Supercharger V3 over 350kW

[TonyWilliams]

Got it, was wondering if someone has compiled a list of packs/Rev's and capacities that have max charge limits? I have a newly acquired 70d but it's been pretty cold and never seen it go over 1.2c.

But it's never been down below 41% or above 60* either! Today is 70* plus so I'll find out.

The maximum charge rate for:


Small battery 60-70-75 kWh cars (excludes early 60) - 354 volts max

365 -370 amps at about 320 volts (17% SOC) = 116kW


Big battery cars 85-90-100 kWh (exclude 90kW limited "A" packs) - 403 volts max

330 - 335 amps at about 350 - 365 volts (Low% SOC) = 118kW

 

[JasonA-EV]

Awesome! thanks Tony!

I'll never see those levels unless I get it that low then.

 

[henderrj]

I'm really wondering if this has anything to do with cars at all. Maybe this is all about the Tesla semis. Or perhaps even the pickup. I don't think they're going to do cars but it might be byproduct of what they developed for the semis.

As to increases in voltage or amperage. As someone mentioned more amperage equals more heat. But more voltage equals greater potential for arcing. I'm not sure they can use the current connector at all. (As a point of reference I have a patent pending for a charging system, it uses a lot bigger connectors to get a thousand volts and amps!)

 

[scaesare]

The maximum charge rate for:


Small battery 60-70-75 kWh cars (excludes early 60) - 354 volts max

365 -370 amps at about 320 volts (17% SOC) = 116kW


Big battery cars 85-90-100 kWh (exclude 90kW limited "A" packs) - 403 volts max

330 - 335 amps at about 350 - 365 volts (Low% SOC) = 118kW

The smaller packs actually draw MORE current?

Interesting... that may imply the limitation is the total power deliver. I wonder if that's on the supercharger side somehow, perhaps needing to keep under 120kW total for some reason, despite the existence of 135KW (and I believe 150's in Europe). Or perhaps pack cooling limits...

If the larger pack cars could draw an additional 10% more current, we'd be looking at maxing out a 135KW supercharger...

 

[Gen3]

[QUOTE=" (As a point of reference I have a patent pending for a charging system, it uses a lot bigger connectors to get a thousand volts and amps!)[/QUOTE]


Care to share a pic?

 

[TonyWilliams]

The smaller packs actually draw MORE current?

Interesting... that may imply the limitation is the total power deliver. I wonder if that's on the supercharger side somehow, perhaps needing to keep under 120kW total for some reason, despite the existence of 135KW (and I believe 150's in Europe). Or perhaps pack cooling limits...

If the larger pack cars could draw an additional 10% more current, we'd be looking at maxing out a 135KW supercharger...

Yes, small battery cars MUST pull more amperage to charge at "120kW", and the 145kW upgrade allowed that to happen.

The 12 chargers in each Supercharger are pulling 40 amps @ 277 volts = 11kW, or 132kW AC power pulled from the grid. Using a generic 90% efficiency for a conversion to DC, we get... drum roll... 120kW.

But, the big battery / higher voltage cars were already pulling 120kW DC prior to the first 70D, so to make a small battery / lower voltage car capable of the same 120kW required a big bump in amps.

My belief is that this is what the "145kW" upgrade is. Whether one car, or two on a Supercharger, an overall load greater than 120kW is impossible on a "135kW" charger, but maybe the "145kW" charger can? Each of those modules must be bumped up to about 12kW AC, so about 130kW DC theoretical output... two cars at 65kW?

Using 365A * 400V = 146kW DC / 160kW AC... that no car can use. Trying to operate the big battery cars at 365 amps is probably entirely possible, if the overall power is kept below 120kW DC, plus any additional heat dissipation that is required is resolved (there shouldn't be much issue with heat if the power is kept below 120kW).

That would be an exceptionally low maximum voltage of about 328 volts max for a big battery car, so any advantage would be at the absolutley lowest battery levels... well below the "knee" of the cells.

 

[ecobon]

Sorry, not sure I understand your question. Install a hypercharger (or 2) at each existing location. People would be out in 10-15 minutes so there shouldn't be much congestion. And they've clearly stated unlimited free supercharging is done so yes, they can charge a premium for ultrafast charging. Not a profit center but enough to offset the cost. If I was in a rush I'd gladly pay the equivalent of a tank of gas to be full in almost the same time it would take to pump gas. If I wasn't in a rush I'd plug into a regular SC stall and get a coffee.

I know it's been mentioned that service centers and superchargers not being initially thought of as profit centers, but if it starts to create profit and can be sustained while keeping patrons happy, it could or should [would] be a profit center. The CEO does state such as it's good PR for a strong movement against the traditional dealership mentality of fleecing their customers. Profit doesn't mean they have to fleece us!

I concur as well and would like to see a faster charging option where we can pay to get back on the road faster (and not eat at some of the fast food stands just to support them for hosting superchargers).

 

[scaesare]

You know, I 've gone back and I can't find that I took any pics... but now that you have me thinking, I wonder if I've mis-remembered that as 124, and not 134.

