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The Super Supercapacitor [video]

focusforwardfilms.com

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Re: The Super Supercapacitor [video]

#11

Post by hwillis »

mpweiher wrote: post #2

Very cool tech, and the manufacturing process looks doable as well. :-) Except for us poor mac-heads, how is iTunes going to make me some Graphene?? I was a bit disappointed that there weren't any numbers in the film, so I looked them up: http://www.extremetech.com/extreme/122763-graphene-supercapa... Energy density (storage capacity) does seem to be in range of Lithium Ion batteries, better than some, but still arou…

There also exist hybrid supercapacitors, which use a chemical reaction but act like capacitors. The best use of high-power capacitors is not as a replacement, its as a supplement. Current technology is not quite sufficient, but ideally it would mean that anything under a 20 minute drive could run off just the capacitor, which could(with sufficient infrastructure) charge in under a minute. It's not quite filling up on gas, but its closer.

I would like to see more investigation into turbine powered cars again, it may be more feasible now to build a car like we build trains (A prime mover generates energy for locomotive motors). I think the best way to transition from gasoline to electric would be to take advantage of existing infrastructure and make hot-swappable battery units. For medium drives you use batteries, which can be switched in a garage with a capacitor bank for short drives, or a unit with a small battery, a helicopter turbojet and a gas tank (Which, ideally, would run at a higher efficiency than an ICE).

The reason we haven't used turbines in the past as far as I know is mostly the start-up times and inability to idle. They don't really slow down, so sitting in stop and go traffic you engine is basically still on full blast. Ameliorate that with a battery and you're good to go, hopefully.

Re: The Super Supercapacitor [video]

#12

Post by lutusp »

DanWaterworth wrote: post #4

I haven't seen any mention of the efficiency. Does anyone have any numbers comparing a regular battery to a graphene supercapacitor?

They won't know until they process this first step into a working device with conductors and all the essential elements of a real storage device. But in principle, a capacitor is a much better storage device than a battery -- no chemical conversions, no limit to charge-discharge cycles, many similar advantages.

Re: The Super Supercapacitor [video]

#13

Post by jws »

acd wrote: post #3

Combine the graphene supercapacitor with Korea Advanced Institute of Science and Technology OLEV and we would soon have clean transportation in the cities. Imagine what that would do for air quality! Say that you build inductive charging points in the lanes before stop lights. The car/bus stops and charges the supercapitor. EV battery problem solved with little extra weight needed by the car. Sure a range extending h…

How about catapults, like an aircraft carrier, instead of inductive chargers? You get all your kinetic energy to road speed plus you can regeneratively charge to the limits of tire/road traction. You get the energy for at least two stops and all you need is a little someplace on the bottom of the car for the hook to engage. I'll bet intersections are more efficient too when the intersection can fire off the waiting traffic in short order.

You'll need a little faith that the intersection software won't launch you into cross traffic or pedestrians. And I'll bet you don't need red light cameras anymore once there is the threat of having a Prius launched into your driver's side door at 30mph.

Re: The Super Supercapacitor [video]

#14

Post by glogla »

lutusp wrote: post #10
Egregore wrote: post #8

In the video they show that graphene can be thrown away in compost bin safely, how is it related to all the warnings we have about nanomaterials being dangerous?

The warnings about nanomaterials are about their applications, not their mere existence. (The rational warnings, anyway.) Graphene is just a form of carbon, like graphite or diamond, neither of which is thought to be particularly hazardous. http://en.wikipedia.org/wiki/Graphene

True, but for example carbon nanotubes are also just "form of carbon" and they are great for lot of uses, but have about the same effect on human bodies as Asbestos, [1] so asking about this is legimitate.

You're right that Graphene is ok, though.

[1]: https://en.wikipedia.org/wiki/Carbon_nanotube#Toxicity

Re: The Super Supercapacitor [video]

#15

Post by btilly »

lutusp wrote: post #10
Egregore wrote: post #8

In the video they show that graphene can be thrown away in compost bin safely, how is it related to all the warnings we have about nanomaterials being dangerous?

The warnings about nanomaterials are about their applications, not their mere existence. (The rational warnings, anyway.) Graphene is just a form of carbon, like graphite or diamond, neither of which is thought to be particularly hazardous. http://en.wikipedia.org/wiki/Graphene

Not necessarily true. As http://www.scientificamerican.com/article.cfm?id=carbon-nano... explains, the impact that asbestos has on our lungs is a mechanical process, and will be caused by any kind of hard object about the same size.

