The present invention discloses a
lithium iron phosphate-
carbon nanotube (LiFePO4-CNTs)
composite material. The
composite material comprises LiFePO4 particles, a nano-
carbon layer and CNTs, wherein the nano-
carbon layer is positioned outside the LiFePO4 particles, and the CNTs grow in the nano-
carbon layer in an in situ growth manner by a
chemical vapor deposition (CVD) process. In addition, the present invention further discloses a preparation method for the
composite material. The method comprises: uniformly mixing and
coating the prepared LiFePO4 precursor
powder, a catalyst and
liquid carbon source to prepare into the
slurry; adopting a spraying feeding device to convey the
slurry to a high-temperature reaction furnace to form a floating CVD process; carrying out heat insulation
calcination for the resulting mixture so as to complete the treatments of
granulation of the LiFePO4 precursor, in situ growth and
coating of the CNTs and synthesis
sintering of the LiFePO4 in one step, such that the uniform nano-carbon layer and the CNTs are formed on the surfaces of the LiFePO4 particles. In addition, the present invention further discloses an application of the composite material in battery preparation. According to the composite material of the present invention, the nano-carbon layer and the CNTs have good
crystallization, the total carbon content is low, the electrical
conductivity and the specific capacity are high so as to substantially increase the rate performance.