Recent progress in electrode materials for aqueous lithium-ion batteries

Aqueous lithium-ion batteries as secondary batteries use aqueous solutions as electrolytes. Such batteries have a great potential for effective use of renewable energy such as wind and solar power because of advantages of low production costs, low toxicity, non-flammability and high ionic conductivity. This paper summarises recent progress in electrode materials (anode and cathode electrodes) for aqueous lithium-ion batteries. Key issues associate with dissolution of electrode materials in electrolytes and side reactions due to active protons in the electrolytes are highlighted and methods of modifying electrode materials are discussed. Future research questions are also outlined.