CN217691223U - Pole piece structure and battery - Google Patents

Abstract

The utility model provides a pole piece structure and battery. The pole piece structure comprises a current collector, a first coating and a second coating, wherein the first coating and the second coating are respectively coated on two side surfaces of the current collector; the first coating is provided with a first groove for mounting a tab; and a second groove is formed in the position, corresponding to the first groove, of the second coating, and an insulating layer is filled in the second groove. Can improve the pole piece through this pole piece structure because of the problem of the pole piece unevenness that installation utmost point ear leads to, fully solve utmost point ear built-in structure promptly and lead to the pole piece unevenness to appear, finally lead to electric core to become the in-process because of the pressure inequality that the pole piece that electric core self roughness problem leads to bore, finally lead to shipment electricity core uneven surface to appear, sunken and wave deformation scheduling problem, fully solve the battery can lead to electric core stress inhomogeneous in circulation expansion process because of electric core roughness difference in long circulation process, finally lead to electric core expansion deformation, cause the capacity decay, the inflation inefficacy problem.

Description

Pole piece structure and battery

Technical Field

The utility model relates to a battery technology field, in particular to pole piece structure to and a battery that is provided with this pole piece structure.

Background

With the advent of the 5G era and the rapid development of lithium ion battery technology, people have made higher requirements on energy density, endurance and rapid charging capability of lithium ion batteries.

At present, in order to solve the problems of high energy density and long endurance of lithium ion batteries, the capacity of the batteries is generally required to be made as large as possible, and the pole pieces are made as thick as possible, so that the problems can be solved. Meanwhile, in order to improve the quick charging capacity of the lithium ion battery, developers start to move the lug to the positions of 3/4, 1/3, 1/2 and the like of the positive pole piece and the negative pole piece, so that the internal resistance of the battery cell is reduced, the polarization is reduced, the distribution of current density on the pole pieces in the charging and discharging process is optimized, and the quick charging capacity of the battery is improved.

In order to weld the tab in the middle of the pole piece, i.e. in the middle of the tab, the paste applied at the corresponding position on the pole piece must be cleaned, so that a depressed area is formed on the pole piece, and the position of the pole piece for mounting the tab is not smooth enough. Meanwhile, in order to meet the requirement of long endurance capacity of the lithium ion battery, the thickness of the pole piece is increased, and the problem of unevenness of a paste coating and cleaning area is further aggravated. In the process of electrical core formation, uneven pressure borne by the pole pieces can be caused due to the uneven problem of the pole pieces, and finally the problems of uneven surface, sinking, wave deformation and the like of the shipment electrical core are caused. Moreover, the battery with the problem can cause uneven stress on the battery cell in the cyclic expansion process due to the flatness problem of the battery cell in the long-cycle process, and finally causes the battery cell to expand and deform, thereby causing capacity attenuation and expansion failure.

Therefore, how to improve the flatness of the tab mounting position of the pole piece is a technical problem to be solved urgently by those skilled in the art.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model aims at providing a pole piece structure to and a battery that is provided with this pole piece structure can improve the roughness in the position of pole piece installation utmost point ear.

In order to achieve the above purpose, the utility model provides a following technical scheme:

a pole piece structure comprises a current collector, a first coating and a second coating, wherein the first coating and the second coating are respectively coated on two side faces of the current collector;

the first coating is provided with a first groove, and a tab is positioned in the first groove and connected with the current collector;

and a second groove is formed in the position, corresponding to the first groove, of the second coating, and an insulating layer is filled in the second groove.

In one possible implementation, the thickness g of the insulating layer satisfies the formula g = a + b-f ± x,

wherein:

a is the thickness of the first coating layer,

b is the thickness of the second coating layer,

f is the thickness of the tab,

x is a constant and has a value range of 3-5 μm.

In a possible implementation manner, the insulating layer includes an adhesive layer and a substrate layer, and the substrate layer is attached in the second groove through the adhesive layer;

the thickness of the insulating layer is equal to the sum of the thickness of the base material layer and the thickness of the bonding layer.

