A reverse electrodialysis device using a precipitation reaction, according to one embodiment of the present invention, comprises a first cell stack alternately forming solid salt chambers and precipitation chambers through cation-exchange membranes and anion-exchange membranes which are alternately provided, and a first water-soluble solid salt and a second water-soluble solid salt which are filled in the solid salt chambers, wherein the first water-soluble solid salt and the second water-soluble solid salt are alternately filled in the solid salt chambers, and can react with each other so as to generate a precipitate in neighboring precipitation chambers when water is supplied.

The present invention relates to an ion-selective composite membrane having a thickness of between 4 μm and 100 μm, comprising at least one inner layer disposed between two outer layers, wherein: —the outer layers are each formed of a first material comprising a network of nanofibres and/or crosslinked microfibres and pores with a diameter of between 10 nm and 10 μm, —the inner layer is formed of a second material comprising nanoparticles functionalized at the surface by charged groups and/or groups which become charged in the presence of water and having pores with a diameter of between 1 and 100 nm.

A flow-through redox galvanic cell and a battery is described, where each flow-through galvanic cell is separated into two parts by a metal foil serving as a bi-electrode in contact with two solutions having different redox potentials. Voltage due to redox processes is formed through the foil, and two traditional electrodes (cathode and anode) in each cell are not necessary anymore. The cells in a battery should be in electric contact with each other via ion-selective membranes. The battery is easy to recharge, and it is smaller, lighter, safer and cheaper than known redox-flow batteries. It may be used as a reserve source of energy in electric grids and households. It also may be used in electric cars, and it is especially attractive for use near the seashore and on sea ships.

The present invention relates to new anion exchange polymers and (blend) membranes made from polymers containing highly fluorinated aromatic groups by means of nucleophilic substitution and processes for their production by means of nucleophilic aromatic substitution and their areas of application in membrane processes, in particular in electrochemical membrane processes such as fuel cells, electrolysis and redox flow batteries.

Disclosed herein a monovalent-ion-selective composite membrane comprising a polymeric cation exchange membrane and a metal-oxide-based layer, wherein said metal-oxide-based layer comprises a metal oxide or an organic-inorganic hybrid polymer, of e.g. Zn, Al, Mg, Si, Cu, W, Ni, or Ti. Also disclosed are the methods for the preparation of the membrane, and also electrodialysis assemblies comprising the membranes.

A method of generating electrical power or hydrogen from thermal energy is disclosed. The method includes separating, by a selectively permeable membrane, a first saline solution from a second saline solution, receiving, by the first saline solution and/or the second saline solution, thermal energy from a heat source, and mixing the first saline solution and the second saline solution in a controlled manner, capturing at least some salinity-gradient energy as electrical power as the salinity difference between the first saline solution and the second saline solution decreases. The method further includes transferring, by a heat pump, thermal energy from the first saline solution to the second saline solution, causing the salinity difference between the first saline solution and the second saline solution to increase.

The present invention concerns a device for producing electrical energy, comprising: a) a first reservoir A for receiving an electrolyte solution having a concentration CA of a solute and comprising an electrode (30A) in contact with the electrolyte solution having concentration CA; b) a second reservoir B for receiving an electrolyte solution having a concentration CB of one and the same solute, CB being lower than CA, and comprising an electrode in contact with the electrolyte solution having concentration CB; c) a membrane separating the two reservoirs, said membrane comprising pores allowing the electrolytes to diffuse from reservoir A to reservoir B through said pore or pores; and d) a device capable of supplying the electrical energy generated by the potential difference existing between the two electrodes, characterized in that the membrane comprises at least one layer formed of a cellulosic material comprising a network of crosslinked cellulose nanofibres and/or microfibres.

An electrical energy generating device includes an electrical energy generating element, a first container, a second container, and a liquid having positive and negative ions. The electrical energy generating element includes a first porous electrode, an eggshell membrane, and a second porous electrode stacked on each other in that order. The first container is located on a side of the first porous electrode away from the eggshell membrane. The second container is located on a side of the second porous electrode away from the eggshell membrane. The liquid is located in at least one of the first container and the second container, and the liquid is configured to penetrate from one of the first container and the second container to another through the electrical energy generating element.

An electrodialysis apparatus comprises a first reservoir wherein salt dissolved in solvent is reduced below a threshold concentration and a second reservoir wherein the salt concentration increases. A first electrode contacts a first solution of a first redox-active electrolyte material, and a second electrode contacts a second solution of a second redox-active electrolyte material. A first type of membrane is disposed between the first and second reservoirs and a second type of membrane is disposed between the first electrode and the first reservoir and between the second electrode and the second reservoir. A color measuring device is coupled to at least one of the solutions, and a control system is configured to modify the value of a property of at least one of the first and second solutions in response to detecting a color value of one of the solutions exceeding a threshold color value.

An electrochemical separation device includes a first electrode, a second electrode, a cell stack including alternating depleting compartments and concentrating compartments disposed between the first electrode and the second electrode, an inlet manifold configured to introduce a fluid to one of the depleting compartments or the concentrating compartments an outlet manifold, and one or more of a fluid flow director disposed within the inlet manifold and having a surface configured to alter a flow path of the fluid introduced into the inlet manifold and direct the fluid into the one of the depleting compartments or the concentrating compartments, and a second fluid flow director disposed within the outlet manifold and having a surface configured to alter a flow path of the fluid introduced into the outlet manifold via one of the depleting compartments or the concentrating compartments.