What If Electrochemical Energy Systems Were Made 40% More Efficient?

Abstract

Electrochemical systems related to energy storage and generation have inherent thermodynamic advantages over thermal energy systems because electrochemical systems have do not require moving parts. Thermodynamic Carnot limitations restrict internal combustion engines (ICEs) to about 40% theoretical energy conversion efficiencies. Thermodynamically, electrochemical energy systems can be 100 % efficient. The high thermodynamic efficiency is however challenged by dynamics of kinetics and transport. Because electrochemical energy systems generally operate at lower temperatures and pressures than ICEs, greater finesse in design of catalysis is needed.Electrochemical energy systems made 40% more efficient would substantially advance the economic and environmental advantages of electrochemical electrochemical energy. Consider mechanisms of physical catalysis where a physical gradient rather than a chemical composition drives chemical change. Magnetoelectrocatalysis is an example of physical catalysis that may provide means to enhance the efficiency of electrochemical energy systems.Magnetoelectrocatalysis exploits magnetic gradients imposed at electrode surfaces to facilitate electron transfer and so electrocatalysis.Here, magnetoelectrocatalysis is shown to increase energy, power, and conversion efficiency of several electrochemical energy systems by 40%. Examples include: Proton exchange membrane (PEM) fuel cellsAlkaline batteries (MnO2|Zn)Hydrogen evolution reaction (HER) at glassy carbonMnO2 supercapacitors Magnetic gradient effects on electrochemical efficiency are also observed for several environmentally relevant electrode reactions. CO oxidation on PtHER on various metal electrodes and photocathodesC1 reactions at rare earth electrocatalysts From these outcomes, it is suggested that magnetoelectrochemical catalysis may provide a path to substantially more efficient electrochemical energy systems, perhaps approaching 40%.Work is undertaken at the University of Iowa. The National Science Foundation (NSF CHE-1309366 and NSF CHE-0809745) and the Army Research Office (W911NF-19-1-0208 (74912-CH-II)) supported these projects.