Electrochemistry and structure of Li-rich cathode composites: Li1.26Fe0.22Mn0.52O2in situ integrated with conductive network-graphene oxide for lithium-ion batteries

Abstract

A novel designed graphene oxide integrated Li-rich cathode material Li_1.26Fe_0.22Mn_0.52O₂ (GO-LFMO) is obtained by integrating nanosized Li_1.26Fe_0.22Mn_0.52O₂ (LFMO) materials with different amounts of graphene oxide (GO) through an in situ method. The graphene oxide is designed as the carbon conductive network to regulate and control the micro/nano structure of the composites. Scanning electron microscopy (SEM) reveals that the plate shape composite consists of nano particles with uniform particle size. The elemental mapping results prove that the carbon conductive framework is formed uniformly in the composites. The rate performances of the GO integrated samples are highly improved compared with the pristine one due to the superior conductivity of the conductive networks. Electrochemical Impedance Spectroscopy (EIS) results demonstrate that the graphene oxide conductive networks can remarkably decrease the cell resistance especially the charge transfer resistance.