Cycle Performance Improvement of LiMn2O4 Cathode for Lithium Ion Battery by "Nano Inclusion" Formation

(1-x)LiMn2O4-xZn2SnO4(x = 0, 0.02, 0.05, 0.1) were fabricated and the cycle performance of the samples was measured. For x > 0, transmission electron microscopy measurement revealed that the nano-scale crystals, which we named "Nano Inclusions", with spinel structure are formed within LiMn2O4 single crystals, and that LiMn2O4 and "Nano Inclusion" connect without grain boundary. The discharge capacity retention rate increased with the increase of x. It is considered that "Nano Inclusion" blocked crack propagation caused by volume change during charge and discharge cycles and prevented dead region formation which led to capacity fading.