SILICON-BASED COMPOSITE NEGATIVE ELECTRODE MATERIAL, PREPARATION METHOD THEREFOR, AND ENERGY STORAGE DEVICE

摘要

Embodiments of the present invention provide a silicon-based composite anode material, including a silicon-based material core and a coating layer coated on a surface of the silicon-based material core, where the coating layer includes a first coating layer disposed on the surface of the silicon-based material core and a second coating layer disposed on a surface of the first coating layer, the first coating layer includes a two-dimensional quinone-aldehyde covalent organic framework material, and the second coating layer includes a fast ion conductor material. With super toughness and an ordered pore structure, the first coating layer can effectively absorb mechanical stress generated by expansion of the silicon-based material core and ensure integrity of the coating layer, and has high electrical conductivity and ionic conductivity, thereby effectively enhancing effects of electron conduction and ion conduction of the coating layer. The second coating layer is relatively rigid, can maintain structural stability of the entire material during silicon expansion and contraction, and effectively alleviates volume expansion. The embodiments of the present invention further provide a method for preparing the silicon-based composite anode material and an energy storage device that includes the silicon-based composite anode material.