JP5197081B2 - Cell stack device and fuel cell module - Google Patents

Description

  The present invention relates to a cell stack device and a fuel cell module including a cell stack in which a plurality of cells are arranged, a manifold that fixes the cell stack, and a gas supply pipe connected to the manifold.

  In recent years, various cell stacks in which a plurality of fuel cells are arranged and fuel cell modules in which the cell stacks are stored in a storage container have been proposed as next-generation energy.

  Hydrogen is used as the fuel gas used for power generation of the fuel cell, hydrogen gas and oxygen-containing gas are supplied into the storage container, the oxygen-containing gas is brought into contact with the oxygen-side electrode layer of the fuel cell, and hydrogen is supplied. Electric power is generated by bringing it into contact with the fuel-side electrode layer of the fuel cell and causing a predetermined electrode reaction.

  Conventionally, in a state in which a plurality of fuel cells are arranged in a row, one end (lower end) thereof is embedded in a sealing material and joined to a manifold, and current collecting members are interposed between adjacent fuel cells, respectively. However, a cell stack device configured to be joined to a fuel cell has been proposed (see, for example, Patent Document 1).

  For example, FIG. 8 shows an example of a conventional cell stack device, in which a plurality of fuel battery cells 52 are arranged in a row (a plurality of fuel battery cells 52 are arranged) at the lower end (fuel cell 52). Is embedded in the seal member 63, the cell stack 51 is fixed to the manifold 61, and a gas supply pipe 65 is connected to one end of the manifold 61 in the cell arrangement direction x. A current collecting member 53 a is interposed between adjacent fuel cells 52.

The fuel battery cell 52 has a hollow flat plate shape, and as shown in FIG. 8B, a fuel-side electrode layer 55 and a solid body are formed on one flat surface of a columnar conductive support substrate 58 having a pair of opposed flat surfaces. An electrolyte layer 56 and an oxygen-side electrode layer 54 are laminated, and an interconnector 57 is provided on the other flat surface. The fuel cell 52 has a plurality of gas passages 59, and fuel gas is supplied into the manifold 61 by the gas supply pipe 65, and passes through the gas passage 59 of the fuel cell 52 from the manifold 61. On the other hand, the air is supplied to the outside of the fuel battery cell 52. As a result, a power generation reaction occurs in the fuel battery cell 52.
Japanese Patent Laid-Open No. 2005-19240

  However, in the cell stack apparatus shown in FIG. 8, the gas supply pipe 65 is connected to one end side of the manifold 61 in the cell arrangement direction x, and the fuel gas supplied from the gas supply pipe 65 is connected to the gas supply pipe 65. Although the fuel gas can be sufficiently supplied to the fuel cell 52 on the side, the fuel gas 52 cannot be sufficiently supplied to the portion of the fuel cell 52 indicated by the broken line on the opposite side, and sufficient power generation is performed. There was a problem that could not.

  An object of the present invention is to provide a cell stack device and a fuel cell module that can supply gas to a plurality of fuel cells substantially uniformly.

The cell stack device of the present invention is necessary for the operation of the fuel cell from both sides in the arrangement direction of the fuel cell, a cell stack formed by arranging a plurality of fuel cells in at least one row, a manifold for fixing the cell stack, and two types of one gas of the gas Ri name comprises a pair of gas supply pipe connected to the manifold for supplying said plurality of fuel cells, said manifold by said gas supply tube The manifold has gas passages through which the gas supplied therein passes, and the manifold is divided into first and second manifold chambers by a partition plate extending in the arrangement direction of the fuel cells, and the fuel The battery cell straddles the first and second manifold chambers such that gas is supplied to the gas passage from the first and second manifold chambers. A first gas supply pipe is connected to the first manifold chamber, a second gas supply pipe is connected to the second manifold chamber, and the partition plate includes the first and second manifold chambers. It is characterized in that a circulation hole for circulating the water is formed .

