METHOD FOR DETERMINING THE INTERNAL OHMIC RESISTANCE OF A BATTERY MODULE, BATTERY MANAGEMENT SYSTEM AND MOTOR VEHICLE

摘要

The invention relates to a method for determining the internal ohmic resistance of a battery module (100) comprising at least one battery cell, for example a lithium-ion battery cell of the type used in traction batteries of electric or hybrid motor vehicles, that is, in motor vehicles comprising drives that are at least partly or intermittently electrically driven. The invention also relates to a motor vehicle and a battery management system (160). The disclosed method comprises the determination of the internal ohmic resistance from measurements of voltage intensities. The invention is characterised in that the method comprises the serial connection of the battery module (100) to at least one other battery module (100) that is subject to a load current and comprises the measurement of voltage intensities in the battery module (100) before and after said connection. This allows a measurement of current and voltage intensities to take place significantly closer to real time and thus almost simultaneously, which in turn allows the determination of the actual wear condition of the battery module (100) to be improved and the durability of individual battery cells or of battery modules (100) to be predicted.