Abstract: A process for rebalancing the electrolyte system in a regenerative fuel cell using a sulfide/polysulfide reaction in one half of the cell and a bromine/bromide reaction in the other half of the cell comprises passing the electrolyte containing sulfide/polysulfide or bromine/bromide through the +ve chamber of an auxiliary cell and passing an electrolyte containing water and being free from polysulfide or bromine through the ?ve chamber of the auxiliary cell the auxiliary cell operating so as to oxidize sulfide ions to sulfur or bromide ions to bromine in the +ve chamber and to reduce water to hydrogen and hydroxide ions in the ?ve chamber.

Abstract: A carbon based electrode for the electrochemical reduction of sulfur or oxygen, which comprises an electrode core and, in electrical contact therewith, a structure comprising a porous particulate activated carbon bonded with a polymeric binder material, characterised in that the structure is at least 1 mm thick, in that the particulate activated carbon is prepared from a lignocellulosic material and has the following properties: i) a particle size in the range of from 200 to 850 &mgr;m; ii) a pore volume of from 0.45 to 1.0 cm3 per gram; iii) a surface area in the range of from 800 to 1500 m2/g; and in that the binder is used in an amount not exceeding 25% by weight based upon the mixture of activated carbon and binder material.

Abstract: A method for the removal of sulfate ions from an electrolyte of an electrochemical reduction-oxidation system wherein said electrolyte comprises a halogen and in which the sulfate ions an a contaminant or interferant, which method comprises the steps of: (i) increasing the halide concentration in the electrolyte by electrochemical reduction of the halogen, (ii) crystallizing a sulfate salt out of the electrolyte, and (iii) separation of the electrolyte from the crystallized sulfate salt. An electrochemical process for energy storage and/or power delivery comprising the step of removal of sulfate ions from the electrolyte according to the above cited method is also disclosed.

Abstract: A process for the fabrication of an electrochemical cell component which comprises an ion exchange membrane joined to a frame member formed from a dissimilar polymeric material, which process comprises the steps of: i) coating the border of at least one face of an ion exchange membrane with a solution in a solvent which is miscible with water of the polymeric material from which the same frame member is made, or of a polymeric material which is compatible with the polymeric frame material; ii) optionally allowing the said coated membrane to stand and/or drying the said coated membrane; iii) placing the coated face of the ion exchange membrane from step (i) or step (ii) in contact with said frame member; and iv) joining the coated ion-exchange membrane to the said frame member.

Abstract: A method of fabricating an electrochemical or galvanic cell comprising a plurality of electrochemical components, which electrochemical components are joined together in a stack, which method comprises: i) providing a first component formed from a deformable polymeric material with at least one substantially continuous groove comprising a female opening having a width of "w" and a depth of "h"; ii) providing a second component with at least one substantially continuous upstand having a width of >"w" and a height of <"h"; iii) pressing the first and second components together in order to provide an integral seal between the upstand on the second component and the opening in the first component, with the seal between the parts being provided by sealing engagement of the sides of the upstand with the sides of the openings; and iv) joining a plurality of first and second components together to form a stack.