The influence of stack clamping pressure on the performance of PEM fuel cell stack

The effect of gas diffusion layer (GDL) compression on fuel cell performance was experimentally studied in a 5-cell proton exchange membrane fuel cell (PEMFC) stack. Two stacks with different GDL compression, 15% and 30%, were prepared using SGL 10BC carbon-fiber felt GDL and Gore 57 series MEA The PEMFC stack with high GDL compression (30%) showed better performance than low GDL compression (15%) at all current ranges This implies that the decrease of contact resistance by high GDL compression affects more dominantly on the stack performance than the increase of mass transport resistance in the present stack configurations The degree of GDL compression also affected the stack stability. particularly, under the reformed gas conditions as anode fuel The stack with low GDL compression could not be operated at low reformed gas flow rates showing sudden decrease of stack voltage Hence, in case of reformed gas condition. GDL compression should be higher than the case of pule hydrogen for the stable stack operation and to enhance the gas utilization at anode (C) 2010 Published by Elsevier B V