A hierarchical structure of carbon-coated Li3VO4 nanoparticles embedded in expanded graphite for high performance lithium ion battery

A hierarchical structure of carbon-coated Li3VO4 nanoparticles homogeneously embedded in expanded graphite was successfully synthesized by a facile and scalable sol gel method. In the constructed architecture, high electronic conductivity of expanded graphite serves as a loading carrier, enabling the fast transmission of electronics. The thin outside carbon shells protect the Li3VO4 nanoparticles from direct exposure to the electrolyte and mitigate unwanted interfacial side reactions. As a consequence, the hybrid material exhibits greatly enhanced cycle and rate capability compared with pristine Li3VO4: a reversible gravimetric capacity of 405 mAh g(-1) obtained at 100 mA g(-1) with 89% retention after 200 cycles, and 205.5 mAh g(-1) obtained after 2000 cycles at a heavy current of 2000 mA g(-1), as well as an remarkable rate performance of 62.7% capacity maintaining at 6400 mA g(-1) (vs. 100 mA g(-1)). (C) 2015 Elsevier B.V. All rights reserved.