External display and battery

[fallenapples]

I have recently connected my Macbook Pro to an external display while in sleep mode. After doing some research it said it must connected to AC power in order to use an external display in sleep mode.

Now that I have done that, the percentage goes down about 2% each day while plugged in and will not charge anymore. Can I overcharge my battery? Because when I check it says it is not charging.

 

[carnageX]

Generally no, you can't overcharge Li-Ion batteries because they have protection circuits built in and will switch over to trickle-charge when full (meaning it will go down a few percent, then start to charge up again, and repeat).

It's possible that the circuits in the battery (or from the board to the battery terminals) aren't in some "charging mode" and it's not switching over to charge the battery, but rather just let it keep draining.

When it's turned on and running correctly, does it charge then?