Scientists create quick-charging hybrid supercapacitors

April 1, 2015 by Shaun Mason
The new hybrid supercapacitor developed at UCLA stores large amounts of energy, recharges quickly and can last for more than 10,000 recharge cycles. Credit: UCLA California NanoSystems Institute

The dramatic rise of smartphones, tablets, laptops and other personal and portable electronics has brought battery technology to the forefront of electronics research. Even as devices have improved by leaps and bounds, the slow pace of battery development has held back technological progress.

Now, researchers at UCLA's California NanoSystems Institute have successfully combined two nanomaterials to create a new energy storage medium that combines the best qualities of batteries and supercapacitors.

Supercapacitors are electrochemical components that can charge in seconds rather than hours and can be used for 1 million recharge cycles. Unlike batteries, however, they do not store enough power to run our computers and smartphones.

The new hybrid supercapacitor stores large amounts of energy, recharges quickly and can last for more than 10,000 recharge cycles. The CNSI scientists also created a microsupercapacitor that is small enough to fit in wearable or implantable devices. Just one-fifth the thickness of a sheet of paper, it is capable of holding more than twice as much charge as a typical thin-film .

The study, led by Richard Kaner, distinguished professor of chemistry and biochemistry and materials science and engineering, and Maher El-Kady, a postdoctoral scholar, was published in the Proceedings of the National Academy of Sciences.

"The microsupercapacitor is a new evolving configuration, a very small rechargeable power source with a much higher capacity than previous lithium thin-film microbatteries," El-Kady said.

The new components combine laser-scribed graphene, or LSG—a material that can hold an , is very conductive, and charges and recharges very quickly—with manganese dioxide, which is currently used in alkaline batteries because it holds a lot of charge and is cheap and plentiful. They can be fabricated without the need for extreme temperatures or the expensive "dry rooms" required to produce today's supercapacitors.

"Let's say you wanted to put a small amount of electrical current into an adhesive bandage for drug release or healing assistance technology," Kaner said. "The microsupercapacitor is so thin you could put it inside the bandage to supply the current. You could also recharge it quickly and use it for a very long time."

The researchers found that the supercapacitor could quickly store electrical charge generated by a solar cell during the day, hold the charge until evening and then power an LED overnight, showing promise for off-grid street lighting.

"The LSG–manganese-dioxide capacitors can store as much electrical charge as a , yet can be recharged in seconds, and they store about six times the capacity of state-of-the-art commercially available supercapacitors," Kaner said. "This scalable approach for fabricating compact, reliable, energy-dense shows a great deal of promise in real-world applications, and we're very excited about the possibilities for greatly improving personal electronics technology in the near future."

Explore further: Laser-induced graphene 'super' for electronics

More information: Engineering three-dimensional hybrid supercapacitors and microsupercapacitors for high-performance integrated energy storage, PNAS 2015 ; published ahead of print March 23, 2015, DOI: 10.1073/pnas.1420398112

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Eikka
3.5 / 5 (11) Apr 01, 2015
Warning. The article talks about charge in the strict electrical sense instead of the colloquial "charge" as in energy.

The actual energy density of the device is 22...42 Wh/l which is still ten times worse than lithium-ion batteries, and half as much to a typical automotive lead-acid battery. Each cell is 2 Volts.

There's not enough information available to tell the energy density by mass. Probably because they're just testing bare cells without proper packaging.
THEKPV-SOLAR-SUPER-BIKE
5 / 5 (4) Apr 01, 2015
.. `Tour said that while thin-film lithium ion batteries are able to store more energy, LIG supercapacitors of the same size offer three times the performance in power (the speed at which energy flows). And the LIG devices can easily scale up for increased capacity.`
MR166
1 / 5 (2) Apr 01, 2015
Well I don't think that a super cap could ever power and entire car. You would need about a 100,000 farad 50 volt cap to store 27KWH. That sort of cap is a loooong way off in the future.
Bongstar420
5 / 5 (2) Apr 01, 2015
Sorry...I was turned on to this idea years ago for cars.

