🔋 Baseline for HV Battery SoH Performance (Battery Degradation Data by Taycan Owners)

[Gru]

That said )), I did use close to an entire 2 year's worth of charging GoM ranging predictions (Post 1) wherein I can see an 'average' loss of range for year to year (which averages over seasonal GoM 'losses') which calculates to ca 10% decrease in overall per annum average range - this actually happens to near perfectly match my 12% loss in SoH but even that comparator needs to be judged carefully.

?
after almost 1yr of data (and thank you ? again for all the work !) I have the feeling that the decrease doesn’t depend much on how you drive, how you charge (slow/fast, up to 100% or not), but most likely on a parameter one can‘t control : the climate where you live... ie the « idle » temperature at which the battery is stored since these vehicles are parked 90% of the time.

Conclusion….. just enjoy and drive it ! ?

 

[ciaranob]

?
after almost 1yr of data (and thank you ? again for all the work !) I have the feeling that the decrease doesn’t depend much on how you drive, how you charge (slow/fast, up to 100% or not), but most likely on a parameter one can‘t control : the climate where you live... ie the « idle » temperature at which the battery is stored since these vehicles are parked 90% of the time.

Conclusion….. just enjoy and drive it ! ?

Thx and yes, that was the premise for the thread - the suggestion that climate is the dominant factor in Soh longevity which of course for those in the know is not exactly news I guess !

But I was pleased to see how well the data that we do have tracks the climate zones very well and of course there will always be outliers - any definition of a climate zone will have geography with micro-climates so cars will cross plot.

PS: Thx for the support!
PPS: 100% re just drive it!

 

[ciaranob]

In my experiences, predictions were most od the time very close to real consumptions.

Are you perhaps referring to predictions when using Nav on a per trip basis? If so I agree entirely - the PCM calculation based on an active trip in respect real time range remaining, arrival SoC and terrain impacts etc. are remarkably accurate.

However the orig comments were referring to just the GoM range max. you get after an AC or DC charge when compared against recorded cumulative range over multiple trips for that charge window - not many folk have actually done that - alternate is to track average consumptive data from the PCM against real world measured/calculated distances etc.

 

[B61]

I wanted to say that when I got 400km after charge to 100%, then (for instance) I made about 300km and 25% of SoC remains.
And, yes, I’m using navigation on almost all of my drives.

 

[Tooney]

Conclusion….. just enjoy and drive it ! ?

+1

 

[Tooney]

OK - so the dealership has read the Soh via PIWIS and drum roll .............. it is the EXACT SAME number as I got from my OBDII tool on drop off. This is the fourth independent test whereby a Forum mbr. has taken a reading and had their dealership (3) or a licensed 3rd party (1) deliver a SoH readout that was either the same or 1-2% different to that from the OBDII tools.

My car's readout on PIWIS - MOST importantly this is a "Quick Readout" as stated on the PIWIS screen - I have no idea if a full multi-hour/day deep test would produce a markedly different result:

Any info from forum members or dealer service people as to how SoH readings from PIWIS quick readouts compare to those from "deep test" SoH readings I assume Porsche uses to check battery warranty?

 

[ciaranob]

Any info from forum members or dealer service people as to how SoH readings from PIWIS quick readouts compare to those from "deep test" SoH readings I assume Porsche uses to check battery warranty?

Nope and indeed why I mentioned it Suspect harder to extract that kind of info unless you have a very amenable dealership as from what I can see they are a bit touchy about sharing the Soh readings! But also the deep test is expensive in respect labor time so prob very rarely done TBH.

 

[SergeyIndy]

Nope and indeed why I mentioned it Suspect harder to extract that kind of info unless you have a very amenable dealership as from what I can see they are a bit touchy about sharing the Soh readings! But also the deep test is expensive in respect labor time so prob very rarely done TBH.

I was surprised that my dealership totally refused to provide me SoH reading at delivery. Warranty doc states that it is expected to be delivered with 100%. My reading because of this thread was 99.95% as soon as I got the reader but now I am at 95% @1k miles which is a bit steep drop for such low miles, but I understand not unexpected.

 

[bsclywilly]

Here’s a study that confirms the climate affects on battery aging. Just as @ciaranob concluded months ago!

https://electrek.co/2023/09/18/tesla-battery-longevity-colder-climate-study/

And quoted study here:
https://www.recurrentauto.com/research/it-matters-where-your-used-ev-comes-from

 

[Tooney]

I apologize if this item has been covered previously.
How repeatable are OBD SoH values?
At a point in time - say within a couple days - are SoH readings for a Taycan relatively constant in spite of a change in:

• ambient temperature
• battery temperature
• battery SoC
• length of time since battery was last charged?

