Optimization of lithium titanate electrodes for high-power cells

A full-cell mathematical model is used to compare the performance of graphite (LixC6) and lithium titanate (Li4+3xTi5O12) negative electrodes, with a doped lithium manganese oxide (Liy+0.16Mn1.84O4) positive electrode. The cell designs are optimized over electrode thickness and porosity, and several particle sizes are examined for the lithium titanate/manganese oxide system. Although the graphite-based cell contains a higher specific energy than the titanate-based cell, the latter performs better at high rates (> 12C) when submicrometer particle sizes are used for both the positive and negative electrode. In light of this and several life-related advantages possessed by the Li4+3xTi5O12 electrode, it is recommended for development as a high-power energy storage system. (c) 2006 The Electrochemical Society.