In the cell stack device of the present invention, one of the two kinds of gases necessary for the operation of the fuel cell is supplied from both sides in the cell arrangement direction by the pair of gas supply pipes. It said one of the gas in part can be sufficiently supplied to the fuel cell located in the cell arrangement direction both end portions of the manifold can be supplied sufficiently the one gas, the one gas to a plurality of fuel cells It can be supplied almost uniformly and the power generation amount can be improved. In addition, since the power generation amount of the fuel cells located at both ends of the manifold in the cell arrangement direction increases, the temperature of the fuel cells located at both ends of the manifold in the cell arrangement direction rises, and the cell stack in the cell arrangement direction becomes uniform. Heating can be achieved.

  In the cell stack device of the present invention, the plurality of fuel cells have gas passages, and the gas supplied into the manifold by the gas supply pipes passes through the gas passages of the plurality of fuel cells. It is characterized by passing. In such a cell stack device, the present invention can be effectively used for a hollow fuel cell.

  Further, in the cell stack device of the present invention, the manifold is divided into first and second manifold chambers by a partition plate extending in the arrangement direction of the fuel cells, and the fuel cells are arranged in the gas passage. The first and second manifold chambers are arranged so as to be supplied with gas from the first and second manifold chambers, a first gas supply pipe is connected to the first manifold chamber, and the second manifold chamber is connected. And a second gas supply pipe is connected to the second gas supply pipe.

  In the cell stack device of the present invention, the gas flow passing through the first manifold chamber and the second manifold chamber is in the reverse direction, and the gas passage of the fuel cell has, for example, the first gas supply pipe side of the first manifold chamber. Since the high pressure gas and the low pressure gas on the first gas supply pipe side of the second manifold chamber are supplied, the gas supply to the fuel cells can be made uniform.

  Furthermore, the cell stack device according to the present invention is characterized in that a flow hole through which the first and second manifold chambers are formed is formed in the partition plate. In such a cell stack device, gas flows from a portion with a high gas pressure to a portion with a low gas pressure through the flow hole of the partition plate, and the gas pressure in the manifold can be made almost constant, so that the fuel cell The gas supply to can be made more uniform.

  The fuel cell module of the present invention is characterized in that the cell stack device is stored in a storage container. In such a fuel cell module, the gas supply to a plurality of fuel cells can be made almost uniform, so that the amount of power generation can be improved as a fuel cell module, and the heat equalization in the cell arrangement direction of the cell stack can be achieved. The fuel cell can be prevented from being damaged, and a fuel cell module having excellent long-term reliability can be obtained.

In the cell stack device of the present invention, one of the two kinds of gases necessary for the operation of the fuel cell is supplied from both sides of the cell arrangement direction in the manifold by the pair of gas supply pipes. said one of the gas in the arrangement direction both end portions can be sufficiently supplied to the fuel cell located in the cell arrangement direction both end portions of the manifold can be supplied sufficiently the one gas, the one to the plurality of fuel cells The gas can be supplied almost uniformly, and the amount of power generation can be improved.

  FIG. 1 shows a cell stack device 10 having a cell stack 1, (a) is a side view schematically showing the cell stack device 10, and (b) is a partially enlarged cross section of the cell stack device 10 of (a). The figure is shown. Moreover, the arrow x above the cell stack apparatus 10 in FIG. 1 indicates the cell arrangement direction of the fuel cells.

  Here, in FIG. 1, the cell stack 1 includes fuel cell cells 2 formed by laminating a fuel side electrode layer 5, a solid electrolyte layer 6, and an oxygen side electrode layer 4 on a support substrate 8. In this state, one end of the fuel battery cell 2 is embedded and joined to the sealing material 13. The cell stack 1 is bonded and fixed to a manifold body 11 having an upper surface opened in a state where the lower end portion of the fuel battery cell 2 is bonded by a sealing material 13.

  A current collecting member 3a is interposed between adjacent fuel cells 2 so that the fuel cell stack 1 is sandwiched from both sides in the arrangement direction x of the fuel cells 2 via the end current collecting members 3b. A pair of holding members 12 are provided, and these holding members 12 are erected and fixed to a manifold 11 that supplies fuel gas to the fuel cells 2. In addition, the lower part (lower end part) of the holding member 12 is also fixed to the manifold 11 with a sealing material or the like, similarly to the fuel battery cell 2.

  The cell stack 1 of the present invention is configured by electrically connecting a plurality of fuel cells 2 in series by a current collecting member 3a.

