Name: 超級電容器能否充分發揮其潛力......與瀉藥？ (Could Ultracapacitors Realize Their Full Potential...With Laxatives?)
Uploaded: 2021-01-14T09:58:50.000Z
Duration: 4 min 47 s
Description: 【看影片學英語】數萬部 YouTube 影片，搭配英漢字典即點即查，輕鬆掌握單字發音與用法，長久累積看電影不必再看字幕。

Supercapacitors present an amazing opportunity to move away from batteries

and into a world where almost instant charging is the norm.

But their drawbacks mean we can’t use them widely...yet.

Experiments with a new class of materials that are related to soap and laxatives (yes, laxatives)

could bring us one step closer to a world with no more pesky chemical batteries.

Many batteries we’re familiar with are chemical,

which means they use some kind of charged chemical, like lithium, to store energy.

Lithium ion batteries are in everything from your phone and your laptop to electric cars,

but they’ve got some downsides. You’ve gotta wait ages for them to charge.

They start degrading basically as soon as they leave the factory,

and they’re very expensive to replace because they’re super resource intensive—

which also means they’re really not great for the environment.

They also contain highly flammable electrolytes, meaning they pose a safety risk.

I’m sure we all remember the exploding hoverboards of several years back.

These are issues for consumer electronics, yes,

but also means there are some serious restrictions for using these kinds of batteries in say, our energy grid.

Enter an excellent alternative: supercapacitors.

And just to be clear—supercapacitors are the same concept as capacitors,

which we use in many products today, just with some materials added to help them hold more charge.

Instead of chemical energy like batteries,

capacitors store energy in the form of static electricity:

when you touch someone after shuffling across the carpet in your socks.

Supercapacitors consist of two electrode plates soaked in a liquid electrolyte, separated by an insulator.

Apply a voltage, and voilá, opposite electric charges build up on the plates, creating an electric double-layer,

allowing them to store more energy than regular capacitors.

So a supercapacitor’s energy is stored in its electric field, whereas a battery’s is stored in its chemical makeup.

There’s a key thing to understand here when we talk about the difference between batteries

and supercapacitors: energy density vs. power density.

Energy density is the amount of energy that can be stored in a given mass,

whereas power density is how fast that energy can be discharged.

So supercapacitors have a much higher power density than batteries,

meaning they can pack a real punch of energy real fast when you need them to.

But they also have a much lower energy density than chemical batteries,

meaning they can store less energy overall.

supercapacitors can be charged in seconds or minutes,

rather than the hours it can take to charge a battery as big as the one in your electric car.

These trade-offs exist because supercapacitors can only store as much energy as they can hold

at the interface of their electrodes and their electrolyte.

Picture it like this: if a battery is a sponge, full of energy,

a supercapacitor is only able to use the surface of its sponge.

Sure, you can get the water out faster...but it holds less water.

This has been the main thing keeping supercapacitors from becoming our energy storage of choice—

they just don’t hold enough energy to reasonably power the stuff we use every day.

The researchers are calling them SAILs, short for surface-active ionic liquids,

and you may be surprised to hear that their molecular components are also found in something

this new class of electrolytes contain molecules that are dipolar,

meaning that their heads and tails have opposite charges.

This means that unlike conventional electrolyte materials,

these ionic liquids can self assemble into a bi-layer structure, a little bit like a sandwich.

And their charge and the way they assemble is the crucial part.

The dense layers of charged ions at the surface of the electrode allow them to store much more energy...

These supercapacitors still require certain temperatures and voltages

to achieve their impressive leap in energy storage.

The researchers also emphasize the need to keep developing this technology,

and entire systems that incorporate SAILs to make supercapacitors practical on a larger scale.

But this work is hugely exciting and could take us one step closer to a new era

cheaper, and more environmentally friendly energy storage...

hopefully changing the way we charge forever.

For more info on supercapacitor technology, check out this video here,

and subscribe to Seeker to make sure you stay up to speed with all your technological breakthroughs.

If there’s another one you want to see us cover, leave it in the comments down below.

As always, thanks so much for watching—and we’ll see you next time.