Why do batteries fail?
Normally, sulfur crystals build up inside the battery when discharging, and break apart when charging. However, if the battery isn’t fully recharged regularly, those crystals have a chance to permanently bond to the lead plates, reducing current until the battery doesn’t hold enough power to start the engine. Electrolyte evaporation caused by high temperatures and stress from low temperatures can increase crystal formation. Because of the range of driving conditions a car can experience, battery life can vary widely from less than a year to five or six years.
What do I need to consider when buying a battery?
Cold Cranking Amps (CCA) – This is the number of amps available at 32 degrees F (0 degrees C.) The higher this number is, the better the battery will perform in cold weather.
Amp Hours – This is the total amount of power available inside the battery when fully charged. The more amp hours available, the longer the battery can run the car when the engine is off.
Manufacturing date – The battery should be less than six months old to ensure maximum life.
Maintenance – Standard batteries will gradually off-gas electrolyte, requiring the cells to be topped up every few months. “Maintenance free” gel batteries hold the electrolyte in a silica gel so it can’t boil off. Absorbed Glass Mat (AGM) batteries are also maintenance free and are very vibration resistant, making them a good choice for off-roading.