Attaining a long cycle life of Li charge/discharge for less graphitized carbon by forming a C/C composite

For the purpose of improving the Li charge/discharge cycle performance of l ess graphitezed carbon for the anode of Li-ion secondary batteries, the act ive material was made into C/C composite. A carbon fiber felt prepared at l ower temperatures were impregnated with epoxy resin and pyrolyzed at a desi red temperature. The SEM picture of the C/C composite thus obtained showed that each individual fiber was bound together by the carbon formed by pyrol ysis. The charge/discharge cycle test was performed in propylene carbonate containing 1 M (M = mol dm(-3)) LiCIO4. It was found that the cycleability was improved remarkably for the C/C composite.