Electrochemical Properties of Oxysulfide LiAl0.24Mn1.76O3.98S0.02

초록

A new sulfur-doped spinel material, LiAl0.24Mn1.76O3.98S0.02 with a sub-micron and well-developed octahedral structure was synthesized by a sol-gel method using glycolic acid as a chelating agent. The structural integrity of the oxysulfide material before and after the charge-discharge cycling was measured by XRD and HRTEM. Our as-synthesized material overcomes the Jahn-Teller distortion in all operating voltage regions. It exhibits capacities of 103, 128, and 230 mAh/g in the 4 V (4.4-3.0 V), 3 V (2.4-3.5 V), and both the 3 and 4 V regions (4.4-2.4 V), respectively, with excellent cyclability.