Fuel cells and method of operation

A liquid electrolyte fuel cell with means (202) to define an electrolyte chamber (208), and comprising two electrodes (10): an anode (10a) on one side of the electrolyte chamber (208) and a cathode (10b) on the other side. The anode (10a) comprises a sheet (11) of metal through which are defined a multiplicity of through-holes (14), and a gas-permeable layer (16) comprising fibrous and/or particulate electrically-conductive material which is bonded to and in electrical contact with the sheet (11) of metal, and is hydrophobic, and a second fluid-permeable layer (18) comprising fibrous and/or particulate electrically-conductive material and catalytic material, which is bonded to the outer surface of the gas-permeable layer (16), and is less hydrophobic than the first gas-permeable layer (16). The fuel cell (200) also comprises means (26, 50, 44) to adjust the pressure difference between electrolyte (20) within the electrolyte chamber (208) and a gas exposed to the surface of the anode (10a) remote from the elec