In one possible implementation, the thickness g of the insulating layer satisfies the condition g <10 μm, and the thickness of the adhesive layer is 2 ± 0.5 μm;

or the thickness g of the insulating layer meets the condition that 10 mu m is less than g and less than 30 mu m, and the ratio range of the thickness of the bonding layer to the thickness of the base material layer is 2:1 to 1:2;

or the thickness g of the insulating layer meets the condition that 30 μm < g <60 μm, and the ratio of the thickness of the bonding layer to the thickness of the base material layer is in the range of 1:1 to 1:2;

or the thickness g of the insulating layer meets the condition that g is larger than 60 mu m, the thickness of the bonding layer is 30 +/-5 mu m, and the thickness of the base material layer is larger than 30 mu m.

In one possible implementation, the substrate layer is a PET material layer.

In one possible implementation, the adhesive layer is a glue layer.

In a possible implementation manner, the pole piece structure further includes:

the first protective gummed paper covers the first groove;

and/or the second protective gummed paper covers the outside of the second groove.

In one possible implementation manner, the first protective gummed paper includes a first straight section and a first bent section, wherein: the first straight section covers the first groove, and the first bending section is attached to the single-side bending area of the pole piece;

the second protection adhesive tape includes second straight section, second bending segment, wherein: the second straight section covers the outside of the second groove, and the second bending section is attached to the single-side bending area of the pole piece.

In a possible implementation manner, the first protective gummed paper further includes a first extension section, and the first extension section and the first straight section are respectively connected to two ends of the first bending section;

the second protective gummed paper also comprises a second extension section, and the second extension section and the second straight section are respectively connected to two ends of the second bending section;

wherein:

the length of the first extension section in the length direction of the pole piece is 2mm to 5mm; the length of the second extension section in the length direction of the pole piece is 2mm to 5mm;

and/or the projection of the first extension section and the second extension section in the thickness direction of the pole piece is not overlapped with the projection of the first groove and the second groove in the thickness direction of the pole piece.

In one possible implementation manner, the first protective gummed paper is located on the winding inner side of the pole piece structure, and the second protective gummed paper is located on the winding outer side of the pole piece structure, wherein: in the length direction of the pole piece, the length of the first protective adhesive paper is greater than that of the second protective adhesive paper; and/or the thickness of the first protective gummed paper is larger than that of the second protective gummed paper; and/or the first protective gummed paper and the second protective gummed paper both comprise a second bonding layer and a second base material layer, and the thickness ratio range of the second base material layer of the first protective gummed paper and the second base material layer of the second protective gummed paper is 1-2.

In one possible implementation manner, the second protective gummed paper is located on the winding inner side of the pole piece structure, and the first protective gummed paper is located on the winding outer side of the pole piece structure, wherein: in the length direction of the pole piece, the length of the second protective gummed paper is greater than that of the first protective gummed paper; and/or the thickness of the second protective gummed paper is larger than that of the first protective gummed paper; and/or the second protective gummed paper and the first protective gummed paper both comprise a second bonding layer and a second base material layer, and the thickness ratio range of the second base material layer of the second protective gummed paper and the second base material layer of the first protective gummed paper is (1-2).

In a possible realization, the distance between the tab and the side edge of the winding core is 3mm to 12mm.

In a possible implementation manner, the tab and the current collector are fixedly connected through welding.

In one possible implementation, the pole piece structure is a positive pole piece or a negative pole piece.

A battery comprises the pole piece structure.

The utility model provides an among the pole piece structure, owing to be provided with the insulating layer in the second recess (being located the back of the first recess at utmost point ear place) to can balance the thickness difference of pole piece in this groove. Consequently, this pole piece structure can improve the pole piece because of the problem of the pole piece unevenness that installation utmost point ear leads to, fully solve utmost point ear built-in structure promptly and lead to the pole piece unevenness to appear, finally lead to electric core to become the in-process because of the uneven pressure that the pole piece that electric core self roughness problem leads to bore, finally lead to shipment electricity core uneven surface to appear, sunken and wave deformation scheduling problem, fully solve the battery can lead to electric core stress inhomogeneous in circulation expansion process because of electric core roughness difference in long circulation process, finally lead to electric core expansion deformation, cause the capacity decay, the inflation inefficacy problem.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic view of a production process of a pole piece structure in a comparative example provided by the present invention;

