End rubberizing structure of battery roll core and secondary battery

Abstract

The utility model discloses an ending rubberizing structure of a battery roll core and a secondary battery, the structure comprises the battery roll core, the battery roll core is formed by sequentially laminating and winding a first diaphragm, a first pole piece, a second diaphragm and a second pole piece, the number of the battery roll core is n, and n meets the relational expression that n is greater than or equal to 2; the double-sided protective glue comprises a first glue body and a second glue body, the first glue body comprises a surface A and a surface B which is oppositely arranged, and the second glue body comprises a surface C and a surface D which is oppositely arranged; the A surface is connected with the tail end of the second pole piece, the B surface is connected with the tail end of the second diaphragm, the C surface is connected with the tail end of the first diaphragm, and the D surface is connected with (n-1) circles of second pole pieces. Compared with the prior art, the double-sided protective glue is arranged at the ending part of the battery roll core, so that the four layers of materials at the ending part can be prevented from being integrally separated from the roll core, the integrity of the roll core is ensured, the material cost is reduced, the thickness of the roll core is reduced, and the volume energy density of the battery can be improved.

Description

Technical Field

[0001] The utility model belongs to the field of battery production, and in particular relates to a battery coil core tail glue-taping structure and a secondary battery. Background Art

[0002] Secondary batteries generally include battery cells, electrolytes and battery cases. Among them, battery cells can be divided into laminated battery cells and roll cores. In the field of power lithium batteries, roll cores have certain advantages. During the production process of the roll core, the winding end needs to be tailored and fixed. The end of the existing roll core structure contains a long section of empty aluminum foil, two layers of protective glue, two layers of diaphragms and a small section of empty copper foil. The empty aluminum foil goes around the corner of the roll core and extends to the other side of the roll core before being glued. However, the end of the roll core is redundant, consumes more raw materials, and to a certain extent increases the thickness of the roll core, reducing the energy density of the battery cell. For this reason, it is urgent to propose a new technical solution to solve the above problems. Utility Model Content

[0003] The purpose of the utility model is to address the deficiencies of the existing technology and provide a battery core end glue structure. By setting double-sided protective tape to fix the end of the core, the core material at the end is prevented from separating from the core, the integrity of the core after the end is ensured, the material cost is reduced, the thickness of the core is reduced, and the volume energy density of the battery cell is improved.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] A battery core finishing and gluing structure, comprising: a battery core, wherein the battery core is formed by sequentially stacking and winding a first diaphragm, a first electrode sheet, a second diaphragm, and a second electrode sheet, wherein the battery core has n turns, and n satisfies the relationship: n≥2;

[0006] A double-sided protective adhesive includes a first colloid and a second colloid, wherein the first colloid and the second colloid are an integrally molded structure or a split structure, wherein the first colloid includes an A surface and an oppositely arranged B surface, and the second colloid includes a C surface and an oppositely arranged D surface; the A surface is connected to the end of the second electrode piece, the B surface is connected to the end of the second diaphragm, the C surface is connected to the end of the first diaphragm, and the D surface is connected to the (n-1)th circle of the second electrode piece.

[0007] Preferably, the double-sided protective tape is in a U-shape or a V-shape.

[0008] Preferably, the lengths of the first colloid and the second colloid are both 0-20 mm.

[0009] Preferably, the thickness of the double-sided protective adhesive is 5-50 μm.

[0010] Preferably, a portion of the second pole piece connected to the double-sided protective adhesive is pretreated by laser cleaning.

[0011] Preferably, the A surface, the B surface, the C surface and the D surface are all provided with an adhesive layer, and the adhesive layer comprises acrylate.

[0012] Preferably, the heat-resistant temperature range of the double-sided protective adhesive is ≥150°C.

[0013] Preferably, the double-sided protective adhesive further includes a connecting portion, the connecting portion connecting the first colloid and the second colloid, and the connecting portion is connected to the (n-1)th turn of the second pole piece.

[0014] Preferably, the length of the connecting portion is 0-5 mm.

[0015] The utility model also provides a secondary battery, comprising the battery roll core tail glue-taping structure mentioned above.

