CN217768478U - Battery cell, battery, power consumption device and winding equipment - Google Patents

Abstract

The application discloses a battery monomer, a battery, an electric device and winding equipment, wherein the battery monomer comprises an electrode assembly and a support piece, the electrode assembly is formed by sequentially laminating a first pole piece, an isolation film and a second pole piece and winding the first pole piece, the electrode assembly is provided with a winding center hole, the support piece is arranged in the winding center hole, and the support piece is provided with a first end; the first end is connected with the isolation membrane. According to the embodiment of the application, the supporting piece can provide supporting force for the electrode assembly to resist the collapse and deformation of the electrode assembly, so that the problem of reduction of the performance of a battery is solved, and the service life of the battery is effectively prolonged.

Description

Battery cell, battery, power consumption device and winding equipment

Technical Field

The application belongs to the technical field of batteries, and particularly relates to a battery monomer, a battery, an electric device and winding equipment.

Background

The lithium ion battery is a rechargeable battery with excellent performance, and has the characteristics of high voltage, high capacity, low consumption, small volume, small internal resistance, multiple cycle times and the like, so that the lithium ion battery is widely applied to the fields of aerospace, traffic communication and the like.

Generally, a battery cell of a lithium ion battery is formed by winding an electrode assembly including an anode electrode, a cathode electrode, and a separator interposed therebetween, but in the current battery structure, the cycle performance of the battery is degraded to cause insufficient safety along with repeated charge and discharge processes.

Disclosure of Invention

The embodiment of the application provides a battery monomer, battery, power consumption device and coiling equipment, can effectively increase the security of battery.

In one aspect, an embodiment of the present application provides a battery cell, including: an electrode assembly formed by sequentially laminating a first pole piece, a separation film and a second pole piece and winding along a winding direction, wherein the electrode assembly is provided with a winding center hole; a support member disposed at the winding center hole, the support member having a first end; wherein the first end is connected with the isolation membrane.

The embodiment of the application has the advantages that the supporting effect is generated on the electrode assembly through the supporting piece, so that the battery can keep a more stable shape in the charging and discharging process, and the safety of the battery is further ensured.

Optionally, the first end is wound in lamination with the separator.

With the above structure, the support member and the electrode assembly are integrated, and the relative position of the support member and the electrode assembly can be maintained.

Alternatively, the first end overlaps or is spaced apart from the starting end of the separator in the winding direction.

By adopting the structure, the support piece is completely or partially wrapped by the isolation film, and the support piece can be isolated from the first pole piece and the second pole piece.

Optionally, the support further includes a second end, the second end is disposed away from the first end, and the second end overlaps with or is spaced apart from the starting end of the first pole piece in the winding direction.

By adopting the structure, the second end of the supporting piece is at least separated from the first pole piece, so that the influence of the supporting piece on the charge and discharge process of the electrode assembly can be avoided.

Optionally, in the winding direction, a minimum distance between the starting end and the second end of the first pole piece is smaller than a minimum distance between the starting end and the second end of the second pole piece.

By adopting the structure, the starting end of the second pole piece does not exceed the starting end of the first pole piece, so that the electrode assembly has better charge and discharge performance.

Optionally, the width of the support is smaller than the width of the first and second pole pieces.

With the above structure, the support member is not larger than the electrode assembly in the width direction, so that the battery cell can be fitted to the case.

Optionally, the length of the support member in the winding direction is 15mm to 50mm.

With the above-described structure, the support member may have more or less turns in the winding direction, thereby providing a more suitable supporting force to the electrode assembly.

Optionally, the material of the support comprises an elastic material, and the elastic modulus of the elastic material is 0.8-4GPa.

By adopting the structure, the supporting piece has the capability of elastic deformation, can generate corresponding elastic deformation when the pole piece deforms, provides better supporting force for the pole piece, and reduces the inward collapse deformation of the pole piece.

Optionally, at least one through hole is provided on the support.

By adopting the structure, the support piece has better compressibility, the weight of the support piece is reduced, and the influence of the support piece on the electrode assembly in the charging and discharging process can be reduced.

In another aspect, an embodiment of the present application provides a battery, including: a battery cell as above; and the box body is accommodated in the box body.

The battery of this application embodiment adopts as above the battery monomer including support piece, can improve battery performance, promotes the security and the life-span of battery.

