Electrochemical study on LiCo 1/6Mn 11/6O 4 as cathode material for lithium ion batteries at elevated temperature
A novel process via sintering of a precursor from the solution of metal acetates by spray-drying technology was used to synthesize Co-substituted LiCo 1/6Mn 11/6O 4 material for lithium ion batteries. The as-prepared particles were identified as single-phase spinel structure without any impurities in the XRD pattern. The SEM image showed that the particles had good cubic shapes and uniform size distribution with sizes of about 100-200 nm. An ex situ XRD technique was used to characterize the first charge process of the LiCo 1/6Mn 11/6O 4 electrode. The result suggested that the material configuration maintained invariability. The electrochemical properties of the synthesized cathode material were investigated using Li-ion model cells at room and elevated temperature, respectively. In the charge/discharge potential of 3.5-4.4 V at 1/10 C rate, the LiCo 1/6Mn 11/6O 4 electrode delivered high initial capacities of 123 and 127 mAh g -1 at 25 and 55 °C, respectively. Electrochemical cycling tests revealed that the capacity fading occurred mainly in the high-voltage region of 4.08-4.40 V, and the fading rate was 0.107% and 0.302% per cycle at 25 and 55 °C, respectively. The excellent cycling stability and low material cost make it an attractive cathode for high-temperature lithium ion batteries.