Method for in-situ preparation of porous silicon-carbon composite negative electrode material

• Main Authors: ZHAO DONGNI, CUI XIAOLING, DONG HONG, SONG RU, WANG PENG, FU XIAOLAN, LI CHUNLEI, LIANG WENBIAO, DING HAO, WEI YUAN, LI SHIYOU
• Format: Patent
• Language: Chinese; English
• Published: 11.09.2020
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMISTRY; COMPOUNDS THEREOF; ELECTRICITY; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

The invention relates to a method for in-situ preparation of a porous silicon-carbon composite negative electrode material. The method comprises the following steps of: (1) ball-milling dispersion: carrying out ball-milling mixing on a low-melting-point soluble inorganic salt, nano silicon or micro-nano silicon, and carrying out inert gas replacement in a ball-milling tank; (2) high-temperature melting: carrying out inert environment high-temperature melting on the material obtained in the step (1) to form a molten mixture, and controlling the melting temperature at 1450-1800DEG C and the heating rate at 5-10DEG C/min; (3) ball-milling coating: carrying out high-energy ball-milling mixing on the molten mixture obtained in step (2) and a carbon precursor or a carbon material in proportion,and performing inert gas replacement in the ball milling tank; (4) high-temperature carbonization: carrying out high-temperature carbonization on the mixed material obtained in step (3), and controlling the carbonization temp