battery and charger circuit

Hi, I'm in need of some help regarding a good way to integrate a proper rechargable battery and of course charger for the arduino.

Has anyone implemented this nicely? I'm running some LEDs, a 20x4 LCD, and a couple servos and would like to have that continue when the power brick is disconnected, and ultimately for at least 24hrs.

Thanks for any help!

I would 1st measure the total current the project is drawing. This will give an idea of the battery capacity needed. “Integrate” the charger and battery, are you going to use a standalone AtMega chip on its on PCB?

Buy a small 5-7a/h lead acid battery (12v), charge it with any old car charger, use it to power your projects for days on end (if your project permits)