With a little work, the abundant metal could replace lithium in modern batteries.
A recently synthesized chemical offers the promise of an entirely new type of battery: calcium-based, as opposed to the modern batteries that rely on lithium.
Across the globe, scientists are interested in what's coming after lithium batteries. The rechargeable batteries have become the dominant power source in any number of consumer electronics, from phones to cars. Research predicts that the global lithium ion battery market will be worth $ 81.65 billion by 2021.
But with that growth comes a suite of challenges. There's the limited physical nature of lithium's output (primarily in Latin America and China), but also from the environmental havoc its extraction, which often requires heavy water consumption, leaves on the surrounding areas.
Calcium has the potential to act as a replacement. It's already used in lead acid batteries, which are often seen in automotive starter motors. It's the fifth most abundant element in Earth's crust and the third most abundant metal, with equal geographical resource distribution around the globe. Calcium also lacks lithium's troublesome trait of catching fire.
The challenge for researchers has been finding a workable electrolyte. Within batteries, an electrolyte is a catalyst that allows the battery to move ions from one place to another. For a battery to work, it needs to transfer ions from its cathode to its anode. Electrolytes come in many varieties, including soluble salts, acids, or other bases in liquid, gelled, and dry formats.
Researchers at Helmholtz Institute Ulm in Germany used a salt here. More specifically, they "reacted a calcium compound with a fluorine-containing compound to create a new type of calcium salt," according to a description in Nature, which distributes the Energy & Environmental journal in which the research was first published.
According to the team's paper, the new electrolyte has "wide electrochemical window and good chemical stability, which may pave the way for high-energy Ca batteries."
There's still a way to go in the research progress, with the team saying that "further improvement will be carried out by modifying the electrolyte composition e.g. solvent, concentration and additive." Now that an electrolyte has been discovered, in other words, it can be improved.
Another possible replacement for lithium batteries is iron.