An Energy Balance Model for a Direct Methanol Fuel Cell

Fuel cell is a kind of devices that generates electricity and heat via electrochemical reactions. Accompanying the development of relevant applications, the efficiency issue has received more and more interest. In the duration of electricity generation, a variety of polarization losses will disperse in the form of heat. Higher electricity efficiency leads to lower heat generation, and vice versa. The amount of the generated heat correlates with the temperature gradient of the fuel flow along the stack channel. For a direct methanol fuel cell (DMFC), both the fuel utilization efficiency and fuel concentration are essential indices for the system. However, it is much complicated to acquire them. As a result, it will be a feasible and valuable approach to correlate these indices with the temperature gradient. In this work, an energy balance model of a DMFC is established to investigate factors that contribute thermal influences on the system. Based on the model, the relationship between efficiency and temperature gradient is derived. The proposed model may serve as the basis of water and thermal management strategies, which are beneficial for enhancing the performance and reliability of such a power generation system.