JPH0752653B2 - Lower holder for fuel cell - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a holder arranged above and below a stack in a fuel cell used in an energy sector for directly converting chemical energy of a fuel into electric energy.
It concerns the lower holder.

[Prior Art] Among the fuel cells proposed so far, for example,
The molten carbonate fuel cell has a tile (electrolyte plate) a formed by impregnating a molten carbonate as an electrolyte in a porous material as an electrolyte, a cathode (oxygen electrode) b and an anode (fuel electrode), as shown in FIG. It is sandwiched from both sides by c and c, and the oxidizing gas is supplied to the cathode b side and the fuel gas is supplied to the anode c side so that power generation is performed by the potential difference generated between the cathode b and the anode c. C, each cell C is laminated in multiple layers via a separator d to form a stack S, and the stack S is sandwiched by upper and lower holders (not shown) and the whole is tightened with a predetermined tightening force to form a cathode. b and the anode c are brought into uniform contact with the tile a.

In the above fuel cell, in the case of the internal manifold type, the flow passage holes e and f on the supply side and the discharge side of the oxidizing gas OG and the supply side and the discharge of the fuel gas FG are provided in the peripheral portions of the tile a and the separator d. Each of the flow path holes g and h on the side is provided, and each gas is allowed to flow through the gas passage i formed by the unevenness provided on the front and back surfaces of each separator d.

Of the upper and lower holders used in the internal manifold type fuel cell, the lower holder is, as shown in FIG. A flow path hole g for use is provided, a flow path hole f for discharging the oxidizing gas and a flow path hole h for discharging the fuel gas are provided on the other side of the peripheral portion, and the gas is flowed from one side to the other side on the upper surface. For this purpose, the gas passage i is formed by unevenness, and headers j and k on the supply side and the discharge side of the oxidizing gas and the fuel gas are provided outside the peripheral portion of the lower holder A having such a configuration. Headers 1 and m on the supply side and the discharge side are provided, and headers j and k on the supply / discharge side of the oxidizing gas and flow path holes e and f on the supply / discharge side of the oxidizing gas are connected to each other by a connecting pipe n.
And o, and the headers 1 and m for supplying and discharging the fuel gas and the flow path holes g and h for supplying and discharging the fuel gas are connected by the connecting pipes p and q. Further, as shown in FIG. 8, the lower holder A having the above-described structure has an integral structure with a heater plate r arranged on the lower surface side, and the heater plate r is provided on the heat insulating material t on the lower bed s with the honest plate u interposed therebetween. The gas supplied from the header j or 1 to the lower holder A and flown to the discharge side can be heated by the heater v of the lower heater plate r.

[Problems to be Solved by the Invention] However, it is known that the performance of a fuel cell can be improved under pressure.
As shown schematically in the figure, the entire fuel cell FC is housed in a pressure vessel w of a certain size, and the pressure inside the vessel w is set to a pressure slightly higher than the pressure inside the fuel cell. Since the fuel cell is placed under pressure as described above, when the fuel cell FC is housed in the pressure container w, it is necessary to make the fuel cell compact. However, in the conventional fuel cell, the fuel cell FC shown in FIG. Also, as shown in FIG. 8, headers j, k, l, and m are symmetrically projected on both sides of the lower holder A, and the overall width dimension is large. Had to prepare.

Therefore, the present invention, without providing a header on both sides,
A gas flow path is defined in the inner space, the inner space is covered with a heater plate, the heater plate is integrated with the lower holder, and the gas flowing in the inner space is affected by the heater immediately above. There is no such thing, and it tries to make the whole compact.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides, on opposite sides of a peripheral portion, flow passage holes for supplying and discharging an oxidizing gas and flow passage holes for supplying and discharging a fuel gas. A heater plate having a substantially square shape and having a heater mounted thereon, and a box shape having a required depth to divide the internal space into partition parts on the supply side and the discharge side and the periphery of the heater plate. And a lower holder main body formed by partitioning one of the flow passage holes in each of the distribution portions at a peripheral portion position corresponding to the flow passage hole for oxidizing gas and the flow passage hole for fuel gas. The upper surface of the lower holder main body is covered with a heater plate to form an integral structure, and the gas duct communicating with each distribution portion formed in the internal space of the lower holder main body is partitioned from each distribution portion. It is equipped with a gas duct that communicates with the compartment as another gas distributor. In addition, a heat insulating material is arranged on the lower surface of the heater plate.

[Operation] Since the inside of the lower holder main body is partitioned by the partition wall to divide and form the respective supply and discharge side distributors of oxidizing gas and fuel gas, connect the gas duct to the lower holder main body. The oxidizing gas and the fuel gas can be supplied and discharged only by itself, and it is not necessary to provide an external header as in the conventional method, and the entire structure can be made compact. As a result, the pressure type fuel cell can be easily housed in a small pressure vessel.

Since the flow direction of the gas that has entered the inner space of the lower holder body is regulated by the partition wall, if there is a heater at the upper part, there will be a portion heated by the heater and a portion not heated, and the temperature distribution will be uneven. However, since there is a heat insulating material on the lower surface of the heater plate, the influence of the heater can be eliminated.

