CN213717028U

CN213717028U - Coiling electric core and anti-needling soft package battery comprising same

Info

Publication number: CN213717028U
Application number: CN202022448927.5U
Authority: CN
Inventors: 不公告发明人
Original assignee: Evergrande New Energy Technology Shenzhen Co Ltd
Current assignee: Evergrande New Energy Technology Shenzhen Co Ltd
Priority date: 2020-10-29
Filing date: 2020-10-29
Publication date: 2021-07-16
Anticipated expiration: 2030-10-29

Abstract

The utility model provides a winding battery cell and a needling-prevention soft package battery comprising the same, wherein the winding battery cell comprises a positive plate, a first diaphragm, a negative plate and a second diaphragm which are arranged in a stacking way, and the winding battery cell is of a winding body structure after winding; the surface of the positive plate is divided into a positive coating area, a positive lug area and a smooth foil area; the surface of the negative plate is divided into a negative coating area and a negative lug area; the positive coating area, the first diaphragm, the negative coating area and the second diaphragm are overlapped; the whole electric core periphery of positive plate's plain foil district cladding forms electric core outer lane, and positive ear district forms anodal ear, and negative ear district forms the negative pole ear, anodal ear with the negative pole ear is located the both ends of electric core respectively. The utility model discloses after the battery is pierced by the needle, can conduct electric core electric current everywhere and heat fast, effectively improve the acupuncture security performance of lithium cell.

Description

Coiling electric core and anti-needling soft package battery comprising same

Technical Field

The utility model belongs to the technical field of lithium ion battery, relate to coiling electric core, especially relate to a coiling electric core and including its prevent acupuncture laminate polymer battery.

Background

The lithium ion battery has the advantages of high working voltage, high energy density, long cycle life, long storage time and the like, and is more and more widely applied to the fields of consumer electronics, energy storage, power automobiles and the like, wherein the power automobiles have the strictest requirements on the safety performance of the lithium ion battery. At present, lithium ion batteries used by power automobiles have various potential safety hazards, wherein safety problems caused by short circuits are most obvious and frequent. In the actual use process, under the actions of metal foreign body puncture, weight impact, external force extrusion and high-temperature heating above 130 ℃, burrs are punctured and the diaphragm is thermally shrunk due to direct contact of the positive and negative pole pieces or pole piece fracture, so that the internal short circuit of the battery is caused, and safety accidents such as fire or explosion are caused.

At present, prevent the acupuncture, the common method of the short circuit that striking and extrusion caused, be at electric core inner and outer lane increase vest, prolong the mass flow body and the length of diaphragm of just, negative pole piece head and tail end promptly, because the mass flow body is pure metal material, have good electric conductivity and heat conductivility, when electric core takes place the short circuit, the vest can share most electric current, the heat that produces of quick conduction pole piece short circuit department simultaneously reduces battery temperature to avoid causing electric core thermal runaway because of the short circuit. In addition, the thermal shrinkage of the separator caused by the fact that the battery cell is heated at a high temperature or short circuit occurs inside the battery cell is reduced by coating the ceramic separator, so that the short circuit or the short circuit expansion of the positive and negative electrode plates is avoided or slowed down.

However, the waistcoat and the coating pole piece have different strength and tension, and the increase of the waistcoat has the problems of reducing the production efficiency and the product quality; the cost and technical requirements of ceramic coating are high, the uniformity and consistency of the coating thickness are difficult to control, and the ceramic powder is very easy to absorb water, so that the ceramic powder is difficult to widely apply. In addition, a flame retardant is added in the electrolyte formula to inhibit the reaction activity of the electrolyte, but the flame retardant can reduce the conductivity of the electrolyte and further influence the performance of the battery. The short circuit safety hidden trouble of the lithium battery cannot be completely and effectively eliminated.

CN204857884U discloses positive, negative pole piece coiling lamination formula lithium cell electricity core, including positive terminal, negative terminal and lithium cell shell, positive terminal is installed to lithium cell shell one end, and the positive terminal inboard is installed the positive plate of lamination formula multilayer, and the terminal an organic whole of coiling of positive plate is formed with positive ear, and the lithium cell shell other end is installed negative terminal, the lamination formula multilayer negative pole piece is installed to the extreme inboard, the terminal an organic whole of coiling of negative pole piece is formed with the negative ear. This electric core preparation is convenient, is formed with utmost point ear in the electric core, has bigger electric current area of conducting, but it has the diaphragm thermal contraction and the problem of the just, negative pole short circuit that leads to, causes the danger of catching fire or explosion.

