Pole piece structure, laminated battery cell and battery

Abstract

The utility model belongs to the technical field of batteries, and particularly relates to a pole piece structure, a laminated battery cell and a battery. The pole piece structure comprises a current collector, and a prime coat structure and an active material layer structure which are coated on at least one surface of the current collector, the prime coat structure and the active material layer structure are sequentially stacked on the current collector; an empty foil area is arranged between the side end of the prime coat structure and the surface of the current collector; the prime coat structure comprises a prime coat main body and prime coat bulges; the prime coat main body is connected to the current collector; the prime coat protrusions are arranged in a protruding mode in the direction from the prime coat body to the active material layer structure. According to the utility model, the thickness difference of the pole piece structure can be reduced, the flatness of the surface of a battery cell formed by the pole piece structure is improved, the lithium precipitation problem of the head of the battery cell is effectively improved, and the use safety and stability are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of batteries, and in particular relates to a pole piece structure, a laminated battery core and a battery. Background Art

[0002] While lithium-ion batteries are widely used, they are also subject to increasingly higher consumer demands, such as high energy density, fast charging speed, and long battery life. In particular, the market is increasingly demanding fast-charging technology, and stacked-cell and multi-tab technologies are considered to be extremely promising in the field of lithium-ion battery fast charging.

[0003] In the manufacturing process of lithium-ion battery stacks, zebra coating technology is often used for positive and negative electrodes. However, the current zebra coating process has the difficulty of achieving zero thinning at the edges. In addition, the edge waste is not cut during stripping, resulting in the thickness of the electrode edges being thinner than the center. Therefore, after the electrodes are wound or stacked to form a battery cell, the thinner edges of the positive and negative electrodes correspond to the cell head. Due to the accumulation of thickness differences at all the electrode edges, the thickness of the cell head is less than the main body thickness, resulting in an uneven surface of the battery cell, uneven hot pressing during the formation process, and severe lithium deposition at the head during cycling, which reduces the safety and stability of use. Utility Model Content

[0004] The purpose of the utility model is to provide a pole piece structure to solve the technical problem that the prior art is prone to serious lithium deposition and reduces the safety and stability of use.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A pole piece structure comprises a current collector and a primer structure and an active material layer structure coated on at least one surface of the current collector; the primer structure and the active material layer structure are stacked in sequence on the current collector; an empty foil area is provided between the side end of the primer structure and the surface of the current collector; and the primer structure comprises a primer body and a primer protrusion; the primer body is connected to the current collector; and the primer protrusion is provided to protrude from the primer body toward the active material layer structure.

[0007] Preferably, at least one thinning groove is provided on the surface of the active material layer structure; and the projection of the primer protrusion toward the thinning groove covers the thinning groove.

[0008] Preferably, the primer protrusion is extended along the width direction of the primer body; and the primer protrusion is arranged at an edge position of the surface of the primer body.

[0009] Preferably, the relationship between the thickness h3 of the primer protrusion, the overall thickness h5 of the area where the primer protrusion is located, and the thickness h4 of the primer body satisfies: h5>h4; and h5=h4+h3.

[0010] Preferably, the thickness h4 of the primer body satisfies: 1 μm≤h4≤5 μm.

[0011] Preferably, the thickness h3 of the protruding portion of the primer relative to the main body satisfies: 2 μm≤h3≤5 μm.

[0012] Preferably, the overall thickness h5 of the area where the primer protrusion is located satisfies: 5 μm≤h5≤15 μm.

[0013] Preferably, the relationship between the length D2 of the thinning groove and the length D1 of the primer protrusion satisfies: 0mm≤D1≤10mm, 0mm≤D2≤10mm,

[0014] And 0mm≤|D2-D1|≤0.01mm.

[0015] Preferably, the relationship among the thickness h1 of the active material layer structure at locations other than the skived grooves, the thickness h2 of the active material layer structure at the skived grooves, and the thickness h3 of the primer protrusions satisfies: 95% h1≤h2≤h1; and h1≥h2+h3.

[0016] The utility model also discloses a laminated battery core, comprising a first pole piece and a second pole piece with opposite polarities and a diaphragm arranged between the first pole piece and the second pole piece; and the first pole piece and / or the second pole piece is the pole piece structure described above.

