Charging during a long drive

Charging during a long drive

I love Model S and I cannot wait to own one. All I have is one practical question:

live in Boston Area and drive to New York City/Southern New Jersey few times a year. Each way is about 270 driving distance. So will there be any charging facilities en-route I-95 or I-84, and how long will it take to charge at my brother's place in New Jersey from a standard at home 110V electric outlet.

Kevin Sharpe | 14. februar 2011

The Roadster at 110V can take 30+ hours to charge, so if you have the 300 mile Model S you are looking at several days.

Invest in a 240V >40A outlet at your brothers place and you'll get the recharge time down to something more manageable.

Vawlkus | 15. februar 2011

If a DC fast charge stop pops up along your route, that'll be a fast way to get charge as well.

Check with google maps and see if they've got word of a charging station going in along your route. They're trying to keep abreast of that as best as they can.

Samuel H. | 15. februar 2011

I have a question. Why do batteries degrade when fast-charged?

Anyway, electric cars with long ranges will not be very successful. Their long charging times would be prohibitive. Shorter range EVs are the future because of their shorter charging times. If a 600 mile range electric car were introduced, the charging time from empty to full would be formidable, even with a 240V charger.

The Model S is perfect. When I take road trips, we never drive for more than two and a half hours without a stop. Stretching legs, using the bathroom, dining and resting are essential to a great road trip. During all of those times, the car can be charging. Having a "short" range is a good incentive to stop and take a needed rest. Otherwise, we might unwisely choose not to stop.

Road trips are not about just getting there. It's the experience. Stopping often, helps us experience different places, rather than just passing through. If you want to get somewhere far away quickly, take a plane!

Timo | 15. februar 2011

"Shorter range EVs are the future because of their shorter charging times. If a 600 mile range electric car were introduced, the charging time from empty to full would be formidable, even with a 240V charger."

That doesn't make sense. It would take just as long for smaller pack to charge for 600 miles than 600 mile pack, or other way around, it takes just as little time for 600 mile pack to charge for 300 mile worth as 300 mile pack (actually 600 mile pack takes a bit less time in both cases).

William13 | 15. februar 2011

Thanks Timo. The fastest.charge time is from 10 or 20% to 80 or 90%. Cetainly a 600 mile pack is more desirable. If you go 500 miles on one trip it is no big deal to spend the next few nights catching up on the charge. I do not fill up my ICE with gasoline every day and thus have a less than 350 mile range.

William13 | 15. februar 2011

I will be investigating business opportunities for fast charging stations along my common routes at either toll rest stops or Starbuck or similar 45 minute spots. Currently everyone fills up completely, but I expect with more options people may only spend 15 to 30 minutes to top off. This will not be economically viable for a few years, but Internet advertising of locations and 5 year loss plans could pay off well in the long run. The investment should run about $100,000 per station. My biggest concern is damage and theft during the first years before they become profitable. There would be no need for any actual human monitoring except as routine for maintenance. Nearby cameras could be used to deter damage and theft. Once I get my Model S I will be investigating this further.

Vawlkus | 16. februar 2011

The major reason fast charging is bad for batteries is the thermal build during charging.

Think about it, you're forcefeeding those batteries 80 to 90% of their capacity in less than 30 mins. That much power moving through wires and into batteries creates a LOT of heat (electronic/electrical system efficiencies aren't at 100%, so there's always some power loss which manifests as heat).

Model S has a temperature management system but I don't know how effective it is if it has to deal with fast charging on a regular basis. I'd like to think that Tesla's engineers have made allowance for the heat fast charging is going to generate, but until the car is built and on the road, there's no real way to know for sure.

msiano17 | 16. februar 2011

Hey everyone here's a quick link about what Chicago is supposedly doing to help promote EV and charging stations

A nice thing Tesla could do would be to have a power cable and adapter that can turn a 110v to 220v ... I am a bit ignorant on the technical and engineering challenges that an idea like that may incur, so correct me if that is not a plausible conception.

If it were though, simple fix for long trips. Plug into any outlet turn on converter and shorten up charge time.

VolkerP | 17. februar 2011


sorry to correct that - it will not work. the device you just imagined is called a transformator. It transforms AC from input to output voltage in a fixed ratio. The drawback is, currents will be transformed the opposite ratio. Remember, electric power equals current multiplied with voltage. The physical laws of energy conservation demand that input power equals output power here. So if you convert 110V to 220V, but are limited to draw 10 Amps on the 110V socket, the charger will receive 220V but will be limited to 5 Amps. Otherwise it will blow the fuse on the 110V socket.

Fast charging an EV is about drawing high power, not high voltage or high currents. Given the same voltage, more amps is better than fewer amps. Given the same amp (e.g. limited by the wiring) more voltage is better than fewer volts.


msiano17 | 17. februar 2011


Thanks for the correction. Very well explained on the concept. Best thing we can hope for is the article I posted to be true and more and more cities/towns/private investors to buy into the phase 3 chargers for a good quick charge.

qwk | 18. februar 2011


Actually it is possible as long as you use two different 110 outlets on different breakers. This will require an extension cord(proper spec).

It has already been done before to charge a roadster. Google is your friend.