Decreasing rated range.

[FredTMC]

Any 60 kWh owners have metrics? For me after almost 3,000 miles our S60's rated range right after charge has decreased from 190 rated to 187 :/ Still on 4.4 as originally delivered.

I have 10k mi on my 60. I'm getting 182 on standard charge with v4.4. It's a little lower than I expected at this amount of miles. I never charge up more than i need. I keep the car at a fairly low SOC. My assumption is that the degradation will slow moving forward.

 

[stopcrazypp]

I'm thinking most of this is battery balancing. Tesla seems to have changed the Model S such that it does not balance as much as the Roadster does during most charging (probably to increase charging efficiency for the EPA rating). The only reliable way so far to force balancing to happen seems to be a 100% charge using 110V.

 

[Btrflyl8e]

I have nearly 3,000 miles on my 60... still charging to 190 rated miles, even now that summer is here.

 

[yobigd20]

Using the REST API, I've been logging the state of the car every 10 minutes since I got it in February.

I've mentioned this in one or two other threads before, but I was told my a lead tech manager this is VERY bad for the battery. By pinging the car every 10 minutes, your car stays fully awake 24/7, a constant drain on the 12V battery, thus causing the main battery and cooling systems to be on 24/7 as well to keep the 12V battery charged. Basically you yourself are speeding up the battery's degradation. I would stop doing this immediately.

 

[Banahogg]

I've mentioned this in one or two other threads before, but I was told my a lead tech manager this is VERY bad for the battery. By pinging the car every 10 minutes, your car stays fully awake 24/7, a constant drain on the 12V battery, thus causing the main battery and cooling systems to be on 24/7 as well to keep the 12V battery charged. Basically you yourself are speeding up the battery's degradation. I would stop doing this immediately.

My vampire drain numbers are exactly in line with what others report.

 

[dsmith2189]

Using the REST API, I've been logging the state of the car every 10 minutes since I got it in February. To figure out how much it's charging to, I grabbed the first data point when the status went from charging to complete and where range mode was false.

View attachment 25551

It was stable for a while, but has been going down significantly since about day 75. A linear fit on the data from [75,150] gives -0.0529667*day+192.8. If that trend continues, I'll be at 70% at the 3 year mark. Hopefully it does level out.

You can't see it on this graph, but in the flat region, the percentage charge reported at completion slowly increased from 91 to 93, which may have been masking any degradation in that region. Hard to say with the data we can get access to...

Edit: I should note I'm at about 5000 miles, though since the odometer isn't in the basic API (only streaming), I haven't been logging it.

with your data, it would be interesting to see when you did your firware updates (and what version) to see if that is being affected.

- - - Updated - - -

4.4 standard charge is 93%, not 85%.

to figure out what my % charge is with a STD charge (Version 4.5 -v1.33.59) I did a full charge to 264 miles, when I do my STD charge I get 232/233.
93% = ~244 miles (about what I had with 4.4, I was getting 242/243)
90% = ~237 miles
88% = ~232 miles (What I get with 4.5)

- - - Updated - - -

I wonder if the reported drops have anything to do with the summer heating ....

In Hawaii temperature is consistent year round. so I don't believe the drops have anything to do with summer.

- - - Updated - - -

My vampire drain numbers are exactly in line with what others report.

I have about a 15 mile per day vampire drain.

 

[EMDoc]

Thanks for the info. Sounds like my situation is similar to yours. Std charge on 4.5 (.54) appears to be approx 88% or so and have 232-235. Climate in SD is relatively stable as well...

with your data, it would be interesting to see when you did your firware updates (and what version) to see if that is being affected.

- - - Updated - - -



to figure out what my % charge is with a STD charge (Version 4.5 -v1.33.59) I did a full charge to 264 miles, when I do my STD charge I get 232/233.
93% = ~244 miles (about what I had with 4.4, I was getting 242/243)
90% = ~237 miles
88% = ~232 miles (What I get with 4.5)

- - - Updated - - -



In Hawaii temperature is consistent year round. so I don't believe the drops have anything to do with summer.

- - - Updated - - -



I have about a 15 mile per day vampire drain.

 

[walla2]

The 232/233 is what I get with the 4.5 1.33.59 at max daily charge (not max charge) on the slider. When I had .54, my max daily was 212 like some others posted. I think there are two reasons for the change from 242ish down to 232.

1. Software changes seem to change the numbers significantly (.54 is the best example)
2. Charge limiter slider going to a lesser % than the standard charge of 4.4.

The change bothers me too, but I believe all of our batteries are all fine.

 

[FredTMC]

I'm thinking most of this is battery balancing. Tesla seems to have changed the Model S such that it does not balance as much as the Roadster does during most charging (probably to increase charging efficiency for the EPA rating). The only reliable way so far to force balancing to happen seems to be a 100% charge using 110V.

Interesting... So, are you saying I should do a full "range" charge using 110v in order to enable battery to fully balance? I'll try it.
Does it matter how low of a state of charge I start from (e.g. Battery nearly empty)?

 

[xray]

I'm at 9200 miles and there has been no change in the standard or range charge capacity.
Standard - 242 rated miles
Range charge - 265-266 rated miles - last range charge yesterday.
Still using version 4.4
Primarily use NEMA 14-50 but occasionally have used Superchargers and 70 and 80 amp HPWC.