[0017] Preferably: the sum of the number of the first pole pieces and the second pole pieces is n, the thickness of the thinned groove in each of the first pole pieces or each of the second pole pieces is h0, and the relationship between the thickness of the primer protrusion h3 satisfies: h3=h0; the overall thin thickness of the battery cell head = 2*n*h0, that is, the thickness of the primer protruding part of all pole pieces compared to the main body = 2*n*h3.

[0018] The utility model also discloses a battery, comprising the laminated battery core.

[0019] The beneficial effect of the present utility model lies in that the technical solution adopts the method of setting the primer protrusions in the primer structure toward the protrusions of the active material layer structure to achieve thickening of the corresponding position of the active material layer structure, thereby effectively compensating for the thickness difference defect caused by the coating of the active material layer structure, thereby reducing the thickness difference of the pole piece structure, improving the flatness of the surface of the battery cell formed by the pole piece structure, and effectively improving the lithium plating problem at the head of the battery cell, thereby improving the safety and stability of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The following will refer to the attached Figures 1 to 5 To describe the features, advantages and technical effects of exemplary embodiments of the present invention.

[0021] Figure 1 This is a front view of a pole piece structure according to an embodiment of the present invention;

[0022] Figure 2 A top view of a pole piece structure according to an embodiment of the present invention;

[0023] Figure 3 This is a schematic structural diagram of a pole piece structure according to an embodiment of the present invention;

[0024] Figure 4 This is a schematic structural diagram of a pole piece structure according to an embodiment of the present invention;

[0025] Figure 5 This is a schematic structural diagram of a laminated battery cell according to an embodiment of the present invention.

[0026] In the figure: 1-current collector; 11-empty foil area; 2-primer structure; 21-primer body; 22-primer protrusion; 3-active material layer structure; 31-thinned groove; 100-first pole piece; 200-diaphragm; 300-second pole piece. DETAILED DESCRIPTION

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0028] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0029] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0030] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or multiple situations exist. In addition, the character " / " in this document generally indicates that the related objects are in an "or" relationship.

[0031] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0032] The following is combined with Figures 1 to 5 The present invention is further described in detail, but is not intended to limit the present invention.

[0033] like Figure 1 As shown, in one embodiment of the present invention, the electrode structure includes a current collector 1, a primer structure 2 and an active material layer structure 3 coated on at least one surface of the current collector 1 and stacked in sequence. A hollow foil region 11 is provided between the side end of the primer structure 2 and the surface of the current collector 1. The primer structure 2 includes a primer body 21 and primer protrusions 22. The primer body 21 is connected to the current collector 1. The primer protrusions 22 are arranged to protrude from the primer body 21 toward the active material layer structure 3. The active material layer structure 3 is coated on the surface of the primer structure 2 by zebra coating.

[0034] The technical solution of the present invention is to arrange the primer protrusions in the primer structure toward the protrusions of the active material layer structure to achieve thickening of the corresponding positions of the active material layer structure, thereby effectively compensating for the thickness difference defects caused when the active material layer structure is coated, thereby reducing the thickness difference of the pole piece structure, improving the flatness of the surface of the battery cell formed by the pole piece structure, and effectively improving the lithium plating problem at the head of the battery cell, thereby improving the safety and stability of use.

[0035] In some embodiments, when the current collector 1 is aluminum foil, the primer structure 2 is ceramic, etc., and the active material layer structure 3 is primarily composed of one or more of lithium cobalt oxide, lithium manganese oxide, lithium nickel manganese oxide, nickel cobalt manganese ternary material, or lithium iron phosphate, or a composite material thereof. When the current collector 1 is copper foil, the active material layer structure 3 is primarily composed of one or more of graphite, graphite-silicon carbon material, or graphite-silicon oxide material, and the primer structure 2 is a conductive agent, a binder, etc.

[0036] Specifically, in some embodiments, Figure 1 As shown, the surface of the active material layer structure 3 is provided with at least one thinning groove 31; and the projection of the primer protrusion 22 toward the thinning groove 31 covers the thinning groove 31. In other words, the projection area of the primer protrusion 22 toward the thinning groove 31 is greater than or equal to the cross-sectional area of the thinning groove 31. In other words, since the thinning groove 31 appears when the active material layer structure 3 is subjected to the zebra coating process on the pole piece structure, the addition of the primer protrusion 22 directly below the thinning groove 31 can effectively compress the thinning groove 31, thereby reducing its depth, thereby facilitating improved surface flatness of the pole piece structure.

