A battery is crucial for the proper functioning of your vehicle. It powers the ignition, radio, headlights, AC, etc. However, it’s function could be impaired once the terminals start corroding. While you can clean a corroded battery, this article will discuss the causes and what you can do to prevent it.
What Is Corrosion?
Corrosion is a process where a refined metal is converted to its more stable oxide, hydroxide or sulfide. In batteries, it’s usually made up of lead sulfate and anhydrous copper sulfate (when the battery connectors are involved) and appears as a green, white, or blueish material found on the terminals.
This substance is a poor conductor of electricity and it increases the resistance in the circuit as a result. The higher resistance causes intermittent flow of electricity, leading to your vehicle not starting.
Why Does It happen?
There are plenty of reasons for this battery terminal corrision. Here are the major ones:
Undercharging
This is a major cause of corrosion on the negative battery terminal. It usually happens when a vehicle isn’t sufficiently driven, preventing it from taking in enough charge.
Overcharging
A more common cause of corrosion on the positive terminals, overcharging results in gas formation (especially hydrogen), which escapes via the vents of the battery. When the gas comes in contact with the positive terminals, it reacts with the metal, causing corrosion.
Bad Alternator
A faulty alternator could either overcharge or undercharge your battery leading to either of the above situations.
Overfilling the Battery
For batteries that require regular maintenance topping with distilled water, overfilling can cause excess water to escape through the vents. Corrosion could result when this water touches the battery terminals.
How to Prevent Battery Terminal Corrosion
While you can clean a corroded battery, it’s better to take preventive actions to lessen the risk of it happening in the first place. For example, you can spray special coatings like battery terminal protectors to help prevent corrosion. You can also apply battery grease or even vaseline to the terminals before connecting the leads. Any of these will keep acid, hydrogen, or oxygen gas released from the battery from coming into direct contact with the terminals.