Battery Voltage problem

[j801642]

We are having a problem where the voltage is dropping down to the scary range of 7-9V while just driving around. Sometimes we will not being manipulating the robot at all and the power will drop from 12V to 9V. We have a 4 CIM 8 inch Pneumatic wheel AM14U3 drive train. We have two CIMs working our lift. These are all hooked up to 40 amp breakers on the PDP. We have a window motor hooked up to a 20 amp breaker on the PDP. There's also a compressor, camera, wireless, and two servos all hooked up in their respective ports as well. This is the most power we've had on the robot in the four years I've been doing FIRST and I don't know if this is normal usage with this type of setup or is it a problem with connections? We've tested with multiple batteries all reporting 130% and a condition of "Good" on the battery beak. After using one of the battery for ~10 minutes the battery beak reported a charge of 96%. I'm worried we will go to play a full match and the robot will brownout. What troubleshooting steps should I be taking to try to fix my problem.

Thanks,
Isiah L.
Team 128 Electrical/Programming Team