Trickle charging is a method used to maintain the charge of a battery by supplying a low, steady current. This technique is often employed for lead-acid batteries, such as those found in cars or backup power systems. The slow charge helps prevent the battery from discharging completely, extending its lifespan and ensuring it is ready for use when needed. This charging method is particularly useful for batteries that are not frequently used, as it keeps them at an optimal charge level without overcharging. Devices like battery maintainers or smart chargers are commonly used for trickle charging, providing a safe and efficient way to care for batteries.