LOWCOST-PBI-HTPEMFC · Novel binder-ionomer-free electrodes enable ultra-low Pt loading electrodes for low cost High Temperature proton exchange membrane fuel cells based in phosphoric acid-doped polybenzimidazole membranes
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2018-08-15 → 2020-08-14
- EU contribution
- €212,195
- Participants
- 1
- Scheme
- MSCA-IF-EF-CAR
Lines connect the coordinator with its partners.
Results in brief
Novel binder-ionomer-free electrodes enable ultra-low Pt loading electrodes for low cost High Temperature proton exchange membrane fuel cells based in phosphoric acid-doped polybenzimidazole membranes
This project addresses the issue of the precious metal content of the electrodes of polybenzimidazole-based High Temperature Polymer Electrolyte Membrane Fuel Cells (HT-PEMFCs). It´s well known that the high amount of precious metal (Pt and Pt-alloys) incorporated as catalyst in the electrodes of PEMFCs is one of the main factors limiting the worldwide commercialization of this promising and zero emissions technology. This issue is even more aggravated in the case of HT-PEMFCs whose state-of-the-art Pt loading is about 10 times higher than its homologous Low Temperature (LT-) PEMFCs based in perfluorosulphonic acid membrane (Nafion TM). In spite of being the most widespread kind of PEMFC, LT-PEMFCs has not yet reached the expected penetration in the automobile and green-energy sector due to the lack of an infrastructure for fuel (hydrogen) production and distribution. Nowadays, the most common source of H2 are the already existing fossil fuels as hydrocarbons (e.g.: methane or natural gas). By means of steam reforming of hydrocarbons can be obtained an H2-rich fuel that can be used in PEMFCs. But this fuel contains CO (in the volume percent range) that poisons the catalyst and deteriorates the fuel cell performance. At the operating temperature of LT-PEMFCs (60-80ºC) only 10-20 ppm of CO can be tolerated, so, a purification of the gas is needed to lower the CO content down to the tolerable range. In contrast, the operational temperature of HT-PEMFCs (120-200ºC) allow tolerating CO impurities in a concentration up to 1000 times higher than its LT-PEMFCs counterpart. This high CO tolerance makes possible HT-PEMFCs to be fueled directly from the reformer without purification steps what makes a simpler and more efficient fuel cell system. In spite of the promising prospects of this technology, there is still a major issue to overcome: the high amount of precious metal catalyst (Pt or Pt alloys) incorporated in the electrodes of the HT-PEMFCs. The state-of-the-art Pt loading is currently around 1 mgPtcm-2. In contrast, LT-PEMFCs run at similar efficiency with electrodes loaded to around 0.1 mgPtcm-2. So the goal for the HT-PEMFC technology is to diminish the amount of catalyst in the electrodes without compromising the performance. This ambitious objective has been addressed in this project by a paradigm shift regarding to the traditional composition of the catalytic layer of the electrode.
Data: CORDIS, © European Union
Project objective
In spite of the promising prospects as future green energy conversion device, low temperature-proton exchange membrane fuel cells (LT-PEMFCs) based in perfluorosulfonic acid membrane have achieved a penetration in the energy market rather low, being cost and durability the main barriers to the worldwide commercialization. As an alternative, high temperature- (HT-) PEMFCs based in phosphoric acid-doped polybenzimidazole membranes are gaining much of attention due to the benefits over the LT-PEMFCs (e.g. no need of auxiliary humidification system, much higher CO and sulfur tolerance, very suitable for cogeneration in combined heat and power systems, easier thermal management, etc.). However, the main drawback is the high Pt content of the electrodes that, according to the state-of-the-art, is greater than 0.5 mgPt cm-2 (2-5 times higher than LT-PEMFCs state-of-the-art). This project aims to develop a novel configuration of the HT-PEMFC electrode that enable the achievement of low cost ultra-low Pt loading electrodes (≤ 0.1 mgPt cm-2) with competitive power output and durability. A paradigm shift is proposed in the structure and composiition of the catalytic layer of the HT-PEMFC electrode as no ionomer or binder is incorporated, only the catalyst and the electrolyte (phosphoric acid) are present. The absence of Pt site-blockers, as the binder or the ionomer polymers, significantly enhance the electrochemical surface area at ultra-low Pt loadings enabling a reasonable performace output. Results of this project have a strong potential to be transferred to the electrode production in the emerging industry of HT-PEMFCs. The project involves a number of analytic techniques and specific equipment that ensures the transfer of knowledge and the training to the experienced researcher while the candidate will bring his expertise in LT-PEMFCs as a positive feedback to the HT-PEMFCs research field.
Original text from CORDIS.
Participants
- DANMARKS TEKNISKE UNIVERSITET · Kongens LyngbyCoordinatorDenmark
Links
Data: CORDIS, © European Union