 

[Scandinavian]

OK - so the dealership has read the Soh via PIWIS and drum roll .............. it is the EXACT SAME number as I got from my OBDII tool on drop off. This is the fourth independent test whereby a Forum mbr. has taken a reading and had their dealership (3) or a licensed 3rd party (1) deliver a SoH readout that was either the same or 1-2% different to that from the OBDII tools.

So all the negative comments in a separate thread re the trustworthiness of the OBDII tool are so far entirely unjustified. Would like of course to have more folk do this and hopefully we'll get additional 'dual' readouts.

Good news in a way, but maybe not so surprising? I guess both tests, with PIWIS quick test and OBD reader just reports a value stored in a memory in a ECU?

So then It all depends on how accurate the value is that is stored in the ECU!

In my case with a problem in my HV battery now, the SoH was still showing the same value as before any trouble started, about 90%??? But my actual driven range and SOC fell off a cliff face. There was no difference at all in the consumption per 100 km. My battery has two modules that needs to be replaced under warranty, so how the measurement of SoH stayed so high is a mystery to me.

I think the only reliable way to get a result about the state of health of the battery, is to drive the car from 100% charge to a low level <10% (maybe even <5%) and see the kilometres driven and the consumption in kWh/100 km. (or the equivalent in miles etc). And then calculate how much energy the battery held when full and compare that to a new battery capacity. It will require a long drive of course, probably around 400 km+.

I also think that is why the dealers are reluctant to do a proper SoH measurement. It would tie up resources and equipment over a long period. They would need to charge the battery fully and then discharge it in a controlled way. And the discharge would have to be measured with reliable instruments and likely regulated to simulate a real driving cycle? With idling, acceleration, regeneration etc etc.

 

[Johann55]

They would need to charge the battery fully and then discharge it in a controlled way.

Or rather the other way around, just like in Tesla service mode: discharge the battery down to 0 (by running the heater while car is stationary), then AC-charge it in a controlled way to 100%.

Probably 2 working days at the dealership...

 

[ciaranob]

Good news in a way, but maybe not so surprising? I guess both tests, with PIWIS quick test and OBD reader just reports a value stored in a memory in a ECU?

So then It all depends on how accurate the value is that is stored in the ECU!

In my case with a problem in my HV battery now, the SoH was still showing the same value as before any trouble started, about 90%??? But my actual driven range and SOC fell off a cliff face. There was no difference at all in the consumption per 100 km. My battery has two modules that needs to be replaced under warranty, so how the measurement of SoH stayed so high is a mystery to me.

I think the only reliable way to get a result about the state of health of the battery, is to drive the car from 100% charge to a low level <10% (maybe even <5%) and see the kilometres driven and the consumption in kWh/100 km. (or the equivalent in miles etc). And then calculate how much energy the battery held when full and compare that to a new battery capacity. It will require a long drive of course, probably around 400 km+.

I also think that is why the dealers are reluctant to do a proper SoH measurement. It would tie up resources and equipment over a long period. They would need to charge the battery fully and then discharge it in a controlled way. And the discharge would have to be measured with reliable instruments and likely regulated to simulate a real driving cycle? With idling, acceleration, regeneration etc etc.

Agreed - said pretty much the same thing a few posts back I.e. re a proper consumptive test to back calculate SoH a good way to compare against the OBDII data and re the PIWIS ‘quick’ test indeed likely not too different if at all to our OBDII ‘flash’ read. Suspect a full test is only done when a warranty claim is submitted (outside of a component failure case like yours) due to time/cost involved

We did had at least one mbr have that 3rd party do a proper multi-step, multi-day full SoH evaluation and it’s was ca 1.5% different to his own OBDII prior (although think his read was about a week bef).

The issue w.r.t. the ‘failing state’ of your battery with no update to the health status apparently being synchronously logged is the most weird thing to me - I would assume the SoH was a continuously updated ‘state’ and essentially a real time ‘flash’ read in the cars system but perhaps not!

 

[Johann55]

When battery modules are failing the Battery Energy (kWh) seems more up to date than the SOH.

 

[Maxzor]

Great stuff - thx and will upload today - def track battery type - the RWD always has great range it seems largely due to weight savings (at least likely the biggest discriminator) but indeed your range tests impressive!

Do you recall if that dealership readout was from a PIWIS based test result- presumably so? Important as we have very few to compare against and actually would be great if you could grab an OBDII tool to measure via PCM to compare despite added mileage! I

I think it s a quick read out via the PIWIS.

I have an OBDII tool, use it for another car. Will try to see ini can get it to work on the Taycan.