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Tesla are about to introduce the next version of the Supercharger station, with available power in excess of 350 kW per stall.

Elon Musk teases new ‘Tesla Supercharger V3’ with over 350 kW power output and off-grid solar + Powerpacks

They're looking to integrate solar PV and powerpacks in an attempt to make them self sufficient. I imagine this will also reduce dependency on local electrical capacity, so you get a more consistent charge.

Guesses on a postcard for what the actual power and charge time will be.
 

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Adding powerpacks is a good idea to avoid overloading the local supply and level the load out. 350kW would get a lot closer to petrol pump times but would need a different battery chemistry to enable. 120kW is pretty much the max for the current Model S and I suspect 150kW is about the limit for the current plugs so maybe that's where CCS comes in with the Model 3 and new battery cells?
 

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I remember higher powered charging being discussed here before; heat dissipation being a particular problem.

That aside, a site is going to need millions of dollars of Powerpacks and solar cells to work. I'm sure it could be built; but I wonder how the cost could be recouped.
 

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I genuinely don't see how they are going to get twice the current through the cabling on the existing stalls. Even throwing water cooling into the mix, they surely will need to up the voltage to hit 350 kW (if mere mortals are to lift the cables).

Any increase in charging voltage is very likely to mean a significant future change to the cars to take advantage of it.
 

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I genuinely don't see how they are going to get twice the current through the cabling on the existing stalls. Even throwing water cooling into the mix, they surely will need to up the voltage to hit 350 kW (if mere mortals are to lift the cables).

Any increase in charging voltage is very likely to mean a significant future change to the cars to take advantage of it.
Peak at 1,000v instead of 400v, easy 300kw with existing cabling (and maybe connector. Probably)

Twin cables is an option, and robotic snake superchargers are also an option - who cares if a man can't lift it if it's a robot doing it.
 

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And quite how is the existing fleet going to use 1000v?

It certainly isnt as easy as sending out a tweet (or OTA update.)

You also have some significant issues in regards insulation, which typically is rated around 600v.

As for metal snakes....


TBH it all sounds a preemptive tweet in advance of likely poor Q4 delivery and financial performance.
 

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I think there's only two reasonable interpretations:
  1. This is a long term announcement, not pertinent to current or near-future vehicles. Tesla does make that sort of announcement from time to time.
  2. It means something less exciting than it first appears. Maybe it's not a response to the high-voltage reports from Porsche et al (which is also a long-term thing), maybe it's a response to the other announcements from chargepoint manufacturers about kit you might be able to buy shortly - multi-headed CHAdeMO/CCS chargepoints that can do higher powers split between multiple heads. Note that the Electrek article is cobbled together from multiple tweets that don't necessarily all relate to the same kit.
Note as an aside that we've been expecting a Supercharger V3 for a while - using the new 16.5kW charger modules from facelift model S (Supercharger V2 used the 11kW modules from EU Model S, which at USA voltages gave 13kW input; Supercharger V1 used the 40A single-phase modules from original N.America Model S at 11kW input rating). It's quite possible that they will choose to make it a 4-way rather than 2-way sharing unit with a few more modules in it, or some other reconfiguration.

The stuff about solar power/batteries puzzles me. My assumption was that the original idea had been killed off by success - if you have fairly low demand (2 or 4 stalls), then you expect it to be idle most of the time and a battery pack makes a lot of sense as you can average that demand and use a smaller grid connection (or solar can make a useful amount of difference). But once they got up to 8/12/16-stall sites, which correspond to much higher utilisation levels, then the battery would have to be enormous to make a difference and even then it takes you from an enormous grid connection merely down to one of middling huge size, wheras in with smaller sites it could take you down from large to small enough that you can find existing power on the site.
 

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And quite how is the existing fleet going to use 1000v?

It certainly isnt as easy as sending out a tweet (or OTA update.)

You also have some significant issues in regards insulation, which typically is rated around 600v.

As for metal snakes....


TBH it all sounds a preemptive tweet in advance of likely poor Q4 delivery and financial performance.
I never said the existing fleet could use 1,000v. Hook them up and they'll still be limited to whatever voltage/current they can cope with, just like how the early S's are limited to 90kw even on new superchargers.
 

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@arg completely agree with you.

Using the new larger charger modules would be somewhat of a no-brainer in any new install, and possibly make sense on busier sites to do an early hardware refresh (as you say that could give them better load sharing between stalls improving site throughput). A complete network upgrade would be really unlikely IMHO, as it would mean early writing off of many sites, and a big hit on the financials.

We have the Mission-e, the Audi Q6 etron, and the Jag iPace all hinting at higher pack voltages and subsequent improvements in charging rates.Unencumbered with the significant existing infrastructure investment the other manufacturers may be playing to Tesla's natural first mover disadvantage.

Certainly in the US where VW are mandated to rollout a $2bn EV charging system as part of their penance for dieselgate they have been dragging their heels. I wonder if this is waiting for higher charge rate stations to become commercially available, or they actually need cars that can take advantage of it?

