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CN-122000482-A - Battery cell, manufacturing method thereof, battery device, power utilization device and energy storage device

CN122000482ACN 122000482 ACN122000482 ACN 122000482ACN-122000482-A

Abstract

The application provides a battery monomer and a manufacturing method thereof, a battery device, an electric device and an energy storage device, wherein the manufacturing method of the battery monomer comprises the steps of providing a substrate, and depositing h-BN on the substrate; the preparation method comprises the steps of carrying out fluorination treatment on h-BN to enable B atoms in the h-BN and F atoms to form B-F covalent bonds, stripping the h-BN from a substrate to obtain fluorinated h-BN, preparing first electrolyte which comprises lithium salt, an additive, a diluent and a solvent, dispersing the fluorinated h-BN into the first electrolyte to obtain second electrolyte which comprises lithium nitrate, providing a positive plate, a negative plate and a diaphragm, sequentially laminating the positive plate, the diaphragm and the negative plate, carrying out winding treatment or lamination treatment, then placing the laminated positive plate, the laminated diaphragm and the negative plate into a shell, and injecting the second electrolyte into the shell to carry out a formation process to obtain the battery monomer. At least to the improvement of the performance of the battery cell.

Inventors

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

Assignees

  • 浙江晶科储能有限公司

Dates

Publication Date
20260508
Application Date
20260410

Claims (18)

  1. 1. A method for manufacturing a battery cell, comprising: providing a substrate, and depositing h-BN on the substrate; Carrying out fluorination treatment on the h-BN so as to enable B atoms in the h-BN and F atoms to form B-F covalent bonds; Stripping the h-BN from the substrate to obtain fluorinated h-BN; preparing a first electrolyte, wherein the first electrolyte comprises lithium salt, an additive, a diluent and a solvent; dispersing the fluorinated h-BN into the first electrolyte to obtain a second electrolyte, wherein the second electrolyte comprises lithium nitrate; Providing a positive plate, a negative plate and a diaphragm, sequentially laminating the positive plate, the diaphragm and the negative plate, and placing the positive plate, the diaphragm and the negative plate into a shell after winding or lamination treatment; and injecting the second electrolyte into the shell, and performing a formation process to obtain a battery monomer.
  2. 2. The method of producing a battery cell according to claim 1, wherein the atomic ratio of F atoms, B atoms and N atoms in the fluorinated h-BN is (0.2 to 0.8): 1:1.
  3. 3. The method of producing a battery cell according to claim 1, wherein prior to the fluorination treatment of the h-BN, the h-BN is subjected to a functional modification, the h-BN is first placed in a UV-O 3 cleaner to graft the h-BN to-OH and/or-COOH, and then the h-BN is added to an amino group-containing coupling agent to form Si-O bonds to-OH and/or-COOH.
  4. 4. The method according to claim 1, wherein the first electrolyte contains lithium nitrate, or wherein the step of dispersing the fluorinated h-BN into the first electrolyte comprises: Dispersing the fluorinated h-BN into a mixed solution of lithium nitrate and hexafluoroisopropanol; Displacing the fluorinated h-BN into an intermediate solvent with a boiling point lower than 100 ℃ by adopting a gradient dilution method; The intermediate solvent in which the fluorinated h-BN is dispersed is added dropwise to the first electrolyte.
  5. 5. The method for producing a battery cell according to claim 4, wherein after dropping the intermediate solvent in which the fluorinated h-BN is dispersed into the first electrolyte, a rotary evaporation treatment is performed to remove the intermediate solvent.
  6. 6. The method for producing a battery cell according to claim 4 or 5, wherein the intermediate solvent is one or more selected from the group consisting of dimethyl carbonate, acetonitrile and tetrahydrofuran.
  7. 7. The method for producing a battery cell according to claim 4 or 5, wherein the concentration of lithium nitrate in the mixed solution of lithium nitrate and hexafluoroisopropanol is 0.05mol/L to 0.3mol/L.
  8. 8. The method according to claim 1, wherein the additive comprises a film formation promoter selected from one or more of a borate compound, a boron-containing lithium salt compound, a fluorinated solvent, and a silicon boron hybrid compound, and an inducer selected from one or more of a boron halide complex, an aluminum-based Lewis acid, an organoboron Lewis acid, and a boron-containing lithium salt.
  9. 9. The method of manufacturing a battery cell according to claim 1, wherein the step of injecting the second electrolyte into the case and performing the formation process includes: dividing the second electrolyte into a third electrolyte and a fourth electrolyte, and adding BF 3 ·Et 2 O into the third electrolyte; Firstly, injecting the third electrolyte into the shell and performing a first formation process; And then injecting the fourth electrolyte into the shell and performing a second formation process.
  10. 10. The method according to claim 9, wherein a total injection amount of the third electrolyte and the fourth electrolyte is 110% to 130% of a theoretical injection amount of the battery cell, and the injection amount of the third electrolyte is 80% to 90% of the total injection amount.
  11. 11. The method of producing a battery cell according to claim 9, wherein a mass ratio of BF 3 ·Et 2 O to the fourth electrolyte is (0.1 to 0.5): 1000.
  12. 12. The method according to claim 1, wherein the solvent of the first electrolyte is one or more selected from the group consisting of ethylene carbonate, propylene carbonate and fluoroethylene carbonate, and the diluent is one or more selected from the group consisting of methylethyl carbonate, diethyl carbonate, 1, 2-tetrafluoroethyl-2, 3-tetrafluoropropyl ether.
  13. 13. The method for producing a battery cell according to claim 1, wherein the particle diameter D50 of the h-BN is 450nm to 550nm.
  14. 14. The method for producing a battery cell according to claim 1, wherein the dispersion concentration of the fluorinated h-BN in the second electrolyte is 0.2mg/L to 0.5mg/L.
  15. 15. A battery cell prepared by the method for manufacturing a battery cell according to any one of claims 1 to 14, comprising: the lithium ion battery comprises a shell, and a positive plate, a diaphragm, a negative plate and electrolyte which are arranged in the shell, wherein the diaphragm is arranged between the positive plate and the negative plate.
  16. 16. A battery device comprising the battery cell of claim 15, wherein the battery device comprises one or more of a battery module, a battery pack, and an energy storage battery.
  17. 17. An electrical device, characterized in that it comprises a battery device according to claim 16, the battery device is used for providing electric energy.
  18. 18. An energy storage device comprising the battery device of claim 16 for storing electrical energy.

