Tiny capsules release flame retardant when temperatures get too hot
Kai Liu et al/Science Advances 2017
Hoverboards and certain cell phones powered by lithium-ion batteries occasionally go up in flames. Scientists now have a new plan for squelching these fires before they flare out of control: incorporating a flame retardant in the battery that’s released if temperatures get too toasty.
Within lithium-ion batteries, ions travel between positive and negative electrodes through a liquid called an electrolyte. But commonly used electrolytes are highly flammable. And if a short circuit in the battery produces enough heat, the electrolyte can ignite.
Simply adding a flame retardant to the electrolyte makes the battery less efficient. So scientists from Stanford University created a “smart” sheet of tiny fibers containing flame retardant, which could be inserted between a battery’s electrodes, the researchers report January 13 in Science Advances.
Each fiber is reminiscent of