Fuel cells are the key technology to decarbonize the heavy-duty transport, aviation and shipping sectors. High Temperature Proton Exchange Membrane (HT-PEM) fuel cells, among other types, are ideally suited for these sectors because operating at a temperature between 160oC and 180oC means simpler heat management and a far greater tolerance of hydrogen impurities. One of the limiting factors of current commercialization of this technology is the large amount of platinum required to achieve effective Oxygen Reduction Reaction (ORR) at the cathode of HT-PEM fuel cells.
With total precious metal loadings being as high as 1.7 mg/cm2 in legacy PBI based MEAs, the power density required for heavy duty cycles and durability can be achieved. At a nominal point of operation, i.e. 0.58V at 0.6 A/cm2 (corresponding to a power output of ~0.35W/cm2), the amount of Platinum needed in a 100kW fuel cell stack would be around half of a kg, leading to a huge CAPEX and a hazardous reliance of the nobility raw material (80% is produced outside of Europe in, primarily South Africa and Russia).
This project has validated a way to increase performance at HT-PEM cathode side using Ni-W/Pt core-shell nanoparticles (NICKEFFECT project), substantially reducing the total Pt content. This architecture aims to overcome the issue of the expensive Platinum use by replacing the “bulk” of the Platinum particles with an inexpensive Ni-based core, placing Platinum only on the active surface. Thus, the advantages of the Advent PBI system, like the operating temperature of 160oC and the CO tolerance of 100 ppm, are conserved, while a pathway towards an ultra-low loading fuel cell is created. Nickel production is not yet on a large European scale but, compared to platinum, distribution is far less localized, the costs are much lower and, as such, we may create very low-cost fuel cells and supply chains for a future where Europe is not dependent on foreign noble raw materials.
Replacing Platinum in Hydrogen Conversion – A Breakthrough in HT-PEM Fuel Cells
The development and deployment of hydrogen production and use will be the “foundation of any measure” to cut emissions and achieve climate neutrality by 2050. Production plans envisage the large-scale deployment of electrolyzers, however, to make a functioning hydrogen economy work, “users” of the fuel cell must become equally important. Within this, High-Temperature Proton Exchange Membrane (HT-PEM) fuel cells seem to hold unique promises for heavy-duty transport, air and sea. Their operating temperatures of between 160oC and 180oC imply a much easier heat management than at lower temperatures and better impurity tolerance. So, what is holding back their large-scale commercial implementation is a high dependence on platinum for the Oxygen Reduction Reaction (ORR).
Replacing the best catalyst ever for energy production: that’s the challenge
Platinum has served as the ‘gold standard’ for catalysts for decades. It is indispensable because it has demonstrated that it can drive the necessary reactions and at the same time operate in a highly corrosive, acidifying environment. However, as Europe builds the hydrogen fleet on a vast scale, platinum begins to look like a liability rather than an asset. The fact is, we’re not just after a substitute that’s cheaper: we’re looking for something that is every bit as atom efficient, and as long lasting as the very best catalyst ever known. We are not looking for a substitute metal, but for a total re-engineering of the catalyst surface.
The Economic Cost of Noble Metals
Up to now, to fulfil the needs of the fuel cells for industrial cycles have reached total precious metal loading as high as 1.7 mg/cm2. For a 100kW fuel cell stack at nominal working point 0.58V at 0.6 A/cm2, a near 0.5 Kg of platinum per vehicle would be needed; which constitutes a huge CAPEX and hazardous dependency upon noble raw materials from outside Europe (>80% of total loading). To make Europe’s strategic autonomy, this loading must be decreased drastically.
The Breakthrough: electrodeposited Core-Shell electrocatalysts Technology
In this framework the NICKEFFECT project successfully demonstrated a solution to HT-PEM cathodes by employing NI-based core-shell nanoparticles with reduced amount of Pt. This design replaces a solid Pt catalyst with a cheap Ni-based alloy core covered by a thin layer of Pt. The NPs are grown directly on the fuel cell gas diffusion layer without intermediate steps. Such architecture enabled the system to be robust to high temperature operation with a significant reduction on the total Pt content (at least 25 %). Although Ni is not manufactured on a large scale in Europe, its global availability is significantly more homogeneous than Pt and its cost is only a negligible fraction of it.
Manufacturing Scalability: From Lab to Industry
An innovation is only as good as its capability for mass production. The NICKEFFECT project focused on the scalability factor, progressing from lab-scale coupons to 46 cm2 large-area electrodes.
- Precision Deposition: Electrodeposition allows us to place nanoparticles precisely where they need to be on the GDL and maximizes “atom economy” (the electrocatalyst use).
- Scalable electrode manufacturing: The project developed robust, industry-compatible fabrication routes for large-area, free-standing electrodes, demonstrating excellent reproducibility, structural integrity, and electrochemical performance at scale.
- Towards industrial readiness: By combining scalable processing with high-performance electrode architectures, NICKEFFECT demonstrated the potential for cost-effective manufacturing approaches compatible with future commercial fuel cell and electrolyser technologies, achieving an Open Circuit Voltage (OCV) of 986 mV, close to the theoretical limit.
Conclusion: A Secure Hydrogen Future
Switching away from platinum bulk material to nickel-based core structures, this also changes radically the cost basis for the fuel cell industry. This ensures Europe does not swap one dependency on fossil resources for one on limited noble metals, imported from outside Europe, once large-scale hydrogen production is implemented. The NICKEFFECT manufacturing path represents a technically sound, cost-efficient model for an indigenous and sustainable hydrogen economy.