CN103762387A discloses a preparation method of a winding type polymer lithium battery and the winding type polymer lithium battery, the winding type polymer lithium battery comprises a packaging shell and a winding body assembled in the packaging shell, the winding body comprises a diaphragm, a positive plate and a negative plate, the positive plate and the negative plate are separated by the diaphragm and wound for a certain number of turns, and the ending parts of the positive plate and the negative plate are respectively welded with a positive lug and a negative lug. The battery can adjust the spot welding mode and position of the lug. However, the positive electrode tab and the negative electrode tab are not of a full tab structure, so that the conduction of electrons and heat is not facilitated, and the problem of short circuit of the positive electrode and the negative electrode caused by thermal contraction of the diaphragm exists.

CN107732318A discloses a winding core of a safety lithium ion battery and a lithium ion battery containing the winding core of the safety lithium ion battery. The battery rolls up the core and is in by including negative pole piece and positive plate and range upon range of setting diaphragm between negative pole piece and the positive plate is convoluteed and is formed, and the outside electrode slice that the battery rolled up the core does the negative pole piece, and the blank end that is no negative pole active layer at the negative pole piece end blank end electricity is connected with negative pole utmost point ear blank end inboard the face towards the battery roll core that has combined the temperature resistant insulating layer on the surface. According to the invention, the mechanical strength of the battery roll core is improved, the heat outward diffusion capability is improved, and the risk of explosion of the battery core is avoided by changing the position of the negative pole tab at the tail end of the negative pole piece and additionally arranging the heat-resistant insulating layer. However, the structure is complicated due to the additional arrangement of the temperature-resistant insulating layer, and the manufacturing difficulty of the battery is increased.

The existing winding battery cell has the problems of complex structure and unfavorable electron and heat conduction, so that the problem of how to avoid the short circuit of a positive electrode and a negative electrode caused by the thermal contraction of a diaphragm under the condition of ensuring that the winding battery cell has good electric conductivity is urgently solved at present.

SUMMERY OF THE UTILITY MODEL

Not enough to prior art exists, the utility model aims to provide a coiling electricity core, and include its prevent acupuncture laminate polymer battery, through anodal ear district and negative pole ear district coiling forming's anodal ear and negative pole ear respectively, make anodal ear and negative pole ear have full utmost point ear structure, and, the whole electric core periphery of positive plate's smooth foil district cladding forms electric core outer lane, the electric current and the heat conduction of battery core accelerate, accelerate the electric quantity and the heat release of lithium cell, avoid diaphragm thermal contraction (inside short circuit heat production and arouse) and lead to the inside short circuit of electric core, effectively improve the acupuncture security performance of lithium cell.

To achieve the purpose, the utility model adopts the following technical proposal:

in a first aspect, the utility model provides a winding battery cell, including positive plate, first diaphragm, negative plate and the second diaphragm that stack up the setting, be the winding body structure after coiling, the positive plate surface divide into anodal coating district, anodal ear district and smooth foil district, the width one side in anodal coating district is the smooth foil district, and length one side is anodal ear district, anodal ear district with the smooth foil district be L shape and distribute; the surface of the negative plate is divided into a negative coating area and a negative lug area, and one side of the length of the negative coating area is the negative lug area;

the positive coating region, the first separator, the negative coating region, and the second separator coincide; the whole electric core periphery of positive plate's smooth foil district cladding forms electric core outer lane, positive pole ear district form anodal ear, negative pole ear district form the negative pole ear, anodal ear with the negative pole ear is located the both ends of electric core respectively.

Anodal ear and negative pole ear be the full utmost point ear structure of different sides, anodal ear and negative pole ear are located the both ends symmetry setting of coiling electric core, directly will just, the inner and outer lane of negative pole piece switches on and links to each other, after the battery is pierced by the acupuncture, can conduct electric core current everywhere and heat fast, avoid local overflowing the heat production and lead to electric core thermal runaway's problem to the acupuncture security performance of coiling electric core has been promoted.

The utility model discloses an outer lane is the smooth foil district of the anodal thick liquids of uncoated, has avoided the processing procedure yield problem by the vest structural design of extension just, the negative current collector, moreover, compares the conventional outer lane and ends with the diaphragm of extension, also has better electric current and heat conduction effect, more is favorable to improving the acupuncture security performance of coiling electric core.

It is known to those skilled in the art that the coating in the positive coating region should be coated with positive slurry, the coating in the negative coating region should be coated with negative slurry, and the optical foil region is an empty foil.

