Dimension Engineering Sabertooth Dual 25A 6V-24V Regenerative Motor Driver. It says it can handle 25 A, does that mean it can handle a 12Ah battery?
Hi gradof6b,
Welcome to the RobotShop forum. “12Ah” (12 amp - hours) is a measure of the battery’s capacity ‘C’. The battery’s chemistry (lead acid, NiMh, NiCd, LiPo etc.) are more the determining factor if the battery can be continuously discharged at a specific rate. For example, if we consider 12 to be ‘1C’, a NiMh battery may be able to continously discharge at 1C ~12A. The same capacity battery composed of Lithium Polymer “LiPo” may be able to discharge at twice its capacity “2C” ~24A. A more recent chemical composition, NanoPhosphate “A123” is able to discharge at up to 30C, or roughly 360A.
If you are operating two DC motors at 25A each continuously, the total draw on your battery pack will be 50A. A motor controller may operate at 85% efficiency, so this value in practice is even higher. A 12V, 12Ah NiMh battery pack is only able to discharge at ~12A and will be irreparably dammaged if you try to draw 50A. Note too that the wires connecting the motor controller to the battery pack will ned to be significantly thicker than normal in order to handle the high current. A 22 gauge (0.0254" diameter) wire can only handle a maximum of 7A (less to be safe). In order to trnasmit 50A, you would need a 10 gauge (0.1" thick) wire. This of course also requires high current connectors.
Hope this helps,