Not sure if this would help, but I would set:
BATT_SERIAL_NUM,1
Otherwise I cant see anything wrong with parameters.
Also try BRD_BOOT_DELAY,3000 which doesnt hurt to leave in place anyway.
You definitely have a 0v (ground) and 2 CAN wires right?
Be sure to set these too, they are definitely required for both safety and performance:
BATT_ARM_VOLT,66.50
BATT_CRT_VOLT,63.00
BATT_LOW_VOLT,64.80
BATT_FS_CRT_ACT,1
BATT_FS_LOW_ACT,2
MOT_BAT_VOLT_MAX,75.60
MOT_BAT_VOLT_MIN,59.40
Since this is a big copter be sure to work through all the initial parameters, tests and tuning process thoroughly. The Methodic Configurator will step you through this.