Electric power: ZENN Motor, which makes this low-speed electric car, plans to use EEStor's energy-storage device for its next vehicles.
ZENN Motor
A startup reports progress on a battery that stores more energy than lithium-ion ones.
A Texas startup says that it has taken a big step toward high-volume production of an ultracapacitor-based energy-storage system that, if claims hold true, would far outperform the best lithium-ion batteries on the market.
Dick Weir, founder and chief executive of EEStor, a startup based in Cedar Park, TX, says that the company has manufactured materials that have met all certification milestones for crystallization, chemical purity, and particle-size consistency. The results suggest that the materials can be made at a high-enough grade to meet the company's performance goals. The company also said a key component of the material can withstand the extreme voltages needed for high energy storage.
"These advancements provide the pathway to meeting our present requirements," Weir says. "This data says we hit the home run."
EEStor claims that its system, called an electrical energy storage unit (EESU), will have more than three times the energy density of the top lithium-ion batteries today. The company also says that the solid-state device will be safer and longer lasting, and will have the ability to recharge in less than five minutes. Toronto-based ZENN Motor, an EEStor investor and customer, says that it's developing an EESU-powered car with a top speed of 80 miles per hour and a 250-mile range. It hopes to launch the vehicle, which the company says will be inexpensive, in the fall of 2009.
But skepticism in the research community is high. At the EESU's core is a ceramic material consisting of a barium titanate powder that is coated with aluminum oxide and a type of glass material. At a materials-research conference earlier this year in San Francisco, it was asked whether such an energy-storage device was possible. "The response was not very positive," said one engineering professor who attended the conference.
Many have questioned EEStor's claims, pointing out that the high voltages needed to approach the targeted energy storage would cause the material to break down and the storage device to short out. There would be little tolerance for impurities or imprecision--something difficult to achieve in a high-volume manufacturing setting, skeptics say.
But Weir is dismissive of such reactions. "EEStor is not hyping," he says. Representatives of the company said in a press release that certification data proves that voltage breakdown of the aluminum oxide occurs at 1,100 volts per micron--nearly three times higher than EEStor's target of 350 volts. "This provides the potential for excellent protection from voltage breakdown," the company said.
Jeff Dahn, a professor of advanced materials in the chemistry and physics departments at Dalhousie University, in Nova Scotia, Canada, says the data suggests that EEStor has developed an "amazingly robust" material. "If you're going to have a one-micron dielectric, it's got to be pretty pure," he says.
A new material prevents overheating, making lithium-ion batteries safer for use in vehicles.
I have been following EEStor for a few years now, and there activities seem very suspicious. Why are they unable to demonstrate a prototype? They clam to be close to mass production, but they can’t create a single device in a lab environment, something is fishy.
I hope their product is real and wish them the best, but I will believe it when I see it.
They've only been in the public eye a few years. Why would anyone open themselves up to being copied or criticized for a product in development. They certainly don't want to lose control by making a public offering of stock.
In my opinion he's handled the whole situation perfectly. Get just the funding you need, prepare for mass production, then come out with a demonstration.
I think a lot of people that claimed to know that EESTor's product wouldn't work will be eating crow soon. You'd think the scientific community would at least have an open mind.
It's not that we don't have an open mind, its that the little bit of technology revealed in the patents and published applications so far appear to be in direct contradiction to known phenomena.
Probably so. It is likely that everything to be known about the physical world is already known and everything that will ever be invented has aleady been invented.
Really?
Why are they moving into EVs first, why not do some proof of principle in smaller electric devices just like A123 did with cordless tools. It does sound suspicious.
I agree.
If their tech works, then why not a little "amazing demo can"? You know, a AA battery sized cap, filled with their stuff, showing 10,000 joule capacity (3x lithium), and say a breakdown voltage of 30 volts.
If P=½CV² ... then 10,000=½CV² then C needs to be 220 FARADS, for that can. Can they do it? That's all I would need to "be a believer". I mean really!!! They've been working on the "research" side for 3+ years. How about a single, cobbled together, compact capacitor having even "the same" energy-capacity per cc as a lithium cap?
