Dependence of electrochemical properties of spinel LiMn2O4 on Li2CO3 with micro-flaky, micro-flower and nanorod morphologies

Abstract

Herein, the dependence of spinel LiMn2O4 on Li2CO3 with micro-flaky, micro-flower and nanorod morphologies is investigated. The results show that the as-synthesized LiMn2O4 with micron sized Li2CO3 as raw materials have a much higher discharge capacity than that of the one prepared with nano sized Li2CO3. It delivers an initial charge capacity of 110.1, 105.2 and 104.9 mA h g-1 followed by a discharge capacity of 109.1, 103.9 and 104.2 mA h g-1 with the micro-flower, nanorod and micro-flaky Li2CO3 morphologies, respectively, at room temperature (about 99% of the charge capacity is discharged). The smaller specific surface area is found in the spinel LiMn2O4 with micron sized Li2CO3, resulting in a better stable electrochemical performance in LiMn2O4 with micro-flower and micro-flaky Li2CO3. Their capacities are maintained at 99.2 mA h g-1 and 94.2 mA h g-1 after 100 cycles at 1C rate. The capacity retention was more than 90% at the 100th cycle with the micron-sized Li2CO3. Moreover, the as-synthesized spinel LiMn2O4 with micro-flower Li2CO3 retained more than 95% of its initial discharge capacity (92 mA h g-1) after 200 cycles at 2C rate. The cubic spinel structure was detected after 200 cycles of LiMn2O4 at 2C rate.