The Role and Influence of NCM622 Cathode Material in Lithium-Ion Batteries

Under the impetus of global energy transition and the "dual carbon" goals, the demand for lithium-ion batteries has surged. Cathode materials are the core determinant of their performance. Among nickel-cobalt-manganese oxide (NCM) ternary materials, NCM622 (with a Ni: Co: Mn ratio of 6: 2: 2) is widely applied due to its balanced advantages in energy density and safety. However, NCM622 faces challenges such as insufficient high-rate charge-discharge performance, long-term cycle capacity decay, and cost constraints of cobalt resources, which restrict its further application. Additionally, its performance stability under extreme temperature conditions (both high and low temperatures) is unsatisfactory, with capacity fading accelerating sharply in high-temperature environments and ion diffusion kinetics deteriorating noticeably in low-temperature conditions, further impairing its practical application value. This paper focuses on the impact mechanism of NCM622 on the performance of lithium-ion batteries, analyzes the correlation between its crystal structure, chemical composition and the energy density and safety of batteries, explores the ion diffusion kinetics and structural evolution laws, and elaborates on the performance optimization strategies and application prospects.