2017 Model S 100D battery behavior after charge

[Gray468]

June 2017 Model S 100D. Bought new June 2017. Now 54,785 miles. I generally keep the charge between 50 and 70% unless on a road trip… then 90%. Every 3 months or so, I charge to 100% and drive a long distance right away. Supercharger for about 60% of the time, rest using dryer outlet to get about 17 mi/hr.

In last 6 months noticed that if I charge at home or at a supercharger, an hour or so after cutting the charge, the battery reads 8-12 miles higher, sitting idle. Today, I supercharged to 90% which is 294 miles for my car….about 97.5% of new… so pretty remarkable. Parked, went into COSTCO (same lot) and car read 306 miles. Drove home, a couple miles, now reading 303 miles. So the “additional” miles appears to be real.

Questions:
Anyone else seeing this behavior?
Is this a red flag on battery health?

FYI, I am enrolled in Recurrent which has sent me a monthly battery health check report for the last 14 months. Consistently rated my range as “higher” than the fleet average. I suspect if you account for the type of driving, location, Ave temperature (I am in Southern California) I would be closer to average.

Welcome comments or pointing me to threads that address my questions. Thanks!

 

[Gray468]

June 2017 Model S 100D. Bought new June 2017. Now 54,785 miles. I generally keep the charge between 50 and 70% unless on a road trip… then 90%. Every 3 months or so, I charge to 100% and drive a long distance right away. Supercharger for about 60% of the time, rest using dryer outlet to get about 17 mi/hr.

In last 6 months noticed that if I charge at home or at a supercharger, an hour or so after cutting the charge, the battery reads 8-12 miles higher, sitting idle. Today, I supercharged to 90% which is 294 miles for my car….about 97.5% of new… so pretty remarkable. Parked, went into COSTCO (same lot) and car read 306 miles. Drove home, a couple miles, now reading 303 miles. So the “additional” miles appears to be real.

Questions:
Anyone else seeing this behavior?
Is this a red flag on battery health?

FYI, I am enrolled in Recurrent which has sent me a monthly battery health check report for the last 14 months. Consistently rated my range as “higher” than the fleet average. I suspect if you account for the type of driving, location, Ave temperature (I am in Southern California) I would be closer to average.

Welcome comments or pointing me to threads that address my questions. Thanks!

I got through to Tesla. They considered the issue unusual, saw the behavior in the logs and did some remote diagnostics. They claim all indications are that the battery is very healthy for its age and use. 4% above average. They did not understand my question: what percentile would that be? They seemed to think 4% above average was a lot. But it’s clear they did not know what the reading actually meant. It does, however, track to what the Recurrent monthlies are reporting.

Their explanation was that the car recalculated range and that is all that is happening. I had suspected as much and have been stopping the charge 10-15 miles before my target level.

I know there are plenty of other threads that discuss the need to periodically recalibrate the on board measuring by allowing the car to sit at a relatively low (30%?) charge for a few hours and do that every day for a week or two to improve the range reporting. I might try that.

Still looking forward to hearing if anyone else has had this experience.

 

[ucmndd]

There have been many threads recently describing some version of this phenomenon in recent firmwares. It seems harmless.

Battery level decrease and increase while parked

Battery level of my S 90D 2016 usually decrease few % per day, unless it passes 12%, then decreasing 1% per hour until 5% while parked. Then charging until 80%, charching stopped and next hours the level increase until 84%. Anybody has explanation for this phenomenon?

teslamotorsclub.com

 

[Gray468]

There have been many threads recently describing some version of this phenomenon in recent firmwares. It seems harmless.

Battery level decrease and increase while parked

Battery level of my S 90D 2016 usually decrease few % per day, unless it passes 12%, then decreasing 1% per hour until 5% while parked. Then charging until 80%, charching stopped and next hours the level increase until 84%. Anybody has explanation for this phenomenon?

teslamotorsclub.com

Thanks… the referenced thread seems focused on charging behavior when allowing the battery to go below 10 or 15 %. Similar observation that the battery SOC “increases” after charging stops. I am charging from 50 or 60%. But now that I think of it, the deeper the discharge (meaning the longer I am on charge), the greater the offset after charge.

Thanks

 

[pacman3000]

It's common for the BMS to recalibrate, since it's just a projection based on usage. Remember that temperature plays a pretty significant role in range, so that could also be playing a part in your new readings.

 

[Gray468]

It's common for the BMS to recalibrate, since it's just a projection based on usage. Remember that temperature plays a pretty significant role in range, so that could also be playing a part in your new readings.

Temperature! Yes! That makes a lot of sense. I have had the car almost 5 years and it never did this till the last 8 months or so. I remember there was an update that mentioned improved range estimates, in part, due to compensating for temperature.

Thanks!

 

[Tesomega]

Its all part of Tesla gimmicks on "Range", like some previous references this has something to do with recent software updates..