Materials for fuel-cell technologies

Abstract

Fuel cells convert chemical energy directly into electrical energy with high efficiency and low emission of pollutants. However, before fuel-cell technology can gain a significant share of the electrical power market, important issues have to be addressed. These issues include optimal choice of fuel, and the development of alternative materials in the fuel-cell stack. Present fuel-cell prototypes often use materials selected more than 25 years ago. Commercialization aspects, including cost and durability, have revealed inadequacies in some of these materials. Here we summarize recent progress in the search and development of innovative alternative materials.

Study on Electrical conductivity and Activation Energy of doped Ceria nanostructures

“…Thus research is going on to reduce the operating temperature of SOFC that require solid electrolyte, major component of SOFC, with high ionic conductivity even at low or intermediate temperatures (~600 ∘ C-800 ∘ C). Samarium doped ceria (SDC) and gadolinium doped ceria (GDC) exhibit higher conductivity than YSZ at 700 ∘ C [2,3]. Apart from that it is possible to obtain power densities as high as 1 W/cm from anode-supported SDC fuel cells at 600 ∘ C using hydrogen as the fuel and air as the oxidant.…”

Chemomechanics of ionically conductive ceramics for electrical energy conversion and storage

“…As a result, reduced system sizes can have profound effects on the performance and electro-chemo-mechanical phenomena in both systems. In fuel cells, thin film electrodes and electrolytes decrease the overall resistance of the cell; this scale reduction can also reduce operating temperatures [8,12]. Another consequence of using thin films in fuel cells is the production of steeper oxygen partial pressure gradients, and therefore lattice parameter gradients, across membranes, potentially giving rise to strains that could change the other properties of the materials.…”

Estudio comparativo de las diferentes tecnologías de celdas de combustible

“…De acuerdo a algunos investigadores, esto significa que electrolitos de YSZ con un espesor muy pequeño, pueden superar al LSGM en celdas de que operan a temperaturas intermedias con un espesor de 15μm. Cabe resaltar que el LSGM también puede formar segundas fases a bajas temperaturas como los compuestos SrLaGaO 7 y La 4 Ga 2 O 9 , en los límites del electrolito 60 .Es importante resaltar que una alternativa son las celdas micro-tubulares de óxido sólido, las cuales han demostrado interesantes propiedades para aplicarse en sistemas de vehículos futuristas 61 .…”