  In the present embodiment, the fuel battery cell 2 has a hollow flat plate shape, and the fuel-side electrode layer 5, the solid electrolyte layer 6, and oxygen are formed on one flat surface of a columnar conductive support substrate 8 having a pair of opposed flat surfaces. The side electrode layer 4 is laminated, and the interconnector 7 is provided on the other flat surface. Each member constituting the fuel cell 2 will be described in detail later. A plurality of gas passages 9 are formed in the length direction of the fuel cell 2 in the conductive support substrate 8 of the fuel cell 2.

  As shown in FIG. 2, one end portion of the fuel battery cell 2 is embedded and joined in the sealing material 13, and this serves as an upper lid in the opening of the manifold 11. The fuel cells need not be erected on the manifold. For example, the fuel cells may be arranged so as to extend laterally from the manifold.

  In the present invention, gas supply pipes 15a and 15b for supplying fuel gas are connected to both sides of the manifold 11 in the cell arrangement direction, and fuel gas is supplied into the manifold 11 from both sides of the cell arrangement direction. Thus, it is configured to flow through the gas passages 9 of the plurality of fuel cells 2.

  In such a cell stack apparatus, the gas supply pipes 15a and 15b are respectively connected to both sides of the manifold 11 in the cell arrangement direction x. It is possible to sufficiently supply fuel gas to the gas passages 9 of the fuel cells 2 positioned at both ends of the cell 11 in the cell arrangement direction x of the manifold 11 to generate electric power. Since the power generation amount of the fuel cells 2 located at both ends of the cell arrangement direction x increases, the reaction heat of the fuel cells 2 in this portion also increases, and the fuel cells located at both ends of the manifold 11 in the cell arrangement direction x 2 is improved, and the temperature uniformity in the cell arrangement direction x of the cell stack 1 can be achieved.

  Further, as shown in FIG. 1, since fuel gas is supplied from both sides of the cell arrangement direction x of the manifold 11 and collides with the central portion of the manifold 11, sufficient fuel gas is supplied to the fuel cells 2 in the central portion of the cell arrangement direction x. The fuel cell 2 can be cooled at the center in the cell arrangement direction x, and the temperature can be equalized in the cell arrangement direction.

  Here, other members constituting the cell stack 1 will be described below.

  The current collecting member 3a and the end current collecting member 3b can be composed of a member made of an elastic metal or alloy, or a member obtained by adding a surface treatment to a felt made of metal fiber or alloy fiber. The current collecting member 3a and the end current collecting member 3b are more preferably members made of an alloy having elasticity in order to electrically connect the fuel cells 2 having different intervals.

The oxygen side electrode layer 4 is not particularly limited as long as it is generally used. For example, the oxygen side electrode layer 4 can be formed of a conductive ceramic made of a so-called ABO ₃ type perovskite oxide. The oxygen-side electrode layer 4 needs to have gas permeability, and the open porosity is preferably 20% or more, particularly preferably in the range of 30 to 50%.
The fuel-side electrode layer 5 can be formed of a porous conductive ceramic, for example, ZrO ₂ (referred to as stabilized zirconia) in which a rare earth element is dissolved and Ni and / or NiO.

The solid electrolyte layer 6 has a function as an electrolyte for bridging electrons between the electrodes, and at the same time, has to have a gas barrier property in order to prevent leakage between the fuel gas and the oxygen-containing gas. , 3 to 15 mol% of rare earth elements are formed from ZrO ₂ as a solid solution. In addition, as long as it has the said characteristic, you may form using another material etc. The interconnector 7 can be formed from a conductive ceramic, but since it is in contact with a fuel gas (such as hydrogen) and an oxygen-containing gas (such as air), it must have reduction resistance and oxidation resistance. Therefore, a lanthanum chromite-based perovskite oxide (LaCrO ₃ -based oxide) is preferably used. The interconnector 7 must be dense in order to prevent leakage of fuel gas passing through the fuel gas passage 9 formed in the conductive support substrate 8 and oxygen-containing gas flowing outside the conductive support substrate 8; It is preferable to have a relative density of 93% or more, particularly 95% or more.

