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I understand one can use 240 volt at home so how does D C Fast Charging differ? Larger current delivery?

Thanks, Harry
 

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240 volt charging doubles the voltage going to your car over your home's alternating current (AC) wiring connection. This is the same as most air conditioners, well pumps, electric furnaces, etc. This reduces your charging times by a little more than half.

DCFC = Direct Current Fast Charging. This is typically only from local public charging stations and can pump massive amounts of electricity into a battery in a short period of time. This is what you'd be using if you were going on a road trip, assuming it's available.
 

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240V "L2" charging uses the voltage already present in your home, two 120VAC phases. The charger is in the car.

DCFC uses an external charge controller of 300-500VDC, that provides the precise DC voltage (or max current) that the car requests. It is also designed to provide more current (more total power) than L2.

DCFC stations can span a large range of power and cost, since the primary electronic control is external. It moves much of the cost of the charging electronics from car to station. The car, however, must carefully tell the station exactly what it needs.
 

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...DCFC stations can span a large range of power and cost, ..
I know of common the 50kW DCFC stations with, (either or both) cords to feed cars with CCS/SAE or Chademo capabilities.
There are some 25kW DCFC stations, somewhere..

Cost? Networks, not people, are concerned about price.

And then,, there is the Tesla Supercharger network, (100kW). But it has been reported that they don't play well with others.
 

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I know of common the 50kW DCFC stations with, (either or both) cords to feed cars with CCS/SAE or Chademo capabilities.
There are some 25kW DCFC stations, somewhere..

Cost? Networks, not people, are concerned about price.

And then,, there is the Tesla Supercharger network, (100kW). But it has been reported that they don't play well with others.
Actually most of Tesla's Superchargers are now capable of 140KW. But they have very few cars that can actually take good advantage of that charge rate.

You are correct most CCS/CHAdeMO stations that exist are 50KW. There are some that are 60KW. Many BMW dealers are putting in 24KW CCS only stations.

I think part of the issue is that CCS currently can go up to 100KW but CHAdeMO can't. CHAdeMO currently maxes out at 500VDC at 125A. (62.5KW) [This is a limit of the connector]. So any dual station will likely be limited to 60KW for now.
 

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Well there's a little more to it that that. The Supercharger stations share power between two plugs so the 125kW or 140kW power is split when two cars are charging on the paired unit. Also, I'm not sure if any of the Tesla's can use the full 140kW. I've read one report of an S P100D charging at a peak of about 120kW, but that could have been at a 125kW Supercharger, not a 140kW unit.

The CHAdeMO standard is capable of 100kW (500V @ 200A) but there aren't any cars in the US that could charge faster than the Soul EV at ~72 kW (360V @ 200A). But I don't have a feel for how many CHAdeMO stations even exist above 50 kW. There's also this ominous quote on the CHAdeMO website, "the majority of utility companies around the world support CHAdeMO’s view in eventually setting the most appropriate power level at 50KW."

Anyway, the whole DC fast charging situation is evolving pretty rapidly.
 

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One question that has not been asked by the others is "What car do you have?". You are on the Volt forum, so it's quite possible that you are asking about a Volt? The Volt is not designed for DC quick charging. DC quick charging is only for pure electric cars so that when the battery is depleted the car can be "re-fueled" in a relatively short time. This would enable a BEV owner to journey beyond the vehicle's electric range. The Volt's back-up plan is the gasoline engine. When the Volt ventures beyond it's electric range the gasoline engine is used to create electricity, and the gasoline can be re-filled at any gas station just like any ICE car. So there is no way to DC quick charge a Volt. The pure electric is a much simpler design and as on-board batteries get larger the car becomes more appealing to a larger group of people. The electric's achilles heel is it's re-fueling time. So DC fast charging is the answer to shorter re-charging times.
 

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One question that has not been asked by the others is "What car do you have?". You are on the Volt forum, so it's quite possible that you are asking about a Volt? The Volt is not designed for DC quick charging. DC quick charging is only for pure electric cars so that when the battery is depleted the car can be "re-fueled" in a relatively short time. This would enable a BEV owner to journey beyond the vehicle's electric range. The Volt's back-up plan is the gasoline engine. When the Volt ventures beyond it's electric range the gasoline engine is used to create electricity, and the gasoline can be re-filled at any gas station just like any ICE car. So there is no way to DC quick charge a Volt. The pure electric is a much simpler design and as on-board batteries get larger the car becomes more appealing to a larger group of people. The electric's achilles heel is it's re-fueling time. So DC fast charging is the answer to shorter re-charging times.
Now I'm confused! I thought this was a Bolt EV forum.
 

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Be advised that many L2 chargers at commercial sites are not 240v but rather 208v...While the numbers may not sound like a big deal, for the Gen2 Volt it increases the 0-100% charging time from 4.5 hours to 5.5 hours; just under a 20% increase in time...
 

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I've seen output vary between 220v and 240v in different areas. That's why just about everything runs through a power supply of some sort to level it out. 208v isn't that far off, but yeah you're going to take longer to charge.
 
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