http://arxiv.org/...1548.pdf
Mike_Massen
4.4 / 5 (7) Apr 02, 2015
MR166 offered
Well I don't think that a super cap could ever power and entire car. You would need about a 100,000 farad 50 volt cap to store 27KWH. That sort of cap is a loooong way off in the future
Got a few caps, @3000F & 2.7V, bearing in mind a 10KWHr Li-batt pack was observed in use by a goods van ostensibly for acceleration aid with regen braking. As example for that energy (& using supercaps only) you need:-
36MJ from 10Kw x 3600, then have to decide how to string the caps for what is a practical motor Volts Eg ~390
& consideration of motor/controller efficiency but is effectively constrained by how much power to accelerate a small goods van, Eg ~25Kw... btw That only allows 24mins for max 25Kw ie Prob enough for few goes as long given a classic accel (with diesel) is ~10secs to 80Km/hr local highway speeds & yes I know u don't get full regen etc etc
So, 36MJ=0.5C390^2 gives caps of say 475F BUT, in series to get 390v, roundup to make it 145 caps
cont
Mike_Massen
3.7 / 5 (3) Apr 02, 2015
continues
@MR166
So, 36MJ=0.5C390^2 gives caps of say 475F BUT, in series to get 390v, roundup to make it 145 caps. Those caps in series only get to 21F but you need to get to 475F, so thats 23 strings in parallel with each single strip having 145 caps. So total number of 3000F 2.7v caps is 23x145 = 3335 caps.

Given ea cap, in 1000 off can be procured for some $20 or so each, thats $66,700 AUD just for caps !

Therefore. Batteries are more cost effective but, suffer limitation of depth of discharge & unable to take as much charge current as caps & in any case regen isnt that efficient. So for short term use how about deep discharge lead acid cheapies...But say allowing for 50% depth of discharge makes for a 20KwHr battery bank (2x10). Eg for cheap 60AH batteries gives a motor volts of 333, prob close enough, which gives say 28 x 12v nom. batteries. These can be had (new) for approx AUD$ 110 gives AUD$ 3080, ie Quite doable esp as diesel here is ~$ 1.38c/l
Accata
5 / 5 (1) Apr 02, 2015
laser-scribed graphene, or LSG
This is the weakest portion of the above technology - this is a thin layer technology, unable to work at larger scale. The graphene layer could be indeed replaced with normal graphite or active carbon dust, commonly used in normal (hybrid) supercapacitors, but these bulk electrodes are prone to degradation during discharge cycles and also their perfomance is far worse than this one of thin layers (only portion of graphite gets actually involved into charge storage due to its poor electrical contact). This technology could find therefore usage in thin layer or fabric woven applications only.
MR166
1 / 5 (1) Apr 02, 2015
Right at this moment Ultra Caps are too big and too heavy to be used for transportation. They need to improve about 10x in both parameters. Also they are only rated for about 10 years of life.
Eikka
2.8 / 5 (6) Apr 02, 2015
The main reason why you won't see capacitors powering cars is because they have a tremendously high self-discharge rate compared to modern batteries.

They leak.

The best of the best retain their charge for little under a month, so they're hardly any better than the old NiCd cells. It may sound insignificant, but if a Nissan Leaf were to have such leakage, you'd pay about $1000 more in electricity over the life of the vehicle. Parasitic energy use is already a big problem with EVs. The Tesla Model S for example consumes about 1.1 kWh a day just sitting in the garage because of all the stand-by electronics.

It gets worse the more energy you try to stuff in, because the rate of leakage increases with increasing capacitance (surface area) and increasing voltage. Temperature also increases leakage.

gkam
2.7 / 5 (7) Apr 02, 2015
Eikka is right. I'm going back to a donkey and a wood fire in the middle of the hut.
MR166
1 / 5 (1) Apr 02, 2015
"The Tesla Model S for example consumes about 1.1 kWh a day just sitting in the garage because of all the stand-by electronics."