On the other hand, the embodiment of the present application provides an electric device, including: the battery cell as described above, for providing electrical energy.

The electric device of the embodiment of the application adopts the battery cell comprising the support member as described above, so that the usability of the electric device can be improved.

In still another aspect, an embodiment of the present application provides a winding apparatus configured to wind an electrode assembly of a battery cell as described above, the electrode assembly being formed by sequentially stacking a first pole piece, a separator, and a second pole piece and winding in a winding direction, the electrode assembly having a winding center hole, a support member disposed in the winding center hole, the support member having a first end connected to the separator, and a support member, the winding apparatus including: a support member sticking mechanism configured to stick the support member to the separation film; a winding mechanism configured to wind the electrode assembly and the support in a winding direction.

The winding equipment of the embodiment of the application can be used for pasting the supporting piece on the isolating membrane, then winding the supporting piece and the electrode assembly together, and ensuring the winding quality of the supporting piece and the electrode assembly together by adjusting the flatness of the isolating membrane in the process.

According to the embodiment of the application, the support piece is arranged in the winding center hole formed by sequentially stacking and winding the first pole piece, the isolating membrane and the second pole piece in the winding direction of the electrode assembly, the support piece is provided with the first end connected with the isolating membrane, and the support piece and the electrode assembly are better combined, so that the support force is provided for the pole pieces, the pole pieces are prevented from collapsing and deforming, the problem of reduction of battery performance caused by further improvement is solved, and the service life and the safety of a battery are effectively prolonged.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

FIG. 1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

FIG. 2 shows a schematic structural diagram of a battery of some embodiments of the present application;

fig. 3 is a schematic view of a battery cell according to some embodiments of the present application;

fig. 4 shows an exemplary radial cross-sectional view of the battery cell of fig. 3;

reference numerals:

1. an electrode assembly; 10. winding the central hole; 11. a first pole piece; 12. a second pole piece; 13. an isolation film; 2. a support member; 201. a first end; 202. a second end; 3. a housing; 31. an end cap; 311. an electrode terminal; 32. a housing;

1000. a vehicle; 100. a battery; 110. a box body; 111. a first tank portion; 112. a second tank portion; 200. a controller; 300. a motor.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are merely used to more clearly illustrate the technical solutions of the present application, and therefore are only examples, and the protection scope of the present application is not limited thereby.

It is to be noted that technical terms or scientific terms used in the embodiments of the present application should be taken as a general meaning understood by those skilled in the art to which the embodiments of the present application belong, unless otherwise specified.

In the description of the embodiments of the present application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom" are used "

The references to "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., are based on the orientation or positional relationship shown in the drawings and are intended only to facilitate the description of the embodiments and to simplify the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the embodiments of the present application.

Furthermore, the technical terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. In the description of the embodiments of the present application, "a plurality" means two or more unless specifically defined otherwise.

In the description of the embodiments of the present application, unless otherwise explicitly specified or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrated; mechanical connection or electrical connection is also possible; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the embodiments of the present application can be understood by those of ordinary skill in the art according to specific situations.

In the description of the embodiments of the present application, unless otherwise explicitly specified or limited, a first feature "on" or "under" a second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "above," and "over" a second feature may be directly on or obliquely above the second feature, or simply mean that the first feature is at a higher level than the second feature. A first feature "under," "beneath," and "under" a second feature may be directly under or obliquely under the second feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In this application, the battery cell may include a lithium ion secondary battery cell, a lithium ion primary battery cell, a lithium sulfur battery cell, a sodium lithium ion battery cell, a sodium ion battery cell, or a magnesium ion battery cell, and the embodiment of this application does not limit this.

The battery cell comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive electrode piece, a negative electrode piece and a separation film arranged between the positive electrode piece and the negative electrode piece. The positive pole piece comprises a positive current collector and a positive active substance layer, and the positive active substance layer is coated on the surface of the positive current collector; the positive current collector comprises a positive current collecting part and a positive electrode lug connected to the positive current collecting part, wherein the positive current collecting part is coated with a positive active substance layer, and the positive electrode lug is not coated with the positive active substance layer. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, the positive electrode active material layer includes a positive electrode active material, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative pole piece includes negative current collector and negative active substance layer, and the negative active substance layer coats in the surface of negative current collector, and the negative current collector includes negative current collection portion and connects in the negative pole utmost point ear of negative current collection portion, and the coating of negative current collection portion has the negative active substance layer, and the negative pole utmost point ear does not coat the negative active substance layer. The material of the negative electrode current collector may be copper, the negative electrode active material layer includes a negative electrode active material, and the negative electrode active material may be carbon, silicon, or the like.

