Electric double layer unlocks molecular switch behind battery

Korean researchers have made a significant discovery regarding how molecular structures change in a tiny space known as the "electric double layer. " This research, published in Nature Communications, can improve battery, hydrogen, and carbon-neutral technologies by reducing energy loss and enabling better reactions. 

Led by Professor Hyungjun Kim, the team identified structural phase transitions in the electric double layer. They explained why the electrical storage capacity changes shape based on electrolyte concentration – from a camel shape with two peaks to a bell shape with one peak. 

Through simulations and experiments, they found that at the cathode, water molecules align uniformly, while at the anode, negatively charged particles densely accumulate. These two processes create peaks in the capacitance curve which merge as electrolyte concentration rises, transforming the graph shape. 

The researchers also presented a phase diagram showing how the structure changes with voltage and electrolyte concentration, validated through real-time experiments. They emphasized the study's importance in understanding and controlling microscopic reactions to enhance energy technology performance.


Reference
by Sadie Harley, 
Electric double layer unlocks molecular switch behind battery and hydrogen reactions
Available at https://phys.org/news/2026-05-electric-layer-molecular-battery-hydrogen.html
(Assessed: 12th May 2026)