PILs‐based Nafion membranes: a route to high‐temperature PEFMCs dedicated to electric and hybrid vehicles

Abstract

International audienceThis paper deals with the performance of anhydrous proton-conducting polymers obtained by blending modified Nafion^® membranes with proton conducting ionic liquids (PILs). It has been shown that the conductivities depend more on the PIL uptake than on its intrinsic conductivity. Conductivities at 130°C approaching those of current Nafion membranes at 80°C and 98% relative humidity were obtained with the best blends. These data allow considering MEA operating at 120-130°C based on membrane and electrodes incorporating these blends. This is clearly a positive feature for an implementation in hybrid vehicles powered by proton exchange membrane fuel cells (PEMFCs) operating above 100°C. Lastly, preliminary results for a PIL based on a half-neutralized diamine show an improvement in oxidation and, provided that the neutralization is optimized, a neat reinforcement of the Nafion membrane can be expected

Ionic Liquids and Their Hosting by Polymers for HT‐PEMFC Membranes

“…PCIL purity was then checked by NMR, using a Bruker WM 250 spectrometer operating at frequencies of 250 MHz for the 1 H and 235.3 MHz for 19 F. The samples were dissolved in CDCl 3 . Peak assignments of PCILs were carried out by reference to the starting amines and acids.…”

Modification of Nafion Membranes by IL-Cation Exchange: Chemical Surface, Electrical and Interfacial Study

“…• C as a result of water loss and/or to minimize other kinds of electrode/membrane surface interactions due to electrode or catalyst changes [13][14][15][16].…”

“…In this context, it should be pointed out the significant number of papers published in recent years dealing with original and modified proton-exchange membranes conductivity and permeability, which are considered key parameters for their applications in proton and methanol (DMFCs) fuel cells, respectively [16][17][18][19][20][21][22]; particularly, a reduction of around two orders of magnitude in the methanol permeability across Nafion/IL-modified membranes attributed to the decrease of the methanol crossover associated to the presence of the ILcation has already been reported [23]. However, a more reduced number of papers on surface study of both original and modified membranes are published, although membrane surface represents the interface between two different transport media, which can be solid/solid in the case of fuel cells or solid/liquid when supported liquid membranes (SLMs) or other electrochemical devices proposed for selective solute separation are considered [15,24,25].…”

Towards Extrusion of Ionomers to Process Fuel Cell Membranes

“…In addition, in the case of acidic ionomers, plasticizers of higher basicity than the previous ones, such as sulfonamide and imidazole, were tested. Imidazole would have a dual function (i) neutralization of the acidic functions, which increases the thermal stability of the ionomer [16][17][18][19] and (ii) strong interaction with the neutralized acidic functions, which should efficiently plasticize the ionomer.…”