Surface modification of Li rich Li1.2Mn0.54Ni0.13Co0.13O2 cathode particles

Abstract Li-rich Mn-based layered oxide Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 (LMNCO) has received great interest due to its high discharge capacity. However, the fast capacity attenuation seriously hinders its wide application. LMNCO particles are synthesized via a co-precipitation method. To enhance the cycle stability, (Ni 0.4 Co 0.2 Mn 0.4 ) 1-x Ti x (OH) 2+2x surface layer is deposited on LMNCO precursor particles by a second co-precipitation process. Due to the mutual diffusion of elements during sintering, Ti is distributed in the 2–3 μm shell of particles. The cells are cycled in a voltage window of 2.0–4.8 V at 0.5C. After 200 cycles, LMNCO exhibits a capacity retention of 43%, and LMNCO particles have been pulverized by the cycle process. In contrast, the structural integrity of coated particles is maintained, and therefore the cycle stability is evidently improved.