US Patent 10062928 Method for charging batteries

A method for charging batteries that have at least one metal electrode or at least one metal-based compound electrode includes applying a DC signal to the batteries and applying an AC signal to the batteries. The DC signal and AC signal may be combined as a composite signal, which is applied to the batteries, or may be applied to the batteries as separate, independent signals, during a charging cycle. As such, the DC signal serves to charge the batteries, while the AC signal operates to suppress, avoids or reverse the growth of dendrites in the batteries. As a result, the operating life of the batteries is extended, and the electrical storage capacity of the batteries is preserved.