Abstract: An apparatus for removal of ions from water having: a carbon coated first current collector; a second current collector; a spacer in between the first and second current collectors to allow water to flow in between the first and second current collectors; a first charge barrier in between the first carbon coated current collector and the spacer to selectively allow anions or cations to flow through the first charge barrier. The apparatus may have a second charge barrier coated on the carbon coated first current collector and in contact with the first charge barrier to improve contact. A third charge barrier functioning as a membrane may be provided in between the second current collector and the spacer.

Abstract: An apparatus to remove ions including a plurality of capacitive electrode stacks. Each capacitive electrode stack may have: a plurality of first electrodes including a plurality of first current collectors; a plurality of second electrodes including a plurality of second current collectors; and a spacer between the first and second electrodes to allow water to flow in between the electrodes. The second current collectors of a first of the plurality of capacitive electrode stacks may be connected to the first current collectors of a second of the plurality of capacitive electrode stacks.

Abstract: An apparatus to remove ions from water. The apparatus may include a stack having a first electrode including a first current collector, a spacer on top of the first electrode, and a second electrode on top of the spacer. The stack may have a tray to hold and position the stack within a housing of the apparatus and thus may improve the manufacturability of the apparatus.

Abstract: A method to prepare a coated current collector electrode of a flow through capacitor. The method includes preparing a coating paste includes: 10-50 weight % of carbon having a specific surface area of at least 500 m2/g; 0.3-5 weight % of a binder; 10-50 weight % based on the total paste of a first solvent having a first boiling point; and 10-50 weight % based on the total paste of a second solvent having a second boiling point. The method further includes applying the coating paste on a current collector; and allowing the second solvent in the coating paste applied on the current collector to evaporate at a temperature lower than the first boiling point.

Abstract: A method of producing an apparatus to remove ions from water is disclosed, wherein the apparatus includes a first electrode having a first current collector, a second electrode having a second current collector, and a spacer between the first and second electrodes to allow water to flow in between the electrodes. The method includes flushing water through the spacer and subsequently exerting a force on the stack so as to compress the first and second electrodes and the spacer. Exerting a force on the stack may result in a pressure of less than 5 bar, less than 2 bar, or between 1 bar and 0.5 bar, between the electrodes and the spacer.

Abstract: An apparatus and a method to remove ions from water. The apparatus has a housing, an inlet to let water into the housing, an outlet to let water out of the housing, a first and second electrode connected to a power supply configured to create an electrical potential difference between the first and the second electrodes, and a spacer between the first and second electrodes to allow water to flow in between the first and second electrodes. The apparatus includes a velocity adjuster constructed and arranged to adjust a flow velocity of a first portion of the water flowing between the first and second electrodes with respect to a second portion of the water flowing between the first and second electrodes.

Abstract: An apparatus for removal of ions from water having: a carbon coated first current collector; a second current collector; a spacer in between the first and second current collectors to allow water to flow in between the first and second current collectors; a first charge barrier in between the first carbon coated current collector and the spacer to selectively allow anions or cations to flow through the first charge barrier. The apparatus may have a second charge barrier coated on the carbon coated first current collector and in contact with the first charge barrier to improve contact. A third charge barrier functioning as a membrane may be provided in between the second current collector and the spacer.

Abstract: A method of producing an apparatus for removal of ions from water. A stack of the apparatus may be manufactured by: providing a first electrode with a first current collector; providing a spacer on top of the first electrode; and providing a second electrode on top of the spacer. The first electrode may be connected with a first connector to a first power terminal and a pressure may be exerted on the stack so as to move the first and/or second electrodes. The first connector may allow movement of the first electrode with respect to the first power terminal.

Abstract: An apparatus to remove ions, the apparatus including a capacitive electrode stack. The capacitive electrode stack has a first electrode that includes a first current collector, a second electrode, and a spacer between the first and second electrodes to allow water to flow in between the first and second electrodes. The apparatus has a connector to connect the current collector inside the housing with an electrical source outside the housing, and the connector includes a closing off portion to close an opening in the housing and to form a boundary for the water in the housing.