This is certainly a bear case thesis that is gaining traction, and one thing I've noticed over the years is Elon attempts to discredit these criticisms in 140 characters or less.

Either way I would suggest 2018 is going to be a very exciting year for EV's and that is the "long term" timescale we are talking about here.

So when will Tesla have a vehicle capable of taking advantage of the next-gen chargers? It wouldn't surprise me if the Model 3 is the first, maybe with the S undergoing some significant pack changes to match.
 

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If you ramp a pack from 400V to 800V, what effect (if any) is there on the battery pack dimensions and packaging?

I assume the way Tesla would get an 800V pack is simply be connecting more batteries together so no net difference (and in fact they could perhaps come up with a bodgy replacement of existing car's packs by rewiring them to be in series instead of parallel, then using some sort of step-down transformer in front of the motor connections)

However, would new manufacturers with different approaches to building battery packs - using larger pouch modules for example - be able to use the higher voltage to shrink down e.g. interconnection wiring?
 

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The bears have been consistently wrong on the overall trend with Tesla (SolarCity merger not going to happen anyone?) but who cares what they think.
 

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@BlackLeaf I guess Tesla could "bifurcate" the pack. A couple of contactors switching between 8 modules in series when charging from higher voltage supplies, 8 modules in parallel when running or charging from the on board chargers / existing superchargers.

That would save a chunk of R&D work in redeveloping the underlying drivetrain/inverter/software architecture.
 

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@Simon Mac Good point - no need for the step down transformer to the motor then either.

Building all cars with a similar architecture would mean the existing infrastructure can stay in place and be available to all vehicle and thus maintain that first-mover advantage.

We should patent our idea before Musk makes an announcement!
 

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My take on this is that Musk is talking about the DC power electronics/rectifier box side of things (at least in the short term while cars can only take a max of 120ish kWs).

Given that all new SC sites are said to be either 8 or 12 stalls, it would make sense to install electronics cabinets able to serve 4 stalls at once with 350kW of power. This would mean that each stall is almost guaranteed to be able to charge current generation cars at full rate and would also have headroom to charge faster in the future if and when cars able to take advantage of this came along.
 

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It obviously won't work for the existing fleet but that doesn't mean it isn't happening - we'd probably see a preview of higher charging rate capability (whatever that ends up meaning) on an upcoming refresh of the Model S/X and as an option on the 3.
 

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Discussion Starter #17
It obviously won't work for the existing fleet but that doesn't mean it isn't happening - we'd probably see a preview of higher charging rate capability (whatever that ends up meaning) on an upcoming refresh of the Model S/X and as an option on the 3.
Why do you say it won't work for the existing fleet?
 

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@cah197 my take on why it won't work for the existing fleet is that sufficient Model S's have been taken apart (admittedly no P100D's which have significant changes) to reverse engineer the current wiring/battery set-up/ BMS systems etc, that mean it is VERY unlikely a Model S pre-2017 will be able to charge at a higher rate.

Simple example would be the cabling between the charge port and the main battery. It is already undersized (under US and EU guidelines of best practice in industrial use) for the continuous current a full 120kW charge would imply, relying somewhat on the fact that the margins have been pushed under the working assumption of current taper. Likewise the chargeport itself.

Equally the car's internal cabling is off the shelf 600v insulation rated, and pushing it to 800v (while not impossible as Tesla own both charger and car from a product liability POV) is probably a step too far.

Tesla's biggest advantage IMHO is not the tech, rather the legal rights they have over SpC site leases. There is a reason Ecotricity and Tesla had such a spat over the MSA's rights. No doubt VW will face a similar set of problems when they roll out their charging network in the U.S.
 

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@cah197

Simple example would be the cabling between the charge port and the main battery. It is already undersized (under US and EU guidelines of best practice in industrial use) for the continuous current a full 120kW charge would imply, relying somewhat on the fact that the margins have been pushed under the working assumption of current taper. Likewise the chargeport itself.

Equally the car's internal cabling is off the shelf 600v insulation rated, and pushing it to 800v (while not impossible as Tesla own both charger and car from a product liability POV) is probably a step too far.
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This is an interesting observation @Simon Mac. I was looking behind the little flap immdiately behind the charge port in the back of the boot of my own Model S recently. The cables struck me are being a bit on the 'light' side given the power they are being asked to carry. While I can see why they did this, it doesn't really inspire great confidence to see that corners have been cut in this way.

Mind, all this talk of super high powered chargers.... I've yet to see a supercharger power of >96kW on my own 60kWh software limited 75kWh battery. Although to be fair, I've also yet to get to a SC with less than 16% remaining, so it might be higher if I got there closer to empty.
 

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Could someone tell me why they would have used thinner cables? Cheapness, ease of using off-the-shelf parts, flexibility when threading through the bulkheads?
 
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