From bulk to thin-film electrolytes in all-solid-state batteries: challenges and opportunities

Currently, transition to all-solid-state batteries from common lithium-ion batteries containing liquid electrolytes is relevant due to the risk of self-ignition and even explosion of the latter devices. Furthermore, for solid electrolytes, lithium metal, which has record high specific capacity compared to currently used carbon materials, can serve as the anode. This review analyzes for the first time the possibilities of transition to thin-film solid electrolytes in lithium power sources. The review addresses the set of problems related to material synthesis, technological principles of the formation of electrolyte samples of various thicknesses, and conductivity of electrolyte films that can be achieved. The set of data concerning the relationship between the electrolyte conductivity and film thickness is considered; the problem of specific conductivity decrease upon a decrease in the thickness of the electrolyte film is addressed. The implemented approaches to solving the problems of material degradation in the electrode–electrolyte interfacial region are systematized. <br> The bibliography includes 282 references.