EXAMPLES Examples of the present invention will be described below with reference to the drawings.

1 to 4 show an embodiment of the lower holder of the present invention, in which the heater plate 1 and the lower holder body 2 having a space through which a gas flows therein are integrally structured to distribute gas inside. The part is integrally formed.

The heater plate 1 also serves as a conventional honest plate,
A plurality of heaters 3 are inserted in parallel, an oxidizing gas supply side flow path hole 4 and a fuel gas supply side flow path hole 5 are provided on one side of the peripheral portion, and an oxidizing gas is provided on the other side of the peripheral portion. The gas discharge side flow path hole 6 and the fuel gas discharge side flow path hole 7 are provided to form a substantially square shape.

The lower holder body 2 has a box-like shape having an internal space of a required depth, in which a side plate is erected on a substantially square bottom plate having an outer dimension slightly smaller than that of the heater plate 1. The central portion of the internal space is partitioned by a partition wall 8 to divide into gas supply side and discharge side distribution sections 9 and 10, and in the gas supply side distribution section 9, as shown in FIG.
A partition wall 11 partitions the peripheral portion of the heater plate 1 corresponding to the fuel gas supply side flow passage hole 5 from the portion corresponding to the oxidizing gas supply side flow passage hole 4 to form a fuel gas distribution portion. The chamber 13 is formed independently, and similarly, in the distribution part 10 on the gas discharge side, the portion corresponding to the fuel gas discharge side flow path hole 7 in the peripheral portion of the heater plate 1 is connected to the oxidizing gas discharge side flow. A partition wall 12 separates from the portion corresponding to the passage hole 6 to independently form a compartment 14 as a fuel gas distribution portion, and further, on each side wall, gas ducts 15 and 16 on the supply side and a discharge side are formed. The gas ducts 15 on the supply side are connected to the distribution section 9 on the oxidizing gas supply side, and the gas ducts 16 on the supply side are connected to the compartments 13 serving as the distribution section on the fuel gas supply side. While communicating with each other, the gas duct 17 on the exhaust side is connected to the distributor 10 on the oxidizing gas exhaust side, The gas ducts 18 on the outlet side are configured to communicate with the compartments 14 serving as the distributors on the fuel gas discharge side. The oxidizing gas OG enters the distributor 9 from the gas ducts 15 on the supply side, and then the heater plate 1 The heater is distributed to a portion corresponding to the supply-side flow passage hole 4, enters the supply-side flow passage hole 4 of the heater plate 1, rises, is supplied to the cathode side of each cell, and descends through the discharge-side flow passage hole. From the discharge-side flow path hole 6 of the plate 1, it flows out to the discharge-side distribution portion 10 and is discharged from here through the discharge-side gas duct 17, while
After entering the compartment 13 from the gas duct 16 on the supply side, the fuel gas FG rises in the supply side passage hole 5 of the heater plate 1 and is supplied to the anode side of each cell, and descends through the discharge side passage hole. Then, the heater plate 1 enters into the compartment 14 through the discharge side flow path hole 7 and is discharged from there through the discharge side gas duct 18. Furthermore, a heat insulating material 19 is provided on the entire lower surface of the heater plate 1 located on the upper surface of the lower holder body 2 so that the gas flowing under the heater plate 1 is affected by the heater 3. Try not to.

When the lower holder for a fuel cell of the present invention is used, the lower holder body 2 is placed on the lower bed 20 via a heat insulating material 21 as shown in FIG.
5,16,17,18 are respectively connected to the corresponding gas pipes or hoses, and the tile a is sandwiched between both electrodes of the cathode b and the anode c from both sides, and the oxidizing gas is supplied to the cathode b side. A fuel cell stack S formed by stacking cells C, each of which supplies fuel gas to the anode c side, in multiple layers via a separator d is placed on the heater plate 1 via an end separator 22. An upper holder (not shown) is arranged on the stack S so that the whole is tightened with a predetermined tightening force.

Now, when supplying and discharging the oxidizing gas and the fuel gas,
Gas distributor 9 formed in the inner space of the lower holder body 2,
Try to do it through 10,13,14. In this case, the oxidizing gas is supplied from the gas duct 15 on the supply side to the lower holder body 2
When it is supplied to the supply side distribution unit 9 inside, it is distributed to the portion of the heater plate 1 communicating with the oxidizing gas supply side flow path hole 4 and rises, and is supplied to the cathode b side for each cell of the fuel cell stack S. After being discharged to the discharge side, the discharge side flow path hole of each cell descends and passes through the discharge side flow path hole 6 of the heater plate 1 into the discharge side distribution portion 10 of the lower holder body 2, The gas is discharged from the discharge side distribution unit 10 through the gas duct 17. on the other hand,
When the fuel gas enters the partitioned chamber 13 in the lower holder body 2 from the gas duct 16 on the supply side, the partitioned chamber 13 communicates with the supply-side flow passage hole 5 of the heater plate 1, so that the partitioned chamber
The fuel gas entering 13 rises as it is, is supplied to the anode c side for each cell of the fuel cell stack S and is flown to the discharge side, and then descends through the discharge side flow passage hole of each cell to move to the heater plate 1 It passes through the discharge-side flow path hole 7 and enters the partitioned chamber 14 in the lower holder body 2, from which it is discharged through the gas duct 18.

