So, what is the AC voltage that goes into the camera? Is it 7.2v or is that the battery voltage? For my Sanyo HD1000, the battery voltage is in the realm of 3.2v or something but the external voltage to charge is 5v. For my camera I run an external battery sled with AA rechargeables. I pull the regular battery, run off the external a while (never ran a full test on run time) and then insert the regular battery after a while turning off the external pack. That was the only way I could run the camera without it charging the internal battery or turning off when I plugged in the external pack. Good luck finding a solution to work with recording 12hours straight.