# Forums

## Charging voltage

Hello everyone,

As Tesla intend to sell cars world wide I just would like to check how versatile the charging is designed.

In north America I understand you get one phase 110V 60 Hz or 220 V for larger appliances. Here in Europe we have 3 phase, 400V, 50 Hz and typically 50 A into the houses, for older systems slightly different systems are installed. Also, you always have 1 phase, 230 V, 50 Hz with 10, 13, 15 or 16 A fuses.

For an efficient charging, you want to use as much power as you can for your car. The more power, the shorter charging duration is needed. With 3 phase, 400V, 50 A can charge the car fully in 45 minutes but your single phase, 230V and 10 A may need 10 hours.

Does anyone know how Tesla S is solving this?

Jaffray | November 8, 2010

@ok, check out the charging options on this site...the HPC units are capable of charging throughput up to 70 amps which equates to a little less than a 4 hour charge.

Timo | November 8, 2010

That's with the specially made charger. There is no info about European three-phase connector possibility anywhere, probably because Roadster can't use that.

There just is no info about European standard connectors at all.

I asked to include those in FAQ-section, but nothing has happened. It just says that "Model S plugs into any standard 110 volt or 220 volt outlet. No additional “infrastructure” is needed." That's US voltages. AFAIK US 220V is three-phase, so apparently it can use three-phase too, but there is no mention about European 400V systems, which connectors etc.

Jaffray | November 8, 2010

@ Timo, what are European Roadster owners using to charge then?...is their only option the Mobile connector with the array of different pigtails?

Timo | November 9, 2010

Probably that specially made charger or mobile connectors for standard wall outlet. Note that European usual three-phase is more powerful than that specially made charger. IIRC charger has 500V@70A = 35kW (DC I think), while standard three phase has at least 400@3x35A = 42kW if the house is not tiny. 3x50A is not uncommon.

I'm not sure Roadster onboard charger can handle that. OTOH when you have 230V coming out from standard wall outlet you pretty much don't need those chargers. Single-phase 3+kW is good enough to top off Roadster for usual small commuting during night.

This is all of course just guesswork, because this site has no info about European charging standards. Maybe some European Roadster owner has more info.

Jakob | November 9, 2010

usually here in eurpoe you find single phase plugs 10A, 220V, that's 2.2 kW. if you're really looking for you can find three phase plugs with 10A, 400V.
3phase 35A, 400V is what we have for an average household!!
if you want to increase from 35A to 70A fro the household to have these 35A for your tesla U'll have to pay some thousand for the main fuse to the electricity company for network usage.
for this reason in europe it would be smarter having the small battery, charging every night with only 1 Phase 10A and having a range extender for weekly/monthly longer trips.
If tesla wont offer this opportunity people will buy electric cars, that can do this (see opel ampera for example)
(see also topic "range extender")

Timo | November 9, 2010

Which part of the Europe are you living? 35A main breaker for each phase is common, so it is 400V@3*35A (but obviously you can't use it all without blowing a fuse). Even with just 400V@3*25A you still have 400V@75A.

I wouldn't buy that lump of ICE not-so-serial hybrid Volt (Ampera) for any price. I rather get PHEV Prius. Model S is in completely different category than that one. In just few years you would need to sell that obsolete tech hybrid for scrap money, because BEV:s are so much better.

Volt or Ampera is just PHEV with a bit more pure BEV range than Prius has unless you drive fast, then it uses that ICE for extra oomph its batteries lack. It is obsolete thinking in every single way. It is not serial hybrid with range extender generator even that GM wants you to think it is.

Model S is a future car, valid tech for few next decades with just battery upgrades. Probably valid tech until we have small fusion reactors for cars.

Perbear | November 9, 2010

European Single phase voltage is 230V. European three phase voltage is 400V (except in in very old electrical installations).

So using three phase charger instead of single phase charges your car three times faster using a single mains wire extra.

It seems that the US EV charge connector standard (SAE J1772) lack the possibility of supplying three phase. Fortunately, the suggested standard charge connectors mandated for European charging posts have included the pin missing in the US standard.

It would be neat if the Tesla S built-in charger supports three phase. Then it can charge three times faster without the need for larger fuses/amperage or an expensive dedicated charger, both seems quite costly to install.

Roblab | November 10, 2010

Don't know if it will make any difference, but the NiMH batteries did NOT like to have a lot of current dumped into them. It generally shortened battery life. Most people that have charged EVs seem to come to the conclusion that the slower you can charge your pack, the longer it will last. Since it is full every morning, you nearly always have enough for the day without topping off anywhere. Then a liesurely charge overnight(personally, I work and drive less than 12 hours a day, so the night is just for charging)and if you need to run to the store for something, you just unplug, go, come back, replug. It takes a LOT less time than driving to the gas station. Anyway, the bottom line is: You usually don't need to high-level charge, and it probably isn't good for your car.

