How are LFP batteries holding up?

[kelvin 660]

LFP batteries have been around now for about 9 months and I was wondering how they are holding up in terms of degradation.

So do you have a SR+ with LFP batteries? Do you use TeslaFi? If so, can you post a PDF of the battery degradation chart?

As an example, I have posted a PDF of mine. However it uses NCA batteries. According to the chart it has lost 9% in 12 months. It will be interesting to compare this with LFP to see if there is a major difference...

 

[kelvin 660]

It's early days, but no signs degradation from my LFP batteries, compared to NCA batteries of my first SR+ that took a steep drop from ~240 down to 235 at the same mileage.



It seems that LFP batteries are starting to become the technology of choice for "base" vehicles due to robustness and safety...

 

[davidmc]

NCA here too. You have very similar predicted range

 

[Burley]

You might find Gogo Chang's latest video informative.. LFP Degradation after 12,000km

 

[MrBadger]

Worth noting that the TeslaFi reports and other similar extrapolations are what the BMS thinks may be the range but, being a non exact science, may be well out from the reality of the battery condition itself.

We recently had our BMS CAC (calculated amp hour capacity) reset as that value can drift widely off by many % and we got our full range back according to TeslaFi battery report and extrapolating %/mileage on display. We have been told to monitor in case of a more serious issue (I would like to think that Tesla tested things before the reset) but, tbh, whilst its nice to see the range back at more respectable levels, the only way to really know is to see how it performs over several long drives.

Without putting numbers on things, here is ours... where the CAC was reset is obvious.

 

[DrJFoster]

The issues with the LFP battery when they came out were largely linked to temperature. I think until the temperatures start to fall again we won't know how they perform in the cold or whether Tesla have sorted out the issues in software. .

 

[kelvin 660]

NCA here too. You have very similar predicted range

Yes, we do have a similar predicted range but your car has traveled 3 times further and is almost 3 times older!

 

[GRiLLA]

I wouldn't read too much into these graphs, it's basically extrapolating what the BMS thinks if the charge ends a that percentage. The BMS will happily reconsider as it actually gets to 100%, and particularly if you often charge to 80% without the car going to sleep (i.e. sentry) then it's had very few points to consider.

 

[JIBYC]

Worth noting that the TeslaFi reports and other similar extrapolations are what the BMS thinks may be the range but, being a non exact science, may be well out from the reality of the battery condition itself.

We recently had our BMS CAC (calculated amp hour capacity) reset as that value can drift widely off by many % and we got our full range back according to TeslaFi battery report and extrapolating %/mileage on display. We have been told to monitor in case of a more serious issue (I would like to think that Tesla tested things before the reset) but, tbh, whilst its nice to see the range back at more respectable levels, the only way to really know is to see how it performs over several long drives.

Without putting numbers on things, here is ours... where the CAC was reset is obvious.
View attachment 710057

What sort of % reduction did you need to qualify for a CAC reset?

 

[theothertom]

We recently had our BMS CAC (calculated amp hour capacity) reset

How did you go about getting it reset?

 

[MrBadger]

What sort of % reduction did you need to qualify for a CAC reset?

It was an add on item to an existing service request otherwise I would not have bothered. I just put that I thought that the 100% range should have been higher than it was (sorry to be coy about the real numbers because they are largely meaningless best guess numbers with a large % for error but I will say that if they were real I would be a bit pissed off) and left it to them. I was aware that BMS can drift wildly and was probably more calibration rather than anything physical, but I had two noticeable sudden drops in the past and wanted to them to check that they were not caused by a partial failure. I then left it up to them. It was listed on the invoice as remote diagnostics so probably nothing to do with the actual visit to the service centre. Its now a matter of monitoring over time - far too early to draw any conclusions but at least the concern is in their system.

 

[Darmie]

You might find Gogo Chang's latest video informative.. LFP Degradation after 12,000km

I think the same information can be located in Scan My Tesla. Not sure if there is a pass through in his car though for the OBD plug.

 

[theothertom]

It was an add on item to an existing service request otherwise I would not have bothered. I just put that I thought that the 100% range should have been higher than it was (sorry to be coy about the real numbers because they are largely meaningless best guess numbers with a large % for error but I will say that if they were real I would be a bit pissed off) and left it to them. I was aware that BMS can drift wildly and was probably more calibration rather than anything physical, but I had two noticeable sudden drops in the past and wanted to them to check that they were not caused by a partial failure. I then left it up to them. It was listed on the invoice as remote diagnostics so probably nothing to do with the actual visit to the service centre. Its now a matter of monitoring over time - far too early to draw any conclusions but at least the concern is in their system.

Thanks!

 

[cdswm3]

LFP batteries charge much slower in cold temperatures.

 

[kelvin 660]

LFP batteries charge much slower in cold temperatures.

I don't think there is a problem using a home 7 kW charger? and if you are on a road trip the batteries get pre-conditioned, so again it should be a problem... unless you know differently?

 

[theothertom]

LFP batteries charge much slower in cold temperatures.

According to Bjorn, the initial Tesla LFP charge times were "not so good" (he used a more colorful term) but apparently Tesla fixed that by heating the battery. Start watching at time 11:24

 

[kelvin 660]

According to Bjorn, the initial Tesla LFP charge times were "not so good"

Well Bjorn's video shows the LFP was fastest to 100%. Anyway, I don't road trip every day so even if it is slower that might be an advantage because most time's the car is ready at a SuC before I've been to the loo and got some refreshments...

PS I pick my LFP car up tomorrow and will report back as we go into winter and get some cold weather...

PPS no one on this forum with LPF battery, got a TeslaFi battery report that they can share?

 

[thewanted]

PS I pick my LFP car up tomorrow and will report back as we go into winter and get some cold weather...

Enjoy your new car I'm very curious about how the LFP pack will hold up in winter. Unfortunately Bjorn's spreadsheet doesn't have any data in it yet, but I'm sure he'll re-test the car in winter.

 

[theothertom]

Well Bjorn's video shows the LFP was fastest to 100%.

It is fastest to 100% if the battery is warm. But the question was about charging when it's cold.
Initially LFP charged slower in cold weather but Bjorn said Tesla fixed that, probably with a software update to heat the battery.

The real question in my mind is cold weather range when you first start the car in the morning(cold battery). According to the data I've seen, LFP looses much more range than NCA is cold weather unless the battery is heated. I'm wondering if Tesla has fixed that as well. Let us know!

 

[GtiMart]

But the thing is, the range is not lost on NCA, it's unavailable, and it comes back as you drive. That is my understanding at least. I presume it's the same for LFP so your question is how much range is temporarily unavailable?