plate 281, and the lower insulating plastic part 283 form an integrated composite structure. While improving the sealing performance of the battery cover plate 28, it can also simplify the structure of the battery cover plate 28 and facilitate the assembly of the battery cover plate 28 with other components. In addition, the upper surface 2811 where the cover plate 281 contacts the upper insulating plastic part 282 has at least one surface pore, and a portion of the upper insulating plastic part 282 is embedded in at least one surface pore of the upper surface 2811. In this way, the connection stability between the upper insulating plastic part 282 and the cover plate 281 is improved. The lower surface 2813 of the cover plate 281 in contact with the lower insulating plastic part 283 has at least one surface pore, and a portion of the lower insulating plastic part 283 is embedded in at least one surface pore of the lower surface 2813, thereby improving the connection stability between the lower insulating plastic part 283 and the cover plate 281.

[0162] It can be understood that one of the upper surface 2811 and the lower surface 2813 is provided with a surface pore, and a portion of the cover plate 281 is embedded in the surface pore.

[0163] In some embodiments of the present application, the surface pores are nanoscale pores, and the diameter of the nanoscale pores ranges from [10 nm to 500 nm]. These nanoscale pores can increase the contact area between the cover plate 281 and the upper insulating plastic member 282, and between the cover plate 281 and the lower insulating plastic member 283, thereby improving the connection strength between the cover plate 281 and the upper insulating plastic member 282, and between the cover plate 281 and the lower insulating plastic member 283. The width of the surface pores ranges from [0.05 mm to 1 mm]. In the first direction, the depth of the surface pores ranges from [0.1 mm to 3 mm]. The thickness of the cover plate 281 ranges from [0.1 mm to 9 mm].

[0164] The cover plate 281 is provided with a first pole through-hole 2817 that passes through the upper surface 2811 and the lower surface 2813. The first pole through-hole 2817 is used to pass through the pole 285. The surface pores are spaced apart from the periphery of the first pole through-hole 2817, that is, there is a distance between the surface pores and the outer periphery of the first pole through-hole 2817 to reduce the possibility of cracking of the hole wall of the first pole through-hole 2817 and causing cracking of the cover plate 281. The surface pores are spaced apart from the outer periphery of the cover plate 281 to reduce the possibility of cracking of the outer periphery of the cover plate 281 and causing cracking of the cover plate 281. The cover plate 281 also has an injection hole and a mounting hole. The injection hole is used to inject electrolyte. The mounting hole is used to install an explosion-proof valve.

[0165] In some embodiments of the present application, the upper insulating plastic component 282 is integrally injected into the surface pores of the upper surface 2811 of the cover plate 281 through integral injection molding, creating an anchoring effect to secure the upper insulating plastic component 282 to the cover plate 281. The lower insulating plastic component 283 is integrally injected into the surface pores of the lower surface 2813 of the cover plate 281 through integral injection molding, creating an anchoring effect to secure the lower insulating plastic component 283 to the cover plate 281. The upper insulating plastic component 282, the cover plate 281, and the lower insulating plastic component 283 form a unique, integrated, sealed structure, improving the sealing performance of the battery cover plate 28 while reducing the need for sealing structures.

[0166] The material of the upper insulating plastic member 282 and the lower insulating plastic member 283 is selected from polyethylene, polypropylene, polyacetal, polystyrene, modified polyethylene terephthalate, polybutylene terephthalate, polynaphthalate, polyphenylene sulfide, polyimide, polyamideimide, polyetherimide, polysulfone, polyethersulfone, polyetherketone, polyether magnesium, polycarbonate, polyamide, or acrylonitrile-butadiene-styrene copolymer. The material of the cover is selected from at least one of aluminum, titanium, aluminum alloy, titanium alloy, or stainless steel.

[0167] The material of the upper insulating plastic part 282 and the lower insulating plastic part 283 includes fillers, and the fillers include at least one of glass fiber, carbon fiber, carbon nanotube, carbon black, cement, and ceramic.

[0168] In some embodiments of the present application, the upper insulating plastic part 282 has a second pole through-hole 2821 for receiving the pole 285. The lower insulating plastic part 283 has a third pole through-hole 2831 for receiving the pole 285. The pole 285 is passed through the second pole through-hole 2821 and the third pole through-hole 2831.