To those who say, "they don't want to let the product technology out of the bag", that's just bull. PATENT protection covers their arses there, and well. They just need to show that the actual, practical capacity of their device(s) is about 100x that of today's ultracaps. You can buy a commercial 50F, 17 volt ultracap today that measures about 5cm diameter, and 15 cm length. That corresponds at full charge to 24 J/cc. The lithium ultra-battery stores about 800 J/cc. So, there's the goal. 800 x 3 = 2400 / 24 = 100x!
No demo cap? As far as I'm concerned, then the technology is "pie-in-the-sky", or an ongoing 'technology/science boondoggle' that gets lucrative investment capital, mills out science papers at a tolerably convincing rate, excuses its lack-of-demo devices as premature-because-of-unfinished-safety-research, and keeps going for years, decades.
GoatGuy: I will reserve judgment until Jan. 2010. If they keep delaying year after year I would say their creditability should reach zero by 2015. Why have they done so poorly with the Zenn? The Zenn is nothing like they are promising. Why didn't they wait until they could deliver something closer? I will be watching the next generation Zenn. If it works like they say it will, I will be the first to buy one.
We all wish EEStor well, but it's smelling fishy. This article was back in Aug ... now Feb 09 and counting. People think because some big companies are involved that proves something. Remember those AAA rated mortgage backed securities. Big companies, "experts", big money on the line ... and mud in our face.
Exactly what does EEStor lose by demo'ing? They aim for cars first instead of say laptops or power tools?? Or, energy can be dangerous. If you've got something so good, go for grid storage first rather than consumer apps. I don't get it.
I hope it's true, I hope I'm wrong, but perpetual machines would be really cool too.
First, the dielectric is not intended to be one micron, it is supposed to be about 10.
Second, the breakdown voltage of 1100 v/micron is for the alumina portion. 95% of the dielectric is Barium Titanate, whose breakdown is about 50 v/micron. Funny he doesn't mention that part.
CapacitorMan it would be great to have you join some of the discussions at http://bariumtitanate.blogspot.com/
Although there are a number of people who dismiss scientifically based skepticism there, there are also a number of people with the science as their priority interest.
Thanks CapacitorMan. I've looked into the voltage claim, and it is indeed just the alumina. The article has been changed to make this clear.
After reading the coments of skeptics one thing is obvious - they realy don't have a clue as to what's required and what's not. Their big mistake is their ego - they think they can determine whether the EEStor devices will work by figuring out the architecture, etc. A far better way to estimate probailities is simply to look at those who have seen the device and are convinced that it works (or are at least fairly certain) - such as Lockheed-Martin, the country's largest defense contractor, with thousands of electrical engineers on its payroll, or ZENN Motors, which also has more thn a smattering of what a battery looks like. To believe that the device DOESN'T work, inlight of the confidence shown by these two companies (and CEO Clifford would get sued in a heartbeat by ZENN shareholders if he couldn't produce convincing evidence that his claim that the EESTor devices work was reasonable. The skeptcis are making claims therefore, that are hard to swallow - thet, in essence , are saying that all these folks, who are reputable businessmen and liable for any lies, are in fact, for some strange reason, making claims that the devices work. ZENN is even designing a car specifically for the capacitors. You can perhaps now see the exteme difficulty I have in believing any of the skeptics. None of their explanations can or do explain why their being right makes any sense , given the behavior of the participants.
I think ZENN management should be complete idiots if they would start RnD and made statement about next gen car without any proof for existence of EESTOR device. And I really doubt this :)
Be careful! The skeptics quote 50 year old physics textbooks in support of their skepticism. Also note that the patents talk about composition modified barium titanate, not pure barium titanate. Lastly, the composition modified barium titanate is now reduced into very tiny crystals that may act differently than larger crystals.
The patents that are available for public reading are several years old. Additional patent applications (teens up to about 21 applications) have been filed. These applications are not yet in the public domain.
