"Synthesis and Electrochemical Performance of a Lithium Titanium Phosphate Anode for Aqueous Lithium-Ion Batteries"

Colin Wessells: Fabio La Mantia, Heather Deshazer, Robert A. Huggins, and Yi Cui; Journal of the Electrochemical Society , 1/25/11.

Additional Authors: Fabio La Mantia, Heather Deshazer, Robert A. Huggins, and Yi Cui

Abstract:

Lithium-ion batteries that use aqueous electrolytes offer safety and cost advantages when compared to today’s commercial cells that use organic electrolytes. The equilibrium reaction potential of lithium titanium phosphate is−0.5Vwith respect to the standard hydrogen electrode, which makes this material attractive for use as a negative electrode in aqueous electrolytes. This material was synthesized using a Pechini type method. Galvanostatic cycling of the resulting lithium titanium phosphate showed an initial discharge capacity of115mAh/gand quite good capacity retention during cycling, 84% after100cycles, and 70% after160cyclesat a1Ccycling rate in an organic electrolyte. An initial discharge capacity of113mAh/gand capacity retention of 89% after100cycleswith a coulombic efficiency above 98% was observed at a C/5 rate inpH-neutral2MLi2SO4. The good cycle life and high efficiency in an aqueous electrolyte demonstrate that lithium titanium phosphate is an excellent candidate negative electrode material for use in aqueous lithium-ion batteries.