▎ 摘 要
NOVELTY - Method for producing graphene-silicon composite complex, involves (a) preparing an aqueous dispersion of graphene oxide by dispersing graphene oxide in water, (b) adding tetraethyl orthosilicate and a metal reducing agent comprising magnesium, aluminum, titanium or calcium to the aqueous dispersion to obtain a mixed liquid, (c) drying the mixed liquid to obtain a mixture containing graphene oxide, silica and metal reducing agent, and (d) carrying out heat reduction of the mixture to obtain the product. USE - The method is useful for producing graphene-silicon composite complex for a negative electrode active material of a lithium ion battery. ADVANTAGE - The composite complex is prepared by simple method and easy to secure conductive path for electrons, has excellent conductivity, dispersibility and handling effect, maintains electrical contact between silicon and graphene, improves cycle characteristics when charging and discharging are repeated, suppresses expansion and shrinkage of the negative electrode during charge and discharge when an aggregate is contained, suppresses collapse of the negative electrode, reduces volume, and improves degree of freedom in shape, and degree of improvement in conductivity and electrode capacity.