The evolution of low temperature solid oxide fuel cells

Low temperature solid oxide fuel cells (SOFCs) are a promising solution to revolutionize stationary, transportation, and personal power energy conversion efficiency. Through investigation of fundamental conduction mechanisms, we have developed the highest conductivity solid electrolyte, stabilized bismuth oxide (Dy0.08W0.04Bi0.88O0.36). To overcome its inherent thermodynamic instability in the anode environment, we invented a functionally graded bismuth oxide/ceria bilayered electrolyte. For compatibility with this bilayared electrolyte, we developed high performance bismuth ruthenate–bismuth oxide composite cathodes. Finally, these components were integrated into an anode-supported cell with an anode functional layer, resulting in an exceptionally high power density of ∼2 W/cm2 at moderate temperatures (650 °C) and sufficient power down to 300–400 °C for most applications. Moreover, because SOFCs can operate on conventional fuels, these low temperature SOFCs provide one of the most efficient energy conversion technologies available without relying on a hydrogen infrastructure.