FUEL CELL SYSTEM

Abstract

Electrochemical reaction fuel cell system, comprising: a cathode (8), an anode (1), one at least of the anode and of the cathode comprising at least one metal, one metal hydroxide or one metal oxide in the molten state, a solid electrolyte (7), placed between the cathode and the anode, at least one regenerator (4) for regenerating, starting from one at least of the oxidation-reduction reaction products which is recovered at at least one of the anode and of the cathode, by a reaction, at least one of the products constituting at least one of the anode or of the cathode or the fuel or oxidizer consumed at at least one of the anode or of the cathode, one of the regeneration products being reintroduced into the system as electrode made of liquid metal or liquid metal oxide or in the form of fuel or oxidizer, one of the reactions making possible said regeneration or making possible the regeneration of one of the reactants of the oxidation-reduction reaction being endothermic.

Claims

1. An electrochemical reaction fuel cell system, comprising: a cathode, an anode, one at least of the anode and of the cathode comprising at least one metal, one metal hydroxide or one metal oxide in the molten state, a solid electrolyte, placed between the cathode and the anode, at least one regenerator for regenerating, starting from one at least of the oxidation-reduction reaction products which is recovered at at least one of the anode and of the cathode, by a reaction, at least one of the products constituting at least one of the anode or of the cathode or the fuel or oxidizer consumed at at least one of the anode or of the cathode, one of the regeneration products being reintroduced into the system as electrode made of liquid metal or liquid metal oxide or in the form of fuel or oxidizer, one of the reactions making possible said regeneration or making possible the regeneration of one of the reactants of the oxidation-reduction reaction being endothermic.

2. The cell system as claimed in claim 1, the anode comprising a metal in the molten state.

3. The cell system as claimed in claim 1, the cathode comprising a metal oxide in the molten state.

4. The fuel cell system as claimed in claim 3, the molten metal being chosen from the following list: zinc, lithium, magnesium, aluminum, lead, sodium, cesium, rubidium, copper and tin.

5. The fuel cell system as claimed in claim 1, being configured to produce or consume, at the anode or at the cathode, a metal oxide or a metal hydroxide chosen from the following list: zinc oxide (ZnO), lithium oxide (Li.sub.2O), magnesium oxide (MgO), alumina (Al.sub.2O.sub.3), lead oxide (PbO), lead dioxide (PbO.sub.2), sodium oxide (Na.sub.2O), cesium oxide (Cs.sub.2O), rubidium oxide (Rb.sub.2O), copper (II) oxide (CuO), copper (I) oxide (Cu.sub.2O), copper (III) oxide (Cu.sub.2O.sub.3), manganese dioxide (MnO.sub.2), sodium hydroxide (NaOH), manganese hydroxide (MnOOH) and zinc hydroxide (Zn (OH).sub.2).

6. The cell system as claimed in claim 1, comprising a solid electrolyte chosen from: (i) an O.sup.2ion exchange membrane, or (ii) a solid acid, or (iii) an anion exchange membrane, or (iv) a metal ion exchange membrane.

7. The cell system as claimed in claim 6, comprising a separating membrane between the anode and the electrolyte, the separating membrane being an O.sup.2ion exchanger.

8. The system as claimed in claim 7, the separating membrane comprising ceria.

9. The fuel cell system as claimed in claim 7, comprising an electrolyte in the form of a solid oxide.

10. The fuel cell system as claimed in claim 7, being configured to operate at temperatures of 280 C. and 1100 C.

11. The fuel cell system as claimed in claim 9, the solid oxide being chosen from the following list: yttria-stabilized zirconia, referred to as YSZ, scandia-stabilized zirconia, referred to as ScSZ, ceria-salt ceramic composites, referred to as CSCs, erbia-cation-stabilized bismuth, referred to as ERB, gadolinium-doped ceria, referred to as GDC, samaria-doped ceria, referred to as SDC, ceria/bismuth-oxide bilayered electrolyte, referred to as GDC-ESB, formed of a layer of ceria-doped gadolinium and of a layer of erbia-stabilized bismuth oxide, strontium iron oxide SrFeO.sub.2, and their mixtures.

12. The fuel cell system as claimed in claim 1, the O.sup.2ions originating from the separation of molecular oxygen by supplying electrons to the electrode of the cell which absorbs molecular oxygen.

13. The fuel cell system as claimed in claim 1, the metal, the metal hydroxide or the metal oxide consumed at the anode and/or at the cathode originating from at least one reserve.

14. The cell system as claimed in claim 13, one of said reserves being in solid form.

15. The cell system as claimed in claim 1, the or one of the products of the chemical reaction at at least one of the electrodes being separated from the reacting product.

16. The cell system as claimed in claim 15, the separation being carried out by static or nonstatic settling or by centrifugation.

17. The cell system as claimed in claim 1, one of the reactions making possible the regeneration of one of the reactants of the oxidation-reduction reaction being endothermic.

18. The system as claimed in claim 1, all or a portion of the electricity of the electrolysis being provided by the cell.

