JPH1079256A - Fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prolong the lifetime of and enhance the power generating efficiency of a fuel cell of laminate type in which a cooling part having a passage for a coolant to flow is interposed, by making uniform the temp. distribution over the surface of each unit cell. SOLUTION: This fuel cell comprises an alternate laminate of unit cells 5 each being formed by arranging an anode 3 and cathode 4 on an electrolytic matrix 2 and composite separators 9 each structured so that porous base boards 7 and 8 are installed on the surfaces of a separator plate 6, and one cooling part 11 is interposed each time a predetermined number of unit cells 5 are laminated, and the cooling part 11 is formed by interposing a partition plate 10 between adjoining composite separators 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell comprising a cell stack in which unit cells each having an anode and a cathode disposed with an electrolyte layer interposed therebetween and a gas separator are alternately stacked, and a cooling unit is interposed. In particular, it relates to improvement of a cooling section.

[0002]

2. Description of the Related Art A stacked fuel cell comprises a cell stack in which a unit cell having an anode and a cathode disposed via an electrolyte layer and a separator are alternately stacked, and an anode gas (hydrogen-rich) is provided on the anode of each unit cell. (A fuel gas) is supplied to the cathode, and a cathode gas (air) is supplied to the cathode to cause an oxidation-reduction reaction, thereby generating power.

[0003] Since this oxidation-reduction reaction is an exothermic reaction, it is necessary to forcibly cool the fuel cell in order to keep the cell temperature during operation at an appropriate temperature. Therefore, conventionally, a method of cooling the fuel cell by feeding an excess amount of air than is necessary for the reaction has been used, but in this cooling method, temperature variation in the cell stack tends to occur, and particularly, In addition, the temperature of the unit cells stacked in the center tends to increase.

[0004] Therefore, a system for cooling a fuel cell by interposing a cooling plate formed along a stacking surface with a passage for a cooling medium such as air or water for every predetermined number of stacked unit cells. This cooling method can reduce the temperature difference in the stacking direction.

[0005]

However, even in such a fuel cell in which the cooling plate is interposed, there still remains a problem that the temperature in the plane of the unit cell varies, and the maximum temperature in the plane of the unit cell differs from that in the unit cell. There may be a difference of about 30 ° C. from the minimum temperature. If the in-plane temperature of the unit cell varies widely, the current density increases in a high-temperature portion, and the unit cell is likely to deteriorate. Also, if the in-plane temperature of the unit cell varies widely, the operating temperature of the fuel cell may have to be set lower in order to protect the components of the fuel cell, leading to a decrease in power generation efficiency. There is also.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has been made in consideration of the above-described temperature distribution in a unit cell of a stacked fuel cell having a cooling unit having a passage through which a cooling medium flows. It is intended to contribute to prolonging the life of the fuel cell and improving the power generation efficiency by making the fuel cell uniform.

[0007]

In order to achieve the above-mentioned object, the present invention provides a fuel cell system comprising: a unit cell in which an anode and a cathode are arranged on an electrolyte layer; In a fuel cell including a cell stack in which one or more cooling units are interposed, a first passage through which a cooling medium flows and a cooling medium flows in a direction different from the first passage through at least one of the cooling units. A second passage was provided along the stacking surface. Thereby, the temperature distribution in the plane of the unit cell can be made uniform.

Here, if hydrogen gas is supplied to at least one of the first and second passages, an excellent cooling effect can be obtained. Further, a gas is supplied to the first passage from an anode gas supply source that supplies an anode gas to the anode,
If a gas is supplied to the second passage from a cathode gas supply source that supplies a cathode gas to the cathode, there is no need to provide a separate supply source for the cooling medium.

Further, if a gas recovery means for recovering the gas passing through the first passage and mixing it with the gas supplied from the anode gas supply source to the anode is provided, the gas used as the cooling medium can be recovered. It can be used as an anode gas. In addition, the above-described cooling unit can be easily configured by interposing a gas-impermeable and conductive partition plate between two adjacent gas separation plates in the stacking direction.

The material of the partition plate is preferably selected from the group consisting of glassy carbon, graphitized carbon and a mixture thereof.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a fuel cell according to the present invention will be specifically described with reference to the drawings. [1] Description of Battery Configuration (Embodiment 1) FIG. 1 is an assembly diagram showing a configuration of a phosphoric acid type fuel cell according to the present embodiment.

