90D Range slowly declining

[Beryl]

My 90% is 303 right now. About 5k miles on the car. I don't get anywhere near that in real world driving though

Now I'm beginning to wonder if there is an algorithm problem. Your climate has been colder so that makes 303 even more incredible.

(Still consistently getting 255 @ 90%)

 

[sorka]

My 90% is 303 right now. About 5k miles on the car. I don't get anywhere near that in real world driving though... not even close.

Unless you have a 100D that's ideal and not rated miles.

 

[msnow]

My 90% is 303 right now. About 5k miles on the car. I don't get anywhere near that in real world driving though... not even close.

That is just bizarre.

 

[Naonak]

Unless you have a 100D that's ideal and not rated miles.

You are right... I must have switched it to ideal at some point and never switched it back. Weird. I've switched it back now ... I will check what my 90% is next time I charge. Sorry about that.

 

[cinergi]

holding steady at 254 when warm and 252 when cold. only 3700 miles on the car tho. 6 months.

 

[marin]

The configurator page for the new facelifted 90D now shows 294 total range. This matches up more closely to the 267 @ 90% I was seeing with the newer 90D loner that I had.

So far I've seen the configurator page show the following 90D ranges: 270 + 6%, 288, and now 294.

 

[msnow]

The configurator page for the new facelifted 90D now shows 294 total range. This matches up more closely to the 267 @ 90% I was seeing with the newer 90D loner that I had.

So far I've seen the configurator page show the following 90D ranges: 270 + 6%, 288, and now 294.

After 6 or 7 months my 100% is about 276-278. It should be 286-287. Not sure where they came up with 294 it's the same battery as discussed upthread. The congfigurator just says "range" not "rated range" which is the EPA rating. Just saying range could be "ideal range" or something else.

 

[Boatguy]

The configurator page for the new facelifted 90D now shows 294 total range. This matches up more closely to the 267 @ 90% I was seeing with the newer 90D loner that I had.

So far I've seen the configurator page show the following 90D ranges: 270 + 6%, 288, and now 294.

I took delivery yesterday and this morning my 90% RR was 264.

 

[apacheguy]

Not one person in this thread has access to a CAN logger to read battery energy data?

 

[BertL]

FWIW, I installed firmware 7.1 2.16.17 last evening. It had no effect on Rated Range after my 90% top-off occurred early this morning. My S90D remains at 250-252 miles @ 90% over the last couple months, with temp still having no correlation to the slight variation.

 

[Model S M.D.]

I've got a 90D loaner with 500 miles on the car, consistently getting 265 @ 90%.

 

[msnow]

FWIW, I installed firmware 7.1 2.16.17 last evening. It had no effect on Rated Range after my 90% top-off occurred early this morning. My S90D remains at 250-252 miles @ 90% over the last couple months, with temp still having no correlation to the slight variation.

I may have got an extra mile Rated Range after the update but I also did a trip charge so it could have just rebalanced, more testing needed. I will report back. Currently getting 250-252 with range mode off.

@Model S M.D. you really need to see it after a couple of months to say it's consistent not just a day two.

 

[BertL]

...Currently getting 250-252 with range mode off.

Interesting. As you know, I run with Range Mode ON and have purposely not changed it while trying to figure out what's going on with Rated Range -- so right or wrong, I've always attributed your slightly lower nums than mine being because of that. With our RR@90% now effectively within rounding error difference of one another, perhaps it has nothing to do with Range Mode...

Too much hocus-pocus going on under the covers for my older mind to assess I suppose. I just want my RR to be within a mile or two of what was quoted on the website as RR for the Range Upgrade Option when I purchased my MS, regardless of the whole "it's gonna get worse over time" discussion. Ours were not close on day of delivery, and have remained consistently low -- especially now compared to newer 90's that are lightyears ahead of our RR with IIRC the same battery revisions. Sighhhh. I guess I'm just a difficult customer to please on this subject.

 

[msnow]

Interesting. As you know, I run with Range Mode ON and have purposely not changed it while trying to figure out what's going on with Rated Range -- so right or wrong, I've always attributed your slightly lower nums than mine being because of that. With our RR@90% now effectively within rounding error difference of one another, perhaps it has nothing to do with Range Mode...