fig. 2 is a schematic view of a production flow of a pole piece structure in an exemplary embodiment provided by the present invention;

fig. 3 is a schematic structural diagram of an insulating layer in a pole piece structure in an exemplary embodiment provided by the present invention;

fig. 4 is a schematic diagram of a side structure of a winding core in an exemplary embodiment of the present invention;

fig. 5 is a schematic side view of a first protective gummed paper in an exemplary embodiment provided by the present invention;

fig. 6 is a schematic side structure diagram of a second protective adhesive paper in an exemplary embodiment provided by the present invention.

Wherein:

1-pole piece, 2-groove,

21-a first groove, 22-a second groove,

3-a tab, 4-first protective gummed paper, 5-second protective gummed paper,

6-first coating, 7-second coating, 8-current collector, 9-insulating layer,

91-a first adhesive layer, 92-a second substrate layer,

41-a first straight section, 42-a first bending section, 43-a first extension section,

51-a second straight section, 52-a second bent section, 53-a second elongated section.

Detailed Description

The specification describes example embodiments with reference to cross-sectional and/or plan views as idealized example figures. In the drawings, the thickness of layers and regions are exaggerated for clarity. Variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Therefore, the exemplary embodiments should not be construed as being limited to the shapes of the regions illustrated in the present specification but include deviations in shapes that result, for example, from manufacturing. The regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the actual shape of a region of a device and are not intended to limit the scope of the exemplary embodiments.

Unless otherwise defined, technical or scientific terms used in the embodiments of the present specification should have the ordinary meaning as understood by those having ordinary skill in the art to which the present invention belongs. The terms "first," "second," and the like as used in the embodiments of the present specification do not denote any order, quantity, or importance, but rather are provided to avoid mixing of constituent elements.

Unless the context requires otherwise, throughout the description, the term "comprising" is to be interpreted in an open, inclusive sense, i.e., as "including, but not limited to". In the description herein, the terms "one embodiment," "some embodiments," "example," "particular example" or "some examples" or the like are intended to indicate that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the disclosure. The schematic representations of the terms used above are not necessarily referring to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be included in any suitable manner in any one or more embodiments or examples. In describing some embodiments, expressions of "coupled" and "connected," along with their derivatives, may be used. For example, the term "connected" may be used in describing some embodiments to indicate that two or more elements are in direct physical or electrical contact with each other. As another example, some embodiments may be described using the term "coupled" to indicate that two or more elements are in direct physical or electrical contact. The embodiments disclosed herein are not necessarily limited to the description herein.

Comparative examples

In order to embody the utility model discloses an innovation technique and beneficial effect through the mode of contrast, the utility model provides a contrast embodiment specifically is a pole piece structure before improving, puts in its utmost point ear, and the production process please refer to fig. 1:

firstly, cleaning the pasting paste at the position for installing the tab 3 on the pole piece 1 to obtain a groove 2, at the moment, cleaning a part of the first coating 6 at one side of the pole piece 1 to expose the current collector 8 to obtain a first groove 21 for installing the tab 3, and at the moment, as shown in fig. 1, the tab 3 is positioned in the first groove 21 and connected with the current collector 8; correspondingly, the second coating 7 on the other side of the pole piece 1 is also partially cleaned, creating a second groove 22;

then, fixedly connecting the tab 3 in the first groove 21, generally by welding;

finally, the first protective gummed paper 4 and the second protective gummed paper 5 are respectively pasted outside the first groove 21 and the second groove 22 on the two sides of the pole piece 1.

In the pole piece structure obtained in this way, the pole piece thicknesses at the positions where the pole lugs 3 are installed on the pole piece 1 have the following relations:

h1＝a+b+c+d+e，

h2＝f+c+d+e，

h1＞h2，

wherein:

h1 is the thickness of the pole piece at the two sides of the groove 2,

h2 is the thickness of the pole piece in the pole lug welding area,

a is the thickness of the first coating layer 6,

b is the thickness of the second coating layer 7,

c is the thickness of the current collector 8 (e.g. foil),

d is the thickness of the first protective adhesive tape 4,

e is the thickness of the second protective adhesive paper 5,

f is the thickness of the tab 3.

