My flying field as no electricity available, so I would like to know the bestpower sourceto use for my charger to charge my LiPo.

I know that I can use my car battery but how much charge I can do before draining it without needing to start the car to recharge the battery, if my bigger Lipo pack is 10000mah 5S (18.5V)?

Or can I use some deep discharge marine type battery as a power source? Or something else?

Thanks