Electrodes comprising an alkali metal, for example, lithium, alloyed with nanostructured materials of formula Si.sub.zGe.sub.(z-1), where 0<z.ltoreq.1; formula Si.sub.zGe.sub.(z-1), where 0<z<1; and/or germanium exhibit a combination of improved capacities, cycle lives, and/or cycling rates compared with similar electrodes made from graphite. These electrodes are useful as anodes for secondary electrochemical cells, for example, batteries and electrochemical supercapacitors.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Some aspects of this disclosure were made with the support of the Department of Energy of the U.S. Government through Basic Energy Sciences Grant No. DE-FG03-00ER15035. The U.S. Government may have certain rights in the invention.