A lamellar V 2 O 3 @C composite for aluminium-ion batteries displaying long cycle life and low-temperature tolerance.

Rechargeable aluminum-ion (Al-ion) batteries have important potential for fast charging and safe energy-storage systems. Here, we develop a composite composed of lamellar V 2 O 3 @C nanosheets, which displays high electrochemical properties as an Al-ion battery cathode. The unique structure is conducive to the rapid insertion and release of Al 3+ ions, electrolyte infiltration, and improved conductivity. After cycling 500 times, the capacity exceeds 242.5 mA h g -1 . Under a low temperature of -10 °C, the capacity remains 150.8 mA h g -1 , and the Coulombic efficiency is higher than 98.8%. The V 2 O 3 @C also exhibits a good reversibility verified by using ex situ X-ray powder diffraction patterns, while the constant current intermittent titration technology shows a low reaction barrier, which indicates that the lamellar composite presented here could find significant applications for engineering many high-performance energy-storage systems.