[0169] In one possible implementation, as shown in FIG. 20 , which is a partial cross-sectional view taken along line I2-I2 of FIG. 18 , the upper insulating plastic member 282 further includes a body 2823 and an extension 2825 protruding from the body 2823 on the side facing the cover 281. The second pole through-hole 2821 extends through the body 2823 and the extension 2825. The body 2823 partially covers the upper surface 2811. The outer wall of the extension 2825 abuts against the inner wall of the first pole through-hole 2817. The extension 2825 extends into the first pole through-hole 2817 and is located between the inner wall of the first pole through-hole 2817 and the outer wall of the pole 285, thereby reducing the possibility of a gap between the upper insulating plastic member 282 and the cover 281.

[0170] Please refer to Figures 20, 21, and 22. Figure 21 is a perspective schematic diagram of the seal of the battery cover shown in Figure 20, and Figure 22 is a radial cross-sectional view of the seal shown in Figure 20. The battery cover 28 also includes a seal 287, which is disposed within the third terminal through-hole 2831 and the first terminal through-hole 2817. The seal 287 has a hollow structure, and the terminal 285 is disposed within the hollow structure of the seal 287. The seal 287 is used to achieve a sealed connection between the terminal 285, the lower insulating plastic component 283, and the cover 281, thereby reducing the entry of moisture, impurities, etc. into the interior of the battery 20.

[0171] The material of the seal 287 is selected from polyethylene, polypropylene, polyacetal, polystyrene, modified polyethylene terephthalate, polybutylene terephthalate, polynaphthalate, polyphenylene sulfide, polyimide, polyamideimide, polyetherimide, polysulfone, polyethersulfone, polyetherketone, polyether magnesium, polycarbonate, polyamide, acrylonitrile-butadiene-styrene copolymer, ceramic, and cement.

[0172] The material of the sealing member 287 includes fillers, and the fillers include glass fiber, carbon fiber, carbon nanotube, carbon black, cement, and ceramics.

[0173] In some possible implementations, the upper insulating plastic part 282 , the sealing part 287 , and the lower insulating plastic part 283 may be made of organic insulating materials or inorganic insulating materials, such as doping-optimized ceramic materials, doping-optimized PPS organic materials, glass, cement, and other materials.

[0174] As shown in FIG20 , in some embodiments of the present application, a radial cross-section of the seal 287 along the seal 287 generally presents a T-shaped stepped structure. The seal 287 includes a first sealing portion 2871 and a second sealing portion 2873 connected and arranged along the axial direction of the seal 287. The diameter of the first pole through-hole 2817 is smaller than the diameter of the third pole through-hole 2831. The diameter of the second pole through-hole 2821 is smaller than the diameter of the first pole through-hole 2817. The outer diameter of the first sealing portion 2871 is smaller than the outer diameter of the second sealing portion 2873. The first sealing portion 2871 is sequentially disposed through the first pole through-hole 2817 and the second pole through-hole 2821. The extension portion 2825 is located between the outer wall of the first sealing portion 2871 and the inner wall of the first pole through-hole 2817, and the outer wall of the first sealing portion 2871 is in contact with the inner wall of the second pole through-hole 2821. Second sealing portion 2873 is housed within third terminal through-hole 2831. Second sealing portion 2873 is located between the inner wall of third terminal through-hole 2831 and the outer wall of terminal 285. Upper and lower insulating plastic components 282 and 283 are integrally injection-molded with sealing component 287 to form a stepped structure. This prevents the gap between upper and lower insulating plastic components 282 and 283, and sealing component 287 from causing electrolyte crystallization and potentially leading to electrical conduction.

[0175] It can be understood that the aperture of the first pole through hole 2817 can be no smaller than the aperture of the third pole through hole 2831, and the aperture of the second pole through hole 2821 can be no smaller than the aperture of the first pole through hole 2817. For example, the apertures of the first pole through hole 2817, the second pole through hole 2821, and the third pole through hole 2831 can be the same, or the aperture of the first pole through hole 2817 can be larger than the aperture of the third pole through hole 2831, and the aperture of the second pole through hole 2821 can be larger than the aperture of the first pole through hole 2817.

[0176] It can be understood that the present application does not limit the structure of the sealing member 287 .

