The device is everywhere advertised as being able to charge and restore any battery. In fact, it can only work properly with fresh and good elements. As an example, nimh aa element from gp at 1600mah, discharged to 1v This device refuses to detect it. You insert it into the charger from gp 20 years ago, charging went. And only when it is charged up to ~ 1.2v, this charger begins to determine it.