An inactive metal supported oxide cathode material with high rate capability for sodium ion batteries

Abstract Sodium ion batteries (SIBs) are considered to be one of the most promising large-scale energy storage systems. However, the lack of high-performance cathode materials has challenged its development. Herein, a new P2-type Na0.8Li0.1Mn0.6Ni0.2Cu0.1O2 cathode material is designed and synthesized via coprecipitation method for the first time. As inert elements, Li play the role of structural supporting site in prismatic lattice to reinforce overall crystals, so that the material maintains high structural stability in the process of Na+ intercalation/deintercalation. The charge and discharge tests exhibit that it delivers a reversible capacity of 135.1 mA h g−1 at 0.1C with high retention of 83.1% after 100 cycles. Besides, it still keeps a retention of 81.7% after 400 cycles at 1 A g−1 with initial capacity of 84.7 mA h g−1. The large lattice spacing, monophasic reaction and high sodium diffusivity are the guarantee of excellent electrochemical performance. Therefore, this work is significant for the development of promising new Na ion insertion cathode.