The electrochemical properties of the Li-ion battery with a lithium manganese oxide (LiMn2O4) cathode are improved by efficiently reducing the reaction between LiMn2O4 and hydrofluoric acid (HF) produced in the electrolyte. By introducing fine ZrO2 particles in the slurry during fabrication, Mn dissolution of the cathode during the charge–discharge cycles is minimized by scavenging the HF produced in the cell. Results from galvanostatic experiments show that the capacity retention of the LiMn2O4 fabricated with new method is maintained up to 92% after 50 cycles at room temperature and 76% at high temperature without losing initial capacity. The improvement in the electrochemical properties of the cathode prepared by this method is superior to other approaches in terms of fabrication process and it sheds light on the possibility of further improving the electrochemical properties of LiMn2O4.