Abstract: A distributed energy storage system includes a bi-directional rectifier configured to convert AC to DC and DC to AC, a battery pack connected in series with the bi-directional rectifier, the battery pack including a plurality of batteries connected in series, an inverter connected in series with the battery pack, wherein the inverter is configured to convert DC to AC, and a controller operatively connected to the battery pack and the bi-directional rectifier to control charging or discharging of the battery pack, wherein the controller is configured to determine that a level of charge in the battery pack is at or above a first threshold, and cause the battery pack to supply power to an electric utility grid that is connected in series to the bi-directional rectifier.