What are the main functions of the air turbo compressor within the cathode module?

The air turbo compressor is the core part of the cathode module, comprising a humidifier, power electronics and a back pressure regulator. The cathode module is responsible for supplying oxygen into the fuel cell stack. The demand-oriented, supplementary provision of oxygen is important to avoid the “oxygen starvation phenomenon” that damages the polymeric membranes and reduces the fuel cell lifetime. The use of an air compression device to this end, rather than a tank with pure oxygen, is preferred for safety, packaging, and refuelling reasons. The air has to be supplied and maintained at the right pressure but, the cathode module has also to ensure proper humidity conditions and manage the nitrogen contained in the air, which can hamper the movement of oxygen to the cathode reaction sites.

What are the development goals for the cathode module?

The overall goal for the INN-BALANCE developments in the cathode module is to increase its efficiency and to ensure a perfect interplay with the other components of the fuel cell stack. INN-BALANCE will therefore focus on the development and testing of a compact and high-efficient air turbo compressor with gas bearings. The target is a power range of 10-12 kW at highest efficiency and power density. This new compressor offers 100% oil-free and lubricant-free compression of air. Thanks to the oil-free operation, the polymeric membranes won’t be stressed with contaminants.

Beside the air turbo compressor developments, INN-BALANCE will also work on the associated power electronics which will be integrated with a humidifier and a back pressure regulator.