Excellent electrochemical performance of LiNi0.5Co0.2Mn0.3O2 with good crystallinity and submicron primary dispersed particles

Summary Nickel‐cobalt‐manganese ternary cathode materials are known as one of the most promising future cathode materials for Li‐ion batteries (LIBs) due to their high discharge capacity, environmental friendliness, and low cost. In this paper, submicron LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM523) primary particles with good crystallinity and dispersibility have been synthesized combine a coprecipitation method used ethanol as solvent with solid‐phase sintering technology. A feeding strategy through separate dropping of sodium carbonate and ammonia is adopted; the structure and properties of NCM523 under different pH conditions are investigated. It is found that the NCM523 synthesized at pH = 8 (NCM523‐8) exhibits a uniform particle size of about 300 nm, with good crystallinity. The NCM523‐8 exhibits an excellent high‐potential cycling performance, with an initial discharge capacity of 193.6 mAh g −1 at 0.2 C in the voltage of 3.0 to 4.5 V, and the capacity retention is 91% after 100 cycles. It also shows excellent rate performance with a reversible capacity of 130 mAh g −1 at 5 C. The superior high‐potential electrochemical performance is attributed to the improved lithium‐ion diffusion coefficient and stabilized structure by the special structural characteristics as evidenced by cyclic voltammetry, electrochemical impedance spectroscopy, and X‐ray diffraction.