Author Topic: This could be interesting.. (Read 773 times)

John Hammonds · « **on:** March 09, 2013, 04:17:39 PM »

Super capacitors

TTFN
John.

Dennis Adamisin · « **Reply #1 on:** March 09, 2013, 04:31:39 PM »

What we have is GOOD but it is only going to keep getting better...

Bob Hunt · « **Reply #2 on:** March 09, 2013, 04:51:01 PM »

Or, as I like to say, "Today is the worst that electric flight will ever be!" In my mind it's far superior to any other type of propulsion, and it will just keep getting better day by day (almost hour by hour...). This is the train I want to be on that's leaving the station...

Bob Hunt

Crist Rigotti · « **Reply #3 on:** March 09, 2013, 05:01:01 PM »

I don't think this is a good idea. How will we ever get our models to balance if we didn't have that overweight, expensive battery to help us out? Yep, this type of thing would defiantly be step backward for us electric flyer's.

Bob Hudak · « **Reply #4 on:** March 09, 2013, 07:04:57 PM »

Wow ! Finally, the break thru we've been waiting for. Welcome to the future.

Tim Wescott · « **Reply #5 on:** March 09, 2013, 08:36:13 PM »

For the past 15 or 20 years, every couple of years some astonishing new breakthrough in electrical power storage -- often some variety of supercap, but just as often a new battery technology -- gets announced with much fanfare and hoopla. Then reality sets in, and it turns out that the technology is a lab queen that can't survive the rigors of the everyday world, or has to be hand-assembled by gnomes, or something.

So I'm skeptical. Not disbelieving -- LiPo batteries were part of that crowd until they distinguished themselves by actually working as promised -- but I'm not going to put off buying my next set of batteries, either.

Capacitive energy storage would put interesting constraints on the electronics, because while battery voltage does drop a bit as the energy is depleted, capacitors drop voltage a lot: at 50% depletion the voltage is about 70% of the starting value, at 75% depletion the voltage is at 50%, at 90% depletion the voltage is down to 30% of the starting value.

So it's good to keep your eye on it, but don't get too excited yet.

Mark Scarborough · « **Reply #6 on:** March 09, 2013, 08:42:22 PM »

Quote from: Tim Wescott on March 09, 2013, 08:36:13 PM

For the past 15 or 20 years, every couple of years some astonishing new breakthrough in electrical power storage -- often some variety of supercap, but just as often a new battery technology -- gets announced with much fanfare and hoopla. Then reality sets in, and it turns out that the technology is a lab queen that can't survive the rigors of the everyday world, or has to be hand-assembled by gnomes, or something.

So I'm skeptical. Not disbelieving -- LiPo batteries were part of that crowd until they distinguished themselves by actually working as promised -- but I'm not going to put off buying my next set of batteries, either.

Capacitive energy storage would put interesting constraints on the electronics, because while battery voltage does drop a bit as the energy is depleted, capacitors drop voltage a lot: at 50% depletion the voltage is about 70% of the starting value, at 75% depletion the voltage is at 50%, at 90% depletion the voltage is down to 30% of the starting value.

So it's good to keep your eye on it, but don't get too excited yet.

spoilsport,, ya just had to bring reality into it didnt ya,, sheesh,, some peoples kids,,,

Bob Hunt · « **Reply #7 on:** March 09, 2013, 08:49:35 PM »

Daydream shattered!

We still have the wafer batteries to look forward to; and they are a reality I'm told...

Thanks a lot, Tim...

Bob Hunt

phil c · « **Reply #8 on:** March 10, 2013, 09:55:23 PM »

I certainly hope one of these technologies comes to fruition. We need energy storage with twice the kWh of lipos to be really competitive with fuels. Energy density is almost everything.

I've been playing around with electric for combat, as have a few other people. It's possible to be competitive in performance, but only for flights of 90 seconds or so. A conventional electric setup works OK for slow combat, but at a weight penalty of 4 ounces or so on a 19 oz. airframe.

Larry Renger · « **Reply #9 on:** March 21, 2013, 12:01:01 AM »

As far as I can tell, electric is totally competitive until you get down to small models (.06 and smaller). I have flown a .15 size RSM P-51 electric to a 500+ point pattern as judged by a couple of top CLPA pilots. That is better than I have ever done with "wet" power.

It is only when you want to fly true 1/2 A (under 200 sq.in.) models that you really are at a disadvantage.

As do we all, I await the coming new technologies. With progress, the battery improvements will only continue to advance the quality of electric power. I suspect that without room temperature superconductors, motor performance is pretty much "there". I would be delighted to be wrong!

Actually, for the small models, the wires and connectors are a serious size, bulk and weight burden!