It is important to remark that the reduction of the energy barriers is not a consequence of the emerging metallic states as it has been claimed in the literature. We confirm that the poor electronic conductivity of lithium peroxide even at its surfaces is one of the main limitations for the operation of the LOBs. The effect of Na-doping induces structural distortions by promoting lithium vacancies and will also improve the electronic conductivity mediated by polarons as suggested in Refs. In this line, our results suggest that K-doping will be even more effective in reducing the overpotential since more lithium vacancies and more structural distortions are expected for this heavier heteroatom.