Abstract: A method and system for reducing ion concentration of a solution and converting gas. The system comprising a multi-chamber unitary dialysis cell comprising a gas chamber, a product chamber, and an acid chamber. Ion exchange barriers separate the chambers of the dialysis cell. A first anion exchange barrier is positioned between the product chamber and the acid chamber and a first cation exchange barrier is positioned between the product chamber and the gas chamber. Anions from the solution being treated associate with cations from the acid chamber to form an acid solution in the acid chamber, and cations from the solution being treated associate with anions from the fluid comprising gas to form salt, thereby reducing the ion concentration of the solution being treated and converting at least a portion of the gas into salt.

Abstract: A fuel cell comprises an anode having an inner face and an outer face fluidly communicable with a fuel; a cathode having an inner face ionically communicable with and physically separated from the anode inner face, and having an outer face fluidly communicable with an oxidant; and at least one movable guard movable over at least one of the anode outer face, cathode outer face, anode inner face, and cathode inner face. The guard has a structure sufficient to block at least part of one or more of the anode's communication with the fuel, the cathode's communication with the oxidant, and the ionic communication between the anode and cathode thereby reducing a maximum potential active area of the fuel cell to an effective active area of the fuel cell.

Abstract: A method and system for reducing ion concentration of a solution and converting gas. The system comprising a multi-chamber unitary dialysis cell comprising a gas chamber, a product chamber, and an acid chamber. Ion exchange barriers separate the chambers of the dialysis cell. A first anion exchange barrier is positioned between the product chamber and the acid chamber and a first cation exchange barrier is positioned between the product chamber and the gas chamber. Anions from the solution being treated associate with cations from the acid chamber to form an acid solution in the acid chamber, and cations from the solution being treated associate with anions from the fluid comprising gas to form salt, thereby reducing the ion concentration of the solution being treated and converting at least a portion of the gas into salt.

Abstract: A direct fuel cell comprises a cathode comprising electroactive catalyst material; and an anode assembly comprising an anode having a porous layer and electroactive catalyst material in the porous layer. The electrode characteristics of the anode assembly are selected so that fuel supplied to the anode is reacted within the anode so that cross-over from the anode to the cathode does not have more than a 10% negative effect on voltage or a 25 mV voltage loss when at peak power and steady state conditions. The anode and cathode each have a first major surface facing each other in non-electrical contact and without a microporous separator or ion exchange membrane therebetween.

Abstract: A fuel cell comprises an anode having an inner face and an outer face fluidly communicable with a fuel; a cathode having an inner face ionically communicable with and physically separated from the anode inner face, and having an outer face fluidly communicable with an oxidant; and at least one movable guard movable over at least one of the anode outer face, cathode outer face, anode inner face, and cathode inner face. The guard has a structure sufficient to block at least part of one or more of the anode's communication with the fuel, the cathode's communication with the oxidant, and the ionic communication between the anode and cathode thereby reducing a maximum potential active area of the fuel cell to an effective active area of the fuel cell.

Abstract: A direct fuel cell comprises a cathode comprising electroactive catalyst material; and an anode assembly comprising an anode having a porous layer and electroactive catalyst material in the porous layer. The electrode characteristics of the anode assembly are selected so that fuel supplied to the anode is reacted within the anode so that cross-over from the anode to the cathode does not have more than a 10% negative effect on voltage or a 25 mV voltage loss when at peak power and steady state conditions. The anode and cathode each have a first major surface facing each other in non-electrical contact and without a microporous separator or ion exchange membrane therebetween.