CN-116605864-B - Preparation method of phenolic resin-based sodium ion battery hard carbon anode material

Abstract

The invention belongs to the field of sodium ion batteries, in particular to a preparation method of a phenolic resin-based sodium ion battery hard carbon negative electrode material, which adopts a phenolic resin foaming material as a hard carbon precursor material, and preparing the phenolic resin-based sodium ion battery hard carbon anode material through carbonization, pore adjustment and carbon deposition, thereby obtaining the phenolic resin-based hard carbon anode material with high capacity and high first coulomb efficiency. The invention uses carbide high temperature burning under inert gas to achieve large aperture shrinkage method, forms graphitized structure change of hard carbon material, enlarges pores and closes pores to realize carbon atom recombination by pore adjusting mode.

Inventors

• YANG JIANQIANG
• ZHOU JIJUN

Assignees

• 钠鑫(浙江)能源科技有限公司

Dates

Publication Date

20260512

Application Date

20230430

Claims (2)

1. 1. A preparation method of a phenolic resin-based sodium ion battery hard carbon anode material is characterized by comprising the following steps: Step 1, smashing phenolic aldehyde resin foaming materials, namely screening the phenolic aldehyde resin foaming materials, removing impurities, and then mechanically smashing, demagnetizing and grading to obtain precursor powder particles; Step 2, carbonizing the crushed phenolic resin foaming material at high temperature in an inert atmosphere, namely placing the crushed phenolic resin foaming material into a furnace, and heating and carbonizing the phenolic resin foaming material under the protection of nitrogen; Step 3, adjusting holes of CO 2 and CO mixed gas, namely after the high-temperature carbonization technology, introducing CO 2 -CO mixed gas into the furnace, and adjusting holes of the hard carbon precursor; Step 4, carbon deposition, namely placing the hard carbon precursor subjected to pore adjustment into a converter furnace, introducing pore blocking agent under the protection of nitrogen, and keeping the furnace temperature at 300-400 ℃ for adsorption, and then cracking the pore blocking agent adsorbed on the carbon material at 800-950 ℃, so as to deposit pyrolytic carbon on the hard carbon material; step 5, detecting and packaging the prepared phenolic resin-based hard carbon anode material; The phenolic resin foaming material in the step 1 is from a thermosetting phenolic resin foaming plate or a phenolic resin heat insulation material, wherein the mechanical crushing adopts ball milling, the phenolic resin foaming material is prepared into powder particles with the particle size of less than 1000 meshes, and then the powder particles are subjected to demagnetizing and grading to enable precursor powder particles to be distributed at 5-13 mu m; the temperature in the step 2 is 800-1550 ℃ and the time is 6-12h; the proportion of CO 2 in the mixed gas in the step 3 is 85-90%, the introducing time of the mixed gas is 5-30min, and the temperature of the hole is 550-800 ℃; The pore plugging agent in the step 4 adopts dimethylbenzene, the flow is 50-60mL/min, the pressure is 0.03-0.04MPa, and the carbon deposition is mainly deposited in micropores and on the surfaces of powder particles.
2. 2. The method for preparing the phenolic resin based sodium ion battery hard carbon negative electrode material according to claim 1, wherein the phenolic resin based hard carbon negative electrode material in the step 4 is sieved and classified before detection, so that the powder particles D50 of the negative electrode material are distributed at about 4-10 microns.

Description

Preparation method of phenolic resin-based sodium ion battery hard carbon anode material Technical Field The invention belongs to the field of sodium ion batteries, and particularly relates to a preparation method of a phenolic resin-based sodium ion battery hard carbon anode material. Background The study of sodium ion batteries originated from the "rocking chair battery" proposed by Armand, france in 1979, and began contemporaneously with the study of lithium ion batteries. Sodium ion batteries develop very slowly in the next decade, even once near vacuum, due to the lack of suitable negative electrode materials. Until 2000, researchers have found hard carbon, which is a negative electrode material suitable for sodium ion batteries, so that the development of sodium ion batteries has turned over. Especially, after 2010, research results of sodium ion batteries are coming to blowout type growth, and industrialization progress is being promoted. However, the selection of the negative electrode material of the sodium ion battery is a great difficulty in realizing commercialization, and through screening, the hard carbon material becomes an ideal material for commercialization due to the advantages of large interlayer spacing, low cost, simple synthesis method, possibility of using renewable resources as precursors and the like. However, the traditional biomass has the problems of low carbon yield, low initial efficiency, controversial sodium storage mechanism, complex structure, difficulty in accurate control and the like, and influences the practical process. There is an urgent need in the industry to find precursors with high carbon yields and low cost. Disclosure of Invention Aiming at the problems in the prior art, the invention provides a preparation method of a hard carbon negative electrode material of a phenolic resin-based sodium ion battery, which solves the defects of the existing negative electrode hard carbon material and forms the hard carbon negative electrode material with high capacity and high first coulombic efficiency by means of carbonization, pore-regulation and carbon deposition. In order to achieve the technical purpose, the technical scheme of the invention is as follows: a preparation method of a phenolic resin-based sodium ion battery hard carbon anode material comprises the following steps: Step 1, smashing phenolic aldehyde resin foaming materials, namely screening phenolic resin foaming materials, removing impurities, mechanically smashing, demagnetizing and grading to obtain precursor powder particles, wherein the phenolic resin foaming materials are from phenolic resin foaming plates, phenolic resin heat-insulating materials and the like, the impurities are silt, dust, fibers and the like, the mechanical smashing is preferably ball milling, the phenolic resin foaming materials are prepared into powder with the particle size of less than 1000 meshes, and then the powder particles are demagnetized and graded to enable the precursor powder particles to be distributed at 5-13 mu m; step 2, carbonizing the crushed phenolic resin foaming material at high temperature in an inert atmosphere, namely placing the crushed phenolic resin foaming material into a furnace, and heating and carbonizing the crushed phenolic resin foaming material under the protection of nitrogen, wherein the temperature is 800-1550 ℃ and the time is 6-12h; Step 3, CO 2 and CO mixed gas hole adjustment, namely after the high-temperature carbonization technology, introducing CO 2 -CO mixed gas into the furnace, adjusting holes of the hard carbon precursor, wherein the proportion of CO 2 in the mixed gas is 85-90%, the introducing time of the mixed gas is 5-30min, and the temperature of the holes is 550-800 ℃, and a small amount of CO is added into the mixed gas, so that the oxidation speed can be effectively slowed down; Step 4, carbon deposition, namely placing a hard carbon precursor subjected to pore adjustment into a converter furnace, introducing pore plugging agent under the protection of nitrogen, keeping the furnace temperature at 300-400 ℃ for adsorption, then cracking the pore plugging agent adsorbed on a carbon material at 800-950 ℃, thereby depositing pyrolytic carbon on the hard carbon material, carrying out pore diameter adjustment on the hard carbon precursor to ensure that the diameter of ultra-micropores is mostly distributed in the range of 0.4-0.6nm, adopting dimethylbenzene as the pore plugging agent, and keeping the flow rate at 50-60mL/min and the pressure at 0.03-0.04MPa, wherein the carbon deposition is mainly deposited in micropores and on the surfaces of powder particles; And 5, detecting and packaging the prepared phenolic resin-based hard carbon anode material. Further, the phenolic resin-based hard carbon anode material in the step 4 is sieved and graded before detection, so that the powder particles D50 of the anode material are distributed at about 4-10 microns. From the above descri