PLANT

Mantra advances fuel cell technology for energy storage

Swiss-roll MRFC could reduce the cost and increase the durability of direct liquid fuel cell systems.


At work at Mantra’s R&D facility in Burnaby, BC. Photo: Mantra

BURNABY, BC — Mantra Energy Alternatives Ltd. is developing a fuel cell that could provide relatively low cost systems with high volume power density.

Mantra, a wholly owned subsidiary of Mantra Venture Group Ltd., a producer of high-value, carbon-negative chemicals and fuels based in Burnaby, BC, says the platinum- and membrane-free mixed-reactant fuel cell (MRFC) architecture called the Swiss-roll MRFC doesn’t require expensive platinum-based electro catalysts. It also eliminates the need for expensive and failure-prone polymer electrolyte membranes (PEM) and heavy, bulky bipolar plates.

“As a result, Swiss-roll MRFC stack could significantly reduce the cost and increase the durability of the direct liquid fuel cell systems, while providing a high volumetric power density,” the company says in a release.

It explains that in a conventional fuel cell, the fuel and oxidant flow in separate streams and are kept apart by an ion-conducting membrane that divides the cell into discreet anode and cathode chambers. The single-cells are in series using bipolar flow-field plates that provide most of the stack weight and volume.

In a mixed-reactant fuel cell, a mixture of fuel and oxidant flows through the cell as a single stream, which allows for a variety of conventional and unconventional cell stack designs.

The company says simplification of MRFC systems is possible because they can operate without the gastight structures within the stack that are required for sealing, manifolding, and separating reactant delivery in conventional fuel cells.

The technology has been developed with the Department of Chemical and Biological Engineering at the University of British Columbia (UBC) in the Fuel Cells and Applied Electrochemistry Laboratory, with support from the Clean Energy Research Center and the Natural Science and Engineering Research Council of Canada (NSERC) through Discovery and Discovery Accelerator programs.

Mantra says development of the architecture at UBC has resulted in significant engineering improvements and a potential cost reduction for fuel cells with direct liquid/air systems such as formate/formic acid, borohydride and hydrazine. This may open new avenues for commercialization for various applications such as energy storage units and emergency back-up power systems.

Amin Aziznia, Mantra’s senior electrochemical engineer, says performance matches the highest power densities of conventional systems with platinum-based catalysts and polymer membranes. “Most importantly, the elimination of polymer membranes may significantly improve the performance and stability of many fuel cell chemistries such as direct hydrazine/air fuel cells.”

He says Mantra is currently investigating the adoption of MRFC for formic acid, formate, and direct hydrazine/air systems in its R&D facility in Burnaby.

“A low cost mixed-reactant fuel cell system is an important step toward Mantra’s successful business case for CO2 electro reduction to fuels,” says Patrick Dodd Mantra’s CTO. “We are currently exploring the integration of Mantra’s electrochemical reduction (ERC) technology for CO2 reduction to formic acid/formate with the MRFC. The implication for energy storage applications is currently being explored within our R&D team and with our international collaborators.”

ERC is a carbon capture and utilization technology that converts the pollutant CO2 into useful products including formic acid and formate salts. By using clean electricity, the process would potentially help an industrial plant to reduce emissions while generating a saleable product.