Filed under: EV/Plug-in, AutoblogGreen Exclusive
ABG Reader Question: What does it take to charge a battery in 10 minutes?
We regularly get questions from readers asking for more detail or clarifications on the topics we write about. This morning Andrea wrote in with this question:
I was wondering if you could help me out. I was reading about this new car, the Lighting, that uses NanoSafe batteries you talked about in one of your posts. They say that in order to charge it's nanosafe batteries you only need 10 minutes. Is it only 10 minutes of normal electricity (the one we have at home)? Are they saying that you plug your batteries into a normal home outlet for 10 minutes and you are done or there's something I am missing?
The answer to this question is an unequivocal NO! You can plug in the Altairnano (or A123) batteries into a 110V outlet to charge but that takes 6-8 hours for a full charge. The fast charging capability requires a special charging station that no one is likely to have at home any time in the foreseeable future.
When ABG interviewed Altairnano CEO Dr. Alan Gotcher earlier this year he explained what was needed. The fast charging requires 480V and somewhere between 500-1000 amps. They foresee gas stations and the like installing charge stations that would store electricity locally in something like a huge capacitor and then pump it into the car on demand. This kind of station won't be cheap, requires a huge cable to charge the battery at that rate and poses potential safety risks. When I spoke to Ric Fulop of A123 last week, he explained that their batteries are capable of such fast charging as well, but they aren't advertising it or focusing on it because of the infrastructure that would be needed to support it. So even though Phoenix, Zap, Lightning and Altairnano are talking up that capability, don't expect anyone, except perhaps some fleet operators, to be able to do this.
Reader Comments (Page 1 of 1)
kballs 11:00PM (8/17/2007)
Sam is right, that is huge power dissipation and is a bit dangerous for your average untrained person... they have such systems at airports to charge electric forklift and tow equipment and such, but you'll never have one at home.
On the other hand, most homes DO have 220v 60amp, which can charge your A123 batteries about 8x faster than 110v 15amp... so instead of 8 hours you could theoretically do it in 1 hour.
That said, most of the time you can charge overnight and not worry about it... and you're probably not going to need 100% charge every time, only a partial charge, so that speeds it up even more. If it has gas/diesel range extending, then it's even less of an issue.
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ug 11:09PM (8/17/2007)
I think the way to do this is for a gas station to be able to charge only one car at a time and have it roll into a modified robotic carwash system. You'd have to get out of the car. The charger cable would plug in robotically. If people primarily rely on overnight chargers I think having to get in line for an emergency charge won't be too bad. It would be like waiting for a slow drive-through meal.
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Dave 11:12PM (8/17/2007)
Even 10 minutes is probably too long.
In less time, you could remove and replace a bettery pack in an appropriately designed electric.
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Fabio 3:33AM (8/18/2007)
Yes, replacing the batteries sounds like a much better approch, provided there'd be some kind of battery format standardization. That would also let carmakers loan the batteries at a symbolic price rather than sell them, lowering the initial cost of the cars.
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Scatter 5:02AM (8/18/2007)
For anyone who wants to work the time to charge out for themselves...
Power(kW) = [Voltage(V) x Current(A)]/1000
Time(h) = Power(kW) / Battery Capacity(kWh)
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Fabio 5:24AM (8/18/2007)
Scatter,
Shouldn't it rather be
Time(h) = Battery Capacity(kWh) / Power(kW)
? ;-)
Or rather:
UsefulPower(kW) = Power(kW) - Power absorbed by home utilities (kW)
Time(h) = Battery Capacity(kWh) / UsefulPower(kW)
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Scatter 7:23AM (8/18/2007)
aahahhahahah. yes it should be. oooops! thanks Fabio!!! First post of the morning and my brain wasn't quite in gear hehe.
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rgseidl 8:25AM (8/18/2007)
Batteries are electrochemical reactors and, chemistry takes time. This is why they cannot deliver the power density of hydrocarbon fuels powering ICEs.
However, car makers want to minimize their investment risk by insisting that alternate drivetrain technologies deliver the same or better acceleration, speed, comfort, range and refill/recharge times as ICEs do. Their assumption is that consumers simply will not buy something that is inferior in any of these respects.
This may also be why California's ZEV mandate includes an alternate compliance option that heavily favors vehicles with long range and fast refill capability. For a long time, that meant FCVs not BEVs.
For a second car used primarily for commuting and running local errands, limited range and all-night recharge times do not actually represent serious limitations on utility. The question is, can/will families shell out major $$$ for a second car, no matter how quiet or cheap to run it is?
How much are zero tailpipe emissions and improved national energy security worth to the average Joe Schmoe - as opposed to Silicon Valley techno-geeks and Hollywood publicity hounds? These are contributions to the common good and, no-one wants to be the sucker that lets their neighbors get a free ride.
