Rechargeable Seawater Batteries—From Concept to Applications

Abstract

Harvesting energy from natural resources is of significant interest because of their abundance and sustainability. Seawater is the most abundant natural resource on earth, covering two‐thirds of the surface. The rechargeable seawater battery is a new energy storage platform that enables interconversion of electrical energy and chemical energy by tapping into seawater as an infinite medium. Here, an overview of the research and development activities of seawater batteries toward practical applications is presented. Seawater batteries consist of anode and cathode compartments that are separated by a Na‐ion conducting membrane, which allows only Na+ ion transport between the two electrodes. The roles and drawbacks of the three key components, as well as the development concept and operation principles of the batteries on the basis of previous reports are covered. Moreover, the prototype manufacturing lines for mass production and automation, and potential applications, particularly in marine environments are introduced. Highlighting the importance of engineering the cell components, as well as optimizing the system level for a particular application and thereby successful market entry, the key issues to be resolved are discussed, so that the seawater battery can emerge as a promising alternative to existing rechargeable batteries.

In Situ Replenishment of Formation Cycle Lithium‐Ion Loss for Enhancing Battery Life

“…Development on an extended battery lifetime system is of practical importance but faces tough challenges using a conventional cell configuration with a typical charge-discharge cycling process. However, the remarkable studies on electrolyte refilling, [54] electrode pretreatment [55,56] and replacement with fresh electrodes [57] have been found to extend the lifetime of a rechargeable battery and have showcased a significant improvement in the capacity and cycle life performance. However, these additional processing steps are time-consuming, economically unfeasible require special handling and the uncertainty of the…”

A review on recent approaches for designing the SEI layer on sodium metal anodes

“…The upcoming unstable lithium market has motivated researchers to find alternative secondary ion batteries such as sodium-ion batteries (SIBs), which have electrochemical features similar to those of LIBs. 25,26 Generally, sodium can be extracted easily through the electrolytic reduction of sodium chloride, which is naturally abundant in seawater; 27 thus, it is unlikely to be affected by limited supply and price fluctuations. In addition, the copper current collector could be replaced with the lighter and cheaper aluminum as sodium does not react with aluminum at a low potential.…”

Design of Large‐Scale Rectangular Cells for Rechargeable Seawater Batteries

“…[ 5 ] Nevertheless, despite the economic advantage of production process, the large‐scale production of these metal‐based batteries have been limited by their lower gravimetric and volumetric energy densities. [ 6 ] In addition, these classes of batteries, further suffer from heat generation during charge or discharge process which gradually reduce the performance of the battery. [ 7 ] The so‐called seawater batteries have been newly conceived to utilize seawater as the abundant source of sodium as the active material.…”