Actually ... FAITH BELIEVERS are blind. Skeptics either can be simple Missouri "show me" types ("where's the beef?"), or sophisticated Cal/Princeton types ("where's the beef?"). But in any case, until such time as a single TANGIBLE, physical device is demonstrated, all talk about the potential for a new dielectric of superior strength that SHOULD enable storage capacities well in excess of lithium-ion chemical storage ... is just so much research-grant-inducing gas.
Show me a can full of the stuff, with 2 wires, hooked to a volt-meter and a 1 ohm shunt resistor. If it has anywhere near 10+ farads of capacity, in humanly measureable timescales (seconds), I can WRITE DOWN the discharge voltage, and from that determine the capacitance to within a few percent of accuracy. THAT kind of 100-year-old technology, dating to Westinghouse, Tesla, Watt, and Edison **IS** compelling.
Call it "skeptical" if you like, but just show me the device, discharging, hooked to a voltmeter and a IEEE "standard resistor". This isn't even a high-priced demo! Buy it all from scratch, NEW, from an expensive EE supply company, and you're talking what, $150 in parts? Sheesh.
The least a multi-million dollar research firm could do would be to demonstrate this.
The only "problem" is that its also very easy to "cheat the system", by remarking a parts-drawer 10 or 100 ohm resistor to be "1 ohm". The difference is huge ... of course.
Dear Mr. GoatGuy,
Somehow I don't think Dick Weir gives a hoot what you or I think of his claims. Not a hoot.
His is a private company and he owes nothing to anyone except his investors. Some will say that, due to the huge potential benefit that his device could potentially bring to our country and our world, he owes or has a moral obligation to bring to the world an explanation and transparency. I don't personally think he does and I surmise that he doesn't t think so either
"except his investors" Ah, yes. There's the rub. How much due-diligence have they done? Perhaps they are the ones we should be questioning. If I were putting up millions, I would certainly want proof beyond a doubt, but did they get that?
From the purported interview w/ Dick Weir. See http://bariumtitanate.blogspot.com/2008/07/richard-weir-says-permittivity-is.html
Blogger: I hate to bring this up because I feel like I'm pretty clear on the information that's out there in regards to what you're saying about production. But still, alot of people still think that you haven't even got a prototype.
RW: We've have made prototypes of this and those have....they were made with technologies that we had at the time. And what I'm telling the people today is in 2007 we made a corporate decision to put in more advanced technologies which we now and this data shows that we hit a home run on these technologies. Prototypes have been built and prototypes have been tested.
Blogger: tested by 3rd parties?
RW: I'm just going to say that. They've been tested and the data has been reviewed by a lot of people.
I think you make a really good point and I would add that if they were really out to turn a quick buck they would have gone public to raise lots of money on the stock exchange.
Guest (RmW)
Even privately held Cos. must not commit fraud. With Kleiner Perkins and Lockheed looking over their shoulder it is even less likely.
I also find very little solid motive, in all of the releases and blogs, to cause a fraud, so far. Do any of you?
This means, at face value, that the investment risk is primarily scientific and production related. Market risk is small as long as they can ramp up to meet demand.
I believe that if a product was produced by EEStor with even a third of the promised capability - it would be valuable. Maybe less, but still very valuable.
Finally, both ZENN (Who is now making money according to their latest financials) and Lockheed (who nearly prints money) could benefit greatly from a success at EEStor. The downside of an EEStor failure would not be a total loss for either.
You wrote this before the mortgage meltdown and the Madoff fraud. Can you now see how experts can be fooled, big names can lose tons of money on what in hindsight are impossible financial resuls and executives can live life as a fraud??
The error in your assumption is: people are (a) rational, (b) sane. There are many sociopaths who are in business and will lie, scam and cheat for years. There are many people who believe their hopes instead of their eyes. That's why EEStor, Kliener and Lockheed can certainly be just another screw up among many.