If so, that would be a C rate of about 1.46. Unless I find proof my earlier assertion is correct (and based on a quick google search, I suspect it's not), that's probably better data to go by.

Apologies for any misinformation, and thanks @stopcrazypp for the sanity-check.

To update this, I did come across this page which demonstrates a 70kWh car charging at 117kW, which is indeed a ~1.7C rate...

 

[henderrj]

[QUOTE=" (As a point of reference I have a patent pending for a charging system, it uses a lot bigger connectors to get a thousand volts and amps!)

Care to share a pic?[/QUOTE]

PM sent

 

[scaesare]

Yes, small battery cars MUST pull more amperage to charge at "120kW", and the 145kW upgrade allowed that to happen.

The 12 chargers in each Supercharger are pulling 40 amps @ 277 volts = 11kW, or 132kW AC power pulled from the grid. Using a generic 90% efficiency for a conversion to DC, we get... drum roll... 120kW.

But, the big battery / higher voltage cars were already pulling 120kW DC prior to the first 70D, so to make a small battery / lower voltage car capable of the same 120kW required a big bump in amps.

My belief is that this is what the "145kW" upgrade is. Whether one car, or two on a Supercharger, an overall load greater than 120kW is impossible on a "135kW" charger, but maybe the "145kW" charger can? Each of those modules must be bumped up to about 12kW AC, so about 130kW DC theoretical output... two cars at 65kW?

Using 365A * 400V = 146kW DC / 160kW AC... that no car can use. Trying to operate the big battery cars at 365 amps is probably entirely possible, if the overall power is kept below 120kW DC, plus any additional heat dissipation that is required is resolved (there shouldn't be much issue with heat if the power is kept below 120kW).

That would be an exceptionally low maximum voltage of about 328 volts max for a big battery car, so any advantage would be at the absolutley lowest battery levels... well below the "knee" of the cells.

Thanks @TonyWilliams... I hadn't been paying attention to the newer packs, and didn't realize they were pulling greater current than the older 60's and even 85's.

I had assumed the chargers were delivering their current limit, but indeed it appears the pack may have been the limiting factor for the lower-voltage packs.

Quite frankly it makes it all the more impressive that the Tesla connector is capable of at least 365A. It would indeed me cool to see what a 100kW pack would be capable of if there were no Supercharger-side power delivery limitations...

 

[TonyWilliams]

Quite frankly it makes it all the more impressive that the Tesla connector is capable of at least 365A. It would indeed me cool to see what a 100kW pack would be capable of if there were no Supercharger-side power delivery limitations...

I'm confident that the pack could handle more power, I'm not as confident that the vehicle cooling system can.

The bigger the battery, the larger the waste heat problem is. If we apply the same 1.6 to 1.7 "C" rate that a 70kWh can handle at 120kW to a 100kWh battery, then 160-170kW is likely possible. Again,while the Supercharger is obviously limited, the vehicle cooling system is now required to discharge 100 / 70 = 43% more heat at the same "C" rate.

I'm not sure what cell they are using to make the biggest battery car, since the pack is allegedly "rearranged" but has the same number of cells:

7104 cells * (3900mah * 3.65v) = "100kWh" ????
7104 cells * (3400mah * 3.65v) = 88.1kWh ("90" car)
7104 cells * (3100mah * 3.65v) = 80.4kWh ("85" car)
6216 cells * (3400mah * 3.65v) = 77.1kWh ("75" car and software limited "60")
6216 cells * (3100mah * 3.65v) = 71.3kWh ("70" car)
5040 cells * (3100mah * 3.65v) = 57.0kWh ("60" car and software limited "40")

 

[MP3Mike]

I'm not sure what cell they are using to make the biggest battery car, since the pack is allegedly "rearranged" but has the same number of cells:

No, they said that they used the same cells in the 100kWh pack, but completely redesigned the cooling and internal components to fit more cells in.

 

[scaesare]

No, they said that they used the same cells in the 100kWh pack, but completely redesigned the cooling and internal components to fit more cells in.

This was my understanding as well.

Or to be more precise: the 90's were same number of cells (7104), but with upgraded chemistry for greater capacity, whereas the 100's were a greater number of those newer cells.

 

[TonyWilliams]

This was my understanding as well.

Or to be more precise: the 90's were same number of cells (7104), but with upgraded chemistry for greater capacity, whereas the 100's were a greater number of those newer cells.

Ok, well it has to be some multiple of 96 cells in series... the big battery 85-90 cars are 96s x 74p. They can't change the series cell count very easily, and since the 70-75 packs are 84 in series, it makes logical sense that the new "100kWh" pack is:

96s * 84p = 8064

8064 cells * (3400mah * 3.65v) = 100kWh ("100" car)
7104 cells * (3400mah * 3.65v) = 88.1kWh ("90" car)
7104 cells * (3100mah * 3.65v) = 80.4kWh ("85" car)
6216 cells * (3400mah * 3.65v) = 77.1kWh ("75" car and software limited "60")
6216 cells * (3100mah * 3.65v) = 71.3kWh ("70" car)
5040 cells * (3100mah * 3.65v) = 57.0kWh ("60" car and software limited "40")

 

[scaesare]

That's about the same count I figured as well.