Investigation of the effects of compression pressure on direct methanol fuel cell

Compression pressure has significant influence on the performance of direct methanol fuel cell (DMFC) and the effect of compression is more significant for a DMFC than a proton exchange membrane fuel cell (PEMFC). But there are few data concerning the compression pressure on the performance of DMFCs. Loading history and feeding mode may also affect the optimal compression pressure for the DMFC. This paper investigates the influence of compression pressure on the DMFC. The effects of reload and air feeding mode are also examined. The optimal pressure of the DMFC is 1 MPa when the cell is assembled for the first time in forced convection mode. However, the optimum pressure decreases to 0.05 MPa when the cell is compressed again because of the residual strain of the GDL. The optimal pressure decreases to 0.5 MPa when the cell operates in air-breathing mode. Therefore, the optimum compression pressure for a DMFC strongly depends on the loading history and the feeding mode.