Making a safer lithium-ion battery

The lithium-ion batteries in our electronic devices use organic electrolytes to help store charge. The problem is that these electrolytes are flammable. Li-ion batteries that replace those electrolytes with water-based versions remove the risk of explosions but don’t perform as well.

To tackle this shortcoming, a team of researchers led by the University of Maryland’s Chunsheng Wang and the U.S. Army Research Lab’s Kang Xu have developed a fluorinated polymer coating that protects the anode in aqueous batteries. By shielding the anode from degradation by the water-based electrolyte, the coating enables the batteries to reach 4.0 V—the voltage level of today’s commercial Li-ion batteries (Joule 2017, DOI: 10.1016/j.joule.2017.08.009).