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The Replacement For the Battery?
Posted by
kdawson
on Tue Jan 23, 2007 07:14 PM
from the charge-it dept.
from the charge-it dept.
jackd writes "Great article in Technology Review, bordering on 'too good to be true,' about a small company in Texas that is developing the replacement for the electrochemical battery. The device is a kind of hybrid battery-ultracapacitor based on barium-titanate powders. Quoting: 'The company boldly claims that its system... will dramatically outperform the best lithium-ion batteries on the market in terms of energy density, price, charge time, and safety... The implications are enormous and, for many, unbelievable. Such a breakthrough has the potential to radically transform a transportation sector already flirting with an electric renaissance.'"
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Why are they even trying to do cars? (Score:5, Insightful)
Re: (Score:3, Insightful)
Because companies like Honda and Ford won't produce a viable electric car on their own!
Re:Why are they even trying to do cars? (Score:5, Funny)
Ok, this will sound like conspiracy theory stuff, but is it not interesting that a small company in *Texas* just happens to announce a 10- to 20-fold imrovement on battery technology - and emphasises cars more than they ought to - just when an embattled prez is preparing to announce new domestic energy policies, and is widely blamed for foreign policies that are driving up oil prices?
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Re: (Score:3, Insightful)
my car battery is cheap, lasts longer than 5 years and just works.
My laptop battery however is a piece of expensive useless junk.
Fix broken things not things that are already fixed.
Re:Why are they even trying to do cars? (Score:5, Informative)
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Re:Why are they even trying to do cars? (Score:5, Funny)
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Miracles Required? (Score:5, Insightful)
http://digitalcrusader.ca/archives/2006/09/power_
http://digitalcrusader.ca/archives/2007/01/ultrac
And I remain unconvinced that they are going to actually achieve what they claim. And even if they did, we don't have the 10,000amp service at my house necessary to actually charge them at speed. And we haven't heard anything about "leakage" (or "self-discharge") rates.
It's all vapor ware until they show us a functioning prototype instead of just bragging about materials purity...
Re:Miracles Required? (Score:5, Insightful)
And even if they did, we don't have the 10,000amp service at my house necessary to actually charge them at speed.
I'm skeptical as well, but your argument above is silly. I don't have a refinery or a pumping station at my house, yet my car is quite practical.
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Re: (Score:3, Funny)
filling a gas tank and charging a battery are surprisingly different propositions.
So are filling a tank with gas compared with getting a bag of feed for the horse.
Re:Miracles Required? (Score:4, Insightful)
From there, you've got to ask yourself what the environmental impact of building these things is, what the impact of disposing of them is, and whether the change is going to make a means of transportation that is better than or worse than what already exists.
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Re:Miracles Required? (Score:5, Insightful)
TFA states the energy storage of the battery was 15 KWH. Therefore to charge it in 10 minutes would require 90 KW or 375 Amp service at 240 Volts. Now this would be a lot of current for a household circuit but totally within reason for a "filling station". A typical household application (30 Amps at 240 Volts) would be able to charge the battery in 2hrs 5min.
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Re:Miracles Required? (Score:4, Interesting)
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About fast charging... (Score:5, Informative)
It's when you're on a long trip and you need to refill and go that you'll be wishing for a filling station with an ultracap-compatible, high-power electrical supply---for which you'd likely be willing to pay a premium kWh rate.
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Re:About fast charging... (Score:5, Insightful)
The same concept applies at the gas station- just have a big bank of capacitors. On the other hand, this type of power is perfectly doable if you have a high voltage line going to the gas station. I think people forget how much juice is going through those things, thousands of times more than what gets to your house.
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Re:About fast charging... (Score:4, Informative)
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Color me (Score:5, Insightful)
I'm tired of "too good to be true" products whose primary goal is to draw VC.
I hope they last long (Score:5, Interesting)
So far, the supercaps i know of are quite expensive, and their performance degrades - i.e. with each charge cycle, the capacity gets smaller and smaller. I am not sure what the lifespan of a supercapacitor is, but it surely isn't terrbily long. I guess for the current applications (flash in cameras for example) its not all that critical - how many times is flash used over the lifetime of the camera.. If the lifespan is really improved, then they may be onto something.