[0037] Specifically, in some embodiments, Figures 1 to 3 As shown, the primer protrusions 22 extend along the width direction of the primer body 21 and are arranged in a protruding manner; and the number of the primer protrusions 22 is at least two and they are symmetrically arranged at the edge of the surface of the primer body 21. Figure 3 As shown, the width direction is the Y-axis direction. Furthermore, the projection of the side line of the primer protrusion 22 toward the primer body 21 coincides with the edge line of the edge position of the surface of the primer body 21. That is to say, since the electrode structure undergoes the zebra coating process of the active material layer structure 3, two symmetrical thinning grooves 31 will appear on the edge parts on both sides of the surface; therefore, the thinning groove 31 at each position is compressed by multiple primer protrusions 22, thereby reducing the depth of the thinning groove 31, which is beneficial to improving the surface flatness of the electrode structure. Among them, the cross-sectional shape of the primer protrusion 22 is a shape with the same or similar functional role, such as an arc or a truncated cone; they are not limited one by one here.

[0038] Specifically, in some embodiments, Figure 2 and 3As shown, the relationship between the overall thickness h5 of the area where the primer protrusion is located and the thickness h4 of the primer body 21 satisfies: h5>h4; and the thickness h4 of the primer body 21 satisfies: 1μm≤h4≤5μm; the thickness h3 of the primer protrusion 22 satisfies: 2μm≤h3≤5μm; the overall thickness h5 of the area where the primer protrusion is located satisfies: 3μm≤h5≤10μm. Figure 2 and 3 As shown, the thickness direction is the vertical direction of the Z axis. That is, by having a relatively small and reasonable thickness of the primer body 21, the overall thickness of the coating can be controlled, and the assembly stability of the active material layer structure 3 can be ensured, as well as the rationality and stability of the arrangement of the primer protrusions 22.

[0039] Specifically, in some embodiments, Figure 1 、 2 As shown in Figure 4, the relationship between the length D2 of the thinning groove 31 and the length D1 of the primer protrusion 22 satisfies the following: D2 = D1. Furthermore, 0mm≤D2≤10mm; 0mm≤D1≤10mm, and further, 0mm≤|D2-D1|≤0.01mm. In order to prevent the primer protrusion 22 from squeezing the unthinned area of the active material layer structure 3, thinning grooves 31 and primer protrusions 22 of equal length are provided, so as to relatively perfectly compensate for the thickness difference defect caused by edge thinning during zebra coating, significantly reduce the thickness difference between the edge of the electrode and the main body, and improve the surface flatness of the battery cell. When the technology develops to the setting of the primer protrusion 22 to achieve the thin edge defect of the battery cell head caused by the zebra coating process, D2 = 0. Wherein, the length direction is the horizontal direction of the X-axis.

[0040] Specifically, in some embodiments, Figure 3 and 4 As shown, the relationship between the thickness h1 of the active material layer structure 3 outside the thinning groove 31, the thickness h2 of the active material layer structure 3 at the thinning groove 31, and the thickness h3 of the primer protrusion 22 satisfies the following: h1>h2; and 95% of the time, h1≤h2≤h1, and h1≥h2+h3. Preferably, h1>h2; and h1=h2+h3. Preferably, h1>h2; and h1=h2+h3. Due to the compressive effect of the primer protrusion 22, the thickness of the thinning groove 31 can be compressed to 0%-5% of the thickness of the active material layer structure 3. This helps to compensate for the thinning problem in the cell head caused by the thinning area. This results in a flatter cell structure, more uniform formation hot pressing stress, a denser and smoother SE I film, and significantly increased adhesion between the electrode and separator, effectively improving the lithium deposition problem in the cell head.

