Tuning Cobalt‐Free Nickel‐Rich Layered LiNi0.9Mn0.1O2 Cathode Material for Lithium‐Ion Batteries

As the demand for high‐energy‐density batteries becomes more and more urgent, cathode materials of high‐energy lithium‐ion batteries have received widespread attention. LiNixCoyMn1‐x‐yO2 (NCM) ternary materials with high nickel and low cobalt content as well as a high cut‐off voltage are continually pursued. Here, a nickel‐rich cobalt‐free cathode material, LiNi0.9Mn0.1O2, was synthesized by using a co‐precipitation method to achieve a stable structure and excellent electrochemical performance. It shows a discharge specific capacity of 190 mAhg−1 in the first cycle at a rate of 0.2 C, and a capacity retention of 93 % over 150 cycles at 2.7–4.3 V. It also exhibits excellent electrochemical performance under high cut‐off voltage. The initial discharge specific capacity reaches 197.5 mAhg−1 at 0.2 C within 2.7 to 4.5 V, and the capacity retains 188.9 mAhg−1 after 100 cycles. The work provides an alternative cathode material for high‐energy‐density and cost‐effective lithium‐ion batteries. Future possibilities: The cobalt‐free nickel‐rich layered cathode material LiNi0.9Mn0.1O2 with a stable structure and excellent electrochemical performance is synthesized by using a co‐precipitation method. LiNi0.9Mn0.1O2 exhibits a capacity retention of 93 % after 150 cycles at 0.2 C at 2.7–4.3 V and a high thermal decomposition temperature of 234°C. Considering the material contains no cobalt, attaining the present comprehensive performance is attractive.