Re:I hope they last long (Score:4, Funny)
>> whats next.. ubercapacitors? ubersuperultracapacitors..
googlecapacitors!
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Re:I hope they last long (Score:5, Funny)
I for one welcome our new googlecapacitor overlords.
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Googol = 10^100 (Score:4, Informative)
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I was pretty sure... (Score:3, Funny)
Capacitor
SuperCapacitor
Capacitor64
Capacitor^3
Gii
Some people will claim anything to get investors.. (Score:4, Insightful)
Pound for pound. (Score:4, Funny)
10 amp-hour 12V Li-Ion Battery: 500 grams ($100).
versus
10 amp-hour 12V Ultracapacitor (or 36-amp-second 12kV ultracapacitor): 50 grams ($100).
Current-limiting resistor of sufficient wattage rating to ensure that ultracapacitor storing that much energy won't vaporize any conductor that it happens to touch...: 450g. ($Priceless)
I don't know about you but... (Score:5, Funny)
Re:I don't know about you but... (Score:5, Funny)
I've been insulated from this kind of humor all my life, and frankly, it made me want to bolt. I'm trying to resist, but my capacity for remaining grounded has charged off over the horizon, transforming me from a person who inducts current events into their personality to one who follows an entirely different arc.
Parent
Seems unlikely (Score:4, Insightful)
Per the article,
So, let's see...lead-acid batteries have a energy density of 30-50 Wh/Kg. Lithium-ion is 110-160 Wh/Kg. If it packs 10x as much as lead-acid batteries we can expect an energy density of 300-500 Wh/Kh. About 3-4x that of li-ion battery. Although the claim doesn't seem overly outrageous I find it unlikely that someone has managed this sort of improvement while the rest of the world is clueless.
The article is confusing (Score:3, Informative)
Re: (Score:3, Interesting)
so they're claiming more like 2 1/3 an Li-ion battery. On the other hand even if the thing is too fragile and doesn't have enough temperature range for over-the-road use as some anticipate, I can think of some useful thing to do with it in a stationary mode such as peak buffering
Dupe (Score:5, Informative)
Good news, bad news... (Score:5, Funny)
The bad news: it's Sony.
Re:Good news, bad news... (Score:4, Funny)
The news is still good
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Don't Try This At Home (Score:4, Interesting)
Oh man.. as if tossing a charged capacitor to an unsuspecting victim wasn't funny enough already.
Re: (Score:3, Insightful)
I just don't get this danger angle. I mean, yes, charged high-voltage capacitors can be dangerous. So can bottles of gasoline with flaming pieces of cloth stuffed in the neck. And yet, none of us seems to be particularly freaked out by a fifteen-gallon can of gasoline strapped under our butts when we're driving---even with thousands of tiny explosions occurring per minute under the hood in front of us.
I'm not sa
Re: (Score:3, Funny)
Phillip Jose Farmers Riverworld series had this. (Score:4, Interesting)
I can't really understand Jim Miller's criticism (Score:4, Informative)
"We're skeptical, number one, because of leakage," says Miller, explaining that high-voltage ultracaps have a tendency to self-discharge quickly. "Meaning, if you leave it parked overnight it will discharge, and you'll have to charge it back up in the morning."
The Jim Miller quote above confuses me, as Maxwell Technologies advertises a 125V output power module which is spec'd to only lose 70% of its charge after 30 days. So why is he contradicting his own company's products?
For those who are unfamiliar, while ultracaps sound fantastic, they are ultimately bound by the physical laws of capacitors, one law being that their output voltage drops (linearly) as they discharge. Maxwell Technologies knows about this, so they develop ultracapacitor arrays with extremely high internal voltages (4000+ V) and regulate the power output using efficient step-down converters. Battery cells, of course, do this naturally, because the electrochemical reactions generating the current do so at a voltage determined by the electric potential of the galvanic reaction inside the cell.
