Last year's issue with the Samsung Galaxy Note 7 fires and explosions was due to the lithium-ion batteries inside the smartphone undergoing a thermal runaway. The result? A total recall of the phones at a huge cost to the Korean electronics manufacturer. Researchers at Stanford University believe that they have a solution: lithium-ion batteries with a built-in "fire extinguisher".
Li-ion batteries have plastic fibers that keep negative and positive electrodes in the batteries separated. In a thermal runaway, this material tends to catch fire and exacerbate the situation. What the researchers did was add a compound called triphenyl phosphate to those fibers. The chemical is often used as a flame retardant for electronics, and in this situation, if a battery's internal temperature reaches 150°C the plastic fibers would melt and release the chemical. The researchers found that this method could keep batteries from burning up in as little as 0.4 seconds.
Other teams have tried to build similar fire-extinguishing features into batteries, but in all cases the battery performance was reduced. The Stanford team's design doesn't have the same effect and under normal conditions, the chemical won't be released. Future research will ensure that overcharging or deep discharging of the batteries doesn't activate the triphenyl phosphate.
Considering the huge financial impact the Samsung recall had on the company's smartphone business, building this technology into future devices from Apple could prevent a similar issue from ever happening.