This disclosure details exemplary home energy storage systems capable of storing electricity locally for later consumption, such as for charging an electrified vehicle, supporting various home energy needs, and supporting alternative energy storage/power source functionality. An exemplary home energy storage system may include a stationary unit, one or more modular units removably connectable to the stationary unit, and a rack mounting and handcart transportation system configured to mount, detach, and transport the modular unit relative to the stationary unit. Once undocked from the stationary unit, the modular unit(s) may be utilized as a portable power source for powering one or more electrical loads. This disclosure further describes various interconnected functionalities (e.g., electrical and wireless communication of state of uses) between the stationary unit and the modular unit of home energy storage systems and between the modular unit and various satellite equipment associated with the modular unit.