How long do the batteries last in storage?

[T Bone]

It snowed here finally and I haven't driven my car in a week. How long will the batter hold its charge?

I bought a BMW trickle charger but don't want to use it unless I have to.

Opinions?

[Aasteriniaan]

I would think that you wouldn't need one... I have no clue though... I asked my mother, in all BMW we owned ever... including 80s models... no battery changes ever needed.

[Ronan]

I store my performance cars in the winter..(heated garage).. I usually start them about once a month, run A/c at full blast for a while, and thats about it. The M6 is my second 6 series and it seems to be fine on batteries.

Interestingly my SL500 does tend to run down and shows a low battery warning after about a month.

[Wayward]

A good, modern (computer-controlled) charger is a worthwile addition to the garage. One caveat with regard to the M6 though, and it's with regard to lighter-socket based chargers -- and that's that the ligher sockets are disabled when the ignition is off.

You can obtain a lighter-socket adaptor from BMW for the glove compartment flashlight (to provide a lighter socket in place of the flashlight), however, that socket is on a timer -- and for all of one hour after the ignition is shut down, then it too shuts down.

The reality is that you'll need to acquire a charger with alligator clips, open the hood, and use the provided positive terminal and the negative ground bolt to charge the battery.

This isn't the greatest solution (pretty poor IMO) for those with rodents living in the vicinity (damn wire-chewers that they are).

In any event, you should try to keep the battery reasonably charged since when it drains, sulfates form on the plates and seriously and negatively impact it's longevity.

[T Bone]

Originally Posted by Wayward

A good, modern (computer-controlled) charger is a worthwile addition to the garage. One caveat with regard to the M6 though, and it's with regard to lighter-socket based chargers -- and that's that the ligher sockets are disabled when the ignition is off.

You can obtain a lighter-socket adaptor from BMW for the glove compartment flashlight (to provide a lighter socket in place of the flashlight), however, that socket is on a timer -- and for all of one hour after the ignition is shut down, then it too shuts down.

The reality is that you'll need to acquire a charger with alligator clips, open the hood, and use the provided positive terminal and the negative ground bolt to charge the battery.

This isn't the greatest solution (pretty poor IMO) for those with rodents living in the vicinity (damn wire-chewers that they are).

In any event, you should try to keep the battery reasonably charged since when it drains, sulfates form on the plates and seriously and negatively impact it's longevity.

Hey Wayward thanks...didn't know that.....

With any luck I will be FORCED to drive my M6 to the dealer tomorrow to install my Supersprint X Pipes and Race muffs.

[mkerouac]

I wouldn't let the car sit idle for more than a month without a trickle charger. I left mine for 3 weeks and it barely turned over.

[Aasteriniaan]

My bad... I misread the question... No car has ever been in storage either -.-