Improved electrochemical performances of oxygen plasma treated LiMn 2O4 thin films
Journal
Physica Scripta T
Journal Volume
T129
Pages
74-79
Date Issued
2007
Author(s)
Abstract
LiMn2O4 spinel thin films were deposited by radio frequency (rf) magnetron sputtering followed by annealing at 600 °C in air.The films were then post-treated with an rf driven oxygen plasma. The crystallization and surface morphology of LiMn2O4 thin films were seen to change with rf power. The treated samples were tested under harsh conditions such as deep discharge to 1.5 V and cycling at elevated temperature of 60 °C to verify the electrochemical performances of LiMn 2O4 cathodes. The oxygen plasma treatments improved the electrochemical properties of LiMn2O4 thin films significantly. As the cells were cycled in the range of 4.5-2.0 V at 60 °C, the samples treated at a proper rf power of 50 W exhibited an initial capacity greater than ∼400 mAh g-1 with reasonable cycling stability. The results were attributed to the change of morphology and the formation of a surface layer induced by the oxygen plasma irradiation. © 2007 The Royal Swedish Academy of Sciences.
Type
conference paper