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  #91  
Old 12-24-2008, 04:37 PM
masalai masalai is offline
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I hope it develops up, and is on the market in 12 months - If it does not leak (internal discharge/decay), I could be interested if same price as AGM's (4 x 220 A @ 60kg each in series for 48vdc) so half the weight and 10 x capacity, if price competitive as a replacement with bonuses....

What about charging (via solar panels &/or i/c engines - - circuits & controllers) and drawing off to electric motors, inverters, and other services....?
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  #92  
Old 12-24-2008, 09:50 PM
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Brian,

If all else fails, read the instructions and use a calculator.
EEstor mention that for road vehicles, the charging stations will be super capacitors themselves, so that the vehicles will be recharged in a time comparable with filling the tank with petrol or diesel. That's quite an infrastructure that will need to be installed. Of course, there will be a greater need for electricity generation, so there is no free lunch. Coal fired powerstations without CO2 capture will do very well, because AGW is a crock and CO2 is not a problem.

Also, as you will be aware, governments tax fuels and they will therefore charge heavily for the recharging of your supercapacitor powered vehicle. Home charging from a plug in your garage is unlikely to figure much in the calculations, because cables would need to be much thicker to handle the load. A 300 mile range requires a lotta kilowatts.

Politicians like Obama (who is so scientifically challenged, he's a one term president), are the problem, He especially, is a marxist disaster for the USA, but Krudd in Ozland is his willing hand maiden and the EU is so corrupt, I predict the global population will fall by five billion by 2050 AD, unless the IPCC policies are scrapped. Welcome to the big freeze. Did you want to live forever?
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  #93  
Old 12-25-2008, 01:07 AM
masalai masalai is offline
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Cryogenic funeral?
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  #94  
Old 12-25-2008, 05:08 AM
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CDK CDK is offline
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The lithium-ion battery used in the Tesla car (www.tesla.com) has a storage capacity of approx. 50 Kw and a weight of 500 kg, which is considered to be state of art. Included within the battery with 6800 cells are 8 microprocessors and a liquid cooling system to keep the battery from turning into a powerful bomb.

The same amount of energy can also be obtained from approx. 6 ltr. of ordinary gasoline....

A newer technology from Stanfort university using silicon nanowires to store the lithium promises a tenfold increase of storage capacity. That would mean 500 Kw. from a 500 kg. battery, comparable to 60 ltr. of gasoline (if all goes well). But this is a very recent development and it will still take several years to set up large scale production.

The super-capacitor is a somewhat different approach that may or may not prove feasible. Because the insulation layer between the electrodes is so thin it is almost virtual, a lot of peripheral equipment, just like that of the Tesla battery will be needed to make it safe for everyday use. It may very well be that at the end of the day it is just as heavy as the Li-ion battery.

About charging.

The efficiency of Li-ion batteries, 85-90% is very good, super-capacitors - in theory - approach 100%. But storing 50 Kw. into a perfect battery still means that you need to pull 50 Kw. from the mains, convert it into the proper voltage (with 10-15% inevitable losses) and feed it to the battery. Any promises that this can be done in the time you need to fill your gas tank are nonsense. Even with 1 hour charging time you would have to draw 500 Amps from your wall socket in the USA or 250 Amps elsewhere. Not realistic!
Using super-capacitor charging stations that keep the 50 Kw in store for you may shorten charging time at enormous expenses but only shift the problem of power demand, not solve it.
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  #95  
Old 12-25-2008, 06:36 AM
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You have to think in terms of the overall system.

Electric motors of moderate rating do not need a gearbox as they give 2 to 3 times rated torque at any point in their speed range. So ditch the gearbox.

An electric motor rated at 50 kW will give the sort of performance of a 150kW IC engine. How much power do you need to cruise continuously at 100kph (the speed limit in most of Australia). So much lighter electric motor than IC.

You can recover all the energy usually lost to brakes. So scale down the brakes they no longer need to dissipate vast amounts of heat.

We are now getting a lighter vehicle. Petrol engine in typical city traffic will achieve 20% efficiency if you are lucky. A good electric set up will get around 80% including motor, controller and battery. That means you need only 1/4 of the initial fuel load to do the same job but everything can be made lighter and you have energy recovery so you get considerably better than 4 times for the same energy on board.