I really do hope I'm wrong, but the available facts do not look good. If EEStor does come out with a convincing demo or product, I'll be the first one cheering for a new tool towards clean energy ... but I'm quite skeptical about them right now.
re zenn knowing what they are doing
Recently the company I work for decided to look into providing electric cars for our associates. I contacted Zenn to buy some of their cars. I could not get a coherent response. All they would email me were press releases. In conversations with the City of Vancouver about other green programs I discovered that Vancouver had tried to purchase some of their existing models for a pilot program and that Zenn simply wasn't interested.
Zenn's technical qualities seem to lie in the direction of hyping stock rather than delivering a consumer product.
As for Lockheed Martin a device that does half what is claimed by Eestor, but ends up costing 20,000 dollars or much more each, would be perfectly suitable for many of their applications.
Re: re zenn knowing what they are doing
Reply to arnetwork of 8/5/08 + general info
ZENN is a Canadian company but buying a ZENN car in Canada is not easy, nor has it been legal in most or all of the country. Transport Canada (similar to US DOT) appears to have decided that these low speed vehicles are unsafe on the same public roads with faster vehicles. There is an on-going battle over this issue.
Several weeks ago you couldn't buy a ZENN in any province in Canada. Today I think they are legal in one or more province(s) and other province(s) will commence testing of the vehicles. But, even if legal at this moment, will another shoe drop from Transport Canada in the next week or month?
The current ZENN model uses 6 lead-acid gel cells and is governed to max 25mph. Max range is a couple of dozen miles. In the US, under low speed vehicle laws, it can be operated on streets where the posted speed limit is 35 mph or lower. As opposed to Canada, you can buy and operate these cars in the US in the majority of the states (some states have not subscribed to the low speed vehicle laws).
ZENN has announced that they intend to produce a City ZENN car when they have access to EEStor's capacitor. Target specs are 80mph and over 100 mile range. I strongly suspect that the vehicle, if ever produced, will be produced using a chassis from an established auto manufacturer with EESU and drive system by ZENN. ZENN has also announced intention to produce a 'ZENNergy' (sp?) drive system for purchase by OEMs.
If anyone wants to look, some basic specs for the EEStor EESU were published in a private placement memorandum (roughly equiv to a prospectus for a public offering) issued by ZENN a couple or a few years ago. This doc should be available to all from the sedar.com web site. You might also look at
http://www.rexresearch.com/weir/weir.htm
http://www.technologyreview.com/read_article.aspx?ch=specialsections&sc=batteries&id=20090&a=
http://bariumtitanate.blogspot.com/
http://bariumtitanate.blogspot.com/2008/07/richard-weir-says-permittivity-is.html
, , , and about a dozen other blogs and articles
The intent is to operate the EESU at 3500 volt max charge (5kv for a military or industrial version). The energy stored in a capacitor is proportional to the square of the voltage hence the high voltage targets.
Previous researchers of capacitors using barium titanate dielectrics ran into a problem of saturation of the dielectric at relatively low voltages (well below 3500 or 5000 volts as well as break-thru issues at high voltages. Both of these issues worked to limit the energy storage to a tiny fraction of what EEStor claims for their EESU. Since then, EEStor claims to have advanced the state of he art by using very highly purified BT, composition modified BT (by possibly introducing atoms of other elements into the crystal structure??) reducing domain size and improving polarization and possibly by other methods not presently disclosed.
EEStor is a private company with no obligation to publicly disclose anything to the public.
The reason ZENN has distribution rights to the EEStor EESU for automotive aps is because Ian Clifford saw fit to buy those rights from Dick Weir long before Kleiner Perkins came along. At the time the rights were purchased, gas was cheap and EEStor was far from having a commercial product (and for all we know for sure, might still be) hence a relatively low price for an exclusive distribution right at today's gasoline prices. Since then Kleiner has made an investment and Lockheed also has a relationship, the terms of which are not available to us ordinary citizens. Believe it or not, Kleiner and Lockheed appear to have sent considerable money and lent their good name to a project that pushes the bounds of publically known material capabilities without even having seen a prototype or proof of concept model, just Dick Weir's assurances tht the thing will work. Yes, believe it or not. Your choice.
