Automatic Charging Methods for Portable Battery Operated Equipment

A properly designed charger for sealed lead batteries must not only control the current during normal charge, but it must also turn itself off or switch to a float condition when charge is complete; and it must be able to charge batteries which have a very high initial resistance because they have been overdischarged. Many different types of chargers have been developed in the effort to find one that is suitable, and several of them are described. The best results are obtained with a new solid-state charger described in this paper.