Obtaining P2‐Na 0.56 [Ni 0.1 Co 0.1 Mn 0.8 ]O 2 Cathode Materials for Sodium‐Ion Batteries by using a Co‐precipitation Method

For the sake of achieving the practical application of sodium‐ion batteries, extensive efforts have been made to improve the electrochemical performance of cathode materials. A simple co‐precipitation route is successfully developed to synthesize nanowires of transition metal hydroxides through a sodium peroxide pouring process instead of the traditional sodium hydroxide dropping approach. After a subsequent annealing process, a well‐crystallized P2‐Na 0.56 [Ni 0.1 Co 0.1 Mn 0.8 ]O 2 layered cathode material is obtained. Owing to such an exquisite architecture, this material possesses an excellent electrochemical performance, exhibits a reversible capacity of 188 mAh g −1 at 48 mA g −1 in the voltage range of 1.5‐4.1 V with nearly 99.7 % coulombic efficiency and retains approximately 80.2 % of the initial capacity after 50 cycles. Moreover, even at an extremely high current density of 2400 mA g −1 , it delivers a capacity of 134 mAh g −1 and remains at 76 mAh g −1 after 1500 cycles, which surpasses most reported layered transition metal oxide cathode materials. This strategy of providing a strong oxidizing environment during the co‐precipitation process is especially crucial for obtaining materials with excellent electrochemical performances for future energy storage application.