Re: re zenn knowing what they are doing
"without ever having seen a prototype or proof..."? That would be crazy! How do you know? I can't believe all of the investors could be that stupid. It is more likely that they had to agree to say nothing, including that they had seen proof. Weir seems very secretive. Could it be he sees no benefit in proving anything to non-investors until he has his final product?
Hmmm, let's see. Barium titanate crystals maintain about 5-10% of their peak dielectric constant at 3V per micron, limited by the basic geometry of the crystal. Increase that 367 times to 1100 V per micron and the peak dielectric constant suddenly changes to 200% of it's original value? Gee, I'm going to invest all of my money in Zenn. Teeheeheehahahahohoho.
Re: better than perpetual motion
I did an anagram of your username for more entertainment value than your comment
Bob Gee Ego Ebb
Re: better than perpetual motion
Verbal skills obviously exceed technology comprehension.
Re: better than perpetual motion
eestor claims 350v per micron well bellow saturation
Thickness of dialectric must be wrong
As a matter of fact the article has one point wrong. If Eestor are designing to a breakdown voltage of 350v per micron, then the thickness will be 10 microns, not 1 micron because the published voltage of the Eestor device is 3,500v.
Though still extremely challenging, this means that the purity and grain sizes can be less stringent than a 1 micron separation of electrodes.
Re: Thickness of dialectric must be wrong
I doubt there is a "published" voltage of the EESTOR device at 3.5KV - this is a quiet company in a quiet period - they don't actually have a product to "publish" specs.
I did see the recent release point to initial targets of 350 Volts which was exceeded in testing to 1.1kV
Re: Thickness of dialectric must be wrong
You're right, and the whole discussion is off base yet. There has been no hint of ACTUAL practical working voltages. In the end it DOES NOT MATTER ONE BIT. Why? Because ultimately, the only thing that matters is the joules-per-CC of energy storage for a practical device. If they're low voltage but huge Farads (say "5 volts") then many can be hooked in series to achieve a higher voltage. If they're high voltage, but relatively lower capacitance, then they can be hooked in parallel. If they're between, the BOTH series and parallel. Just basic electronics, that.
But demonstrating even a tiny device that demonstrates an independently observable and calculable energy-product of over 2.5Kj/cc would be fantastic, and would cause this Old Goat to dump some hard-earned money into their stock. The 2.5Kj/cc number is "3 times lithium" (which is about 0.8Kj/cc) - which isn't my, but their claim.
OK, just "show me". I'm game. In fact, I'd become one of the best salesmen-of-stock for this firm, should such a real-world demo, INDEPENDENTLY CHECKED, be done. (it needs that independence because it is all too easy to "cheat" by changing the markings on 'reference resistors' which metrologists use to determine capacitance of test-bed capacitors)
Re: Thickness of dialectric must be wrong
You can't buy their stock, they're a privately held company. That's why they can get away with being so secretive. We have no idea what they've shown their actual investors in private. We can be skeptical if we want, but they simply have no reason to care what any of us think.
Re: Thickness of dialectric must be wrong
The patent clearly says it is a 31F capacitor that is charged to 3,500 volts. See http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=7033406.PN.&OS=PN/7033406&RS=PN/7033406. If this is not published information I do not know what is.
Quantum Tunnelling will deplete the capacitor
I read in a comment elsewhere by a quantum physicist that given the extremely high electrical field (3,500 volts) and the extremely narrow insulation width (10 microns) that quantum tunnelling effects where electrons simply superpose through the insulation will render this capacitor useless.
That is, the capacitor will quickly lose its charge, within minutes or seconds, and the 3,500 volts will drop to something reasonable like 350 volts. As the energy stored is square of the voltage, that means it will lose 99% of its capacity in no time.
Not only EESTOR has not responded to such critiques, but they have not even produced one sample capacitor prototype.
It is notorious how chemists and material scientists are generally ignorant about limiting quantum probabilistic events.
Being an entrepreneur, let me just say that there is a large hype oriented industry that keeps hot stocks afloat to the pleasure of many early investors and promoters.
Guest (RmW)
Re: Quantum Tunnelling will deplete the capacitor
Re no example cap.
