| Author | Message | ||
     Gregtonn |
http://www.greenprophet.com/2013/03/supercapacitor -graphene-maher-el-kady-breakthrough-ucl/ I helped develop a "super capacitor" for the Space Station some thought to be a huge advancement. I think this is Epic The problem with batteries is charge time. If you can store energy in near real time it changes everything. G | ||
| Hootowl |
1.5 kilometers of surface area per gram! Holy crap! Interestingly enough, the UPS that supplied backup power to the avionics test bench I used to work on was powered entirely by capacitors. The UPS was bigger than the bench. | ||
| Reepicheep |
That's particularly cool because it seems much more towards the "doable" end of the vaporware spectrum. The news article butchers the physics really badly, but the details are tough for a layman to understand, and the article has the right theme. A super capacitor that has high energy density and very low leakage (self discharge) would create a revolution in technology... provided we will move to safe nuclear power to feed it. | ||
| Hootowl |
Capacitors charge much more rapidly than batteries. Perhaps they could be used in regenerative braking systems. They don't have to store power for very long. How difficult would it be to insert an electric motor in the powertrain of a rear wheel drive delivery truck? You could mate it to the drive shaft, perhaps with an electric clutch and a toothed belt. Such a system could easily be retrofitted to existing vehicles too. | ||
| Reepicheep |
I've thought that exact same thing Hoot, to the point of trying to figure out a brake disk and caliper electric drivetrain retrofit for electric or even compressed air that only claims regenerative braking losses. I was picturing a retrofit rotor and caliper that was half smooth traditional disk brake and half geared electric motor. It would be limited in terms of short term power storage, but it would be potentially simpler. And braking losses are the big difference between city MPG and highway MPG, which is like 30%. Never could come up with an approach that sounded better then art major fantasy concept videos though.  | ||
| Hootowl |
I'm picturing a pulley attached to the drive shaft near the output shaft of the transmission. That drives a pulley connected to the motor through a simple electric clutch like those used on automotive AC compressors. Brake on = motor spinning and charging capacitors. Gas on = capacitors discharge through the motor. After the stored power is exhausted, the clutch engages (disengages? I never was clear about that ) and disconnects the motor from the drive shaft. Pretty simple affair. | ||
| Reepicheep |
That would be easy. Tie it into the brake lights, so the "I'm braking" signal is already there as well. I wonder if compressed air and an air motor would be more or less cost and loss efficient than electric... | ||
| Hootowl |
Electric might be quieter, and potentially more compact and require less maintenance. But yeah, people are already doing hybrid compressed air stuff. | ||
| Pikeben08 |
I used to work on a hydraulic hybrid version of the concept for garbage trucks. Cost was much less than electric. Returned about a 15% FE improvement if memory serves correctly. Hydraulics and supercaps are similar in behavior, low energy high power. Great for vehicles that stop and go a lot. | ||
| Hootowl |
I'm curious how hydraulic pressure was stored. Was the energy ultimately store as compressed air above the hydraulic fluid? Can't appreciably compress a fluid (that's why hydraulics work ) so it has to be air or something, right? | ||
| Pikeben08 |
Yes, compressed nitrogen bladders. | ||
| Reepicheep |
Liquid nitrogen generators? | ||
| Sifo |
Not meaning to downplay this, but from what I gather from that article, they are no where near the capacity needed for a vehicle. Is there real hope of getting to that stage? Even if not viable for vehicle, I can see where it would be great for a lot of things. Charging a phone in a matter of seconds? Or cordless tools? It can be a game changer for many modern wunderstuffs. | ||
| Pikeben08 |
"Liquid nitrogen generators?" Yes we used the temperature difference to power a stirling engine to move the vehicle.  | ||
| Tq_freak |
Pikeben08 - Did you work for Parker Hannifin? I did some work on a similar hydraulic hybrid UPS truck. | ||
| Pikeben08 |
No, I used to work for Bosch. Parker was one of our main competitors. | ||
| Mr_grumpy |
What with, new supercapacitors & sugar/enzyme batteries, we'll be saying goodbye to the i-c engine soon. It just won't be as visceral an experience as having multiple controlled explosions going on between your legs. | ||
| Hootowl |
Eat more cabbage and beans | ||
| Aesquire |