[0177] Referring to Figures 20, 21, and 22, the sealing member 287 further includes a first recessed portion 2876 recessed in the second sealing portion 2873 on the side facing the cover plate 281. The first recessed portion 2876 is configured to be fixedly connected to the cover plate 281. A portion of the cover plate 281 is fixedly embedded in the first recessed portion 2876. The first recessed portion 2876 is disposed along the outer periphery of the second sealing portion 2873, thereby giving the second sealing portion 2873 a stepped structure.

[0178] The cover plate 281 is partially fixed in the first recessed portion 2876 , thereby increasing the connection area between the cover plate 281 and the second sealing portion 2873 , reducing the possibility of a gap between the cover plate 281 and the second sealing portion 2873 , and improving the sealing and connection strength between the cover plate 281 and the second sealing portion 2873 .

[0179] The sealing member 287 also includes a second recessed portion 2877, which is configured to be securely connected to the lower insulating plastic member 283. The second recessed portion 2877 is recessed into the inner wall of the second sealing member 2873 facing the inner wall of the third pole through-hole 2831. A flange 2833 is formed on the inner wall of the third pole through-hole 2831 of the lower insulating plastic member 283, facing the second sealing member 2873 (as shown in FIG. 20 ). The flange 2833 is securely received within the second recessed portion 2877. Because the flange 2833 is securely received within the second recessed portion 2877, the connection area between the lower insulating plastic member 283 and the second sealing member 2873 is increased, the likelihood of a gap between the lower insulating plastic member 283 and the second sealing member 2873 is reduced, and the sealing and connection strength between the lower insulating plastic member 283 and the second sealing member 2873 are improved.

[0180] It is understood that the first recessed portion 2876 and the second recessed portion 2877 may be annular grooves or annular recesses extending along the circumference of the second sealing portion 2873, or may not extend along the circumference of the second sealing portion 2873. The first recessed portion 2876 and the second recessed portion 2877 may be omitted. The number of first recessed portions 2876 may be two or more to increase the connection area between the second sealing portion 2873 and the lower insulating plastic part 283 of the cover plate 281, thereby improving the connection stability and sealing performance between the sealing member 287 and the lower insulating plastic part 283. The number of second recessed portions 2877 may be two or more to increase the connection area between the second sealing portion 2873 and the lower insulating plastic part 283 of the cover plate 281, thereby improving the connection stability and sealing performance between the sealing member 287 and the lower insulating plastic part 283.

[0181] As shown in Figure 22, in some embodiments of the present application, the length D of the second sealing portion 2873 extending along the radial direction R of the second sealing portion 2873 is [50 μm, 600 μm], thereby increasing the contact area between the second sealing portion 2873 and the cover plate 281. The height H of the second sealing portion 2873 in the first direction Z is [50 μm, 2000 μm], thereby increasing the strength of the second sealing portion 2873. It should be understood that this application does not limit the length of the second sealing portion 2873 extending along the radial direction R of the second sealing portion 2873, nor does it limit the height H of the second sealing portion 2873 in the first direction Z.

[0182] In one possible implementation, as shown in FIG23 , which is a partial cross-sectional view of an embodiment of the present application taken along line I2-I2 in FIG18 , an extension portion 2825 is disposed through first pole through-hole 2817. A first sealing portion 2871 is disposed through second pole through-hole 2821 and abuts against the inner wall of second pole through-hole 2821. Extension portion 2825 is located between the inner wall of first pole through-hole 2817 and the outer wall of first sealing portion 2871. The end surface of extension portion 2825 facing away from body 2823 abuts against second sealing portion 2873.

[0183] In one possible implementation, as shown in Figures 24, 25, and 26, Figure 24 is a partial cross-sectional view taken along line I2-I2 of Figure 18 according to one embodiment of the present application. Figure 25 is a perspective schematic view of the seal of the battery cover shown in Figure 24. Figure 26 is a partial cross-sectional view of the assembled cover, lower insulating plastic component, and seal according to one embodiment of the present application. The second sealing portion 2873 has a stepped structure. The second recessed portion 2877 is recessed on a side of the second sealing portion 2873 facing the cover 281 in the first direction. The second recessed portion 2877 is disposed along the outer periphery of the second sealing portion 2873 facing away from the hollow structure of the seal 287. The flange 2833 is fixedly received within the second recessed portion 2877. The side of the second sealing portion 2873 facing the cover 281 is in contact with a portion of the lower surface 2813, and the outer wall of the first sealing portion 2871 is in contact with the outer wall of the first terminal through-hole 2817. The end surface of the extension portion 2825 away from the main body 2823 is in contact with the first sealing portion 2871 and the end surface away from the second sealing portion 2873 is in contact with each other.

