This may also be done in space, as in the Russian Mir space station, but at the expense high electrical power consumption and stringent safety measures, due to the corrosive nature of the electrolyte fluid. The innovation in the present electrolyser is the fixation of the electrolyte in a porous matrix, which eliminates the need for an electrolyte pump and allows safer operation under micro-gravity conditions. There is no need to separate gas from water, a particular problem in micro-gravity. A schematic of a single FAE cell is shown in Figure 1. Schematic of a single cell using a fixed alkaline electrolyte for air revitalisation.
Water is pumped through the water compartment and is used simultaneously as feed and coolant.
The hydrophobic porous membrane only admits water in the vapour phase and prevents direct contact between the coolant and the electrolyte. The difference in partial pressure is the main driving force. The electrolyte is sandwiched between the electrodes and is held inside the matrix and electrode system by capillary forces. The electrolyser stack consists of identical cells connected electrically in series. The margins in the design allow of the various parts to be manufactured on a commercial basis, to keep the stack production cost down.