  The conductive support substrate 8 is a plate-like piece elongated in the standing direction, and has both flat surfaces and both sides of a semicircular shape. A plurality (six in FIG. 1B) of gas passages 9 penetrating through the conductive support substrate 8 in the length direction are formed. The conductive support substrate 8 is required to be gas permeable in order to allow the fuel gas to permeate to the fuel side electrode layer 5. For example, a porous conductive ceramic or cermet can be used.

FIG. 3 shows an embodiment of a reference example of the present invention. In this embodiment, the manifold 19 is divided into a first manifold chamber 19a and a second manifold chamber 19b by a partition plate 21 extending in the cell arrangement direction x. The fuel cell 2 has the first and second gas passages so that the gas from the first and second manifold chambers 19a and 19b is supplied to the gas passage 9 of the fuel cell 2 as shown by a one-dot chain line in FIG. The two manifold chambers 19a and 19b are disposed across.

  That is, the three gas passages 9 of the fuel cell 2 are connected to the first manifold chamber 19a (hereinafter sometimes referred to as communication), and the other three gas passages 9 of the fuel cell 2 are connected to the second manifold chamber 19a. It communicates with 19b.

  The first gas supply pipe 15a and the second gas supply pipe 15b are provided on opposite sides of the manifold 11 in the cell arrangement direction x, and the first gas supply pipe 15a is connected to and communicates with the first manifold chamber 19a. A second gas supply pipe 15b is connected to and communicates with the second manifold chamber 19b.

  In such a cell stack apparatus, the gas flow passing through the first manifold chamber 19a and the second manifold chamber 19b is in the reverse direction, and is disposed, for example, on the first gas supply pipe 15a side of the first manifold chamber 19a. In the gas passage 9 of the fuel cell 2, high pressure gas on the first gas supply pipe 15a side of the first manifold chamber 19a and low pressure gas on the first gas supply pipe 15a side of the second manifold chamber 19b Therefore, the gas supply to the fuel cells in the cell arrangement direction x can be made uniform. As a result, the power generation amount of the fuel cells 2 located at both ends of the cell 11 in the cell arrangement direction x of the manifold 11 increases, so that the reaction heat also increases and the fuel cells 2 located at both ends of the cell arrangement direction x of the manifold 11 increase. The temperature can be improved, and soaking in the cell arrangement direction x of the cell stack 1 can be achieved.

Figure 4 shows an example of embodiment of the present invention, in this embodiment, the partition plate 21 of the cell stack device of FIG. 3, first, passing holes 23a for circulating the second manifold chamber 19a, 19b, 2
3b is formed. In such a cell stack device, the flow of gas passing through the first manifold chamber 19a and the second manifold chamber 19b is in the reverse direction, and from the high gas pressure portions of the first and second manifold chambers 19a and 19b, Gas flows through the flow holes 23a and 23b of the plate 21 to a portion where the gas pressure is low, the gas pressure in the manifold 19 can be made substantially constant, and the gas supply to the fuel cells can be made more uniform.

  The fuel cell module according to the present invention is configured by housing the above-described cell stack device in a storage container. Fuel gas is supplied to the manifold 19 via the gas supply pipes 15a and 15b, and the gas passage of the fuel cell 2 is provided. 9, the oxygen-containing gas, for example, air is supplied to the outside of the fuel battery cell 2 and is discharged to the upper side of the fuel battery cell, for example, surplus fuel gas is burned. Is done. Then, power generation is performed at the portion where the fuel side electrode layer 5, the solid electrolyte layer 6 and the oxygen side electrode layer 4 overlap.

  In such a fuel cell module, the gas supply to the fuel cell 2 can be made almost uniform, so that the power generation amount can be improved as a fuel cell module, and the heat equalization in the cell arrangement direction x of the cell stack can be achieved. The damage of the fuel cell can be suppressed, and the long-term reliability can be improved.

  Although the present invention has been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and improvements can be made without departing from the scope of the present invention.

