Charging On The Go...

I hate to burn gas, but if I wanted to drive more than 40 miles, would it be acceptable to install a generator to power my Manzanita charger which would charge the batteries as I use them, or should I convert the generators ouput to DC 144V and send it to the pack? Or should I just use the gas burning thing sitting in my driveway?

I notice the voltage reads below 144V as I accelerate, and wonder if that would blow the Manzanita if it were charging while the pack was in use.