The fuel cell 1 has an electrolyte matrix 2
Cell 5 in which an anode 3 and a cathode 4 are arranged
And a composite separator 9 in which a porous substrate 7 and a porous substrate 8 are arranged on both surfaces of the separator plate 6 alternately, and the cooling unit 11 is inserted every time a predetermined number of unit cells 5 are stacked. The cooling unit 11 is configured by inserting a partition plate 10 between adjacent composite separators 9.

That is, in the fuel cell 1, a laminated unit in which a predetermined number of unit cells 5 are inserted one by one between a plurality of composite separators 9, and then one partition plate 10 is inserted, is repeated. It is configured. Although not shown, the fuel cell 1 is fastened by a pair of end plates disposed at both ends in the stacking direction, and supplies anode gas and cathode gas to the respective anodes 3 and cathodes 4 on four side surfaces. An external manifold for recovery is crowned.

The total number of cells 5 stacked in the fuel cell 1 is set according to the voltage to be output. In FIG. 1, five single cells 5 are stacked between the adjacent cooling units 11, but the number of the single cells 5 stacked between the adjacent cooling units 11 is An appropriate number is set according to the cooling capacity. Electrolyte matrix 2
Is a rectangular sheet obtained by binding silicon carbide with a fluororesin and impregnated with phosphoric acid.

Both the anode 3 and the cathode 4 form a sheet by binding carbon particles carrying a platinum catalyst or a platinum alloy catalyst with a fluororesin, and the sheet is made from water-repellent carbon fibers. It is crimped on carbon paper. The separator plate 6 includes the electrolyte matrix 2
A flat plate having the same size as that of the flat plate is provided with a strip-shaped edge seal portion 6a on one surface side (lower surface side in FIG. 1) along a pair of opposing sides, and on the rear surface side (FIG. 1). On the upper surface), a strip-shaped edge seal portion 6b is provided along a pair of opposing sides orthogonal to this, and the whole is formed of dense glassy carbon.

The porous substrate 7 is a rectangular plate fitted between a pair of edge seal portions 6a of the separator plate 6, and has a large number of gas channels 7a formed on the surface thereof in parallel with the edge seal portions 6a. The ribs 7b are formed in the gaps, and the porous substrate 8
A rectangular plate fitted between a pair of edge seal portions 6b, on the surface of which a number of gas channels 8a are carved in parallel with the edge seal portions 6b and ribs 8b are formed in the gaps. It is.

The porous substrates 7 and 8 have the same size as the anode 3 and the cathode 4. Porous substrate 7
Are in contact with the surface of the anode 3, and the ribs 8b of the porous substrate 8 are in contact with the surface of the cathode 4, so that electricity generated by the unit cell 5 is collected by the porous substrates 7, 8. It is supposed to be.

The partition plate 10 interposed between the two composite separators 9 is a dense flat plate having the same size as the separator plate 6 and has a function of separating hydrogen gas and air and a function of separating the two composite separators 9. In order to fulfill the function of electrically connecting the battery, the material is required to be gas-impermeable and conductive, and furthermore, it must have some elasticity in order to absorb the stress accompanying the temperature change of the battery. preferable.

As a preferable material used for the partition plate 10, a plate made of glassy carbon, graphitized carbon, or a mixture thereof can be used. In addition, plates made of various metals or conductive ceramics can be used. Can also. The graphitized carbon plate can be manufactured by laminating and pressure-bonding resin-impregnated base paper, firing it, and graphitizing it.

In the fuel cell 1 configured as described above,
During operation, hydrogen is supplied from an external hydrogen supply source to the hydrogen supply manifold, and hydrogen gas is distributed from the hydrogen supply manifold to each of the gas channels 7a. On the other hand, air is supplied from an external fan to the air supply manifold, and the air is distributed from the air supply manifold to the gas channels 8a.

In each of the cells 5, the outer periphery of the electrolyte matrix 2 is sealed by contacting the edge seal portions 6a and 6b.
a flowing through the gas channels 8a are supplied to the anode 3 without leaking to the outside. Then, in the single cell 5, the hydrogen and the air generate power by an electrochemical reaction.

In the cooling section 11, gas channels 8a through which air flows face one side of the partition plate 10, and both sides thereof are sealed by contacting an edge seal section 6b. Gas channels 7a, through which hydrogen flows, face the other surface of the partition plate 10, and both sides of the gas channel 7a are sealed by contacting an edge seal portion 6a. Therefore, an air passage and a hydrogen passage are formed along the stacking surface of the partition plate 10.

