Controlled synthesis of lithium-rich layered Li_(1.2)Mn_(0.56)Ni_(0.12)Co_(0.12)O_2 oxide with tunable morphology and structure as cathode material for lithium-ion batteries by solvo/hydrothermal methods

摘要

A Li-rich layered cathode material Li_(1.2)Mn_(0.56)Ni_(0.12)Co_(0.12)O_2 (0.5Li_2MnO_3-0.5Li_(1.2)Mn_(0.4)Ni_(0.3)Co_(0.3)O_2) with different morphologies has been successfully prepared by solvothermal and hydrpthermal methods. The result demonstrates that the solvent plays a crucial role in the formation of the precursor and final product with various shapes and sizes. When tested as the cathode material for lithium ion batteries, the sample prepared by solvothermal method exhibits higher discharge capacity, better cycling performance, and more excellent rate capacity. It delivers a discharge capacity of 306.9 mAhg~(-1) at 0.2 C and 118.6 mAhg~(-1) even at a high rate of 5.0 C. The outstanding performance of the sample prepared by solvothermal method can be attributed to the well-ordered structure and well-defined morphology with smaller particle size and uniform distribution. The current study paves a new concept and applicable way to prepare high performance Li-rich layered cathode material for LIBs.