The present disclosure relates to a kind of
porous carbon material and its preparation method,
silicon-carbon composite negative material and application.The preparation method includes the following steps: (1)
organic matter precursor is dispersed in
solvent, then mixed with alkali source and crosslinking agent,
drying, obtain pre-treatment product;(2) pre-treatment product is activated and carbonized, to obtain the
porous carbon material.In the preparation method provided in the present disclosure, by pre-treatment and subsequent activation and
carbonization, on the one hand, the content of
oxygen in the product can be controlled, on the other hand, the state of
oxygen in the surface functional groups of the product can also be adjusted, so that a large number of uniform deposition
layers can be formed during the deposition of elemental
silicon on the surface of the
porous carbon material;And the production of
silicon oxide and
silicon carbide can be effectively controlled, so as to improve the silicon-carbon composite negative material formed has initial
coulomb efficiency, capacity, cycle performance stability.