A lot of nanomaterials have the potential for creating dust in this size, including ones made of pure carbon.

Re: The Super Supercapacitor [video]

#16

Post by stcredzero »

jws wrote: post #13
acd wrote: post #3

Combine the graphene supercapacitor with Korea Advanced Institute of Science and Technology OLEV and we would soon have clean transportation in the cities. Imagine what that would do for air quality! Say that you build inductive charging points in the lanes before stop lights. The car/bus stops and charges the supercapitor. EV battery problem solved with little extra weight needed by the car. Sure a range extending h…

How about catapults, like an aircraft carrier, instead of inductive chargers? You get all your kinetic energy to road speed plus you can regeneratively charge to the limits of tire/road traction. You get the energy for at least two stops and all you need is a little someplace on the bottom of the car for the hook to engage. I'll bet intersections are more efficient too when the intersection can fire off the waiting t…

I chuckle at the thought of a Prius becoming catapult ammo. Ingeniously bad and funny idea.

Re: The Super Supercapacitor [video]

#17

Post by jws »

hwillis wrote: post #11
mpweiher wrote: post #2

Very cool tech, and the manufacturing process looks doable as well. :-) Except for us poor mac-heads, how is iTunes going to make me some Graphene?? I was a bit disappointed that there weren't any numbers in the film, so I looked them up: http://www.extremetech.com/extreme/122763-graphene-supercapa... Energy density (storage capacity) does seem to be in range of Lithium Ion batteries, better than some, but still arou…

There also exist hybrid supercapacitors, which use a chemical reaction but act like capacitors. The best use of high-power capacitors is not as a replacement, its as a supplement. Current technology is not quite sufficient, but ideally it would mean that anything under a 20 minute drive could run off just the capacitor, which could(with sufficient infrastructure) charge in under a minute. It's not quite filling up on…

I believe turbines have efficiency problems as you scale them down.

Ah yes, graph here… http://www.dg.history.vt.edu/images/image5_2.gif which is from http://www.dg.history.vt.edu/ch5/turbines.html

And then notice that the smallest turbine on the plot is about two orders of magnitude larger than you need in a small car.

Re: The Super Supercapacitor [video]

#18

Post by tehwalrus »

DanWaterworth wrote: post #4

I haven't seen any mention of the efficiency. Does anyone have any numbers comparing a regular battery to a graphene supercapacitor?

hmm, I was going to jump in with "Capacitors are never more than 50% efficient, because physics" but it seems only if you charge from nothing at a constant current:

http://www.scribd.com/doc/79500452/ANALOG-SEEKrets-DC-to-Day...

(filed under "today I learned")

Re: The Super Supercapacitor [video]

#19

Post by meaty »

lutusp wrote: post #12
DanWaterworth wrote: post #4

I haven't seen any mention of the efficiency. Does anyone have any numbers comparing a regular battery to a graphene supercapacitor?

They won't know until they process this first step into a working device with conductors and all the essential elements of a real storage device. But in principle, a capacitor is a much better storage device than a battery -- no chemical conversions, no limit to charge-discharge cycles, many similar advantages.

They aren't magic. They have a relatively high self-discharge (or leakage depending on how you measure it) compared to say Li-ion/NiMh cells which means basically they piss capacity away slowly.

Don't expect your wonderful supercap car to actually be charged if you leave it sitting there for a few hours.

Re: The Super Supercapacitor [video]

#20

Post by chime »

olympus wrote: post #9
ksec wrote: post #5

Sounds like Cheap and Powerful, So what is stopping this from mass production? My Phone could help with a charging time of less then a minutes!.

From what I understand, it's fairly expensive. It's tough to make a profit on a phone when the battery costs $500. Costs are surely coming down but I think we'll have to wait before it hits the mass markets. From the wikipedia page on graphene [1]: "On the other hand, the price of epitaxial graphene on SiC is dominated by the substrate price, which is approximately $100/cm2 as of 2009." [1] http://en.wikipedia.org/wi…

I would pay $500 extra if I could charge my phone in 1 minute. I would pay $2000 extra if my laptop could do the same.
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