When a car battery completely discharges, it takes time and the application of a continuous low current to properly recharge it. Simply jumping a dead engine battery and taking a short drive will not be sufficient. To properly bring the battery back up to full charge, use a trickle charger. These are available at hardware and automotive supply stores.
Park your car near an electrical outlet and open the hood. Place the trickle charger on a flat solid surface either near or on top of the engine.
Connect the trickle charger's black clamp to the black terminal on your battery, and the trickle charger's red clamp to the battery's red terminal. Plug the trickle charger into an outlet. The charger will have a charging light that will light up if it is charging. Many models have a red error light if you have crossed the connections. If you see this red light activate, disconnect all connections and then reconnect them, making sure not to cross wires.
Let the trickle charger sit and charge for several hours, preferably overnight. Trickle chargers provide a low-level steady charge to the battery, and thus require a large amount of time to fully charge an automotive battery. A nice feature of a trickle charger is that you can leave it on indefinitely without worrying about overcharging. The trickle charger will typically have a green light when the battery is fully charged.
