Systems and related methods for supplying power to an implantable blood pump are provided. A system includes a base module and a plurality of energy storage devices. A first energy storage device is operatively coupled to the base module. A second energy storage device is operatively coupled to the first modular energy storage device. The energy storage devices are mechanically coupled in series, electrically coupled in parallel, and configured to provide redundant sources of power to drive an implantable blood pump.