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

• Carbon-coated Li3VO4 embedded in expanded graphite has been synthesized at one step.
• High electronic conductivity and mechanical stability are obtained.
• Rate and cycling performance largely improved as for 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).