19. The cell system as claimed in claim 1, wherein said cell system is configured to produce electricity for a vehicle, a dwelling, an industry or a community, and/or for producing electricity to feed or cofeed energy to a device for fusion or for production of neutrons by accelerated ions.

20. The cell system as claimed in claim 19, wherein the heat which is released from the fuel cell is recycled for one or more of the abovementioned reactions but also for, optionally, the oxidation of the manganite.

21. The cell system as claimed in claim 14, one of said reserves being in the form of beads, said beads being melted in order to be introduced in the liquid state at said electrode.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0173] FIG. 1 diagrammatically and partially represents an example of a system according to the invention.

[0174] FIG. 2 diagrammatically and partially represents another example of a system according to the invention.

[0175] FIG. 3 diagrammatically and partially represents another example of a system according to the invention.

DETAILED DESCRIPTION

[0176] There has been illustrated, in FIG. 1, an example of a cell system 11 according to the invention.

[0177] The cell system comprises a battery having electrodes 1 and 8 connected to respective electrical terminals 9 and 10. The electrodes 1 and 8 have the form of compartments.

[0178] The electrodes 1 and 8 are separated by a solid electrolyte 7.

[0179] The electrode 1 consists of a metal or a metal oxide in the liquid state and is recycled in a regenerator 4 where it is regenerated by the supply of heat 3 and then reinjected into the electrode 1 compartment of the cell.

[0180] The electrode 8 or else the fuel supplied to the electrode 8 is ionized by the electrons supplied or withdrawn by the terminal 10 of the cell 11. In addition, the ions pass through the solid electrolyte 7 to cause the liquid electrode 1 to react in combination with the electrons withdrawn or supplied by the terminal 9.

[0181] The cell 11, the electrode 1 of which comprises a metal or a metal oxide in the liquid state, is recycled in the chemical reactor(s) 4 by the supply of heat 3, then reinjected via the pipe 5 into the container of the liquid electrode 1.

[0182] A portion of the regeneration product, for example the metal or the oxygen corresponding to the ions which have passed through the electrolyte 7, can be reintroduced into the compartment of the electrode 8 via a pipe 6.

[0183] In one example, the anode is formed of molten zinc, which circulates in a circuit which ensures, on the one hand, the supply of metal as it is consumed and, on the other hand, the extraction of the oxide.

[0184] The cell can also make possible the transformation of the oxide into metal, continuously, or, in an alternative form, this transformation is carried out noncontinuously.

[0185] The electrolyte is a solid oxide, for example lanthanum strontium cobalt ferrite, advantageously separated from the molten metal by a layer of ceria, this electrolyte allowing the passage of the O.sup.2ions which oxidize the metal, said O.sup.2ions originating from the separation of molecular oxygen by supply of electrons to the cathode of the cell. This cathode consists, for example, of lanthanum strontium manganite, fed with oxygen originating from, for example, the ambient air or the oxygen-enriched air of a zeolite concentrator, or from the regeneration of the metal oxide to give metal.

[0186] The reaction at the anode is:

M+O.sup.->MO+e.sup.

and the reaction at the cathode is:

O.sub.2+2 e.sup.->O.sup.2

where M is the metal, for example zinc Zn.

[0187] The regenerator separates the zinc from the oxide formed. This regenerator can comprise a centrifuge for extracting the zinc oxide from the molten zinc, which circulates to the anode.

[0188] The oxide can be stored pending its reduction to metal. The zinc freed from the oxide can be returned to the anode.

[0189] An alternative form, where the two electrodes 1 and 8 are regenerated by different chemical reactions, will now be described with reference to FIG. 2.

[0190] In this FIG. 2, the second electrode 8 comprises a molten metal or metal oxide, such as magnesium dioxide MnO.sub.2. This electrode 8 is also regenerated thermally by heat 14 in one or more reactors 13. A product from the regeneration of the electrode 1 can be reinjected into the compartment of the electrode 8 via a pipe 12, or into the regenerator 13 of the electrode 8.

[0191] An alternative embodiment operating with liquid sulfur and producing a metal sulfide will now be described with reference to FIG. 3.

[0192] The compartments 101 of the system respectively contain the liquid metal and the liquid sulfur separated by a solid electrolyte 102. The metal ions M.sup.+ or M.sup.++ migrate through the electrolyte 102 to produce a current at the terminals of the electrodes 103. The solid metal sulfide M.sub.xS formed following the oxidation of the metal is extracted by a filter, a centrifuge or a settler 104, then heated in the heat exchanger 105 and then in the heating device 107 to which external energy is supplied. The metal sulfide M.sub.xS is thus brought to the temperature used for its transformation by electrolysis in the compartments of the regenerator 110 which are separated by an electrolyte 109. A regeneration voltage is applied to the electrodes 108 of the regenerator 110.

[0193] The regenerated metal M, preferably in liquid form, is transferred via the pipe 111 to the metal compartment of the compartments 101 of the system, while being cooled in the heat exchanger 105.

[0194] The regenerated sulfur S, preferably in gaseous form, is transferred via the pipe 112 to the sulfur compartment of the compartments 101 of the system while passing through the heat exchanger 105, in which it is cooled and liquefied.