I have used a CAT portable battery pack with good success,way more convenient than jumper cables between vehicles.I always kept it charged up ,but on this last hunting trip it was inadvertently run down flat ( kids powering their stuff)and now it won’t take a charge.Took it apart and put it on a trickle charger, but I guess it’s just too far gone.Next is to try and get a replacement battery rather then chuck the whole thing.I’ll let you know...