▎ 摘 要
NOVELTY - Preparing microcrystalline graphite-doped graphene negative electrode material involves dividing the same batch of natural microcrystalline graphite powder, according to the particle size, dividing into three parts of powder M1, M2 and M3 with different particle sizes, pre-treating the powder M2 obtained to obtain M2', placing M1 obtained under the protection of inert gas, M2 'obtained S2 and M3 into different graphitizing furnaces, heating, holding and cooling. The graphitization is performed to obtain three kinds of graphitized powders. The corresponding three powders obtained is grounded by graphitizing M1, M2 'and M3 obtained according to the weight ratio of 1:8:1-8:1:1 to obtain a mixed powder M0. USE - Method for preparing microcrystalline graphite-doped graphene negative electrode material used for a lithium ion battery. ADVANTAGE - The method enables to prepare microcrystalline graphite-doped graphene negative electrode material has high reversible capacity, first capacity reach 367.9 mAh/g, good circulation stability, keeps the 362.6 mAh/g at 1500 cycles, good high-rate discharge capacity, capacity in the range of 500-800mA/g current density provides 376-358 mAh/g. DETAILED DESCRIPTION - Preparing microcrystalline graphite-doped graphene negative electrode material involves dividing the same batch of natural microcrystalline graphite powder, according to the particle size, dividing into three parts of powder M1, M2 and M3 with different particle sizes, pre-treating the powder M2 obtained to obtain M2', placing M1 obtained under the protection of inert gas, M2 'obtained S2 and M3 into different graphitizing furnaces, heating, holding and cooling. The graphitization is performed to obtain three kinds of graphitized powders. The corresponding three powders obtained is grounded by graphitizing M1, M2 'and M3 obtained according to the weight ratio of 1:8:1-8:1:1 to obtain a mixed powder M0, added pitch and graphene oxide powder to M0 to mix, merging the materials obtained. The fused material is carbonized through the three processes of heating, heat preserved and cooled. The cooled carbonized material is passed through a 300 mesh sieve, taken the sieve, and demagnetized by a demagnetizing machine to obtain final product.