Multiple-element composite material for negative electrodes, preparation method therefor, and lithium-ion battery having same

A multiple-element composite material for negative electrodes, a preparation method therefor, and a lithium-ion battery using the negative electrode material. The lithium-ion battery uses multiple-element composite material for negative electrodes has a core-shell structure containing multiple shell layers. The inner core consists of graphite and nano-active matter coating the surface of the graphite. The outer layers of the inner core are in order: the first shell layer is of an electrically conductive carbon material, the second shell layer is of a nano-active matter, and the third shell layer is an electrically conductive carbon material coating layer. The multiple-element composite material for negative electrodes of the present invention combines coating processing technology with surface composite modification and coating modification technology to successfully prepare a multiple-element composite material for negative electrodes having a core-shell structure containing multiple shell layers, and allows for high load and high dispersion for the nano-active matter, thereby substantially enhancing the material specific capacity, cycle performance, and initial efficiency. Additionally, the multiple-element composite material for negative electrodes of the present invention has high compacted density and good processing performance. The negative electrode material has simple preparation technique and low raw material cost, is environmentally friendly, and causes no pollution.