What happens to maintenance-free batteries over time?

Maintenance-free batteries, such as those commonly used in vehicles, are designed to minimize user intervention while still providing reliable power. Over time, even these batteries can experience corrosion at the terminals. This occurs due to chemical reactions between the lead plates within the battery and the surrounding electrolyte, which can lead to the formation of lead sulfate and other deposits that can build up at the terminals. This buildup can interfere with the electrical connections, leading to poor performance or failure to start.

While maintenance-free batteries are less prone to leaks and do not require regular watering like traditional batteries, they are not entirely immune to issues such as terminal corrosion. Regular visual inspections can help catch these issues before they lead to more significant problems. Understanding the phenomenon of terminal corrosion and the factors that contribute to it is essential for maintaining the battery's functionality and prolonging its lifespan.