Electrochemical insertion of lithium into graphite-zinc composites

摘要

Metal-based composites are currently under investigation as possible negative-electrode materials in lithium-ion batteries. We present here a new composite material composed of zinc particles deposited mainly onto graphite surfaces. This Zn/graphite composite was prepared by reduction of zinc chloride ZnCl2 by a KC8 graphite intercalation compound in tetrahydrofuran. Electrochemical insertion of lithium occurs both in graphite and in zinc. A stable specific charge of 355 mAh g(-1) is obtained starting from the third charge/discharge cycle. As in Sb/graphite composites prepared by the same technique, the stabilizing role of graphite against metal fragmentation and pulverization is demonstrated.