A working battery is necessary for a vehicle to run. The battery gives a car its starting power as well as the electricity for additional electrical features like the windows or audio. You should keep your battery in good shape.
Regular inspections will enable you to identify issues early and address them as quickly as feasible. so, the question is, what causes battery terminal corrosion?
The most frequent reason for battery terminal corrosion is a chemical reaction between the battery acid and the metal of the terminals. On your battery terminals, corrosion often appears as a flaky layer of brown, white, or green discoloration.
The color of the deposit that has accumulated on your terminals should be noted since it differentiates between sulfation and corrosion.
Even though the discharge from these two processes resembles one another somewhat, corrosion and sulfation differ significantly in a few important ways. When battery acid interacts with the metal terminals, corrosion results.
It comes in shades of brown, white, or blue/green. Sulfation results when crystals of lead sulfate accumulate on the battery terminal as a result of the battery failing to hold a charge. Typically, it has a gray color.
What causes battery terminal corrosion?
Here are the most common causes of battery terminal corrosion:
- Chemical Reaction with Copper Clamps
- Overfull Battery
- Overcharging
- Battery Fluid leakage
- Aging battery
Chemical Reaction with Copper Clamps
Copper is frequently used to make the clamps used to connect your battery’s cables. When sulfuric gases from a battery interact with the current passing through the clamps, they can ignite a chemical reaction.
As a result, copper sulfate is produced, which might result in corrosion. Corrosion can appear on battery terminal clamps.
Overfull Battery
Water is required for the operation of some refillable batteries. Overfilling, however, may result in extra water escaping through the vents. Corrosion may happen if water comes in touch with the battery terminals.
Overcharging
Too much time spent charging a battery might result in excessive temperature rise and electrolyte expansion which can cause battery terminal corrosion. During this process, pressure is created, and it needs the means to escape. Vents allow electrolytes to escape, which can lead to corrosion buildup on the terminals.
Battery Fluid leakage
Battery damage might result in fractures or holes appearing that can let battery fluid leak. The accumulation of battery electrolytes on the terminals can then result in corrosion.
Aging battery
Sometimes something as simple as aging is the root cause of corrosion buildup. While most automotive batteries are meant to last for five years, deterioration around this time is typical.
How can one tell when a car battery terminal is failing?
Here are the most common signs and symptoms of a failing battery terminal:
- Trouble starting the vehicle
- Corroded battery terminal
- Loss of electrical power
Trouble starting the vehicle
One of the common signs of a problem with the battery terminals is difficulty starting the car. Corrosion along the battery terminals may obstruct the connection and make it difficult for the car to start.
Corroded or even loose battery terminals may be to blame for this. When the key is turned, the car may have trouble starting, crank slowly, or click quickly.
Corroded battery terminal
Visible corrosion is one of the most typical signs of a battery terminal problem. The terminals are vulnerable to corrosion since they are in close contact with the battery and are therefore exposed to the battery acid’s acidic fumes.
The battery terminals’ ability to conduct power may be hampered by corrosion, which in extreme situations may even entirely obstruct the flow. If there is a problem, it can be found by carefully examining the termination and the cable for any indications of powdery white or blue corrosion.
Loss of electrical power
The loss of electrical power is another typical sign of a damaged battery terminal. This usually occurs when a terminal is extremely rusted or has broken. A badly corroded or broken terminal that does not make proper electrical contact may cause total loss of power.
Terminals with this much corrosion will often need to be replaced. Battery terminals are a fairly straightforward and affordable part, but they do have a significant impact on the electrical system of the car as a whole.
How to clean battery terminal corrosion?
Make sure you have everything you’ll need before you begin to clean corrosion from your automobile battery. Make sure you have the necessary safety equipment and consider getting a respirator as well. A small amount of baking soda and water will also work.
How to clean battery terminal corrosion with cleaner:
- Take out the connecting cables (first black, then red).
- Spritz the cleaning solution onto the battery until the entire impacted region is covered.
- Use your wire brush to clean the area until the rust is gone while wearing thick rubber gloves. Make sure you get the battery case as well!
