Ion-Exchange Desalination Battery with Reversible Chloride Capture

Abstract

Seawater desalination technology aims to address the global water shortage resulting from climate change. However, for a viable solution, it is imperative to utilize renewable energy sources without carbon emissions. Desalination batteries represent a promising water-energy nexus technology; nonetheless, the limited reversibility of Cl- capture hinders their practicality. In this study, an ion-exchange desalination battery (IEDB), composed of an anion-exchange resin (AER) column filled with IRA-67 and a seawater battery (SWB), concurrently stores energy and desalinates seawater. During the charging of the SWB, Cl- is adsorbed on IRA-67, leading to seawater desalination. Subsequently, the Cl- is desorbed during discharge, automatically regenerating IRA-67 through the chemical potential. The proposed IEDB demonstrates 358 mL of seawater desalination with 1.48 Wh of energy storage through repetitive charge-discharge. This result secures the stability of desalination batteries, which is essential for an efficient water-energy nexus.