As described above, in the lower holder of the present invention, the lower holder main body 2 is formed into a box shape to form a space between the lower holder body 2 and the heater plate 1 covering the upper surface, and the oxidizing gas supply side and the discharge side distribution are distributed in the space. Parts 9 and 10 and compartments 13 and 14 serving as distribution parts on the fuel gas supply side and the discharge side are formed in the respective distribution parts, and conventional headers j, k, l, m (see FIG. 7) Since it has a structure in which the equivalent to the above is incorporated inside the lower holder main body 2, it can be compactly assembled without any externally projecting headers j, k, l, m, etc. Therefore, it is possible to eliminate the need for a large pressure container even when the pressure container is housed in the pressure container.

In addition, since the flow of both the oxidizing gas and the fuel gas is regulated and the gas flows under the heater plate 1, the gas is heated by the heater 3 when the gas is supplied and discharged. There is a risk that the temperature distribution will be uneven due to the presence and absence of the heat insulating material. However, in consideration of this point, in the present invention, the heat insulating material is provided inside the lower holder body 2.
19 is inserted so that the heater 3 does not affect the gas.

The present invention is not limited to the above-described embodiment, and for example, the supply side flow passage holes 4 and 5 for the oxidizing gas and the fuel gas are provided on one side of the peripheral portion of the heater plate 1, and An example is shown in which the discharge side flow passage holes 6 and 7 for the oxidizing gas and the fuel gas are provided on the other side of the section, but the flow passage holes for supply and discharge should be provided so that the oxidizing gas and the fuel gas are in opposite flows. What you can do,
Needless to say, various changes can be made without departing from the scope of the present invention.

[Effects of the Invention] As described above, according to the lower holder for a fuel cell of the present invention, the heater plate is integrally attached to the upper surface of the lower holder body formed in a box shape having a required depth, and the lower holder body is also attached. The inner space formed between the heater plate and the heater plate is partitioned by a partition wall to form a gas distribution part, and a heat insulating material is further placed in the inner space so that the gas flowing in the lower holder body is above the heater. Since it is not affected by, the inside of the lower holder main body can be used as a passage for the gas supply side and the gas discharge side, and the header that was conventionally outside the lower holder can be eliminated, The overall external dimensions can be made smaller than the conventional method, making it compact, and it can be easily stored in a small pressure container when it is used as a pressurizing type. Since the flow of the generated gas is regulated, there is a possibility that uneven temperature distribution may occur due to the influence of the upper heater, but the fear is eliminated by the heat insulating material placed inside, so that uneven temperature distribution does not occur. And so on.

[Brief description of drawings]

1 is a plan view of a lower holder for a fuel cell according to the present invention, FIG. 2 is a view taken along the line II-II in FIG. 1, and FIG. 3 is a line III-I in FIG.
II arrow view, FIG. 4 is a side view from the IV direction of FIG. 3, 5
FIG. 1 is a side view showing an example of assembly using the lower holder for a fuel cell of the present invention, FIG. 6 is a sectional view showing an example of a conventional example, and FIG. 7 is a schematic plan view of a conventional lower holder for a fuel cell. FIG. 8 is a schematic side view showing an example of assembly using a conventional lower holder, and FIG. 9 is a schematic view showing an example of a pressurized fuel cell. 1 ... Heater plate, 2 ... Lower holder body, 3 ... Heater, 4 ... Oxidizing gas supply side flow path hole, 5 ... Fuel gas supply side flow path hole, 6 ... Oxidizing gas discharge side flow path hole , 7 ... Fuel gas discharge side flow path hole, 8 ... Partition wall, 9 ... Supply side distribution part, 10 ... Discharge side distribution part, 11, 12 ... Partition wall, 13, 14 ...
… Compartments (distributor), 15,16,17,18 …… Gas duct, 19
…… Insulation material.

Claims (1)

[Claims] 1. A lower holder body having a box-shaped heater plate having a required depth, the heater plate having flow passage holes on the supply and discharge sides of the oxidizing gas and the fuel gas in the peripheral portion and having heaters mounted therein. An inner space is formed by integrally fixing to the upper surface, and the inner space is divided into a gas supply side and a gas discharge side distribution portion by a partition wall, and the oxidizing gas and fuel in the peripheral portion of the heater plate are also divided. A partition chamber that distributes only one of the oxidizing gas and the fuel gas at a portion corresponding to the flow path hole on each gas supply / discharge side is partitioned and formed in the distribution unit, and further, each distribution unit and each partition chamber. A lower holder for a fuel cell, characterized in that a gas duct is connected to each of the above and a heat insulating material is put in the internal space.