CARBON MATERIAL, SILICON-CARBON NEGATIVE ELECTRODE MATERIAL, AND PREPARATION METHOD FOR AND USE OF SILICON-CARBON NEGATIVE ELECTRODE MATERIAL

The present disclosure relates to the technical field of battery negative electrode materials, and disclosed are a carbon material, a silicon-carbon negative electrode material, and a preparation method for and a use of the silicon-carbon negative electrode material. In the negative electrode material, silicon is distributed within pores of a porous substrate, and the volume expansion of silicon in a lithium deintercalation process is suppressed by using the pore structure of the porous substrate, thereby improving the cycle performance of the negative electrode material. The silicon-carbon composite material exhibits high sphericity, avoids poor compression resistance due to numerous edges and corners during rolling, and can mitigate the problems of continuous formation of solid electrolyte interface (SEI) films, reduced capacity and poor cycle performance caused by low strength. Porous carbon is prepared using a nanoscale carbon nanotube, facilitating improvement of the electrical conductivity of the porous carbon; and in addition, a tin or germanium element doped into the negative electrode material facilitates deintercalation of lithium ions by lowering the energy barrier of lithium ion transition, thereby improving the initial coulombic efficiency.