JP3249282B2 - Solid polymer electrolyte fuel cell - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a method (humidification method) of simultaneously supplying gas and moisture to a power generator using a polymer electrolyte which exhibits its performance by containing water, that is, an electrochemical cell (hereinafter also referred to as a cell). Fuel cell.

[0002]

2. Description of the Related Art In a fuel cell using a solid polymer membrane such as Nafion of DuPont, it is necessary to include sufficient moisture in the solid polymer in order for the solid polymer membrane to exhibit ionic conductivity as an electrolyte. . Conventionally, a humidifying container (a humidifier container) is prepared as shown in FIG.
Among them, a method has been adopted in which a fuel gas and an oxidizing gas are passed through warm water and the gas contains water vapor (hereinafter referred to as a humidifier method).

[0003]

The conventional humidifier type fuel cell requires a large humidifier container (humidifier container), and is not suitable for a fuel cell pursuing compactness. Further, in order to control the amount of moisture for humidification, a heater for controlling the temperature of the humidification water to increase the temperature was required. Therefore, there has been a problem that the efficiency of the fuel cell system is reduced by the heater power. An object of the present invention is to provide a fuel cell capable of humidifying a solid polymer membrane of a fuel cell without requiring the humidification container or heater power at all.

[0004]

(First Means) A solid polymer electrolyte fuel cell according to the present invention comprises a fuel cell power generator (cell) 8 having both sides of a solid polymer electrolyte sandwiched between two electrodes. In a solid polymer electrolyte fuel cell having a stack 4 of separators 1 for supplying gas to the power generator, the separator 1 has a plurality of fuel gas supply grooves 22 formed on one surface and a plurality of fuel gas supply grooves 22 formed on the other surface. A plurality of oxidizing gas supply grooves, a humidification water supply header 25 formed therein for fuel gas humidification, and a humidification water supply groove formed inside so as to communicate with the humidification water supply header. A humidification water injection pipe 26 for fuel gas humidification for supplying water;
A humidifying water supply header formed therein for oxidizing gas humidification, and an oxidizing gas humidifying humidifying water supply header formed therein so as to communicate with the humidifying water supply header and supplying humidifying water to the oxidizing gas supply groove. A humidification water injection pipe, and in the fuel gas supply groove 22 and the oxidizing gas supply groove 33 of the separator,
By adding water to the gas, a mixed flow of the gas and the water is created, and the gas and the water are simultaneously supplied to the fuel cell power generator. (Second Means) A solid polymer electrolyte fuel cell according to the present invention comprises a fuel cell power generator (cell) having two electrodes sandwiched on both sides of a solid polymer electrolyte, and a separator 1 for supplying gas to the power generator. In the solid polymer electrolyte fuel cell having, the separator, a plurality of fuel gas supply grooves formed on one surface,
Humidification water supply header 2 formed inside for humidification of fuel gas
5 and a humidification water injection pipe 26 formed therein so as to communicate with the humidification water supply header and supplying humidification water to the fuel gas supply groove 22. In the fuel gas supply groove 22 of the separator, By adding water to the fuel gas, a mixed flow of the fuel gas and water is formed, and the fuel gas and the water are simultaneously supplied to the fuel cell power generator. (Third Means) A solid polymer electrolyte fuel cell according to the present invention comprises a fuel cell power generator (cell) having two electrodes sandwiched on both sides of a solid polymer electrolyte, and a separator 1 for supplying gas to the power generator. The separator 1 includes a plurality of oxidizing gas supply grooves 33 formed on one surface, a humidifying water supply header formed therein for oxidizing gas humidification, A humidifying water supply pipe formed to communicate with the humidifying water supply header and supplying humidifying water to the oxidizing gas supply groove 33; By adding water to the gas, a mixed flow of the oxidizing gas and water is formed, and the oxidizing gas and water are simultaneously supplied to the fuel cell power generator.

(Fourth Means) In the solid polymer electrolyte fuel cell according to the present invention, the first means, the second means or the third means is characterized in that the gas is supplied to the humidified water inlet of the gas supply groove. It is characterized in that the supply groove is made thin.

[0006]

The fuel cell according to the present invention has a structure in which gas and water are mixed in the fuel cell stack 4 and then supplied to a power generator (cell) of the fuel cell. Therefore, an inlet for water is provided so that water can be directly dropped into the gas supply groove of the separator. That is, the gas (fuel gas, oxidizing gas) supplied to the stack 4 in which the separator 1 and the cell 8 are stacked flows into the gas supply groove of the separator 1 via the header section (or the manifold section). Then, the water droplets and the gas supplied from the humidification water inlet in the gas supply groove are mixed and humidified to reach the power generator (cell).

[0007]

FIG. 1 shows a first embodiment of the present invention and FIG. 2 shows a second embodiment of the present invention. First Embodiment FIG. 1 shows a cross-flow bipolar separator (fuel flows on one side of the separator and oxidant flows on the other side, and one side of the separator becomes an anode and the other side becomes a cathode. This is an example in which an inlet for humidification is provided in the case where the flow is orthogonal.

The humidifying water for fuel gas is supplied from the humidifying water supply header inlet 24 through the humidifying water supply header 25 and the humidifying water injection pipe 26 to the humidifying water injection port 27 into the fuel gas supply groove 22. Then, the fuel gas and the humidifying water are mixed and further flow through the fuel gas supply groove 22 to be supplied to the cell 8.
The oxidizing gas is also supplied while being mixed with the humidifying water. That is, the solid polymer electrolyte fuel cell of the present invention has a structure in which gas and water are mixed in the fuel cell stack 4 and the humidified gas is supplied to the power generator (cell). Therefore, the cross-flow type bipolar separator (hereinafter, referred to as a separator or a bipolar separator) 1 shown in FIG. 1 is used as the separator.

