High-energy lithium-rich and manganese-based layered materials are one of the most promising candidates for the cathode materials of lithium-ion batteries. These cathode materials can deliver anomalously high capacity due to multiple electron transfers involving both cationic and anionic redox processes. An unprecedented homogeneous monoclinic Li2MnO3-like structured material Li1.2Ni0.25Mn0.55O2, which with the highest nickel content among the Li-rich materials, is first disclosed in this work. Our proposed Li1.2Ni0.25Mn0.55O2 material can deliver a reversible capacity exceeding 295 mAh·g−1 with a high and stable discharge voltage. It is especially encouraging that the as-prepared Li1.2Ni0.25Mn0.55O2 cathode material displays high charge-discharge efficiency and good capacity retention during cycling. In this work, we applied in-situ EIS and ex-situ XPS methods to systematically investigate the reversible structural evolution of Li1.2Ni0.25Mn0.55O2 cathode material and cathode-electrolyte interfaces (CEI). These findings will shed light on the design of high-performance cathode materials for lithium-ion batteries.
- Anionic redox
- Cathode-electrolyte interfaces
- Lithium-ion batteries
- Lithium-rich cathode materials
- Reversible structural variation