Flow-through electrode capacitive deionization cell

Abstract

Disclosed here is a capacitive deionization device for removing ions from a target solution. The capacitive deionization device includes a first porous electrode, a second porous electrode, a first header plate, a second header plate, and a sealant. The second porous electrode is disposed below and spaced from the first porous electrode. The first header plate is disposed on the first porous electrode. The first header plate defines an input flow channel that is in fluidic communication with the first porous electrode. The second header plate is disposed below the second porous electrode. The second header plate defines an output flow channel that is in fluidic communication with the second porous electrode. The sealant is disposed between the first header plate and the second header plate and surrounds the first porous electrode and the second porous electrode.

1 . A capacitive deionization device for removing ions from a target solution, comprising:
 a first porous electrode;   a second porous electrode below and spaced from the first porous electrode;   a first header plate disposed on the first porous electrode, the first header plate defining an input flow channel that is in fluidic communication with the first porous electrode;   a second header plate disposed below the second porous electrode, the second header plate defining an output flow channel that is in fluidic communication with the second porous electrode; and   a sealant disposed between the first header plate and the second header plate and surrounding the first porous electrode and the second porous electrode.   
     
     
         2 . The capacitive deionization device of  claim 1 , further comprising:
 a non-conductive separator disposed between the first porous electrode and the second porous electrode, the non-conductive separator being permeable to the target solution, the sealant surrounding the non-conductive separator.   
     
     
         3 . The capacitive deionization device of  claim 1 , further comprising:
 a first current collector having a first portion and a second portion, the first portion of the first current collector disposed between the first porous electrode and the first header plate and electrically connecting the first porous electrode, and the second portion of the first current collector exposed from the sealant; and   a second current collector having a first portion and a second portion, the first portion of the second current collector disposed between the second porous electrode and the second header plate and electrically connecting the second porous electrode, and the second portion of the second current collector exposed from the sealant.   
     
     
         4 . The capacitive deionization device of  claim 3 , further comprising:
 an electric circuit electrically connecting the second portion of the first current collector and the second portion of the second current collector, during operation the electric circuit producing an electric field across the first porous electrode and the second porous electrode.   
     
     
         5 . The capacitive deionization device of  claim 1 , wherein at least one of:
 the first porous electrode has micrometer-scale pores permeable to the target solution, and the first porous electrode has nanometer-scale pores to which ions of the target solution having a first charge state adsorb in response to an electric field across the first porous electrode and the second porous electrode; or   the second porous electrode has micrometer-scale pores permeable to the target solution, and the second porous electrode has nanometer-scale pores to which ions of the target solution having a second charge state adsorb in response to an electric field across the first porous electrode and the second porous electrode.   
     
     
         6 . (canceled) 
     
     
         7 . The capacitive deionization device of  claim 1 , wherein the sealant is an ultraviolet (UV)-curable epoxy that includes a UV photo-acid generator. 
     
     
         8 . The capacitive deionization device of  claim 1 , further comprising:
 an input flow line attached to the first header plate, the input flow line in fluidic communication with the input flow channel of the first header plate; and   an output flow line attached to the second header plate, the output flow line in fluidic communication with the output flow channel of the second header plate.   
     
     
         9 . The capacitive deionization device of  claim 1 , wherein at least one of:
 the first header plate having an etched surface facing the first porous electrode and an external surface opposite to the etched surface, the first header plate defining the input flow channel adjacent to the external surface, the first header plate defining a plurality of micro-channels distributed on the etched surface adjacent to the first porous electrode, wherein the input flow channel is in fluidic communication with the first porous electrode through the micro-channels distributed on the etched surface; or   the second header plate having an etched surface facing the second porous electrode and an external surface opposite to the etched surface, the second header plate defining the output flow channel adjacent to the external surface, the second header plate defining a plurality of micro-channels distributed on the etched surface adjacent to the second porous electrode, wherein the output flow channel is in fluidic communication with the second porous electrode through the micro-channels distributed on the etched surface.   
     
     
         10 . (canceled) 
     
     
         11 . (canceled) 
     
     
         12 . The capacitive deionization device of  claim 1 , further comprising:
 a reference wire having a first portion and a second portion, the first portion of the reference wire disposed between the first porous electrode and the second porous electrode, the second portion of the reference wire exposed from the sealant.   
     
