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CN-122000475-A - Battery cell, battery device and electricity utilization device

CN122000475ACN 122000475 ACN122000475 ACN 122000475ACN-122000475-A

Abstract

The application discloses a battery cell, a battery device and an electricity utilization device in a first aspect of the application, which provides a battery cell, comprising a negative electrode plate, an electrolyte, a battery cell and a battery cell, wherein the negative electrode plate comprises a negative electrode current collector, wherein the electrolyte comprises sodium salt and an inert solvent, and the inert solvent comprises at least one of compounds shown in a formula 1 and/or a formula 2; wherein a is 1, 2, 3 or 4; Wherein b is 1 or 2, n 1 、n 2 is 1,2 or 3, respectively, independently, and n 1 and n 2 are not 1 at the same time. Therefore, the problem of gas production of the battery monomer in the using and storing processes can be effectively relieved, and the cycle performance and the storage performance of the battery monomer are improved.

Inventors

  • LI XIAOLONG
  • GUO BINGKUN
  • ZHANG XINXIN
  • CHEN SHIGANG
  • YAO SHIKANG
  • LIU BEN
  • LIN WENGUANG
  • DENG YUANYUAN
  • ZHOU QICHENG

Assignees

  • 宁德时代新能源科技股份有限公司

Dates

Publication Date
20260508
Application Date
20241107

Claims (20)

  1. 1. A battery cell, comprising: an electrolyte comprising a sodium salt and an inert solvent, wherein the inert solvent comprises at least one of the compounds shown in formula 1 and/or formula 2; wherein a is 1, 2, 3 or 4; Wherein b is 1 or 2, n 1 、n 2 is 1, 2 or 3, respectively, independently, and n 1 and n 2 are not 1 at the same time.
  2. 2. The battery cell of claim 1, wherein the inert solvent comprises at least one of ethylene glycol di-t-butyl ether, diethylene glycol di-t-butyl ether, triethylene glycol di-t-butyl ether, tetraethylene glycol di-t-butyl ether, ethylene glycol isopropyl t-butyl ether, ethylene glycol diisopropyl ether, ethylene glycol isopropyl ether, diethylene glycol isopropyl t-butyl ether, diethylene glycol diisopropyl ether, diethylene glycol isopropyl ether.
  3. 3. The battery cell of claim 2, wherein the inert solvent comprises at least one of ethylene glycol di-t-butyl ether, diethylene glycol di-t-butyl ether.
  4. 4. The battery cell of any one of claims 1-3, wherein the sodium salt comprises at least one of sodium perchlorate, sodium tetrafluoroborate, sodium hexafluorophosphate, sodium hexafluoroarsenate, sodium trifluoroacetate, sodium tetraphenylborate, sodium trifluoromethylsulfonate, sodium bis (fluorosulfonyl) imide, and sodium bis (trifluoromethylsulfonyl) imide.
  5. 5. The battery cell of any one of claims 1-4, wherein the inert solvent comprises 7-77% by mass based on the total mass of the electrolyte.
  6. 6. The battery cell of claim 5, wherein the inert solvent comprises 10% -30% by mass based on the total mass of the electrolyte.
  7. 7. The battery cell of any one of claims 1-5, wherein the sodium salt comprises 3-40% by mass based on the total mass of the electrolyte.
  8. 8. The battery cell of claim 7, wherein the sodium salt comprises 5-30% by mass based on the total mass of the electrolyte.
  9. 9. The battery cell of any one of claims 1-8, wherein the electrolyte further comprises a complexing solvent comprising at least one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1, 3-dioxolane, ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, methylethyl carbonate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethylene propyl carbonate, fluoroethylene carbonate, gamma-butyrolactone, 1, 3-propane sultone, methyl propionate, methyl butyrate, ethyl acetate, ethyl propionate, propyl propionate, ethyl butyrate, dimethyl sulfoxide.
  10. 10. The battery cell of claim 9, wherein the coordinating solvent comprises at least one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol dimethyl ether.
  11. 11. The battery cell according to claim 9 or 10, wherein the complexing solvent comprises 20-90% by mass based on the total mass of the electrolyte.
  12. 12. The battery cell of claim 11, wherein the coordinating solvent comprises from 30% to 80% by mass based on the total mass of the electrolyte.
  13. 13. The battery cell of any one of claims 1-12, wherein the electrolyte further comprises an ether additive comprising a C 2 -C 7 fluoroalkyl ether species.
  14. 14. The battery cell of claim 13, wherein the battery cell comprises a plurality of cells, the C 2 -C 7 fluoroalkyl ether substances comprise 1, 2-tetrafluoroethyl methyl ether, 2, 3-tetrafluoropropyl methyl ether, 1, 2-tetrafluoroethyl-2, 2-trifluoroethyl ether, bis- (2, 2-trifluoroethyl) ether, 1, 2-tetrafluoroethyl-2, 3-tetrafluoropropyl ether methyl nonafluorobutyl ether, bis- (1, 2-tetrafluoroethyl) ether, difluoromethyl-2, 2-trifluoroethyl ether, 1, 3-hexafluoro-2 (fluoromethoxy) propane, 1,2, 3-pentafluoropropyl-2, 2-trifluoroethyl ether methyl nonafluorobutyl ether, bis- (1, 2-tetrafluoroethyl) ether, difluoromethyl-2, 2-trifluoroethyl ether 1, 3-hexafluoro-2 (fluoromethoxy) propane, 1,2, 3-pentafluoropropyl-2, 2-trifluoroethyl ether.
  15. 15. The battery cell according to claim 13 or 14, wherein the ether additive is present in an amount of 0.1-4% by mass based on the total mass of the electrolyte.
  16. 16. The battery cell of claim 15, wherein the ether additive is present in an amount of 0.5% -3% by mass based on the total mass of the electrolyte.
  17. 17. The battery cell of any one of claims 1-16, wherein the electrolyte has an ionic conductivity of greater than or equal to 0.5mS/cm.
  18. 18. The battery cell of any one of claims 1-17, further comprising a positive electrode sheet comprising a positive electrode current collector and a positive electrode active material layer on at least one side of the positive electrode current collector, the positive electrode active material layer comprising a positive electrode active material comprising at least one of a sodium-containing polyanion compound, a sodium-containing layered oxide.
  19. 19. The battery cell of claim 18, wherein the positive electrode active material comprises a sodium-containing polyanion compound.
  20. 20. The battery cell of any one of claims 1-19, wherein the battery cell is a negative sodium-free battery cell.

