2% Battery Degradation in 1 Month

[foodgoeshere]

First post here so please be nice.

Since taking delivery of my Model 3, I've set the battery charging limit to 90% and was consistently getting 279-281 miles when charged "full". Just last week, I've noticed that 90% only charges me up to 274 miles. I've had my Model 3 for a month and have 1,900 miles on the odometer. I've only been charging with Level 2 chargers and 2 instances of 15 minute supercharging. Should this be cause for concern?

 

[SSedan]

It isn't an accurate number don't worry about it.

 

[foodgoeshere]

It isn't an accurate number don't worry about it.

Cool, thanks.

 

[TexasEV]

As noted above, it’s an estimate as battery state of charge can not be measured directly. Also it’s expected for a battery to lose capacity in the first few months, then it settles down to less than 1% per year. My Model S 60 lost 4 miles of range in the first few months, then 1-2 miles/ year after that.

 

[Electroman]

@azred: what is so funny about that concern from OP ?

Just a bit of history here. This is how it all started in the Leaf forums in 2012.

• First one guy reported degradation and others laughed.
• Then a few others expressed similar sentiments, and the battery experts there all chimed in with different convoluted explanations on battery balancing, ambient temperature, cathode, anode, this and that - all of that amounted to "The driver is at fault and he is not driving with the right set of pants".
• As the complainers got a bit vocal, the defenders were getting annoyed. I remember attending an EV gathering here in Dallas, and a few members expressed their frustration about the unnecessary noise in the forums about degradation when that is really a non-issue.
• And then the realization that heat is indeed having an impact, but it can be mitigated by doing this and that.
• Finally the law suit.

M3 new format cells have still not proven in the wild. We haven't gone through one summer yet. Don't expect the success of SX batteries to translate into M3 yet. So the jury on battery degradation on M3s is still out.

 

[Fusion]

I know they changed the size, but did they also change the chemistry of the battery??

 

[emlombardo]

I've not noticed any meaningful change. I have around 2,100 miles on the car and charged to 90% yesterday and it reported 279 miles. If I recall when it was new it was always 279 / 280.

 

[wwu123]

Our Model S did follow a rather steady decline over the first year, currently down about 5.5% in rated range, but we expect it to flatten out as is typical of Model S owners.

Our Model 3 after two months does show a different behavior so far, it's been remarkably flat, but within a certain variance. We have the limit set at the somewhat odd 83% that we never bothered to change the setting, but some weeks that equates to 255 miles, other weeks it jumps up to 258, then back down to 255, then back up to 258 at present.

You're observing a drop of 5 miles in the past week, but that could be as little as two charge cycles; too few observations and too short to know whether it will settle there, drop another 5 miles next week, or jump back up 5 miles next week. I wouldn't worry just yet.

 

[foodgoeshere]

Our Model S did follow a rather steady decline over the first year, currently down about 5.5% in rated range, but we expect it to flatten out as is typical of Model S owners.

Our Model 3 after two months does show a different behavior so far, it's been remarkably flat, but within a certain variance. We have the limit set at the somewhat odd 83% that we never bothered to change the setting, but some weeks that equates to 255 miles, other weeks it jumps up to 258, then back down to 255, then back up to 258 at present.

You're observing a drop of 5 miles in the past week, but that could be as little as two charge cycles; too few observations and too short to know whether it will settle there, drop another 5 miles next week, or jump back up 5 miles next week. I wouldn't worry just yet.

Thanks, I should have noted in my OP that I charge it daily on M-F to 90%. I'll monitor as I keep charging and see if there are any fluctuations.

 

[TexasTeslaRacing]

Like others have said, don’t worry about it. Mine is always between 274 and 281. Seems to change to a number between those every other week. My MS and MX don’t vary as much. They seem more stable when estimating the range of the car @ 90%.

 

[jamnmon66]

I think it's more than reasonable to pay attention to this but there's a lot of variables in this number (AFAIK). So more data over a longer time period is needed to draw any conclusions.

I've watched the lecture from that Tesla battery expert in Canada &, if I remember correctly, it's normal for a new battery to loose a few percent in the first year or so. Then it flattens out & degrades very slowly. I can't remember his name. Maybe someone on a computer could post the link (I'm on my phone).

Also, from that lecture, not every battery performs exactly the same, even on the fancy testing apparatus that they developed. Some variations are expected.

 

[dhrivnak]

First post here so please be nice.

Since taking delivery of my Model 3, I've set the battery charging limit to 90% and was consistently getting 279-281 miles when charged "full". Just last week, I've noticed that 90% only charges me up to 274 miles. I've had my Model 3 for a month and have 1,900 miles on the odometer. I've only been charging with Level 2 chargers and 2 instances of 15 minute supercharging. Should this be cause for concern?

I have seen the SAME thing as I have had my car 4 weeks and 2,200 miles.

 

[Uncle Paul]

I believe that your range estimates is adjusted by your driving style. Lots of high speed or agressive driving will result in a lower range display. Conservative driving at lower speeds, will give higher estimated range.

 

[Pkmmte]

I've had my Model 3 for a month now and my battery actually had the opposite effect right after a mini road trip when I charged it to 100% (313 miles) for the first time. I've only ever charged it using superchargers from 10% - 20% to 90% and the range was always either 278 or 279 miles. After the road trip, I charged it to 90% as usual and saw 282 miles instead.

Maybe it recalibrated?

 

[goto10]

I believe that your range estimates is adjusted by your driving style. Lots of high speed or agressive driving will result in a lower range display. Conservative driving at lower speeds, will give higher estimated range.

This is not correct. Some EVs do estimate range based on driving habits but Tesla does not.

 

[Electroman]

Nissan does it in its Leaf. Stupid way of estimating range.

 

[TexasEV]

I believe that your range estimates is adjusted by your driving style. Lots of high speed or agressive driving will result in a lower range display. Conservative driving at lower speeds, will give higher estimated range.

NO, NO, A THOUSAND TIMES NO. How many times do we have to explain this is not what rated range means. Read any of the thousands of posts explaining this. Rated range is the range on the EPA test cycle. Period. Full stop.

 

[gregincal]

The other thing to check is to switch your display to battery % and see what it says. I always have my display set that way, and when I come out in the morning I find the car will show between 88% and 90%, even though the charge limit never changes from 90%. My guess is a cold battery affecting the calculation.

 

[keydiver]

^^^THIS^^^
I have found that unless you are checking the rated mileage right after the charging has finished, you are not comparing apples-to-apples. Because of phantom/vampire losses, on my Model S I see only 88-89% the next morning. At 90% you should see 279, but 88% is only 273. Charging to 90% is a once and done operation, it will not continue to top off until you unplug. So, what you might be seeing is simply a lower state of charge after the car has sat for a while. I would only be concerned if the trend continues month after month.
BTW, comparing this to the Leaf fiasco probably isn't fair, as Nissan's main issue is no TMS, and has little to do with the chemistry or cell size. I'm sure that Dr Dahl has thoroughly tested the 2170 cells before they implemented them into the Model 3, whereas my Leaf's second battery ("Lizard") degraded just as quickly in the Florida heat. So much for improved chemistry.

 

[techmaven]

This is an issue worth tracking and there is absolutely fine to ask the question.

@foodgoeshere, the only accurate way to get a reading on the battery pack is to run it down below 20 miles of range, then charge it all the way back up. And then see. And if your battery pack is very far out of balance, one might have to do that more than once. But it probably isn't worth doing that on a regular basis. So unless it really bothers you, I'd let it go for now unless the drop really gets to a point where it bugs you.