[0041] The present invention also proposes a laminated battery cell, such as Figure 5 As shown, the laminated battery cell includes at least one first pole piece 100 and at least one second pole piece 300 with opposite polarities and a diaphragm 200 arranged between adjacent first pole pieces 100 and second pole pieces 300; and the first pole piece 100 and / or the second pole piece 300 are pole piece structures; the specific structure of the pole piece structure refers to the above embodiment. Since the first pole piece 100 and / or the second pole piece 300 adopt all the technical solutions of all the above embodiments, they at least have all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here. Among them, the first pole piece 100 is a negative pole piece, and the second pole piece 300 is a positive pole piece; or, the first pole piece 100 is a positive pole piece, and the second pole piece 300 is a negative pole piece. Among them, as Figure 5 As shown, the relationship between the sum of the number of first pole pieces 100 and second pole pieces 300 (n), the thickness of the skived groove 31 in each first pole piece 100 or each second pole piece 300 (h0), and the thickness h3 of the primer protrusion 22 satisfies: h3 = h0. In other words, in a battery cell, the sum of the thickness h3 of all the primer protrusions 22 of the pole pieces relative to the main body is equal to the cumulative sum of the thickness differences of the skived areas at the edges of the zebra-coated pole pieces, i.e., the thickness of the top of the cell being thinner than the main body.

[0042] The diaphragm 200 includes but is not limited to one or more of polyethylene, polypropylene, polyvinylidene fluoride, and multilayer composite films thereof.

[0043] The present invention also proposes a battery, which includes a laminated battery cell. The specific structure of the laminated battery cell refers to the above-mentioned embodiment. Since this battery adopts all the technical solutions of all the above-mentioned embodiments, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0044] Example 1

[0045] Positive Electrode: A current collector 1 (aluminum foil) is designed based on the zebra coating dimensions. A ceramic primer structure 2 (slurry coating) is applied to the aluminum foil. The thickness and width of the thickened edge protrusions 22 of the primer structure 2 are controlled. The active material LiCoO2, conductive agent superconducting carbon, conductive carbon nanotubes, and binder polyvinylidene fluoride (PVDF) are then fully dispersed in an N-methylpyrrolidone solvent system at a weight ratio of 97.6:0.6:0.5:1.3 and evenly coated onto the primer-coated aluminum foil current collector 1 to form the active material layer structure 3 on the aluminum foil current collector 1. The product is then cold-pressed and slit to produce the positive electrode. The thickened area of the primer protrusion 22 on the aluminum foil current collector 1: thickness h3 = 3 μm, the coating width of the protrusion area D1 = 10 mm; the thinned area width D2 = 10 mm, the primer body thickness h4 = 1 μm, the overall thickness h5 = 4 μm of the area where the primer protrusion is located, the thickness h1 of the active material layer structure at the non-thinned groove and the thickness h2 of the active material layer structure at the thinned groove satisfy the relationship: h2 = 95% h1.

[0046] Negative electrode sheet: The negative electrode active material, conductive agent, and binder are mixed in a weight ratio of 97.6:1.1:1.3 to form the negative electrode active material layer structure 3. This is then coated onto the corresponding base-coated copper foil current collector 1. A thickened area with coating protrusions 22 is provided at the edge of the copper foil current collector 1, and the negative electrode sheet is cold pressed. The thickened area with coating protrusions 22 on the copper foil current collector 1 has a thickness h3 of 3 μm, a coating width D1 of 10 mm in the protruding area, a skived area width D2 of 10 mm, a base coating main body thickness h4 of 1 μm, and an overall thickness h5 of 4 μm in the area containing the base coating protrusions. The thickness h1 of the active material layer structure outside the skived grooves satisfies the thickness h2 of the active material layer structure within the skived grooves: h2 = 95% of h1.

[0047] Diaphragm 200: The PE surface is coated with a ceramic mixture to form the diaphragm 200.

[0048] Electrolyte: Ethylene carbonate (EC), propylene carbonate (PC), diethyl carbonate (DEC), and propyl propionate (PP) are mixed in a volume ratio of 1:1:4:4, and then fully dried lithium salt Li PF6 is dissolved in a mixed organic solvent at a ratio of 1 mol / L to prepare an electrolyte.

