When baby boomers were kids their mothers gave them calcium tablets for strong teeth. This made sense seeing as we find calcium in the fossilized remains of sea shells. Moreover, the reactive metal is the third most abundant metal in Earth’s crust after iron and aluminum. Popular Mechanics posed the question could calcium metal be a key battery material. We would have an abundant supply if it replaced lithium.
Could Calcium Metal Solve the Problem of Lithium Fires Perhaps …

It’s a good question. Lithium metal ignites in the presence of air as most school kids know. Calcium does not, try lighting a seashell. Lithium battery fires are the elephant in the kitchen of the industry.
Sure they only happen occasionally and there’s always a technical explanation. Calcium by comparison does not need huge amounts of water to extract it from its source either. Could calcium metal therefore act as a lithium replacement? We already find it in lead starter battery plates where it replaces antimony. That’s because it resists corrosion, and withstands high temperatures better.
However the Problem is Finding a Suitable Companion Electrolyte
Electrolyte in batteries facilitates the safe exchange of ions between cathodes and anodes. This phenomenon is a necessary condition for the flow of electricity through connected devices.

In September 2019 Popular Mechanics reported scientists at Germany’s Helmholtz Institute have found salt may be the answer. Apparently, “they reacted a calcium compound with a fluorine-containing compound to create a new type of calcium salt.” This appears to have a “wide energy window with good chemical stability” so this just might be the way forward.
As always, there are cautionary announcements. There is still a way to go in the research process says Popular Mechanics. We observe from the side-lines while wondering could calcium metal be the answer. We are always hopeful someone will discover the ideal battery companion for our renewable energy dream.
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Preview Image: Calcium Metal in Argon Gas