Model 3 SR+ LFP Battery Range, Degradation, etc Discussion

[tgrobbo]

I had the same thought, so I ran the battery health test in service mode yesterday. The results showed battery health at 92%, but the estimated range is still 227 miles. That math doesn’t add up, right (I started at 253, so 92% should be 232)?

Most tests I’ve seen for LFP cars show more degradation than the loss of indicated range - for high mileage cars the test shows a LOT more degradation than the range loss indicates. It’s hard to know which measure to trust.

 

[karlos22]

Have to turn that option on.

Not available where i live. Thankfully I just moved to a warmer climate where it is less of a problem

 

[AlanSubie4Life]

Not available where i live. Thankfully I just moved to a warmer climate where it is less of a problem

Interesting. Wonder why not?

 

[Max Spaghetti]

LFP cuts regen a LOT just fyi. Head down any half decent hill and the little green brake disk comes on, especially in cold weather. I assume it does start to blend in the brakes, but you can feel the car suddenly speed up when it reduces regen. It’s actually pretty annoying.

Preconditioning is everything with LFP in cold weather. I have only been watching battery temps recently since I have S3XY commander, and have been surprised with what I have seen.

It really likes the battery up around 20C for decent regen (60kW) and 22C to get to max regen (85kW). It takes about 3 minutes of battery warming for every 1C temperature rise, so at least an hour to get from 0C to 20C. So either use the departure preconditioning setting to let it work it out itself, or manually turn on climate an hour before departure (seems to do the same thing).

I haven't done any significant continual descents in cold weather so I haven't seen what you are describing (regen reducing) - it would be interesting to see if the battery is cooling down or just getting to a high SOC which also reduces regen.

 

[AAKEE]

Interesting. Wonder why not?

We do not have that option either.

Some kind of regulation probably, I do not know more than that.

 

[AlanSubie4Life]

We do not have that option either.

Some kind of regulation probably, I do not know more than that.

Definitely one of the better enhancements over the years; makes driving much more consistent at a high SOC. Though I will disable it just for the challenge on occasion. For the wider audience of mainstream drivers, this consistency is probably also safer.

 

[tgrobbo]

Preconditioning is everything with LFP in cold weather. I have only been watching battery temps recently since I have S3XY commander, and have been surprised with what I have seen.

It really likes the battery up around 20C for decent regen (60kW) and 22C to get to max regen (85kW). It takes about 3 minutes of battery warming for every 1C temperature rise, so at least an hour to get from 0C to 20C. So either use the departure preconditioning setting to let it work it out itself, or manually turn on climate an hour before departure (seems to do the same thing).

I haven't done any significant continual descents in cold weather so I haven't seen what you are describing (regen reducing) - it would be interesting to see if the battery is cooling down or just getting to a high SOC which also reduces regen.

I think it just doesn’t like too much rapid charging at any temp. Regen is a lot of charge for the poor little LFP pack. We get reduced regen in summer on big hills after an hour of driving. But yeah it probably is much better with a warmer battery for sure.

 

[tgrobbo]

I’ve always found it amazing that an LFP car with 250,000km shows the same displayed range as a car of the same age that’s done 25,000km - that’s ten times as many charge cycles (60 v’s 600 approx) and no difference in capacity loss. Basically it’s as if there is no cyclic aging at all, just calendar aging. Even more curious is when the 250,000km car does a battery test and it shows 12% capacity loss, not the 5% loss indicated by the displayed range. At first I suspected the range reduction was being calculated on time only, but now I suspect that an extra 540 cycles is not significant enough for it to affect an LFP battery that much when it’s only a few years old. I also suspect the battery test is not accurate for LFP cars.

 

[AAKEE]

I’ve always found it amazing that an LFP car with 250,000km shows the same displayed range as a car of the same age that’s done 25,000km - that’s ten times as many charge cycles (60 v’s 600 approx) and no difference in capacity loss.

Cyclic aging with partial discharging (not very big DoD) will have a appearent aging close to NIL.

Basically it’s as if there is no cyclic aging at all, just calendar aging. Even more curious is when the 250,000km car does a battery test and it shows 12% capacity loss, not the 5% loss indicated by the displayed range.

We did guess very early after the LFP’s was introduced that the BMS might not being able to track the capacity very well, and that the degradation we see could be a calculated from calendar aging (of course also cyclic, but it wouldmbe very little).

If you can not measure the SOC very precise the BMS capacity estimate is hard.

 

[eevee-fan]

Cyclic aging with partial discharging (not very big DoD) will have a appearent aging close to NIL.

We did guess very early after the LFP’s was introduced that the BMS might not being able to track the capacity very well, and that the degradation we see could be a calculated from calendar aging (of course also cyclic, but it wouldmbe very little).

If you can not measure the SOC very precise the BMS capacity estimate is hard.

It takes a deep charge/discharge cycle to know for sure. Voltage variance is measurable at the ends.

 

[mg985]

My 2019 Standard Range Plus has only 8,000 miles on it...I bought it new in 2019, and I've typically driven it only a few times a year.

When I charge it to 90%, it shows a range of 200 miles now. I think it used to show 220-225 miles or so.

