Effect of lithium difluoro(oxalato)borate and heptamethyldisilazane with different concentrations as additives on cycling performance of LiMn2O4 is studied and evaluated at 25°C and 60°C by cyclic voltammetry (CV) test, linear sweep voltage (LSV) test, TG-DSC analysis, conductivity, electrochemical impedance spectroscopy (EIS) and charge–discharge measurements. The results show that the addition of heptamethyldisilazane does not influence the electrochemical performance of LiMn2O4 electrode and the conductivity of original electrolyte basically. What is more, 2vol.% HMDS can apparently improve the cycling performance of LiMn2O4 at room and elevated temperature, while 6vol.% HMDS and 0.2M LiDFOB in the electrolyte have not achieved the desired effect, and even deteriorated the cycling performance of LiMn2O4/Li half cells. When the concentration of the additive is 2vol.%, the battery of LiPF6-based electrolyte with HMDS additive shows perfect cycling performance at room temperature at 2 C rate, and the capacity fading is only 3.8mAh g−1 after 200cycles.