I use a car jumper/charger. Costs $125 +/-, but it's easy to carry around, has A/C and D/C and USB ports, tons of power, and it may come in handy with your F-150 some day. Just keep it charging when you're not using it, and it's always ready to go. I tried a couple of the little pocket chargers costing $60. Small and convenient, but I found they don't hold a charge for s***. Amazon's got them by the dozen.