Lithium is one element that is good for making batteries, but it is not the only one. Flouride — the most electro-negative element in the periodic table — is also quite suitable for the task. In fact, fluoride batteries are capable of being 10 times more energy dense than lithium batteries. But until now, they needed to be heated to 150° Celsius (300° F for those living in former British colonies) in order to function.
A joint research team composed of engineers from Honda, NASA, and Caltech solved that problem by creating a new liquid electrolyte they call BTFE that lets fluoride dissolve at room temperature, according to Engadget. When used in a prototype battery composed of copper, lanthanum, and fluorine, the new battery was able to be discharged and recharged at room temperature. The prototype also has a “more favorable environmental footprint” than a lithium battery, according to Honda. No word on how well it performs in winter when the thermometer is well below “room temperature.”
Can you imagine what a battery with 10 times the energy density of current batteries could do for the driving range of electric cars? The prospects are exciting, no doubt about it. But there are a few hurdles to be cleared first. For one thing, the anode and cathode of the prototype battery tend to dissolve completely in the electrolyte.
That’s a problem, but the team is hard at work trying to find a solution. If they can solve the high operating temperature conundrum, making anodes and cathodes that don’t dissolve should be child’s play.
Making breakthroughs in the lab is one thing. Turning those breakthroughs into products that are easy to manufacture and commercially feasible is another thing entirely. Don’t look for fluoride batteries in EVs any time soon. Many laboratory miracles never pan out. This could be another dead end in a long line of battery research that has never gone anywhere.
Still, the prospects are tantalizing and Honda, NASA, and Caltech are not amateurs fooling around with Bunsen burners and beakers in a garage late at night. We need the next step in battery development to happen as soon as possible to move the clean energy revolution forward, but Nature does not give up her secrets on demand. Patience, grasshopper.