According to wk057
Calculate usable battery capacity based on rated miles values
The classic Model S RWD range is calculated using 295 Wh/Mi. Winter is tough on Wh/Mi, mine was definitely way up during the winter months.
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According to wk057
Calculate usable battery capacity based on rated miles values
The classic Model S RWD range is calculated using 295 Wh/Mi. Winter is tough on Wh/Mi, mine was definitely way up during the winter months.
Ya, I've seen Jason's numbers. What I can tell you is that the power usage as reported by the car on the dash differs.
If I consume 295Wh/mi I burn range faster than rated. For my car 273 is about it.
Perhaps the car calculates based on 295 in order to accommodate some overhead and/or the energy reported on the dash excludes some non-locomotive usage.
If I consume 295Wh/mi I burn range faster than rated. For my car 273 is about it.
Perhaps the car calculates based on 295 in order to accommodate some overhead and/or the energy reported on the dash excludes some non-locomotive usage.
Note that there are certain overhead elements in a cell. The center folding line which is a dead space at the center of the cell would be the same for an 18650 and a 2170. So this favors the 2170, i.e. more internal volume efficiency. Also there is less steel casing per volume in the 2170 compared to the 18650. Together these should offer a 2 to 3% improvement in unit capacity irrespective of chemistry or other factors.
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Tesla gets tricky with what they display on the dash. On some vehicles, the nominal energy remaining / nominal full pack yields a different result than what is displayed on the dash. For instance, right now my car shows 69.9% SOC, but looking at CAN data it reports 71.4%. I suspect that this same discrepancy explains why you appear to consume rated miles faster than what you would expect using @wk057 numbers.
I'll just throw out there that I know for a fact the Model 3 is using 2170 cells.
Edit: Oh, I see where the 4416 number came from. Someone is bad at leaking information it seems... lol. It's not cell type, it's cell count. The Model 3 75 kWh pack is 96S46P, so, 4,416 cells.
Edit: Oh, I see where the 4416 number came from. Someone is bad at leaking information it seems... lol. It's not cell type, it's cell count. The Model 3 75 kWh pack is 96S46P, so, 4,416 cells.
LargeHamCollider
Battery cells != scalable
Can you confirm car and driver's quote of Elon that there are 3 modules? I'd guess this would make them 32s46p each?
That would make for some really low voltage in the low range car, I was guessing 96S42P.
No. There are 4 modules of 23, 25, 25, and 23 groups. The lower range version will just have fewer cells in each group, but still ~402V.
LargeHamCollider
Battery cells != scalable
Wow, that is far more cells than I would have guessed; assuming no volumetric energy density improvements compared to the S/X cells, this makes the long range pack 80.0kWh. So guessing the low range pack is 96S32P?
Zaphod
Galaxy President (former)
How long before you do a Model 3 teardown?
Interesting. Why wouldn't they have just gone with 24 groups in all 4 modules?
How long before you do a Model 3 teardown?
How long before someone totals a Model 3 and @wk057 can get one at auction?
What's your take on the high number of cells for the apparent capacity demand based on published range and leaked 237Wh/mi consumption? To me, the capacity seems to have a very significant reserve, or the 2170 cells are a terrible disappointment from a size or density standpoint. Something's up!
All about the range narrative, and packs holding its "new" charge for several years?
Happy to hear about the voltage. Someone earlier kept referencing a spreadsheet they made "calculating" that the voltage was something like 300V, which would have been annoyingly low. And which I found dubious, for a number of reasons.
Why do you say that? The Model S 90kWh pack had 7,104 cells. The Model 3 pack has 4,416 cells. So it has 38% fewer cells, but still has ~90% of the capacity. (So if you account for the capacity difference it takes ~31% fewer 2170 cells than 18650 cells.)
My immediate thought as well. Must be some interesting layout constraint.
This also means BIG modules. A Model S has 16 modules containing 6 groups of 74 cells for a total of 444 18mm diameter cells. A Model 3 would have either 1,058 or 1,150 cells 21mm in diameter.
Because the cross-section of a 21mm cell is already 36% greater. And moreover the cells are 5mm / 7.7% longer as well. Talks by JB and Elon of 10-15% improved density for these 2170's on chemistry alone. Lots of tweets about more energy dense cells in the business.
Recent Tesla 18650's I've seen reported as 12.4-12.67Wh each. If 4416 cells are needed to make the 77kWh or so needed, then they are only 17.4Wh, just 40% more. Without significant reserve in these 3 packs, this could actually be a painful density LOSS.
Either the 2170's are awesome, packing 19.5Wh or so, and Model 3 LR has fewer than 4416 off them. Or they have 4416 and good spare pack capacity above 310 miles. Or, 2170's are just Tesla speak for barely 20 mm thick cells.
Or, these 2170's basically provide general suction of the undesirable kind.
Just as I had speculated -- that the groups (not modules and not the 96s voltage) are smaller on the T3.220. @scaesare
So we have 4s24s46p for the T3.310 and 4s24s32p (or 31p) for the T3.220 - probably in a 24s46p module - i.e. 14 vacant cells slots per group. What I don't understand is why two kind of modules (23s and 25s) instead of one kind (24s)? What is the point of having two different module sizes (or a 25s module with only 23s groups fitted)?
To be exact (2s25s+2s23s)46p for T3.310.
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It's worth nothing that, from the Model 3 press kit, 237 Wh/mi wall-to-wheels is not correct. From the spec sheet, "30 miles of range per hour (240V outlet, 32A)" is 256 Wh/mi wall-to-wheels. So the wall-to-wheels difference vs. the S isn't as great as that calculator led on.
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