Performance enhancement of direct methanol fuel cell using multi‐zone narrow flow fields

Abstract

New serpentine and spiral flow field configurations were developed to enhance the performance of direct methanol fuel cells (DMFCs). The new configurations are based on two primary concepts, namely, narrowing the flow field and partitioning the total active area of the fuel cell. Three flow channel heights of 0.8, 0.4, and 0.2 mm were investigated in serpentine and spiral flow fields. The main active area is considered a single zone and is partitioned into two- and four-zone designs while maintaining the total inlet mass flow rate of the reactant and oxidant. To determine the performance parameters of the newly proposed designs, a three-dimensional single-phase isothermal model was developed, numerically simulated, and validated through experimental measurements. The findings of the current study indicate that a serpentine flow field configuration with a channel height of 0.2 mm and two zones attains an enhancement of the net power density of 37% compared to a conventional single-zone design with a flow channel height of 0.8 mm. Similarly, for a spiral flow field design, the maximum net power density increased by 26% using a two-zone configuration with a channel height of 0.2 mm, in comparison to the conventional design of a single-zone and a flow channel height of 0.8 mm. The newly developed designs utilize the lower height of the flow fields to decrease the dimensions of the fuel cell stacks and reduce the material costs required.