An electrode composition for a lithium-ion battery comprising particles
having an average particle size ranging from 1 .mu.m to 50 .mu.m. The
particles include an electrochemically active phase and an
electrochemically inactive phase that share a common phase boundary. The
electrochemically active phase includes elemental silicon and the
electrochemically inactive phase includes at least two metal elements in
the form of an intermetallic compound, a solid solution, or combination
thereof. Each of the phases is free of crystallites that are greater than
1000 angstroms prior to cycling. In addition, the electrochemically
active phase is amorphous after the electrode has been cycled through one
full charge-discharge cycle in a lithium-ion battery.