US Patent 8040106 Method of controlling battery charging

The present teachings are directed toward methods of controlling the charging of a battery. The method includes the steps of receiving current and voltage output information for the battery during a charging/discharging cycle at a certain time interval, and using a model to determine both charging efficiency of the battery and the overpotential for a side reaction. These values for the charging efficiency and the overpotential of the side reaction are then compared to respective first and second given values. If either the charging efficiency or the overpotential is less than their respective given values, then the charging of the battery is suspended. The present method is particularly applicable to Li-ion batteries.