Low extrapolated range after charge: when is it an issue?

[WattsHappening]

Hi all,

I get there are variances and we can also expect a small decrease in full range over time. 310 miles of range can be 308 or 305. The question is at what point is it an issue that should be addressed?

My AWD has always shown less range than expected. When I charge to 70%, I get 201 miles of range. This implies a range of 287 miles when fully charged. When I charge to 65%, it's 188 miles (implies 289 at 100%). I've had it for a couple of months and have just under 2,000 miles. I've tried to reset the range by filling up to 95%, then driving it down to 10% and recharging. That didn't have a meaningful change in numbers.

We also have a RWD that charges to expected range (216-218 when charging to 70% and 247-250 when charging to 80%).

Big enough of an issue to take it in to SC?

TIA

 

[TexasEV]

No. Start charging to 90% routinely and you’ll see the range increase. The algorithm that estimates battery state of charge isn’t as accurate if you’re typically charging to 70%. You don’t need to baby the battery with lower states of charge. Model S experience shows it does just fine over the years at 90% always.

 

[Eno Deb]

I wouldn't worry about it. It's obvious that the batteries aren't actually degrading, there are just some issues with the range estimation algorithm. Given that this seems to mostly affect AWD cars, my guess is that Tesla still needs to fine tune the algorithm for the dual-motor drivetrain. I think it is best to keep cycling the battery in a medium state of charge range according to your daily needs, knowing that the full range is available when you need it regardless of the estimator. Tesla will probably improve the range estimator via firmware update at some point.

Note that something very similar happened with the Model S in its early days. Here's a comment by Tesla's Jerome Guillen from 2014 that sounds very familiar in hindsight:

A Senior Tesla Executive's Comforting Answer to Concerns Re: "Loss of Range" | Tesla

Some excerpts:

[...] The range estimate displayed in the vehicle is based on several different factors. One important factor is the battery's actual capacity at a given point in its life. This is the amount of energy the battery can hold when fully charged. Since battery capacity cannot be measured without fully charging and discharging the battery, this value is calculated in software. We have found that in cases where the battery is consistently charged to a lower state of charge- between 60-80% -capacity estimation becomes less accurate and tends to underestimate the true capacity of the battery. The result is an incorrect reduction in the displayed range estimate. This does not affect the true range of the vehicle, as the end-of-drive conditions are based on real-time battery measurements of reducing battery power rather than software estimates.
[...]
The inaccuracy of the capacity algorithm will show up in any Model S that is regularly charged under the conditions mentioned above (it seems it is the case for your Model S). We will develop and implement a firmware updates in the coming weeks (timing TBD) to address the concern you outlined. That being said, the amount of actual energy stored in the battery has not changed.
[...]

 

[Dannno]

Hi all,

I get there are variances and we can also expect a small decrease in full range over time. 310 miles of range can be 308 or 305. The question is at what point is it an issue that should be addressed?

My AWD has always shown less range than expected. When I charge to 70%, I get 201 miles of range. This implies a range of 287 miles when fully charged. When I charge to 65%, it's 188 miles (implies 289 at 100%). I've had it for a couple of months and have just under 2,000 miles. I've tried to reset the range by filling up to 95%, then driving it down to 10% and recharging. That didn't have a meaningful change in numbers.

We also have a RWD that charges to expected range (216-218 when charging to 70% and 247-250 when charging to 80%).

Big enough of an issue to take it in to SC?

TIA

Check out this thread: Model 3 Performance Battery Degradation One Month (Story)

We are actively trying to answer this very question. Interesting to see it may not only be P cars.

 

[WattsHappening]

Thanks guys.

@Danno, ya, I've read the entire thread. Many of the posts are very similar to my experience.

I'll try charging to 90% for a while and see how that affects it. I'll report back here or in the longer thread.

Thanks again.