FIG. 2 is a partially enlarged view of the cooling unit 11 and also shows the flow of hydrogen and air. Hydrogen flows in the gas channels 7a in the direction of the black arrow, and air flows in the gas channels 8a in the direction of the white arrow. The gas channels 7a ... and the gas channels 8a ... are both formed along the laminated surface of the composite separator 9, and both flow directions are orthogonal to each other. In the cooling unit 11, hydrogen and air flowing through the gas channels 7a and 8a are not used for the reaction but serve as a cooling medium.

In this way, the remaining air used for the reaction or cooling while flowing through each gas channel 8a is:
The gas is collected by the air collection manifold and the gas channel 7
The remaining hydrogen used for the reaction or cooling while flowing through a ... is recovered by a hydrogen recovery manifold. The high-temperature hydrogen recovered by the hydrogen recovery manifold may be discharged to the outside as it is, but a recycling pipe is provided from the hydrogen recovery manifold to the hydrogen supply manifold, and the hydrogen recovery manifold is used. The recovered hydrogen can be returned to the hydrogen supply manifold, mixed with hydrogen from the hydrogen supply source, and reused.

[Explanation of Effect of Fuel Cell 1] In the cooling section 11, since the directions of flow of air and hydrogen as cooling media are orthogonal to each other, the in-plane temperature distribution of the unit cell 5 is made uniform. . Further, hydrogen and air are used as a cooling medium in the cooling unit 11, and the thermal conductivity of the hydrogen gas is 18.2 × 10 ⁻⁴ W / (cm-deg), and the thermal conductivity of air is 2.6 × 10 ^-4 W / (cm-d
eg), which is about seven times larger than that in the case where only air is used as the cooling medium.

In the fuel cell 1, hydrogen and air as cooling media are supplied to the cooling section 11 from a hydrogen supply manifold for supplying hydrogen to the anode 3 and an air supply manifold for supplying air to the cathode 4. Therefore, there is no need to separately provide a supply source or a pipe for supplying a cooling medium to the cooling unit 11. In addition, when a pipe or the like for recycling hydrogen is provided, the utilization rate of hydrogen gas can be improved.

In the fuel cell 1, the cooling section 11 is constituted by interposing a flat partition plate 10 between the composite separators 9, so that a cooling plate having a passage for a cooling medium is separately manufactured. No need to do. Therefore, the cooling section 11 can be manufactured at low cost. Further, since the cooling unit 11 occupies a smaller volume than when using a cooling plate having a passage for a cooling medium, it also contributes to downsizing of the battery stack.

As shown in FIG. 2, a slight gap 7c is formed between the rib 7b and the partition plate 10, and a slight gap 8c is formed between the rib 8b and the partition plate 10. be able to. Therefore, the gas channel 7a
The hydrogen flowing through the gas channel 8a and the air flowing through the gas channel 8a also flow into the gaps 7c and 8c as shown by the thin arrows in the figure, so that heat exchange between hydrogen and the porous substrate 7 and air and the porous substrate 8, heat exchange is well performed, and a high cooling effect can be obtained.

(Embodiment 2) The fuel cell of this embodiment has the same configuration as the fuel cell 1 of Embodiment 1,
Gas channels 7a for hydrogen in the composite separator 9 ...
Are formed in directions perpendicular to each other in the fuel cell 1, whereas the gas channels 8 a for air are formed in parallel to each other in the fuel cell of the present embodiment. However, the difference is that the external manifold is mounted on the fuel cell, whereas the fuel cell of the present embodiment is provided with the internal manifold.

That is, in the composite separator of the present embodiment, the back side edge seal is provided along the one side edge seal of the separator plate so that the gas channels of the two porous substrates are parallel to each other. It is packed. In addition, a manifold hole for supplying / discharging hydrogen to a gas channel of one porous substrate and a manifold hole for supplying / discharging air to a gas channel of the other porous substrate are provided on an outer peripheral portion of the separator plate. And has been established.

The composite separator in which the gas channels for hydrogen and air are formed in parallel with each other and the inner manifold hole is provided in the outer peripheral portion has been conventionally used in a fuel cell. Detailed description is omitted. In the cooling section of the fuel cell according to the present embodiment, since hydrogen and air flow in opposition to each other, as described later, the uniformity of the in-plane temperature distribution of the unit cell is further improved as compared with the case of the first embodiment. Excellent effect to convert.