Is there a way to check when this performance degraded exactly? Is this within the range at which Tesla will actually investigate this as a service issue or am I out of luck?

 

[AAKEE]

My 2019 Standard Range Plus has only 8,000 miles on it...I bought it new in 2019, and I've typically driven it only a few times a year.

When I charge it to 90%, it shows a range of 200 miles now. I think it used to show 220-225 miles or so.

Is there a way to check when this performance degraded exactly? Is this within the range at which Tesla will actually investigate this as a service issue or am I out of luck?

Use the energy graph, get these values on the same picture and post here, and we will do the math for you.
The setting down right must be normal range, and the state of charge not too low (causes rounding errors), > 50% is good.

 

[AlanSubie4Life]

My 2019 Standard Range Plus has only 8,000 miles on it...I bought it new in 2019, and I've typically driven it only a few times a year.

When I charge it to 90%, it shows a range of 200 miles now. I think it used to show 220-225 miles or so.

Is there a way to check when this performance degraded exactly? Is this within the range at which Tesla will actually investigate this as a service issue or am I out of luck?

This it is pretty common for these vehicles to have a little higher capacity loss. Not sure why.

I believe 2019 was 240miles when new which was about 52.5kWh.

[EDIT:] You're at 200@90%, so 222mi

So you would be around 92.5%, 48.5kWh. This is really great and normal.

Use the energy screen method suggested above. That will give you a good estimate. It should match this roughly.

[END EDIT]

 

[AAKEE]

This it is pretty common for these vehicles to have a little higher capacity loss. Not sure why.

I believe 2019 was 240miles when new which was about 52.5kWh.

So you would be around 83%, 44kWh. This is higher than I would generally expect. But warranty must be much worse.

Use the energy screen method suggested above. That will give you a good estimate.

You bet me on it

200mi@90% would be ~ 222 at 100%
I see around 48.6kWh, doing a approx math…?

 

[3sr+buyer]

This it is pretty common for these vehicles to have a little higher capacity loss. Not sure why.

I believe 2019 was 240miles when new which was about 52.5kWh.

So you would be around 83%, 44kWh. This is higher than I would generally expect.

At less than 2,000 miles per year, perhaps the car spent a lot of time parked at a high state of charge (>55% for an NCA battery like a 2019 SR+ has)? I.e. if the customer habitually charged it every day to 80% and drove <10 miles per day so that the car normally does not get below about 75%, then the battery would have been in the higher degradation state-of-charge range nearly all of the time.

If in a hot weather area, that could also lead to greater capacity loss.

 

[AlanSubie4Life]

You bet me on it

200mi@90% would be ~ 222 at 100%
I see around 48.6kWh, doing a approx math…?

Sorry yeah, misread...will correct the post.

a hot weather area, that could also lead to greater capacity los

I just screwed up reading quickly. This car is fine, doing great actually.

There have been reports of ones at 200 miles, though. From Florida. Posted elsewhere here with vehicles just a year or two old.

 

[AAKEE]

My 2019 Standard Range Plus has only 8,000 miles on it...I bought it new in 2019, and I've typically driven it only a few times a year.

When I charge it to 90%, it shows a range of 200 miles now. I think it used to show 220-225 miles or so.

Is there a way to check when this performance degraded exactly? Is this within the range at which Tesla will actually investigate this as a service issue or am I out of luck?

What SOC had it mostly been at ?
What kind of climate? Parked outside or garage?

In average temperatures we would expect around 10% (10-11%) calendar aging if the SOC was mostly 70-90%.

 

[mg985]

Use the energy graph, get these values on the same picture and post here, and we will do the math for you.
The setting down right must be normal range, and the state of charge not too low (causes rounding errors), > 50% is good.

Thank you. Here is my picture. Also attaching pictures of the same screen at the other settings, in case that helps...

 

[AlanSubie4Life]

Thank you. Here is my picture. Also attaching pictures of the same screen at the other settings, in case that helps...

View attachment 1050492

48.6kWh as expected. 7.4% capacity loss from initial ~52.5kWh. Excellent.
(214Wh/mi*193mi/0.85 = 48.6kWh)

200rmi/0.9 = 222.2 rated miles, which is 92.6% of 240. (Also 7.4% loss, as expected.)

These are really excellent results for this vehicle. Continue to keep it low and cold.

 

[mg985]

At less than 2,000 miles per year, perhaps the car spent a lot of time parked at a high state of charge (>55% for an NCA battery like a 2019 SR+ has)? I.e. if the customer habitually charged it every day to 80% and drove <10 miles per day so that the car normally does not get below about 75%, then the battery would have been in the higher degradation state-of-charge range nearly all of the time.

If in a hot weather area, that could also lead to greater capacity loss.

I've always charged it to 90%, typically at superchargers.

I've typically charged it only a few times a year + then left it at the housing complex for 3-4 months (where there's no . Usually, by the time I'm back, it's down to 50-60%, typically after 3 months. One time, I forgot to charge it to 90% and it was at 40-50%. By the time I came back, it was down to 1% or so...

Car is in a temperate area (70 degrees Fahrenheit most of the year)