As a preferred embodiment of the present invention, the length of the first separator is greater than the length of the negative electrode coating region by 5 to 10mm, for example, the length of the first separator is greater than the length of the negative electrode coating region by 5.0mm, 5.5mm, 6.0mm, 6.5mm, 7.0mm, 7.5mm, 8.0mm, 8.5mm, 9.0mm, 9.5mm, or 10mm, but the present invention is not limited to the recited values, and other values not recited in the range of the values are also applicable.

The width of the first separator is 1 to 2mm greater than the width of the negative electrode coating region, for example, the width of the first separator is 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, or 2.0mm greater than the width of the negative electrode coating region, but is not limited to the recited values, and other values not recited in the range of values are also applicable.

The length of the negative electrode coating region is 5 to 10mm greater than the length of the positive electrode coating region, for example, the length of the negative electrode coating region is 5.0mm, 5.5mm, 6.0mm, 6.5mm, 7.0mm, 7.5mm, 8.0mm, 8.5mm, 9.0mm, 9.5mm or 10mm greater than the length of the positive electrode coating region, but not limited to the recited values, and other values not recited in the range of values are also applicable.

The width of the negative electrode coating region is 1 to 2mm greater than the width of the positive electrode coating region, for example, the width of the negative electrode coating region is 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm or 2.0mm greater than the width of the positive electrode coating region, but not limited to the recited values, and other values not recited in the range of values are equally applicable.

The first and second diaphragms have equal planar profile dimensions.

The distance between the edge of the positive electrode tab and the edge close to the first separator is 13 to 17mm, for example, 13mm, 13.5mm, 14.0mm, 14.5mm, 15.0mm, 15.5mm, 16.0mm, 16.5mm or 17mm, but the distance is not limited to the values listed, and other values not listed in the range of the values are also applicable.

The distance between the edge of the negative electrode tab and the edge close to the first separator is 13 to 17mm, for example, 13mm, 13.5mm, 14.0mm, 14.5mm, 15.0mm, 15.5mm, 16.0mm, 16.5mm or 17mm, but is not limited to the above-mentioned values, and other values not shown in the above-mentioned range are also applicable.

In a preferred embodiment of the present invention, the thickness of the positive electrode sheet in which the optical foil region is located is 12 to 16 μm, for example, 12 μm, 12.5 μm, 13.0 μm, 13.5 μm, 14.0 μm, 14.5 μm, 15.0 μm, 15.5 μm, or 16.0 μm, but the thickness is not limited to the values listed, and other values not listed in the range of the values are also applicable.

As a preferred technical scheme of the utility model, first diaphragm include the substrate, the upper surface and the lower surface of substrate all are provided with the composite bed.

The utility model discloses set up the composite bed and be used for increasing the mechanical strength of diaphragm to and isolated diaphragm is heated, thereby avoid electric core under the high temperature heating condition or inside diaphragm thermal contraction when taking place the short circuit and heat up, thereby avoid or slow down just, the short circuit or the short circuit of negative pole piece enlarge the ization.

It should be noted that the present invention does not have specific requirements and specific limitations on the material and structure of the substrate, for example, the substrate is a three-layer PP/PE/PP composite film, a double-layer PP/ceramic, a double-layer PP/PE, a single-layer PP or a single-layer PE.

The first diaphragm has the same structure as the second diaphragm.

The base material comprises a PP layer, a PE layer and a PP layer which are sequentially stacked.

The utility model discloses a base film adopts three-layer PP PE PP complex film, compares individual layer polyolefin membrane, and it is good not only to have a thermal stability, and mechanical strength is also high, effectively avoids the diaphragm to be heated and warp.

As a preferred embodiment of the present invention, the composite layer includes a boehmite layer and a conductive polymer layer disposed on the surface and in the pores of the boehmite layer.

The utility model discloses utilize high temperature resistant conducting polymer modified boehmite layer, have higher heat stability. Compared with ceramic coatings, the coating has the advantages of small granularity, large specific surface, uniform particles, low water absorption, high heat-resisting temperature and the like. And conductive polymers are arranged on the surface and in the pores of the diaphragm, so that the boehmite layer, the polymer layer and the base film form an organic whole, the thermal stability and the mechanical strength of the composite base film are further improved, the contact between the positive electrode and the negative electrode is effectively blocked, and the needling safety performance of the lithium battery is improved.

As a preferred technical scheme of the utility model, the material of conducting polymer layer include polyquinoline, poly-p-phenylene or poly-p-phenylene sulfide.

