Polymer electrolyte membrane history

The fuel cell has a proven history with solid oxide based systems. Recent needs for miniaturization have generated new ideas of fuel sources and structures. These include direct methanol fuel cells (DMFCs) and polymer electrolyte membrane fuel cells (PEMFCs). These fuel cells have advantages over others for several reasons. A key quality is the potential energy that the fuel sources provide with respect to the fuel costs. 

The history of research on polymer electrolyte fuel cells spans about 50 years. PEFCs appeared in the focus of scientific interest toward the end of the 1980s. Generally, PEFC design is simple and all the needed components are available on the market. Take two gas-diffusion electrodes separated by a polymer electrolyte membrane and clamp this membrane-electrode assembly between two graphite plates with channels for hydrogen and air supply—the cell is ready. 

Despite advancement in the development of direct methanol fuel cells (DMFCs), some restrictions still inhibit their large-scale commercialization. This chapter has discussed one of the primary constraints, that is, identification of appropriate membrane materials. Nafion membranes that dominate the market of polymer electrolyte membranes allow methanol permeation from the anode to the cathode side of a DMFC. This results in serious negative consequences. Three approaches have been pursued in order to resolve the methanol permeation problem. These include Nafion membranes modification, development of alternative membranes and provision of high activity anode catalysts or methanol tolerant cathode catalysts. All the three options have achieved certain degree of success in solving the problan. Of particular interest are the Nafion membranes modification and development of alternative membranes in which membranes with permeability values of 10 to 70 times lower than the pure Nafion membranes have been developed. In general, based on the tremendous research efforts being made to develop DMFCs membranes with the best qualities, we are optimistic that very soon the issue of methanol permeation shall become a history. 

The membrane electrode assembly (MEA) is a delicate component in low-temperature fuel cells based on polymer electrolyte membranes. Its condition is affected by many factors (1) selection and preparation of MEA materials (catalysts, supporting carbon powder, membrane materials, binder for MEA hot pressing, etc.), (2) history of MEA usage, (3) fuel cell operation parameters, and so on. The resulting MEA condition exerts a strong influence on the fuel cell performance, which is also a function of running time. 

Abstract This article outlines some history of and recent progress in perfluorinated membranes for polymer electrolyte fuel cells (PEFCs). The structure, properties, synthesis, degradation problems, technology for high temperature membranes, reinforcement technology, and characterization methods of perfluorosulfonic acid (PFSA) membranes are reviewed. 

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