While batteries can survive five years or longer if they are adequately looked after, many car batteries are worn out and inefficient within 3 years of daily use under standard conditions. Just like the battery of your computer or smartphone decreases with every charge, the battery of your car gradually worsens whenever the engine is charged. It is generally time to install a car battery replacement after three years.   Most of the car batteries will be almost unreliable after four or five years. There are a variety of safety and reliability problems with old car batteries. Fortunately, it is easy to determine if the battery of your car is reaching the end of its life.