Hierarchical Carbon Decorated Li₃V₂(PO₄)₃ as a Bicontinuous Cathode with High‐Rate Capability and Broad Temperature Adaptability

Abstract

Developing rechargeable lithium ion batteries with fast charge/discharge rate, high capacity and power, long lifespan, and broad temperature adaptability is still a significant challenge. In order to realize the fast and efficient transport of ions and electrons during the charging/discharging process, a 3D hierarchical carbon‐decorated Li 3 V 2 (PO 4 ) 3 is designed and synthesized with a nanoscale amorphous carbon coating and a microscale carbon network. The Brunauer–Emmett–Teller (BET) surface area is 65.4 m 2 g −1 and the porosity allows for easy access of the electrolyte to the active material. A specific capacity of 121 mAh g −1 (91% of the theoretical capacity) can be obtained at a rate up to 30 C. When cycled at a rate of 20 C, the capacity retention is 77% after 4000 cycles, corresponding to a capacity fading of 0.0065% per cycle. More importantly, the composite cathode shows excellent temperature adaptability. The specific discharge capacities can reach 130 mAh g −1 at 20 C and 60 °C, and 106 mAh g −1 at 5 C and –20 °C. The rate performance and broad temperature adaptability demonstrate that this hierarchical carbon‐decorated Li 3 V 2 (PO 4 ) 3 is one of the most attractive cathodes for practical applications.