Highly improved voltage efficiency of seawater battery by use of chloride ion capturing electrode > Publication | UNIST YK RESEARCH

Publication

Publication

Highly improved voltage efficiency of seawater battery by use of chloride ion capturing electrode
Author
Kyoungho Kim, Soo Min Hwang, Jeong-Sun Park, Jinhyup Han, Junsoo Kim, Youngsik Kim
Journal
Journal of Power Sources
Vol
313
Page
46-50
Year
2016
Cost-effective and eco-friendly battery system with high energy density is highly desirable. Herein, we report a seawater battery with a high voltage efficiency, in which a chloride ion-capturing electrode (CICE) consisting of Ag foil is utilized as the cathode. The use of Ag as the cathode leads to a sharp decrease in the voltage gaps between charge and discharge curves, based on reversible redox reaction of Ag/AgCl (at ∼2.9 V vs. Na+/Na) in a seawater catholyte during cycling. The Ag/AgCl reaction proves to be highly reversible during battery cycling. The battery employing the Ag electrode shows excellent cycling performance with a high Coulombic efficiency (98.6–98.7%) and a highly improved voltage efficiency (90.3% compared to 73% for carbonaceous cathode) during 20 cycles (total 500 h). These findings demonstrate that seawater batteries using a CICE could be used as next-generation batteries for large-scale stationary energy storage plants.