High-Pressure Oxygen Generating Electrolyzer
The oxygen generating assembly (OGA) on the international space station (ISS) provides key life support function by electrolyzing water into breathing oxygen. The current OGA is designed to operate at low oxygen pressures but higher pressures are desirable to support oxygen recharge of the extravehicular mobility unit (EMU). Giner’s high pressure oxygen generating electrolyzer stack is designed to provide oxygen at pressures of up to 3,600 psi without mechanical compression while hydrogen is discharged at close to ambient pressures.
The liquid cathode feed configuration provides the oxygen in a non-saturated state, making downstream processing easier prior to EMU recharge. The unique stack design allows for stable high differential pressure operation with only ppm levels of oxygen contained in the product hydrogen stream. To date, over 10,000 hours of cumulative operation has been demonstrated on two prototype stacks and a 50-cell stack has been built and successfully operated at 2,000 psi.