Electrochemical performance of modified LiMn ₂O ₄ used as cathode material for an aqueous rechargeable lithium battery

To improve the electrochemical performance of cathode material in aqueous LiNO ₃ solution, modified spinel LiMn ₂O ₄ materials prepared with different amounts of sucrose additive are synthesized using a two-step sintering method. The phase structure and morphologies of as-prepared samples are characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. Electrochemical performances of modified LiMn ₂O ₄ used as the cathode material of the aqueous rechargeable lithium battery (ARLB) are investigated by galvanostatic charge/discharge testing. The effects of the carbon, which decomposed from the additive sucrose, on the electrochemical performances of the modified spinel LiMn ₂O ₄ cathode for the ARLBs are discussed. In comparison to pristine LiMn ₂O ₄, the optimum quantity of sucrose addition improves the electrochemical performance of spinel LiMn ₂O ₄ material in an aqueous LiNO ₃ solution, especially for the addition of 20 wt % sucrose, and its initial discharge specific capacity is 118.3 mAh g ^-1; moreover, it still has 102.8 mAh g ^-1 after 40 cycles.