The invention discloses a preparation method for a high-performance three-dimensional 
carbon nanotube composite negative 
electrode material. The preparation method comprises: by taking a carboxylated 
carbon nanotube as a three-dimensional network framework and taking a high-capacity material subjected to layer by layer self-
assembly and modification as an active substance, uniformly mixing the 
carbon nanotube with the active substance under the action of 
electrostatic attraction; and then performing in-situ 
coating by taking a mixed element-containing N or S-
doped carbon source as a three-dimensional 
coating layer, and performing high-
temperature treatment to obtain the high-performance three-dimensional carbon 
nanotube composite negative 
electrode material. The invention furthermore discloses the high-performance three-dimensional carbon 
nanotube composite negative 
electrode material and an application thereof. According to the preparation method, the cycle performance of the active substance is remarkably improved, and the capacity of the 
composite material can be controllably adjusted by controlling a ratio of the carbon 
nanotube to the active substance. In addition, a 
solvent used in the method is water, so that the method is environmentally-friendly, good in 
repeatability and low in cost, and has relatively 
high potential of large-scale application and good industrialized prospects.