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Auto Battery Maintenance

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To get the optimal performance, power and reliability you expect from your car battery, it needs regular maintenance. By knowing the basics of how your battery works and following the simple steps to maintain it, you'll get dependable starting power and peace of mind.

How does a battery work?

A battery stores energy in chemical form that can be released on demand in the form of electricity. This electrical power is used by the vehicle's ignition system for cranking the engine. Lights and other accessories in the vehicle also rely on the battery as a source of power. Should the alternator or belt fail, the battery might also need to power the vehicle's entire electrical system for a short period of time.

When you turn the key in your vehicle's ignition, a circuit is completed and then energy that is stored in chemical form is released as electricity. This electrical power is used to activate the starter, which cranks the engine. The battery also supplies power to the vehicle's lights and other accessories.

Batteries need to be tested on a regular basis, including when you have your car serviced, before long trips or after it has been recharged.

You also need to maintain all areas of your vehicle as directed in your owner's manual and by your mechanic. This will reduce the chance of other engine components draining power from your battery.

Although battery damage occurs in warm conditions, it is important to remember that most batteries fail in cold weather. Hot temperatures will accelerate battery deterioration by evaporating the water from the electrolyte and causing grid corrosion, but the cold winters months are when you're most likely to feel the impact of the damage.

Battery safety and handling

Lead-acid batteries contain hydrogen-oxygen gases than can be explosive and sulfuric acid that can cause severe burns.

To avoid the risk of danger and injury:

  • Follow the safety instructions on the battery when handling or working with it.
  • Safety glasses should always be worn to shield the eyes.
  • Never lift or handle a battery by its terminals.
  • Always keep away from sparks, flames and smoking.
  • Always consult your vehicle and/or battery owner's manual for additional instructions and safety precautions.

Watch for warning signs of battery Failure

There are signs you can watch for while driving your vehicle that will indicate potential battery failure:

  • Hard/slow starting
  • Electrical components that don't function properly (door locks or windows, defrosters)
  • Trouble lights on the dashboard
  • Dimming of interior or headlights

These warning signs could all lead to the unwelcome event of a dead battery.

What are the most common causes of premature battery failure?

  • Deep discharges
  • Misapplications
  • Using an undersized battery
  • Loss of electrolyte due to under-hood heat or overcharging
  • Undercharging or malfunctioning alternator
  • Excessive vibration (due to lose hold down clamp)
  • Corrosion
  • Freezing (any fully-charged battery will not freeze until the temperature is -75°F)
  • Drain on your battery when your vehicle is turned off. Check accessories including cell phones, GPSs, TVs or computers. Even car alarms can impact your battery.
  • Leaving your headlights, dome light, glove box light or trunk light on for a long period of time
  • Extremely hot or cold temperatures can take a toll on the battery's charge
  • An electrical short anywhere in the vehicle
  • Modifications to the vehicle with air conditioning, power boosters, additional accessories or electronics
  • Failure to charge a battery during a period of 6 months or more

If you do have to park your vehicle for longer periods of time, (weeks or months), it is best to disconnect the battery to prevent discharging. Use a crescent or open-ended wrench to loosen the strap from the negative terminal on the battery, and then remove the connector. Make sure the connector is tucked away from the terminal, where it cannot come into contact with the post.

Did you know?

It's not always the battery's fault when a car doesn't start! It's important to remember that a vehicle that won't start doesn't necessarily stem from a dead battery. To determine why your car won't start, check your battery's condition first. You could have a bad starter or solenoid - or your alternator could be defective. The problem could also be a result of something around the battery.

Your terminals or battery clamp could be corroded or you could have a loose ground wire causing intermittent connection. If your battery is not installed correctly or if it's the wrong size it can vibrate excessively and result in internal damage to the battery. Your battery could also be discharged, which simply means it needs recharging.

What should you consider when buying a battery?

Even with good maintenance, your car battery may need to be replaced several times during a vehicle's lifetime.

When it's time to purchase a new battery, consider:

What are the dimensions of your original battery?
What are the cold cranking amps required to power your vehicle? Warranty: automotive batteries are backed by a warranty package. Chose what is right for your vehicle's needs.

If you know the basics of how to properly maintain your vehicle's battery, you can be sure it will last longer, give you greater peace of mind, and help you to avoid the inconvenience of a dead battery.