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CN-119208744-B - Preparation process of non-negative sodium metal battery and non-negative sodium metal battery

CN119208744BCN 119208744 BCN119208744 BCN 119208744BCN-119208744-B

Abstract

The invention provides a preparation process of a non-negative sodium metal battery and the non-negative sodium metal battery. The preparation process comprises the steps of preparing a positive plate, mixing an acrylic monomer, aromatic diamine and an initiator to obtain a first mixture, adding a graphene oxide solution to mix to obtain a second mixture, adding a liquid electrolyte and an ether substance to mix to the second mixture to obtain a third mixture, separating the positive plate and a negative current collector at intervals by adopting a separation film, assembling the positive plate and the negative current collector into a bare cell, packaging, pouring the third mixture, sealing, and heating and polymerizing to obtain the battery. The preparation process can effectively inhibit sodium dendrite, and can improve the cycle performance and low-temperature performance of the battery while maintaining the high capacity of the negative electrode-free sodium metal battery.

Inventors

  • ZHAO SIQI
  • HUANG YANG
  • ZHAO YOUMAN

Assignees

  • 东莞市创明电池技术有限公司

Dates

Publication Date
20260505
Application Date
20240913

Claims (9)

  1. 1. The preparation process of the negative electrode-free sodium metal battery is characterized by comprising the following steps of: (1) Preparing a positive plate; (2) Mixing an acrylic monomer, aromatic diamine and an initiator to obtain a first mixture, adding a graphene oxide solution to mix to obtain a second mixture, adding a liquid electrolyte and an ether substance to mix to obtain a third mixture; (3) Separating the positive plate and the negative current collector by adopting a separation film, assembling the positive plate and the negative current collector into a bare cell, packaging, pouring the third mixture and sealing; (4) And after heating and polymerizing, forming the liquid electrolyte, wherein the liquid electrolyte comprises sodium salt and a nonaqueous organic solvent, the sodium salt comprises at least one of sodium hexafluorophosphate, sodium difluoroborate, sodium tetrafluoroborate, sodium bisoxalato borate, sodium perchlorate, sodium hexafluoroarsenate, sodium bis (fluorosulfonyl) imide, sodium trifluoromethylsulfonate and sodium bis (trifluoromethylsulfonyl) imide, and the nonaqueous organic solvent comprises at least one of carbonate, carboxylate and lactone.
  2. 2. The process for preparing a negative electrode-free sodium metal battery according to claim 1, wherein the acrylic monomer comprises at least one of methyl methacrylate, ethyl methacrylate, methyl acrylate and ethyl acrylate, and the aromatic diamine comprises at least one of o-phenylenediamine, m-phenylenediamine and p-phenylenediamine.
  3. 3. The preparation process of the negative-electrode-free sodium metal battery according to claim 1, wherein the mass ratio of the acrylic acid ester monomer to the aromatic diamine is 1-2:1-2.
  4. 4. The process for preparing a negative electrode-free sodium metal battery according to claim 1, wherein the sum of the mass of the acrylic acid ester monomer and the mass of the aromatic diamine is m, the mass of the initiator is n, n/m is 0.001-0.010, and the initiator comprises at least one of azobisisobutyronitrile, azobisisoheptonitrile and dimethyl azobisisobutyrate.
  5. 5. The preparation process of the negative-electrode-free sodium metal battery according to claim 1, wherein the sum of the mass of the acrylic acid ester monomer and the mass of the aromatic diamine is m, the mass of the graphene oxide solution is p, the p/m is 10-90%, and the graphene oxide solution is an aqueous solution with the mass concentration of graphene oxide of 1.0-5.0 mg/ml.
  6. 6. The process for preparing a negative sodium metal-free battery according to claim 1, wherein the mass ratio of the liquid electrolyte to the second mixture is 5-50:50-95.
  7. 7. The process for preparing a negative-electrode-free sodium metal battery according to claim 1, wherein the sum of the mass of the acrylic ester monomer and the mass of the aromatic diamine is m, the mass of the ether substance is q, q/m is 0.01-0.10, and the ether substance comprises at least one of dimethyl ether, tetraethylene glycol dimethyl ether and diethylene glycol dimethyl ether.
  8. 8. The process for preparing the negative-electrode-free sodium metal battery according to claim 1, wherein the heating polymerization temperature is 50-80 ℃ and the time is 4-9 h.
  9. 9. The negative-electrode-free sodium metal battery prepared by the preparation process of any one of claims 1-8, wherein the negative-electrode-free sodium metal battery comprises a positive electrode plate, a separation film, a negative electrode current collector and a solid electrolyte, wherein the solid electrolyte is at least compounded on the surface of the negative electrode current collector.