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Tony Belding 1:14PM (8/18/2007)
"The question is, can/will families shell out major $$$ for a second car, no matter how quiet or cheap to run it is?" -- rgseidl
I imagine they will when gasoline costs $8/gallon, if you are lucky enough to find any available where you live, and if you have a ration ticket allowing you to buy some. That's where we just might be heading within the next 10 years.
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rgseidl 5:05PM (8/18/2007)
@ Tony Belding -
I'm a big fan of raising US gas taxes and at the same time, cutting income and/or general sales taxes. Nothing would put more urgency behind new fuel-efficient models.
However, given the politics of the US, people would rather their grandchildren pay for overseas wars to protect their own profligate lifestyle today. So $8 gasoline in the US is unlikely to happen in the next 10 years. Maybe in 25, when there are more cars in China than in all the rest of the world combined.
Btw, some Europeans are already paying $7/gallon and there is no continent-wide clamor for electric vehicles just yet.
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Tony Belding 7:15PM (8/18/2007)
Given the projected trends I've seen for global oil production and demand, I don't think any amount of foreign wars are going to make any difference -- particularly if you factor in the oil consumption of our military. We haven't exactly opened up a huge spigot of oil in Iraq, despite our best efforts, while our military is still burning through fuel (and ammo, and money, and soldiers) like crazy.
If I had to guesstimate, I'd project $8/gal around 2014.
As for Europe. . . There are two reasons why they haven't gone to EVs on a large scale yet. First, gasoline may be expensive there, but it reflects taxes rather than actual shortages. It may be expensive, but they don't face any prospects of rationing or long lines at the pumps -- those would be huge motivators. Secondly, EV technology is still developing. It's not quite ready yet, but it's developing rapidly.
At some point the trends of decreasing fuel availability and improving battery technology will cross. I don't know when the "tipping point" will occur in the marketplace, but it's coming.
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Paul 12:34PM (8/19/2007)
The third and most obvious reason for European acquiescence to higher gas prices is the simple fact that car ownership and gas usage there is simply much more "discretionary" than here in the US. Population density and availability of public transportation there makes car usage much less of a necessity. It is far less often that you find folks commuting 30+ miles to work daily there than you do here. In the US, cuts in energy usage will likely also require some urban re-engineering to go along with changes in individual vehicular consumption, but that will take time (and a reality check on the part of the government and the people that the free market won't solve everything in a timely enough fashion to deal with the growing energy crisis).
I'm not convinced of the viability of a battery replacement system. I think that kballs is more on in that 95% of car usage will be served quite well by "slow" charging. We'll only need the 10 minute quick charge for extended trips, and then, only a small percentage of current gas stations will require retrofit to support the high voltage charging stations. Since home (and perhaps work) slow charging will be relatively easily facilitated without major infrastructure changes, ALTI batteries (or others with such fast charging capabilities) are probably fine as a relatively near-term solution.
Longer term, batteries not requiring lithium might be required due to potential (and real) shortages, but that will come.
Politics aside, I'm very much against a flat tax increase for fuel for a number of reasons, not the least of which being that it will cause a major pain in our economy without (in my opinion-shared by many others) making a major dent in consumption (again because such a big part of our consumption here in the US is simply not discretionary). I'd much rather see better carrots and sticks geared to decrease purchases of large vehicles among consumers and increase R&D for better consumption (including of course battery tech) among manufacturers.
No doubt the government should step in, but tax increases are not a silver bullet and would likely cause more pain than they could possibly offset by changing consumption habits.
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Chris M 10:59PM (8/22/2007)
10 minute charging became a big issue when the CARB board gave favored status to "zero emission vehicles" that could be refueled in 10 minutes or less as a way to favor H2 fuel cells over batteries. Hmm, seems to have backfired...
I'm not convinced that "10 minute" charging is really necessary. After driving 140 to 200 miles, I'm ready to stop, take a break, stretch a bit, have a snack or maybe lunch - taked about 45 minutes to an hour. If there were some charge stations in the parking lot of the diner, I could plug in, swipe my charge card, go get a bite to eat, use the restroom, then be on my way with a 1 hour charge.
Technically speaking, it would be much easier and much cheaper to do a 1 hour charge than a 10 minute charge. Only 1/6th as much power required!
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GreenGuy 3:58PM (9/11/2007)
On the ZAP website on the product slick for the Xebra sedan in the lower right corner there is a picture of the fast charger http://www.zapworld.com/files/zap-docs/xebra-slick.pdf
I am fortunate enough to live by the ZAP! HQ showroom and saw it there for a while. It is probably just under 6 feet and was on wheels to be easily moved around. I did not get a close look but it definitely seemed like it could placed in any persons garage and take up barely any space.
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