I've been watching this tech for years now. Someday, they will have an actual product for sale, and I hope it comes close to the efficiencies that the imaginary one has. All new tech is hyped by the press, partly because the inventor understands that the press does NOT understand qualifications. If you are honest, you say "this new thing, if it works in the real world like this tiny model works in the lab, could be a great replacement for the old stuff. Assuming we can scale it up and that we can make it for less than solid perfect diamonds the size of a house, which is our current cost structure. But we're pretty sure we can solve the 7 different obstacles to practicality, and hope there won't be too many more that make this not work." So, knowing that won't even get printed, you say "this new thing will eventually replace the old stuff and is so much better it's freaking awesome". THAT get's printed. The other reason it get's hyped is it's going to take millions of dollars to build the factory and build the new machines to make the new stuff and actually get it to market. Nothing you buy will be made on an old CD burner. So...... you have to get investors interested. That said, I have high hopes for graphene/graphite supercapacitors. http://www.extremetech.com/extreme/175137-sugar-po wered-biobattery-has-10-times-the-energy-storage-o f-lithium-your-smartphone-might-soon-run-on-enzyme s My bet is the supercapacitor will be commercial before the sugar battery, but you can buy alcohol micro batteries to charge your phone now, so I could be wrong. Now if we could just capture the hot air from our capitol...... (Message edited by aesquire on February 06, 2014) | ||
| Panhead_dan |
ICE power may be replaced by another system as the norm but it will never go away. Like rock and roll, it's here to stay. http://www.youtube.com/watch?v=j0kJdrfzjAg | ||
| Thumper74 |
Hoot, on road racing cars, they have a pinion driven pump on the rear differential that pumps the gear oil to an external cooler. What if you ran the generator off a similar setup that was actuated via an electric clutch like an AC compressor? | ||
| Aesquire |
Great. http://www.youtube.com/watch?v=g266Uwp6ZnI http://www.youtube.com/watch?v=AXSvSXz18K4 | ||
| Gregtonn |
"Change is essential for progress. Without change there can be no progress." G | ||
| Brumbear |
If this thing is real and I have to believe it is. The world is fixin to change. The uses are enormous, put one in every home and use unconventional ways to keep it charged ie wind turbine/solar. Automotive, public transportation, the uses are mind boggling!!!!!!!!! | ||
| Sifo |
I'm unclear how this is going to work for any reasonable transportation. They compare a Lithium Ion battery to an equal size capacitor of this type and the Lithium Ion battery stores 12.5 times as much energy. Size and weight are two of the big factors limiting Lithium Ion in vehicles right now. Requiring a battery 12.5 times larger isn't going to leave room for a driver. I have no idea how weight or cost will compare. It's interesting tech, but I'm not seeing this as being all that great for a lot of common applications. Fast charge times are great, but if it means that your phone is the size of a large brick again, we have just gone gone backwards 30 years. | ||
| Rick_a |
Every concept has a start somewhere, I guess. With enough time and money thrown at it, it could become something with some viability. | ||
| Sifo |
Every concept has a start somewhere, I guess. No doubt, and the capacitor started here...  After many decades it is becoming something much, much better, but far less than commonly available battery technology. It's impressive as a capacitor, but sounds like it may not compete well with batteries. Of course, it's possible that they are greatly underselling what they are working on in the laboratory, but that seldom works out to be the case. Reality tends to be a bitch! | ||
| Reepicheep |
It could be useful in two pretty important ways... The first and most obvious is regenerative braking. That really is most of the magic in a hybrid car, and it probably accounts for 30% wasting of fuel any time you are doing something other than steady state cruising on an open interstate. If all you want is regenerative braking, you don't need to store a *lot* of power. All you need is enough to accelerate the car from 0 to 100 mph one time. You need a ton of space for LiIon to be able to go 50 miles on just electric. This isn't that, the electric only needs to go one mile. So 1/50th the capacity. So a pure regenerative braking solution would be an easy win. Secondly, lots of battery technologies can store energy pretty well, but suffer in terms of efficiency or lifespan when you discharge them quickly. So in this case, you could make longer living more efficient batteries if you use them to slowly charge one of these super capacitors (again on that is just big enough for a single 0 to 100mph burst), and the capacitor then feeds the electric motor peak demands. Picture a small stream, filling a pond slowly, and the pond can open the floodgates once every hour. That was my thinking anyway. | ||
| Pikeben08 |
http://www.technologyreview.com/news/415773/next-s top-ultracapacitor-buses/ On another note, Reduced brake wear and downtime costs also help offset the cost of hybrid bus/garbage truck applications. | ||
| Sifo |
I see, and understand what you are saying about regenerative brakes. It makes a lot of sense. I think the braking system will get somewhat more complicated though. I think you will need computer controlled systems to keep a linear feel to them. BTW, I've seen mileage on our school buses as low as 4.5 miles to the gallon in this cold weather and snow. I would estimate our bus depot drives more than 7,000 miles per day. Anything that bumps the mileage is a good thing. I just don't see it as a panecea. |