I find that hard to believe unless the batteries need to be kept at a certain temperature. 1.1KWH a month is more like it and even that is high.

You are correct about the super cap leakage. A 3000F cap leaks about .005 amps of current. That is enough leakage to discharge it in well under a month. A Tesla will lose about half of it's charge in a month.
MR166
1 / 5 (4) Apr 02, 2015
Guess what people the Tesla is just more Green BS!!!!

It takes 4.5KWH/day just to keep it sitting in your garage.

http://www.popsci...-remains
Eikka
2.6 / 5 (5) Apr 02, 2015
I find that hard to believe unless the batteries need to be kept at a certain temperature. 1.1KWH a month is more like it and even that is high.


Tesla has made some "creative" solutions in their design, which require some of the computers to remain on all the time or you can't even open the doors. They initially had a software glitch that put the car permanently to sleep after shutdown so they disabled sleep mode in a software update, and that made the car consume up to 5 kWh a day just sitting idle. Then they patched it and got it down to about 1 kWh.

When completely shut down to deep sleep, the car should consume about 0.17 kWh a day (7 Watts), which is what the battery management system consumes to monitor and maintain the cells.

gkam
2.7 / 5 (7) Apr 02, 2015
166 does not get an electric car. He'll have to drive a polluter.
Eikka
2.6 / 5 (5) Apr 02, 2015
Eikka is right. I'm going back to a donkey and a wood fire in the middle of the hut.


Don't be childish. You don't even own a Tesla car.
Eikka
2.6 / 5 (5) Apr 02, 2015
Guess what people the Tesla is just more Green BS!!!!

It takes 4.5KWH/day just to keep it sitting in your garage.

http://www.popsci...-remains


That case was down to a faulty DC-DC converter at the 12 Volt system, that kept running despite the car being powered down.
MR166
3 / 5 (2) Apr 02, 2015
Well, having thought about it a little more even even say 3 KWH per day is only the equivalent of running a 100 W light bulb 24/7. That is really not that bad.
Mike_Massen
4.3 / 5 (6) Apr 02, 2015
This so called "Vampire Drain", it should be possible & from my experience on Remote Area Power Systems (RAPS) from 1990 - 1998, once u have charged up cells there is no particular need to monitor them for voltage unless there is particularly high or low cell/ambient temperature. Having a thirsty piece of electronics consuming $ just watching is a "pretty feeble design". Besides with a properly embedded design focusing on "min power" Eg Raspberry or MPS TI series microprocessors etc background consumption SHOULD be less than 5 Watts easy !

From that perspective it SHOULD in my humble opinion be able to run monitoring system upon running car inday light from a roof-top solar panel supplying a mere ~100W !

I've worked on 40nA (nano amp) monitoring systems reliably with one of my designs for Carbon Monoxide & with RF paging as well for less than 10W continuous, FFS did designers have a bloated OS/hardware running windows just to measure volts FFS - ugh, yuck ! :-(
Eikka
2 / 5 (4) Apr 02, 2015
Well, having thought about it a little more even even say 3 KWH per day is only the equivalent of running a 100 W light bulb 24/7. That is really not that bad.


It is a lot of energy. For starters, it costs you ~$120 a year in electricity, but more importantly, it is equivalent of putting nearly 3,000 miles more on the battery every year.

Reason being that the charge controller can't and won't trickle charge lithium-ion batteries. When plugged in, the BMS will cycle the battery between 97% and 100% as it drains.

So having a thirsty piece of electronics consuming power just watching is a "pretty feeble design".


Lithium-ion cells have a necessary active low-voltage safety latch that prevents them from going below 2.3 - 2.5 Volts per cell. Otherwise you create a fire hazard as the cells become chemically unstable. This creates a rather insignificant power drain, but the Tesla battery has thousands of standard small cells.
Eikka
2 / 5 (4) Apr 02, 2015
From that perspective it SHOULD in my humble opinion be able to run monitoring system upon running car inday light from a roof-top solar panel supplying a mere ~100W !