[0049] Preparation of a full battery: The above-mentioned positive electrode sheets, separators, and negative electrode sheets are used to make bare cells, which are then encapsulated and injected with electrolyte to make finished lithium-ion batteries. The bonding strength is estimated by using a tensile tester to test the tensile force between the electrode and the separator in the bare cell after hot pressing of the stacked sheets. The cycle retention rate is the percentage of the remaining capacity to the initial capacity after the cell is step-charged at 5.0C to 4.10V, at a rate of 4.0C to 4.20V, at a rate of 2.5C to 4.30V, and at a rate of 1.5C to 4.50V for 1000 cycles. The lithium plating interface is obtained by disassembling the cell after 1000 cycles.

[0050] Example 2

[0051] The difference between Example 2 and Example 1 is that the values of the thickened area of the coating protrusion 22 on the aluminum foil current collector 1 and the copper foil current collector 1 are: thickness h3 = 2 μm, the coating width of the protrusion area D1 = 10 mm; the thinning area width D2 = 10 mm, the primer body thickness h4 = 1 μm, the overall thickness of the area where the primer protrusion is located h5 = 4 μm, and the thickness h1 of the active material layer structure at the non-thinning groove and the thickness h2 of the active material layer structure at the thinning groove satisfy the relationship: h2 = 95% h1.

[0052] Example 3

[0053] The difference between Example 3 and Example 1 is that the values of the thickened area of the coating protrusion 22 on the aluminum foil current collector 1 and the copper foil current collector 1 are: thickness h3 = 5 μm, the coating width of the protrusion area D1 = 10 mm; the thinning area width D2 = 10 mm, the primer body thickness h4 = 1 μm, the overall thickness of the area where the primer protrusion is located h5 = 4 μm, the thickness h1 of the active material layer structure at the non-thinning groove and the thickness h2 of the active material layer structure at the thinning groove satisfy the relationship: h2 = 95% h1.

[0054] Example 4

[0055] The difference between Example 4 and Example 1 is that the values of the thickened area of the coating protrusion 22 on the aluminum foil current collector 1 and the copper foil current collector 1 are: thickness h3 = 3 μm, the coating width of the protrusion area D1 = 15 mm; the thinning area width D2 = 10 mm, the primer body thickness h4 = 1 μm, the overall thickness of the area where the primer protrusion is located h5 = 4 μm, and the thickness h1 of the active material layer structure at the non-thinning groove and the thickness h2 of the active material layer structure at the thinning groove satisfy the relationship: h2 = 95% h1.

[0056] Example 5

[0057] The difference between Example 5 and Example 1 is that the values of the thickened area of the coating protrusion 22 on the aluminum foil current collector 1 and the copper foil current collector 1 are: thickness h3 = 3 μm, the coating width of the protrusion area D1 = 5 mm; the thinning area width D2 = 10 mm, the primer body thickness h4 = 1 μm, the overall thickness of the area where the primer protrusion is located h5 = 4 μm, and the thickness h1 of the active material layer structure at the non-thinning groove and the thickness h2 of the active material layer structure at the thinning groove satisfy the relationship: h2 = 95% h1.

[0058] Comparative Example 1

[0059] The difference between Comparative Example 1 and Example 1 is that the values of the thickened area of the coating protrusion 22 on the aluminum foil current collector 1 and the copper foil current collector 1 are: thickness h3 = 3 μm, the coating width of the protrusion area D1 = 0 mm; the width of the thinned area D2 = 10 mm, the thickness of the primer body h4 = 1 μm, the overall thickness of the area where the primer protrusion is located h5 = 4 μm, and the thickness h1 of the active material layer structure at the non-thinned groove and the thickness h2 of the active material layer structure at the thinned groove satisfy the relationship: h2 = 95% h1.

[0060] Comparative Example 2

[0061] The differences between Comparative Example 2 and Example 1 are: thickness h3 = 6 μm, coating width D1 of the raised area = 10 mm; width D2 of the thinned area = 10 mm, thickness of the primer body h4 = 1 μm, overall thickness h5 = 4 μm of the primer protrusion area, thickness h1 of the active material layer structure at locations other than the thinned groove and thickness h2 of the active material layer structure at the thinned groove satisfy the relationship: h2 = 95% h1.

