US Patent 10461545 Battery system

In a battery system that connects a plurality of types of batteries through a switch SW, when the switch SW is switched at a voltage (charge rate), it has been possible to increase a stored charge during charging, depending on the DC resistance of the battery. An object of the present invention is to provide switch SW switching control so that the stored charge can further be increased. A first feature of the present invention is to provide a battery system in which a first battery and a second battery are connected in parallel through the switch SW, including an estimator which estimates the charging current by measuring the resistance and OCV of each battery. The battery system can further increase the stored charge by switching to a switch SW combination that can increase the stored charge.