FUEL CELL DEVICE

Abstract

The invention relates to a fuel cell device comprising a fuel cell unit (10) which comprises at least two fuel cells (12, 14) and an interconnection unit (16) which is provided to serially interconnect the at least two fuel cells (12, 14). According to the invention, the at least one interconnection unit (16) comprises at least two layers (18, 20) which are made from different materials.

Claims

1. A fuel cell device having a fuel cell unit (10) which comprises first and second fuel cells (12, 14) and an interconnector unit (16) serially interconnecting the fuel cells (12, 14), characterized in that the at least one interconnector unit (16) has first and second laminae (18, 20) which are formed of materials different from one another.

2. The fuel cell device as claimed in claim 1, characterized in that the first lamina (18) is formed of a manganese-based perovskite.

3. The fuel cell device as claimed in claim 1, characterized in that the second lamina (20) is formed of a nickel-based perovskite.

4. The fuel cell device as claimed in claim 1, characterized in that the fuel cell unit (10) comprises at least one cathode layer (22) forming cathodes (24, 26) of the fuel cells (12, 14), at least one anode layer (28) forming anodes (30, 32) of the fuel cells (12, 14), and at least one electrolyte layer (34) forming electrolytes (36, 38) of the fuel cells (12, 14).

5. The fuel cell device as claimed in claim 4, characterized in that the fuel cells (12, 14) within the fuel cell unit (10) are disposed in such a way that one of the cathodes (24) of the first fuel cell (12) at least partially overlaps one of the anodes (32) of the second fuel cell (14).

6. The fuel cell device at least as claimed in claim 4, characterized in that the interconnector unit (16) is disposed within the electrolyte layer (34) of the fuel cell unit (10).

7. The fuel cell device as claimed in claim 6, characterized in that the first lamina (18) of the interconnector unit (16) points in the direction of the at least one anode layer (28), and the second lamina (20) of the interconnector unit (16) points in the direction of the at least one cathode layer (22).

8. The fuel cell device as claimed in claim 1, characterized by at least one base body (40) on which the fuel cell unit (10) is disposed.

9. (canceled)

10. The fuel cell device as claimed in claim 2, characterized in that the second lamina (20) is formed of a nickel-based perovskite.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Further advantages will become apparent from the following description of the drawing. The drawing shows an exemplary embodiment of the invention. The drawing, the description, and the claims contain numerous features in combination. The skilled person will also look at the features individually, usefully, and assemble them to form rational further combinations.

[0017] FIG. 1 shows a schematic cross section through a fuel cell device having a fuel cell unit which comprises at least two fuel cells which are serially interconnected by means of a bilaminar interconnector unit.

DETAILED DESCRIPTION

[0018] FIG. 1 shows a schematic cross section through a fuel cell device 46, which is here shown only in part. The fuel cell device 46 comprises a fuel cell unit 10, which here, as an example, comprises two serially connected fuel cells 12, 14. The fuel cells 12, 14 are connected in series via an interconnector unit 16.

[0019] As shown by FIG. 1, the fuel cell unit 10 is designed as a multilaminar layer system, with the fuel cells 12, 14 formed substantially alongside one another. The fuel cell unit 10 here comprises a cathode layer 22, an electrolyte layer 34, and an anode layer 28. The cathode layer 22 here forms the cathodes 24, 26 of the fuel cells 12, 14. The anode layer 28 here forms the anodes 30, 32 of the fuel cells 12, 14. The electrolyte layer 34 here forms the electrolytes 36, 38 of the fuel cells 12, 14.

[0020] The interconnector unit 16 is disposed entirely within the electrolyte layer 34. In particular, the interconnector unit 16 is disposed in such a way that the cathode 24 of the first fuel cell 12 is connected in series with the anode 32 of the second fuel cell 14 via the interconnector unit 16. The electrolyte 36 of the first fuel cell 12 here is separated, in particular in an ionically insulating manner, by the interconnector unit 16 from the electrolyte 38 of the second fuel cell 14.

[0021] FIG. 1 illustrates further how the cathodes 24, 26 of the fuel cells 12, 14 are separated from one another by an electrically and ionically insulating region 42, and the anodes 30, 32 of the fuel cells 12, 14 by at least one electrically and ionically insulating region 44. In the embodiment shown in FIG. 1, moreover, the cathodes 24, 26 and the anodes 30, 32 of the fuel cells 12, 14 are formed by the cathode layer 22 and by the anode layer 28, respectively, in such a way that the cathode 24 of the first fuel cell 12 partially overlaps the anode 32 of the second fuel cell 14. Within the overlapping region, the interconnector unit 16 here is disposed in the electrolyte layer 34. Alternatively, however, there may be no overlapping of an anode and a cathode.

[0022] FIG. 1 shows, furthermore, that the fuel cell device 46 has a base body 40. The base body 40 may be formed, for example, of one or more ceramic and/or vitreous materials. In principle, the base body 40 may be either a base body of tubular design or else a base body of planar design. The fuel cell device 46, therefore, may be formed either as a planar fuel cell device or else, preferably, as a tubular fuel cell device. The fuel cell unit 10 here may be applied in particular on an inside or on an outside, but preferably, as shown here, on the inside, of the base body 40. As illustrated by FIG. 1, the cathodes 24, 26 of the fuel cells 12, 14 and/or the cathode layer 22 of the fuel cell unit 10 adjoin the base body 40. The anodes 30, 32 of the fuel cells 12, 14 and/or the anode layer 28 of the fuel cell unit 10 here is open or is freely accessible. In the section adjoining the fuel cells 12, 14, the base body 40 has gas-permeable pores and/or openings.

[0023] The interconnector unit 16 is bilaminar. A first lamina 18 of the interconnector unit 16 is formed at least substantially of a manganese-based perovskite. The manganese-based perovskite has the general chemical formula La.sub.1−xSr.sub.xA.sub.yMn.sub.1−yO.sub.3, where 0.05<x<0.6, 0.05<y<0.6, and A=scandium (Sc), titanium (Ti), niobium (Nb) or tantalum (Ta). A second lamina 20 of the interconnector unit 16 is formed at least substantially of a nickel-based perovskite. The nickel-based perovskite has the general chemical formula LaNi.sub.xFe.sub.1−xO.sub.3, where 0.05<x<0.6. The laminae 18, 20 of the interconnector unit 16 are disposed in such a way that the first lamina 18 of the interconnector unit 16 points in the direction of the anode layer 28, and the second lamina 20 of the interconnector unit 16 points in the direction of the at least one cathode layer 22.

[0024] Through the first lamina 18, which is formed at least substantially of the manganese-based perovskite, the interconnector unit 16, particularly in an anodic atmosphere, has a sufficiently high conductivity (5 S/cm at 850° C.). At the same time, the first lamina 18 protects the underlying second lamina 20, which is formed at least substantially of the nickel-based perovskite, from harmful effects of the anodic atmosphere. By virtue of the good sintering properties of the nickel-based perovskite, the second lamina 20 is of advantageously gastight design, thereby making it possible to prevent emergence of fuel gas from the fuel cell device 46, advantageously. Through the bilaminar construction of the interconnector unit 16, the positive physical properties of the manganese-based perovskite of the first lamina 18 and of the nickel-based perovskite of the second lamina 20 are combined advantageously with one another.