Have you tried cleaning the charging port, it could be dust messing with it. Moving the ac adapter so it's angled while plugged in might help. It's bent ever so slightly by default, so bending it so it could be straight most likely did more harm than good. It doesn't seem like a battery problem, it seems like a charging port problem. If you really think it's due to the battery, then try getting a hold of a new one. No, you need tha battery in the console for it to function, and even if it were possible, I doubt this would help you, given that it seems like your charging port isn't functioning. If it's the og 3ds, then a dock might help, given that the contacts that the dock touches to charge the thing aren't dirty.