Also ditch the muffler and engine bay sound proofing. Ditch the starter motor and starter battery. Lighten the suspension and chassis as the vehicle has gone on a diet and is now much more nimble.

I read about 10 years ago that if cars had developed at the same pace as computers we would have vehicles that weighed a few kilos and did 1000kph. There is so much invested in current IC technology that it is hard to change but the pieces are coming together. No doubt there are challenges but the basic bits for a revolution are at least feasible. Car makers that sit still will fail.

I believe Formula 1 cars will be permitted to use energy recovery in 2009. Once they start on this slippery slope it won't be long before they go all electric. Batteries/capacitors will be interchangeable like tyres only reused from race to race. The performance potential is staggering compared with existing racers. Improved weight distribution and greater flexibility in layout.

Compare these:
http://www.hobbycity.com/hobbycity/s...ner_(eq:_70-55)
http://www.hobbycity.com/hobbycity/s...ine_CDI_3.13kW
The IC engine is heavier and half the power. This shows what is possible with current state of the art in both fields.

Have a look around at all the model aircraft stuff coming out of China. The vast majority is now electric with lithium batteries. This is where power to weight really counts. They offer staggering performance. They just run. The serious hobbyists carry a couple of batteries and just interchange them but recharge is only 10 minutes or so anyhow - about the same as flying time. No fiddling about trying to get temperamental IC engine to fire.

From what I read we will see all electric cars in quantity in about 3 years and maybe 15 years from now they will be half of all cars produced. Within 50 years I would expect IC to be a collectors item. May be wise to hang onto your current model as they will become a curiosity.

Rick W
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  #96  
Old 12-25-2008, 10:39 AM
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brian eiland brian eiland is offline
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Thinking Positive for the Future

Quote:
Originally Posted by Rick Willoughby View Post
....An electric motor rated at 50 kW will give the sort of performance of a 150kW IC engine. How much power do you need to cruise continuously at 100kph (the speed limit in most of Australia). So much lighter electric motor than IC.

....You can recover all the energy usually lost to brakes. So scale down the brakes they no longer need to dissipate vast amounts of heat.

....We are now getting a lighter vehicle. Petrol engine in typical city traffic will achieve 20% efficiency if you are lucky. A good electric set up will get around 80% including motor, controller and battery. That means you need only 1/4 of the initial fuel load to do the same job but everything can be made lighter and you have energy recovery so you get considerably better than 4 times for the same energy on board.

....From what I read we will see all electric cars in quantity in about 3 years and maybe 15 years from now they will be half of all cars produced. Within 50 years I would expect IC to be a collectors item. May be wise to hang onto your current model as they will become a curiosity.

Rick W
Now that's the kind of positive thinking we need to go forward. Hey, we put a man on the moon in about the same amount of time we have wasted in Iraq!!

WE CAN DO THIS! We should be tasking some of that brain power and money we spend on 'defense contractors' with solving some of these problems. I mean actually make it worth while for these defense contractors to bid on contacts to help develop some of this technology. And this may be particularly applicable in this current economy where speculative funding is in shorter supply.

When you think back about it, I believe you would have to admit that a lot of our miniaturization of electronics, and computerization came about as a result of the space program, and that has filtered down into MANY technologies we have today.

Quote:
Originally Posted by Perciles
Politicians like Obama (who is so scientifically challenged, he's a one term president), are the problem, He especially, is a marxist disaster for the USA
Don't be so hard on this guy....give him a chance. It won't happen overnight as he has a WHOLE LOT of stuff on his plate. But he seems to be able to choose some good people to help him, and hopefully there will be many others that he inspires to help him get the job done.

As saddened as I am about America's image over these past 8 years, I am confident in her overall capabilities. And I am hopeful that this guy Obama will spark a Kennedy feeling in our population

Happy NEW YEAR (certainly the outlook here in Washington is far, far, more positive)
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  #97  
Old 12-25-2008, 11:09 AM
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Quote:
Originally Posted by brian eiland View Post
........
As saddened as I am about America's image over these past 8 years, I am confident in her overall capabilities. And I am hopeful that this guy Obama will spark a Kennedy feeling in our population

Happy NEW YEAR (certainly the outlook here in Washington is far, far, more positive)
As an outsider I see George dubya as a nice guy on a tough gig. He is able to laugh at himself and seems to make lasting friendships. Would be simply regarded as a nice guy in an easier job.

