Technology
What is it?
A compressor in which hydrogen is supplied at the anode and then driven through a polymer exchange membrane to the cathode via the application of an electric current, where it is collected in a compressed form on the other side.
Why is it important?
Electrochemical compression has the potential to displace mechanical compression by operating at higher efficiencies (70-80 per cent), with a smaller footprint and the benefit of no moving parts. This can result in lower maintenance costs, reduce stack costs, and noiseless operation.
Characteristics
- Gravimetric hydrogen density: N/A
- Storage conditions: High pressure (up to 1000 bar)
- Compression efficiency: 70-80%
Benefits
- Hydrogen product easily extracted
- Solid state membrane
- No moving parts – lower maintenance costs and noiseless operation
- Higher efficiencies than traditional mechanical compression
- Output compressed hydrogen pressures of approximately 1000 bar have so far been reached with this technology.
- Can operate from very low pressure
Limitations
- High capital cost
- Lifetime and sensitivity to impurities such as reactive gas species
- Reverse permeability leads to movement of hydrogen gas back into non-pressurised side of system
RD&D priorities
- Improve compressor reliability
- Fabricate new membranes
- Reduce electro-osmotic drag (EOD)
- Maintain stack seals at higher operating pressures
- Reduce stack costs
Known active organisations
- CSIRO