Low temperature synthesis of nickel-based layered cathodes

Abstract We investigated low temperature synthesis process of nickel-based layered cathodes. In the case of LiNiO2 synthesis, the oxidation process of Ni2+ to Ni3+ requires a high temperature of >500 °C. On the other hand, the Na2O2 formation enables the synthesis of NaNiO2 at 300 °C, suggesting that an additional oxidation process of nickel is required for the successful synthesis of the layered LiNiO2. The layered LiNiO2 is synthesized at 300 °C using NiOOH as the starting material. Both the charge-discharge profiles and X-ray absorption spectroscopy suggest partial reduction of the Ni3+ species under hydroflux conditions, resulting in the formation of a disordered rocksalt domain.