Electric vehicles are mainly powered by lithium-ion batteries, which limit the range of the vehicle. Significant attention is being devoted to alternative, high-energy storage systems such as non-aqueous lithium-oxygen batteries. The Li/O2 battery, however, suffers from issues that limit the reversibility of the electrochemical process and the practical energy density. Therefore, new cell components are needed to improve this system and use it at a practical level.
Jusef Hassoun, University of Ferrara, Italy, Stefano Passerini, Helmholtz Institute, Ulm, and Karlsruhe Institute of Technology (KIT), both Germany, and colleagues have investigated the electrochemical behavior of Li/O2 cells using ionic liquid electrolytes and novel electrode materials. A very promising lithium-metal-free configuration was formed by coupling a LixSn-C alloy anode and a self-standing cathode in an ionic liquid.
The cathode is based on high-surface-area conductive carbon as the reaction host, and polytetrafluoroethylene (PTFE) as the binding agent to enhance the oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) reversibility. The ionic liquid is a mixture of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt and N,N-diethyl-N-(2-methoxyethyl)-N-methylammonium bis(trifluoromethanesulfonyl)imide (DEMETFSI).
The prepared electrode/electrolyte couples show a high reversibility of the redox process. In addition, energy efficiency up to 88 % was obtained, making this system attractive for application.
Article Views: 2201
Please note that to comment on an article you must be registered and logged in.
Registration is for free, you may already be registered to receive, e.g., the newsletter. When you register on this website, please ensure you view our terms and conditions. All comments are subject to moderation.