As known to those skilled in the art, a battery cell operates by relying primarily on the movement of metal ions between a positive and a negative pole piece. In the charging and discharging process, metal ions are inserted and extracted back and forth between the positive pole piece and the negative pole piece: during charging, metal ions are extracted from the positive electrode and are inserted into the negative electrode through the electrolyte; the opposite is true during discharging. The isolating membrane is mainly used for separating a positive pole piece and a negative pole piece of the battery, preventing the two pole pieces from being in contact and short circuit, and simultaneously ensuring that electrolyte ions can freely pass through the isolating membrane to form a charge-discharge loop. The material of the spacer may be polypropylene (PP) or Polyethylene (PE).

However, in the battery cell configured as above, the inventor has noticed that, since the pole piece material may undergo a chemical reaction of inserting and removing metal ions during charging and discharging, the lattice parameter may increase and decrease, and thus expansion and contraction of the pole piece may be caused, and stress release generated during the process may cause inward contraction and deformation of the pole piece, further causing adverse phenomena such as distortion, collapse, fracture, and the like, thereby affecting the battery performance. In the existing cell winding process, although a support structure such as a central needle is arranged at the center of an electrode assembly, the central needle is of a solid structure, cannot adapt to stress change of a pole piece, cannot provide a good support effect, and meanwhile, the central needle increases the volume of a battery and reduces the usability of the battery.

In view of this, the present application provides a technical solution, in which the support member is disposed in a central hole formed by sequentially stacking and winding the first pole piece, the isolation film and the second pole piece in the winding direction of the electrode assembly, and the support member has a first end connected to the isolation film, so that the support member and the electrode assembly are better combined, thereby providing a supporting force for the pole pieces, resisting collapse and deformation of the pole pieces, further improving the problem of performance reduction of the battery caused by the collapse and deformation of the pole pieces, and effectively prolonging the service life and safety of the battery.

The technical scheme described in the embodiment of the application is suitable for a single battery, a battery adopting the single battery, an electric device powered by the single battery, an electrode assembly for winding the single battery and winding equipment for a supporting piece.

The electric device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool and the like. The vehicle can be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extended vehicle and the like; spacecraft include aircraft, rockets, space shuttles, and spacecraft, among others; electric toys include stationary or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric airplane toys, and the like; the electric power tools include metal cutting electric power tools, grinding electric power tools, assembly electric power tools, and electric power tools for railways, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, electric impact drills, concrete vibrators, and electric planers. The embodiment of the present application does not specifically limit the above power utilization device.

It should be understood that the technical solutions described in the embodiments of the present application are not limited to be applied to the electric devices described above, but for simplicity of description, the following embodiments are all described by taking the vehicle 1000 as an example.

As shown in fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present application. The vehicle 1000 may be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile may be a pure electric automobile, a hybrid electric automobile, or an extended range automobile, etc. The battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000.

Since the battery cell refers to the smallest unit constituting a battery module or a battery pack, a plurality of battery cells may be connected in series and/or in parallel via the electrode terminal 311 to be applied to various applications. The battery 100 mentioned in the present application may include one battery cell or may include a plurality of battery cells.

In order to meet different power usage requirements, a plurality of battery cells may be provided in the battery 100 provided inside the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, and for example, the battery 100 may serve as an operation power source of the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to supply power to the motor 300, for example, for starting, navigation, and operational power requirements while the vehicle 1000 is traveling. In some embodiments of the present application, the battery 100 may be used not only as an operating power source of the vehicle 1000, but also as a driving power source of the vehicle 1000, instead of or in part of fuel or natural gas, to provide driving power for the vehicle 1000.

Fig. 2 shows a schematic diagram of the structure of the battery 100 according to some embodiments of the present application. As shown in fig. 4, the battery 100 includes a case 110 and a plurality of battery cells accommodated in the case 110.