Description

Battery cell, battery device and electricity utilization device Technical Field The application relates to the field of batteries, in particular to a battery cell, a battery device and an electric device. Background Currently, lithium ion batteries occupy the core of power batteries. Along with the gradual expansion of the application of the lithium ion battery in consumer electronics, electric automobiles, energy storage and other markets, the lithium ion battery also faces great challenges, such as the increasingly shortage of lithium resources, the continuous rising of upstream material prices, the delay of the development of a recycling technology, the low recycling rate of old batteries and the like. Sodium ion batteries are paid attention to gradually because the earth has high enough sodium element abundance, the sodium ion batteries can realize charge and discharge by utilizing the deintercalation process of sodium ions between the anode and the cathode, and the sodium ion batteries have the advantages of far more abundant storage than lithium, wider distribution, far lower cost than lithium and important strategic positions in application fields with high cost requirements, such as energy storage and the like. However, the existing sodium ion battery still has more problems to be solved in the application aspect. It should be noted that the foregoing statements are merely to provide background information related to the present disclosure and may not necessarily constitute prior art. Disclosure of Invention In a first aspect of the application, the application provides a battery cell, which comprises a negative electrode plate, an electrolyte and a battery cell, wherein the negative electrode plate comprises a negative electrode current collector, the electrolyte comprises sodium salt and an inert solvent, and the inert solvent comprises at least one of compounds shown in a formula 1 and/or a formula 2; wherein a is 1, 2, 3 or 4; Wherein b is 1 or 2, n 1、n2 is 1, 2 or 3, respectively, independently, and n 1 and n 2 are not 1 at the same time. Therefore, the problem of gas production of the battery monomer in the using and storing processes can be effectively relieved, and the cycle performance and the storage performance of the battery monomer are improved. In some embodiments, the inert solvent comprises at least one of ethylene glycol di-t-butyl ether, diethylene glycol di-t-butyl ether, triethylene glycol di-t-butyl ether, tetraethylene glycol di-t-butyl ether, ethylene glycol isopropyl t-butyl ether, ethylene glycol diisopropyl ether, ethylene glycol isopropyl ether, diethylene glycol isopropyl t-butyl ether, diethylene glycol diisopropyl ether, diethylene glycol isopropyl ether. Therefore, the side reaction between sodium metal and electrolyte can be effectively inhibited, and the cycle performance and storage performance of the battery monomer are improved. In some embodiments, the inert solvent comprises at least one of ethylene glycol di-t-butyl ether, diethylene glycol di-t-butyl ether. Thereby, the occurrence of side reactions between sodium metal and the electrolyte can be further suppressed. In some embodiments, the sodium salt comprises at least one of sodium perchlorate, sodium tetrafluoroborate, sodium hexafluorophosphate, sodium hexafluoroarsenate, sodium trifluoroacetate, sodium tetraphenylborate, sodium trifluoromethylsulfonate, sodium bis (fluorosulfonyl) imide, and sodium bis (trifluoromethylsulfonyl) imide. Thus, the electrochemical window can be improved, the occurrence of side reactions can be suppressed, and more uniform sodium metal deposition can be promoted. In some embodiments, the inert solvent comprises 7% to 77% by mass based on the total mass of the electrolyte. Thereby, the inert solvent can suppress the occurrence of side reactions between sodium metal and the electrolyte solvent. In some embodiments, the inert solvent comprises 10% to 30% by mass based on the total mass of the electrolyte. In some embodiments, the sodium salt comprises 3% to 40% by mass based on the total mass of the electrolyte. Thus, more active sodium ions can be provided. In some embodiments, the sodium salt comprises 5% to 30% by mass based on the total mass of the electrolyte. In some embodiments, the electrolyte further includes a complexing solvent including at least one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1, 3-dioxolane, ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, methylethyl carbonate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, fluoroethylene carbonate, γ -butyrolactone, 1, 3-propane sultone, methyl propionate, methyl butyrate, ethyl acetate, ethyl propionate, propyl propionate, ethyl butyrate, dimethyl sulfoxide. Thereby being beneficial to the full dissolution of sodium salt in the el