Abstract: An active balancing and battery charging system for a battery including a plurality of packs made up of cells. An H-bridge circuit having a nominal system voltage as an input generates a square wave output to a plurality of step-down transformers each associated with a pack, where the plurality of step-down transformers provide an active balancing voltage of about the nominal pack voltage. Each pack may include a balancing transformer including a common primary coil receiving the active balancing voltage from the associated step-down transformer or the pack itself. The balancing transformer also includes a plurality of secondary coils each associated with the respective plurality of cells of the pack. A voltage induced in the secondary coils causes a discrete charge current to flow to any cells in the pack that are undercharged relative to other cells.

Abstract: Implementations of the present disclosure involve a method and/or system for charge balancing across one or more modules or cells of a large battery system. In one embodiment to balance the modules, the battery management system may monitor the voltage output of the one or more modules of the battery system during recharging of the modules and compare the measured voltages to a set cutoff voltage. When one or more of the modules meets or exceeds the cutoff voltage, the battery system may activate an energy dissipating device associated with the one or more modules that meets or exceeds the cutoff voltage to reduce the voltage output from those modules below the cutoff voltage before the recharging signal is reapplied to the modules. Through multiple iterations of monitoring, charging and reducing the energy from the modules above the target, the SOC of each module becomes balanced near or at the cutoff voltage.

Abstract: Implementations of the present disclosure involve a battery management architecture for a battery system involving a plurality of connected power units. In general, the BMS comprises one or more management sub-controllers connected serially to a master controller associated with the powered device. Each of the one or more management sub-controllers may be associated with a power unit of the battery, with each power unit included one or more battery modules or battery cells. Each of the one or more management sub-controllers in the BMS share a communication link to provide and receive information and instructions associated with the battery system. In general, the BMS of the present disclosure provides flexibility and modularity to the architecture of battery systems for customization of the battery system for a variety of uses and environments.