Desalination device

A water desalination device comprising:

• at least two desalination battery cells, each cell having a first compartment separated by an anion exchange membrane from a second compartment, the anion exchange membrane being a selective anion-only exchange membrane comprising carbon-based functionalized, electronically conductive material including at least one of functional groups including hydroxyl (—OH), carbonyl (=O), and epoxy (—O), the selective ion exchange membrane being structured to trap cations and diffuse anions,
• each of the first and second compartments configured to contain a saline water solution having a concentration of dissolved salts c, and having first and second intercalation host electrodes, respectively, arranged to be in fluid communication with the solution,
• a first voltage source configured to supply electric current to the first and second intercalation host electrodes;
• a second voltage source configured to supply electric current to the anion exchange membrane only;
• and
• a controller programmed to adjust an amount of the electric current being supplied from the voltage source to the at least two cells such that the device produces desalinated water solution having a concentration cz of dissolved salts and a brine solution having a concentration c3 of dissolved salts, wherein c3>c1>c2.

A desalination battery device comprising:

• a plurality of desalination battery cells arranged in a cascade such that a first row of the cells includes n number of cells, the second row includes at least n+1 number of cells, and each subsequent row includes at least one more cell than a preceding cell row, at least one of the cells having
• a selective anion-only exchange membrane with functionalized, electronically conductive material structured to adsorb and desorb cations and electronically repulse anions to enable free movement of anions within the cell's compartments when a voltage of less than 3V is applied to the cell, and
• two intercalation electrodes at least one of which includes expanded graphene sheet material comprising layers having an interlayer distance of about 0.37 to 0.70 nm;
• a voltage source configured to supply electric current to the plurality of desalination battery cells;
• and
• a controller programmed to control an amount of the electric current being supplied to the cells such that the device produces desalinated water solution having a predetermined concentration c2 of dissolved salts and a brine solution having a concentration c3 of dissolved salts, wherein c3>c1>c2.