Safe high-capacity lithium electrode plate
By using self-adhesive tape on the positive electrode of the lithium battery, the surface unevenness and safety hazards caused by thickness transition are solved, capacity improvement and safety improvement are achieved, and costs are reduced.
Patent Information
- Application Number
- CN202323495512.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-21
- Publication Date
- 2024-12-24
- Estimated Expiration
- 2033-12-21
AI Technical Summary
The surface of the lithium battery positive electrode sheet structure is uneven due to the thickness transition, which poses safety hazards. The existing protection plan will cause some capacity loss when covered with PET-based tape.
The aluminum foil substrate is pasted with a self-adhesive tape body, including a polypropylene substrate and an adhesive layer, and bonded to the aluminum foil substrate through the adhesive layer to improve the size and safety of the positive electrode sheet.
The capacity and safety of the positive electrode of the lithium battery are improved, capacity loss is avoided, manufacturing costs are reduced and material utilization is improved.
Smart Images
Figure CN222233671U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of battery pole pieces, in particular to a safe high-capacity lithium electrode piece. Background Art
[0002] Lithium batteries are a type of battery that uses lithium metal or lithium alloy as positive / negative electrode materials and non-aqueous electrolyte solutions. In 1912, lithium metal batteries were first proposed and studied by Gilbert N. Lewis. In the 1970s, MS Whittingham proposed and began to study lithium-ion batteries. Due to the very active chemical properties of lithium metal, the processing, storage, and use of lithium metal have very high environmental requirements.
[0003] The existing positive electrode sheet structure in the lithium battery industry is a slurry coated on an aluminum foil. At the beginning and the end, there is an obvious cross-section due to the transition of thickness, resulting in an uneven surface of the electrode sheet, which subsequently leads to safety problems. The existing protection solution is to use PET-based tape to cover the electrode sheet covering area and the empty foil to prevent the sharp slope between the material area and the empty foil from piercing the isolation membrane and causing a safety accident. Since part of the material area is covered by the tape, the battery will lose part of its capacity. For the principle of safety first, the problem of capacity loss can only be compromised. Therefore, the present application proposes a safe high-capacity lithium electrode sheet. Utility Model Content
[0004] The utility model aims to provide a safe high-capacity lithium electrode sheet, which is applied to an aluminum foil substrate by a self-adhesive tape body, thereby increasing the size of the positive electrode of the lithium battery, increasing the capacity of the positive electrode of the lithium battery and its safety, so as to solve the problem that the existing positive electrode sheet structure in the lithium battery industry proposed in the above-mentioned background technology is that the slurry is coated on the aluminum foil, and at the beginning and the tail, there is an obvious cross-section at this place due to the transition of thickness, resulting in an uneven surface of the electrode sheet, which subsequently leads to safety problems. The existing protection scheme is to use PET-based tape to cover the electrode sheet covering area and the empty foil to avoid the sharp slope between the material area and the empty foil piercing the isolation membrane and causing a safety accident. Since part of the material area is covered by the tape, the battery will lose part of its capacity. Out of the principle of safety first, the problem of capacity loss can only be compromised at present.
[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a safe high-capacity lithium electrode sheet, comprising an aluminum foil substrate, a self-adhesive tape body is arranged on the top of the aluminum foil substrate, the self-adhesive tape body comprises a polypropylene base layer, a plurality of uniform air holes are uniformly opened through the top of the polypropylene base layer, an adhesive layer is coated on one end of the polypropylene base layer close to the aluminum foil substrate, and the self-adhesive tape body is bonded to the top of the aluminum foil substrate through the adhesive layer.
[0006] Compared with the prior art, the beneficial effects of the utility model are as follows: in the utility model, the aluminum foil substrate is attached by the self-adhesive tape body, thereby increasing the size of the positive electrode of the lithium battery, and increasing the capacity and safety of the positive electrode of the lithium battery. BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 This is a schematic diagram of the main structure of a safe high-capacity lithium electrode sheet of the utility model;
[0008] Figure 2 This is a schematic diagram of the exploded structure of the self-adhesive tape body in a safe high-capacity lithium electrode sheet of the utility model;
[0009] Figure 3 This utility model is a safe high-capacity lithium electrode sheet Figure 3 A schematic diagram of the structure enlargement at the center A;
[0010] Figure 4 Schematic diagram of excessive coating thickness for lithium battery positive electrode;
[0011] Figure 5 Schematic diagram of coating the positive electrode of a lithium battery with a PET-based tape.
[0012] In the figure: 1, aluminum foil substrate; 2, self-adhesive tape body; 21, polypropylene base layer; 22, uniform air permeability holes; 23, adhesive layer. DETAILED DESCRIPTION
[0013] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0014] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.
[0015] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0016] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "set" should be understood in a broad sense, for example, they can be fixedly connected or set, or detachably connected or set, or integrally connected or set. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0017] See also Figures 1 to 3 In an embodiment of the utility model, a safe high-capacity lithium electrode sheet includes an aluminum foil substrate 1, a self-adhesive tape body 2 is arranged on the top of the aluminum foil substrate 1, the self-adhesive tape body 2 includes a polypropylene base layer 21, a plurality of uniform air holes 22 are uniformly opened on the top of the polypropylene base layer 21, an end of the polypropylene base layer 21 close to the aluminum foil substrate 1 is coated with an adhesive layer 23, and the self-adhesive tape body 2 is bonded to the top of the aluminum foil substrate 1 through the adhesive layer 23.
[0018] like Figure 4-Figure 5 As shown in the figure, the existing positive electrode structure in the lithium battery industry is that the slurry is coated on the aluminum foil. At the beginning and the end, due to the thickness transition ( Figure 1 ), resulting in an obvious cross section here, resulting in an uneven surface of the electrode, which subsequently leads to safety problems. The existing protection solution is to use PET-based tape to cover the area between the electrode covering material and the empty foil ( Figure 2 ) to prevent the sharp slope between the material area and the empty foil from piercing the isolation membrane and causing a safety accident. Since part of the material area is covered by the tape, the battery will lose some capacity.
[0019] In this embodiment, the substrate is a PP (polypropylene) material with a porous structure, and a single-sided adhesive tape (acrylic or acrylic acid or a mixture of the two). The structure of the tape is as follows: Figure 2 After using this tape, the size of the cover material can be increased from 1-2mm to 3-4mm, avoiding insulation failure caused by the sawtooth of the coating tail not being insulated or machine errors. It improves safety without affecting capacity. Taking a pole piece with a length of about 500mm as an example, the capacity of the manufactured pole piece is increased by about 1-2% compared with the pole piece with PET tape, which improves the utilization rate of materials, reduces costs and increases the battery energy density.
[0020] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.
[0021] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.
Claims
1. A safe high-capacity lithium electrode sheet, comprising an aluminum foil substrate (1), characterized in that: A self-adhesive tape body (2) is arranged on the top of the aluminum foil substrate (1), and the self-adhesive tape body (2) includes a polypropylene base layer (21), and a plurality of uniform air holes (22) are uniformly opened through the top of the polypropylene base layer (21), and an adhesive layer (23) is coated on one end of the polypropylene base layer (21) close to the aluminum foil substrate (1), and the self-adhesive tape body (2) is bonded to the top of the aluminum foil substrate (1) through the adhesive layer (23).