Battery cells reset/rebalancing after erratic SoC readings

[sor]

Also there is a lot of garbage data or perhaps incorrect formatting in car scanner from what I can see. It makes me not really trust the data that looks reasonable when so much of the data looks bad.

the highest voltage being 0. anything seems completely wrong, for example. My house Li battery backup cells are usually in the 3-4v range even when completely discharged.

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[Jetced]

@Fly4ever was your case also paired with slow charge speeds a HPC chargers? Currently I only get about 120kW at 400kW stations. And my range is incredibly bad. Last night I git home at 5% and 13km left. 2h later it showed 10% and 27km.
Wasn’t able to charge full as I had to leave in the morning. Will try to get very low again next week

 

[Fly4ever]

@Fly4ever was your case also paired with slow charge speeds a HPC chargers? Currently I only get about 120kW at 400kW stations. And my range is incredibly bad. Last night I git home at 5% and 13km left. 2h later it showed 10% and 27km.
Wasn’t able to charge full as I had to leave in the morning. Will try to get very low again next week

@Jetced,no my charging speed at ultra fast chargers was (and still is) fine,my only problem was the SoC % erratic behaviour.Now,almost 700Km later and many charging sessions at both slow,fast and ultra fast chargers everything is still o.k. and SoC shows me exactly what it should according to what the kWh/100Km indicator shows and what the charger reports I received as well after a charging session is completed.I calculated the SoC to be approx 90-95% accurate both during driving and charging as well.
Concerning range I'm getting around 420-430Km of highway driving with the car heavily loaded and OAT @15° C and driving speed around 115-130Km/hour - 97Km/hour average (20' snow tyres and forged light wheels).

 

[Philip_1]

After one year and due to change of user in Porsche center I had to calibrate the battery.It worked well.

Before and After Calibration

 

[Jetced]

After one year and due to change of user in Porsche center I had to calibrate the battery.It worked well.

Before and After Calibration

How many cycles did you do?

 

[Philip_1]

How many cycles did you do?

Difficult to read everything here, I will make as simple as I can to explain my procedure.

1: dropped to 1%, after about 8 hours BOOM 23%!
2: dropped to 4% after about 8 hours 14%
3: dropped to 4% after about 8 hours 6%
4: Charged to 100% without unplug it the car during charging changed 3 times the time of completion, and it adding more hours to reach the target of 100%. For example reached 90% and after a while became 73% again, finally 100% unplugged.
5: After few minutes dropped again to 85% and the range became normal.
6: I added estimated due to loses: 3.6KWh x 22hours = 75.6 kWh + 8kwh was already on start= 83.6kwh + 15% missing from totally battery level of my car now, I am very near to the Total battery capacity.
Equivalent to ~540 km at 100% (Display range!)

I hope I helped.

(All numbers are based on rough estimations due to loses etc).

 

[de0xyrib0se]

Note that the Battery Management System will rebalance the cells at both low (<20%) and high charge rates (100%). I'm surprised there isn't an official statement or at least a paragraph in the manual about this. You just have to be very careful with ambient temps when going the low route.

Mercedes for example recommends leaving the car at <20% every 6 months with ambient temps >= 10C, so that the BMS can rebalance the cells.

 

[Philip_1]

I never had problem so far until Porsche Center changed user to "guest"
They say that BMS will make the calibration as you mentioned, but I am not sure how effective is doing it with this software..I charged to 100% and the results was as per my photo above before calibration.
Later I found this procedure from Taycan forums and it worked at once..Range came back and actual amount of KWh near to the useable capacity as per specification enter the battery..
Before this...For first time, I was 95% and the navigation was saying arrival range 50% for 1.5km distance!!

Not planning to do this all the time..but now i am back on track as I was for a year now, but generally... PORSCHE NEEDS TO WORK SERIOUSLY IN THIS SOFTWARE AND MOREOVER TO TRAIN UNWILLING DEALERS TO DEAL WITH ISSUES AS THEY ARE OBLIGATED.

 

[de0xyrib0se]

The irony is the people that represent the brand in front of customers, the dealers, are not Porsche. Most of the time trying to get you in the shop for service hours.

Finding a good dealer is more important than finding a car unfortunately.

Neither are the people writing the software, VW...

 

[Philip_1]

The irony is the people that represent the brand in front of customers, the dealers, are not Porsche. Most of the time trying to get you in the shop for service hours.

Finding a good dealer is more important than finding a car unfortunately.

Neither are the people writing the software, VW...

It is true by 100%...... You go there and they JUST looking your car.... and then they say it's okay! You take it back and then you will find that they did nothing..
Don't get me wrong the car is impressive by all means..But dealers and service stations proven to be incompetent.... Strange but a fact..
I own also one T-Roc - VW and for 5 years ZERO issues... I understand different technology but cost is also five times less..

 

[de0xyrib0se]

If you find a good dealer that cares, cherish it...

BMW dealer tried to convince me I damaged my own car after they put two dents into it during an oil change! Same crap all over the place.

 

[Philip_1]

If you find a good dealer that cares, cherish it...

BMW dealer tried to convince me I damaged my own car after they put two dents into it during an oil change! Same crap all over the place.

Wow.. that's bad..So far the most positive experience I had is with Mercedes..ln Greece, not sure for other countries..

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