Multiscale in-situ characterisation of degradation and reactivity in solid oxide fuel cells

As alternative and low carbon energy technologies are of increasing international importance there is considerable debate as to the most appropriate technology solutions for power generation. For a distrubted generation scenario with power output in the range of kW to MW the solid oxide fuel cell (SOFC) is a leading contender, with development undertaken by many international companies. One of the areas of concern with new technologies is the lifetime of the device and as SOFCs operate at elevated temperatures any degradation of components may be accelerated. Due to the complexity of these devices there has been limited scope to analyse the operation of the SOFC in-situ, and from this determine mechanistic information on degradation processes. It is the aim of this proposal to tackle this challenge.Degradation and reactivity of solid oxide fuel cells may be characterised by processes occuring on a variety of length scales, from chemical reactivity and diffusion processes on the atomic scale through surface chemsitry, stress in functional layers and thermal management over mm and cm. Each of the processes contributes to the overall cell degradation, but may evolve differently depending on the functional component concerned - hence anode and cathode processes will be significantly different. As these are complex devices characterising these processes and the origin of them is challenging and currently results from post-mortem analysis. Whilst this is one route to understanding the failure of devices, an in-situ characterisation under operating conditions will provide detailed direct understanding. Our approach is to develop a combination of complimentary techniques that will allow detailed study of device operation using diffraction, spectroscopy, ion scattering, modelling and emissivity measurements. We will tackle known degradation issues in fuel cells including carbonate and Cr poisoning of cathodes, carbon formation on anodes and electrode delamination and will interact strongly with the UK Supergen Fuel Cells programme. As a result of this programme we will be able to inform industrial partners of mitigation strategies to minimise device degradation and use this information in development of new materials.

In this project our aim is to develop robust in-situ methods for the characterisation and testing of intermediate temperature solid oxide fuel cells with the overall objective of understanding degradation mechanisms. As discussed in the proposal degradation of fuel cell components is an issue of immense significance to commercial developers of fuel cells and hence the advances resulting from this project are likely to impact upon fuel cell development and commercialisation worldwide. Of course with the current requirement to produce energy with low carbon emissions and environmental impact, any advances in understanding of processes that will ultimately accelerate deployment of low carbon energy production will be welcomed. The international interest in this work is highlighted by the support from groups around Europe, the US and also from fuel cell developers. We also note that this crucial work supports the UK national fuel cells programme (Supergen -www.supergenfuelcells.co.uk) in which all of the investigators are participants, and addresses an aspect which is not part of the research programme. Supergen also includes a number of fuel cell companies thus ensuring that the project team have excellent opportunities to maximise the impact of this research. To ensure that the project is successful the project team will meet regularly (at least every 6 months) and will be integrated within the national fuel cells programme, ensuring significant input from the commercial sector.It is our view that the work proposed in this proposal could have significant commercial impact and we will ensure that the necessary intellectual property (IP) is protected by patents, filed through the appropriate technology transfer office of the academic partner institutions. At Imperial College this will be Imperial Innovations who have considerable experience across many technology sectors including in fuel cell technology. St Andrews, UCL and Newcastle have analogous bodies. In cases where the research activities are collaborations across two or more institutions agreements regarding exploitation of any IP generated will be produced prior to the start of the project. Within the project team there are several investigators with a track record of development and exploitation of IP (Profs. Brandon, Kilner & Irvine) and jointly they will be responsible for ensuring that an appropriate IP strategy is followed. Each of these investigators have founded and developed a fuel cell company, with Brandon and Kilner forming Ceres Power, now a ~£60M Imperial spin out company. Once IP is protected we will engage in discussions with potential industry partners under appropriate non-disclosure agreements ensuring that all IP is appropriately protected. We will endeavour to ensure that the project team (Imperial, UCL, Newcastle and St Andrews) will be in a position to exploit the research results and innovations through the respective technology transfer offices and partnership(s) with companies and/or their supply chain. After any patent filing, the non-confidential outputs from the project will be widely disseminated via peer reviewed publication, presentations at major international conferences such as Solid State Ionics, Grove Fuel Cell Symposium, Materials Research Society Symposia, Electrochemical Society Meetings (e.g. SOFC XII) and the UK Fuel Cell and Hydrogen network of which Imperial is an active participant.