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

[freeforall]

@freeforall
Your comment
“You might want to change that. Just charge at 50% only and plug it everyday instead of charging it at 80% once every 2 weeks. You almost don’t drive your car so technically, it is almost stored all the time. Also small depth of charges preserve much more the battery” …
is opposite to the advice I received from a Porsche HV tech, which was in effect charge only when needed rather than plug in every day. Reducing the number of charging cycles seemed to be good advice. But your SofH is unarguable!
As is your point that the range is currently sufficient for the OP’s need.

Unfortunately, the guy who said that to you has no clue. This is what science says:

As the experiment shows, it is more about depth of charge and not about #of charge cycles.
The 4 scenarios in the graph allow you to travel the equivalent of 1.5M kms for an EV that has 400km range. It shows you that a battery with 16880 cycles of charge but limited to 25% depth of charge for each cycle will have very low degradation vs higher depth of charge and much lower number of charge cycles (which is the option the tech was recommending to you)

Review this video from Dr Jeff Dahn and you will learn a lot about battery degradation.

 

[D00notD00d]

@freeforall Taycan uses a lithium ion LG E66a cell.
The example above is graphite.
Do you know if the conclusions are the same?

 

[SergeyIndy]

@freeforall Taycan uses a lithium ion LG E66a cell.
The example above is graphite.
Do you know if the conclusions are the same?

Per: https://insideevs.com/news/716351/porsche-taycan-efficiency-range/
Gen 1 uses NMC712 chemistry and Gen 2 NMC811, which to me is the same chemistry as NMC622.
Therefore, the conclusions @freeforall posted in those videos hold, but I am no expert.
At first, I treated the charging as I would a phone or laptop, but after learning about the conclusions above a while ago, I switched to low depth and frequent charging using the standard home L2 11kw EVSE and keeping the SoC in the 35%-65% range during daily use. However, I have not seen my SoH level off as of yet, as I am on a losing trend over the last 10k miles.

 

[D00notD00d]

Thanks @freeforall @SergeyIndy for this info.

I found this NMC specific video, which covers best and worst practices and their theory, is 12min long and references the 1hr Dr Jeff presentation linked at #796 above:


It includes the main recommendations from Dr Jeff to minimise degradation, which are:

1. If you can, use a SofC range such as 40-60%, or 50-75%
2. If you can, only charge up to 75%. Don’t charge to 100% unless necessary
3. When storing in a hot environment, store at a low SofC, e.g. 30%. Higher temperatures degrade the Battery more quickly.

Research constantly charging 3200 cycles of 40-60% (i.e. intended to represent charging everyday for 8.7 years ) indicated a SofH outcome of 85%.

Apparently Dr Jeff did 5 years research for Tesla. Not liking to rely on one expert, Google found this useful chart from

https://batteryuniversity.com/article/bu-808-how-to-prolong-lithium-based-batteries

The similar conclusion here was that 75-65% is optimum and 85-25% is better than 100-50%. If you can, stay between 75-25%, with the highest low point possible

The battery warranty responsibilities which Porsche levy on the owner can be found by searching the Drivers Manual in the App for High-voltage battery care. The manual has some important edge stuff about temperatures and storing the vehicle unused for more than 2 weeks, but the main points are:

• a maximum battery charge level of 80 % for daily use of the vehicle without any long-distance driving.
• If required, a battery charge level of 100 % can be programmed before starting long-distance driving.
• When the charge level is below 5 %, connect the vehicle to the mains supply after operation and charge the high-voltage battery.

 

[Svenson]

Yes, it's eFlow App, but Carscanner can get more data from EV.

Hi Chiu, the eFlow app focuses on ease of use, as well as interpreting and comparing the data it reads. Please feel free to share your feedback here in the forum or contact us directly if you are missing that you believe should be available for your Taycan.

 

[Svenson]

Same alert with Carscanner
After testing, the adaptation of eFlow app to CarPlay is quite basic and not very successful.

Hi Daniel, Apple only allows a list-style representation of data in CarPlay, but we hope they’ll loosen this restriction in a future update.

 

[Daniel]

Hi Daniel, Apple only allows a list-style representation of data in CarPlay, but we hope they’ll loosen this restriction in a future update.

Thank you for this explanation.
another question :Can we expect an update for the Macan EV?

 

[Svenson]

Thank you for this explanation.
another question :Can we expect an update for the Macan EV?

