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Electric Car with a 10 minute recharge? Realistic?

Electric Car with a 10 minute recharge? Realistic?

Electric Car with a 10 minute recharge? Realistic?

(OP)
A company called ZAP! (www.zapworld.com) located in Santa Rosa, CA claims it is developing a electric SUV that can be recharged "in as little as 10 minutes". Somehow I find this a bit optimistic.

This got me thinking, and I looked at the specs for an existing state-of-the-art Battery system. The Tesla Roadster battery has the following specs:

Capacity:          56 kWh
Voltage:           375 V (nominal)
Peak Power output: 200 kW (268 HP)
Mass:              450 kg
Recharge time:     3.5 hours

Tesla Motors has a white paper on this that can be found here: http://www.teslamotors.com/display_data/TeslaRoadsterBatterySystem.pdf

To charge the Tesla Battery in 10 minutes would require an power source of about 350 kW. Most folks dont have 3-phase 480 volt service at there house. This is way beyond the capacity available in a typical residence. Though it might be realistic for a corner charging station. I would assume that the ZAP! car would have a even greater power requirement, since its a much larger vehicle (ZAP! doesnt talk about the vehicles mass)

This analysis totally ignores any issues with battery chemistry, themal loading on the battery during charging, etc.

What do you guys think, a 10-minute recharge time for an electric vehicle would be big step towards a practical electric car design.

RE: Electric Car with a 10 minute recharge? Realistic?

I don't see any need for a non-overnight charge for most electric vehicles.

It will always be less efficient.
It will demand larger service.
It would put daytime car charging onto the already stressed national grid, instead of ideal overnight charging.
The connectors will get larger and heavier and more expensive.

I think it's fairly pointless, unless, you are talking about a delivery van, etc.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Electric Car with a 10 minute recharge? Realistic?

Perhaps it all depends what recharged means.  The website also makes the following statements about the Zebra:

http://www.zapworld.com/ZAPWorld.aspx?id=3892
A full charge takes 8 hours.

http://www.zapworld.com/ZAPCMS/uploadedFiles/Charging.pdf
Charge times-Less than 30 minutes (30-80% SOC)  
Less than 2 minutes/mile to charge

Also missing from many discussions on electric vehicles is the impact to the electric system if every house doubles it's typical power consumption.  From a grid perspective, overnight recharging would be better than plugging in at 5pm while you run in to the corner store to get a bite to eat.

RE: Electric Car with a 10 minute recharge? Realistic?

Sounds like simple marketing hype.  "In as little as 10 minutes" seems reasonable if the batteries are at 90% or something.  Misleading, perhaps, but not unusual.

Don Phillips
http://worthingtonengineering.com

RE: Electric Car with a 10 minute recharge? Realistic?

60A circuit at 240V 1 phase. Not unheard of (think Hot Tub).

2 min/mile. So a 10 minute charge will take you 20 miles. Not unheard of for putting around town. They don't claim that you can charge it for an entire day's drive in 10 minutes.

So you go to the grocery store, drop the kids off at soccer, pop down to the barber shop for a trim, pick up the kids after the game and back home. 20 miles total. But you want to take the wife into the city for dinner later and want a full charge for the trip (and make out session on the way home), so you plug in for 10 minutes to top off the power you just used for the errands. Not a bad plan really.

RE: Electric Car with a 10 minute recharge? Realistic?

It's really unusual, unbelievable and never been heard before. Perhaps, it is best suited to salesman sweet pitch voice and advertisement. Technically speaking, it might dump a lot of query and persuasions.




"Whenever you are asked if you can do a job, tell them, certainly I can! Then get busy and find out how to do it." Theodore Roosevelt.

RE: Electric Car with a 10 minute recharge? Realistic?

Suggestion: Install battery bank with quick electrical connectors and hold downs. The service station of the future then will be a battery exchange, where you will change out your depleted batteries for fully charged ones. The batteries will then be slowly charged to be ready for the next day's customer.

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