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.