Yes, we’ll extend the compatibility to match the latest models, including the latest Macan.

 

[tchavei]

This thread has been invaluable to record our battery health and contributing to slowly plot an "average over time" for the Taycan battery technology.

However, as time passes by and more and more data points are added, slowly but surely, one stops being able to see the trees because of the forest i.e. it becomes very difficult to see the progress of each individual car.

I decided to plot my own graph with just my data (I searched for all data points I've been posting on this thread) and came up with this:

If someone has interest in doing the same, I can share the python code and instructions. It's quite easy as it only needs a csv file in format of:

km,health
1234,99.96
3456,98.56

and that's it. The graph will be generated automatically.

I'm actually considering making this available online where people can paste their data in the correct format and it will generate the graph for them (obviously free)

Cheers
Tony

 

[Bognar67]

This thread has been invaluable to record our battery health and contributing to slowly plot an "average over time" for the Taycan battery technology.

However, as time passes by and more and more data points are added, slowly but surely, one stops being able to see the trees because of the forest i.e. it becomes very difficult to see the progress of each individual car.

I decided to plot my own graph with just my data (I searched for all data points I've been posting on this thread) and came up with this:

If someone has interest in doing the same, I can share the python code and instructions. It's quite easy as it only needs a csv file in format of:

km,health
1234,99.96
3456,98.56

and that's it. The graph will be generated automatically.

I'm actually considering making this available online where people can paste their data in the correct format and it will generate the graph for them (obviously free)

Cheers
Tony

Those threshold lines are not so optimistic.... Many cars are over the 3Y mark around SoH 90%. Degradation is slowing down significantly as time is passing by (hopefully).
My car is 27 months old 43k km and 91% SoH recently. Will see how about at 36 months, hope around 90%.

 

[Vim Schrotnock]

This thread has been invaluable to record our battery health and contributing to slowly plot an "average over time" for the Taycan battery technology.

However, as time passes by and more and more data points are added, slowly but surely, one stops being able to see the trees because of the forest i.e. it becomes very difficult to see the progress of each individual car.

I decided to plot my own graph with just my data (I searched for all data points I've been posting on this thread) and came up with this:

If someone has interest in doing the same, I can share the python code and instructions. It's quite easy as it only needs a csv file in format of:

km,health
1234,99.96
3456,98.56

and that's it. The graph will be generated automatically.

I'm actually considering making this available online where people can paste their data in the correct format and it will generate the graph for them (obviously free)

Cheers
Tony

I do have concerns that our SOH readings are not completely accurate. You show no degradation whatsoever from 16,000 to 32,000. It's difficult to believe that a characteristic battery will show 10% degradation (assuming 100% at start) in the first 16,000 miles, and no degradation in the following 16,000 miles.

 

[g00se]

Newer Taycan (2024 GTS) and since delivery steady at 99.822 SOH. Just about 1800 miles in 2 months (no real daily commute) and DCFC maybe once a 2-3 times per month. Do not exceed ~80% on DCFC and keep battery in the 40-60% range for daily needs.

 

[tchavei]

I do have concerns that our SOH readings are not completely accurate. You show no degradation whatsoever from 16,000 to 32,000. It's difficult to believe that a characteristic battery will show 10% degradation (assuming 100% at start) in the first 16,000 miles, and no degradation in the following 16,000 miles.

I'm sure it's within the usual 1-2% as reported by multiple people that have got their real SoH from Porsche after the lengthy calibration procedure. We also know that the curve tends to flatten over time. Remember it has to stay above 70% for 160.000km and above 80% for the first 60.000km.

 

[Vim Schrotnock]

There is definitely something strange about the OBD SOH in the first few months. I've 'rebalanced' twice, and my indicated SOH has gone from 99.85 on June 6 to 96.01 on August 31 - a drop of almost 4% in less than 3 months. My range has not changed at all. I would be curious to know if this is something that is characteristic of our batteries, or we're just looking at inaccurate SOH readings.

 

[Tooney]

There is definitely something strange about the OBD SOH in the first few months. I've 'rebalanced' twice, and my indicated SOH has gone from 99.85 on June 6 to 96.01 on August 31 - a drop of almost 4% in less than 3 months. My range has not changed at all. I would be curious to know if this is something that is characteristic of our batteries, or we're just looking at inaccurate SOH readings.

SoH 96 - 99% on 2020 Taycan 4 years later! Outstanding!

(Yes, battery replaced... I know. )