Why battery-powered aircraft will never have significant range

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Dan Thomas

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Sep 17, 2008
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6,032
Battery teck is close to bieng viable for some
aviation aplications.......Currently batteryies are improving at about 5%
per year,or more over the last 10 years.
At 5% per year, you get a 63% improvement over ten years. And we're looking for orders of magnitude in battery improvements? You know what an order of magnitude is? It's ten times more, not 0.63 times more. We need an order of magnitude so that the range is much better than an ICE airplane, since we really don't want to fly for a couple of hours and them wait the rest of the day for the thing to recharge. A ten-hour range would solve that.

Math and physics are SO inconvenient. Reality hurts.

I'm not against electric vehicles. Really. ICE are dirty and noisy and inefficient and their vibrations destroy stuff. I should know, I am a retired aircraft maintenance engineer (Canadian). And a pilot and former flight instructor.

But electric airplanes are a long ways from being practical and affordable. It will take a lot of time, or some breakthrough technology, to advance them much more. Besides that, what will happen when the environmental activists wake up to the devastation caused by mining the special stuff needed for these motors and batteries? It'll get really expensive, that's what.

We can rattle on and on about what's happening in the electric world. That sort of talk has been going on a long time already and we've seen incremental advances, not a breakthrough. I will remind you that the lithium ion battery was invented 54 years ago. The nickel-cadmium battery was invented 130 years ago. Development is not that rapid.
 

dog

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Joined
Dec 29, 2019
Messages
557
Actually ICE does still have plenty of room for improvement, they've just been complacent because they had a highly profitable business with little competition. Opposed piston engines are one interesting category for further R&D. And there's a company called Alfadan that's working on a new 4 cylinder inline with higher displacement than has been possible thus far, due to a dynamic balancing issue caused by asymmetry of the up and down strokes of the cylinders with simple connecting rods to the crankshaft. The youtube channel "driving 4 answers" has a good video on it.

On the electric side, there's an interesting company called FreeLTech which has achieved 7.5kWh/kg and 62kW/kg, and may be able to reach 20kWh/kg. Sounds too good to be true, but they're probably not lying. Though we'll probably never see it either, because the physical mechanism that it's based on has been independently discovered many times over the past 100 years and every time it gets buried again. They call it "charge clusters", but everyone who discovers it gives it a new name. Ball lightning is the naturally occurring version.
Nuhuh,buddy ol pal fren O mine.
ICE has one and only one possibility.
And that is a material sciences breakthrough
that yields something that is able to be very
very strong at refractory temperatures,alowing for compression ratios of 50/1 or 100/1 ,and
the sudsequent expansion of the combustion
gasses to atmospheric (or close) pressures
and a near doubling of overall efficiency.
And hey ya opposed piston diesels like the ones they ran in the dornier flying boats,good
stuff.
Ball lightning,canned heat,charge clusters!,
oh oh,where did that little red dot come from
 

dog

Well-Known Member
Joined
Dec 29, 2019
Messages
557
At 5% per year, you get a 63% improvement over ten years. And we're looking for orders of magnitude in battery improvements? You know what an order of magnitude is? It's ten times more, not 0.63 times more. We need an order of magnitude so that the range is much better than an ICE airplane, since we really don't want to fly for a couple of hours and them wait the rest of the day for the thing to recharge. A ten-hour range would solve that.

Math and physics are SO inconvenient. Reality hurts.

I'm not against electric vehicles. Really. ICE are dirty and noisy and inefficient and their vibrations destroy stuff. I should know, I am a retired aircraft maintenance engineer (Canadian). And a pilot and former flight instructor.

But electric airplanes are a long ways from being practical and affordable. It will take a lot of time, or some breakthrough technology, to advance them much more. Besides that, what will happen when the environmental activists wake up to the devastation caused by mining the special stuff needed for these motors and batteries? It'll get really expensive, that's what.

