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It's not possible
It's Fisker - the well known con

700 miles range is what 250 Kwhrs? - in one minute is 15 Mega Watts

At 1000 volts that is 15,000 Amps

And that is assuming zero losses!

It's a con from a known con man
 

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Practically, its not possible because every battery takes time to recharge for 1 hours or more time. So, this range would be a myth.
NO NOT at all

Batteries used in EV's can be charged a LOT faster than 1 hour!

That is called a 1C rate

Charging at 4C is not uncommon - and can give a full charge in about 20 minutes

20C is eminently possible with a battery that is designed to do that
 

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Could someone please explain to me how this is possible ?
Some background (here)... Fisker is one of those companies you love or hate (especially for Tesla fans)... time will tell whether any of these claims are 'real'... personally I hope they are, we really need a step change in battery storage capabilities :)
 

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It's not possible
It's Fisker - the well known con

700 miles range is what 250 Kwhrs? - in one minute is 15 Mega Watts

At 1000 volts that is 15,000 Amps

And that is assuming zero losses!

It's a con from a known con man
And just think, nothing is 100% efficient. The inefficiency primarily presents as heat. If the process were 95% efficient then you'd have about 750 kilowatts of heat generated over the course of 1 minute. That's a lot of heat. It's equivalent to burning about a quart of gasoline over that one minute interval. To my knowledge charging tends to be ever worse than 95% efficient so the losses only increase from there.

I don't know of anything other than a capacitor that could even handle a charging speed nearly this fast. What sort of cabling would you even use?! 15kA is quite a lot of current. If online calculators are to be believed, you'd need something like a 300mm diameter cable?!
 

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700 miles range is what 250 Kwhrs? - in one minute is 15 Mega Watts
Playing devils advocate, Tesla are already claiming 1.6MW on the Semi using an 8 pin charge port (here)... are we really saying that Fiskers claims are *impossible* or they are simply beyond anything that we can imagine today :p
 

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You're looking at electrically recharging. How about mechanical recharge? Like replacing the electrolyte in a flow battery. Or I think there is a zinc battery where the charge resides on the zinc itself and a spool of zinc ribbon is passed through a reaction chamber. Then recharging is reduced to exchanging a spool of zinc. Or just swap the entire battery. These approaches can be done very quickly.

Actually most folks will use EVs like I do. Almost every recharge occurs in my garage overnight. Three to five hours is no problem. I appreciate the long trip and fast refuel desire. I think other solutions will be developed, like periodic "charge lanes" where you can recharge while driving.

Be interesting to see how it plays out.

major
 

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Playing devils advocate, Tesla are already claiming 1.6MW on the Semi using an 8 pin charge port (here)... are we really saying that Fiskers claims are *impossible* or they are simply beyond anything that we can imagine today :p

Tesla already do what 300 Kw? with two pins so eight would do about 1200Kw

Sounds doable - but that would be a "Truck Sized" connector


The Fisker is 10 times as much again! - and in a car so that grandma has to be able to plug it in
 

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Tesla already do what 300 Kw? with two pins so eight would do about 1200Kw

Sounds doable - but that would be a "Truck Sized" connector
I'm not sure what you think a "Truck Sized" connector looks like, but the 1.6MW connector fitted to the Tesla Semi is about the size of an adult male palm (see photo), indeed it's smaller than most CHAdeMO plugs that I've used :)

See this video for more details;

 

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I'm not sure what you think a "Truck Sized" connector looks like, but the 1.6MW connector fitted to the Tesla Semi is about the size of an adult male palm (see photo), indeed it's smaller than most CHAdeMO plugs that I've used :)
Do you think Tesla has actually charged a Semi at the claimed rate to the claimed capacity with this connector (or any connector)? Since the current prototype is for show, with specs that are generally phrased as characteristics of the truck which will exist in a few years, and many technical details are deliberately not mentioned, I suspect that the connector is "conceptual". ;) I'm not suggesting that it's just fiction, but it also seems unlikely that it is a complete and proven design.
 

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Do you think Tesla has actually charged a Semi at the claimed rate to the claimed capacity with this connector (or any connector)?
Who knows? If you start doubting what Musk says then what about the rest of the semi or 2020 Roadster announcements ;)

What we do know from the Model S/X is that Tesla use very small cables for their power conductors. The outside diameter of the four power conductors on the EU charge connector is 10.6mm (25mm2 cable?) and the US charge connector drops this to just two power conductors although they are slightly larger diameter iirc.

In 2015 Tesla claimed Superchargers supported 145kW, limited to 120kW by the car, according to disclosures made during the UK ASA Complaint (here). In 2016 Musk said that Supercharger V3 will exceed 350kW (maybe that's now called the 'Megacharger' and needs a new connector?).

Whatever you believe, it is interesting to consider the length of DC power conductor used in the Tesla Supercharger architecture. Conductors travels from the bank of chargers in the Supercharger cabinet, across the forecourt, in/out the Supercharger 'stand', into the car, through the HVJB, and then finally into the battery... that's a long way :eek:
 

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There is a rumor about, that some months ago, a Semi used a group of 4 Superchargers at once for a recharge. The people in charge of the Supercharger system noticed late one night, at a station near the Fremont plant, a group of 4 Superchargers going on and off at the same time and drawing a huge amount of power!
 

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Whatever you believe, it is interesting to consider the length of DC power conductor used in the Tesla Supercharger architecture. Conductors travels from the bank of chargers in the Supercharger cabinet, across the forecourt, in/out the Supercharger 'stand', into the car, through the HVJB, and then finally into the battery... that's a long way :eek:
It's a long way if it consists of conductors which are too small. It's not unreasonably far for properly sized 400 volt power cables.
 

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It's a long way if it consists of conductors which are too small. It's not unreasonably far for properly sized 400 volt power cables.
Sure... thankfully we don't have to guess at the Supercharger site details because they're available online (here) :)
 

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Sure... thankfully we don't have to guess at the Supercharger site details because they're available online (here) :)
Nice :)

Sheet E-3 has the conductor specs and confirms that the run from the substation transformer to the Supercharger cabinet is much larger (greater cross-section) conductor (and it's short in this particular installation anyway). Sheet E-2 has the lengths from there, which are not long for runs of a few hundred volts (comparable to those in a house or commercial

The longest bits are in the smallest conductor size, but are only carrying one car worth of current. These conductors are 250MCM, which is apparently an antique designation meaning thousands of circular mils. That's the first standard size larger than 0000 AWG, and has 126.7 mm2 area; it's good for 290 amps, so it's running right up to its limit... but not beyond that.
 
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