Batteries aren’t that hard to make. You might have made a lemon or potato into a battery as a kids’ science project.
But lemons aren’t really cheap or long-lasting enough to become a central part of the energy economy – and we are going to need many, many more batteries as our cars and homes electrify and our grids transition to renewables.
So: beyond the humble lemon, what else can you make batteries out of? This year, scientists had a range of bizarre answers: here are six of Cosmos’ favourites.
How do batteries work?
Before diving into the ingredients of a battery, it’s worth taking a look at how they work. Our explainer on batteries will get you right into the mechanics, and where they best fit in the electricity grid.
Now you know, let’s take a look at all the bizarre things scientists could conceivably turn into batteries…
A team of Swiss researchers made a disposable battery out of paper.
The paper is printed with a couple of inks that perform the function of the battery. It’s inert until you add a few drops of water, which allows ions to move between the inks and electricity to flow.
It’s powerful enough to run a small LCD alarm clock, and can run for an hour – two hours if it’s dampened again.
2. Quantum physics
Quantum batteries are now closer to reality, with proof of the idea of superabsorption by an international team of researchers.
The discovery could pave the way for a class of batteries that charge faster the bigger they get – as well as being able to charge just from ambient light in a room.
Yep, commercial printers. According to a group of Australian and Chinese researchers, this is possible with technology they’re working on. Their battery prototypes can bend and flex, and can be made from liquids with a process that’s not unlike printing. They could also be biodegradable.
Such batteries would probably only ever be powerful enough to charge small devices – they couldn’t compete with lithium-ion to run a car. But, at least in the lab, they’re rivalling lithium-ion already at the small scale.
4. Liquid vanadium
Who says a battery has to be a solid? Redox flow batteries, which use tanks of liquid electrolyte, have great storage and longevity potential.
They’re a 40-year-old Australian invention, but as the world’s lithium resources come under strain, redox flow batteries using dissolved vanadium ions are getting more attention. In this article, we look at how they work and where they fit in the energy transition.
And while we’re on the topic of redox flow batteries…
A team of UK chemists figured out a way to make redox flow batteries with much cheaper materials – in fact, one of their materials is air!
Their prototype battery is 50-100 times cheaper than current commercial batteries in terms of energy stored – but still much more expensive in terms of power output.
Okay, this one shouldn’t be much of a surprise – chances are, you’re reading this article on a device powered by a lithium-ion battery. But can Australia do more than just mine lithium? Could we be providing more value to the battery supply chain?
A new project in the Hunter Valley will be a major test case of our resolve to become more than the world’s open-pit mine.