Electric circuit for use with lithium ion battery system for diagnosis of switching contacts in battery-powered road vehicle, has unit for generating and measuring voltage drop via resistance element

摘要

The circuit has a set of electrical switches e.g. positive and negative main contactors (10, 11) and loading contactor (12), connected at an input side and an output side of terminals of a battery control unit (31). The terminals are coupled with a measuring tap for generating measuring voltages with respect to a reference potential. An adjusting unit adjusts the measuring voltages to a predetermined voltage value, and/or a unit generates and measures a voltage drop via an electrical resistance element e.g. loading resistor (17), where the adjusting unit comprises an auxiliary circuit. An independent claim is also included for a method for diagnosis of switching contacts in a battery-powered road vehicle.