Electrochemical Behavior of the Amorphous Tin-Cobalt Anode

The electrochemical behavior of the amorphous tin anode was found to be much superior to that of crystalline tin based materials. At all depths of cycling, from 10% to 40%, the amorphous anode showed no loss of capacity in contrast to crystalline tin foil. Lithium removal was found to be very fast with little loss of capacity up to at least 15 mA/cm(2) ( = 6 C); however, lithium insertion appears to be rate limited. An ex situ X-ray analysis revealed that annealing triggers the crystallization and grain size growth in the amorphous tin, resulting in a rapid fall-off in capacity. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3496398] All rights reserved.