- First Name
- Andreas
- Joined
- Oct 1, 2024
- Threads
- 13
- Messages
- 108
- Reaction score
- 44
- Location
- NJ
- Vehicles
- Macan Turbo EV, E-tron, M3
- Thread starter
- #1
Here are my $0.02 on the 12V EV issue my car was (is) plagued with.
A few weeks ago, my car had to be towed to the Dealer as the 12V battery was dead. (consequently, also damaged).
At that time no one knew what caused it. I was told i had a bad cell in the 12V battery.
Well now i have a new battery and it seems it is going slowly in the same direction.
To be fair i have to say now i have a dashcam installed so now i know for sure i have a draw during Parking. But i also have an additional 12V battery B130X for my Blackvue system to take the strain off the Porsch battery a little.
Either way here is what i came up with in regard to how my Porsche handles its little 12V "sister" battery.
It only charges the 12 Volt battery during...
1. Driving or when the engine is on (highest Charging power) 14-15V
2. DC or AC Charging of the big battery charges the 12V also but not as intense as driving. ~ 13V
3. And i also think when you precondition the car it will give its 12V sister a charge.
I wish the Porsche app would give out a battery reading of the 12V SoC. luckily my Blackvue Dashcam (app) does that so i can tell what the SoC of the 12V is at anytime from anywhere.
So, my advice to anyone who wants to make sure their 12V side of the car is not dead when they come back home after a few days or weeks. (OfCourse a nice Trickle charge if your car is parked inside is a smart thing while being away for longer.) But not all have a Garage for the car.
Next best thing: You are parked outside your house and have a Level 1 or 2 charger nearby. Advice. Keep it plugged in and have the cars big battery at a lower SoC.
MY approach is to set my Charging power to a lower 20Amps or such that's roughly about 5kW (more or less). Then change remotely when you feel like you want to give your 12V a charge remotely drag you charge level gage in the App from let's say %30 to %50 the first time and if needed again %50-%80 it would take longer to reach that with 5kW and thus charge your 12V longer as the process takes longer. If you can't control your charge power, then try out what works best for you. Technically you can also charge it up full (or almost) fast and then preheat your car regularly and that also charges your car but will of course use (waste more 800V energy) but that's ok as you have it charged up . You could technically hover btw the save %80 and down to %50 and back up. A strange workaround but it is an option if needed.
Allll this because Porsche it seems has not build in a Voltage threshold where it would kick in a charge of the 12V system to maintain it or recharge it before it reaches a dangerous low SoC.
At least that is what i had come up with so far. I hope i am wrong and there is a silver lining but so far i have not seen it.
I am actually German and grew up in Stuttgart. But i must say despite the Beauty of this car and its speed and handling. I am disappointed that my fellow German engineers did not think this through. (as far as i can tell)
Disclaimer: I reached out to Porsche in Germany and the ones i get on the phone. No one knows. %50 of the time i get rerouted to Porsche North America. And they know even less. As the Germans don't see an importance sharing things with their partners oversees or elsewhere.
Everyone is left guessing around.
I set my Dashcam to a voltage cut-off @ 12.5V just to be safe. the Bluackvue default i think is 12.1 V. But with the car and no "build in" Safety net you have to keep it higher. Let's see where this all goes.
A few weeks ago, my car had to be towed to the Dealer as the 12V battery was dead. (consequently, also damaged).
At that time no one knew what caused it. I was told i had a bad cell in the 12V battery.
Well now i have a new battery and it seems it is going slowly in the same direction.
To be fair i have to say now i have a dashcam installed so now i know for sure i have a draw during Parking. But i also have an additional 12V battery B130X for my Blackvue system to take the strain off the Porsch battery a little.
Either way here is what i came up with in regard to how my Porsche handles its little 12V "sister" battery.
It only charges the 12 Volt battery during...
1. Driving or when the engine is on (highest Charging power) 14-15V
2. DC or AC Charging of the big battery charges the 12V also but not as intense as driving. ~ 13V
3. And i also think when you precondition the car it will give its 12V sister a charge.
I wish the Porsche app would give out a battery reading of the 12V SoC. luckily my Blackvue Dashcam (app) does that so i can tell what the SoC of the 12V is at anytime from anywhere.
So, my advice to anyone who wants to make sure their 12V side of the car is not dead when they come back home after a few days or weeks. (OfCourse a nice Trickle charge if your car is parked inside is a smart thing while being away for longer.) But not all have a Garage for the car.
Next best thing: You are parked outside your house and have a Level 1 or 2 charger nearby. Advice. Keep it plugged in and have the cars big battery at a lower SoC.
MY approach is to set my Charging power to a lower 20Amps or such that's roughly about 5kW (more or less). Then change remotely when you feel like you want to give your 12V a charge remotely drag you charge level gage in the App from let's say %30 to %50 the first time and if needed again %50-%80 it would take longer to reach that with 5kW and thus charge your 12V longer as the process takes longer. If you can't control your charge power, then try out what works best for you. Technically you can also charge it up full (or almost) fast and then preheat your car regularly and that also charges your car but will of course use (waste more 800V energy) but that's ok as you have it charged up . You could technically hover btw the save %80 and down to %50 and back up. A strange workaround but it is an option if needed.
Allll this because Porsche it seems has not build in a Voltage threshold where it would kick in a charge of the 12V system to maintain it or recharge it before it reaches a dangerous low SoC.
At least that is what i had come up with so far. I hope i am wrong and there is a silver lining but so far i have not seen it.
I am actually German and grew up in Stuttgart. But i must say despite the Beauty of this car and its speed and handling. I am disappointed that my fellow German engineers did not think this through. (as far as i can tell)
Disclaimer: I reached out to Porsche in Germany and the ones i get on the phone. No one knows. %50 of the time i get rerouted to Porsche North America. And they know even less. As the Germans don't see an importance sharing things with their partners oversees or elsewhere.
Everyone is left guessing around.
I set my Dashcam to a voltage cut-off @ 12.5V just to be safe. the Bluackvue default i think is 12.1 V. But with the car and no "build in" Safety net you have to keep it higher. Let's see where this all goes.
Sponsored
