CN-122025983-A - Bottom support sheet, preparation method and battery

CN122025983ACN 122025983 ACN122025983 ACN 122025983ACN-122025983-A

Abstract

The invention provides a bottom support sheet, a preparation method and a battery, which are applied to the technical field of batteries, wherein the bottom support sheet is arranged in the battery and comprises an insulating base material, at least one side surface of the insulating base material is provided with a composite coating of a lithium molecular sieve and an adhesive, the composite coating is provided with a three-dimensional porous structure, and the three-dimensional porous structure is of a microporous structure and is used for adsorbing water and hydrogen fluoride in the battery and storing and slowly releasing electrolyte. The bottom support sheet is used for arranging the composite coating on the insulating substrate serving as the bottom support sheet of the battery, and multiple effective adsorption of water and hydrogen fluoride in the battery can be realized without changing the structure and space of the conventional battery. Meanwhile, the three-dimensional porous structure of the composite coating has excellent electrolyte wettability and storage capacity, and can gradually release the stored electrolyte in the middle and later stages of circulation, so that the consumption of the electrolyte is effectively compensated.

Inventors

WEI CUI
ZHU FUQIN
LU WENWEN
GAO HAIYANG
ZHAO LISHUN
LI GONGQIANG

Assignees

山东圣阳电源股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260309

Claims (10)

1. The bottom support sheet is arranged in a battery and comprises an insulating base material, wherein a composite coating of a lithium molecular sieve and an adhesive is arranged on at least one side surface of the insulating base material, the composite coating has a three-dimensional porous structure, and the three-dimensional porous structure is of a microporous structure and is used for adsorbing water and hydrogen fluoride in the battery and storing and slowly releasing electrolyte.
2. The underwire sheet of claim 1, wherein the framework type of the composite coated lithium molecular sieve comprises a composite of the framework structure of any one of the following materials or the framework structure of any combination of materials: a type a molecular sieve or a type X molecular sieve.
3. The underwire sheet of claim 2, wherein the framework type of the lithium type molecular sieve of the composite coating is a composite structure of the framework structure of the a type molecular sieve and the framework structure of the X type molecular sieve.
4. The underwire sheet of claim 1, wherein the adhesive of the composite coating comprises any one of polyvinylidene fluoride, polyacrylate.
5. The underwire sheet of claim 1 wherein the same side surface of the insulating substrate has a first region and a second region, the first region being provided with the composite coating and the second region being provided with an insulating coating.
6. The underwire sheet of claim 5, wherein the first and second regions together comprise the same side surface of the insulating base material, the first region being located at a contiguous edge region of the same side surface, the second region being located at a central region of the same side surface.
7. A method of making a shoe insert according to any one of claims 1-6, comprising: preparing lithium molecular sieve powder; preparing slurry of a composite coating by using the lithium molecular sieve powder and the adhesive; coating the slurry of the composite coating on at least one side surface of the insulating substrate to prepare the composite coating; wherein the composite coating has a three-dimensional porous structure.
8. The method of preparing a shoe according to claim 7, wherein the preparing lithium molecular sieve powder comprises: Providing molecular sieve raw powder; the molecular sieve raw powder and the mixture containing Carrying out ion exchange reaction on the exchange liquid, filtering, washing and drying to obtain molecular sieve powder after lithium ion exchange; And carrying out degassing and activating treatment on the molecular sieve powder subjected to lithium ion exchange at 300-350 ℃ for 0.5-3 hours to obtain the lithium molecular sieve powder.
9. A battery, comprising a housing, a cell, an electrolyte, and a shoe according to any one of claims 1-6, wherein the cell and the shoe are disposed inside the housing, and the shoe is disposed at the bottom of the cell.
10. The battery of claim 9, wherein the composite coating of the shoe tab is in direct contact with the cell bottom.

Description

Bottom support sheet, preparation method and battery Technical Field The invention relates to the technical field of batteries, in particular to a bottom bracket sheet, a preparation method and a battery. Background Although the lithium ion battery is baked in the manufacturing process, trace water still cannot be avoided to remain in the lithium ion battery). During long-term circulation, the trace amount of water can undergo side reactions with lithium salts in the electrolyte to generate hydrogen fluoride, hydrofluoric acid with strong corrosiveness and the like. The generation of hydrofluoric acid can damage the structure of the electrolyte interface film, so that the electrode active material is dropped off, the current collector is corroded, and the performance of the battery is accelerated and attenuated. At present, a mode of placing a separate adsorption pack in a battery is often adopted to adsorb moisture and hydrogen fluoride. However, the independent adsorption pack occupies valuable internal space of the battery, and the adsorption effect is poor. In addition, the electrolyte is gradually lost during long-term circulation of the battery, so that the interfacial ion conductivity is reduced, and the conventional adsorption structure generally does not have the function of supplementing or maintaining the electrolyte. Therefore, it is necessary to provide a bottom support sheet, a preparation method and a battery, so as to solve the technical problems that the adsorption effect of the existing adsorption structure is poor and electrolyte cannot be supplemented or maintained on the premise of not changing the internal structure of the battery. Disclosure of Invention The invention aims to provide a bottom support sheet, a preparation method and a battery, which can solve the technical problems that the prior adsorption structure has poor adsorption effect and cannot supplement or maintain electrolyte under the premise of not changing the internal structure of the battery. In order to solve the technical problems, the invention provides a bottom support sheet which is arranged in a battery and comprises an insulating base material, wherein a composite coating of a lithium molecular sieve and an adhesive is arranged on at least one side surface of the insulating base material, the composite coating has a three-dimensional porous structure, and the three-dimensional porous structure is of a microporous structure and is used for adsorbing water and hydrogen fluoride in the battery and storing and slowly releasing electrolyte. Optionally, the framework type of the lithium molecular sieve of the composite coating comprises a framework structure of any one of the following materials or a composite structure of framework structures of any combination of materials: a type a molecular sieve or a type X molecular sieve. Optionally, the framework type of the lithium type molecular sieve of the composite coating is a composite structure of the framework structure of the A type molecular sieve and the framework structure of the X type molecular sieve. Optionally, the adhesive of the composite coating comprises any one of polyvinylidene fluoride and polyacrylate. Optionally, the same side surface of the insulating substrate has a first region and a second region, the first region is provided with the composite coating, and the second region is provided with the insulating coating. Optionally, the first region and the second region together form a same side surface of the insulating substrate, the first region is located in a connected edge region of the same side surface, and the second region is located in a central region of the same side surface. The invention also provides a preparation method of the shoe pad, which is used for preparing any one of the shoe pad, and comprises the following steps: preparing lithium molecular sieve powder; preparing slurry of a composite coating by using the lithium molecular sieve powder and the adhesive; coating the slurry of the composite coating on at least one side surface of the insulating substrate to prepare the composite coating; wherein the composite coating has a three-dimensional porous structure. Optionally, the preparing lithium molecular sieve powder includes: Providing molecular sieve raw powder; the molecular sieve raw powder and the mixture containing Carrying out ion exchange reaction on the exchange liquid, filtering, washing and drying to obtain molecular sieve powder after lithium ion exchange; And carrying out degassing and activating treatment on the molecular sieve powder subjected to lithium ion exchange at 300-350 ℃ for 0.5-3 hours to obtain the lithium molecular sieve powder. The invention also provides a battery, which comprises a shell, a battery core, electrolyte and any one of the bottom support sheets, wherein the battery core and the bottom support sheets are arranged in the shell, and the bottom support sheets are positioned at the bottom of