[0184] In one possible implementation, as shown in Figure 27, Figure 27 is a partial cross-sectional view of the cover plate, lower insulating plastic part, and seal provided in an embodiment of the present application assembled together. The seal 287 omits the first recessed portion, and the second recessed portion 2877 is located on the peripheral wall of the second sealing portion 2873 away from the hollow structure, and the flange 2833 is fixed in the second recessed portion 2877.

[0185] In one possible implementation, as shown in FIG28 , which is a partial cross-sectional view of the assembled cover plate, lower insulating plastic component, and seal provided in one embodiment of the present application, the seal 287 omits the first recessed portion. The second recessed portion 2877 is located at the end of the second sealing portion 2873 facing away from the cover plate 281 in the first direction. The flange 2833 is provided at the end of the third pole through hole 2831 facing away from the cover plate 281 in the first direction. The flange 2833 is fixed and clamped to the second recessed portion 2877.

[0186] In one possible implementation, as shown in FIG29 , which is a partial cross-sectional view of the assembled cover plate, upper insulating plastic member, and seal according to one embodiment of the present application, the seal member 287 further includes a third recessed portion 2878 recessed in a first direction on a surface of the first sealing portion 2871 that is distal from the second sealing portion 2873. The third recessed portion 2878 extends through the outer peripheral wall of the first sealing portion 2871 that faces away from the hollow structure. The upper insulating plastic member 282 has a protruding recessed portion 2826 on a surface facing the cover plate 281. The recessed portion 2826 is at least partially fixedly received within the third recessed portion 2878. This increases the connection area between the upper insulating plastic member 282 and the first sealing portion 2871, reduces the possibility of a gap between the upper insulating plastic member 282 and the first sealing portion 2871, and improves the sealing and connection strength between the upper insulating plastic member 282 and the first sealing portion 2871.

[0187] In a possible implementation, as shown in FIG30 , FIG30 is a partial cross-sectional view of the cover plate, the upper insulating plastic component, and the sealing component provided in an embodiment of the present application assembled together, and the third recessed portion 2878 is a groove.

[0188] In one possible implementation, as shown in Figure 31, Figure 31 is a partial cross-sectional view of the cover plate, upper insulating plastic part, and seal provided in an embodiment of the present application assembled together, and the third recessed portion 2878 passes through the inner peripheral wall of the hollow structure of the first sealing portion 2871 facing the seal 287.

[0189] It is understandable that the second pole through hole 2821 may not penetrate the extension portion 2825 , and the extension portion 2825 only needs to be connected to the first sealing portion 2871 .

[0190] It can be understood that the extension portion 2825 of the upper insulating plastic component 282 can be omitted.

[0191] Please refer to Figure 32, which is a schematic diagram of a battery cover provided with an insulating protective film according to one embodiment of the present application. An insulating protective film 29 is also provided on the side of the battery cover 28 facing the electrode core. The insulating protective film 29 is used to insulate the electrolyte from the battery cover 28, preventing corrosion caused by contact between the electrolyte and the battery cover 28, thereby improving battery safety. In some embodiments of the present application, the insulating protective film 29 is positioned away from the explosion-proof valve mounting hole 2893 and the injection hole 2895.

[0192] The insulating protective film 29 can be made of organic material or inorganic material. The organic material is not limited to polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyimide or polyethylene terephthalate, and the inorganic material is not limited to ceramic, magnesium oxide, aluminum oxide, water glass, phosphate, talc and other materials.

[0193] The insulating protective film 29 can be prepared by any of the following methods: vacuum coating, electroplating, chemical coating, spraying, brushing, scraping or dipping.

[0194] The thickness of the insulating protective film 29 can be [10 μm, 200 μm]. It is understood that the insulating protective film 29 can be designed for the integrated battery cover 28. When the battery cover 28 is a split design, the insulating protective film 29 also covers the side of the battery cover 28 facing the pole core.