[2] Description of Cooling Effect of Cooling Unit In the fuel cells of the first and second embodiments, the cooling effect of the cooling unit on the unit cells will be described. For simplicity of description, here, it is assumed that each unit of the unit cell generates power uniformly and generates heat uniformly. First, as shown in the schematic diagram of FIG. 3, a description will be given of an operation of causing a cooling medium flowing in one direction through the cooling unit to generate a temperature gradient with respect to a unit cell adjacent to the cooling unit.

As this cooling medium flows from the inlet A to the outlet B, it receives heat from the cells and becomes high in temperature. Therefore, as shown by the length of arrows H1 to H4 in the drawing, the cooling medium has a higher cooling power than the inlet A. At the outlet B, the cooling power of the cooling medium (the amount of heat that the cooling medium takes from the unit cell) decreases. Therefore, the in-plane temperature of the cell gradually increases from the inlet A to the outlet B,
A temperature gradient occurs as shown by the hatched portion in the figure. This temperature gradient increases as the degree of reduction in the cooling power of the cooling medium from the inlet A to the outlet B increases.

The degree of decrease in the cooling power of the cooling medium is proportional to the temperature difference of the cooling medium between the inlet A and the outlet B,
It is considered that it is almost proportional to the flow rate of the cooling medium. next,
The relationship between the form in which the cooling medium flows through the cooling section and the in-plane temperature of the adjacent unit cell will be considered. 4 to 6 are schematic diagrams showing the relationship between the flow of the cooling medium in the cooling unit and the temperature distribution of adjacent cells.

FIG. 4 shows the case where the cooling medium flows in only one direction, FIG. 5 shows the case where the cooling medium flows in two directions orthogonal to each other, and FIG. 6 shows the case where the cooling medium flows in two directions facing each other. Shows the case. In any case, the cooling medium flows along the lamination surface of the cooling unit, the cooling medium is the same, and the total flow rate is also the same. As shown in FIG. 4, when the cooling medium is allowed to flow only in one direction (inlet A → outlet B) in the cooling section, the unit cell has inlet A → outlet B
A temperature gradient occurs in the direction.

As shown in FIG. 5, when the cooling medium is circulated in the cooling section in two directions (A → B and C → D) orthogonal to each other, the cell has a direction of either A → B or C → D. A temperature gradient also occurs, but the temperature gradient is smaller than in FIG. The reason why the temperature gradient is reduced is that the temperature difference of the cooling medium between the inlet A and the outlet B and the temperature difference of the cooling medium between the inlet C and the outlet D are the same as those in FIG.
This is because the flow rate of the cooling medium in each direction is smaller than that in the case of FIG. 4, and the degree of reduction in the cooling power of the cooling medium in each direction is smaller than that in the case of FIG.

As shown in FIG. 6, when the cooling medium is circulated in two opposite directions (inlet A → outlet B and inlet B → outlet A), as in the case of FIG. The degree of decrease in the cooling power is smaller than that in the case of FIG. Further, the action of the cooling medium in the direction from the inlet A to the outlet B to cause a temperature gradient in the cell, and the action of the cooling medium in the direction from the inlet B to the outlet A to cause the temperature gradient in the cell. And are offset. Here, entrance A → exit B and entrance B
→ If an equal amount of the cooling medium flows through the outlet A, the in-plane temperature of the unit cell can be made substantially uniform.

As described above, in the cooling section, when the cooling medium is circulated in two different directions along the lamination surface, the in-plane temperature of the adjacent unit cells is reduced as compared with the case where the cooling medium is circulated in one direction. The temperature can be made uniform. In particular, the effect of temperature uniformity is excellent if the cooling medium is circulated in two opposite directions. Here, although the unit cell adjacent to the cooling unit has been considered, the same can be said for a unit cell arranged away from the cooling unit.

Since the in-plane current density of the unit cell increases as the temperature increases, if the temperature variation within the unit cell is large, the local current becomes high and the unit cell is liable to deteriorate. If the in-plane temperature of the
Since the in-plane current density of the unit cell is also made uniform, a locally high current density does not occur. Accordingly, the life of the fuel cell is prolonged.

