Batteries are an important part of any vehicle because they start the engine and operate electrical parts. Such as the ignition system, lights, wiper motor, AC/heater blower motor, radiator fan motor, radio, and sensors.
But sometimes, when the battery becomes old, the problem of corrosion of the battery terminals starts, due to which the terminal or connector wire of the battery starts getting damaged and the supply of battery output current starts disappearing.
In this article, we will learn about battery terminal corrosion in detail. Such as what is battery terminal corrosion, its causes, how to clean it, and how to prevent it?
What Is Battery Terminal Corrosion?
Battery terminal corrosion is a white or blue-green powdery substance on the metal terminals. It is deposited due to a chemical reaction between the sulfuric acid and metal terminals of the battery.
Battery terminal corrosion can disrupt the flow of electrical current through the vehicle’s electrical system, causing problems with engine starting and charging as well as corroding cable connectors. Regular battery cleaning, maintenance, and application of anti-rust compounds can help prevent this problem.
Why Does Battery Terminal Corrosion Occur?
Corrosion of any battery terminal occurs when the metal terminals on the battery, usually lead-acid, react with environmental factors such as moisture, sulfuric acid vapor, and contaminants in the air.
Reactions between the metal terminals and sulfuric acid form a white, green, or blue substance called battery terminal corrosion, which can interfere with the flow of electrical current between the battery and connected components.
What Causes Corrosion On Battery Terminals?
Common causes of battery terminal corrosion may be leakage of battery electrolyte, overfilling the battery, overcharging the battery, chemical reaction with metal, battery age, or leakage of hydrogen gas.
Let us know the causes of battery terminal corrosion in detail so that you can have complete information about its maintenance and cleaning.
1. Over Filling Battery
The operation of many types of batteries in vehicles is based on water. This type of battery needs watering from time to time. That’s why sometimes the battery gets overfilled while adding water.
Due to this, water starts to flow out through the vent when the battery is shaken and due to the water mixing with the acid, it comes into contact with the battery terminal. Due to which rusting starts on the battery terminal.
2. Battery Overcharging
To get power from the battery in any vehicle, it needs to be recharged. This allows the battery to be fully energized and provide power to the electrical components of the vehicle. Because of this, an alternator is provided in the vehicles to charge the battery simultaneously.
The alternator charges the battery when it rotates with the engine. But sometimes the alternator starts overcharging the battery due to a faulty charging regulator on the alternator.
Due to this, the liquid starts leaking from the root of the positive terminal pole of the battery and this leakage starts reacting by coming into contact with the copper clamp on the positive terminal of the battery. Due to this, rust starts at the positive terminal of the battery.
3. Leakage Battery Electrolyte
Sometimes the battery used in vehicles breaks the surface of the battery by rubbing it with something, or the plastic surface of the battery cracks, due to which the fluid of the car battery starts leaking and the electrolyte coming out of the battery starts reacting with the terminal, due to which a blue, green, or white color starts to rust on the terminal of the battery.
4. Metal & Chemical Reaction
Copper is a good conductor metal for electric current. and resists corrosion well. However, copper sulphate is then produced.
When electric currents flow through the copper terminals, the battery terminals corrode. The presence of a blue precipitate on the copper terminals may be Copper Sulphate.
5. Battery Age
Battery life can also occur due to corrosion at the terminals of the battery because the leakage of fluid from the battery is a definite process when the battery is too old.
And the electrolyte fluid from the battery reacts when it comes in contact with the metal terminal, due to which corrosion starts at the terminal of the battery.
6. Hydrogen Gas Leakage
Common batteries used in vehicles convert acid into electric current, which reacts between the fluid and the internal components of the battery.
During this process, hydrogen gas is formed inside the battery and hydrogen gas finds its way out from somewhere and this hydrogen gas reacts with the battery terminal, which is made of metal. Due to which corrosion starts appearing on the battery terminal. The battery problem can be detected by looking at which terminal of the battery is corroded.
The corrosion appearing on the negative terminal of the battery may be due to low charging of the battery and the corrosion seen at the positive terminal is due to overcharging.
How To Clean Battery Terminals Corrosion?
You can clean battery terminal corrosion in three ways:
- With simple hot water
- With baking soda water solution
- With corrosion cleaner
NOTE – Before cleaning battery terminal corrosion, it is important to take care of your safety as the battery contains acid electrolyte fluid and the rust visible on the battery terminal is also a kind of chemical substance. Battery fluid or corrosion reacts rapidly when it comes in contact with our skin and can cause skin irritation or damage.
That’s why you should wear gloves on your hands before doing any work related to the battery of the vehicle and don’t let battery fluid or corrosion get on any part of the body. This can be harmful for you.
1. Cleaning With Simple Hot Water
You can easily clean the corrosion from the battery terminals with hot water because hot water mixes with the battery terminal corrosion to melt the corrosion, due to which the corrosion is easily cleared. In this process, first pour hot water on the corrosion on the terminal connector. After this, open both terminals of the battery.
Scrub the positive and negative poles of the battery with a toothbrush and hot water, and keep adding hot water. After this, dip the copper terminal and wire end in hot water, too, and scrub them completely with a toothbrush.
After this, clean the battery pole and terminal thoroughly with a clean cloth and fit the terminal. You can then apply grease to the terminal.
2. Cleaning With Baking Soda Water Solution
In this process, prepare a solution of baking soda and water. And you can use a toothbrush. To clear battery terminal corrosion, first turn off the vehicle’s ignition.
First of all, carefully remove the battery terminal. Now pour a solution of baking soda on the positive and negative poles of the battery and scrub with a toothbrush. Add this baking soda solution again and clean it by rubbing it well.
After this, clean the battery terminal and the ends of the main positive and negative wires from the terminal and clean them with a baking soda solution, then scrub it off with a toothbrush.
After cleaning, fit the battery terminal tightly. You can use grease on the terminals of the battery to prevent further damage.
3. Cleaning With Corrosion Cleaner
First, remove the battery terminal and the positive and negative connecting cables. Spray the corrosion cleaning product onto the battery until you remove the corrosion over the entire affected area.
With thick rubber gloves, use your wire brush to scrub the area until the rust is removed. Take out the battery and clean the battery case as well.
After cleaning, re-tighten the battery terminals and connector cables properly. Thereafter, grease is applied to the battery terminals to prevent future corrosion.
How To Prevent Battery Terminal Corrosion?
- Always check the battery from time to time.
- Never overcharge the battery.
- Never overfill the battery.
- Replace the damaged battery.
- Use copper terminal clamps.
- Always apply grease to the battery terminals.
Battery Terminal Replacement Process
There are several steps to replacing a battery terminal.
- First, disconnect the cable from the negative terminal of the battery. For this, remove the damaged terminal by loosening the bolt or clamp.
- Next, clean the battery terminals and cable ends with a wire brush.
- Next, install the new terminal tightly and securely onto the battery. Finally, disconnect the battery cables from the positive terminal.
- Next, make sure that all connections are tight and secure.
- Follow safety precautions, wear protective gloves, and consult your vehicle’s manual before replacing the battery terminals.
Banty is the owner of Autorepairszone.com & is also a vehicle mechanic by profession. We have almost 12 years of experience in the field of automotive repair, and we strive to provide you with accurate information about vehicle malfunctions and repairs based on our experience.