The box body 110 may be a single cuboid, a cylinder, a sphere, or other simple three-dimensional structure, or may be a complex three-dimensional structure formed by combining cuboid, cylinder, or sphere, which is not limited in the embodiment of the present application. The material of the box body 110 may be an alloy material such as an aluminum alloy, an iron alloy, or the like, or a polymer material such as a polycarbonate, a polyisocyanurate foam, or a composite material such as a glass fiber and an epoxy resin, which is not limited in this embodiment of the application.

The case 110 is used to house the battery 100, and the case 110 may have various structures. In some embodiments, the case 110 may include a first case portion 111 and a second case portion 112, the first case portion 111 and the second case portion 112 cover each other, and the first case portion 111 and the second case portion 112 together define a receiving space for receiving the battery 100. The second casing part 112 may be a hollow structure with one open end, the first casing part 111 is a plate-shaped structure, and the first casing part 111 covers the open side of the second casing part 112 to form the casing 110 with an accommodating space; the first casing portion 111 and the second casing portion 112 may be hollow structures with one side open, and the open side of the first casing portion 111 covers the open side of the second casing portion 112 to form the casing 110 having the accommodating space. Of course, the first casing portion 111 and the second casing portion 112 may be in various shapes, such as a cylinder, a rectangular parallelepiped, and the like.

In order to improve the sealing performance after the first casing portion 111 and the second casing portion 112 are connected, a sealing member, such as a sealant or a gasket, may be provided between the first casing portion 111 and the second casing portion 112.

One battery cell may be provided in the case 110, or a plurality of battery cells may be provided. If the number of the battery monomers is multiple, the multiple battery monomers can be connected in series or in parallel or in series-parallel, and the series-parallel refers to that the multiple battery monomers are connected in series or in parallel. The plurality of battery cells may be directly connected in series or in parallel or in series-parallel, and the whole body formed by the plurality of battery cells is accommodated in the case 110; of course, a plurality of battery cells may be connected in series or in parallel or in series-parallel to form the battery 100, and a plurality of batteries 100 may be connected in series or in parallel or in series-parallel to form a whole and accommodated in the case 110. The plurality of battery cells in the battery 100 may be electrically connected to each other through a bus member, so as to realize parallel connection, series connection, or parallel-serial connection of the plurality of battery cells in the battery 100.

Fig. 3 is a schematic diagram of a battery cell according to some embodiments of the present application. As shown in fig. 3, the outer case 3 of the battery cell includes an end cap 31 and a case 32.

The end cap 31 is a member that covers an opening of the case 32 to isolate the internal environment of the battery cell from the external environment. Without limitation, the shape of the end cap 31 may be adapted to the shape of the housing 32 to fit the housing 32. Alternatively, the end cap 31 may be made of a material (e.g., an aluminum alloy) having a certain hardness and strength, so that the end cap 31 is not easily deformed when being extruded and collided, and thus the battery cell may have a higher structural strength and safety performance may be improved. The end cap 31 may be provided with functional components such as the electrode terminal 311. The electrode terminal 311 may be used to be electrically connected with the electrode assembly 1 for outputting or inputting electric energy of the battery cell. In some embodiments, the end cap 31 may further include a pressure relief mechanism for relieving the internal pressure when the internal pressure or temperature of the battery cell reaches a threshold value. The material of the end cap 31 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this embodiment. In some embodiments, insulation may also be provided on the inside of the end cap 31, which may be used to isolate the electrical connection components within the housing 32 from the end cap 31 to reduce the risk of short circuits. Illustratively, the insulator may be plastic, rubber, or the like.

The case 32 is an assembly for fitting the end cap 31 to form an internal environment of the battery cell, wherein the formed internal environment may be used to house the electrode assembly 1, an electrolyte (not shown in the drawings), and other components. The housing 32 and the end cap 31 may be separate components, and an opening may be provided on the housing 32, and the opening may be covered by the end cap 31 to form an internal environment of the battery cell. Without limitation, the end cap 31 and the housing 32 may be integrated, and specifically, the end cap 31 and the housing 32 may form a common connecting surface before other components are inserted into the housing, and when it is necessary to seal the interior of the housing 32, the end cap 31 covers the housing 32. The housing 32 may be a variety of shapes and sizes, such as rectangular parallelepiped, cylindrical, hexagonal prism, etc. Specifically, the shape of the case 32 may be determined according to the specific shape and size of the electrode assembly 1. The material of the housing 32 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this embodiment.

