RE: Digital Servos and Battery Requirements
Larger battery capacity does not always equal larger peak current delivery. Some AA cells are rated at more than 2000mAh but cannot deliver the short peak current that high-torque digitals demand. One cell I like to use for smaller airplanes is the 2/3A 1200mAh, commonly used to power 1:18 scale RC cars. Some of them can sustain 25A of continuous output. I've used 5cell packs made of these 2/3A cells to power up to 50-60cc class airplanes.