In an attempt to find more sustainable and lasting sources of energy, scientists are developing a battery for electric vehicles that has the potential of lasting up to 10 times longer than any lithium ion battery on the market. (Image of the different components of a fluoride battery Honda)
Since the 1990s, the lithium battery has been the best option for portable equipment or even electric vehicles. The lithium-ion battery replaced its predecessor, the nickel battery, thanks to its lightweight and great electrochemical potential. However, with the advances in technology, the lithium-ion battery cannot keep up with the needs when it comes to mobile energy sources. Among its many drawbacks, the lithium battery ages quickly. Whether it has been used or not, the battery tends to fail after 2-3 years. The lithium battery is also expensive to make: it costs 40 percent more to make lithium than to make nickel batteries. Lithium batteries are also unsafe to operate without a protection circuit. To address those concerns and find a better alternative to lithium batteries, researchers have been experimenting with a few other metals, and they discover one that is similar to the lithium but with more potential.
Considered the doppelganger of lithium, fluoride is the new option to make more reliable batteries. While lithium is the most positive metal on the Mendeleev chart, fluoride is the most negatively charged. Many people know fluoride as one of the ingredients in most toothpaste. But, fluoride is actually an ionized form of fluorine, and as a negatively charged metal, it has the power to store more energy than lithium could. For that reason, a team of researchers composed of scientists from California Institute of Technology, the Honda Research Institute Inc, Lawrence Berkeley National Laboratory and the Jet Propulsion Laboratory think it can replace lithium battery in electric vehicles that travel long distances. The research team has even secured two patents in the United States for their finding about fluoride battery.
To make a battery, scientists need an electrolyte (preferably in liquid form) in which the ions of the base element (lithium or fluorine) will dissolve to facilitate their movements between the anode and cathode. However, the challenge was that early fluoride batteries could only work with a solid electrolyte which means that they could only be used in high temperatures. To overcome that challenge, the team of researchers turned to a new electrolyte called BTFE or Bis (2,2,2 TriFluoroEthyl) ether which will allow fluoride ions to dissolve at room temperature. BTFE is a combination of multiple groups of chemicals arranged in a way that the molecule is mostly positively charged and therefore can freely interact with fluoride’s ions. That is just the beginning of the journey to long-lasting batteries.
As researchers tested the new battery, they realized that the new-found electrolyte is not really stable at high voltage. So, they have been testing some other solvents like “glyme” molecules that could make the solution more stable and functioning at high voltage. During the tests, the team is also working on stabilizing the cathode and the anode of the fluoride battery. Hopefully, the world will soon enjoy the fruits of their hard work.
Have a story tip? Message me at: cabe(at)element14(dot)com