You know this because you are an investor. What reason would they have to show us anything at this point in time?
Stock price manipulation? What stock? I'd like to know please inform us.
Biosubs, etc
It is amusing how you can castigate the science based skepticism, but insist on the opposite extreme of blind faith.
Wouldn't any intelligent discussion want to know just how far afield a technology is? Isn't that how science works?
And then there are the conspiracy theorists, and the "Big Oil" concerns.
Amazing, just amazing, and on an MIT base site.
MBT also has a battery that can charge in less than 10 min. The CNT battery is probably the battery that all cars will run in the future.
get the raw data at
http://microbubbletech.com/CNTbattery.html
Ok ok,heh, just havin alittle fun. Figured I would leave a sophistamakated comment, seeins hows this be a MIT thang and all. Basicly just poppin in to say "whatup crackers?".
Well shizzal, I couldn't help myself, I gots to show you my goods, represent. If the deialectric is P= 23567 root of the conductivity squared, then by hyposafees it would seem to corralate that the conductivitee of the matierial would be statik, and likely not produce the needed wattage.(see V+2mS6 x the amprage). Just a thought my quaulity old school G's.
Manufacturing in the United States is in trouble. That's bad news not just for the country's economy but for the future of innovation.
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zakir.ak
6 Comments
need fast charging time
high density battery packs are a boosting field. i think it is in the right direction of future transportations. the main concern is about the time taken to charge the batt-back. last week LOTUS GT introduced it's 700 horse-power Electric Vehicle which charges up in just 10 minutes for a 200 mile run! this will be challenge for all high density automobile battery designers
Reply
dasein
6 Comments
Re: need fast charging time
When they quote a mileage run, say 200 miles, does that mean without a radio, air conditioner or headlights on? If so, what reasonable reduction can you assume with any or all of these items in play?
Reply
DGDanforth
1 Comment
Re: need fast charging time
A short charging time means high current.
One way to achieve this is by discharging a charged EESU into an empty one. But notice that the resultant two EESUs will come to equilibrium holding 1/2 of the original charge in each unit. Hence to have the uncharged EESU come to equilibrium at 350 volts it is necessary for the precharged EESU to be charged at a higher voltage. If we assume there is no loss in energy in the charging process (a false assumption) then we need to equate energy before and after the equilibrium state. If V is the larger voltage of the 'charger' and v is the equalibrium voltage of the two units and noting that the energy in a capacitor with capacitance C is 1/2 C v^2 then we must have
1/2 CV^2 = 1/2 Cv^2 + 1/2 Cv^2
or
V^2 = 2v^2
or
V ~ 1.4v
For v=350 volts we find the 'chargers' voltage must be equal to or greater than
V = 490 volts
As long as that voltage is much smaller than the breakdown voltage of the unit all is well.
I just thought one should realize that the 'home charging unit' must operate at 490 volts in order for the car's unit to operate at 350 volts.
Reply
davack
4 Comments
Re: need fast charging time
Great observation. It is actually voltage that will be high rather than current. Breakdown voltage was demonstrated in the test to be over 1kV.
Reply
rr999999999
3 Comments
Re: need fast charging time
That 630 voltage for houses would be a savings for the home owner. People make a mistake of having just 220 for their home. In the long run they pay more for their electricity.
Reply
GoatGuy
5 Comments
Re: need fast charging time
630 VAC in the home? Are you F***NG nuts? 120 VAC in the US is admittedly low, but pretty darn safe. 220 in "the Continent" and elsewhere is 4x more lethal ... and uses less copper for a given amount of power. Just about at the limit of voltage versus the Common Man. 630? If a single ground-leak were to happen within a kitchen appliance, you'd be fried well before you could jerk your hand/arm/butt away.
Reply
biosubs
12 Comments
Re: need fast charging time
DGDanforth, thank you for the tutorial.
I trust your comments assume that the charging circuit that sits between the two EESUs are simple wires.
