Influence of Doping Rare Earth on Performance of Lithium Manganese Oxide Spinels as Cathode Materials for Lithium-Ion Batteries

摘要

Some rare earth doping spinel LiMn_(2-x)RE_xO_4(RE = La, Ce, Nd) cathode materials for lithium ion batteries were synthesized by the solid-state reaction method . The structure characteristics of these produced samples were investigated by XRD, SEM , and particle size distribution analysis . According to the microstructure and charge-discharge testing , the effect of doping rare earth on stabilizing the spinel structure was analyzed . Through a series of doping experiments , it is shown that when the doping content x within the range of 0.01 approx 0.02 the cycle performance of the materials is greatly improved. The discharge capacity of the sample LiMn_(1.98)La_(0.02)O_4, LiMn_(1.98)Ce_(0.02)O_4 and LiMn_(1.98)Nd_(0.02)O_4 remain 119.1, 114.2 and 117.5 mAh cebter dot g~(-1) after 50 cycles.