Synthesis of LiFePO4in situ vapor-grown carbon fiber (VGCF) composite cathode material via microwave pyrolysis chemical vapor deposition

Abstract

One of the most important factors that limits the use of LiFePO4 as cathode material for lithium ion batteries is its low electronic conductivity. In order to solve this problem, LiFePO4in situ vapor-grown carbon fiber (VGCF) composite cathode material has been prepared in a single step through microwave pyrolysis chemical vapor deposition. The phase, microstructure, and electrochemical performance of the composites were investigated. Compared with the cathodes without in situ VGCF, the initial discharge capacity of the composite electrode increases from 109 to 144 mA h g-1 at a 0. 5-C rate, and the total electric resistance decreases from 538 to 66 Ω. The possible reasons for these effects are proposed. © 2011 Science China Press and Springer-Verlag Berlin Heidelberg.