As the climate warms, sea levels rise and droughts, heatwaves and bushfires multiply, the need to usher in the green-energy future is increasingly urgent. But that doesn’t mean it can be done without significant challenges – not just in the economy (as it makes the changeover), but technologically and scientifically as well.
It’s a problem reminiscent of the 1970s environmental rallying cry TANSTAAFL (There ain’t no such thing as a free lunch), drawn from a 1966 novel by science fiction writer Robert A. Heinlein. All things come at a price, the idea goes, and while the price of excessive reliance on fossil fuels is increasingly evident, that doesn’t mean there aren’t going to be issues with weaning ourselves off them.
One of these “issues” is lithium.
Most of us have never seen pure lithium, and never will. In this form, it is a soft silvery-white metal that so easily corrodes it has to be kept in mineral oil to protect it from air. But we all use it: it’s the magic ingredient in the lithium-ion batteries that power everything from our smartphones and watches to electric vehicles.
Prior generations of rechargeable batteries used lead and acid, nickel-cadmium mixes, and nickel mixed with other materials. Lithium, however, is a lot less toxic, holds its charge better when not in use, and is less susceptible to developing the “battery memory” problem in which ageing batteries fail to fully recharge. But its biggest advantage is that it is a lot lighter. Lithium is element number three on the periodic table: eight times lighter than nickel, 16 times lighter than cadmium, 30 times lighter than lead.
In other words, when it comes to batteries, it packs a lot more bang for the buck (or, more precisely, the gram). “For a given weight, it
