NEGATIVE ELECTRODE MATERIAL FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY, AND PREPARATION METHOD THEREFOR

Disclosed in the present invention are a negative electrode material for a nonaqueous electrolyte secondary battery, and a preparation method therefor. The negative electrode material comprises a porous secondary particle and a hole sealing layer on the surface of the secondary particle, and the secondary particle is formed by aggregation of primary particles made of a silicon-based material. The negative electrode material is characterized in that: the primary particles are loaded on a three-dimensional network body, and the primary particles are connected by means of the three-dimensional network body; the three-dimensional network body is formed of a carbon nanomaterial coated with a fast ionic conductor on the surface. The negative electrode material provided by the present invention exhibits extremely low expansivity and higher electrical conductivity and ionic conductivity; when the negative electrode material is applied to the secondary battery, the battery has excellent rate capability and cycle performance. The preparation method in the present invention is simple and easy to implement and low in costs, and is suitable for large-scale production.