A study of the electrochemistry of lithium aimed to the development of aqueous batteries is presented. The study includes experimental characterization of lithium dissolution in concentrated aqueous KOH solutions. Gathering of the hydrogen evolved at the lithium surface allowed for the delineation of the partial cathodic processes at the anode. The experimental study is complemented with a theoretical model far the interfacial film separating the metal from the electrolyte. The model concludes that the porosity of the film is modified by the inclusion of additives into the KOH electrolyte. Both the hydrogen evolution (partial cathodic processes) and the total current density are impacted by film porosity changes. Cathode characterization is also relevant for the design of a high performance cell. DC and AC studies were performed on nickel and ruthenium cathodes. Special attention was placed on the evaluation of aging properties.