In the bipolar separator 1 used in the present invention, as shown in FIG. 1, a fuel gas flows from a fuel gas supply groove 22 on one surface (hereinafter referred to as a fuel gas inflow surface) of the bipolar separator 1 and an oxidant. The gas flows from the oxidizing gas supply groove 33 on a surface adjacent to the fuel gas inflow surface (hereinafter referred to as an oxidizing gas inflow surface), and the direction of the fuel gas flow 21 and the direction of the oxidizing gas flow 31 are orthogonal to each other. One surface of the separator 1 is an anode and the surface adjacent to the surface is a cathode.

[Second Embodiment] FIG. 2 is an enlarged sectional view of a humidification water injection pipe 26 and a humidification water injection port 27 of a second embodiment. In the second embodiment, the separator of the first embodiment is modified as follows. That is, as shown in FIG. 2, the gas supply groove is made thinner at the humidification water inlet of the gas supply groove. In this case, the supply and mixing of the humidifying water are performed smoothly.
In FIG. 2, the groove is made thinner by changing the depth of the gas supply groove 22. However, the groove may be made thinner by changing the groove width. Also, the groove may be narrowed by both.

Although power can be generated by mixing the humidified water and the gas in the gas supply groove as in the first embodiment, the second embodiment can be used.
By examining the groove shape of the humidification water inlet and the diameter (not shown) of the humidification water injection pipe as shown in the figure, the output equivalent to the power generation performance when using a humidification container is also obtained. Voltage can be obtained.

[0012]

Since the present invention is configured as described above, it has the following effects. (1) Since humidification is performed in the stack 4, a humidifier is not required, and the size is reduced. (2) Since water is directly supplied to the cell, the control of the amount of humidified water is easy, and at the same time, no heater power is required, and the efficiency of the system can be increased. (3) Since the heat generated on the power generation surface when the injected humidified water turns into steam is absorbed, the circulation amount of the cooling refrigerant can be reduced as compared with the conventional case. (4) Therefore, the efficiency can be improved by reducing the pump power, and the compactness can be improved by making the refrigerant pipe narrower.

[Brief description of the drawings]

FIG. 1 is a view showing a separator according to a first embodiment of the present invention.

FIG. 2 is a view showing a separator according to a second embodiment of the present invention.

FIG. 3 is a view showing a humidification method of a conventional apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Separator, 4 ... Stack, 8 ... Power generator (cell), 9 ... Electrode, 10 ... Electrolyte, 11 ... Sealing material, 12 ... Humidifier container (humidifier container), 13 ... Heater, 14 ... Stack, 21 ... fuel gas flow, 22 ... fuel gas supply groove, 24 ... humidification water supply header inlet (for fuel gas humidification), 25 ... humidification water supply header (for fuel gas humidification), 26 ... humidification water injection pipe (fuel gas humidification) 27) Humidifying water inlet (for fuel gas humidification), 31 ... Oxidizing gas flow, 33 ... Oxidizing gas supply groove, 35 ... Humidifying water supply header inlet (for oxidizing gas humidification)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-41230 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01M 8/04 H01M 8/02 H01M 8 / Ten

Claims (4)

(57) [Claims] 1. A solid polymer electrolyte fuel cell having a stack composed of a fuel cell power generator in which both sides of a solid polymer electrolyte are sandwiched between two electrodes and a separator for supplying gas to the power generator, wherein the separator comprises: A plurality of fuel gas supply grooves formed on one surface, a plurality of oxidant gas supply grooves formed on the other surface, a humidification water supply header for fuel gas humidification formed inside; A humidification water supply pipe for humidification of fuel gas formed to communicate with the humidification water supply header and supplying humidification water to the fuel gas supply groove, and a humidification water supply header for oxidizing gas humidification formed inside; A humidifying water injection pipe for humidifying gas humidification formed therein so as to communicate with the humidifying water supply header and supplying humidifying water to the oxidizing gas supply groove. Fuel gas supply groove and Adding water to the gas in the agent gas supply groove to form a mixed flow of the gas and water, and simultaneously supplying the gas and water to the fuel cell power generator. Molecular electrolyte fuel cell. 2. Two electrodes on both sides of a solid polymer electrolyte
A fuel cell power generator sandwiched there between and a cell for supplying gas to the power generator.
In a solid polymer electrolyte fuel cell having a parator, the separator includes a plurality of fuel gas formed on one surface.
Gas supply groove and humidification water formed inside for humidification of fuel gas
It communicates with the supply header and the humidification water supply header inside.
To supply humidified water to the fuel gas supply groove.
A humidified water injection pipe is provided, and by adding water to the fuel gas in the fuel gas supply groove of the separator, a mixed flow of the fuel gas and water is formed, and the fuel gas and water are supplied to the fuel cell power generator. And a solid polymer electrolyte fuel cell. 3. Two electrodes on both sides of a solid polymer electrolyte
A fuel cell power generator sandwiched there between and a cell for supplying gas to the power generator.
In a solid polymer electrolyte fuel cell having a parator, the separator has a plurality of oxidizing agents formed on one surface.
A gas supply groove and a humidifier
And Shimemizu supply header, through communication with the inside the pressurized Shimemizu supply header
Humidified water is supplied to the oxidizing gas supply groove.
Comprising a humidification water injection tube sheet, in the oxidizing gas supplying grooves of the separator by adding moisture to oxidizer gas, creating a mixed flow of the oxidant gas and water, the fuel cell power generator A solid polymer electrolyte fuel cell characterized by simultaneously supplying an oxidizing gas and water to a fuel cell. 4. The gas supply groove at the humidification water inlet portion of the gas supply groove is made thin.
4. The solid polymer electrolyte fuel cell according to any of 2 or 3.