We can rattle on and on about what's happening in the electric world. That sort of talk has been going on a long time already and we've seen incremental advances, not a breakthrough. I will remind you that the lithium ion battery was invented 54 years ago. The nickel-cadmium battery was invented 130 years ago. Development is not that rapid.
So ya,you know your stuff,all aspects of current conventional aviation down to a tee.Wish that my project was further along and that you lived on the right coast so that I could directly benifit from that experiance as I can use any help I can get.
This thread used the word never in relation to
electric aviation,and I am having fun 1 taking exception to that and 2 learning more about battery and related tech and the whole revolution in research and development happening right now.
And hold up here,NEVER,as used in the context
of this thread is the polar opposite of perpetual
motion, and should be just as taboo.
Anyhow at work now,building an off grid solar
pv system to power a shop that will be used to
further my aviation related ambitions amongst
things.
 

Victor Bravo

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KWHP, Los Angeles CA, USA
My friend and local EAA chapter president Charlie is famous for trying to make a big thunderous blanket statement at the end of each and every discussion about cost or efficiency in light personal airplanes... "The future is electric!!!"

So, being the official smart-ass of our chapter (and perhaps this chapter too) I always chime in say "yeah, the distant future".

We're both probably right. Whenever they do come up with a better energy storage solution, we'll have some sort of bolt-on STC for our 172's and Bonanzas. That time will come, as the time has eventually come for manned space flight, carbon fiber, the telephone, and running water.

Electricity and batteries is already the world standard energy storage solution for our phones and our cameras. It's close, but not quite here as the best solution for our cars, but that will be here at some point.

For now, electric power is indeed a different energy storage solution for airplanes and air travel, but it's not the best solution.

I would buy an electric motorglider today if I had the means.
 

Victor Bravo

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KWHP, Los Angeles CA, USA
New-age light weight and ultra-light weight high performance gliders. The earlier generations of gliders were very heavy. Better materials and better construction methods could cut this weight down significantly, allowing a smaller glider to fly with almost equal performance as the older larger gliders. Certainly the ability to fly in "lighter air". There is probably enough raw materials in an old SZD-42 Jantar to build two or perhaps three smaller and lighter gliders with almost the same performance as the big old Open Jantar.
 

Daleandee

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Location
SC
And there's a company called Alfadan that's working on a new 4 cylinder inline with higher displacement than has been possible thus far, due to a dynamic balancing issue caused by asymmetry of the up and down strokes of the cylinders with simple connecting rods to the crankshaft.
I was scouring the net and found that video and then your post referencing the video and their redesign of the connecting rod. No one knows yet where they are going but many believe they are designing a variable pivot at the wrist pin end of the rod. Some diesel manufacturers have been working in this direction for sometime and also working on variable compression. If what they claim is true (and they have some clout on their side) the amount of power from small engines may be increased substantially. But it remains to be seen how this all flushes out ...
 

Sockmonkey

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Joined
Apr 24, 2014
Messages
2,247
Location
Flint, Mi, USA
You can get the same advantage with a scotch yoke if you do it right, but the patent on that ran out so it wouldn't be proprietary.
 

Daleandee

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Joined
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Messages
1,430
Location
SC
You can get the same advantage with a scotch yoke if you do it right, but the patent on that ran out so it wouldn't be proprietary.
Some commenters I've seen on the web seem to think they are heading in a direction similar to this:

1623035649173.png

But at this point it's anyone's guess ...
 

Saville

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Joined
Apr 28, 2014
Messages
175
Location
Boston Ma
And yet another issue to be dealt with if battery driven dreams come to fruition [emphasis mine]:


"The battery pack of a Tesla Model S is a feat of intricate engineering. .......But when the battery comes to the end of its life, its green benefits fade. If it ends up in a landfill, its cells can release problematic toxins, including heavy metals. And recycling the battery can be a hazardous business, warns materials scientist Dana Thompson of the University of Leicester. Cut too deep into a Tesla cell, or in the wrong place, and it can short-circuit, combust, and release toxic fumes.

