Lost ~6 to 8 Rated Miles after 4500 miles road trip

[geoc]

Did a 4500 miles road trip end of June through some of the hottest places in the country (UT, AZ, LV and Death Valley).
Whole trip took ~18 days and my goodness the trip was just about as perfect as it can be except:

a week or so in started noticing range loss... Hoping someone can help me troubleshoot:

2015 S90D

Range has been steady at ~277RM for 1.5 years (~20000 miles ODO between 10000 to 30000)
Never had warning about diminished cooling or driving like a mad man doing triple digits going uphill, etc.

Of course the trip was mostly done with superchargers, fans were blowing like crazy during supercharging, never saw any warning msgs.



Initially thought it was a variation under extreme heat (110F+) but seems like the range has not returned.

I have made an appt with SC to look at a few other things and am going to ask about the lost in range, does SC care about data reported through teslafi? or would SC discount teslafi as a third-party app and ignore all of the logs?

Frequent roadtrippers: after initial 10/15k miles of range loss, is it common to lose that many miles in a relatively short time with daily superchargings?

does this qualify for "Sudden Battery Degradation"?

THANKS everyone in advance for helping and can pull detailed tesalfi logs if they would be helpful.

 

[jelloslug]

I look some long trips back to back recently and lost 2 miles of range. It has slowly come back on its own now though.

 

[Tesomega]

I have made an appt with SC to look at a few other things and am going to ask about the lost in range, does SC care about data reported through teslafi? or would SC discount teslafi as a third-party app and ignore all of the logs?

They don't seem to care. I reported range loss issues and they said that they ran through their battery tests and comparison across fleet data and they dont see any issues. I read tesla does not warrant battery degradation so we might not be able to do much here.

 

[P85_DA]

This is not “battery degradation” at best just rebalance your pack

 

[Tesomega]

rebalance your pack

My understanding is that this is not required anymore atleast for the newer models >AP1 or the BMS takes care of this. Is there a specific way to force this?

 

[P85_DA]

My understanding is that this is not required anymore atleast for the newer models >AP1 or the BMS takes care of this. Is there a specific way to force this?

Maybe the BMs does ..but in past I would charge close to 100 than drain down to single digits ...after 3 Tesla’s I don’t really care about what my screen shows I just set it to percent ..with an 8 year battery warranty this doesn’t really bother me ...personally I wouldn’t clog a SC to look at something like this

 

[croman]

8 miles of rated range is a lot to lose. 2-3 sounds like normal variation but >5miles is concerning.

 

[P85_DA]

Plenty of threads on this ...IMO this is not “lost” range ...the OP hasn’t stated if he tried any balancing etc ...this is not even a 10% degradation over original rated range ..

 

[Electric700]

Maybe the BMs does ..but in past I would charge close to 100 than drain down to single digits ...after 3 Tesla’s I don’t really care about what my screen shows I just set it to percent ..with an 8 year battery warranty this doesn’t really bother me ...personally I wouldn’t clog a SC to look at something like this

Generally once a year I will charge to 100% then drive within a half hour after the charge has completed. This will definitely balance the battery. I generally charge well before the car gets to a 5% state of charge, even after balancing the battery. Others have said charging to a slightly lower charge state such as 95% will also allow for battery balancing to be done by the time charging completes.

Also, I understand the Rated range calculation uses the EPA test results.

 

[geoc]

Thanks for the input. i have driven it down to 0 RM (probably still have a few miles to go as power output was barely limited ~200kW)

charged back to 90% - 245 (should be 250)

then something strange happened:

the following morning, after driving to work, it had used a lot less energy than usual
regen was somewhat limited for the first few miles, probably meaning BMS has overcharged the pack to >90%

and the idling afterwards was even more unusual.

i thought the car has "found" the 8 miles lost somewhere on the road trip...
as the car was driven back home, before recharging takes place the 100% guesstimate went back to 277.5 RM
(233.14/.84 = 277.5)

then as i started charging i think there is again the % and RM mis-match

Somehow
at 84%, 100% was estimated to have 277.1
at 87% ~ 274.8
at 90% ~ 272.5
do i just have a super out of blanced pack?
do i have to charge it ABOVE 90% and leave it there for a few hours before balancing will take place?

am i seeing actual deterioration of the pack because of the daily supercharging during the trip or is it just a more accurate guess by BMS WRT energy available in the pack?

 

[TexasEV]

You’re reading way to much into this. The SOC can’t be measured directly, it’s estimated by an algorithm that may be more or less accurate depending on recent charging and driving. A few miles one way or the other doesn’t mean anything. Reporting range in tenths of a mile is particularly stupid. Didn’t anyone learn about “significant figures” in high school?

You may want to delete TeslaFi, stop obsessing over the battery, and just enjoy your car.