A high-voltage honeycomb-layered Na4NiTeO6 as cathode material for Na-ion batteries

We report a high-voltage Na4NiTeO6 cathode material for Na-ion batteries. It delivers 111 mAh g−1 at 0.1 C with 87% contribution from the inductive effect at the voltage beyond 3.5 V. With addition of fluoroethylene carbonate, stable fluorine-containing solid electrode interface is formed, which significantly improve its cyclic performance. Our results provide insights into designing sodium layered cathode materials with high voltage, which will benefit for the development of high energy Na-ion batteries.