I charged my battery on the go today- I used my converter in my car on a short road trip- it took 80 min to charge from 15% to 100%- will be good for my road trips.
Buy a jumper pack with a built in cigarette lighter port and a 150w inverter (Make sure this isn't the backup jumper pack for your car).
So when your car is stationary, you can charge and leave your car off.