Abstract: An apparatus to remove ions, the apparatus including an inlet to let water in the apparatus; an outlet to let water out of the apparatus; a capacitor; and a spacer to separate a first and a second electrode of the capacitor and to allow water to flow in between the electrodes. The apparatus further including a power converter configured to convert a supply voltage of a power source to a charging voltage to charge the capacitor. The power converter is constructed and arranged to recover energy from the capacitor by converting the voltage on the capacitor to supply voltage of the power source.

Abstract: An apparatus to remove ions, the apparatus having a housing including an inlet to let water in an interior of the housing, an outlet to let water out of the interior of the housing, a first electrode having a current collector, a second electrode, and a spacer to separate the first and second electrodes and to allow water to flow between the first and second electrodes. The apparatus also has a connector to connect the first electrode, or the second electrode, or both first and second electrodes, with an electrical source. The connector may have two connector parts to clamp the current collector in between the connector parts, the connector constructed and arranged to avoid water-metal contact.

Abstract: A method of producing an apparatus to remove ions from water is disclosed, wherein the apparatus includes a first electrode having a first current collector, a second electrode having a second current collector, and a spacer between the first and second electrodes to allow water to flow in between the electrodes. The method includes flushing water through the spacer and subsequently exerting a force on the stack so as to compress the first and second electrodes and the spacer. Exerting a force on the stack may result in a pressure of less than 5 bar, less than 2 bar, or between 1 bar and 0.5 bar, between the electrodes and the spacer.

Abstract: A method of operating a capacitive deionization cell using a regeneration cycle to increase pure flow rate and efficiency of the cell.

Abstract: An apparatus to remove ions from water. The apparatus may include a stack having a first electrode including a first current collector, a spacer on top of the first electrode, and a second electrode on top of the spacer. The stack may have a tray to hold and position the stack within a housing of the apparatus and thus may improve the manufacturability of the apparatus.

Abstract: A method of preparing an anion exchange membrane with anion exchange groups. The method includes polymerizing a first monomer with a functional group selected from the pyridine derivatives with a second monomer selected from the benzene derivatives, such as styrene, to form a copolymer. The copolymer may be crosslinked with a crosslinker. The functional group of the copolymer may be functionalized to an anion exchange group.

Abstract: An apparatus to remove ions, the apparatus including a housing, an inlet to let water into the housing, an outlet to let water out of the housing, a first electrode, a second electrode, a spacer between the first and second electrodes to allow water to flow between the first and second electrodes, and an ion exchange membrane between the first and/or second electrode and the spacer, wherein the membrane has a crosslinked hyperbranched polymer with ion exchange groups.

Abstract: A method of operating a capacitive deionization cell using charge potentials of 1 V or less.

Abstract: An apparatus and a method to remove ions from water are provided. The apparatus has at least three electrodes: at least two master electrodes, each master electrode including a current collector connected or connectable to a power supply configured to create an electrical potential difference between at least two master electrodes and at least one floating electrode located between at least two master electrodes. The apparatus is constructed to provide a potential difference between at least two master electrodes and to allow water containing ions to flow from an inlet to an outlet between at least two adjacent electrodes. The ions in the water are attracted to the master and floating electrodes by the potential difference and the at least one floating electrode has an ion barrier layer.

Abstract: An evaporative recirculation cooling water system, the system having a recirculation loop to recirculate water through the system, a space to cool the water in the recirculation loop by evaporation, and an ion removal apparatus to remove ions. The ion removal apparatus has a flow through capacitor to remove hardness ions while leaving silica ions in the water. The flow through capacitor has an inlet connected to a water inlet and an outlet having a regulator to direct the flow of water to the recirculation loop or to a waste water output.

Abstract: An apparatus to remove ions, the apparatus including a capacitive electrode stack. The capacitive electrode stack has a first electrode that includes a first current collector, a second electrode, and a spacer between the first and second electrodes to allow water to flow in between the first and second electrodes. The apparatus has a connector to connect the current collector inside the housing with an electrical source outside the housing, and the connector includes a closing off portion to close an opening in the housing and to form a boundary for the water in the housing.