- Close the hood after reattaching your cables in the reverse order (first red, then black).
How to clean battery terminal corrosion with baking soda and water:
- Take out the connecting cables (first black, then red).
- Apply baking soda to the entire corrosion-affected area. Battery acid will be neutralized in this way.
- A small amount of water must be added to activate the baking soda and trigger a chemical reaction that will remove the corrosion.
- Using a paper towel, wipe the area clean and dry. A scrub sponge should be used to remove any leftover grime.
- Then, in reverse order (first red, then black), reattach the cables, and then close the hood.
How to Clean Battery Corrosion: Step-by-Step
Step 1: Start with safety. The powdery buildup around your battery’s terminals is caustic and can damage your skin and eyes. Wear heavy-duty gloves and eye protection while handling battery corrosion, and immediately wash away any corrosive material that gets on skin or clothing.
Step 2: Disconnect the battery. Starting with the negative terminal, carefully release the cable from the battery. Safely position the cable away from the terminal, these things are built to deliver the cable directly to the battery and are susceptible to ‘slipping’ back into place. Next remove the positive terminal connection.
Pro Tip: Before disconnecting your battery, use a battery memory saver to save stored data and protect your car’s electrical system. Be sure to reference your vehicle’s owner’s manual for specific information on using a battery memory saver.
Step 3: Inspect the battery cables. Once the battery is disconnected, take a moment to inspect the cables. Is there fraying or corrosion where the cable connects to the terminal? Is the insulation dry or cracking? Damaged cables need to be replaced.
Step 4: Remove the battery from the vehicle. It’s possible to clean corrosion from a battery while it’s still in the vehicle, but the safest method for you, your battery and your vehicle is to remove it from the car and place it in a shallow bucket or pan to collect the corrosive material you’ll be washing away.
Step 5: Start cleaning. Now it’s time to neutralize and remove the car battery corrosion. Use a wire brush or scraper to remove any solid, powdery corrosion from around the terminals and dirt from the top of the battery casing. Brush the corrosion away and let it fall into the pan below.
Step 6: Neutralize. You have a couple of options to fully remove and neutralize the remaining corrosion:
- Battery terminal cleaner is a commercially available product designed to clean and neutralize corrosion from your battery. It’s a spray-on solution that changes color as it reacts with corrosion.
- Baking soda and warm water make for a good neutralizing solution to clean battery corrosion. Make sure to mix your solution, dip a rag and wipe corrosion away rather than dumping the solution over the battery top. This is to prevent solution from leaking into the battery cells and neutralizing the sulfuric acid inside.
Pro Tip: Don’t forget to clean the terminal ends that connect your battery to the cables. You can dip the ends in baking soda and water solution, or use a commercial battery terminal cleaner.
Step 7: Dry and polish. Using a microfiber cloth, dry the battery casing, posts and terminals. Use a terminal cleaning brush to remove any debris or coating from the terminals that may interfere with the connection.
Step 8: Replace and reconnect. Return the battery to its tray inside your engine and reconnect the terminals. This time, start by securely attaching the positive terminal to the cable, then finish with the negative terminal. Replace the battery hold downs.
Battery Terminal Corrosion Prevention
There are preventive measures you can take to help avoid battery terminal corrosion. These include:
- Invest in an anti-corrosive spray: There are a number of preventative sprays and brush-on compounds that can be applied to battery terminals and posts. Remember to disconnect the battery cables before applying.
- Coat with petroleum jelly or dielectric grease: These perform much like anti-corrosive sprays but can be more affordable alternatives. Remember to disconnect the battery cables before applying these as well.
- Avoid overcharging or undercharging: If your battery is overcharging, it’s important to take your car to an automotive technician who has the ability to check for electrical faults. Undercharging can occur if the battery is not receiving enough power to return it to a full state of charge.
- Perform routine checks: Like other important car parts, your battery should be checked often. Taking the time to inspect the condition of the battery and accompanying parts can help you catch corrosion early before it gets out of control.