It should be noted that the material of the conductive polymer layer in the present invention may include not only polyquinoline, poly-p-phenylene or poly-p-phenylene sulfide, but also polyquinoline derivative, poly-p-phenylene derivative or poly-p-phenylene sulfide derivative.

In a second aspect, the utility model provides a prevent acupuncture laminate polymer battery, prevent acupuncture laminate polymer battery include foretell coiling electric core.

Exemplarily, the utility model provides a preparation method of above-mentioned coiling electricity core, preparation method specifically includes:

coating positive electrode slurry on an aluminum foil to form a positive electrode coating area of a positive electrode plate, wherein uncoated areas are a positive electrode lug area and a smooth foil area respectively, and preparing to obtain the positive electrode plate; coating the copper foil with negative electrode slurry to form a negative electrode coating area of the negative electrode sheet, wherein the uncoated area is a negative electrode lug area, and preparing to obtain the negative electrode sheet;

coating boehmite layers on the upper surface and the lower surface of the diaphragm base material, and coating a conductive polymer on the boehmite layers in a spraying mode to prepare a first diaphragm and a second diaphragm;

(III) range upon range of positive plate, first diaphragm, negative pole piece and the second diaphragm that sets up, wherein, coincidence in first diaphragm, anodal coating district, second diaphragm and negative coating district, negative pole ear district and anodal ear position in different sides, preparation obtain after the coiling shaping coiling electric core, wherein, the whole electric core periphery of positive plate's smooth foil district cladding forms electric core outer lane, and anodal ear district forms anodal ear, and the negative pole ear district forms the negative pole ear, anodal ear and negative pole ear are located the both ends of electric core respectively.

Compared with the prior art, the beneficial effects of the utility model are that:

the utility model discloses a positive pole ear, negative pole ear are the full utmost point ear structure of different sides, and directly switch on the interior outer lane of just, negative pole piece through it and link to each other. After the battery is pierced by the needle, can conduct electric current and heat everywhere with electric core more fast, avoid local overflowing the heat production and lead to electric core thermal runaway to the security performance has been promoted. In addition, the whole electric core periphery of smooth foil district cladding through positive plate forms electric core outer lane, avoids vest structural design's processing procedure yield problem, compares conventional outer lane and ends with the diaphragm of extension, has better electric current and heat conduction effect, further improves the acupuncture security performance of lithium cell.

Drawings

Fig. 1 is a schematic top view illustrating a winding ending in a winding cell according to an embodiment of the present invention;

fig. 2 is a schematic front view of a winding ending in a winding cell according to an embodiment of the present invention;

fig. 3 is a schematic plan view of a positive plate in a wound electrical core according to an embodiment of the present invention;

fig. 4 is a schematic plan view of a negative electrode sheet in a wound electrical core according to an embodiment of the present invention.

Wherein, 1-positive coating region; 2-a light foil area; 3-positive ear region; 4-negative pole coating area; 5-negative ear region; 6-a first membrane; 7-negative pole piece; 8-a second membrane; 9-positive plate.

Detailed Description

It is to be understood that in the description of the present invention, the terms "central," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for the purpose of convenience and simplicity of description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be construed as limiting the present invention.

It should be noted that, unless explicitly stated or limited otherwise, the terms "disposed," "connected" and "connected" in the description of the present invention are to be construed broadly, and may for example be fixedly connected, detachably connected or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The technical solution of the present invention is further explained by the following embodiments with reference to the accompanying drawings.

In a specific embodiment, the present invention provides a winding electric core, as shown in fig. 1 and fig. 2, the winding electric core is a winding structure, and includes a positive plate 9, a first diaphragm 6, a negative plate 7 and a second diaphragm 8, which are stacked;

as shown in fig. 3 and 4, the surface of the positive plate 9 is divided into a positive coating area 1, a positive tab area 3 and a smooth foil area 2, the smooth foil area 2 is arranged on one side of the width of the positive coating area 1, the positive tab area 3 is arranged on one side of the length of the positive coating area, and the positive tab area 3 and the smooth foil area 2 are distributed in an L shape; the surface of the negative plate 7 is divided into a negative coating area 4 and a negative lug area 5, and one side of the length of the negative coating area 4 is the negative lug area 5;

the positive coating area 1, the first diaphragm 6, the negative coating area 4 and the second diaphragm 8 are overlapped; the whole electric core periphery of 2 cladding in the smooth foil district of positive plate 9 forms electric core outer lane, and positive pole ear district 3 forms anodal ear, and negative pole ear district 5 forms the negative pole ear, and anodal ear and negative pole ear are located the both ends of electric core respectively.

