Non‐Fluorinated Polymer Composite Proton Exchange Membranes for Fuel Cell Applications – A Review

Abstract

The critical component of a proton exchange membrane fuel cell (PEMFC) system is the proton exchange membrane (PEM). Perfluorosulfonic acid membranes such as Nafion are currently used for PEMFCs in industry, despite suffering from reduced proton conductivity due to dehydration at higher temperatures. However, operating at temperatures below 100 °C leads to cathode flooding, catalyst poisoning by CO, and complex system design with higher cost. Research has concentrated on the membrane material and on preparation methods to achieve high proton conductivity, thermal, mechanical and chemical stability, low fuel crossover and lower cost at high temperatures. Non‐fluorinated polymers are a promising alternative. However, improving the efficiency at higher temperatures has necessitated modifications and the inclusion of inorganic materials in a polymer matrix to form a composite membrane can be an approach to reach the target performance, while still reducing costs. This review focuses on recent research in composite PEMs based on non‐fluorinated polymers. Various inorganic fillers incorporated in the PEM structure are reviewed in terms of their properties and the effect on PEM fuel cell performance. The most reliable polymers and fillers with potential for high temperature proton exchange membranes (HTPEMs) are also discussed.

Selectivity of Transport Processes in Ion-Exchange Membranes: Relationship with the Structure and Methods for Its Improvement

“…Ion exchange membranes (IEMs) are actively used in modern technologies, including water purification, concentration, electrochemical synthesis, and sensors [ 1 , 2 , 3 , 4 , 5 ]. Their use in fuel cells [ 6 , 7 , 8 , 9 ], in energy storage and conversion systems, e.g., metal-ion batteries [ 10 , 11 , 12 ], reverse electrodialysis [ 13 , 14 , 15 ], and redox batteries [ 16 , 17 , 18 , 19 ] has received the most attention in recent years. There are a number of other technologies in which ion-exchange membranes can also be used.…”

Nafion‐coated LiNi0.80Co0.15Al0.05O2 (NCA) cathode preparation and its influence on the Li‐ion battery cycle performance

“…Nafion, which is a sulfonated tetrafluoroethylene-based fluoropolymer-copolymer, is frequently used in energy conversion applications, primarily in proton exchange membrane fuel cells as a proton conductor due to its high chemical stability as well as superior proton conductivity. 32 Here in this research, the reason for using Nafion is its excellent ionic conductivity, high chemical stability, and serving as a protective layer on the NCA cathode. With these properties, Nafion can help to eliminate the propagation of microcracks by covering the NCA particles and inhibit the surface reactions.…”

Simultaneous improvement of ionic conductivity and oxidative stability of sulfonated poly(ether ether ketone) nanocomposite proton exchange membrane for fuel cell application

“…In this regard, the physicochemical properties should be taken into consideration on preparation of the membranes. Thermal degradation and membrane dehydration occur at elevated temperatures . Likewise, the attacks of radicals, which are formed during the operation of a PEMFC, cause the chemical/electrochemical membrane degradation .…”