Therefore, in the pole piece structure, the thickness h1 of the pole piece in the area where the pole lug is located is lower than the thickness h2 of the pole pieces on the two sides of the pole piece, so that the thickness of the pole piece at the position where the pole lug 3 is installed on the pole piece 1 is very uneven, and the flatness of the pole piece is low.

Exemplary embodiments

Put the structure in order to solve above-mentioned utmost point ear and lead to the pole piece unevenness, finally lead to electric core to appear sunken and wave deformation scheduling problem in utmost point ear welding area, the utility model provides a pole piece structure after improving, put in its utmost point ear, the production process please refer to fig. 2:

firstly, cleaning the paste on the position, used for mounting the tab 3, of the pole piece 1 to obtain a groove 2, cleaning a part of a first coating 6 on one side of the pole piece 1 to expose a current collector 8 to obtain a first groove 21 for mounting the tab 3, wherein at the moment, as shown in fig. 2, the connecting surface between the tab 3 and the current collector 8 is positioned in the first groove 21; correspondingly, the second coating 7 on the other side of the pole piece 1 is also partially cleaned, creating a second groove 22;

then, fixedly connecting the tab 3 in the first groove 21 (generally adopting a welding mode); an insulating layer 9 is arranged in the second groove 22;

and finally, respectively pasting the first protective gummed paper 4 and the second protective gummed paper 5 outside the first groove 21 and the second groove 22 on the two sides of the pole piece 1.

Wherein, insulating layer 9 can adopt different thickness according to actual need for compensate the problem of the pole piece thickness unevenness that leads to when needing to weld utmost point ear 3 washing scribble the cream, can improve the problem of battery roll core thickness unevenness.

In specific implementation, the thickness g of the insulating layer 9 satisfies the following relationship:

g＝a+b-f±x

wherein:

a is the thickness of the first coating 6,

b is the thickness of the second coating layer 7,

f is the thickness of the tab 3,

x is a constant and has a value range of 3-5 μm.

Furthermore, referring to fig. 3, the insulating layer 9 is a gummed paper, and includes a first adhesive layer 91 and a substrate layer 92, the first adhesive layer 91 is in contact with the current collector 8 (such as a foil) in the pole piece 1, and the substrate layer 92 is located outside the first adhesive layer 91, that is, the substrate layer 92 is attached in the second groove 22 through the adhesive layer 91. The thickness of the insulating layer 9 is equal to the sum of the thickness of the base material layer 92 and the thickness of the adhesive layer 91.

Preferably, the first adhesive layer 91 is a glue layer (i.e., a glue adhesive layer), and the substrate layer 92 is a PET material layer. The first adhesive layer 91 and the base material layer 92 satisfy the following requirements:

when the required thickness g of the insulating layer 9 meets the condition g <10 μm, the thickness of the first adhesive layer 91 can only be 2 +/-0.5 μm, and the PET layer can be selected optionally;

when the thickness g of the insulating layer 9 satisfies the condition 10 μm < g <30 μm, the ratio range of the thickness of the first adhesive layer 91 to the thickness of the base material layer 92 thereof needs to satisfy 2:1 to 1:2;

when the thickness g of the insulating layer 9 satisfies the condition 30 μm < g <60 μm, the ratio range of the thickness of the first adhesive layer 91 to the thickness of the base material layer 92 thereof needs to satisfy 1:1 to 1:2;

when the thickness g of the insulating layer 9 satisfies the condition g > 60 μm, the thickness of the first adhesive layer 91 can be only 30 ± 5 μm, and the thickness of the base material layer 92 can be any value larger than 30 μm.

