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  • Researchers recently and quite accidentally discovered something that could change the

  • whole electric car ballgame.

  • If their predictions are accurate, we could one day live in a world where cars can be

  • fully charged in minutes instead of hours, and their power storage units would last decades

  • instead of years.

  • What is this tantalizing breakthrough you ask?

  • A monumental leap forward in capacitor technology.

  • Many of the current drawbacks of electric cars stem from how batteries work.

  • Batteries rely on chemical reactions, which means for a lithium-ion battery to release

  • energy you have to wait for the lithium to shuffle through an electrolyte, and when you

  • want to store energy you have to wait for the lithium to shuffle back.

  • Lithium-ion batteries also degrade, and replacing one in an electric car would be enormously

  • expensive.

  • In contrast capacitors store static electricity, like what builds up on a balloon as you rub

  • it on your hair.

  • Capacitors can be as simple as two metal plates separated by air.

  • When a current is applied to the plates, a positive charge builds up on one plate and

  • a negative charge builds up on the other.

  • No electrolytes, no shuffling ions, just electrons on a plate waiting to pounce like a caged

  • lion.

  • As a result capacitor can be fully charged almost instantly, and since they can also

  • deliver energy quickly, that means capacitors can provide more power than batteries.

  • They are much more durable than lithium-ion batteries too, lasting through tons of charge

  • and discharge cycles with little degradation.

  • There is an achilles heel: they just can't hold very much energy.

  • There are tricks to squeeze more charge onto the plates, like increasing their surface

  • area and reducing the distance between them by swapping out the air with a thin insulator.

  • Do that and you've created a supercapacitor, but even then, the best supercapacitors today

  • hold just 10 watt-hours per kilogram, about 5% of the energy of a lithium ion battery

  • of the same weight.

  • You would need a capacitor the size of a bus to get any real use out of it.

  • As it happens in 2010 Shanghai experimented with electric buses powered by capacitors

  • that charged up every couple of stops.

  • That's a pretty clever use for them, but if you want a personal car smaller than a

  • bus that can travel more than five miles without stopping, capacitors are going to have to

  • step up their game.

  • Bizarrely the big breakthrough in supercapacitor technology may come fromcontact lenses?

  • Soft contacts use a polymer mesh that can swell up and store water.

  • One of the original inventors has been tinkering with the polymer ever since, and found that

  • adding different elements imbues it with different properties, like the ability to store electricity.

  • Actually they were shocked at just how much energy the polymer could store.

  • A 2016 test of the little blue material found it stored 100 times the energy the researchers

  • expected.

  • Since then they've been testing the material to see if it works in real world conditions,

  • and after 14 months of research have concluded that the material could eventually store 180

  • watt-hours per kilogram, putting it almost on par with battery energy density, at least

  • by weight.

  • The supercapacitors could be quite a bit more voluminous, perhaps 30% bigger than an equivalent

  • battery.

  • Still, they'd be faster to charge, cheaper to make, and wouldn't have the risk of catching

  • fire since they'd be mostly water.

  • They could also have applications outside of cars, like storing energy for when it's

  • in high demand, or when renewable sources aren't generating electricity.

  • For now regular old chemical batteries are still the best fit for electric cars.

  • But if this is the breakthrough the researchers believe it is, batteries could be on their

  • way out in the next decade.

  • In a weird way, soft contact lenses may help us see a brighter future.

  • If you like what you see don't forget to subscribe.

  • Just because capacitors are improving doesn't mean we're not developing new and better

  • batteries too.

  • Like a squishy battery!

  • You can learn more about that here!

  • None other than Elon Musk himself has said that supercapacitors are the future of electric

  • cars.

  • But he also thought a tiny submarine would helpso ya know,

  • grain of salt and all that.

  • Thanks for watching and I'll see you next time on Seeker.

Researchers recently and quite accidentally discovered something that could change the

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How Supercapacitors Could Make Batteries a Thing of the Past

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    joey joey posted on 2021/04/12
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