Mixed silicon-graphite composites were studied as an anode material for LIB. Estimation of the capacity of the composite as a function of silicon mass fraction as well as the lithium mole fraction in the final Li-Si alloy was performed. Based on this estimation, appropriate cycling test was introduced. Possible cycling stability region in terms of Si mass fraction, mole fraction of Li in the Li-Si alloy and average particle size was evaluated. (C) 2004 Published by Elsevier B.V.