Si-O polymeric network derived from sol-gel transformation of methyltrimethoxysilane (MTMS) was formed on powdered silicongraphite mixture. The resultant composite was used as negative electrode materials in lithium-ion test cells. Effect of catalyst used (HCl and NH_4OH) during sol-gel transformation on the final electrochemical performance of the negative electrode materials was studied. Materials prepared using NH_4OH as catalyst showed better cycleability than those prepared using HCl as catalyst. Initial specific capacity of the composites prepared was around 450 mAh/g, which was lower than that of a mechanical mixture of graphite and silicon of similar content (～900 mAh/g) but higher than that of graphite (～300 mAh/g). SEM studies revealed that composite particles consist of agglomeration of smaller parts and their average size was about 20 μm. Powder x-ray diffraction showed that the polymeric network formed was amorphous.
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