A system includes a first energy storage device, a second energy storage device coupled to the first energy storage device and charged via a charging current from the first energy storage device, a power controller having a processor, a memory coupled to the processor and on which charging current instructions are stored, and a converter coupled to the processor and directed via switch control signals from the processor, and an output terminal via which power is provided to a load of the system. The converter is disposed between the first energy storage device and the output terminal. The converter is disposed between the first and second energy storage devices and configured to control a level of the charging current in accordance with the switch control signals. The charging current instructions are executed by the processor to cause the processor to generate the switch control signals such that the level of the charging current is regulated.