Back to Materials and Compounds list

Low Thermal Expansion Cathode Materials for Solid Oxide Fuel Cells

Project ID: 1815-AP
Available for licensing

Background

This invention is a new class of cathode materials for use in intermediate temperature (500 to 800°C) solid oxide fuel cells. The new cathode [RBaCoMO] overcomes phase instability at elevated temperatures that are known problems of current materials [RBaCoO]. The material offers high catalytic activity for the oxygen reduction reaction in solid oxide fuel cells and maintains a low thermal expansion coefficient compatible with standard electrolytes used. Current solid oxide fuel cells have failure problems where the cathode and electrolytes expand thermally at different rates; this invention is a potential solution to that problem

Solid Oxide Fuel Cells (SOFC) can utilize currently available hydrocarbon fuels such as gasoline, diesel, or natural gas and convert them into electricity at efficiencies much greater than current generator technology (60% vs. 30%). Areas of interest include auxiliary generators for automobiles and standalone power generation units.

Invention Description

Cathodes in solid oxide fuel cells (SOFCs) require both high electronic and oxide-ion conductivities along with good structural and chemical stabilities under the operating conditions of high temperatures. Oxides containing cobalt have shown promise, due to their high oxide-ion and electrical conductivity at high temperatures. However, the high thermal expansion coefficients of cobalt-based oxides has impeded their adoption for practical applications of SOFCs.

Dr. Manthiram's group presents a non-perovskite, hexagonal structure as a potential cathode that can be operated at intermediate temperatures (500 to 800°C) and addresses concerns associated with delamination due to differing thermal expansion rates.

Benefits

High catalytic activity
Improved thermal and mechanical compatibility with electrolytes for SOFC

Features

New class of cathode materials that provide high catalytic performance and matched thermal expansion coefficients to standard electrolytes.

Market Potential/Applications

Commercial markets are still early stage and include portable power systems, micro CHP systems, primary large MW generators, and auxiliary power units for vehicles.

Some of the RBaCoMO cathodes described have been pursued as oxygen-storage materials since they absorb/desorb a large amount of oxygen into/from the lattice at low temperatures of 200 to 400°C.

Development Stage

Lab/bench prototype

IP Status

One U.S. patent application filed

UT Researcher

Arumugam Manthiram, Ph.D., Mechanical Engineering, The University of Texas at Austin
Junghyun Kim, Mechanical Engineering, The University of Texas at Austin

OTC Contact Information

Max Green, Licensing Associate
mgreen@otc.utexas.edu
512-471-9054