Recent advances on low-Co and Co-free high entropy layered oxide cathodes for lithium-ion batteries

As the price of the precious metal cobalt continues to rise, there is an urgent need for a cobalt-free or low-cobalt electrode material to reduce the cost of lithium-ion batteries, which are widely used commercially, while maintaining their performance as much as possible. With the introduction of the new concept of high entropy (HE) materials into the battery field, low cobalt and cobalt free HE novel lithium-ion batteries have attracted great attention. It possesses important research value to use HE materials to reduce the use of cobalt metal in electrode materials. In this perspective, the comparison between the new cathode materials of low cobalt and cobalt-free HE lithium-ion battery and traditional cathode materials and the latest progress in maintaining structural stability and conductivity are introduced. It is believed that low cobalt and cobalt-free and HE layered oxides can be used to replace the function of cobalt in the cathode materials of lithium-ion batteries. Finally, the future research directions and the synthesis method of HE cathode materials for lithium-ion batteries are also discussed.