In the pole piece structure, the insulating layer 9 is arranged in the second groove 22 (positioned on the back of the first groove 21 where the pole lug 2 is positioned), so that the thickness difference of the pole piece 1 in the groove can be balanced, and the flatness of the pole piece is ensured. Therefore, the pole piece structure can improve the problem that the pole piece is not flat due to the installation of the pole lug in the background technology and the comparative embodiment, namely, the problem that the pole piece is not flat due to the pole lug middle structure is fully solved, the problems of uneven surface, sinking, wave deformation and the like of a discharged battery cell are finally caused due to uneven pressure borne by the pole piece caused by the flatness problem of the battery cell in the formation process of the battery cell, and the problems of capacity attenuation, expansion failure and the like of the battery cell are finally caused due to uneven stress borne by the battery cell in the cyclic expansion process caused by poor flatness of the battery cell in the long cycle process.

During specific implementation, if the tab is close to the side edge of the battery, the edges of the first protective adhesive paper 4 and the second protective adhesive paper 5 may be attached to the arc of the side edge of the winding core, and the problem of turning over the adhesive paper or precipitating lithium from the edge of the adhesive paper easily occurs at the later stage of long circulation at the edge of the arc. Referring to fig. 4 to 6, the first protective adhesive tape 4 includes a first straight section 41 and a first bending section 42, the first straight section 41 covers the first groove 21, and the first bending section 42 is attached to the single-side bending area of the pole piece; the second protective gummed paper 5 comprises a second straight section 51 and a second bending section 52, the second straight section 51 covers the second groove 22, and the second bending section 52 is attached to the single-side bending area of the pole piece.

The problem that the edge of the arc is easy to generate the lithium on the edge of the gummed paper or the gummed paper in the later period of long circulation is solved. In a preferred embodiment:

referring to fig. 4 and 5, the first protective adhesive tape 4 further includes a first extension section 43, wherein the first bending section 42 is an arc structure adapted to the single-side bending area of the pole piece, the first extension section 43 and the first straight section 41 are respectively connected to two ends of the first bending section 42, and the length of the first extension section 43 in the length direction of the pole piece is 2mm to 5mm;

correspondingly, referring to fig. 4 and fig. 6, the second protective adhesive paper 5 further includes a second extending section 53, wherein the second bending section 52 is an arc structure adapted to the single-side bending area of the pole piece, the second extending section 53 and the second straight section 51 are respectively connected to two ends of the second bending section 52, and the length of the second extending section 53 in the length direction of the pole piece is 2mm to 5mm.

In practical implementation, the projection of the first extension 43 and/or the second extension 53 in the thickness direction of the pole piece does not overlap with the projection of the first groove 21 and/or the second groove 22 in the thickness direction of the pole piece. In other words, the projection of any one of the first extension 43 and the second extension 53 in the thickness direction of the pole piece does not overlap with the projection of any one of the first groove 21 and the second groove 22 in the thickness direction of the pole piece. Thereby being beneficial to ensuring the surface evenness of the battery.

In specific implementation, one of the first protective gummed paper 4 and the second protective gummed paper 5 is inner gummed paper positioned on the winding inner side of the pole piece, and the other is outer gummed paper positioned on the winding outer side of the pole piece.

Preferably, in the length direction of the pole piece, the length of the inner side gummed paper is greater than that of the outer side gummed paper, that is, the projection of the edge of the outer side gummed paper passing through the arc-shaped gummed paper at the side edge of the winding core is on the edge of the inner side gummed paper passing around the arc-shaped gummed paper at the side edge of the winding core. The method specifically comprises two conditions:

the first protective gummed paper 5 and the first protective gummed paper 4 are respectively positioned on the inner side and the outer side of the wound pole piece, and the length of the second extension section 53 is greater than that of the first extension section 43 in the length direction of the pole piece; (as shown in FIG. 4)

Second, the first protective gummed paper 4 and the second protective gummed paper 5 are respectively located on the inner side and the outer side of the winding of the pole piece, and the length of the first extension section 43 is greater than that of the second extension section 53 in the length direction of the pole piece.

In a preferred embodiment, the thickness of the inner adhesive tape is greater than the thickness of the outer adhesive tape.

Specifically, the inner and outer gummed papers each include a second adhesive layer and a second base material layer, and the thickness ratio range of the second base material layer of the inner gummed paper and the second base material layer of the outer gummed paper is preferably 1 to 2.

