image: Schematic illustration of aqueous metal ion batteries (AMIBs) and the corresponding ion mass transfer and electrode reaction along the clue of the ionic pathway from anode and electrolyte to interface and cathode. The words with red color present the chemistry and electrochemistry challenges at each part of AMIBs.
Credit: ©Science China Press
Aqueous metal ion batteries (AMIBs) with intrinsic safety are widely accepted as one promising solution for advanced energy storage. Despite the laboratory-scale progress in battery components and mechanisms featured by large specific capacities and long lifespans, AMIBs' practical use meets challenges with electrodes and electrolytes.
This review by Prof Jieshan Qiu and Prof Qi Yang of Beijing University of Chemical Technology, and Prof Chunyi Zhi of City University of Hong Kong, has provided new insights into the challenges faced by AMIBs from perspectives of electrode reaction and ion mass transfer, in particular the dramatic degradation of battery performance during the electrode/battery scaleup. It is shown that the effects of electrode materials and aqueous electrolyte chemistry in practical applications are the key issues leading to the battery performance degradation at thick electrodes with high loading mass. In this review, the ion mass transfer in electrolytes, across electrolyte-cathode interface, and in cathodes (featured by lattice-void and particle-gap ion mass transfer) are discussed. The cathodic electrode reactions are analyzed in terms of accelerated kinetics and suppression of active specie loss based on catalysis chemistry and micro-reactor construction. Finally, the authors have provided a developmental perspective on the challenges and future directions for the lab-to-market transition of AMIBs.