Choosing a Battery

[badtkee]

Hey Guys,

I'm new to the robot building world and I need help calculating what size battery I need for my robot.

Here are some of the specs of the robot:

1. Its a 2-wheeled robot, where each wheel is connected to a CIM motor

2. The robot needs to be driven continously for at least 45 min at a speed of 3m/s on one battery charge

3. The robot needs to carry a payload of 50lbs

4. Right now I'm planning on using 12.5" diameter wheels, but this can change

5. The robot will use an Arduino Uno microprocessor

I'll think thats the basics, if more information is needed I can let you guys know.

Thanks for the help!