When a healthy battery is recharged, this lead sulfate is converted back to lead and sulfuric acid.

But in tired battery, the lead sulfate changes to a crystalline form that coats the battery’s lead plates reducing its capacity. This process is known as sulfation. It is a common occurrence in lead-acid batteries and a major reason for their failure.

The good news is that you can often reverse sulfation utilizing a specialized high-current, pulse that effectively breaks down the crystalline lead sulfate and turns it back into lead and sulfuric acid, thus cleaning the lead plates and restoring charge capacity.