Vawlkus | November 12, 2010

Since Tesla is, for now, using LiIon batteries, the high voltage concerns are no longer a factor. The higher voltage is simply to get power into the battery at a speed that the customer can live with. We're not at the speed of a gas fillup (yet }BD )but we're working towards it.

Of late I have been wondering if the capacitor idea would be practical for a recharging station, since they're too big to stick in the cars. Have them gradually soak up power from the grid using a charging circuit, then dump it into the car battery all in one go. It'd be a quick charge if the car can handle a dump like that, but it might bring up a wait time between car charges, while the caps fill again.

Timo | November 12, 2010

I did see a while a back some scientific paper about absolutely hilarious power densities in some new li-ion batteries. Apparently there are ways in nanotech to build up "conductive corridors" between anode and cathode so that that battery got something like 1MW/kg power density or some other ludicrously high figure.

That also mean that that battery could be fully charged in seconds....if you could find out a way to actually create that kind of currents and voltages without burning everything up.

ScepticMatt | November 12, 2010

I hope hope hope that 3 phase charging will be available. Those plugs are really abundant in Europe. And powerful too. So why not use them?

Timo | November 12, 2010

Looking at the recent blog it looks like European Roadster can use standard three-phase 400V@32A connector with mobile charger. There are two pictures where this dude had his car plugged in to those.

Kevin Sharpe | November 13, 2010

Just so that everyone is up to date.... the blogger has confirmed that the Roadster is being charge from one phase of the three phase supply. I do not know about the Model S but every conversation I've had with Tesla confirms that three phase charging for the Roadster is unlikely.

Bosko | November 18, 2010

I read this coment to a edmunds.com article. Does this persons agruement hold water? "Now hold on there, you may be partially correct. I believe most homes in America only have a 100 Amp service, the 200 Amp standatd was introduced around the early 90's so if your house is an older one you may have to have a new service brought into your house to use the 220 option. In addition if you only have a 100 Amp service and your air conditioner comes on at the same time your charging you will probably blow the main breaker (70 + 30 = 100) . Even if you have a 200 Amp service and dual air conditioners (which many larger homes have today) and an electric oven and they all came on at the same time you would probably be maxing out your service and again blow the main breaker.

So with that in mind I believe that the 3 to four 4 hour charging time to me is a little unrealistic. I would also like to know what the cool down time is for the battery after you charge it. Putting 53,000 watts in something for almost 4 hours creats a lot of heat and we all know how batteries like heat. Normally you have a cooling cycle to allow the battery to reach a "normal operating temperature" before you use it. What is the cool down time for your battery before use????

Another question I have is what happens to the performance and range of the battery in colder climates....batteries don't like the cold either it decreases their performance.....do you have a heater for your batteries??? If so how does the heater effect the range??"

Douglas3 | November 18, 2010

I'm talking about a Roadster here, but it all will apply equally to the Model S.

I have the 70A charger, but I rarely use it at full power. I have it programmed to charge at 40A starting at 1am. The car is fully charged well before I wake up.

In reality 240V 30A is plenty of capacity for an overnight charge. Late at night your air conditioning is not running much, and you're not cooking or using other energy-intensive appliances. You should have no problem selecting a charge level that doesn't blow your breakers even if you do have 100A service.

The battery is cooled during charging; that's the main reason why the car has an air conditioning system. No cool down time will be required. In fact in Range mode it actually chills the battery.

The Roadster also heats the battery when it is too cold. So again performance isn't the issue. All you'll see is a small amount of lost mileage if you leave it parked outside for a long time.

eberhard | November 22, 2010

Charging power is most important while running on long distances to shorten the breaks.
2.5 hour charging my roadster with 400V/32A and 22kW would change all. En
The roadster does regen-braking from the AC-engine up to 40kW. Thats mean, that the PEM is already prepared to change 3 Phase AC current from the engine to DC.

Its only a political decision by Tesla if they will support 3 Phase AC or not.

Timo | November 22, 2010

400V@32A is, if I understand that correctly, 32A / wire, so 3*32 max current. 400V@96A = 38.4kW. That would charge Roadster in just 1.5 hours.

That's fast enough to allow comfortable long road trips thru entire Europe (if you can find those chargers in less than 200mile distance apart).

