Portable Power System Station is simply a larger version of cell phone portable chargers with the addition of positive and negative battery lines for connecting to the car battery. they can, however, do even more because most portable car battery charger banks contain USB plugs that can charge multiple cell phones at once. When the battery bank needs to be recharged, plug it into a wall socket or a 12-volt automobile outlet. Everything is charged on a single system: An excellent portable power station allows you to charge all your electronics and run small appliances simultaneously.