The Chevrolet Volt / Opel Ampera has neglible self-discharge because the computers are switched hard off when the ignition is turned off. Consequently, it takes 3-4 seconds to boot them back up before the car starts. The Tesla is like the iPhone of cars in that sense - they're sacrificing practical sensibilities for user experience.

Plus, GM uses larger prismatic pouch-type battery cells instead of standard cylindrical cells to have a fewer number of them as compared to Tesla's 7,104 cells in a battery. That simplifies the battery management system immensely.

gkam
2.7 / 5 (7) Apr 02, 2015
It will be interesting to see how it all shakes out between batteries fuel cells and the integration of all the systems. I think it will be in the granularity, with essentially micro-grids divided up for self-support, normally interconnected to everyone else.
MR166
1 / 5 (1) Apr 02, 2015
Here in Connecticut we pay 22 cents/kwh so 3kwh/day does add up quickly. But if you were using an EV every day an extra 3kwh would not be that noticeable in the overall picture.

Anyhoo, I am glad to see that the problem has been solved.
gkam
2.3 / 5 (6) Apr 02, 2015
PV paint will help in the future of EVs, perhaps. Everybody will be looking to stay away from Summer shade!
Eikka
2 / 5 (4) Apr 02, 2015
PV paint will help in the future of EVs, perhaps. Everybody will be looking to stay away from Summer shade!


First you have to invent some.

But if you were using an EV every day an extra 3kwh would not be that noticeable in the overall picture.


In practical terms it means you need to swap your battery for a newer one about 3 years earlier than you otherwise would have, which costs you several thousands of dollars more.
gkam
3 / 5 (8) Apr 02, 2015
gkam
2.7 / 5 (7) Apr 02, 2015
Eikka will want to read this:

http://phys.org/n...tml#nRlv

Really. It is an Achilles' Heel of the Electric/Electronic world.
Mike_Massen
4.2 / 5 (5) Apr 02, 2015
Eikka offered
I said
So having a thirsty piece of electronics consuming power just watching is a "pretty feeble design"
Lithium-ion cells have a necessary active low-voltage safety latch that prevents them from going below 2.3 - 2.5 Volts per cell. Otherwise you create a fire hazard as the cells become chemically unstable. This creates a rather insignificant power drain, but the Tesla battery has thousands of standard small cells
Sure, perhaps. Context however, my post, which Eikka may have missed, is that this is after cells have been charged (& monitored) ostensibly in readiness for next use

As such charging on return end of day, is new paradigm, then filling the tank ea week or so as is case with petroleum.

Upon reflection, passive electronics which monitor multiple cells, with benefit CMOS op-amps/uP should be able to monitor at <5W - then if & only if there is exception a comm system can be initiated which doesn't need any more than 500mS to Boot !
Eikka
3 / 5 (6) Apr 02, 2015
Eikka:

http://www.alibab...int.html


Your link leads to various car paints in metallic colours, acrylic and PolyVinyl paints. Not PhotoVoltaic paints.

The other link you refer to says:

"The best light-to-energy conversion efficiency we've reached so far is 1 percent"


Also, cadmium in paint is kinda toxic, problematic for recycling and an environmental hazard. Somehow I don't see paint-on solar panels becoming a thing with the current direction of development, and even that article is four years old now - if there was something to it, we would have heard of it by now.

Really. It is an Achilles' Heel of the Electric/Electronic world.


"The uncoordinated proliferation of distributed energy resources will wreak havoc at scale,"

As I've been saying.

The next question is, what does "coordination" imply? Will people for example shy away from electric cars because utilites are forced to limit the recharging rate?
gkam
2.1 / 5 (7) Apr 02, 2015
Why do you try to invent problems? My gosh, you must have nightmares.

I showed you a real one to solve, but you try to invent another one, . . from pure paranoia?
Eikka
3 / 5 (6) Apr 02, 2015
Why do you try to invent problems? My gosh, you must have nightmares.

I showed you a real one to solve, but you try to invent another one, . . from pure paranoia?


