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New 2021 Model S battery cells & packs
- Thread starter MarcG
- Start date
There seemed to be a remarkably high level of speculation that Model S Plaid had something other than 18650 cells.
Well, here’s the smoking gun (sorry) that proves Elon’s tweet was correct.
Looks like the Model S Plaid is ~460V at 90% SOC
Maybe 112 cells in series? My LR Model 3 reported 401V at 90% SOC when Supercharging...
I'm impressed that they are allowing voltages that high - V4 SC cabinets appear to only be rated for 410V.
Maybe 112 cells in series? My LR Model 3 reported 401V at 90% SOC when Supercharging...
I'm impressed that they are allowing voltages that high - V4 SC cabinets appear to only be rated for 410V.
aerodyne
2 of 3 EV's - Defect Free!
Apparently, not advanced enough safety wise...lol
However, I find it odd how quickly the owner lawyered up.
I could speculate the owner was doing runs, lost control, hit something hard, rupturing the pack in the back, and left the car in such a hurry, not knowing how to operate the doors, the car was still in Drive..
I wonder if we will see more pics of the battery case that will let us know more about module arrangement..
I am still betting on the pack not being the primary cause. The story does not add up.
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Well, the fire of the plaid has proven my hunch incorrect. I was wrong.
Now I want to know what chemistry and cooling improvement they have made to get such performance from the 19650s and when they are coming to the 2170 packs!
LargeHamCollider
Battery cells != scalable
Just in case anyone has a tinfoil chapeau around, the owner of the burned plaid was Bart Smith, an executive at Susquehanna known as the “Crypto King” who leads crypto trading. Susquehanna has a hedge fund arm and they have historically been net short Tesla despite their MM arm owning tons of shares (and thus the media reporting that the firm is a huge Tesla investor).
No, Porsche doesn’t do this kind of physical pack reconfiguration. They have a fixed “800V” pack configuration (I don’t recall the exact nominal pack voltage offhand) and then have a DC-DC voltage converter to boost the voltage by 2X when using older CCS chargers that support only a peak of 500V.
Rivian has a patent for physical pack reconfiguration to deal with “400” vs “800” volt charging but the design seemed kludgy to me and at one point awhile ago Rivian denied to me that they were going to use that approach in their first-gen pickup and SUV.
This is a 3-year-old article that I wrote about the trade offs that is still relevant:
How does 800V charging work?
Porsche has been working on a new all-electric Mission E which will push the boundaries in a big way on ultra-fast charging. The brand aims to be the first production car that will charge at over 2…
electricrevs.com
Your linked article guesses that’s how Porsche does it. If there is a link to an article that describes it as an unswitched 800V pack, please post it.No, Porsche doesn’t do this kind of physical pack reconfiguration. They have a fixed “800V” pack configuration (I don’t recall the exact nominal pack voltage offhand) and then have a DC-DC voltage converter to boost the voltage by 2X when using older CCS chargers that support only a peak of 500V.
This is a 3-year-old article that I wrote about the trade offs that is still relevant:
How does 800V charging work?
Porsche has been working on a new all-electric Mission E which will push the boundaries in a big way on ultra-fast charging. The brand aims to be the first production car that will charge at over 2…
BigNick
Infamous Fat Sweaty Guy
AlanSubie4Life
Efficiency Obsessed Member
Thanks for the info. I don’t pay attention to Porsche much and I think some articles initially speculated about pack reconfiguration. Hence my uncertainty above.No, Porsche doesn’t do this kind of physical pack reconfiguration. They have a fixed “800V” pack configuration (I don’t recall the exact nominal pack voltage offhand) and then have a DC-DC voltage converter to boost the voltage by 2X when using older CCS chargers that support only a peak of 500V.
Rivian has a patent for physical pack reconfiguration to deal with “400” vs “800” volt charging but the design seemed kludgy to me and at one point awhile ago Rivian denied to me that they were going to use that approach in their first-gen pickup and SUV.
This is a 3-year-old article that I wrote about the trade offs that is still relevant:
How does 800V charging work?
