Alcohol Diffusion in Alkali-Metal-Doped Polymeric Membranes for Using in Alkaline Direct Alcohol Fuel Cells

Abstract

The alcohol permeability of anion exchange membranes is a crucial property when they are used as a solid electrolyte in alkaline direct alcohol fuel cells and electrolyzers. The membrane is the core component to impede the fuel crossover and allows the ionic transport, and it strongly affects the fuel cell performance. The aim of this work is to compare different anion exchange membranes to be used as an electrolyte in alkaline direct alcohol fuels cells. The alcohol permeability of four commercial anion exchange membranes with different structure were analyzed in several hydro-organic media. The membranes were doped using different types of alkaline doping agents (LiOH, NaOH, and KOH) and different conditions to analyze the effect of the treatment on the membrane behavior. Methanol, ethanol, and 1-propanol were analyzed. The study was focused on the diffusive contribution to the alcohol crossover that affects the fuel cell performance. To this purpose, alcohol permeability was determined for various membrane systems. The results show that membrane alcohol permeability is affected by the doping conditions, depending on the effect on the type of membrane and alcohol nature. In general, heterogeneous membranes presented a positive correlation between alcohol permeability and doping capacity, with a lower effect for larger-size alcohols. A definite trend was not observed for homogeneous membranes.

Boosting Power Density of Proton Exchange Membrane Fuel Cell Using Artificial Intelligence and Optimization Algorithms

“…Different types of membranes offer various characteristics and suitability for different applications, leading to the classification of FCs based on their specific membrane technologies. FCs encompass a variety of types, including high-temperature PEM-FCs [24,25], direct methanol FCs [26,27], solid oxide FCs [28,29], alkaline FCs [30,31], microbial FCs [32,33], direct ethanol FCs [34,35], phosphoric acid FCs [36,37], molten carbonate FCs [38], regenerative FCs [39,40], direct alcohol FCs [41,42], enzymatic FCs [43,44], direct ethylene glycol FCs [45], direct carbon FCs [46,47], and more. PEM-FCs are particularly preferred in the automotive sector due to the characteristics of the membrane used in their construction.…”

Membranes for Energy Conversion

“…Six of these published papers focus on membranes themselves as a key part of energy conversion systems [ 1 , 2 , 3 , 4 , 5 , 6 ]. The issue of proton-exchange membrane degradation in fuel cells was analyzed by Robert at al.…”

“…Therefore, the design of new membranes with low alcohol diffusion for these applications is vital. In this context, Fernández-Nieto et al [ 5 ] studied the alcohol diffusion of several anion-exchange membranes doped with different alkaline agents and showed that the membrane structure, type of doping, and type of alcohol affected this crucial property.…”