As shown in fig. 3, in the present embodiment, the battery cell is formed in a cylindrical body, and the electrode assembly 1 is disposed inside the case 3. In an alternative embodiment, the electrode assembly 1 comprises a first pole piece 11, a separator 13 and a second pole piece 12 stacked in sequence along the winding direction, the electrode assembly 1 having a winding central hole 10 to provide the support 2.

The isolation film 13 is disposed between the first pole piece 11 and the second pole piece 12, the first pole piece 11 is located inside the second pole piece 12, and the second pole piece 12 surrounds the first pole piece 11. Therefore, the first pole piece 11 is a positive pole piece, and the second pole piece 12 is a negative pole piece, so as to avoid the phenomenon of metal precipitation during the charging and discharging process.

Fig. 4 shows a radial cross-sectional schematic view of an exemplary battery cell of fig. 3. As shown in fig. 4, the support 2 is disposed in the winding center hole 10, wherein the separator 13 protrudes in the winding direction with respect to the first pole piece 11 and is wound in layers with the support 2.

That is, the support member 2 is formed in a spiral-like shape in a radial cross section, and is wound from the first end 201 located at the innermost side to the second end 202 located at the outermost side in the winding direction, and the electrode assembly 1 is wound continuously from the second end 202 of the support member 2 so as to be formed in a positional relationship in which they are arranged in order in the winding direction. Therefore, the support 2 is located at the center of the electrode assembly 1, and can provide a supporting stress directed from the inside of the battery cell to the outside for the electrode assembly 1, thereby preventing the first pole piece 11 and the second pole piece 12 from collapsing to the center during charging and discharging.

In order to distribute the support member 2 and the electrode assembly 1 in succession during the winding process, the separation film 13 is connected to the first end 201 of the support member 2 and attached to the surface of the support member 2, so as to integrate the support member 2 and the electrode assembly 1 and maintain the relative positions of the support member 2 and the electrode assembly 1. Also, the separation film 13 may be attached to both the inside and the outside of the supporter 2, thereby separating the supporter 2 from the electrode assembly 1 wound on the outside thereof.

In an alternative embodiment, the first end 201 of the support member 2 overlaps or is spaced apart from the starting end of the separator 13 in the winding direction. That is, the isolation film 13 is adhered to the support 2 from the first end 201 of the support 2 located at the innermost side of the winding, thereby completely wrapping the support 2; it may be adhered to the middle of the winding of the supporter 2 so as to partially wrap the supporter 2. In the present embodiment, the isolation film 13 completely covers the support 2, so that at least one isolation film 13 is present between the support 2 and the first pole piece 11. Alternatively, the starting end of the isolation diaphragm 13 may be located at other positions of the support 2, for example, a quarter turn from the first end 201, so as to isolate the support 2 from the pole piece.

In another alternative embodiment, the second end 202 of the support 2 overlaps or is spaced apart from the starting end of the first pole piece 11 in the winding direction. Since the isolation film 13 is wrapped around the support 2, the second end 202 extends inside the isolation film 13 during the winding process of the support 2, and since the first pole piece 11 is located at the innermost side of the electrode assembly 1 and is isolated from the second pole piece 12 by the isolation film 13, the second end 202 of the support 2 may still contact with the first pole piece 11. The second end 202 of the support member 2 is at least spaced apart from the first pole piece 11, so that the support member 2 can be prevented from affecting the charging and discharging processes of the electrode assembly 1.

In yet another alternative embodiment, the minimum distance between the starting end of the first pole piece 11 and the second end 202 of the support 2 in the winding direction is smaller than the minimum distance between the starting end of the second pole piece 12 and the second end 202 of the support 2. That is, the starting end of the second pole piece 12 does not exceed the starting end of the first pole piece 11 in the winding direction, thereby enabling the electrode assembly 1 to have a better metal ion exchange effect during charging and discharging.

Wherein, in order to provide a supporting stress to the electrode assembly 1, the material of the support member 2 includes an elastic material. Under the condition that forms into the elastic component, support piece 2 has elastic deformation's ability to can produce corresponding elastic deformation when the pole piece deformation, for the pole piece provides the better holding power of adaptability, reduce the pole piece to inside deformation that collapses. Moreover, since the support member 2 is disposed inside the single battery cell, the elastic material of the support member 2 should have the property of resisting the corrosion of the electrolyte, and therefore, the material of the support member 2 is a polymer material. In the present embodiment, the material of the supporting member 2 is compatible with the material of the isolation film 13, and both are PP composite materials. Alternatively, the supporting member 2 may be made of other materials, such as Polyethylene (PE), polyester resin (PET) or other film materials.

