New amorphous thin-film lithium electrolyte and rechargeable microbattery

Abstract
Sputtering of Li 3 PO 4 in pure N 2 results in the formation of an amorphous lithium electrolyte that is suitable in contact with lithium and has electrical properties that are suitable for application in a thin-film cell. Thin-film rechargeable lithium cells have been fabricated and characterized using this electrolyte between a lithium anode and an amorphous vanadium oxide cathode. The open circuit voltage of the cell is 3.6 to 3.7 V, and it has a capacity of 130 μAh/cm 2 when discharged to 1.5 V. The AC impedance of the cells measured at different stages of discharge indicate a significant decrease in internal resistance at about the midpoint of the discharge Author(s) Bates, J.B. Oak Ridge Nat. Lab., TN, USA Gruzalski, G.R. ; Dudney, N.J. ; Luck, C.F.