The Synthesis and Electrochemical Property of Spinel Cathode Material Li-1.05[(Mn(1.9)9Gd(0.01))(0.91)(Mn1.8Co0.2)(0.09)]O-4 for Lithium Ion Batteries

摘要

Novel spinel Li-1.05[(Mn1.99Gd0.01)(0.91)(Mn1.8Co0.2)(0.09)]O-4 as cathode material for Li -ion battery was prepared through two-step solid-state reaction and treatment by Li-Mn-Co-O material on the surface of Li-1.05[Mn1.99Gd0.01]O-4 particles. The physical and electrochemical properties of the materials were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV) and charge-discharge test. The novel material showed improved electrochemical properties compared with the pristine LiMn2O4, especially at elevated temperature. The initial discharge capacity of the Li-1.05[(Mn1.99Gd0.01)(0.91)(Mn1.8Co0.2)(0.09)]O-4 was 128.0 mAh g(-1) with a fading rate of 0.041% per cycle at 25 degrees C. Moreover, the cycle ability was improved more evidently at 55 degrees C, the retentions ratio of capacity was up to 91% for the novel material after 100 cycles.