  For example, as shown in FIG. 5, a reformer 25 for reforming city gas or the like is disposed above the cell stack 1, and the reformer 25 is heated by the heat of the cell stack 1 to reform the cell. By using the stack device, high temperature fuel gas can be introduced from both sides of the cell arrangement direction x of the manifold, the fuel cells 2 on both sides can be heated, and the gas is heated at the center of the cell arrangement direction x. The fuel gas that has been exchanged and has a temperature lower than both sides in the cell arrangement direction x is supplied to the fuel cell 2 in the center of the cell arrangement direction x, and the fuel cell 2 in the center can be cooled. The soaking of the cell stack 1 can be further improved. In addition, not only when the reformer 25 is disposed above the cell stack 1, but also when the reformer 25 is disposed on the side or below the cell stack 1, there are some effects.

  Further, in the above embodiment, the cell stacks 1 arranged in a row in the manifolds 11 and 19 are provided. However, as shown in FIG. 6, even when the cell stacks 1 in two rows are provided in one manifold, The same effect can be obtained.

  Further, in the above embodiment, the cell stack device using the hollow flat plate fuel cell has been described, but the same effect as described above can be obtained even with a cylindrical fuel cell. Furthermore, the same effect as described above can be obtained even in a cell stack device using a flat fuel cell, for example, a flat fuel cell as shown in FIG.

  That is, in the cell stack device of FIG. 7, a plurality of disk-shaped fuel cells 27 are arranged to form a stack 28, and the central portion of the disk-shaped fuel cells 27 penetrates the stack 28. A manifold 29 is provided. The manifold 29 is provided with gas supply pipes 31 on both sides in the cell arrangement direction x, gas is supplied from both sides of the manifold 29 in the cell arrangement direction x, and gas is supplied radially to the fuel cells 27. It is configured as follows. Even in such a cell stack, fuel gas can be sufficiently supplied to the fuel cells 27 located at both ends of the manifold 29 in the cell arrangement direction x.

  Further, the example in which the gas supply pipes 15a and 15b are connected to the both end faces of the manifold 11 in the cell arrangement direction x has been described. However, the present invention is configured to supply gas from both sides of the cell arrangement direction x in the manifold. If it is good. For example, a gas supply pipe can be connected to the side surfaces of both ends of the manifold 11 in the cell arrangement direction x, and gas can be supplied from both sides of the cell arrangement direction x.

An example of the cell stack apparatus of this invention is shown, (a) is a side view which shows a cell stack apparatus schematically, (b) is a partial expanded sectional view of (a). It is a schematic sectional drawing which shows a cell stack. It is sectional drawing which shows the form of the reference example of this invention which has arrange | positioned the partition plate to the manifold. It is sectional drawing which shows the form of an example of this invention which formed the through-hole in the partition plate of the manifold. It is a side view which shows roughly the cell stack apparatus which has arrange | positioned the reformer above the cell stack. It is sectional drawing which provided the cell stack of two rows in the manifold. It is a side view at the time of applying this invention to a disk shaped fuel cell. An example of the conventional cell stack apparatus is shown, (a) is a side view schematically showing the cell stack apparatus, and (b) is a partially enlarged sectional view of (a).

Explanation of symbols

1, 28: Cell stack 2, 27: Fuel cell 9: Fuel gas passage 10: Cell stack device 11, 26, 29: Manifold 15a, 31a: First gas supply pipe 15b, 31b: Second gas supply pipe 19a: 1st manifold chamber 19b: 2nd manifold chamber 21: Partition plate 23a, 23b: Flow hole x: Cell arrangement direction

Claims (2)

A cell stack in which a plurality of fuel cells are arranged in at least one row, a manifold for fixing the cell stack, and two kinds of gases necessary for the operation of the fuel cell from both sides in the arrangement direction of the fuel cells. Ri Na and and a pair of gas supply pipe connected to the manifold for supplying one gas, the plurality of fuel cells, gas supplied into the manifold by the gas supply pipe is passed The manifold is divided into first and second manifold chambers by a partition plate extending in the arrangement direction of the fuel cells, and the fuel cells are arranged in the gas passage. The first manifold is disposed across the first and second manifold chambers such that gas is supplied from the first and second manifold chambers. A first gas supply pipe is connected to the chamber, a second gas supply pipe is connected to the second manifold chamber, and a flow hole through which the first and second manifold chambers are circulated is formed in the partition plate. the cell stack and wherein the being. A fuel cell module comprising the cell stack device according to claim 1 stored in a storage container.

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