I'm not sure what or who you're referring to. Would you elaborate?
Feldagast
1 / 5 (1) Apr 05, 2015
Wait till they shut down all the coal plants and the cost of electricity "necessarily" skyrockets, hmm who said that?
gkam
1.8 / 5 (5) Apr 06, 2015
It is time the owners of coal plants started PAYING for the damage they inflict on life.

ALL of US are saying that.
MR166
1 / 5 (4) Apr 06, 2015
"It is time the owners of coal plants started PAYING for the damage they inflict on life.

ALL of US are saying that."

So Gcam are you saying that if you were "King" you would shut down all coal plants in the next year? If not, why not if they are causing so much harm to the environment?
gkam
2.3 / 5 (6) Apr 06, 2015
Show me where I said that.

Then, stop making really stupid suppositions.
MR166
1 / 5 (4) Apr 06, 2015
Yes Gcam you are a typical progressive. You want fossil fuels to pay penalties for their existence but you do not want to be responsible for the costs to society if they are banned.
Eikka
2.6 / 5 (5) Apr 08, 2015
It is time the owners of coal plants started PAYING for the damage they inflict on life.
ALL of US are saying that.


You do understand what you're asking for, right?

Coal provides 30% of the global primary energy. If you remove it, you're effectively removing a third of the global productive output in every sense from food to heat to housing and raw materials.

Likewise, increasing the cost of coal by say... we'll let's take the EPA estimate of 4x real cost, you'd make every thing on this planet cost twice as much. That means a couple billion people would die directly of poverty and the Chinese couldn't sell you cheap solar panels and wind turbines. Society would grind to a standstill.

The sole reason we are able to discuss here online and butt heads over what's the best way to build the future, or to be able to build a future at all, is because coal is still cheap. We're simply letting the problems accumulate because we can't yet afford to do anything about them.

MR166
1 / 5 (4) Apr 08, 2015
Eikka most of the progressives on this board are what's known as "Useful Idiots". They are mere pawns of the real powers that want to create world chaos in order to create the one world government also known as the "New World Order". Energy and food shortages are all part of the plan. I know, this all sounds a little far fetched but how else does one explain such a concerted effort to destroy food producing crop land via bio-fuels and destroy the fossil fuel industry decades before there is a technology available to replace it.
gkam
1.7 / 5 (6) Apr 08, 2015
How nice of you to let others get sick and die so you can have cheap solar cells.

If coal were much more expensive, we would not put up with it, and would already have better substitutes. It is the cheapness which makes Human life cheap.

gkam
1 / 5 (5) Apr 08, 2015
"They are mere pawns of the real powers that want to create world chaos in order to create the one world government also known as the "New World Order""
-------------------------------------------

The Bush Crime Family is not liberal, they are astounding crooks! The "New World Order" had the Bush and bin Laden families running things.

Next time you get a lecture on "The New World Order", challenge the Grand Klaxon who tells you that stuff.
MR166
3 / 5 (2) Apr 08, 2015
Gkam I am no fan of Bush 1. In reality we have not had a president and congress that were both working for the best interests of the United States and it's citizens since Kennedy. The sad excuse that we have for a government today is just shameful. If you cannot see that BOTH sides are the problem then there is no real hope for the US.
RealityCheck
3.9 / 5 (7) Apr 08, 2015
@Eikka.
Coal provides 30% of the global primary energy. If you remove it, you're effectively removing a third of the global productive output in every sense from food to heat to housing and raw materials.
It's not about removing all coal fired plants. Half will do nicely as alternatives gain traction everywhere. As for the cheapness of coal, it's a myth. The total real hidden/opportunity costs are huge. If the money spent on expensive medicines/health care etc, as well as on remediating/compensating for environmental/subsidence/water poisoning etc costs, due to mining/burning of coal was avoided and not incurred by all affected in first and third world countries, then that saved money would more than compensate for cost of alternatives in long term. Actually, alternatives would end up being cheaper, employ more and be sustainable and more distributed and less subject to exploitation for excess profits by 'monopolies' than current coal plants/mining system. Cheers.

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