This is one reason why you don't hear much about using ultracaps in portable electronic equipment. While ultracaps may be relatively compact, they are still bulky, and though they may be able to provide the necessary voltage, you have to factor in doubling or even tripling the required voltage to use efficient step-down converters. The story gets even worse for charging. Let's say you want to charge using 12 volts DC. Do you run through dedicated charging circuitry which takes in "safe" voltage, but can only charge the ultracap at battery-style rates (low current), or do you try and charge the ultracap in its theoretical minimum charge time (high current), which means that the wall-warts you are used to seeing will look more like big, boxy IGBT/Invert-based welders (and you thought your xbox 360 power supply was big...)
In short, while it sounds good in theory, the practical challenges of discharging and charging ultracaps are fairly sizable.
Clarifying my post... (Score:4, Interesting)
> Get the losses down where those Maxwell caps are and you lose 15 miles per day to losses.
Since the power loss is not constant, which was the whole point, obviously this part has to be taken in the context of the next (fairly mangled) sentence and assume nightly recharging to 100% to enable the 500 mile advertised range. Which would be the logical course, so an unexpected trip could be undertaken without worrying about charging.
> Large losses mean splitting it into banks and only charging what you plan on needing plus a reserve.
Doh. The obvious method is of course to leave it one big bank and only recharge it to give tomorrow's driving plus a fudge factor if self discharge is a problem. (Explanation left as exercise)
But running the numbers a little more gets some disturbing trends. Assume the loss is only equal to 15 miles of driving per day as I did in the best case above. That means every single car would be wasting enough power to drive a NYC to LA round trip annually. But keep the caps around 25% charge most days would cut the waste in half. Assuming that the real world loss curve looks close to a perfect capacitor discharge.
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Kleiner Perkins is funding this (Score:4, Interesting)
First off, this was reported in Business Week back in 2005 [businessweek.com], with some of the same quotes.
What's striking is that Kleiner Perkins, one of Silicon Valley's top venture capital firms, is funding this. If they're funding it, it's not totally bogus; they will have done a due diligence and had some competent people look over the technology. There may turn out to be some reason it's not feasible, but if it was physically impossible, they wouldn't have obtained money from that group.
Is this more wishful hype than physics? (Score:3, Informative)
This is hundres of times more than polystyrene, but the challeng is still formidable:
A cap with 320Wh/kg or 1GJ/m^3 or 1kJ/cm^3 at 3kV would require:
C/cm^3=0.7Farad
Since C=k*e0*A/d, e0=8.8E-12, k=5000
we get C(BaTiO3)/cm^3=4.4E-8*A/d
and with A*d=1cm^3 (not all of the cap can be dielectric so this is a ceiling)we get:
A=4m^2 and d=250nm
So with d=250nm, and U=3kV, the voltage across the dielectric is 12GV/m. Breakdown voltage for most ceramics are less than 300MV/m.
This would imply less than 1% the capacity claimed. Still an incredible feat, but the car would only go a few km.
About 10 or 15 years back.../usage model (Score:3, Interesting)
Perhaps the same could be used here. Pull into a "gas station". Dump & replace t
Redox flow batteries (Score:4, Informative)
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Re: (Score:3, Informative)
Um, you mean like the recently announced Chevy Volt (made by GM, the "company that killed the electric car"), which has a 40 km capacity on battery, and a small elec
Re: (Score:3, Insightful)
Yeah, then all we'd need is this shit called "energy."
KFG
Re:Can I buy stock in this company? (Score:5, Funny)
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Hate to break it to you: (Score:5, Informative)
From TFA:
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Re:Fantastic! Until... (Score:5, Insightful)
Actually, no, what I have written is crazy. I forgot to take into account that these are the same people that suppressed the 400 mile to the gallon carburettor and had the guy killed that invented the car that only runs on water.
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Re: (Score:3, Interesting)
Watts per kilogram (330) and Watts per cubic centimeter (not derivable from speculations).
Then I'll be impressed.
(a 25g AA battery at 1.2v output would store 6875 mAh, assuming a similar density to NiMH. Half of that would impress me.)