That’s just one of the many problems confronting researchers, including Thompson, who are trying to tackle an emerging problem: how to recycle the millions of electric vehicle (EV) batteries that manufacturers expect to produce over the next few decades. Current EV batteries “are really not designed to be recycled,” says Thompson, a research fellow at the Faraday Institution, a research center focused on battery issues in the United Kingdom.

That wasn’t much of a problem when EVs were rare. But now the technology is taking off. Several carmakers have said they plan to phase out combustion engines within a few decades, and industry analysts predict at least 145 million EVs will be on the road by 2030, up from just 11 million last year. “People are starting to realize this is an issue,” Thompson says."

 

Dusan

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Location
Canada
Cut too deep into a Tesla cell, or in the wrong place, and it can short-circuit, combust, and release toxic fumes
As opposed to ICE that are releasing toxic fumes all the time - while operating.

Joking aside, the batteries can last for the whole car life, Tesla is demonstrating this, but even when at the end of useful automotive life, the batteries can be refurbished for other energy storage. Eventually recycling makes lots of sense, especially containing expensive - hard to find materials.
 

Aesquire

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Rochester, NY, USA
That's theoretically true. Although the term "Useful Automotive Life" is absolute marketing pig feces. Is there a nicer way to describe lying? "refurbished for other energy storage" is another term that has a very limited truth content.

There are Youtube videos where people are playing with junked batteries, and I admire the cleverness of getting a great deal on batteries that are burned down to a fraction of the design capacity. If weight is irrelevant, and cost is almost free, a stack of old Prius NiCads would be very nifty to run the house when the power goes out. ( as it does at my house several times a year, mostly during high wind and blizzard days )

I'm not sure if "used hybrid/EV batteries from the junk yard" is going to be a viable source for amateurs very long. I remember when "diesel from waste cooking grease ( in my shed at home )" was a popular idea, that has faded as the producers of the grease ( everyone who does fried food ) transitioned from "we have to pay to have the foul stuff trucked off to the rendering plant, so why not let the crazy guy take it away" to "the rendering plant pays for the waste, so get lost weirdo". There were both economic, and regulatory issues involved there, and there will be with old batteries.

And we'll have to develop the technology to recycle all those toxic waste filled battery packs. On a mass commercial scale. Lead is nasty until the planet vaporizes, sure, but it doesn't burn your garage down. And it might be NIMBY of me, but I'm going to object if you pile them up, and set them on fire to reclaim the melted metals from the ashes. Like is done today in some countries. ( insert here rant on Dictatorships that have little care for human life that isn't their Own Clan/Party/Cult )

And modern car engines are pretty darn clean. Not perfectly, of course, you can still seal up your garage and commit suicide by sitting in a running car until you pass from CO poisoning. OTOH my 2009 VW diesel had exhaust cleaner than the air in Los Angeles on a mediocre day if I told the computer it was being tested for emissions. Better than a typical Beijing summer otherwise. Still wouldn't sit in a vault with it running. So, toxic fumes? Yeah, some. If alcohol burning external combustion ( turbines, steam engines ) is substituted, you'd lose a tiny amount of oxides of Nitrogen, and a bunch of CO. Still have the larger picture pollution issues that electric, fossil fuels, and every other human effort has.

TANSTAAFL.
 

Dusan

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Canada
Although the term "Useful Automotive Life" is absolute marketing pig feces.
This is not marketing - it's my own opinion based on my own experience of driving the 8.5 years old tesla model S I own. It has about 7% battery degradation accumulated over the years, so I expect it will still work 5 years from now. Why do you think I'm lying? I'm just presenting facts from my own experience. I tend to take offence over this kind of comments, but for now I'm considering this just a misunderstanding.

As for re-purposing batteries, I have recovered good cells from EOL laptop batteries and use those for very nice led lightning around the house and garden. They are working for years now with a custom made charger that don't try to squeeze every bit of performance as the laptop's original one.

There is very little lead into the current lithium batteries, but there is definitely more in the 'low lead' 100LL avgas and by burning it - all that nasty lead goes up into the air to be inhaled eventually. There is a reason the TEL was banned from the automotive industry years ago.
 
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