Dead battery question?

dead. How long must I run my jeep (YJ) to get a good charge back. Thanks With the price of gas being what it is it might be cheaper to buy a battery charger.

1. If the battery was completely 100% dead (discharged,) it should be replaced. One or more cells are likely sulphated or otherwise damaged.
2. The alternator is not normally capable of doing a full recharge. To use the alternator to fully charge a completely discharged battery would take between 10 and 20 hours of running typically.

If you must try to recover the battery, I'd recommend a quality charger that can de-sulphate cells in addition to charging. Most of the smart chargers can do this. This may recover the battery sufficiently that you will get some life from it (but its life will be seriously limited by this...)