Abstract: A battery management system (BMS) connected to a battery having a positive end and a negative end, the BMS also connected to a fast charger. The BMS includes: a battery management controller protection circuit board (PCB) configured to manage an operation of the battery; a charger controller PCB configure to control fast charging of the battery; and a fast charge contactor positioned between one of the positive and negative ends of the battery and the fast charger. No fast charge contactor is positioned between the other of the positive and negative ends of the battery and the fast charger. The BMS is configured to determine a location of an isolation fault by connecting and disconnecting one or more resistors.

Abstract: An Energy Management Unit (EMU) integrates the on-board charger (OBC) and battery management system (BMS) and optional DC-DC to behave like a lab based Electrochemical Impedance Spectroscopy (EIS) device. New high-bandwidth charge control schemes, together with new high-voltage system architecture, are disclosed. During vehicle AC charging, the OBC outputs current that sweeps across various frequencies (typically 0.1 Hz to 10 kHz), while the BMS samples the voltage and current to create the Nyquist Plot (Real Vs Imaginary Impedance) of battery cell parameters, without high frequency cell voltage samples (which is not cost feasible for mobility and energy storage applications).