AA Battery replacement

Hi, So I have a AA battery pack inverter for some EL wire, and I was wondering if it was possible to replace the AA battery's with a lithium Ion battery to reduce its size. What kind of voltage should I look for/do I need to take into account amperage?

It would be nice if you included voltages or at least the number of AA batteries.

If you are already using rechargeable AA batteries then voltage is not the issue Amp hours is.

If you are using ordinary batteries the voltage may not matter depending on the number of batteries. Electronics work in voltage ranges like Arduino boards work from 12 to 9 volts.

Ordinary 1.5 volt AA batteries may have only 600 mAh or less. (Mill Amp Hours)

Amp hours count rechargeable AA lithium batteries can have as many as 1300 mAh as a phone battery with 2 lithium cells at 2.4 volts may only have 750 mAh.

If your Inverter needs the 1300 mAh you wont have the amps with a 750 mAh battery.

Sure. Each AA battery offers 1.5V. Multiply that by the number of batteries it takes and that's the voltage you need. Chances are you won't find a lithium battery with the exact voltage. You may need to get one a bit larger and use a voltage regulator to bring it down to the right voltage.