Layer Shape LiFePO ₄ Obtained by Powder Extrusion Molding as Solid Boosters for Ferro/Ferricyanide Catholyte in Semisolid Redox Flow Battery: Effect of Porosity and Shape

Powder extrusion molding is proposed to fabricate ceramic LiFePO4 layers (0.5–1.0 mm thickness) as solid booster for ferricyanide electrolyte in semisolid redox flow battery. In some extruded layers, the binder partially decomposed, while others it completely removed and, afterwards, material sintered, so materials with different porosity and dimensions are obtained. After characterizing materials, kinetics reaction evaluated, being binder-less ones which react faster reach larger degrees of oxidation. For 1.0 thick comparable results already published obtained (69 % capacity compared theoretical value). case 0.5 sintered solid, an outstanding performance achieved, reaching almost (94 %) a very high coulombic efficiency (>99 at 1 mA cm−2, that were only much lower current densities previous works.