[0062] Table 1-Experimental data table

[0063] Experimental example Adhesion force N / m Capacity retention rate% Volume expansion rate% Lithium deposition interface Example 1 9.48 97.81％ 10.41％ No lithium precipitation Example 2 7.71 85.76％ 14.38％ Slight lithium deposition Example 3 5.39 82.35％ 17.87％ Moderate lithium precipitation Example 4 8.47 88.85％ 12.72％ Slight lithium deposition Example 5 7.18 84.63％ 16.43％ Slight lithium deposition Comparative Example 1 2.28 75.28％ 21.70％ Severe lithium deposition Comparative Example 2 2.90 78.63％ 22.53％ Severe lithium deposition

[0064] It can be seen from Table 1 that when the thickened area of the primer protrusion 22 is set at a specific position on the primer foil in this solution, the defect of thin edge of the battery head caused by the zebra coating process can be compensated. The prepared battery cell has greater adhesion between the electrode and the diaphragm after hot pressing. During the formation process of the lithium-ion battery, the entire surface is smoother and the force is more uniform. The formed SE I film is denser and smoother, which significantly improves the performance of the battery cell during the cycle process, has a lower cycle expansion rate, and the lithium plating situation at the head is significantly improved.

[0065] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0066] Based on the disclosure and teachings of the above description, those skilled in the art will be able to make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments described above. Any obvious improvements, substitutions, or modifications made by those skilled in the art based on the present invention fall within the scope of protection of the present invention. In addition, although certain specific terms are used in this description, these terms are for convenience only and do not constitute any limitation on the present invention.

Claims

1. A pole piece structure, characterized in that: It includes a current collector and a primer structure and an active material layer structure coated on at least one surface of the current collector; the primer structure and the active material layer structure are stacked in sequence on the current collector; an empty foil area is provided between the side end of the primer structure and the surface of the current collector; and the primer structure includes a primer body and a primer protrusion; the primer body is connected to the current collector; the primer protrusion is protruded from the primer body toward the active material layer structure.

2. The pole piece structure according to claim 1, characterized in that: The surface of the active material layer structure is provided with at least one thinning groove; and the projection of the primer protrusion toward the thinning groove covers the thinning groove.

3. The pole piece structure according to claim 1 or 2, characterized in that: The primer protrusions are extended along the width direction of the primer body; and the primer protrusions are arranged at edge positions of the surface of the primer body.

4. The pole piece structure according to claim 3, characterized in that: The relationship between the thickness h3 of the primer protrusion, the overall thickness h5 of the region where the primer protrusion is located, and the thickness h4 of the primer body satisfies: h5>h4; and h5=h4+h3.

5. The pole piece structure according to claim 4, characterized in that: The thickness h4 of the primer body satisfies: 1 μm≤h4≤5 μm.

6. The pole piece structure according to claim 4, characterized in that: The thickness h3 of the protruding portion of the primer relative to the main body satisfies: 2 μm≤h3≤5 μm.

7. The pole piece structure according to claim 4, characterized in that: The overall thickness h5 of the area where the primer protrusion is located satisfies the following: 5 μm≤h5≤15 μm.

8. The pole piece structure according to claim 2, characterized in that: The relationship between the length D2 of the thinning groove and the length D1 of the primer protrusion satisfies: 0mm≤D1≤10mm, 0mm≤D2≤10mm, And 0mm≤|D2-D1|≤0.01mm.

9. The pole piece structure according to claim 2 or 8, characterized in that: The relationship among the thickness h1 of the active material layer structure at locations other than the skived grooves, the thickness h2 of the active material layer structure at the skived grooves, and the thickness h3 of the primer protrusions satisfies: 95% h1≤h2≤h1; and h1≥h2+h3.

10. A laminated battery cell, characterized in that: It comprises a first pole piece and a second pole piece with opposite polarities and a diaphragm arranged between the first pole piece and the second pole piece; and the first pole piece and / or the second pole piece is the pole piece structure according to any one of claims 1 to 9 above.

11. The laminated battery cell according to claim 10, characterized in that: The relationship between the sum of the number of the first pole pieces and the second pole pieces is n, the thickness of the thinned groove in each of the first pole pieces or each of the second pole pieces is h0, and the thickness of the primer protrusion h3 satisfies: h3=h0; the overall thin thickness of the battery cell head = 2*n*h0, that is, the thickness of the primer protruding part of all pole pieces compared to the main body = 2*n*h3.

12. A battery, characterized in that: Including the laminated battery core according to claim 10 or 11.

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