Articles and methods involving protected electrode structures are generally provided. In some embodiments, a protected electrode structure includes an electrode comprising an alkali metal and a protective structure directly adjacent the electrode. In some embodiments, the protective structure comprises elemental carbon and intercalated ions. In some embodiments, the protective structure is a composite protective structure. The composite structure may comprise an alloy comprising an alkali metal, an oxide of an alkali metal, and/or a fluoride salt of an alkali metal.