[0195] It should be understood that expressions such as "include" and "may include" used in this application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this application, terms such as "include" and / or "have" may be interpreted as indicating specific characteristics, numbers, operations, constituent elements, components, or combinations thereof, but may not be interpreted as excluding the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0196] In addition, in this application, the expression "and / or" includes any and all combinations of the associated listed words. For example, the expression "A and / or B" may include A, may include B, or may include both A and B.

[0197] In this application, expressions including ordinal numbers such as "first" and "second" may modify various elements. However, such elements are not limited by the above expressions. For example, the above expressions do not limit the order and / or importance of the elements. The above expressions are only used to distinguish one element from other elements. For example, a first user device and a second user device indicate different user devices, even though the first user device and the second user device are both user devices. Similarly, without departing from the scope of this application, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

[0198] When a component is referred to as being "connected" or "accessed" to another component, it should be understood that the component is not only directly connected to or accessed to the other component, but also that another component may exist between the component and the other component. On the other hand, when a component is referred to as being "directly connected to" or "directly accessed" to another component, it should be understood that no component exists between them.

[0199] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A battery, characterized in that: The battery comprises a shell, a core, a Mylar film, an insulating porous film and a bottom support sheet, wherein the core, the Mylar film, the insulating porous film and the bottom support sheet are all accommodated in the shell; The bottom surface of the pole core, the Mylar film, the insulating porous film and the bottom support sheet are stacked in sequence, and the insulating porous film includes a plurality of through holes.

2. The battery according to claim 1, characterized in that The Mylar film located on the bottom surface includes a plurality of first openings, the bottom support sheet includes a plurality of second openings, the aperture of the through hole is smaller than the aperture of the first opening, and the aperture of the through hole is smaller than the aperture of the second opening.

3. The battery according to claim 2, characterized in that The plurality of first openings and the plurality of second openings are arranged not to overlap.

4. The battery according to claim 1, characterized in that The aperture range of the through hole is [0.01 μm-50 μm].

5. The battery according to claim 1, characterized in that The pole core also includes a side surface, and the insulating porous film covers the connection between the side surface and the bottom surface.

6. The battery according to claim 5, characterized in that The pole core further includes a top surface and a pole ear, the top surface is arranged opposite to the bottom surface, the side surface is connected between the bottom surface and the top surface, and the pole ear is arranged on the top surface and protrudes from the top surface; The Mylar film covers the side surface and the top surface; The insulating porous film covers the surface of the Mylar film away from the side surface and the top surface; The insulating porous membrane located on the top surface is provided with an avoidance hole, and the pole tab is passed through the avoidance hole.

7. The battery according to claim 1, characterized in that The pole core further comprises two adjacently connected side surfaces, the two side surfaces and the bottom surface together form a bottom angle structure, and the Mylar film wraps the bottom angle structure; The battery further comprises a protective tape, which covers the bottom corner structure and is located on a side of the Mylar film away from the pole core, and the protective tape is partially located between the bottom support sheet and the insulating porous film.

8. The battery according to claim 1, characterized in that The battery further comprises a battery cover plate, which is arranged on the shell, and the pole core comprises a top surface, which is arranged opposite to the bottom surface, and an insulating protective film is arranged on the side of the battery cover plate facing the top surface of the pole core.

9. The battery according to claim 1, characterized in that The battery further comprises a battery cover plate, which is covered on the housing, and the battery cover plate, the pole core, the insulating porous membrane and the bottom support sheet are arranged in sequence. The battery cover includes a cover, an upper insulating plastic part, a lower insulating plastic part and a pole: The cover plate comprises a first surface and a second surface which are arranged opposite to each other, the second surface is arranged on a side of the cover plate facing the bottom surface, and the cover plate is provided with a first pole through hole which passes through the first surface and the second surface. The upper insulating plastic part at least partially covers the first surface, and the upper insulating plastic part is provided with a second pole through hole; The lower insulating plastic part is located between the second surface and the pole core, the lower insulating plastic part at least partially covers the second surface, and the lower insulating plastic part is provided with a third pole through hole; The pole is inserted into the third pole through hole, the first pole through hole and the second pole through hole, and the pole is electrically connected to the pole core.

