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How to Care for Your Car Battery

How to Care For Your Car Battery

battery being filled with water

Your car’s battery tends to be neglected until there you have difficulty starting your car, and it is usually when the weather turns cold. Your battery needs to be inspected and tested throughout the year to ensure it will operate properly every time you need it to.

Summertime is usually when battery problems begin, but because the engine is easy to turn over, your car battery’s ailing condition goes unnoticed. Some things effected by heat include:

  • Extreme heat, along with the excess heat that develops in the engine bay, speeds up corrosion on battery terminals and cables.

  • The high temperatures cause water in battery fluid to evaporate, exposing internal battery grids to corrosion.

  • Your car’s battery strength diminishes along with high temperatures.

This dramatically affects your battery’s ability to start your car in cold temperatures. When the mercury dips below the freezing point, your battery is ⅓ less powerful than in warm weather, and below zero Fahrenheit, it has only half the strength it has in the warmth.

Proper care for your battery involves inspecting and maintaining it year-round.

  • Warning: Alway wear eye protection, long sleeves, and gloves when you are handling a car battery to prevent the possibility of battery acid causing you harm.

Part 1 of 3: Perform summer battery care

car battery with bulging sides

Step 1: Inspect your battery’s visual condition. If your battery’s case is cracked, leaking, or bulging from the sides or top, it needs to be replaced.

Note if there is corrosion forming on the cable ends or battery posts.

Clean the corrosion according to Method 3.

caps being removed from battery

Step 2: Check your battery’s fluid level. Not all batteries have caps to check the fluid level. If yours does not, skip this step.

Plugs or caps on the top of the battery seal the fluid inside.

Unscrew the plugs or pry the caps off to check the fluid level.

If the battery fluid is covering the vertical plates inside your battery, it doesn’t need attention.

If the plates inside your battery are exposed at the top, add distilled water carefully to your battery.

Add just enough water to cover the plates completely. The fluid will expand in hot weather and could push battery acid out the top of the battery if it is overfilled.

  • Warning: Only use distilled water to top up your battery fluid, never tap water.

Re-install the battery caps or plugs tightly.

car battery being installed into car

Step 3: Fully charge your battery. If you perform short trips or predominantly drive in the city, it’s possible that your battery doesn’t charge enough between your starting point and destination.

This can lead to a discharged battery over time, leaving you stranded or needing a boost.

Use an automatic battery charger such as the Schumacher SpeedCharge to top up your battery’s charge.

Attach the red lead to the positive (+) battery terminal and the black lead to the negative (-) terminal.

Select the highest rate of charge such as 12 amp, then plug the charger in. It will automatically adjust the rate of charge down, depending on your battery’s condition.

Wait until the charger indicates you have a full charge which can take several hours.

Disconnect the charger by first unplugging the unit then disconnecting each lead from the battery.

Part 2 of 3: Perform winter battery care

In the winter, your car requires twice as much battery power to start than it does in the summer. If your battery isn’t up to snuff, it can leave you stranded with a car that doesn’t start.

Step 1: Protect your battery from freezing. A fully charged car battery will only freeze at -76F, while a fully discharged battery can start to freeze at 32F.

Never let your car battery become fully discharged or it could freeze when the temperature drops.

A frozen battery not only won’t accept a charge but will potentially cause damage to your battery case or internal battery cells that require replacement instead of easy maintenance.

If you have a car battery not currently installed in your car, keep it in a spot that is not exposed to freezing weather such as a heated garage or basement.

Step 2: Keep your battery fully charged. Your car requires much more battery power to start in cold weather, and may need your battery to be fully charged to start.

During cold weather spells, put an automatic battery charger or a trickle charger on your car battery to maintain its charge level.

Step 3: Have your battery tested every 3-6 months. Bring your car or car battery to an auto parts store, many have bench testers or in-car battery testers to determine if your battery is failing or in good condition.

It’s usually a free service provided by parts retailers.

Part 3 of 3: Remove corrosion from your battery posts and cables

Materials Needed

wrench on battery cable end

Step 1: Disconnect your battery cables from your battery. Turn the cable clamp nuts or cable bolts counterclockwise to loosen them.

Wiggle the cable free from the top post when it is loose. If it is a side-post battery, completely unscrew the bolt.

Remove both battery cables from the battery at the same time.

battery brush inserted with arrows

Step 2: Insert the battery terminal brush over the battery post. Turn the brush to clean corrosion from the post. It will only turn one way.

Make two complete revolutions with the terminal brush, then take it off to check if all the corrosion is gone.

Repeat if necessary to clean all the corrosion from the post.

Do the same for both the negative and the positive post.

maintain car batteries

Step 3: Clean the battery cable end.

There is a stiff, brass-bristled brush under a cap on the terminal brush.

Take the cap off, then insert the brush into the battery cable end.

Turn the brush several times, reaming any corrosion from the cable until you see bright metal exposed.

Step 4: Re-install the battery cables onto the battery posts. Tighten with the terminal wrench until they are snug, then add another quarter turn to tighten.

yellow foam coverings

Step 5: Spray with battery cleaner. Spray the battery posts, battery case, and battery cable ends with battery cleaner spray.

Cover the battery completely with cleaner to neutralize battery acid that may have escaped.

Let the cleaner soak on the battery for only a minute, then rinse well with clean water.

If you notice anything wrong with your battery while you’re inspecting and cleaning it, make sure to have a professional mechanic check it out. One of our mobile mechanics from YourMechanic can service your battery or replace it at your home or office.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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