How Long Do Car Batteries Live For?

How Long Do Car Batteries Live For?

Car batteries don’t usually demand very much attention. But when they get old, they often misbehave and can crank your vehicle’s engine so slowly that it won’t start.  It varies on how often a driver should get his or her battery replaced, but a somewhat basic rule of thumb is that a car battery lasts about four, maybe five, years, under typical driving conditions.

According to the Service Manager at, “normal conditions” refers to many factors that exist in theory but rarely seem to happen in reality. Normal in this case means the battery experiences full charge cycles, it is attached to a functioning charging system, and it isn’t providing power for a number of accessories. As you may imagine, normal just isn’t that common. In the real world, temperature extremes, vehicle vibration, short rides down the road and an ever-increasing array of electronic devices shorten a battery’s lifespan.

If you look at your lead-acid, maintenance-free car battery, it is easy to make sense of why these factors affect a normal battery. Inside the car’s plastic battery box are plates made of heavy materials, such as lead and lead compounds. These plates are suspended in a mix of sulphuric acid and water. A host of factors can disturb the arrangement and weaken the battery structure, which include:

– Extreme heat during the summer, which can speed up the chemical reaction inside a battery and  shorten its life.

– Vibrations from rough travel may shake loose or damage the plates.

-Driving distances can affect the reaction, too. If you take lots of short trips or have a short commute, the battery never gets fully charged and this constant state of undercharge results in “acid stratification” which hinders performance.

When to Know to Get a New Battery

The biggest sign of a battery that is nearing the end is that when fully charged, say after a long trip, that it slowly cranks the engine.  However, because the battery is a component of a larger system connected to other parts of the vehicle, a slow cranking may indicate a deep problem. If something else is going wrong in your electrical system — say, a weak alternator – and a functioning battery may be providing less current than it should. A mechanic can help check this for you. The battery itself can provide other clues to whether it’s on its way out. One of these is age. If your battery is older than three or four years, start to expect problems sometime soon.


Batteries are so simple, and usually reliable, that drivers have a tendency to forget they are even there until it’s too late. If you pay attention to the age of your vehicle’s battery, you will reduce your risk of being stranded on the road. All things considered, batteries are inexpensive, considering the amount of work they perform each and every time you turn on your car. When in doubt, it often makes sense to just get a new one after four or five years of use.