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CN-122025808-A - Preparation method of electrolyte and solid-liquid mixed battery

CN122025808ACN 122025808 ACN122025808 ACN 122025808ACN-122025808-A

Abstract

The invention provides an electrolyte, a preparation method of a solid-liquid hybrid battery and the solid-liquid hybrid battery, wherein the electrolyte comprises a liquid electrolyte, a polymerization monomer and a second temperature-sensitive initiator, the mass ratio of the polymerization monomer to the liquid electrolyte is 3:97-5:95, and the activation temperature of the second temperature-sensitive initiator is 55-65 ℃. In the preparation process stage of the battery, the second temperature-sensitive initiator is activated through a heating process to form solid electrolyte, so that the mechanical strength of the battery can be effectively improved, the fluidity of the electrolyte is inhibited, and the structural stability and safety of the battery at normal temperature and normal working temperature are enhanced.

Inventors

  • SU YANHONG
  • NIE BINBIN
  • JIANG SHAOQI
  • XIONG DANXIA
  • CHEN WENHAO
  • CAI QUAN
  • ZHA FANGZHENG

Assignees

  • 广东华电储能有限公司
  • 中国华电集团有限公司广东分公司

Dates

Publication Date
20260512
Application Date
20260122

Claims (10)

  1. 1. An electrolyte is characterized by comprising a liquid electrolyte, a polymerized monomer and a second temperature-sensitive initiator, wherein the mass ratio of the polymerized monomer to the liquid electrolyte is 3:97-5:95, and the activation temperature of the second temperature-sensitive initiator is 55-75 ℃.
  2. 2. The electrolyte of claim 1 wherein the polymeric monomer is selected from the group consisting of trimethylolpropane triacrylate or polyethylene glycol diacrylate.
  3. 3. The electrolyte of claim 1 wherein the second temperature sensitive initiator is selected from the group consisting of azobisisoheptonitrile and dicumyl peroxide.
  4. 4. The electrolyte of claim 1, wherein the mass of the second temperature sensitive initiator is 0.5% to 1.5% of the mass of the polymerized monomer.
  5. 5. The preparation method of the solid-liquid hybrid battery is characterized by comprising the following steps of: providing a positive plate, a negative plate and a diaphragm; loading a first temperature sensitive initiator on a separator, and the activation temperature of the first temperature sensitive initiator is 40 ℃ to 50 ℃; Preparing the electrolyte of any one of claims 1-4; Placing the diaphragm between the positive plate and the negative plate, and assembling an electric core; Injecting the electrolyte into the battery cell; Heating at 40-55deg.C for 0.5-2 hr, and heating at 55-65deg.C for 0.5-2 hr.
  6. 6. The method of claim 5, wherein the first temperature sensitive initiator is selected from the group consisting of azobisisobutyronitrile and lauroyl peroxide.
  7. 7. The method of claim 5, wherein the first temperature sensitive initiator is applied to the separator by solvent impregnation.
  8. 8. The method of claim 5, wherein the mass of the first temperature sensitive initiator is 0.5% to 1.5% of the mass of the polymerized monomer.
  9. 9. A solid-liquid hybrid battery, characterized in that the solid-liquid hybrid battery is produced by the production method according to any one of claims 5 to 8.
  10. 10. Use of the solid-liquid hybrid battery according to claim 9 in energy storage devices, electric vehicles, aircraft.

Description

Preparation method of electrolyte and solid-liquid mixed battery Technical Field The application relates to the technical field of batteries, in particular to a preparation method of an electrolyte and solid-liquid mixed battery and the solid-liquid mixed battery. Background With the rapid development of high energy density applications such as energy storage devices, electric vehicles and aircrafts, the safety and rate performance of secondary batteries such as lithium ion batteries have become a research hotspot. The traditional liquid electrolyte system has high ionic conductivity, can meet the high-rate charge and discharge requirements, but has potential safety hazards under high temperature or extreme working conditions, such as thermal runaway, fire and other problems. Solid electrolyte systems are of interest for their excellent thermal stability and safety, but their relatively low ionic conductivity limits further improvement in rate performance. In view of the above problems, various improvements have been proposed in the prior art, including development of a novel solid electrolyte, optimization of a separator structure, introduction of a polymer matrix, etc., in order to improve safety while taking into consideration the rate capability of the battery. However, the problems of poor contact of the solid electrolyte with the electrode interface, volume changes during curing, and uneven electrolyte distribution still affect the overall performance and reliability of the battery. How to realize the space distribution control of the electrolyte in the battery has become an important direction for improving the comprehensive performance of the battery. Disclosure of Invention In order to solve the technical problems, the application provides an electrolyte, a preparation method of a solid-liquid mixed battery and the solid-liquid mixed battery. The first aspect of the application provides an electrolyte comprising a liquid electrolyte, a polymerized monomer and a second temperature-sensitive initiator, wherein the mass ratio of the polymerized monomer to the liquid electrolyte is 3:97 to 5:95, and the activation temperature of the second temperature-sensitive initiator is 55 ℃ to 75 ℃. In the preparation process stage of the battery, a second temperature-sensitive initiator is activated through a heating process to initiate polymerization of the polymerization monomer, so that the solid electrolyte is formed. The solid electrolyte structure can effectively improve the mechanical strength of the battery and inhibit the fluidity of electrolyte, and the structural stability and the safety of the battery at normal temperature and normal working temperature are enhanced. Further, the polymeric monomer is selected from trimethylolpropane triacrylate or polyethylene glycol diacrylate. The monomer has good polymerization performance and electrochemical stability, and can form a compact solid electrolyte layer under the action of a temperature-sensitive initiator, so that the interface stability and safety of the battery are improved. Specifically, the trimethylolpropane triacrylate can be commercially available TMPTA, and the polyethylene glycol diacrylate can be PEGDA. Further, the second temperature sensitive initiator is selected from azobisisoheptonitrile or dicumyl peroxide. The initiator can be activated sequentially at different temperatures, so that the space and time distribution of the curing reaction is controllable. Specifically, the activation temperature of azobisisoheptonitrile was 60 ℃, and the activation temperature of dicumyl peroxide was 55 ℃. Further, the mass of the second temperature-sensitive initiator accounts for 0.5 to 1.5 percent of the mass of the polymerized monomer. The electrolyte is favorable for optimizing the mechanical strength, the ionic conductivity and the flame retardant property of the electrolyte after solidification, and the balance between the safety and the electrical property is realized. The second aspect of the application provides a preparation method of a solid-liquid hybrid battery, comprising the following steps: providing a positive plate, a negative plate and a diaphragm; loading a first temperature sensitive initiator on a separator, and the activation temperature of the first temperature sensitive initiator is 40 ℃ to 50 ℃; Preparing the electrolyte; Placing the diaphragm between the positive plate and the negative plate, and assembling an electric core; Injecting the electrolyte into the battery cell; Heating at 40-55deg.C for 0.5-2 hr, and heating at 55-65deg.C for 0.5-2 hr. According to the method, the diaphragm and the adjacent area thereof are preferentially solidified to form the solid electrolyte layer through step-by-step heating, and the liquid electrolyte is reserved in the anode material, so that layered solidification of the internal space distribution of the battery is realized. The first temperature-sensitive initiator may be selected from