TWO-LEVEL METHOD FOR THERMAL RUNAWAY DETECTION

A battery system includes a rechargeable energy storage system (RESS) having battery cells, and a battery controller network configured to execute two-level logic to detect a thermal runaway condition. The network includes RES S-embedded cell monitoring units (CMUs) electrically connected to a respective cell group, and measuring and wirelessly transmitting cell data. A battery control module (BCM) is in communication with the CMUs. Thermal runaway sensors are mounted on the CMUs and/or the BCM. A master controller connected to the BCM includes a thermal runaway detection algorithm configured to detect a thermal runaway condition occurring within the RESS. The BCM uses data from the CMUs and thermal runaway sensors to execute first logic level which determines when to wake up the master controller. The master controller, in response to receipt of a wakeup signal, executes a second logic level to execute the algorithm.