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CN-122025839-A - Self-repairing polymer solid electrolyte and preparation method and application thereof

CN122025839ACN 122025839 ACN122025839 ACN 122025839ACN-122025839-A

Abstract

The invention provides a self-repairing polymer solid electrolyte and a preparation method and application thereof, and belongs to the technical field of solid electrolytes. The invention improves the solid electrolyte by physical blending, wherein EVA forms a dynamic polymer network in the polymer solid electrolyte, feCoNiMnZn forms a high-entropy alloy multi-metal active center, and the prepared polymer solid electrolyte has a self-repairing function.

Inventors

  • GUO ZENGCAI
  • WANG SHENGSHENG
  • MU JINGBO
  • HAO XUEWEI
  • WANG YANMING

Assignees

  • 河北工程大学

Dates

Publication Date
20260512
Application Date
20260225

Claims (10)

  1. 1. A method for preparing a self-repairing polymer solid electrolyte, which is characterized by comprising the following steps: (1) Carrying out first heat treatment on a carbon source to obtain graphite carbon nitride, carrying out grinding mixing, second heat treatment and acid soaking on the graphite carbon nitride and cobalt powder to obtain a nitrogen-doped hollow porous carbon cage; (2) Mixing a metal compound and a nitrogen-doped hollow porous carbon cage in a solvent, and sequentially performing drying and heat treatment to obtain HEA@NC; (3) Mixing HEA@NC and succinic anhydride in a solvent for reflux reaction to obtain HEA@NC-COOH; (4) Mixing the polymer blend solution with HEA@NC-COOH, and then scraping a film to obtain a self-repairing polymer solid electrolyte; the polymer blend solution is mainly prepared from polyethylene oxide, lithium salt, ethylene-vinyl acetate copolymer and solvent.
  2. 2. The method for producing a self-healing polymer solid electrolyte according to claim 1, wherein in the step (1), the first heat treatment includes a first stage heat treatment and a second stage heat treatment; The temperature rising rate of the first-stage heat treatment is 4-6 ℃ per minute, the temperature is 500-600 ℃ and the time is 2-6 hours, and the first-stage heat treatment is cooled to room temperature; The temperature rising rate of the second stage heat treatment is 4-6 ℃ per minute, the temperature is 400-600 ℃ and the time is 1-3 hours.
  3. 3. The method for preparing the self-repairing polymer solid electrolyte according to claim 1 or 2, wherein in the step (1), the mass ratio of graphite carbon nitride to cobalt powder is 1:0.8-1.2, the heating rate of the second heat treatment is 1-3 ℃ per minute, the temperature is 700-900 ℃ and the time is 1-3 hours.
  4. 4. The method for preparing a self-repairing polymer solid electrolyte according to claim 3, wherein in the step (2), the metal compound is an acetylacetonate metal compound, the acetylacetonate metal compound comprises ferric acetylacetonate, cobalt acetylacetonate, nickel acetylacetonate, manganese acetylacetonate and zinc acetylacetonate, the heating rate is 3-8 ℃ per minute, the temperature is 550-650 ℃ and the time is 1-3 hours.
  5. 5. The method for preparing the self-repairing polymer solid electrolyte according to claim 1,2 or 4, wherein in the step (3), the molar ratio of HEA@NC to succinic anhydride is 1:18-22, the temperature of the reflux reaction is 50-70 ℃ and the time is 10-14 h.
  6. 6. The method of preparing a self-healing polymer solid electrolyte according to claim 5, wherein in the step (4), the polymer blend solution is prepared by: mixing polyethylene oxide and lithium salt in tetrahydrofuran to obtain solution A; The ethylene-vinyl acetate copolymer is dissolved in tetrahydrofuran to obtain solution B, and then the solution B is dripped into the solution A to obtain a polymer blend solution.
  7. 7. The method for preparing a self-repairing polymer solid electrolyte according to claim 1 or 6, wherein the molar ratio of EO in polyethylene oxide to lithium ions in lithium salt is 16-20:1, the concentration of polyethylene oxide in solution A is 8-12 wt%, the concentration of ethylene-vinyl acetate copolymer in solution B is 8-12 wt%, and the volume ratio of solution A to solution B is 4-6:1.
  8. 8. The self-repairing polymer solid electrolyte prepared by the preparation method of the self-repairing polymer solid electrolyte according to any one of claims 1 to 7, wherein the self-repairing polymer solid electrolyte can be self-repaired by baking.
  9. 9. The self-healing polymer solid electrolyte according to claim 8, wherein the baking temperature is 50 to 80 ℃ for 20 to 40 minutes.
  10. 10. Use of the self-healing polymer solid electrolyte according to claim 8 or 9 in a solid state battery.

