Novel Porous-Transport-Layers for Fuel Cells and Clean Energy Applications

Porous transport layers or gas-diffusion layers (GDLs) are the key component of polymer electrolyte fuel cells (PEFCs), which are made by weaving carbon fibres into a carbon cloth or by pressing carbon fibres together into a carbon paper and then rendered wet-proof by fully saturating the pores with a hydrophobic emulsion. PEFCs produce electric power by reacting hydrogen with oxygen with water as its only by-product, making them a clean power solution for next-generation vehicles and drones to reduce greenhouse gas emissions. However, GDL's poor durability, as they are prone to liquid-water flooding, and the cost of fuel-cell stacks hinder their widespread adoption in zero-emission vehicles and drones. Further cost reduction for making fuel-cell stack commercially viable requires cost-effective and durable GDLs.

The proposed research programme introduces innovative concepts to the design and development of novel GDLs for PEFCs and related clean energy applications using state-of-the-art additive manufacturing techniques (3D printing), developing experimental protocols for characterising GDLs, and providing a deeper practical understanding of water-droplet growth and detachment from their surfaces. This project aims to combine experimental characterisation and diagnostics with advanced mathematical modelling to analyse water transport through newly designed GDLs and to optimise their properties for better water removal and higher durability than convectional GDLs. The key work will include the following areas: (i) design and fabrication of GDLs with selective wetting properties and surface structures using additive manufacturing techniques; (ii) characterisation of GDL's surface morphology, roughness, adhesion force, and breakthrough pressure and analysis of water-droplet growth and detachment from GDL; (iii) development of a computational model to simulate interfacial interactions between water-droplets and GDL surface; (iv) modification of an existing PEFC model and incorporation of the interfacial model data to optimise GDLs; (v) validation of GDL's real life performances using in-situ fuel cell performance testing.

The novel GDLs will reduce the cost of fuel-cell vehicles and drones by improving the cell durability and performance, and reducing manufacturing time and material waste during the mass production of fuel-cell components. As many of the known fuel cell technologies have been developed in North America, Asia and Germany and acquired in the UK by license agreement, the proposed project will provide a unique opportunity for the UK be the leader in tailored GDLs as well as be the precursor in the development of next-generation fuel cells for vehicle and drone applications.

This project is relevant to two broad areas - the academic community and the commercial sectors interested in fuel cells and related clean energy technologies (such as redox flow-batteries and solar-fuel generators). The proposed 3D printed tailored GDLs are expected to impact established fuel cell and clean energy companies in the UK, for instance, Johnson Matthey Fuel Cells Ltd (Swindon, UK), Intelligent Energy Ltd (Loughborough, UK), Auriga Energy Ltd (Bristol, UK), ITM Power (Sheffield, UK). This research programme will provide links to the EPSRC Centre for Doctoral Training (CDT) in Fuel Cells and their Fuels (University of Birmingham), the SUPERGEN Energy Storage Research Consortium, and the H2FC SUPERGEN. On a broader scale, advancing the development of fuel cell technology will reduce global CO2 emissions, improve air quality, contribute to UK energy security and have an enabling role in the move towards a low carbon economy. This project will improve the commercialisation opportunities for PEFCs for vehicle and drone applications by increasing energy conversion efficiency and reducing material cost significantly due to the improved durability; which would result in the huge reduction of greenhouse gas emissions to benefit the environment. The tools and techniques established through this project in computational modelling, additive manufacturing, characterisation and testing will strengthen the UK's capacity in fuel-cell vehicles and drones development and technology translation.

A successful result for this project could result in IP generation which may be licensed to one of the aforementioned companies or a different company or may allow formation of a spin-out company (and thus including the potential for creation of new jobs). The PI and the support team of this project have excellent links with the fuel cell community in North America and UK, which will form a key outlet for this proposed research in later stages of the project. Successful completion of this project will also create a platform for international collaboration with the US Department of Energy and their national laboratories, including Lawrence Berkeley National Laboratory (Berkeley, California) and National Renewable National Laboratory (Golden, Colorado) as well as with fuel cell companies, including Ballard Power Systems (Vancouver, Canada) and General Motors (Detroit, USA).

There are a range of societal impacts may result from the efficient commercialisation of this research, which would accelerate deployment of fuel-cell vehicles, stationary fuel cell systems, and hydrogen drones due to improved energy densities, energy efficiencies and higher durability. This will decrease CO2 emissions, aiding the UK to achieve its CO2 reduction targets, decrease atmospheric contaminants in urban environments, and decarbonise UK's domestic heat and transport sectors.