The utility model provides an anodal ear and negative pole ear are the full utmost point ear structure of different sides, and anodal ear and negative pole ear are located the both ends symmetry setting of coiling electric core, directly with just, the inner and outer lane of negative pole piece switches on and links to each other, after the battery is pierced by the acupuncture, can conduct electric core current everywhere and heat fast, avoid local overflowing the heat production and lead to electric core thermal runaway's problem to the acupuncture security performance of coiling electric core has been promoted.

The utility model discloses an outer lane is the smooth paper tinsel district 2 of not coating positive pole thick liquids, has avoided by the extension just, the processing procedure yield problem of the vest structural design of negative current collector, moreover, compares the conventional outer lane and ends with the diaphragm of extension, also has better electric current and heat conduction effect, more is favorable to improving the acupuncture security performance of coiling electric core.

The distance between the edge of the positive electrode tab and the near edge of the first diaphragm 6 is 13-17 mm, the distance between the edge of the negative electrode tab and the near edge of the first diaphragm 6 is 13-17 mm, the length of the first diaphragm 6 is greater than the length of the negative coating area 4 by 5-10 mm, the width of the first diaphragm 6 is greater than the width of the negative coating area 4 by 1-2 mm, the length of the negative coating area 4 is greater than the length of the positive coating area 1 by 5-10 mm, the width of the negative coating area 4 is greater than the width of the positive coating area 1 by 1-2 mm, the plane contour sizes of the first diaphragm 6 and the second diaphragm 8 are equal, and the thickness of the positive plate 9 where the optical foil area 2 is located is 12-16 mu m.

The first diaphragm 6 includes a base material, and both the upper surface and the lower surface of the base material are provided with a composite layer, and the structure of the first diaphragm 6 is the same as that of the second diaphragm 8.

The utility model discloses a PP, PE and PP three-layer complex film that stacks gradually compares individual layer polyolefin membrane, and it is good not only to have a thermal stability, and mechanical strength is also high, effectively avoids the diaphragm to be heated and warp.

The composite layer comprises a boehmite layer and a conductive polymer layer arranged on the surface of the boehmite layer and in pores, and the conductive polymer layer is made of polyquinoline, poly-p-phenylene or poly-p-phenylene sulfide.

In another embodiment, the present invention provides a needle-prick prevention soft package battery, which comprises the winding electric core according to the first aspect.

coating positive electrode slurry on an aluminum foil to form a positive electrode coating area 1 of a positive electrode plate 9, wherein uncoated areas are a positive electrode lug area 3 and a smooth foil area 2 respectively, and preparing to obtain the positive electrode plate 9; coating the copper foil with negative electrode slurry to form a negative electrode coating area 4 of a negative electrode sheet 7, wherein the uncoated area is a negative electrode ear area 5, and preparing the negative electrode sheet 7;

(II) coating boehmite layers on the upper surface and the lower surface of the diaphragm base material, and coating a conductive polymer on the boehmite layers in a spraying mode to prepare a first diaphragm 6 and a second diaphragm 8;

(III) range upon range of first diaphragm 6, negative pole piece 7, second diaphragm 8 and positive plate 9 that sets up, wherein, first diaphragm 6, anodal coating district 1, second diaphragm 8 and the coincidence of negative pole coating district, negative pole ear district 5 and anodal ear district 3 are located different sides, the preparation obtains after the coiling shaping coiling electric core, wherein, the whole electric core periphery of 2 cladding in the smooth foil district of positive plate 9 forms electric core outer lane, anodal ear district 3 forms anodal ear, and negative pole ear district 5 forms the negative pole ear, and anodal ear and negative pole ear are located the both ends of electric core respectively.

Example 1

The embodiment provides a winding battery cell, based on a specific embodiment, wherein a distance between an edge of a positive tab and a near edge of a first diaphragm 6 is 13mm, a distance between an edge of a negative tab and a near edge of the first diaphragm 6 is 17mm, a length of the first diaphragm 6 is greater than a length of a negative coating region 4 by 5mm, a width of the first diaphragm 6 is greater than a width of the negative coating region 4 by 2mm, a length of the negative coating region 4 is greater than a length of a positive coating region 1 by 7.5mm, a width of the negative coating region 4 is greater than a width of the positive coating region 1 by 1.5mm, a thickness of a positive plate 9 where a smooth foil region 2 is located is 14 μm, and a conductive polymer layer is made of polyquinoline.