Are you aware that when used in the automotive application there is a rather sophisticated "smart" inverter/charger that takes the 3500 volts delivered by the EESU at full charge and reduces it to the voltage needed by the drive motor (probably 200-300 volts AC, probably 3 phase to optimize starting from a dead stop) to do whatever the driver asks of it? This inverter also takes the electrical energy produced during regenerative braking and puts it back into the EESU.
Also, the EESU is actually a ceramic capacitor, not a chemical battery, so charging time is minutes if the charging system can provide the power to do the job quickly. Unlike chemical batteries wherein chemical changes are involved in charging he battery, no chemical changes are involved in the charging of a capacitor. With the proper circuitry interposed between two EESUs, it is possible to top off a capacitor receiving charge at 3000 volts from an EESU operating at well under 3000 volts.
Reply
GoatGuy
5 Comments
Re: need fast charging time
Holy Toledo! Who said anything about 330, or 1000 volts or any other charge-up voltage? Capacitor dielectrics are rated in volts-per-meter (or mm, or micro), but that does NOT imply that a PARTICULAR amount will be in a given capacitor. There is absolutely no hint as to the working voltage of these purported ultra-caps.
The rest of your analysis is essentially correct, but it also loses a different point: that voltage is the integration of current over time divided by capacitance. This is the limit of voltage no matter what. So, the issue really becomes one of "what practical limit on a constant current basis can the ultracaps be charged at?"
Say that an EV has a bank of ultracaps hooked up to hold 100,000,000 joules of energy (at 0.5 Mj/km, equates to 200 km of range), and a rated full-charge voltage of 343 volts (343 = 1.414 x 240, or the peak full-wave-bridge voltage from rectifying a 240 VAC standard service line without transformers. A PRACTICAL goal).
P = ½CV²
100,000,000 = ½ C 343²
C = 1,700 FARADS at 343 volts.
Nominal discharge at 100 km/hr is 50 MJ/hr or 50,000,000 J/hr, or 13,888 J/sec (=watt)
OK, 13,888 watts at the HIGH charge of 343 volts limits out at 40 amps or so. Not alarming. Good actually.
At 50% charge (343 x sqrt(50%) = 240 volts), amps has to go up to 57 amps. And so on. 10% left ... 127 amps.
How big would the constant amps have to be in order to charge the vehicle in 5 minutes?
343 volts
300 sec
= 1.14 volts/sec
V = I/C (for constant I & C)
I = VC = 1.14 x 1700 = 1,933 AMPS.
Almost 2,000 amps? Any idea how BIG the darn cables have to be to carry that without significant resitive power loss? Really big. 12 gauge carries 40 amps safely enough over short distances. So, 50 of those in parallel, with a liquid coolant... One hell of a cable for the common "filling station" to keep fit and sound.
Further ... what if the ultracap "goes critical"? Ever shorted out even a modest sized conventional electrolytic cap? As a fearless kid, I shorted out a 0.022F cap energized at 140 V with a screwdriver. P=½CV² = 0.011 x 140x140 = 200J. Completely destroyed the screwdriver and just about deafened me. Now, let's talk 100 MEGAjoules. That's the explosive power of 24 kilograms of TNT!
THAT, good folks, is something to be concerned about. Because capacitors, "ultra" or conventional, don't have a non-lossy mechanism for slow, safe discharge.
Great idea, but the calcs show the practical problems with the technology. I'm FOR IT, but I don't think the basic claims of "5 minute charge" and "300 km range" are realistic.
GoatGuy
Reply
bigrobhollins
11 Comments
Re: need fast charging time
battery packs might be necessary; but what about this:
you sit in the drivers seat and are confounded by the second handbrake.. you find out that it's the pump for the starting motor. see, you provide the mechanical motion thru which the electrically inert system responds with energy. here's the task list: a high-output electrical motor to power vehicle systesm, an energy reservoir as capacitor, some peak-voltage spark-like design to impell or begin or start the 'car', and that's about it. it could eventually technologically scale itself down to that push-button. it's like how older cars had to be handcranked.. stopping the car would be as easy as turning it off, but, cars may never truly 'stop' again; it'll be like driving a battery that only needs mechanical maintenance and whatnot.
Reply