In order to make the material of the support 2 more suitable for the current use scenario, the elastic material should be made to have an elastic modulus of 0.8-4GPa in the selection of the material of the support 2. When the elastic modulus of the supporting member 2 is within this range, the supporting member 2 can provide a certain supporting force for the electrode assembly 1, which plays a certain role in reducing the deformation of the pole piece and improving the performance of the battery cell. However, it is preferable that the support 2 has an elastic modulus of 2 to 4GPa in consideration of the size of the support 2 and the production feasibility, and the supporting effect of the support 2 can be further improved.

In an alternative embodiment, the support 2 is provided with at least one through hole (not shown in the figures). The arrangement of the through holes can enable the supporting piece 2 to have better compressibility, reduce the weight of the supporting piece 2, and simultaneously reduce the influence of the supporting piece 2 on the electrode assembly 1 in the charging and discharging process, so that more accommodating spaces for accommodating electrode reaction substances are formed inside the battery cell. Preferably, the porosity of the support 2 may be 15% -95%. Since different elastic materials have different properties, in the case of selecting different elastic materials to form the supporting member 2, the porosity of the supporting member 2 will also have different values, which is determined according to the elastic modulus of the supporting member 2, and the application is not limited herein.

It is contemplated that, in order to simplify the manufacturing process of the battery cell provided in the present application, so that the support member 2 can be adapted to the winding technology of the electrode assembly 1 of the existing cylindrical battery cell, the winding radius of the support member 2 wound on the outermost side should be adapted to the winding radius of the first pole piece 11 wound on the innermost side. That is, in order that the support member 2 may be applied to an existing battery cell, the winding outer diameter of the support member 2 should be equal to the winding radius of the first pole piece 11 located at the innermost side of the electrode assembly 1 in winding.

Whereas the number of windings of the support 2 can be varied, in case the outer diameter of the windings of the support 2 is known. In order to ensure that the support member 2 can provide uniform supporting force to the electrode assembly 1 in various directions, the number of winding turns should be not less than one. However, it is preferable that the number of winding turns be 1.5 or more turns in consideration of the spiral shape of the supporter 2 to provide a better supporting force to the electrode assembly 1. For example, in the present embodiment, the number of windings of the support member 2 in the winding direction is one, and this number of windings can be increased by narrowing the winding interval per one winding of the support member 2 while keeping the winding outer diameter of the support member 2 constant.

In an alternative embodiment, the length of the support 2 in the direction of winding is 15mm to 50mm. In order to allow the support member 2 to have an elastic modulus within a predetermined range, the support member 2 needs to have a certain thickness. And, since the winding outer diameter of the support 2 is known, it is possible to obtain an upper limit of the number of winding turns of the support 2 accordingly, and further obtain the length of the support 2 in the winding direction. Therefore, in order to form the supporting member 2 into a predetermined structure, the length of the supporting member 2 is determined by combining the elastic material of the supporting member 2 and the thickness of the supporting member 2.

In an alternative embodiment, the first pole piece 11 and the second pole piece 12 have the same width, and the width of the support 2 is smaller than the width of the first pole piece 11 and the second pole piece 12. That is, since the support 2 is disposed at the center of the electrode assembly 1, the width thereof, i.e., the size in the height direction of the battery cell, must not be greater than the electrode assembly 1, thereby being able to fit the case 3 of the battery cell. Alternatively, the width of the support 2 may be approximately equal to 70-95% of the width of the first or second pole piece, which may be a dimension depending on the particular production situation.

In the present embodiment, the support member 2 is formed in a sheet shape, which has a greater production workability while saving materials. It is contemplated that the support member 2 may have other arrangements, such as a plurality of spiral-like arc pieces spaced apart to provide a corresponding support effect. Alternatively, the support 2 may be formed in a bar shape, and the present application is not limited thereto.