[0016] The beneficial effect of the present invention is that the tail glue structure of the battery roll core provided by the present invention includes: a battery roll core, wherein the battery roll core is formed by stacking and winding a first diaphragm, a first electrode, a second diaphragm and a second electrode in sequence, and the battery roll core has n turns, and n satisfies the relationship: n≥2; a double-sided protective glue, including a first colloid and a second colloid, wherein the first colloid includes an A surface and an oppositely arranged B surface, and the second colloid includes a C surface and an oppositely arranged D surface; the A surface is connected to the end of the second electrode piece, the B surface is connected to the end of the second diaphragm, the C surface is connected to the end of the first diaphragm, and the D surface is connected to the (n-1)th turn of the second electrode piece. Compared with the existing technology, the present application directly fixes the ends of the first diaphragm, the first electrode sheet, the second diaphragm and the second electrode sheet by setting double-sided protective glue at the end of the battery roll core. On the one hand, the double-sided protective glue is connected to the end of the first diaphragm and the end of the second diaphragm respectively, which can prevent the diaphragm from shrinking and causing contact and fire between the positive and negative electrodes during subsequent battery cell operation; on the other hand, it can prevent the four layers of material at the end from detaching from the roll core as a whole, ensure the integrity of the roll core, reduce material costs, reduce the thickness of the roll core, and improve the volume energy density of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The features, advantages and technical effects of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings.

[0018] Figure 1 This is a structural schematic diagram of the end-taping glue structure of the battery roll core in the present invention.

[0019] Figure 2 It is an enlarged view of point A in the present utility model.

[0020] The description of the accompanying drawings is as follows:

[0021] 1. Double-sided protective tape; 11. First colloid; 12. Second colloid; 13. Connecting part; 2. Battery roll core; 21. First diaphragm; 22. First pole piece; 23. Second diaphragm; 24. Second pole piece. DETAILED DESCRIPTION

[0022] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0023] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application 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 drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0024] Reference to an "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment 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.

[0025] In the description of this application, it should be noted that, unless otherwise specified or limited, the term "connection" should be understood in a broad sense. For example, it can mean a fixed connection, a detachable connection, or an integral connection; it can mean a direct connection, an indirect connection through an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0026] The following is combined with Figures 1 and 2 The present invention is further described in detail with reference to the following specific embodiments, but is not intended to limit the present invention.

[0027] like Figures 1 and 2As shown, a battery core finishing and gluing structure is provided, including: a battery core, wherein the battery core 2 is formed by sequentially stacking and winding a first diaphragm 21, a first electrode 22, a second diaphragm 23, and a second electrode 24, and the battery core has n turns, and n satisfies the relationship: n≥2; when the first electrode 22 is a positive electrode, the second electrode 24 is a negative electrode; when the first electrode 22 is a negative electrode, the second electrode 24 is a positive electrode;

[0028] The double-sided protective adhesive 1 comprises a first adhesive 11 and a second adhesive 12. The first and second adhesives 11, 12 are either integrally formed or separated. The first adhesive 11 comprises a side A and an opposing side B, while the second adhesive 12 comprises a side C and an opposing side D. Side A connects to the end of the second electrode sheet 24, side B connects to the end of the second separator 23, side C connects to the end of the first separator 21, and side D connects to the (n-1)th winding of the second electrode sheet 24. The double-sided protective adhesive 1 is integrally connected to the battery core and also to the first separator 21, second separator 23, and second electrode sheet 24, securing the ends of the battery core to the core. This ensures the integrity of the finished battery core, reduces material costs, reduces the thickness of the battery core, and improves the volumetric energy density of the battery cell. The double-sided protective adhesive 1 is connected to the ends of both the first separator 21 and second separator 23. This prevents separator shrinkage during subsequent battery cell operation, which could lead to contact between the positive and negative electrode sheets and fire.

[0029] In one embodiment of the present application, the double-sided protective tape 1 is U-shaped or V-shaped. Due to the different connection methods and shapes, the double-sided protective tape 1 presents a U-shaped or V-shaped shape. Other similar shapes are also possible. Compared to the traditional battery winding core structure that extends the separator and hollow foil to cover the protective tape, the U-shaped or V-shaped double-sided protective tape 1 end structure of this solution has the advantages of saving materials, reducing the thickness of the battery winding core, and improving the energy density of the battery.

[0030] In one embodiment of the present application, the lengths of the first colloid 11 and the second colloid 12 are both 0-20 mm, for example, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm, 10.5 mm, 11 mm, 11.5 mm, 12 mm, 12.5 mm, 13 mm, 13.5 mm, 14 mm, 14.5 mm, 15 mm, 15.5 mm, 16 mm, 16.5 mm, 17 mm, 17.5 mm, 18 mm, 18.5 mm, 19 mm, 19.5 mm, and 20 mm.

