A dual strategy of Na/vacancy disorder and high Na to construct a P2-type cathode for high-stability sodium-ion batteries.

P2-type layered oxides are widely regarded as highly promising contenders for cathode materials in sodium-ion batteries. However, the occurrence of severe reactive phase transitions hinders satisfactory cycling stability and rate performance, thereby imposing limitations on their practical application. Here we prepared P2-type NaNiMgMnO cathode materials using the agar gel approach.