Recently, all solid lithium batteries have been studied for a solution of safety problem in EV and ESS applications. The batteries are composed of cathode, solid electrolyte and lithium metal as anode. In here, lithium dendrite and dead lithium were formed on the surface of lithium electrode during charge and discharge cycling, resulting in the rapid degradation of battery capacity.

In order to improve the above problems in all solid lithium batteries, interface layer, which is made of graphite-based thin composite film, was introduced between solid electrolyte and lithium metal. The interface layer showed a great improvement of cycling performance of all solid lithium battery. Furthermore, it was possible to reduce the thickness of lithium metal due to the reduction of lithium consumption during the charge and discharge cycling.