Electrochemical investigations of lithium-aluminum alloy anode in Li/polymer cells

A first study demonstrating the electrochemical cyclability of the LiAl all oy anode in the Li/polymer cells reported was carried out using LiAl/PEO30- LiN(CF3SO2)(2)/V2O5 cells in which the cell capacities were limited by LiAl anode. The cells fabricated with LiAl anode exhibited excellent electroche mical performance. The coulombic efficiency throughout the cell cycling was also close to 100% indicating that the lithium dendrite formation in LiAl/ PEO30-LiN(CF3SO2)(2)/V2O5 cells is significantly reduced. The reduction in the lithium dendrite formation was attributed to lower lithium activity in the LiAl alloy and its higher open-circuit voltage (370 mV versus Li). The cell voltage was, however, somewhat lower due to the higher open-circuit vo ltage of LiAl anode. The use of the LiAl alloy allows us to operate the cel l at higher temperatures. Higher operating temperature improves the reactio n kinetics while reducing the polarization losses associated with ohmic, ma ss transport, and diffusion. (C) 2001 Elsevier Science B.V. All rights rese rved.