New Nonflammable Electrolyte for Lithium-Ion Batteries
Lithium-ion batteries are almost everywhere in our lives, as they power our mobile devices as well as electric cars and airplane electronics. Due to the electrolyte used inside of them, all of these batteries are at risk of spontaneously combusting, though smaller batteries are much less at risk than larger ones. Researchers at the University of North Carolina at Chapel Hill have recently discovered a new polymer that could be used as an electrolyte that is nonflammable, and thus will not allow a battery to catch on fire.
In simplest terms, a battery is made of two electrodes and an electrolyte that connects them. The electrolyte serves as a medium for ions to travel between the electrodes, where they either release or obtain energy. The typical electrolyte used in lithium-ion batteries is flammable, so if a battery heats up too much, such as from an overcharge, there is a risk of it catching on fire. What the North Carolina researchers have discovered is that perfluoropolyether, or PFPE, is able to contain transport lithium-ions. This polymer has been used for years as a heavy-duty lubricant and to keep marine life from attaching to the bottom of ships, but the researchers decided to try it as an electrolyte after recognizing its structure is similar to that of a polymeric electrolyte being studied for lithium-ion batteries.
The researchers are now focusing on optimizing the electrolyte's conductivity and improving battery cycling. This research must be done for it to enter commercial batteries, and may also allow it to operate in extremely cold environments.