i was messing around with some old batteries and my gba and i was running my gba off of rechargable ni-mah's from an old cell phone. i wanted to upgrade to li-ions that are the same voltage, but my gba won't turn on with the li-ions. i did not short it, the batteries are charged, and i know i'm getting no more than three volts, why won't it turn on?

can i use a gba sp rechargable battery? would it help to use those instead of cell phone batteries?
or should i just save some time and use rechargable AA's?