Example 2

The embodiment provides a winding battery cell, based on a specific embodiment, wherein a distance between an edge of a positive electrode tab and a close edge of a first diaphragm 6 is 15mm, a distance between an edge of a negative electrode tab and a close edge of the first diaphragm 6 is 15mm, a length of the first diaphragm 6 is greater than a length of a negative electrode coating area 4 by 10mm, a width of the first diaphragm 6 is greater than a width of the negative electrode coating area 4 by 1.5mm, a length of the negative electrode coating area 4 is greater than a length of the positive electrode coating area 1 by 5mm, a width of the negative electrode coating area 4 is greater than a width of the positive electrode coating area 1 by 1mm, a thickness of a positive electrode sheet 9 where a smooth foil area 2 is located is 12 μm, and a conductive polymer layer is made of poly-p-phenylene sulfide.

Example 3

The embodiment provides a winding battery cell, based on a specific embodiment, wherein a distance between an edge of a positive tab and a near edge of a first diaphragm 6 is 17mm, a distance between an edge of a negative tab and a near edge of the first diaphragm 6 is 13mm, a length of the first diaphragm 6 is greater than a length of a negative coating area 4 by 7.5mm, a width of the first diaphragm 6 is greater than a width of the negative coating area 4 by 1mm, a length of the negative coating area 4 is greater than a length of a positive coating area 1 by 10mm, a width of the negative coating area 4 is greater than a width of the positive coating area 1 by 2mm, a thickness of a positive plate 9 where a smooth foil area 2 is located is 16 μm, and a conductive polymer layer is made of poly-p-phenylene.

The winding battery cell prepared in the embodiment 1-3 has a full tab structure with different sides of the positive tab and the negative tab, and the inner and outer rings of the positive and negative electrode sheets are directly connected through conduction. After the battery is pierced by the needle, can conduct electric current and heat everywhere with electric core more fast, avoid local overflowing the heat production and lead to electric core thermal runaway to the security performance has been promoted. In addition, the whole electric core periphery of smooth foil district 2 cladding through positive plate 9 forms electric core outer lane, avoids vest structural design's processing procedure yield problem, compares conventional outer lane and ends with the diaphragm of extension, has better electric current and heat conduction effect, further improves the acupuncture security performance of lithium cell.

The applicant states that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto, and those skilled in the art should understand that any changes or substitutions easily conceivable by those skilled in the art within the technical scope of the present invention are within the protection scope and the disclosure scope of the present invention.

Claims

1. A winding battery cell comprises a positive plate, a first diaphragm, a negative plate and a second diaphragm which are arranged in a stacked mode, and the winding battery cell is of a winding body structure after winding; the surface of the negative plate is divided into a negative coating area and a negative lug area, and one side of the length of the negative coating area is the negative lug area;

2. The wound cell of claim 1, wherein the length of the first separator is 5-10 mm greater than the length of the negative coating region;

the width of the first diaphragm is 1-2 mm larger than that of the negative coating area;

the length of the negative electrode coating area is 5-10 mm greater than that of the positive electrode coating area;

the width of the negative electrode coating area is 1-2 mm larger than that of the positive electrode coating area;

the first and second diaphragms have equal planar profile dimensions.

3. The winding cell of claim 1, wherein the distance between the edge of the positive tab and the edge close to the first separator is 13-17 mm;

the distance between the edge of the negative electrode tab and the edge close to the first diaphragm is 13-17 mm.

4. The winding battery cell of claim 1, wherein the positive electrode sheet with the optical foil region is 12-16 μm thick.

5. The wound cell of claim 1, wherein the first separator comprises a substrate, and a composite layer is disposed on both the upper surface and the lower surface of the substrate;

the first diaphragm has the same structure as the second diaphragm.

6. The wound cell of claim 5, wherein the substrate comprises a PP layer, a PE layer, and a PP layer in a stacked arrangement.

7. The wound cell of claim 5, wherein the composite layer comprises a boehmite layer and a conductive polymer layer disposed on a surface of the boehmite layer.

8. The winding cell of claim 7, wherein the boehmite layer is provided with a conductive polymer within the pores.

9. The winding core according to claim 7, wherein the conductive polymer layer is made of any one of polyquinoline, poly-p-phenylene or poly-p-phenylene sulfide.

10. An anti-needle-punching soft package battery, which is characterized by comprising the winding battery core of any one of claims 1 to 9.