For example, the inner gummed paper and the outer gummed paper are both composed of a second bonding layer (such as a glue layer) and a second substrate layer, and the bonding layer thickness of the inner gummed paper and the bonding layer thickness of the outer gummed paper are the same and are both 2-4 μm; the difference lies in that the thickness of the base layer of the inner side gummed paper and the outer side gummed paper is different, which generally ensures that:

the second substrate layer of outside adhesive tape: the second base material layer =1 to 1 of the inner adhesive paper.

The second base material layer preferably includes at least one of polyethylene, polypropylene, polyester (PET), polyvinyl chloride, and polyimide, and more preferably a PET layer. The second adhesive layer includes: one of rubber pressure-sensitive adhesive, organic silicon pressure-sensitive adhesive, acrylic acid pressure-sensitive adhesive and polyurethane pressure-sensitive adhesive, and the rubber pressure-sensitive adhesive layer is preferred.

Through the above-mentioned optimal design to first protection adhesive tape 4 and second protection adhesive tape 5, can avoid rolling up the circular arc edge of core side effectively and appear turning over the problem that adhesive tape or adhesive tape edge lithium are analysed easily in long circulation later stage.

It should be noted that, when the distance between the tab 3 and the side edge of the winding core (i.e. S in fig. 4) is 3mm to 12mm, the lengths of the first protective adhesive paper 4 and the second protective adhesive paper 5 may be extended, so that the edges of the first protective adhesive paper 4 and the second protective adhesive paper 5 are attached to the circular arc of the side edge of the winding core. If S is larger than 12mm, the extension rubberizing structure is not recommended.

Furthermore, the embodiment of the utility model provides a battery, its positive plate is provided with above-mentioned pole piece structure, and/or, the negative pole piece is provided with above-mentioned pole piece structure. In particular implementations, the battery may be a lithium ion battery.

It should be noted that the insulating layer 9 has an effect of absorbing the electrolyte to cause swelling, and the thickness of the adhesive layer of the insulating layer 9 can be defined according to the swelling characteristic of the adhesive layer and the thickness characteristic of the pole piece, so as to better balance the thickness of the pole piece in the cycle process.

Further, the PET material referred to herein as Polyethylene terephthalate, commonly known as PET resin, is the most predominant type of thermoplastic polyester. However, in other embodiments, a person skilled in the art may select other suitable materials instead of the substrate layer according to actual needs, for example, BOPP (polypropylene), PVC (polyvinyl chloride), PU (polyurethane), or papers such as crepe paper and glassine paper, or one of metal materials such as copper foil and aluminum foil.

In addition, in the specific embodiment, a person skilled in the art may select a suitable material as the adhesive layer 91 according to actual needs, for example, one of acrylate, silicone, rubber, polyurethane, and the like. The present invention is not limited to this.

The basic principles of the present specification have been described above with reference to specific embodiments, but it should be noted that advantages, effects, and the like, mentioned in the specification are only examples and are not limiting, and the advantages, effects, and the like, should not be considered as necessarily possessed by various embodiments of the specification. Furthermore, the foregoing disclosure of specific details is for the purpose of illustration and description and is not intended to be limiting, since the description is not intended to be exhaustive or to be limited to the precise details set forth.

Claims (10)

1. The utility model provides a pole piece structure, includes the mass flow body (8), and coats respectively first coating (6) and second coating (7) of the both sides face of the mass flow body (8), its characterized in that:

the first coating (6) is provided with a first groove (21), and a tab (3) is positioned in the first groove (21) and connected with the current collector (8);

and a second groove (22) is formed in the position, corresponding to the first groove (21), of the second coating (7), and an insulating layer (9) is filled in the second groove (22).

2. The pole piece structure of claim 1, characterized in that the thickness g of the insulating layer (9) satisfies the formula g = a + b-f ± x,

wherein:

a is the thickness of the first coating (6),

b is the thickness of the second coating (7),

f is the thickness of the pole ear (3),

x is a constant and has a value range of 3-5 μm.