Porsche has been working on a new all-electric Mission E which will push the boundaries in a big way on ultra-fast charging. The brand aims to be the first production car that will charge at over 2…
And the Porsche documentation confirms your article (says a DC charger is used). https://newsroom.porsche.com/dam/jc...8b845e321/PAG_Taycan_Technology_PM_EN.pdf.PDF
It sure would be awesome to see a similar document from Tesla on the Plaid powertrain. That will never happen though. Tesla doesn't need to convince buyers to commit, which is Porsche's fundamental motivation.
More on topic, do we have any hard evidence that Tesla isn't incorporating a similar system in these new packs and using an 800+V architecture for MS/MX/R2/CT? Obviously, Tesla lists only 450V nominal in the Owner's Manual, but 350kW from V4 Superchargers (at ~400V) is going to need more than 800A, which is a lot to ask of a cable that is manageable by the full spectrum of consumers.
AlanSubie4Life
Efficiency Obsessed Member
Do you know what is the limit of current on the current V3s? Isn’t it the max current right now around 700A-800A when at 250kW, low SoC? I haven’t gone to look at your tables…. But in any case with (perhaps) 25% higher voltage with the Plaid, wouldn’t that be just ~10% more current at 350kW? The V3 cables as is are pretty svelte…would they even have to get thicker for V4 (maybe to enable Cybertruck, they would…not sure what the exact plan is there)?
Within the article is an update noting a subsequent confirmation that Porsche actually did end up using DC to DC conversion.
The counter-argument is that Tesla is already pushing ~670A through the fairly flexible and modestly slim V3 charging cables and ~800A isn’t that much more. Seems doable with cables not worse than the existing 500A liquid-cooled CCS ones.
Yet it would seem to make a lot of sense for them to make the switch to 800V especially for the Semi. Although the new Semi connector supports up to 3000A it wouldn’t leave much margin on charging speed at ~400V and a pack big enough to go the 500 miles that Tesla discussed at one point.
If they do 800V components for the truck then it makes sense to share them with the next-gen high-end vehicles like R2 and maybe CT and future MS/MX. If that’s true then you would think that the V3 Superchargers should really be capable of up to 900-1000V even though the nameplate says 500V — a more extreme version of how the existing V2 chargers seem to be capable of ~460V even though the nameplate says they peak at 410V.
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The highest current I’ve seen reported or on video captures of V3 charging sessions is about 670A although it wouldn’t surprise me if they go a bit higher at ~10% SOC for a short time.
V3 amperage is high 600's for the Model 3/Y packs at low SOC. I extrapolated out the data and it'd be right at 700A at <3% SOC and 250kW, but that's a very momentary peak before it quickly decreases and would be requested by the car only under very rare thermal conditions. 650A is more typical for 250kW in a M3/MY and that's only for a few minutes at best.
I think the Plaid pack is only about 15% higher voltage. If the larger CT packs are going to sustain 350kW charging at a voltage similar to Plaid, that would need about 20% higher amperage than M3/MY, hence 800+A. That may be possible with a cable similar in size to the V2 cable, but cooled like V3.
But remember Joules First Law (P=I^2R). If the amperage goes up by 23% [800/650] the thermal cooling requirement goes up by 51% [800^2/650^2]. That's not trivial.
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AlanSubie4Life
Efficiency Obsessed Member
Yeah you are right that we are looking at something like 108-110 series cells based on the data so far. The 25% was based on the old speculation.
So 25% more current, 12% more voltage…
Anyway, to me it seems like 56% more heat should be possible to accommodate…not sure about the existing cables…but I have not had problems with them in hot weather (100 degrees) at 250kW so maybe they have enough margin? Or they can make them slightly heavier, but I do not see a return to the ridiculous V2 cable weight and bulk.
AlanSubie4Life
Efficiency Obsessed Member
Details on the Plaid battery (from the EPA test conducted by Tesla) here:
Model S Plaid Battery EPA Data, 100kWh, Voltages, Precise Efficiency Info
Model S Plaid Battery EPA Data, 100kWh, Voltages, Precise Efficiency Info
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How does Tesla define "fully redesigned"? It seems the car, physically from the outside, is identical to the one that preceded it. In every single possible way. I'd be very wary of Tesla's loosey-goosey use of the term "redesigned". It seems marketing and bull***t have coalesced.
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