Rational Design and Synthesis of Li₃V₂(PO₄)₃/C Nanocomposites As High-Performance Cathodes for Lithium-Ion Batteries

Synthesis of cathode materials with high rates and long cycle life is critical to meet the demands of high-power lithium-ion battery applications. Batteries that can work at extreme low temperature conditions are also urgently needed. Herein, we report the rational design and synthesis of a novel lithium vanadium phosphate/carbon (Li 3 V 2 (PO 4 ) 3 /C) nanocomposite with a thin-layer amorphous carbon shell (∼4 nm) coating and a mesoporous KB carbon matrix. As expected, the Li 3 V 2 (PO 4 ) 3 /C nanocomposite demonstrates an excellent high-rate and long-term cycling performance as well as broad temperature adaptability. Even at a high rate of 16C, a high capacity of 102 mA h g –1 can be achieved. Importantly, the capacity retention is 99% after 1000 cycles and 94% after 2000 cycles when cycled at a rate of 6 C at room temperature in a voltage range of 3–4.3 V. Importantly, this nanocomposite can cycle at −30 °C for 500 cycles with a stable capacity. The excellent rate capability, stable cycling performance, and broad temperature adaptability suggest that the Li 3 V 2 (PO 4 ) 3 /C nanocomposite is a promising cathode for practical applications.