3. The pole piece structure of claim 1, wherein the insulating layer (9) comprises a first adhesive layer (91) and a first substrate layer (92), the first substrate layer (92) being affixed within the second groove (22) by the first adhesive layer (91);

the thickness of the insulating layer (9) is equal to the sum of the thickness of the first base material layer (92) and the thickness of the first bonding layer (91).

4. The pole piece structure of claim 3, characterized in that the thickness g of the insulating layer (9) satisfies the condition g <10 μm, the thickness of the first adhesive layer (91) being 2 ± 0.5 μm;

or the thickness g of the insulating layer (9) meets the condition that 10 [ mu ] m < g <30 [ mu ] m, and the ratio of the thickness of the first bonding layer (91) to the thickness of the first base material layer (92) is in the range of 2:1 to 1:2;

or the thickness g of the insulating layer (9) meets the condition that 30 [ mu ] m < g <60 [ mu ] m, and the ratio of the thickness of the first bonding layer (91) to the thickness of the first base material layer (92) is in the range of 1:1 to 1:2;

or the thickness g of the insulating layer (9) meets the condition that g is larger than 60 mu m, the thickness of the first bonding layer (91) is 30 +/-5 mu m, and the thickness of the first base material layer (92) is larger than 30 mu m.

5. The pole piece structure of claim 1, further comprising:

the first protective gummed paper (4) covers the first groove (21);

and/or a second protective gummed paper (5) covering the outside of the second groove (22).

6. The pole piece structure of claim 5, wherein the first protective gummed paper (4) comprises a first straight section (41), a first bent section (42), wherein: the first straight section (41) covers the first groove (21), and the first bending section (42) is attached to the single-side bending area of the pole piece;

the second protective gummed paper (5) comprises a second straight section (51) and a second bent section (52), wherein: the second straight section (51) covers the second groove (22), and the second bent section (52) is attached to the single-side bent area of the pole piece.

7. The pole piece structure of claim 6, wherein the first protective gummed paper (4) further comprises a first prolonged section (43), the first prolonged section (43) and the first flat section (41) are respectively connected to two ends of the first bending section (42);

the second protective gummed paper (5) further comprises a second extension section (53), and the second extension section (53) and the second straight section (51) are respectively connected to two ends of the second bending section (52);

wherein:

the length of the first extension section (43) in the length direction of the pole piece is 2mm to 5mm; the length of the second extension section (53) in the length direction of the pole piece is 2mm to 5mm;

and/or the projection of the first extension (43) and/or the second extension (53) in the thickness direction of the pole piece is not overlapped with the projection of the first groove (21) and/or the second groove (22) in the thickness direction of the pole piece.

8. The pole piece structure according to claim 7, wherein the first protective gummed paper (4) is located on the inside of the winding of the pole piece structure and the second protective gummed paper (5) is located on the outside of the winding of the pole piece structure, wherein: in the length direction of the pole piece, the length of the first protective adhesive paper (4) is greater than that of the second protective adhesive paper (5); and/or the thickness of the first protective gummed paper (4) is larger than that of the second protective gummed paper (5); and/or the first protective gummed paper (4) and the second protective gummed paper (5) both comprise a second bonding layer and a second base material layer, and the thickness ratio range of the second base material layer of the first protective gummed paper (4) and the second base material layer of the second protective gummed paper (5) is 1-2;

alternatively, the first and second electrodes may be,

the second protection adhesive tape (5) is located the coiling inboard of pole piece structure, first protection adhesive tape (4) is located the coiling outside of pole piece structure, wherein: in the length direction of the pole piece, the length of the second protective gummed paper (5) is greater than that of the first protective gummed paper (4); and/or the thickness of the second protective gummed paper (5) is larger than that of the first protective gummed paper (4); and/or the second protective gummed paper (5) and the first protective gummed paper (4) both comprise a second bonding layer and a second base material layer, and the thickness ratio range of the second base material layer of the second protective gummed paper (5) and the second base material layer of the first protective gummed paper (4) is 1-2.

9. A pole piece structure according to any one of claims 1 to 8, characterized in that the distance between the tab (3) and the side of the reeling core is 3 to 12mm.

10. A battery comprising a pole piece structure according to any one of claims 1 to 9.

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