Sulfation is a buildup of lead sulfate crystals and is the number one cause of early battery failure in lead-acid batteries.
Sulfation occurs when a battery is deprived of a full charge, it builds up and remains on battery plates. When too much sulfation occurs, it can impede the chemical to electrical conversion.
A buildup of sulfates can cause…
- longer charging times
- excessive heat build-up
- shorter running times between charges
- dramatically shorter battery life
- complete battery failure
All lead acid batteries will accumulate sulfation in their lifetime as it is part of the natural chemical process of a battery. But, sulfation builds up and causes problems when;
- A battery is overcharged
- A battery is stored above 75 degrees
- A battery is stored without a full charge
To prevent sulfation when a battery is stored, even if it’s stored at a full charge, a battery must be charged enough to prevent it from dropping below 12.4 volts. Applying this maintenance charge will prevent sulfates from building up. It’s also important to note that while we mentioned a battery shouldn’t be stored in temperatures above 75 degrees, for every 10 degrees above room temperature, the rate of self-discharge doubles.
There are two types of sulfation that can occur in your lead battery; reversible and permanent. Their names imply exactly the effects on your battery. If the problem is recognized early enough, it is possible to reverse the sulfation of a battery. However, doing so should only be done by someone with seasoned experience working with lead batteries, such as the retail outlet where your battery was initially purchased.
Permanent sulfation occurs when a battery has been in a low state-of-charge for weeks or months. While these can sometimes be salvaged, it is unlikely that restoration is possible.
The best way to prevent sulfation is to practice proper battery maintenance and follow charging best practices. While there are anti-sulfation devices available that will apply pulses to battery terminals to prevent and reverse sulfation on a healthy battery, they will not reverse the damage completely and are not always recommended.
Sulfation is the number one reason you should not store your battery with an empty charge. Once sulfation of the lead plates has occurred, reversing the effects is highly unlikely, so it is critical to take care of your batteries from the start.