Mac mini battery life

I've not done any real power management yet, but so far I am getting about 1 hour of run time for the Mac mini from a fully charged 12V 7AH battery running through the CNX-P1900 DC-DC converter.

I have put 2 of those batteries in parallel now, so hopefully I'll get about double the run time.

I run all the motors and other electronics (dome logics and PSI LEDs, holoprojector LCD, speakers) off of a separate pair of batteries. He has 4 total batteries inside: 2 in the battery boxes and 2 in the lower body.

I plan on using the Phidgets' voltage level sensor as a monitored analog input for power management once I get into the programming end of things.