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

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 with 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 of and quite good capacity retention during cycling, 84% after , and 70% after at a cycling rate in an organic electrolyte. An initial discharge capacity of and capacity retention of 89% after with a coulombic efficiency above 98% was observed at a C/5 rate in -neutral . 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.