Fuel_Cell

The key role of the air supply for Low Temperature Polymer Electroylte Membrane Fuel Cells (LT-PEM)

Why LT-PEM fuel cells require an air supply?
Fuel cells need oxygen as a reactant at the cathode for the electrochemical reaction with hydrogen.
The air supply ensures adequate reaction rates, prevents oxygen starvation, and helps maintain stable performance.
Airflow supports thermal and humidity control and removes product water to avoid flooding of the cathode.
Why fuel cells operate more efficiently at higher pressure?
Higher pressure increases the oxygen partial pressure, improving reaction kinetics and reducing cathode overpotentials.
Pressurization leads to a slight increase in cell voltage (Nernst effect) and better performance at high current densities.
Improved pressure conditions enhance mass transport, ensuring more stable operation.
Why an expander (turbine) makes sense?
An expander allows energy recovery from the high‑pressure exhaust air, reducing the net power demand of the compressor.
It increases the overall system efficiency and enables better pressure and thermal management downstream.

Electric Turbocharger Topology

Our Core Concept

The new air‑charging system combines an electrically driven radial compressor with a recuperation turbine, enabling up to 40% energy recovery. Its key features include a merged compressor‑turbine wheel, a cost‑optimized hybrid bearing system, direct gas cooling of the stator, and a slotless toroidal winding motor. This integrated design reduces component count, weight and cost. The production optimized rotor structure allows for easy repair and maintenance.
The electric power output of the machine ranges between 25...150 kW allowing the efficient air supply of PEM-fuel cells ranging between 150 kW up to >1 MW per air supply unit.

What We Offer

HDTI provides comprehensive support along the entire development chain of fuel‑cell air‑supply systems—from early concept studies to full system maturity and performance optimisation. With deep expertise in turbomachinery, electric drives, and fuel‑cell BoP integration, we help you achieve maximum efficiency, robustness, and cost‑effective scalability.

System Optimisation and BoP Matching

Achieving the best performance of a fuel‑cell system requires precise alignment between the air‑supply unit and the overall Balance of Plant. We analyse operating conditions, load cycles, and system interfaces to ensure optimal pressure levels, efficient humidification, stable dynamics, and seamless integration from day one.

Cost Optimisation

Whether developing a new air‑supply concept or improving an existing one, we apply Design‑to‑Cost and Design‑to‑Manufacturing principles to reduce complexity, part count, material usage, and production effort. Our approach balances technical performance with economic viability to support competitive large‑scale manufacturing.

Testing and Validation Support

We provide expert guidance throughout the testing and validation process. We support you in defining test strategies, selecting suitable test facilities, interpreting measurement data, and identifying optimisation opportunities. Our engineering expertise ensures that your fuel‑cell air‑supply system achieves reliable, verifiable performance and smooth integration into the overall BoP.

HDTI Focus

We act as a development leader offering engineering services for the design and integration of Fuel‑Cell Balance‑of‑Plant (BoP) components, with a strong emphasis on advanced air‑supply systems. Building on our experience as developer and system partner for electrically driven, highly efficient turbomachinery in fuel‑cell applications, we focus on optimising performance while minimising system complexity and cost. With our growing involvement across concept development, system integration, and Design‑to‑Cost/Design‑to‑Manufacturing activities, we are steadily moving toward becoming a key supplier for next‑generation fuel‑cell air‑supply solutions. Contact us for more info.