 

[aviators99]

I think there are too many variables to draw any conclusions about degradation yet. The displayed range after a charge can be affected by a lot of factors besides actual loss of capacity:

- The reading can fluctuate at the end of a charge and take a while to settle in.

- An out of balance pack will show a lower number, but it can be brought back up when the battery is balanced.

- The algorithm needs to go through a full cycle of the battery (high SOC to low SOC) to recalibrate its estimate of capacity. On the Roadster this needs to be done on a single key turn.

- Charging at lower amps or 120V can show a higher reading (possibly because of better balancing).

- Ambient temperatures can vary the reading. I generally get higher readings in the summer on my Roadster than the winter.

- Changes in the firmware can change the readings. For example the big drop with the lower "standard" charge in 4.5, but more subtle changes in capacity estimates can be made in each firmware release.

What we really need is access to the CAC value (Calculated Amp hour Capacity) on the REST API to get a consistent reading of capacity.

With less than a year on the Model Ss I think it's still to early to see degradation (except maybe on the extremely high mileage cars) and any differences in the estimates are probably noise from other factors.

Tesla tells me that they have confirmed that it's actual degradation for me, and that it is "as expected". This is even though there are plenty of people who are still at 270+ with more miles than I have, while I have lost 15 miles so far.

 

[rlawson4]

I have found that a good slow charge after the car has been driven at least 100 miles helps restore some range. Set the amp to 12 while plugged into a nema 14-50. You will gain 9 miles per hour. This has restored me to 237. I have 16000 miles.

 

[Banahogg]

with your data, it would be interesting to see when you did your firware updates (and what version) to see if that is being affected.

See this post : Decreasing rated range. - Page 2

I have about a 15 mile per day vampire drain.

I'm actually at 8-10 miles of vampire drain.

I'm not too worried about the loss just yet, but I do hope that it slows.

 

[mdh]

Tesla tells me that they have confirmed that it's actual degradation for me, and that it is "as expected". This is even though there are plenty of people who are still at 270+ with more miles than I have, while I have lost 15 miles so far.

I wonder how tesla comfirm's this?

 

[aviators99]

I wonder how tesla comfirm's this?

They looked at the logs from each of my max range charges over time, and checked the battery group statuses.

 

[pfq1982]

Using the REST API, I've been logging the state of the car every 10 minutes since I got it in February. To figure out how much it's charging to, I grabbed the first data point when the status went from charging to complete and where range mode was false.

View attachment 25551

It was stable for a while, but has been going down significantly since about day 75. A linear fit on the data from [75,150] gives -0.0529667*day+192.8. If that trend continues, I'll be at 70% at the 3 year mark. Hopefully it does level out.

You can't see it on this graph, but in the flat region, the percentage charge reported at completion slowly increased from 91 to 93, which may have been masking any degradation in that region. Hard to say with the data we can get access to...

Edit: I should note I'm at about 5000 miles, though since the odometer isn't in the basic API (only streaming), I haven't been logging it.

Banahogg, would your usage of the car permit you to try and recharge fully through a 110V outlet? It would be a great experiment to test the cell rebalancing hypothesis put out there by some of the other forum members...

 

[Banahogg]

Banahogg, would your usage of the car permit you to try and recharge fully through a 110V outlet? It would be a great experiment to test the cell rebalancing hypothesis put out there by some of the other forum members...

I can do a minimum amperage 240V charge pretty easily, which should be equivalent wattage (the battery never sees the AC voltage).

I'm somewhat torn on doing that experiment. Part of me is curious if it works, but part of me just wants to keep watching for a while and see what happens. I'll probably let it go for a month or two longer with just observing.

 

[stopcrazypp]

Interesting... So, are you saying I should do a full "range" charge using 110v in order to enable battery to fully balance? I'll try it.
Does it matter how low of a state of charge I start from (e.g. Battery nearly empty)?

The Roadster people suggest starting from a 20-30% SOC, but this should not be strictly necessary. It may be inconvenient (might take too long, it takes 65 hours to charge from empty on 110V) to start from such a low SOC, so just start at as low as convenient for you.
http://www.teslamotorsclub.com/showthread.php/11451-How-To-Balance-Battery

Basically a 110V charge to 100% and letting it sit plugged in a couple of hours afterwards should force the car to balance the pack. Or you can go with the other suggestions of just dialing down the 240V charge to minimum amperage for equivalent wattage if that's more convenient for you.

Then you can go back to your normal charging routine. You don't have to do this regularly, once or twice a year at most, when you suspect it may be unbalanced. Any range that you "gain" should mostly stay for the subsequent "normal" charge cycles (until eventually it gets unbalanced). There will be some drop from the number you see immediately after the 110V charge (that's the "best case" number), but the number you see in subsequent normal charge cycles after that should be higher than what you originally got, if it's really a balance issue.

 

[William13]

Plug In America has a spread sheet on this topic.
My max was 272 miles consistently until 11,000 miles. Two weeks after 4.5 and some spirited driving it dropped. It is now consistently at 259 miles immediately after filling. 14,500 miles.

 

[mdh]

Plug In America has a spread sheet on this topic.
My max was 272 miles consistently until 11,000 miles. Two weeks after 4.5 and some spirited driving it dropped. It is now consistently at 259 miles immediately after filling. 14,500 miles.

do you think this is degradation or sw changes? I wish TM would clear things up.