Description

Battery cell, manufacturing method thereof, battery device, power utilization device and energy storage device Technical Field The present application relates to the field of batteries, and in particular, to a battery cell, a manufacturing method thereof, a battery device, an electric device, and an energy storage device. Background Lithium metal batteries are known as "holy cup" battery technology because of their extremely high theoretical specific capacity (3860 mAh/g) and lowest electrochemical potential (-3.04vvs. She) and have an irreplaceable position in next generation high energy density energy storage systems. With the continuous increase of the requirements of electric vehicles on the endurance mileage and the development of the miniaturization trend of portable electronic devices, the development of battery systems with energy densities exceeding 500Wh/kg has become an urgent need. The lithium metal battery can improve the energy density of the battery by 50% -100% by adopting the lithium metal cathode to replace the graphite cathode, and especially when the lithium metal battery is combined with high-voltage anode materials (such as 4.6V grade nickel-rich ternary materials and 4.8V grade lithium-rich manganese-based materials), the lithium metal battery is expected to realize the ultra-high energy density of 600 Wh/kg-800 Wh/kg. However, lithium metal batteries face more serious technical challenges under high-pressure working conditions, and the high-pressure environment accelerates electrolyte decomposition and interfacial side reactions, which results in more prominent instability problems of the solid electrolyte interfacial film on the lithium metal surface. In the repeated charge and discharge process, the volume change and the uneven deposition dissolution behavior of lithium metal can lead to the rupture and regeneration of an SEI film, so that electrolyte and lithium metal are consumed to reduce coulomb efficiency, and potential safety hazards can be caused by the fact that dendrite growth penetrates through a diaphragm. Therefore, constructing a lithium metal negative electrode interface protection layer which stably works under high-pressure conditions is a key technical bottleneck for realizing the industrialization of lithium metal batteries. Disclosure of Invention The application provides a battery monomer, a manufacturing method thereof, a battery device, an electricity utilization device and an energy storage device, which are at least beneficial to remarkably improving the cycle stability and the safety performance of a lithium metal battery under a high-pressure condition. In one aspect, the present application provides a method for manufacturing a battery cell, including: providing a substrate, and depositing h-BN on the substrate; Carrying out fluorination treatment on the h-BN so as to enable B atoms in the h-BN and F atoms to form B-F covalent bonds; Stripping the h-BN from the substrate to obtain fluorinated h-BN; preparing a first electrolyte, wherein the first electrolyte comprises lithium salt, an additive, a diluent and a solvent; dispersing the fluorinated h-BN into the first electrolyte to obtain a second electrolyte, wherein the second electrolyte comprises lithium nitrate; Providing a positive plate, a negative plate and a diaphragm, sequentially laminating the positive plate, the diaphragm and the negative plate, and placing the positive plate, the diaphragm and the negative plate into a shell after winding or lamination treatment; and injecting the second electrolyte into the shell, and performing a formation process to obtain a battery monomer. Optionally, in the fluorinated h-BN, the atomic ratio of F atoms, B atoms and N atoms is (0.2-0.8): 1:1. Optionally, the h-BN is subjected to functional modification before being subjected to fluorination treatment, wherein the h-BN is firstly placed in a UV-O 3 cleaning machine to enable the h-BN to be grafted with-OH and/or-COOH, and then the h-BN is added into an amino-containing coupling agent to enable the-OH and/or-COOH to form Si-O bonds. Optionally, the first electrolyte comprises lithium nitrate, or the step of dispersing the fluorinated h-BN into the first electrolyte comprises: Dispersing the fluorinated h-BN into a mixed solution of lithium nitrate and hexafluoroisopropanol; Displacing the fluorinated h-BN into an intermediate solvent with a boiling point lower than 100 ℃ by adopting a gradient dilution method; The intermediate solvent in which the fluorinated h-BN is dispersed is added dropwise to the first electrolyte. Optionally, after dropping the intermediate solvent in which the fluorinated h-BN is dispersed into the first electrolyte, a rotary evaporation treatment is performed to remove the intermediate solvent. Optionally, the intermediate solvent is selected from one or more of dimethyl carbonate, acetonitrile and tetrahydrofuran. Optionally, the concentration of the lithium nitrate in the mixed so