Stabilized electrode phase by prelithiating V2O5 cathode materials for high-specific energy thermal batteries

Vanadium pentoxide (V2O5) is an attractive high-energy cathode material for thermal batteries but is limited by the high solubility and tendency to react with halogenic molten salt. LixV2O5 (0 < x ≤ 1) are expected to take the place of V2O5 as the promising cathode materials in thermal batteries. In this work, LixV2O5 were successfully synthesized by the high-efficiency and low-cost method, which uses the molten salt as lithium source and through a brief-time sintered process (900 °C for 15 s). LixV2O5/molten salt electrode with CNTs conductive agent exhibits an original discharge voltage with 2.51 V and a specific capacity up to 309.46 mA h g−1. The high chemical stabilization between LixV2O5 and molten salt which could increase interfacial structure stabilization and improve the transmission rate of Li+. Besides, CNTs could build the continuous electron transport channels in active cathode inter-particles and improve the utilization rate of LixV2O5. This paper not only prepares the LixV2O5 cathode materials with high specific capacity via a simple method, but also provides insights into the phase evolution process of V2O5 based cathode electrodes during discharge process of thermal batteries.