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CN-121528914-B - Battery monomer, preparation method thereof, battery device, power utilization device and energy storage device

CN121528914BCN 121528914 BCN121528914 BCN 121528914BCN-121528914-B

Abstract

The application relates to the field of batteries, and provides a battery monomer, a preparation method thereof, a battery device, an electric device and an energy storage device, wherein the preparation method of the battery monomer comprises the steps of providing a battery core assembly, wherein the battery core assembly is formed by laminating or winding a positive plate, a diaphragm and a negative plate; the method comprises the steps of providing a shell, placing the battery cell assembly in the shell, providing electrolyte, injecting the electrolyte into the shell, and performing a formation step, wherein the negative plate comprises a current collector, a negative active material, a conductive agent and a binder, the binder comprises a functional polymer, and the functional polymer is formed into a molecular network structure through chemical bond connection by a first reaction unit, a second reaction unit and a third reaction unit. The application can realize the remarkable improvement of the cycle life of the negative electrode, remarkably improve the cycle stability and structural integrity of the silicon negative electrode, and provide effective technical support for the practicability of the high-capacity lithium ion battery.

Inventors

  • CHEN JING
  • YANG ZIXIANG
  • WU YUHAO
  • SHI HAOTIAN

Assignees

  • 浙江晶科储能有限公司

Dates

Publication Date
20260505
Application Date
20260114

Claims (16)

  1. 1. A method for preparing a battery cell, comprising: providing an electric core component, wherein the electric core component is formed by laminating or winding a positive plate, a diaphragm and a negative plate; providing a shell, and placing the battery cell assembly in the shell; providing an electrolyte and injecting the electrolyte into the shell; Carrying out a formation step; The negative electrode plate comprises a current collector, a negative electrode active material, a conductive agent and a binder, wherein the binder comprises a functional polymer, the functional polymer is formed by connecting a first reaction unit, a second reaction unit and a third reaction unit through chemical bonds to form a molecular network structure, the first reaction unit has a lithium ion coordination function, the second reaction unit has a mechanical response function, and the third reaction unit has an ion conduction function; The first reaction unit comprises a polymer containing an ether oxygen group, the second reaction unit comprises a spiropyran compound, and the third reaction unit comprises an ionic liquid.
  2. 2. The method of claim 1, wherein the structure of the functional polymer comprises a linear triblock structure, a star-shaped multi-arm structure, or a side chain graft structure.
  3. 3. The method for producing a battery cell according to claim 1, wherein the mass fraction of the first reaction unit in the binder is 30% -80%, the mole fraction of the second reaction unit in the binder is 0.5% -15%, and the mass fraction of the third reaction unit in the binder is 10% -60%.
  4. 4. The method for producing a battery cell according to claim 1 or 3, wherein the number average molecular weight of the first reaction unit is 1000g/mol to 100000g/mol.
  5. 5. The method for preparing a battery cell according to claim 1, wherein the binder is prepared by a stepwise synthesis method or a one-step copolymerization method.
  6. 6. The method of claim 5, wherein the step synthesis method comprises: Synthesizing a first reaction unit, a second reaction unit and a third reaction unit respectively; And synthesizing the first reaction unit, the second reaction unit and the third reaction unit into the adhesive by a controllable polymerization method, a gradual polymerization method, a click chemistry method or a post-functionalization method.
  7. 7. The method for preparing a battery cell according to claim 5, wherein the one-step copolymerization method comprises: mixing the first reaction unit, the second reaction unit and the third reaction unit with an initiator and a chain transfer agent in inert atmosphere, and carrying out one-step controllable free radical copolymerization reaction at 40-100 ℃, or And mixing the first reaction unit, the second reaction unit and the third reaction unit with an initiator and a catalyst in inert atmosphere, and carrying out one-step controllable free radical copolymerization at 40-100 ℃.
  8. 8. The method of claim 6, wherein the method of controlled polymerization comprises an atom transfer radical polymerization method or a reversible addition-fragmentation chain transfer polymerization method.
  9. 9. The method for producing a battery cell according to claim 8, wherein the atom transfer radical polymerization method comprises: The first reaction unit, the second reaction unit and the third reaction unit are dissolved in a solvent, an initiator and a catalyst are added, and the reaction is carried out in an inert atmosphere at 40-100 ℃.
  10. 10. The method of claim 1, wherein the binder further comprises an additive.
  11. 11. The method of manufacturing a battery cell according to claim 1, wherein the negative electrode active material comprises a silicon-based active material.
  12. 12. The method of claim 1, wherein the forming step comprises first charging and discharging at a rate of 0.05C to 0.2C.
  13. 13. A battery cell characterized by being obtained by the preparation method of any one of claims 1 to 12.
  14. 14. A battery device, comprising the battery cell of claim 13, wherein the battery device comprises one or more of a battery module, a battery pack, and an energy storage battery.
  15. 15. An electrical device, characterized in that it comprises a battery device according to claim 14, the battery device is used for providing electric energy.
  16. 16. An energy storage device comprising the battery device of claim 14 for storing electrical energy.

