An energy storage unit (ESU) is provided herein. The ESU includes a housing forming an interior volume configured to store a plurality of batteries that can collectively provide a maximum power level. The ESU includes a segmented branch interconnect system including a power transfer assembly that includes a first power interconnect system and a second power interconnect system. The second power interconnect system is configured to be coupled to a first adjacent power interconnect system of a first adjacent ESU. The power transfer assembly includes one or more conductors coupled to the first power interconnect system and the second power interconnect system, and is configured to transfer electrical power therebetween. The power transfer assembly is rated to transfer a power level that is at least three times the maximum power level provided by the plurality of batteries stored in the housing.