To sum up, the technical scheme provided by the present application, the support member 2 is disposed in the winding center hole 10 formed by sequentially stacking and winding the first pole piece 11, the isolation film 13 and the second pole piece 12 in the winding direction of the electrode assembly 1, and the support member 2 has the first end 201 connected to the isolation film 13, so that the support member 2 is better combined with the electrode assembly 11, thereby providing a supporting force for the pole pieces, resisting the pole pieces from collapsing and deforming, further improving the problem of battery performance reduction caused by the collapse, and effectively prolonging the service life and safety of the battery

A winding apparatus for winding the electrode assembly 1 of the battery cell and the support 2 will be described below.

From the above description, it is conceivable that the support 2 should be first adhered to the separation film 13 and then the support 2 should be wound together with the electrode assembly 1, thereby realizing a structure of supporting the electrode assembly 1 by the support 2. Accordingly, the present application provides a winding apparatus including a support member attaching mechanism and a winding mechanism. The support member attaching mechanism is configured to attach the support member 2 to the separator 13, and the winding mechanism is configured to wind the electrode assembly 1 and the support member 2 in the winding direction.

Here, at the support member attaching mechanism, first, the separator 13 is placed on the roll tape to fix one end of the separator 13, and the support member 2 is attached to the separator 13 by the support member attaching means. Thereafter, since the separator 13 of the adhesive support 2 is positioned at the innermost side of the winding of the electrode assembly 1, it is necessary to completely spread the separator 13 of a desired length of the electrode assembly 1 and store the portion of the separator not requiring the adhesive support 2 in the separator storage part. Then, the isolation film 13 passes through the tension control component and the snake-shaped entanglement component, so that the tension of the isolation film 13 is adjusted, and the flatness of the isolation film 13 adhered with the support member 2 is further ensured when the isolation film enters the winding mechanism.

The winding equipment can adjust the length of the isolating membrane 13 for adhering the support member 2, the precision control can reach 0.01m, and the winding quality of the support member 2 and the electrode assembly 1 which are wound together can be ensured while the adhering process of the support member 2 is simplified.

Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; these modifications and substitutions do not depart from the spirit of the embodiments of the present application, and they should be construed as being included in the scope of the claims and description of the present application. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. The present application is not intended to be limited to the particular embodiments disclosed herein but is to cover all embodiments that may fall within the scope of the appended claims.

Claims (12)

1. A battery cell, comprising:

an electrode assembly formed by sequentially laminating a first pole piece, a separation film and a second pole piece and winding along a winding direction, wherein the electrode assembly is provided with a winding center hole;

a support disposed at the winding center hole, the support having a first end;

wherein the first end is connected to the isolation diaphragm.

2. The battery cell of claim 1, wherein the first end is wound in stack with the separator film.

3. The battery cell according to claim 2, wherein the first end overlaps or is spaced apart from a starting end of the separation film in the winding direction.

4. The battery cell as recited in claim 1, wherein the support member further comprises a second end disposed away from the first end, the second end overlapping or spaced apart from the starting end of the first pole piece in the winding direction.

5. The battery cell according to claim 4, wherein a minimum distance between the starting end of the first pole piece and the second end in the winding direction is smaller than a minimum distance between the starting end of the second pole piece and the second end.

6. The battery cell of claim 1, wherein the support member has a width that is less than a width of the first and second pole pieces.

7. The battery cell according to claim 6, wherein the length of the support member in the winding direction is 15mm to 50mm.

8. The battery cell as recited in claim 1, wherein the support comprises an elastic material having a modulus of elasticity of 0.8-4GPa.

9. The battery cell as recited in claim 1 wherein the support member is provided with at least one through hole.

10. A battery, comprising:

a battery cell according to any one of claims 1 to 9; and

and the plurality of battery monomers are accommodated in the box body.

11. An electric device, comprising:

a battery cell as claimed in any one of claims 1 to 9 for providing electrical energy.

12. A winding apparatus configured to wind an electrode assembly of the battery cell according to any one of claims 1 to 9, the electrode assembly being formed by sequentially stacking a first pole piece, a separator, and a second pole piece and winding them in a winding direction, the electrode assembly having a winding center hole, the support being disposed in the winding center hole, the support having a first end connected to the separator, the winding apparatus comprising:

a support member sticking mechanism configured to stick the support member to the release film;

a winding mechanism configured to wind the electrode assembly and the support in the winding direction.

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