[0040]

【Example】

(Example 1) Based on the fuel cell 1 of the above embodiment,
A total of 30 cells 5 were stacked, and a fuel cell in which the cooling unit 11 was interposed every five cells was produced. The area of the anode 3 and the cathode 4 is about 200 cm 2, and the partition plate 10
A 0.4 mm thick plate made of glassy carbon was used.

The operating conditions were as follows: fuel efficiency of hydrogen gas: 80
%, Operating pressure: 1 ata (normal pressure), operating temperature: 120
° C, current density: 100 mA / cm2. (Example 2) Based on the fuel cell of Embodiment 2 described above,
A total of 30 cells were stacked, and a fuel cell with a cooling unit interposed every five cells was produced. The area of the anode 3 and the cathode 4 was about 200 cm 2, and the partition plate 10 was a 0.4 mm thick plate made of glassy carbon.

The operating conditions were set in the same manner as in Example 1. (Prior art example) The fuel cell of this conventional example has the same structure as the fuel cell of the first embodiment, except that the cooling unit 11 is not provided. The operation was performed under the same operation conditions as in Example 1, but
In the gas channel 8a for air of each composite separator 9,
A large amount of air was circulated for both supplying air to the cathode 4 and cooling.

For the fuel cells of Examples 1 and 2 and the conventional example, the in-plane temperature distribution of the unit cells 5 and the temperature difference in the stacking direction of the unit cells 5 were measured as follows. [Measurement of in-plane temperature distribution of unit cell] The in-plane temperature distribution of the unit cell 5 was measured with respect to the unit cells 5 adjacent to the cooling unit 11 for the fuel cells of Examples 1 and 2 and the conventional example. The measurement was performed by measuring the temperature of each part in the plane.

The temperature of each part of the cell 5 was measured by arranging a thermocouple in the air gas channel 8a adjacent to the cell 5 to be measured. The details of this measuring method are disclosed in Japanese Patent Application Laid-Open No. 5-76749. Note that the same measurement result can be obtained even if a thermocouple is arranged in the gas channel 7a for hydrogen. 7 to 9 are schematic diagrams showing the measurement results of the in-plane temperature distribution of the unit cell.
8 shows a measurement result of the conventional example, FIG. 8 shows a measurement result of the first embodiment, and FIG. 9 shows a measurement result of the second embodiment.

As can be seen from the figure, the temperature difference between the A side and the B side in the plane is about 30 ° C. in the conventional example, but about 20 ° C. in the first and second examples. It is getting smaller. Further, the variation in the temperature in the CD direction is smaller in the first and second embodiments than in the conventional example.

As described above, in the fuel cells of Examples 1 and 2, it is understood that the temperature distribution in the plane of the unit cell can be made uniform as compared with the conventional fuel cells. [Measurement of temperature difference in unit cell stacking direction] The temperature difference of unit cell 5 in stacking direction was measured as follows. In the fuel cell of the first embodiment, the numbers of the five unit cells 5 sandwiched between the pair of cooling units 11 near the center in the stacking direction are sequentially denoted by N.
o. 1 to No. 5 for the conventional fuel cell,
The numbers of the five consecutive cells 5 at the center in the stacking direction are numbered in order. 1 to No. It was set to 5.

The fuel cells of Example 1 and the prior art are described in 1 to No. 5 (the central part near the exit of the air passage,
The temperature at the location indicated by P in FIG. 9) was measured using a thermocouple. FIG. 10 is a characteristic diagram showing the measurement result of the temperature difference in the stacking direction of the unit cells. The temperature of the unit cell of No. 3 (that is, the unit cell farthest from the cooling unit in the first embodiment) is used as a reference. No. for It shows the temperatures of the cells 1 to 5.

As shown in FIG. The temperature difference from the cell No. 3 is about 5 in the conventional example.
In contrast, in Example 1, the value was as small as about 3 ° C. As described above, the first embodiment in which the cooling unit is inserted is different from the conventional fuel cell in which the cooling unit is not provided.
In this fuel cell, the temperature difference in the stacking direction of the unit cells is small.

This is because, in a stacked fuel cell, the temperature difference in the stacking direction is smaller in the stacking fuel cell system than in the cooling system with air supplied to the cathode without the cooling unit. It shows that it can be made smaller. [Other Matters] As described above, the present invention has been described based on the embodiments. However, it goes without saying that the contents of the present invention are not limited to the above embodiments, and the following are also included in the present invention. included.