Description

Preparation process of non-negative sodium metal battery and non-negative sodium metal battery Technical Field The invention relates to the technical field of material preparation, in particular to a preparation process of a negative-electrode-free sodium metal battery and the negative-electrode-free sodium metal battery. Background With the gradual expansion of the application of lithium ion battery technology in consumer electronics, electric automobiles, energy storage and other markets, the problem of insufficient lithium resources is also highlighted. Sodium-based batteries are attracting attention due to the earth's sufficiently high abundance of sodium elements, and have an important strategic position in application fields with high cost requirements for energy storage and the like. Because of the problems of low specific capacity and the like of the sodium ion battery, the large-scale application of the sodium ion battery is limited. The negative electrode-free sodium metal battery does not have any sodium ion embedded material at the negative electrode side, only has a negative electrode current collector, can work as the negative electrode end of the sodium metal battery after an initial charging process, thereby providing higher working voltage and remarkably improving the volume energy density and the mass energy density due to the reduction of the volume and the weight of the battery. However, the existing negative-electrode-free sodium metal battery has two main problems that firstly, due to the limited quantity of active sodium in the battery, SEI films are always broken and rebuilt due to consumption of sodium ions caused by volume change of deposited metal sodium, so that capacity attenuation is extremely fast, and secondly, in the process of repeated intercalation and deintercalation of sodium ions, the restraint of negative electrode materials is avoided, sodium ions easily present uneven deposition forms on a current collector, so that dead sodium is caused, and capacity exertion and coulombic efficiency of the negative-electrode-free battery are affected. Therefore, compared with an electrode with a negative electrode active material, the negative electrode current collector of the negative electrode-free sodium metal battery has the outstanding problem of sodium dendrite growth, and the battery has the problems of rapid capacity fading, low coulombic efficiency and the like. Therefore, a new negative electrode current collector or a negative electrode-free sodium metal battery is urgently needed to meet the requirements of a negative electrode-free sodium metal battery with high capacity and high safety performance, and simultaneously, sodium dendrite, cycle failure, coulombic efficiency and the like can be further improved. Disclosure of Invention The invention aims to provide a preparation process of a negative-electrode-free sodium metal battery and the negative-electrode-free sodium metal battery, wherein the preparation process can effectively inhibit sodium dendrite, and can improve the cycle performance and low-temperature performance of the battery while maintaining the high capacity of the negative-electrode-free sodium metal battery. In order to achieve the above object, the present invention provides a process for preparing a negative electrode-free sodium metal battery, comprising the steps of: (1) Preparing a positive plate; (2) Mixing an acrylic monomer, aromatic diamine and an initiator to obtain a first mixture, adding a graphene oxide solution to mix to obtain a second mixture, adding a liquid electrolyte and an ether substance to mix to obtain a third mixture; (3) Separating the positive plate and the negative current collector by adopting a separation film, assembling the positive plate and the negative current collector into a bare cell, packaging, pouring the third mixture and sealing; (4) And heating and polymerizing to obtain the final product. In the preparation process of the non-negative-electrode sodium metal battery, acrylic ester monomers and aromatic diamine are polymerized under the action of an initiator and heating, and part of acrylic ester monomers can reduce graphene oxide to obtain nitrogen-doped graphene serving as a framework, so that nitrogen-doped graphene hydrogel with a porous three-dimensional structure can be formed through heating polymerization and formation, and the low-temperature performance of the non-negative-electrode sodium metal battery can be improved. The ether substances exist in the graphene hydrogel and are compounded on the negative current collector to form an SEI film on the surface of the current collector, so that the consumption of sodium ions in the formation stage can be reduced, and the first coulomb efficiency is improved. The nitrogen doping provided by the aromatic diamine can generate active sites, can induce the uniform formation of sodium crystal nucleus, also avoids the consumption of sodium ions, and can impr