Serious Tesla Model 3 Battery Degradation

Tesla Model 3 Charging Screen

Before I purchased my Tesla Model 3, I did a good amount of research on what the expected battery degradation would look like. While how quickly a battery degrades comes down to a number of factors, a number of sources (Car & Driver, Find My Electric) pegs this loss (on average) in the neighborhood of 5% every 100,000 miles. Tesla itself claims that after 200,000 miles driven, their battery packs loose less than 10% of their capacity.

I’ve owned my Tesla Model 3 Long Range for nearly 10 months as I write this. I have put on about 13,700 miles on the car in that time. I’ve follow Teslas advice and charge it nightly to between 80-90% (depending on what is happening the next day). I only charge it to 100% before a trip that would require at least one supercharge. All of my charging at home since February is performed using a

. It charges at a rate of about 50 miles/hour. Most of my charging is done overnight starting around 2AM. Upon installation of the Wall Charger, Georgia Power gave me a low super off-peak hour rate of 1 cent/kwh.

I use the stock 18″ wheels with the Aerodyne covers. I generally drive on either Chill or Standard Mode, and try to keep each drive at or under 250kw/h expenditure.

I don’t leave Sentry Mode running on the car since reading this article. For the first few months of ownership, I did leave Sentry Mode on when I left the house, but haven’t since about May.

As for long trips, I’ve taken 3 trips in my Model 3 that have required supercharging stops. Those trip lengths have been (in no particular order):

  • Two trips to Orlando (453 miles each way)
  • One trip to New Hampshire (1067 miles each way)

As for number of supercharging stops I’ve made – 22 to date. The trip to Orlando was responsible for 8 of them, the trip to New Hampshire was responsible for 14 of them. So you can see that Supercharging is not part of my normal charging behavior, unless I’m road tripping and can’t avoid it.

Starting back in May, I noticed my capacity dropping. I didn’t think much of it, because, after all, some battery degradation is inevitable. When leaving for my trip to New Hampshire though, and charging to 100%, I noticed my top range had dropped significantly. 100% of charge was now rated at 321 miles. This is 35 miles less than the range when I took ownership of the car – a full 10%. In 8 months of ownership. So I started to become concerned.

During my service appointment where Tesla cleaned my air coils to remove the odor in the air conditioning, I spoke with the technician about this. He stated the range was most likely fine, and that it was a battery calibration issue. His advice was to stop plugging in nightly and charging to 80/90%, and instead let the battery discharge to between 30-40% before recharging. He stated I should do this for a month, and during that time, the computer would recalibrate where the bottom and top of range was, and I should get my missing range back.

It’s been a month since I started doing this, and after checking my range using the Stats app, this it what it looks like now:

Odometer (Miles)Range at 100% SoC
Data captured using the Stats app for iPhone

So after trying to ‘recalibrate’ the computer to properly show my range for a month, I’ve got… less range than when I started. In 10 months of ownership I’ve lost 10% of range. Ugh.

Now, Tesla warranties their battery for the Model 3 Long Range here in the USA for 8 years/120,000 miles and guarantees it will still retain 70% of its charge. If my issue is truly battery degradation and not a mis-calibration, I’m already 1/3 of the way to that goal in only 10 months.

I’ve got a service appointment this week for tire rotation. I’m going to follow up with that service technician and see what the next steps are.

The Model 3 LR has been hands down my favorite vehicle I’ve owned in the last 30 years. That said, range loss on this scale is deeply concerning. I’ll post an update after I hear from Tesla on what the next steps are.