In the above embodiment, hydrogen is used as the anode gas, but the same effect can be obtained by using a hydrogen-rich reformed gas. In the above embodiment, the cooling unit is supplied with hydrogen and air as the cooling medium from the hydrogen gas supply manifold and the air supply manifold, but the form of supplying the cooling medium to the cooling unit is not limited thereto.
For example, a pipe for supplying a cooling medium may be separately provided.

Further, in the above embodiment, an example has been described in which hydrogen gas and air are used as the cooling medium that passes in the two directions in the cooling unit, but both the cooling media that pass in the two directions are air. Or both may be hydrogen. Alternatively, another cooling medium may be used. Further, in the above embodiment, an example is shown in which a composite separator combining a separator plate and a porous substrate is used,
The same applies to the case where a separator plate having a gas channel cut on the surface is used.

In the above embodiment, the description has been given of the phosphoric acid type fuel cell. However, the present invention can be similarly applied to a fuel cell of a polymer electrolyte type, an alkaline type, a solid electrolyte type or the like.

[0053]

As described above, according to the present invention, in a fuel cell comprising a cell stack in which a unit cell and a separator are stacked and a cooling unit is inserted, at least one of the cooling units includes a cooling medium. A first passage through which
And the second passage through which the cooling medium flows in a different direction from the first passage, along the stacking surface,
The in-plane temperature distribution of the unit cell can be made uniform, thereby prolonging the life of the fuel cell and improving the power generation efficiency.

Further, such a cooling unit can be constituted only by inserting a gas-impermeable and conductive partition plate between the gas separation plates. In this case, it is necessary to manufacture a separate cooling plate. Thus, the cooling unit can be realized at low cost.

[Brief description of the drawings]

FIG. 1 is an assembly diagram showing a configuration of a phosphoric acid fuel cell according to Embodiment 1.

FIG. 2 is a partially enlarged view of a cooling unit 11 shown in FIG.

FIG. 3 is a schematic cross-sectional view for explaining a cooling effect by a cooling unit.

FIG. 4 is a schematic diagram showing a relationship between a flow of a cooling medium in a cooling unit and a temperature distribution of an adjacent unit cell.

FIG. 5 is a schematic diagram showing a relationship between a flow of a cooling medium in a cooling unit and a temperature distribution of an adjacent unit cell.

FIG. 6 is a schematic diagram showing a relationship between a cooling medium flowing in a cooling unit and a temperature distribution of an adjacent cell.

FIG. 7 is a schematic diagram showing a measurement result of an in-plane temperature distribution of a unit cell.

FIG. 8 is a schematic diagram showing a measurement result of an in-plane temperature distribution of a unit cell.

FIG. 9 is a schematic diagram showing a measurement result of an in-plane temperature distribution of a unit cell.

FIG. 10 is a characteristic diagram showing a measurement result of a temperature difference in a stacking direction of the unit cells.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fuel cell 2 Electrolyte matrix 3 Anode 4 Cathode 5 Single cell 6 Separator plate 7,8 Porous substrate 7a, 8a Gas channel 7b, 8b Rib 9 Composite separator 10 Partition plate 11 Cooling part

Claims (6)

[Claims] 1. A fuel cell comprising a cell stack in which unit cells each having an anode and a cathode disposed on an electrolyte layer and gas separation plates are alternately stacked, and one or more cooling units through which a cooling medium flows are interposed. In at least one of the cooling units, a first passage through which a cooling medium flows and a second passage through which a cooling medium flows in a direction different from the first passage are arranged along the lamination surface. A fuel cell, which is provided. 2. The fuel cell according to claim 1, wherein hydrogen gas is supplied to the first passage. 3. A gas is supplied to the first passage from an anode gas supply source that supplies an anode gas to the anode, and a cathode gas supply source that supplies a cathode gas to the cathode is supplied to the second passage. 3. The fuel cell according to claim 1, wherein a gas is supplied. 4. The fuel cell according to claim 3, further comprising gas recovery means for recovering the gas passing through the first passage and mixing the gas with the gas supplied from the anode gas supply source to the anode. . 5. The cooling unit is characterized in that a gas impermeable and conductive partition plate is interposed between two gas separation plates adjacent to each other in the stacking direction. The fuel cell according to claim 3, wherein 6. The fuel cell according to claim 5, wherein the partition plate is made of a material selected from the group consisting of glassy carbon, graphitized carbon, and a mixture thereof.