Li‐insertion into sol‐gel Na 0.44 MnO 2 cathode material for higher structure and electrochemical performance of batteries

Stability of electrolyte with higher electrochemical and structural performance is a key aspect for achieving greater longevity of cycle life of battery. In this article, we investigated the electrochemical performance of sol‐gel Na 0.44 MnO 2 (SG‐NMO) as cathode material in lithium batteries within nonaqueous lithium electrolyte. The SG‐NMO was prepared by the two‐step of the sol‐gel method: a transparent gel was obtained by a stirring of precursors (Na 2 CO 3 , Mn(CH 3 COOH) 2 and acid citric) at 80 ° C; then gel was calcinated at 400 ° C for 6 hours and 800 ° C for 9 hours in air. The structure and morphology were characterized by X‐ray diffraction, SEM, and Raman spectroscopy. The XRD pattern exhibited a high crystallization of orthorhombic phase and SEM images showed the well‐crystalline grains in submicrometric scale. Following charge‐discharge profile and ex‐situ XRDs result, SG‐NMO showed 0.22 ion Na + ‐extraction at the end of first cycle and a reversible Li‐migration from second cycle without a phase transition. The specific capacity at rate C/10 was about 180 mAh/g with a capacity retention of 95% upon 50 cycles. Moreover, a good electrochemical performance in rate capability (from C to 3C) indicated a highly kinetic Li‐transportation.