BMW 1 Series 123d: how often charge the battery?

Question

I sold my 123d to someone who wanted to export the car to to other country. Originally he wanted to pick up the car before Easter but due to the corona situation he asked me if I could leave the car in my garage by the end of June at the latest (which is also not a problem). When I briefly unlocked the car today there was an error message about the battery. I have now connected a charger (Deutronic EBL70-12) but unfortunately I cannot leave the part on permanently. Now my questions:

1.) How often do I have to charge the battery so that it doesn't discharge too deeply?

2.) Should I leave a window a gap open because of possible gases from the battery?

Thanks for help

Answer 1

So if it's an AGM battery, easily three months. This is the case with my Z4 and the AGM is from 2009. My Z4 and my 1 Series Convertible have the charging poles in the engine compartment. The battery that is in the trunk does not gas out anyway, and even if so, why open the windows?

Comments

Thanks for the information! I also connected the charger in the engine compartment. The car has been standing for about 1.5 months and the car is already warning about the battery. Ev. Was the battery not fully charged before or it is due to the alarm system which may draw more current than if there is none. I will connect the charger once a month. My Z4 feels the battery discharges less quickly (but is also older and has less electronics).

Regarding the gas - an AGM battery doesn't? Or is there an air vent near the battery? I think the gas will not be really healthy - that's why the window is a little open.

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I also drive an AGM battery with these BMWs for the first time, but current batteries have an exhaust hose when they gas. I just sold a Toyota that didn't have an AGM, a lead acid battery, I changed it and it had an appropriate hose that went outside.

But again, what good is the open window when the AGM is in the trunk. You worry where you don't need to.

Up until four weeks ago, both of my BMWs were constant for about 6 months without a break on the charger, on the AGM-compatible charger, and nothing happened, neither exploded or gasified the passenger compartment.

That should calm you down.

Answer 2

If a battery is installed in the passenger compartment, it also has a small hose to lead the detonating gases to the outside. This is connected to the top of the narrow side of the battery and connected to a connector on the plastic trough on the 1 Series. You can see if it is still there or if it was "saved" when changing the battery. Should be gray ...

Does your charger have a charge maintenance procedure? I know it from my charger in such a way that it switches to maintenance mode after being fully charged. If the voltage drops, the battery is automatically recharged. Say you only need to connect your charger once and well ...