Fluoride-ion batteries essentially work in the opposite direction of lithium-ion cells, attracting electrons instead of shedding them. Flouride (the ionized version of fluorine) is an interesting battery material because it has a low atomic weight and very high capacity to store electrons. However, to do that, you have to dissolve the fluoride ions into an electrolyte, and researchers have found that it only works with solid electrolytes heated to high temperatures.
Read More