2020 Model X plugged in and not in use for 2 months: 12V battery

[Bijli123]

Hi Friends,
I am traveling for the next 2 months and my Model X will be plugged in but not driven.

Will it causes discharge issues with the 12v battery? I know in many cases, the 12V battery is charged solely through the alternator in gas cars. Is that the same with the Model X or will it be charged as long as the main battery has juice.

Thanks and really appreciate your help.

 

[mxnym]

The 12V should be fine with your vehicle plugged in. The on-board systems regularly charge the 12V from the HV even while parked and not plugged in. The only exception to this behavior under normal circumstances would be when the HV gets too low while not plugged in. That having been said, it may still be possible for you to come home to a dead 12V, for instance, the on-board systems couldn't kick in to charge again if the 12V died during too long of a sleep cycle, but I think that would imply the 12V was already bad and it could probably happen overnight while you are home just as easily.

 

[Les236]

Correct. Mine is plugged in and not used for 3-4 months every summer. Last year I did notice a lot of charging towards the end and that was because the 3+ year old 12v battery was starting to die. I had it changed once I got home. I left June 15th this year and set it to charge to 70%, then lower it to 50%. When it gets close to 50-55 I charge it back up to 70%. I have only had to do this once in the past month.

 

[Bijli123]

The 12V should be fine with your vehicle plugged in. The on-board systems regularly charge the 12V from the HV even while parked and not plugged in. The only exception to this behavior under normal circumstances would be when the HV gets too low while not plugged in. That having been said, it may still be possible for you to come home to a dead 12V, for instance, the on-board systems couldn't kick in to charge again if the 12V died during too long of a sleep cycle, but I think that would imply the 12V was already bad and it could probably happen overnight while you are home just as easily.

Thanks, this is really useful. I will keep it charged and see how it goes.

 

[Bijli123]

Correct. Mine is plugged in and not used for 3-4 months every summer. Last year I did notice a lot of charging towards the end and that was because the 3+ year old 12v battery was starting to die. I had it changed once I got home. I left June 15th this year and set it to charge to 70%, then lower it to 50%. When it gets close to 50-55 I charge it back up to 70%. I have only had to do this once in the past month.

Thanks for this info. Really useful. When you said that you noticed a lot of charging towards the end: was it on the car or the 12v battery and how did you find out.

 

[Silicon Desert]

Thanks, this is really useful. I will keep it charged and see how it goes.

Then just set it to charge at around 70%, not 100%

 

[mbp11]

Then just set it to charge at around 70%, not 100%

Excellent advice! changing to 100 will damage the battery (or reduce its lifespan)