Experimental Analysis of - 30°C Cold Start Process for an Automotive PEM Fuel Cell System

Proton exchange membrane fuel cell (PEMFC) system is considered as one of the most popular power sources because of its high energy density, fast dynamic response and zero pollution. However, the start-up at low temperature (e.g. - 30 °C) is still a major challenge for its wide application due to water freezing in Membrane Electrode Assembly (MEA). In this paper, a cold start test process in an environment cabin with auxiliary heat was carried out for a full power automotive PEMFC system, including normal operation, shutdown purge and cold start processes analysis from -30°C. Rated power of this stack is 100kW at the current density of 1.4A/cm² and relevant maximum output power can reach to 120kW. In order to reduce the damage of high potential to MEA, on-load purge with a current of 30A is conducted to removing extra water in stack for improving cold start ability. Based on corresponding control strategy, cold start was realized successfully within 110s. Low temperature not only affects the success of cold start for fuel cell system, but also plays a key role on the stack output performance and lifetime. Taking effective measures to rise the stack temperature rapidly is important to get cold start successfully and promote its durability. This work verified the effectiveness of system design and control strategy. Hoping to provide reference for the optimization of extreme low-temperature start control strategy.