It depends on the battery's condition, but in general, you'll have about 10-15 minutes of power left in a car battery after it dies. you can avoid wasting your car batteries by locating them in a position where they are safe from physical contact and corrosion. if the battery is likely to be exposed to water or extreme changes in temperature, it needs to be stored inside the house. if you store your car outside then choose an out of sight location that can't easily get wet or covered with snow when it snows. the engine bay–inside the living area–or at least close enough to an entrance so that help can arrive if needed are great locations for storing your batteries because these places stay warmer and dryer
how long can a car sit before the battery dies?
a car sitting still may discharge the battery by up to 10% per day. in that case, 3-4 weeks would be a good estimate of how long the car could sit before the battery dies.
the best way to avoid this would be to use a 12v battery tender charger connected to a receptacle inside the car and frequently turn on or start up the vehicle so that it can recharge its own battery. otherwise, if left without being used for an extended period of time, you will most likely have your cars alternator recharging from external power sources such as wall sockets or generators at home every few days.
how long does it take for car battery to die with lights on?
battery life varies dramatically depending on the driving habits, driving conditions, and even how often you start your engine.
it typically takes days to weeks of sustained use before a car battery will die completely. but jumpstarting your car can take care of being stuck temporarily for 10 minutes, provided everything else is working properly. this includes the starter relay and ignition switch relay. when you have both engines turning over but not starting up or firing right away, this means either the battery is dead or there's an electrical problem (usually related to the ignition). either way, it's best to contact a mechanic as this might be terminal and more involved than simply “jumpstarting it”