Good point about regen braking. That really means that PEM can handle high voltage three phase currents.

qwk | November 23, 2010

The only problem I see with this is battery longevity. I would bet the reason Tesla chose not to initiate quick charges with the roadster is the battery cells are off the shelf laptop units. The last thing Tesla needs is a bunch of premature battery problems. This would certainly tarnish Tesla and the EV in general.

The Model S is supposed to come with specific automotive application designed cells, so that is why you see the quick charge option on the Model S.

Timo | November 23, 2010

Considering that it already does up to 40kW three-phase charging with regenerative braking, same thing from grid should not be any different for battery longevity. Obviously that kind of charging would be very small part of all driving.

Also, Roadster is what it is, we can't change that, but for Model S I don't see any reason not to include that possibility in European models. It certainly is not technical limitation, you only need a mobile charger with right kind of plug for that.

qwk | November 23, 2010

The percentage of time it's regenerating at near 40kw is very small. Totally different scenario than an hour charge.

Timo | November 23, 2010

Still it would be only a very small part of all driving. This is completely academic for Roadster anyway, it is what it is. Model S however could use that charging: they claim 45 minute charging possibility, which is way faster than that, so there should not be any reason to include that possibility in Model S.

qwk | November 23, 2010

You just restated what I posted above.

Timo | November 23, 2010

...to not include... (I know, I know, double negative).

Timo | November 23, 2010

Not quite restated. With "only very small part of all driving" I didn't mean regen, but recharging using that powerful connection. Home daily recharging can be much slower and still be fast enough. Sorry if I was not clear about that.

qwk | November 23, 2010

You and I would probably be smart enough to realize that, but not everyone is. Some people do things just because they can. That's probably why Tesla wen't with the "better safe than sorry" scenario.

bhp | November 23, 2010

There is no way to solve this problem !!!!!!!!!!!!!

It all depends on the charge curve of the battery/cell.

max safe charging is 2C i guess for "high energy cells"

if its "LiFePo4" then the case is totally different, because its "high power cell".

Model S: is using high energy cell it seems because of the Ah it gives is around 2.95Ah @ 3.6Volts !!!!! so its high energy cell for sure.......and you cannot do fast charging for high energy cell.

_____________________________________________________________________
Well, actually you can do 45 minutes fast charging via level 3 charger.......but this will reduce life cycles of the battery pack.

And more over you cannot completely charge the battery pack....lets say upto 75-80% may be.......not more than that.

BYT | November 23, 2010

Pixy Dust, that is your answer! Happy Thanksgiving everyone!

jkirkebo | November 26, 2010

32A 400V 3~ is 22kW, not 38.4kW. You have to multiply bu the square of 3 as 400V is only available between the phases. To neutral the voltage is 230V so the equation is either 400V*32A*SQ(3) or 230V*32A*3, both equals 22kW.

eberhard | November 26, 2010

And the PEM can already handle this without modification. He is already doing this while regen-braking

Timo | November 27, 2010

@jkirkebo do I really need to use SQ(3) for amps too, when that's not constant, but just max what panel can handle for single phase? IOW does it drop the amps in the output to 55A when it maxes out to panel at 3*32A = 96A? That sounds odd.

jkirkebo | November 27, 2010

The equation is for watts, not amps (V*A=W for a pure resistive load). When you connect a 3-phase load to a 400V 3~ supply, the load sees 400V only between the phases, L1 to L2, L2 to L3 and L3 to L1 (delta connection). Between the phases and neutral (L1 to N, L2 to N and L3 to N), the load sees only 230V (star connection). 400V*SQ(3) equals 230V so it doesn't matter if the load is delta or star connected, it can only draw 22kW max anyway.

Think of this another way, delta connected (400V) L1 has a load between itself and both L2 & L3. L2 & L3 are 120 degrees out of phase from L1 so you can't draw 32A from both loads as the total would exceed 32A on L1.

Star connected (L1/L2/L3 to neutral you can draw 32A on all loads but the voltage is only 230V phase to neutral.

Norway has a different 3~ system with 230V between phases and 130V to earth. Neutral doesn't exsist in this system and all loads are connected between phases instead. Here we thus have to use both 230V and SQ(3) to compute watts, a 3~ 230V 32A supply is then capable of delivering ~12.7kW instead of 22kW for 400V systems.

Timo | November 27, 2010

I still didn't get it. How come you can't have combined loads between phases go over 32A when both phases have 32A max separate load?

jkirkebo | November 28, 2010

Because L1 has a load between itself and both L2 & L3. If you draw 32A between L1 & L2 and 32A between L1 & L3, the combined load on L1 far exceeds 32A. Not two times 32A though, as the loads are 120 degrees out of phase.

You can draw ~18.5A on both loads simulaneously, that will result in a 32A load on the L1 wire.