Description

Battery monomer, preparation method thereof, battery device, power utilization device and energy storage device Technical Field The application relates to the field of batteries, in particular to a battery monomer, a preparation method thereof, a battery device, an electricity utilization device and an energy storage device. Background Along with the continuous improvement of the energy density requirements of mobile electronic equipment and electric automobiles on batteries, the development of high-capacity anode materials has become a key direction of the technical development of lithium ion batteries. Silicon-based anode materials are considered as important candidate materials for the anode of the next generation lithium ion battery because of the advantages of the ultrahigh theoretical specific capacity (4200 mAh g -1, about 10 times of graphite) and the abundant earth reserves. Under this background, silicon-based negative electrode technology has become a strategic technical field that is being put into focus in the global battery industry. The silicon negative electrode material stores lithium ions through Li-Si alloying reaction, so that the weight energy density and the volume energy density of the battery can be greatly improved. The alloying reaction of silicon has a higher lithium storage capacity and faster reaction kinetics than the intercalation reaction of conventional graphite cathodes. This makes silicon-based negative electrodes suitable for not only high energy density applications, but also exhibit good prospects in high power applications such as fast charging. Disclosure of Invention The application provides a battery monomer, a preparation method thereof, a battery device, an electricity utilization device and an energy storage device, which are at least beneficial to realizing automatic equalization of electrode reaction. In one aspect, the present application provides a method for preparing a battery cell, comprising: providing an electric core component, wherein the electric core component is formed by laminating or winding a positive plate, a diaphragm and a negative plate; providing a shell, and placing the battery cell assembly in the shell; providing an electrolyte and injecting the electrolyte into the shell; Carrying out a formation step; The negative electrode plate comprises a current collector, a negative electrode active material, a conductive agent and a binder, wherein the binder comprises a functional polymer, the functional polymer is formed by connecting a first reaction unit, a second reaction unit and a third reaction unit through chemical bonds to form a molecular network structure, the first reaction unit has a lithium ion coordination function, the second reaction unit has a mechanical response function, and the third reaction unit has an ion conduction function. Optionally, the structure of the functional polymer comprises a linear triblock structure, a star-shaped multi-arm structure or a side chain grafting structure. Optionally, the mass fraction of the first reaction unit in the binder is 30% -80%, the mole fraction of the second reaction unit in the binder is 0.5% -15%, and the mass fraction of the third reaction unit in the binder is 10% -60%. Optionally, the number average molecular weight of the first reaction unit is 1000g/mol to 100000g/mol. Optionally, the preparation method of the adhesive comprises a step synthesis method or a one-step copolymerization method. Optionally, the step synthesis method comprises: Synthesizing a first reaction unit, a second reaction unit and a third reaction unit respectively; And synthesizing the first reaction unit, the second reaction unit and the third reaction unit into the adhesive by a controllable polymerization method, a gradual polymerization method, a click chemistry method or a post-functionalization method. Optionally, the one-step copolymerization method includes: mixing the first reaction unit, the second reaction unit and the third reaction unit with an initiator and a chain transfer agent in inert atmosphere, and carrying out one-step controllable free radical copolymerization reaction at 40-100 ℃, or And mixing the first reaction unit, the second reaction unit and the third reaction unit with an initiator and a catalyst in inert atmosphere, and carrying out one-step controllable free radical copolymerization at 40-100 ℃. Optionally, the first reaction unit comprises a polymer comprising ether oxygen groups. Optionally, the polymer containing ether oxygen group includes at least one of polyether polymer, polycarbonate polymer, and copolymer, wherein the copolymer is obtained by reacting the polyether polymer and the polycarbonate polymer. Optionally, the second reaction unit comprises a spiropyran compound. Optionally, the spiropyran compound comprises at least one of 6-nitrospiro [ benzopyran-2, 2 '-indole ], 1, 3-trimethylspiro [ indole-2, 3' -naphtho [2,1-b ] [1,4] thiazine ], spiro [ benzopyran-2,