Even if you're driving a gas guzzling SUV, electricity remains crucial to driving a car. Thanks to modern-day electric batteries, drivers no longer have to turn an engine over by hand. It now all happens with the turn of a key or a press of a button.
But beyond that initial ignition, the battery continues playing a vital role in all of your vehicle's electric systems, but some myths have circulated about this electric heart pulsating in all our autos. Here's a thorough examination of those myths and some some cold, hard facts to replace them.
Battery Life (and Death)
A car battery should last about six years, but like most car parts, that all depends on how you treat it. Multiple discharge/recharge cycles shorten any battery's life and using electronics in the car while the engine is the quickest route to a dead battery. Of course, a battery can maintain a charge while the engine is on, but once it's off electronics draw directly from the battery.
To avoid this recurring auto nightmare, always turn the headlights and interior lights off when you're done driving. Remember that leaving electronics like GPS or cell phones plugged into a car charger can drain the battery, too.
No matter how well you take care of it, eventually your battery will die and you'll need a replacement. Failing batteries usually display obvious symptoms that let you know it's on its way out. Slow cranking on startup indicates that the battery may not be able to provide enough power to fire up the engine, and an illuminated Battery Warning Light on the dashboard is clear indicator it needs attention. If vehicle electronics like remote locks or interior lights randomly stop working, a dying or dead battery could be why.
Also, batteries—alive or dead—are full of chemicals, so do nature a favor and dispose of dead ones properly. Don't just toss it in the trash because chances are your local mobile mechanic or auto supply store can recycle it for you.
Ambient temperature has a significant impact on battery life and performance. Most car batteries use a liquid electrolyte solution to hold a charge, which is affected by hot or cold weather. While it takes extremely low temperatures to freeze a battery, cold reduces the solution's ability to transfer full power (which is why it can be hard to start a car in winter). There's a misconception that buying a battery with a higher CCA (cold cranking amp) rating will remedy this, but since vehicle computers regulate the amperage required for startup, it actually won't make any difference. Use a battery heater instead – it's like a toasty jacket that will keep your battery warm and reliable all winter.
On the flip side, hot weather can cause the battery solution to evaporate, limiting its ability to hold a charge. You may notice a rotten egg smell from the sulfur in the solution if this happens. A common myth is that you can simply refill it with tap water to make up for evaporation, but tap water contains minerals and impurities that can damage battery cells. Use deionized or demineralized water instead, but if you have to do this it's probably a sign that you need a replacement soon. Keeping your car garaged helps the battery cope with temperature extremes so it lasts longer and works more reliably.
Source : http://www.popularmechanics.com/cars/technology/a26549/car-battery-how-to/