He has had a massive tilt at freeing the world of misfits determined to hurt others. Hopefully this will become a positive legacy that we will remember his administration for.

I guess there are plenty of negatives that come to mind but I think many of these were set in train much longer ago than 8 years. The mounting debt (OK fighting wars doesn't help), the love affair with fuel guzzlers, the fascination with guns and the destruction they cause, the oppressive airport security and many other oppressive laws that threaten personal freedom etc

I also think that US is now at the forefront of alternative energy if you consider quantity produced rather than by proportion to total energy. Certainly there is a lot of good stuff available there that is not produced elsewhere yet.

Rick W
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  #98  
Old 12-26-2008, 07:12 PM
colinstone colinstone is offline
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The new BMW Mini electric has a 150kw motor - which seems to be completely OTT on the basis that a 50kw elec is equiv to 150kw IC. Doesn't get much range from a back seat load of battery despite brake regeneration. Until elec can get the energy density up, it cannot compete. Hydrogen is more like it, but getting the H is the problem.
I saw a bit of kit in USA on a James May BBC TV programme - "in the deserts of New Mexico, James seeks out some modern-day alchemists, who offer the promise of allowing him to drive his car on petrol conjured out of thin air". Takes sunlight, water and CO2 to produce petrol and oxygen. Each unit, 2.5m dish to catch the sunlight, was producing 3 - 4 litres petrol per day.
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  #99  
Old 12-26-2008, 09:56 PM
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JonathanCole JonathanCole is offline
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Battery fundamentals

Quote:
Originally Posted by brian eiland View Post
Now that's the kind of positive thinking we need to go forward.
Actually positive thinking helps, but a bit of practical engineering would be helpful too. Most electric vehicles proposed are using high voltage batteries made up of small voltage cells (up to 3 volts DC) in series to attain the high voltage. People who work with batteries find out certain fundamental truths. For instance, the battery made of series connected cells is no better than the weakest of them. If one cell has a significantly higher internal resistance than the others, it will heat up an hasten the failure of the whole pack.This is bound to happen in a battery pack made of 100 or more individual cells (such as in the Chevy Volt). Then how do you identify the weak cell and can it be replaced or do you have to replace the whole pack?

Most battery manufacturers say that you should not mix new cells with old as the older weaker cell will reduce te capacity of the new cell. That suggests to me that we need to develop higher voltage cells (such as EEStor) or utilize DC to DC converters to attain the necessary voltages. Interestingly, in a vehicle, the distances between battery and driven components is not far, so the issue of wire size is not critical until you get to the components themselves. There is no fundamental reason I know of why batteries should not be relatively low voltage devices and there are lots of advantages such as safety and heat dissipation. High frequency, DC to DC conversion is very efficient and robust.

If vehicle manufacturers start building electric vehicles that are prone to catastrophic failure because they have not taken the fundamentals into account, we are really up the creek without a paddle, because then all the naysayers will be jumping up and down, gleefully rubbing their hands together as they say, "See, I told you it could never work!!"
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  #100  
Old 12-28-2008, 09:44 AM
FAST FRED FAST FRED is offline
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"Politicians like Obama (who is so scientifically challenged, he's a one term president), are the problem,"

Politicos are all mostly lawyers , none can think outside self aggrandizement.

A real hassle for govs will be taxing to get the same cash as now.

NO gov budget ever gets cut , just cuts in "projected " growth levels.

Our burning up food to use of alcohol reduces the mileage about by the alcohol content , so 10% of the fuel purchase price is unused for propulsion. But farmers and ADM have huge lobbys.

Many years ago we reduced exhaust emissions by "better" and cleaner burning engines.

That is far in the past and we now pay about 15% in less efficient engines , to appease the "Global Warming" false religion.

The combination adds to about 25% of the govs tax extractions are simply , as usual, the combination of FORCE and FRAUD .

Electric cars may be nice for the Global Warming believers , but will probably be very deer for us users.

But at least we may stop burning the worlds food supply!

FF
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  #101  
Old 12-28-2008, 07:21 PM
eponodyne eponodyne is offline
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Quote:
Originally Posted by Pericles View Post
Brian,

If all else fails, read the instructions and use a calculator.
EEstor mention that for road vehicles, the charging stations will be super capacitors themselves, so that the vehicles will be recharged in a time comparable with filling the tank with petrol or diesel. That's quite an infrastructure that will need to be installed. Of course, there will be a greater need for electricity generation, so there is no free lunch. Coal fired powerstations without CO2 capture will do very well, because AGW is a crock and CO2 is not a problem.

