Cycling and storage performance at elevated temperatures of LiNi0.5Mn1.5O4 positive electrodes for advanced 5 VLi-ion batteries

The electrochemical behavior of substituted spinel-nickel electrodes, LiNi0.5Mn1.5O4, was studied during prolonged cycling (Li-ion extraction/insertion) and storage at elevated temperatures. We have found that using an appropriate cycling protocol (constant current/constant voltage) of Li/LiNi0.5Mn1.5O4 cells, high charge-discharge capacities of the positive electrodes, around 140 mAh/g, can be obtained. At elevated temperatures, spinel-nickel electrodes demonstrated a stable performance and sufficient capacity retention in electrolyte solutions comprising alkyl carbonates (EC, DMC) and LiPF6. (C) 2004 Elsevier B.V. All rights reserved.