VEHICLE-TO-VEHICLE CHARGING UNIT AND PROCESS

A charging unit for use by a charge-receiving electrical system (“recipient”) and a charge-providing electrical system (“donor”) includes a housing and an auxiliary battery. A bi-directional, buck-boost high-voltage (HV)-to-HV converter is connected to an HV bus between disconnect devices. A bi-directional, buck-boost HV-to-LV converter is connected to the HV bus and a low-voltage (LV) bus. A supply equipment communication controller (SECC) detects charge port control signals and establishes communication between the SECC and a system controller. Separate donor and recipient monitoring circuits determine an isolation state of the HV bus and a state of the disconnect devices. During the charging process, the system controller selectively commands offloading of a charging current from an energy storage system of the donor, through the HV-to-HV converter, and to an energy storage system of the recipient.