Why Do Car Batteries Die?

Most car batteries have a maximum life span of five years. Recharging from the alternator is the only thing keeping it from dying out quickly. Other factors, however, can make the battery die sooner, especially in regard to the car's other electric devices that the battery powers.

Function

The alternator recharges the battery once it is used to start up the car. A faulty alternator will cause the car to drain the battery power.

Warning

Starting and stopping the engine within a short time span will cause the battery to eventually die. The alternator on average requires 20 minutes with the engine running to fully recharge the battery.

Effects

Leaving any lights on while the car is off will drain the power from the battery. Electronic devices within the car like the stereo or a DVD player will do the same.

Geography

A battery can fail from extreme temperatures as it causes a problem with the chemical reaction needed to generate the power. The insulated jacket most batteries are encased in can prevent this.

Prevention/Solution

Hooking up a second battery for the car's other devices will increase the life span of the starter battery.