The Korean Society of Surface Science and Engineering

Seawater secondary batteries are gaining attention as a new energy storage system that offers a stable supply of resources, cost savings, and enhanced safety compared to traditional lithium-ion batteries (LIBs). One of the key motivations for considering seawater batteries as an alternative energy storage system is the scarcity and high cost of resources like lithium and cobalt, as well as safety concerns related to the use of organic electrolytes in LIBs. Seawater secondary batteries utilize sodium ions and leverage the abundant and low-cost seawater as the cathode material, which reduces costs and allows for the easy construction of large-scale systems without the need for frequent electrode material replacement. Additionally, the natural cooling effect of seawater facilitates thermal management of the battery system, helping to reduce the overall system size. The reaction mechanisms and components of seawater secondary batteries are discussed. The oxidation-reduction reactions of sodium ions during charge and discharge, as well as the specific reactions occurring at the anode and cathode, are explained. In the main body of this paper, the influence of these reactions on the electrochemical performance of seawater secondary batteries is also examined. In particular, research findings related to carbon-based materials used as anodes, various composites, non-aqueous electrolytes as anolytes, and cathode catalysts are discussed in detail. In conclusion, while seawater secondary batteries hold great potential as an alternative energy storage system, there are still several challenges that need to be addressed before commercialization. Continued research is required to improve battery performance and ensure long-term stability through material advancements, as well as to explore cost reduction strategies for large-scale commercialization.

Keywords Sewater, Battery, Rechargeble