Also, as you will be aware, governments tax fuels and they will therefore charge heavily for the recharging of your supercapacitor powered vehicle. Home charging from a plug in your garage is unlikely to figure much in the calculations, because cables would need to be much thicker to handle the load. A 300 mile range requires a lotta kilowatts.

Politicians like Obama (who is so scientifically challenged, he's a one term president), are the problem, He especially, is a marxist disaster for the USA, but Krudd in Ozland is his willing hand maiden and the EU is so corrupt, I predict the global population will fall by five billion by 2050 AD, unless the IPCC policies are scrapped. Welcome to the big freeze. Did you want to live forever?

When you look in the mirror, do you ever stop and think, "I am just completely and totally full of ****?"

Because if you don't you should.
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  #102  
Old 12-29-2008, 01:54 AM
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Pericles Pericles is offline
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eponodyne,

You took five days to put your cogent and lucid reply together and you had to swear and you even blaspheme with your signature, not that I actually am concerned about that kind of thing! I would however, appreciate knowing to which paragraph you are objecting.

BTW, punctuation is the politesse of princes. It's "Because comma if you don't comma you should exclamation mark" Not wot U rote!
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  #103  
Old 12-30-2008, 02:49 AM
eponodyne eponodyne is offline
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To what do I refer? Well, all the erroneous facts, the dearly-held notions cherished as actual facts, and the abyssal depths of your lack of compassion for the world around you. Just for starters.

Now I also am going to object to your shock at the blasphemation in my sig: I'm an atheist. Jesus, if he ever existed, was a semi-literate carpenter, had some good ideas, and had a whole cult spring up around him. I don't buy into it... but you can have whatever invisible friend you want if it makes you happy to do so; it's no skin off my ass.

"Marxist disaster." Ohhh, my ribs. That's a good one.

In re the attempt at correcting my grammar, I must of course defer to your superior knowledge of the mother tongue. Mind that you speak English while I speak American. Part of what you object to with my usage of comma could probably be chalked up to regional dialectical variation, if one is willing to accept the concept of the Intertubes as a "region."
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  #104  
Old 12-30-2008, 03:40 AM
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Pericles Pericles is offline
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eponodyne,

Good man. I did say I wasn't concerned about your Yeshua bar Jusif comment and I do so, for the same reason.
http://www.positiveatheism.org/hist/quotes/qframe.htm

Compassion for the entire world however, is a pointless exercise. The opposite of love is not hate. Both are emotions and as such, are part of the same coin. Indifference is the opposite of love and/or compassion. Indifference is helpful, because if we humans were constantly moved by all the shocking events that occur worldwide, naught would get done. Not feeling every pain is how we survive. As a moot point, recession is when your neighbour loses his job, depression is when you lose your job.

As for grammar and punctuation, it just requires some study and an open mind. Don't be handicapped by your supposition that speaking American lets you off continuing to learn. Rectify yourself and enjoy the warm fuzzy feeling of a task well done.

OTOH, do not get bogged down with this. "English pronunciation is divided into two main accent groups, the rhotic (pronounced /ˈroʊtɪk/) and non-rhotic, depending on when the sound typically represented in spelling with the letter R is pronounced." http://en.wikipedia.org/wiki/Nonrhotic

Hell's teeth. That's even more than I want to know.

Good grief. There's more. Let me out of here. http://en.wikipedia.org/wiki/Southern_English_English
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  #105  
Old 12-30-2008, 06:48 AM
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CDK CDK is offline
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What are you up to, guys?
This post is about storing energy, electro-chemical processes, innovation, not about accusing each other of stupidity, religion or qualifications for a man elected by the US people to pull them out of the swamp.

Pericles, your user name suggests wisdom, so resist the temptation to respond to caustic off-topic posts.
We are all entitled to our religions or the lack of one, and we all have opinions about politics. But we must hide both in technical discussions because they cannot possibly make a sensible contribution. If we continue following this path, we may end up quoting Donald Duck to prove our point.

I agree with you that the language on this forum is sometimes maltreated to the point where it hurts the eye, especially by authors in English speaking regions of this planet. But that tells us something about their level of education and helps in rating their opinions. Let it be!
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