Description

Self-repairing polymer solid electrolyte and preparation method and application thereof Technical Field The invention relates to the technical field of solid electrolytes, in particular to a self-repairing polymer solid electrolyte, a preparation method and application thereof. Background The patent CN 119029215B is a composite current collector, a preparation method thereof and a cathode-free lithium battery, and mainly introduces a design method of the composite current collector, a first artificial SEI layer is formed on a metal substrate, the first artificial SEI layer comprises a high-entropy alloy and an oxide solid electrolyte, the high-entropy alloy can provide sufficient lithium-philic sites, induce the in-growth of lithium metal surfaces, and is favorable for the compact deposition of lithium metal, and the oxide solid electrolyte has excellent ion conducting capacity and can promote the rapid transport of lithium ions at an interface. The patent couples the lithium-philicity of the high-entropy alloy with the ionic conductivity of the solid electrolyte, but the preparation process of the used high-entropy alloy filler is complex, the high-entropy alloy is formed by combining five or more main group elements according to atoms, highly controllable physical vapor deposition or laser pulse deposition is often required for preparing the uniformly distributed high-entropy alloy diaphragm, and compared with the traditional synthesis method, the process has high preparation cost and low production efficiency, and if only a lithium-philic layer is used, the high-entropy alloy diaphragm faces challenges in the whole development. Patent application CN119833889 a composite separator, its method of preparation and battery, the composite separator comprising a base film and a coating, wherein the coating is made of high entropy alloy aerogel and a solid electrolyte, wherein the solid electrolyte comprises at least one of a sulfide solid electrolyte, an oxide solid electrolyte, a halide solid electrolyte or a polymer solid electrolyte. The high-temperature sintering of the high-entropy alloy and the retention of the aerogel pore structure in the technology have fundamental contradiction, the true aerogel is difficult to obtain by normal-pressure drying, a more perfect using method of the high-entropy alloy diaphragm is not found, the electrolyte is adsorbed by the high-specific-surface-area aerogel, the consumption of lithium salt is increased, and the engineering application is insufficient in the actual development process. MOF-DERIVED HIGH-Entropy Oxide A "CATALYTIC ENGINE" ACS CATALYSIS 15.21.21 (2025): 18493-18510. The prepared electrolyte is not subjected to microscopic and macroscopic physical property test, the mechanical strength and coating suitability of the catalyst are not discussed, the multi-metal synergistic active sites are fuzzy in attribution, the synergistic effect is lack of quantitative analysis, and the laboratory performance is outstanding in practical application but the engineering transformation prospect is not clear. The patent application CN 120666400A discloses a method for preparing an inert anode material by compounding ALCRFENIV high-entropy alloy and ceramic, wherein V element is introduced into the high-entropy alloy, the problem of ICP analysis of the V element is absent, and the problem of dissolution of single element in salt is solved, the high-entropy alloy has reaction risks at the interface of spinel ceramic, the industrialization prospect is limited, and vanadium pollution and interface reaction runaway are two potential risks. Disclosure of Invention The invention aims to provide a self-repairing polymer solid electrolyte, and a preparation method and application thereof, so as to solve the problem that the solid electrolyte in the prior art cannot be repaired due to mechanical or electrochemical damage. In order to achieve the above object, the present invention provides the following technical solutions: The invention provides a preparation method of a self-repairing polymer solid electrolyte, which comprises the following steps: (1) Carrying out first heat treatment on a carbon source to obtain graphite carbon nitride, carrying out grinding mixing, second heat treatment and acid soaking on the graphite carbon nitride and cobalt powder to obtain a nitrogen-doped hollow porous carbon cage; (2) Mixing a metal compound and a nitrogen-doped hollow porous carbon cage in a solvent, and sequentially performing drying and heat treatment to obtain HEA@NC; (3) Mixing HEA@NC and succinic anhydride in a solvent for reflux reaction to obtain HEA@NC-COOH; (4) Mixing the polymer blend solution with HEA@NC-COOH, and then scraping a film to obtain a self-repairing polymer solid electrolyte; the polymer blend solution is made primarily of polyethylene oxide (PEO), lithium salt, ethylene-vinyl acetate copolymer (EVA) and solvent. Preferably, in step (1), the first heat treatment comp