Abstract: A redox fuel cell comprising an anode and a cathode separated by an ion selective polymer electrolyte membrane; means for supplying a fuel to the anode region of the cell; means for supplying an oxidant to the cathode region of the cell; means for providing an electrical circuit between respective anodes and cathodes of the cell; a catholyte solution comprising at least one catholyte component, the catholyte solution comprising a redox mediator couple; and a regeneration zone comprising a catholyte channel and a porous member having an active surface, the catholyte channel being arranged to direct a flow of catholyte adjacent to or towards the active surface, the means for supplying an oxidant to the cell being adapted to supply the oxidant to the porous member.

Abstract: A composition comprising a polyoxometalate and an additive tolerant to the properties of the polyoxometalate, wherein the properties of the polyoxometalate are maintained despite the presence of the additive, and wherein the additive is effective to reduce the freezing point and/or elevate the boiling point of the composition. Such a composition may be used in a fuel cell.

Abstract: A redox fuel cell comprising an anode and a cathode separated by an ion selective polymer electrolyte membrane; means for supplying a fuel to the anode region of the cell; means for supplying an oxidant to the cathode region of the cell; means for providing an electrical circuit between the anode and the cathode; a non-volatile catholyte solution flowing fluid communication with the cathode, the catholyte solution comprising a polyoxometallate redox couple being at least partially reduced at the cathode in operation of the cell, and at least partially re-generated by reaction with the oxidant after such reduction at the cathode, wherein the polyoxometallate is represented by the formula: Xa[ZbMcOd] Wherein X is selected from hydrogen, alkali metals, alkaline earth metals, ammonium and combinations of two or more thereof; Z is selected from B, P, S, As, Si, Ge, Ni, Rh, Sn, Al, Cu, I, Br, F, Fe, Co, Cr, Zn, H2, Te, Mn and Se and combinations of two or more thereof; M comprises W and optionally one or more of

Abstract: There is provided a fuel cell cathode electrode, comprising a porous skeletal medium, the surface of which medium is modified or otherwise arranged or constructed to induce enhanced activated behaviour, wherein the enhanced activated behaviour is induced by means of increasing the surface area for a given volume of the electrode and/or by increasing the number and/or availability of reactive sites on the electrode. A fuel cell having such a cathode electrode, a method of manufacturing such a cathode electrode, and use of such a cathode electrode in a fuel cell is also disclosed.

Abstract: An electrolytic cell comprising an anode in an anode region and a cathode in a cathode region, the anode region and the cathode regions separated by an ion selective polymer electrolyte membrane; an anolyte in flowing fluid communication with the anode, the anolyte comprising water and a redox mediator couple which is at least partially oxidised at the anode in operation of the cell and at least partially reduced by reaction with water after such oxidation at the anode.

Abstract: A redox fuel cell comprising an anode and a cathode separated by an ion selective polymer electrolyte membrane; means for supplying a fuel to the anode region of the cell; means for supplying an oxidant to the cathode region of the cell; means for providing an electrical circuit between respective anodes and cathodes of the cell; a catholyte solution comprising at least one catholyte component, the catholyte solution comprising a redox mediator couple; and a regeneration zone comprising a catholyte channel and a porous member having an active surface, the catholyte channel being arranged to direct a flow of catholyte adjacent to or towards the active surface, the means for supplying an oxidant to the cell being adapted to supply the oxidant to the porous member.

Abstract: There is disclosed a device (1) for generating fine bubbles, comprising a substrate (3) having holes (5) therethrough, each hole comprising a gas inlet (7) and a gas outlet (9), wherein the width of the gas outlet is greater than the width of the gas inlet. A method of manufacturing said device and a method of generating fine bubbles.