Another Slashdot "Investment Opportunity"? (Score:5, Informative)
"Unfortunately EEStor never made and will never make the supercapacitor described in the patent [google.com] because they ignore a well known physical effect, called "dielectric saturation".
"Barium titanate has been used in capacitors for decades, due to its high dielectric constant: (PDF file) [avxcorp.com].
"However, the dielectric constant drops as the electric field strength increases: http://www.nap.edu/books/NI000488/html/49.html [nap.edu]
http://prola.aps.org/abstract/PR/v71/i12/p890_1 [aps.org]
"At a hypothetical field of 3500 Volts over a thickness of 12.76 micrometers, as proposed in the patent, the dielectric constant of barium titanate would be orders of magnitude lower than the claimed 18500, reducing capacity and energy density by the same factor...
"This has been discussed in more detail by Prof. Anatoly Moskalev on December 24th and 26th, 2006 in
http://www.teslamotors.com/blog1/index.php?p=43 [teslamotors.com]
"with an update on January 20th, 2007:
http://www.teslamotors.com/blog1/?p=46 [teslamotors.com]."
Also read this comment considerably below:
"Further evidences of EEstor's hype! by Roger Pham 1/22/2007 10:41 PM
"In his patent #7033406, Richard Weir, EEstor CEO, cited data published WAY BACK in 1985 from the Japan's Journal of Applied Physics, as basis for the high dielectric property of Barium Titanate (BaTiO3)powder, when coated with aluminum oxide and calcium magnesium aluminosilicated glass. If BaTiO3 capacitor was so good way back in the 1985, the likes of the GM EV1 would be around evey street corners since 1996, or the Prius would have been a PHEV way back in 1997!
"What held back coated BaTiO3 powder from becoming a SuperCapacitor was the fact that BaTiO3 has dielectric property that varies by nearly ten folds with just typical seasonal swing in ambient temperature, and the fact that its dielectric property drops by as much with high electrical field strength, as Emosson has brought up!"
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Re: (Score:3, Informative)
For example, your television steps your house current up to a couple thousand volts. At, say, 120kv, your house circuit need only handle 20A (ie: 120kv by 0.02A is 20A at 120v. Given the specs of 280Wh/kg and 100lb [45.5kg] for a vehicle power system, that means we have 12kWh to fill. That means 5 hours for a complete fill-up, or just leaving your car plugged in overnight.)
Re:Charged in 10 minutes (Score:5, Insightful)
Not lines; a line. Proabably with a nice idiot-proof interconnect (so there's never any bare conductor). You could probably do it with a low-voltage/high-current magnetic coupling (also designed to not be 'on' until coupled).
"You would also have to have a transformer to upconvert from street voltage to 120KV, those are expensive."
Never heard of a flyback? If not, I don't suggest disassembling your TV. Anyways, they can be had for tens of dollars, or built for less (if you have LOTS of time on your hands)
"Just because you increase the voltage to offset the current flow, it will not negate the fact that you are sending 12KW through, you need big wires for that."
You're not sending 12KW through; you're sending 12 kWh through, over the course of five to eight hours. That means your cable has to be rated for 1500-2400W, 12.5-20A@120V at the transformer input, 0.0125-0.02A@12kV at the output.
Knowing a little Ohm's Law might help you out. Or at least knowing the difference between a Watt and a Watt-Hour.
Meanwhile, the voltage step up has nothing to do with 'offsetting' the current. Because of the way ultracaps work, you have to fill them using a very high potential difference (or suffer a greatly reduced operating capacity). You then step the voltage back down in the device using it (one of the reasons I don't see this tech in small applications anytime soon).
Anyway, a 20A/120V line is about 3/8" in diameter, insulator included (you generally see them as the bright orange extension cables). Hell, your air conditioner has thicker than you'd need (they're usually rated for 30A@120V). Truth is, current determines conductor size, so at 0.02A the conductor need not be very thick - though you'd want to bring it back up to the 3/8" diameter using insulator so as to protect from the voltage; I imagine 12kV would hurt a bit.
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