Too much hocus-pocus going on under the covers for my older mind to assess I suppose. I just want my RR to be within a mile or two of what was quoted on the website as RR for the Range Upgrade Option when I purchased my MS, regardless of the whole "it's gonna get worse over time" discussion. Ours were not close on day of delivery, and have remained consistently low -- especially now compared to newer 90's that are lightyears ahead of our RR with IIRC the same battery revisions. Sighhhh. I guess I'm just a difficult customer to please on this subject.

Agree, if I flip Range Mode to "on" I either get an additional mile RR or no change.

 

[Ingineer]

Data Point: I just did a 100% charge in my P90D and it's showing 267.4 rated miles, The CAC (Calculated Amp-Hour Capacity) is 239Ah. I am running current software (2.16.17).

Here are my string voltages in case anyone is curious: 4.192,4.190,4.189,4.189,4.188,4.192,4.195,4.194,4.194,4.194,4.194,4.196,4.194,4.194,4.191,4.191,4.194,4.195,4.196,4.194,4.195,4.195,4.194,4.198,4.192,4.191,4.191,4.191,4.191,4.192,4.196,4.196,4.193,4.196,4.195,4.196,4.193,4.191,4.189,4.188,4.189,4.193,4.195,4.194,4.194,4.194,4.194,4.195,4.195,4.194,4.194,4.194,4.193,4.195,4.194,4.193,4.192,4.193,4.192,4.194,4.193,4.193,4.193,4.191,4.192,4.193,4.196,4.194,4.194,4.194,4.194,4.194,4.196,4.197,4.197,4.196,4.196,4.197,4.195,4.195,4.195,4.194,4.194,4.195,4.196,4.194,4.194,4.194,4.194,4.195,4.193,4.192,4.192,4.192,4.192,4.192

And I have access to all data from the BMS and can log any CAN data as well.

 

[BertL]

Simply for comparison, my non-P S90D last charged to 100% on 3/20 and showed 280 Rated Range miles (251 @ 90%).

 

[msnow]

Simply for comparison, my non-P S90D last charged to 100% on 3/20 and showed 280 Rated Range miles (251 @ 90%).

Did 100% last night too. Mine is also 280 rated miles with Range Mode off.

 

[apacheguy]

@Ingineer - How does CAC translate to the full pack energy reported by the BMS? In other words, what is the voltage multiplier to get Ah -> kWh?

 

[MarcG]

@Ingineer - How does CAC translate to the full pack energy reported by the BMS? In other words, what is the voltage multiplier to get Ah -> kWh?

From my understanding of the 85 kWh battery, the pack is arranged in 96 series modules of 74 parallel cells, so you add up the voltages of all the 96 modules then multiply the resulting total voltage by the Ah capacity to get Wh capacity (divide by 1000 to get kWh, obviously).

In the example Ingineer provides, if you add up all his modules' voltages, you get a total pack voltage of 402.578 V. Multiply that by 239 Ah and you get 96,216 Wh or 96.2 kWh. Note that there are resistive losses so that's not necessarily the real pack's capacity.

 

[Ingineer]

There is no fixed voltage. As the pack discharges, the voltage falls. This is why battery manufacturers use amp-hours instead of watt-hours to rate thier products. The formula to correlate the two is going to be complex. As a rule of thumb you can use the nominal voltage of the cells. Sometimes it works out better to use the average between full and low voltage cut off too, but this is only going to be a rough estimate without plotting dVdT.

What you can do though is compare the CAC between an 85 and a 90 since it appears the voltages are almost identical.

My Wife's P85D with about 15k miles is reading a CAC of 226Ah and my P90D pack with about 4k miles is now reading 240Ah. (It appears to have risen one amp hour) This car also just got the 2.17.37 software.

If we extrapolate using 375 volts as the nominal, we get exactly 90kWh on my 90 pack, and 84.75kWh on my Wife's 85.
If we do it with 370v, we then get 88.8kWh and 83.62kWh respectively.
360v is 86.4kWh / 81.36kWh. This seems more in line with what people are seeing real-world. That would be about 276 / 260 miles if we assume an average of about 313Wh/Mi.

Earlier tonight my 90% charge on the 90 is showing 396 volts with an expected energy of 72.5kWh (BMS_E_Expect) and an Ideal of 74.8kWh (BMS_E_Ideal). So 100% on it should be about 80.6kWh Expected and 83.11kWh if you take stock in the BMS numbers. Of course, the watt-hour to amp-hour conversion is not going to be linear because the dV-dT discharge curve is also not linear on most Lithium cells, it's sort of an S curve with larger swings at each end.

Next time I do a 100% charge, I'll note the figures again.