[0031] In one embodiment of the present application, the thickness of the double-sided protective tape 1 is 5-50 μm, for example, 5 μm, 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm, 8 μm, 8.5 μm, 9 μm, 9.5 μm, 10 μm, 10.5 μm, 11 μm, 11.5 μm, 12 μm, 12.5 μm, 13 μm, 13.5 μm, 14 μm, 14.5 μm, 15 μm, 15.5 μm, 16 μm, 16.5 μm, 17 μm, 17.5 μm, 18μm, 18.5μm, 19μm, 19.5μm, 20μm, 21μm, 22μm, 23μm, 24μm, 25μm, 26μm, 27μm, 28μm, 29μm, 30μm, 31μm, 32μm, 33μm, 34μm, 35μm, 36μm, 37μm, 38μm, 39μm, 40μm, 41μm, 42μm, 43μm, 44μm, 45μm, 46μm, 47μm, 48μm, 49μm, 50μm. Before applying the double-sided protective tape 1, this application will pre-treat the electrode of the adhesive part to ensure that the thickness of the battery core 2 is not increased and the energy density of the battery is not affected.

[0032] In one embodiment of the present application, the portion of the second electrode sheet 24 that connects to the double-sided protective tape 1 undergoes a pretreatment process using laser cleaning. Laser cleaning can be used to remove 65% to 75% of the thickness of the double-sided protective tape 1 and the second electrode sheet, ensuring that the thickness of the battery core 2 is not increased and the battery's energy density is not affected.

[0033] In one embodiment of the present application, the A surface, the B surface, the C surface, and the D surface are all provided with an adhesive layer, and the adhesive layer includes acrylate.

[0034] In one embodiment of the present application, the heat-resistant temperature range of the double-sided protective adhesive 1 is ≥150° C. The double-sided protective adhesive 1 used in the present application has good heat resistance.

[0035] In one embodiment of the present application, the double-sided protective adhesive 1 further includes a connecting portion 13 , which connects the first colloid 11 and the second colloid 12 , and is connected to the (n−1)th circle of the second electrode 24 .

[0036] In one embodiment of the present application, the length of the connecting portion 13 is 0-5 mm, for example, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, or 5 mm.

[0037] The utility model also provides a secondary battery, comprising the battery roll core tail glue-taping structure mentioned above.

[0038] The present invention also provides an electrical device, including the aforementioned secondary battery. The electrical device may be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, or an electric tool. A vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle. A new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle. Spacecraft include airplanes, rockets, space shuttles, and spacecraft. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers.

[0039] 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 battery core end glue structure, characterized in that: include: A battery core, wherein the battery core is formed by sequentially stacking and winding a first separator, a first electrode sheet, a second separator, and a second electrode sheet, wherein the battery core has n turns, and n satisfies the relationship: n ≥ 2; A double-sided protective adhesive comprises a first colloid and a second colloid, wherein the first colloid and the second colloid are an integrally molded structure or a split structure, wherein the first colloid comprises an A surface and an oppositely arranged B surface, and the second colloid comprises a C surface and an oppositely arranged D surface; the A surface is connected to the end of the second electrode piece, the B surface is connected to the end of the second diaphragm, the C surface is connected to the end of the first diaphragm, and the D surface is connected to the second electrode piece of n-1 turns.

2. The battery roll core tail glue structure according to claim 1, characterized in that: The double-sided protective adhesive is in a U-shaped or V-shaped shape.

3. The battery roll core tail glue structure according to claim 1, characterized in that: The lengths of the first colloid and the second colloid are both 0-20 mm.

4. The battery roll core tail glue structure according to claim 1, characterized in that: The thickness of the double-sided protective adhesive is 5-50 μm.

5. The battery roll core tail glue structure according to claim 1, characterized in that: The portion of the second pole piece connected to the double-sided protective adhesive is pretreated by laser cleaning.

6. The battery roll core tail glue structure according to claim 1, characterized in that: The A surface, the B surface, the C surface, and the D surface are all provided with an adhesive layer, and the adhesive layer includes acrylate.

7. The battery roll core tail glue structure according to claim 1, characterized in that: The heat-resistant temperature range of the double-sided protective adhesive is ≥150°C.

8. The battery roll core tail glue structure according to claim 1, characterized in that: The double-sided protective adhesive further includes a connecting portion, the connecting portion connecting the first colloid and the second colloid, and the connecting portion is connected to the second pole piece of the n-1 circle.

9. The battery coil core tail glue-taping structure according to claim 8, characterized in that: The length of the connecting portion is 0-5 mm.

10. A secondary battery, characterized in that: It includes the battery roll core tail glue structure as described in any one of claims 1 to 9.

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