Proton batteries shape the next energy storage

Merited by its fast proton diffusion kinetics, proton batteries are qualified as one of the most next-generation energy storage devices. The recent emergence and explosive development of various proton batteries requires us to re-examine the relationship between protons and electrode materials. Thus, our review focuses on the individual issues and their link from proton transport pathway (electrolytes), interfacial transport (electrolyte/electrode materials) to proton conduction mechanism (electrode materials). Together with addressing the effect of physical and chemical properties of proton and hydrogen bonds (especially symmetric hydrogen bonds), we further summarize the underlying proton conduction mechanisms. The interaction between electrode materials and proton was elucidated. Since the proton battery is still in its infancy, the mechanism-oriented direction and challenges are highlighted with practical applications of proton batteries.