charging the 12 volt lithium battery

mojome

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I have been reading about the 12 volt battery system flaw in Taycan , and have seen on this forum about cars went dead suddenly. Some would keep lithium battery jumpers in the car and others would pop the frunk overnight so they would not be stuck. I just wonder has anyone tried to charge the 12 volt lithium battery periodically for the prevention measure.
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chrisk

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The problem is not with the battery itself. It is probably a software issue that drains the battery while the car is parked even if the battery is in good condition.

The Li battery is charged every time the car is on, I don't think any additional periodic charging will make a difference.
 

evanevery

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Popular speculation is that it is specifically the processes which "wake up" the PCM to change charging parameters automatically/remotely which are ultimately involved in draining the 12V battery.

The Timers and/or Porsche Connect "wake up" the PCM to alter the current charging profile and then the PCM does not go back to sleep (like it should). It stays running and then ultimately drains the battery. Its likely the PCM firmware which is at fault, but the issue only appears to be triggered when charging parameters are changed AFTER the car is shut down/parked.

In itself, being parked, or simply connected to a charger, has demonstrated very little drain of the propulsion or 12v batteries.
 

daveo4EV

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the drain is also high enough that there is reasonable speculation that a 12V trickle charger will not be able to "keep up" with the drain - ultimately leading to a dead 12V battery…once the battery is dead/too-low a relay is tripped and the 12V battery is no longer connected to any bus by which it could be charged - "jump starting" a taycan is _NOT_ charging the 12V battery - it's providing a 12V power source directly to the main computer power bus and when the computer is powered on it resets all the systems and trips relay's to bring various electrical component (including the 12V battery) back on line…

it's very unlikely in my opinion a 12V trickle charger would make any difference, and it is nearly a fact that once the 12V is dead the only method to get the 12V back online is to provide ample power via the jumper posts n the frunk.
 

Dee

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it's very unlikely in my opinion a 12V trickle charger would make any difference, and it is nearly a fact that once the 12V is dead the only method to get the 12V back online is to provide ample power via the jumper posts n the frunk.
I think it does.
1. The 12V battery isn't relatively big, 40Ah (that's also the reason it's easily drained).
2. A trickle charger has enough power to feed the electronics which power up the car, at least it adds extra power and that's always good.
3. Adding extra, constant charge during the moments the car isn't on is always better and DOES make a difference in the end (extra h in Ah is what cars do like).
Still, it's a fix for a different problem.

That is my opinion although I don't use a trickle charger cuz I've never experienced this issue on my car.
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