Chemically stabilised extruded and recast short side chain Aquivion® proton exchange membranes for high current density operation in water electrolysis

Durability of a recombination catalyst-based membrane-electrode assembly for electrolysis operation at high current density

“…Polymers [34]. This membrane was purified in concentrated sulfuric acid and subsequently in distilled water before its use as separator for the electrodes in a zero-gap configuration PEM electrolysis cell.…”

“…The capability of the PEM system to work under asymmetric pressure conditions (by pressurising only the cathode compartment) reduces the corrosion of the metallic components at the anode and the hazards of fire and explosion due to the presence of pressurised oxygen [33]. On the other hand, hydrogen permeation towards the anode compartment, may cause, especially at low partial loads (below 20%), the risk of flammability occurrence [27,31,[34][35][36][37]. At low current density, the hydrogen concentration in the oxygen stream is usually high and a shutdown of electrolyser is required for safety reasons when this concentration reaches 2-3 % vol.…”

“…Beside the safety aspects, relevant efforts have been also addressed to reduce the costs of electrolysers by focusing on system operation at higher current density and on the use of lower amounts of precious metals [34,36,[43][44][45]. PEM electrolysers can effectively operate at high current density (4 A⋅cm -2 ) while keeping cutting-edge efficiency [34]. This allows maximising the hydrogen production rate thus reducing capital costs.…”

“…At high current density, ohmic losses are prevailing in the polarisation curves causing relevant efficiency decrease [3,6]. Ohmic losses can be reduced by using thinner membranes to achieve a voltage efficiency gain [26,34,36,44]. Benchmark membranes for PEM electrolysis are usually thicker than 100 µm (e.g.…”

Composite Nafion-CaTiO3-δ Membranes as Electrolyte Component for PEM Fuel Cells

“…In a typical low temperature PEMFC design, the perfluorosulfonic acid polymers are the state-of-the-art for solid electrolytes [ 3 ]. The most used polymer for these devices is Nafion®, manufactured by DuPont, due to beneficial features, such as high proton conductivity under fully hydrated conditions, suitable mechanical properties, high chemical and electrochemical stability, low fuel permeability, and electronic insulation [ 4 , 5 ]. In general, the proton conductivity of these membranes is approximately ~10 −1 Scm −1 at room temperature and under fully hydrated conditions.…”