Sounds like a bad battery......But the battery could be bad because the alternator is not charging. The alternator will not charge if it is not excited by battery voltage. With a completely dead (Bad cell) battery, the alternator will not keep the car running. If it was running OK in the recent past, it is most likely a catastrophic battery failure. I think you would have noticed, if the alternator was not working long enough for the battery to go dead.