     
         13 . A capacitive deionization cell for removing ions from a target solution, comprising:
 a first porous electrode;   a second porous electrode below and spaced from the first porous electrode;   a first header plate disposed on the first porous electrode, the first header plate having a first surface facing the first porous electrode and a second surface opposite to the first surface, the first header plate defining a plurality of micro-channels distributed on the first surface adjacent to the first porous electrode, wherein the micro-channels are in fluidic communication with the first porous electrode; and   a second header plate disposed below the second porous electrode, the second header plate having a first surface facing the second porous electrode and a second surface opposite to the first surface, the second header plate defining a plurality of micro-channels distributed on the first surface adjacent to the second porous electrode, wherein the micro-channels are in fluidic communication with the second porous electrode.   
     
     
         14 . The capacitive deionization cell of  claim 13 , further comprising:
 an epoxy sealant disposed between the first header plate and the second header plate and surrounding the first porous electrode and the second porous electrode.   
     
     
         15 . The capacitive deionization cell of  claim 13 , wherein the first header plate further defining an input flow channel adjacent to the second surface of the first header plate, and the input flow channel is in fluidic communication with the first porous electrode through the micro-channels of the first header plate. 
     
     
         16 . (canceled) 
     
     
         17 . A method for fabricating a capacitive deionization cell for removing ions from a target solution, comprising:
 placing a first electrode stack on a bottom header plate, the first electrode stack including a first porous electrode, a second porous electrode and a separator disposed between the first porous electrode and the second porous electrode;   placing a top header plate on the first electrode stack;   applying a mechanical pressure between the top header plate and the bottom header plate; and   disposing a UV-curable sealant between the first header plate and the second header plate and surrounding the first electrode stack.   
     
     
         18 . The method of  claim 17 , further comprising:
 applying a first UV light to cure the UV-curable sealant;   removing the mechanical pressure and flipping an assembly including the top header plate, the bottom header plate, the first electrode stack and the UV-curable sealant; and   further applying a second UV light to cure the UV-curable sealant.   
     
     
         19 . The method of  claim 17 , further comprising:
 placing a first current collector having a first portion and a second portion, the first portion of the first current collector disposed between the first porous electrode and the top header plate and electrically connecting the first porous electrode, and the second portion of the first current collector exposed from the top header plate; and   placing a second current collector having a first portion and a second portion, the first portion of the second current collector disposed between the second porous electrode and the bottom header plate and electrically connecting the second porous electrode, and the second portion of the second current collector exposed from the bottom header plate.   
     
     
         20 . The method of  claim 17 , wherein the disposing a sealant comprises:
 the UV-curable sealant between the top header plate and the bottom header plate using a first syringe having a precision applicator tip; and   removing air bubbles in the UV-curable sealant using a second syringe with a thin needle.   
     
     
         21 . The method of  claim 17 , further comprising:
 etching a first surface of the top header plate to form an etched pattern including a plurality of pillars distributed on the first surface, the pillars defining a plurality of micro-channels on the first surface; and   forming an input flow channel on a second surface of the top header plate opposite to the first surface, wherein the input flow channel on the second surface is in fluidic communication with the micro-channels on the first surface.   
     
     
         22 . The method of  claim 17 , further comprising:
 etching a first surface of the bottom header plate to form an etched pattern including a plurality of pillars distributed on the first surface, the pillars defining a plurality of micro-channels on the first surface; and   forming an output flow channel on a second surface of the bottom header plate opposite to the first surface, wherein the output flow channel on the second surface is in fluidic communication with the micro-channels on the first surface.   
     
     
         23 . The method of  claim 17 , wherein the top header plate, the bottom header plate and the UV-curable sealant form a sealed space accommodating the first electrode stack, and the sealed space is in fluidic communication with an external environment through flow channels of the top header plate and the bottom header plate. 
     
     
         24 . (canceled) 
     
     
         25 . The method of  claim 17 , further comprising:
 pre-curing the first porous electrode or the second porous electrode by stirring a solution of an aerogel material at a predetermined temperature for a predetermined time period; and   
       pouring the solution into a mold.