10. The battery according to claim 9, characterized in that The first surface includes at least one surface pore; the upper insulating plastic part is partially embedded in the surface pore of the first surface; and / or the second surface includes at least one surface pore, and the lower insulating plastic part is partially embedded in the surface pore of the second surface.

11. The battery according to claim 10, characterized in that There is a distance between the surface pore and the outer periphery of the first pole through hole, and there is a distance between the surface pore and the outer periphery of the cover plate.

12. The battery according to claim 10, characterized in that The diameter range of the surface pores is [10 nm, 500 nm].

13. The battery according to claim 9, characterized in that The battery cover plate further includes a sealing member, and the sealing member is located between the inner wall of the first pole through hole and the outer wall of the pole.

14. The battery according to claim 13, characterized in that The aperture of the third pole through hole is larger than the aperture of the second pole through hole. The seal includes a first sealing portion and a second sealing portion which are connected to each other, wherein the outer diameter of the first sealing portion is smaller than the outer diameter of the second sealing portion, and the first sealing portion is at least partially located between the inner wall of the first pole through hole and the outer wall of the pole; the second sealing portion is located between the inner wall of the third pole through hole and the outer wall of the pole.

15. The battery according to claim 14, characterized in that The upper insulating plastic part also includes a body and an extension portion protruding from the body toward the cover plate, the second pole through hole passes through the body, the body covers at least part of the first surface, and the extension portion is located between the inner wall of the first pole through hole and the outer wall of the pole.

16. The battery according to claim 15, characterized in that The first sealing portion is partially located between the inner wall of the first pole through hole and the outer wall of the pole, and the rest of the first sealing portion is passed through the second pole through hole; the extension portion is located between the inner wall of the second pole through hole and the outer wall of the first sealing portion; or, the end surface of the extension portion away from the body is in contact with an end of the first sealing portion away from the second sealing portion.

17. The battery according to claim 14, characterized in that The sealing member further comprises a first recessed portion, which is recessed on a side of the second sealing portion facing the cover plate, and a portion of the cover plate is fixed in the first recessed portion.

18. The battery according to claim 14, characterized in that The seal also includes a second recessed portion, which is recessed in the outer peripheral wall of the hollow structure of the second seal away from the seal; the inner wall of the third pole through hole of the lower insulating plastic part forms a flange toward the seal, and the flange is embedded in the second recessed portion.

19. The battery according to claim 14, characterized in that The sealing member further comprises a third recessed portion, which is recessed in the end surface of the first sealing member away from the second sealing member; an embedding portion is provided on a surface of the upper insulating plastic member facing the cover plate, and the embedding portion is fixedly received in the recessed portion.

20. The battery according to claim 1, characterized in that An insulating coating is provided on the inner wall of the shell facing the pole core.

21. The battery according to claim 20, characterized in that The inner wall comprises a bottom wall, and the bottom supporting sheet is located between the insulating porous membrane and the bottom wall.

22. The battery according to claim 20, characterized in that The inner wall comprises a bottom wall and four side walls connected to the bottom wall, the bottom supporting sheet is located between the insulating porous membrane and the bottom wall, and the insulating coating is coated on two opposite side walls.

23. A battery pack, characterized in that: The battery pack comprises a plurality of batteries as described in any one of claims 1 to 22, and the plurality of batteries are connected in series or in parallel.

24. An energy storage system, characterized in that: The energy storage system includes the battery pack and power converter described in claim 23 above, wherein the power converter is used to convert the AC power output by an external AC power source into DC power and output it to the battery pack, and / or the power converter is used to convert the DC power output by the battery pack into AC power and output it to a load or a power grid.

25. A battery, characterized in that: The battery comprises a shell, a core, a Mylar film and a bottom support sheet, wherein the core, the Mylar film and the bottom support sheet are all accommodated in the shell; The bottom surface of the pole core, the Mylar film and the bottom support sheet are stacked in sequence, and the insulating porous film includes a plurality of through holes. The pore size range is [1nm-100nm].

26. The battery according to claim 25, characterized in that The bottom support sheet includes a plurality of openings, and the plurality of openings and the plurality of through holes are arranged in a non-overlapping manner.

Images