This Instructable will show how to power your Arduino Uno with four rechargeable AA batteries. You will need:
An Arduino Uno
4 AA battery holder (I HIGHLY recommend this one from RadioShack, as it not only has an internal switch for turning on the Arduino, it also has the necessary wires needed to plug into the Arduino Uno)
4 rechargeable AA batteries, at 1.25V each. (The reason why we should be using rechargeable batteries is because they are efficient and give the Arduino Uno the perfect amount of volts at 5V)
Stanley #1 Screwdriver or something similar
Step 1: Step 1: Insert the Batteries
Find the screw on one of the sides of the case, and remove it with the screwdriver, then slide the lid so that the battery holder is uncovered. Place your charged rechargeable batteries in the respective orientation. Finally, slide on and screw on the lid again.
Step 2: Step 2: Plug the Cables In
Plug the positive, red cable into VIN, and the negative, black cable into one of the GND ports. Then, turn the switch on the battery case to ON.
Step 3: Step 3: Run Your Arduino Uno
Your Arduino Uno should now run!
MikeM189 made it!