JPH06338339A - Feeding of electrolyte to fuel cell and device therefor - Google Patents

Abstract

PURPOSE:To quantitatively feed electrolyte in a fuel cell. CONSTITUTION:A device for feeding electrolyte to a fuel cell comprises a cell main body A, an electrolyte pooling tank 1 serving as a feeding source of electrolyte, and a quantitative tank 2 for quantifying the electrolyte. After the electrolyte pooled in the electrolyte pooling tank 1 is once quantified in the quantitative tank 2, the electrolyte is fed to a cell main body. Since there is no possibility that the electrolyte exceeding the capacity of the quantitative tank 2 is fed to the cell main body, while the feeding of the electrolyte is carried out quantitatively, the reliability of feeding work of the electrolyte is improved. Also, the performance of the cell can be stabilized and the life span of the cell can be extended.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for supplying an electrolyte to a fuel cell and an apparatus therefor, and more particularly, to supplying an electrolyte to a fuel cell quantitatively in a required amount. Law and its equipment.

[0002]

2. Description of the Related Art In a fuel cell, when the electrolyte plate is not impregnated with an appropriate amount of electrolyte, if the electrolytic mass is too large, excess electrolyte will enter the electrode and block the electrode reaction field, resulting in poor performance. If it is too small, on the contrary, there is a problem that the internal resistance of the cell is increased and the cell voltage is decreased, the sealing property of the electrolyte plate is deteriorated, and causes gas cross and gas leakage to the outside. It is also known that when the operating time of a battery is long, the electrolyte gradually decreases due to evaporation or corrosion of members, and the internal resistance increases, so that the battery voltage decreases. Therefore, when the fuel cell is continuously operated for a long period of time, it is necessary to replenish the electrolyte periodically.

However, in a fuel cell, since the operating temperature is high and the electrolyte itself is highly alkaline, its supply is quantitative by a conventional flow meter and pump used in a normal fluid device. It was practically impossible to do this because of problems such as corrosion. Several proposals have hitherto been made as means for solving the problem, for example, as an improved method for supplying an electrolyte from an electrolyte storage tank outside the battery to the battery main body, as disclosed in JP-A-61-214367. In addition, from the electrolyte storage tank outside the battery, the electrolyte return line on the outlet side of the battery body is closed with a frozen seal, and the electrolyte is supplied to the battery body using gas pressure, and then the line on the electrolyte return side is released. However, a method of returning excess electrolyte to a storage tank is known.

[0004]

The method disclosed in the above publication solves the problem of corrosion by using gas pressure as the means for transferring the electrolyte, or by using the frozen seal method as the means for closing the electrolyte, and supplying the electrolyte. Although it is considered to be effective as a method, no particular consideration is given to quantitatively supplying the electrolyte to the fuel cell body. Therefore, it was difficult to determine how much electrolyte was supplied into the battery, and it was difficult to control the amount of electrolytic mass supplied. Thereby, in the actual supply, the electrolytic mass becomes excessive, and the excess electrolyte enters the electrodes and the gas passages of the separator,
There is a possibility that the performance of the battery is deteriorated and the corrosion of the separator is increased.

Further, in the impregnation of the electrolyte substrate with the electrolyte at the time of assembling the fuel cell, particularly in the case of the internal impregnation method, the height of the cell stack changes due to the impregnation of the electrolyte substrate with the electrolyte during firing of the battery. Therefore, at this time, the battery is partially tightened, and there is a fear that uniform impregnation of the cell may be hindered. An object of the present invention is to obtain a method for supplying an electrolyte to a fuel cell and a device therefor, in which the disadvantages of the above-mentioned conventional method for supplying an electrolyte during impregnation and replenishment are eliminated, and more specifically, an electrolyte is provided. By surely quantifying the electrolytic mass supplied to the fuel cell main body when supplying the fuel, it is possible to prevent excess and deficiency of the electrolyte supply amount, facilitate the work at the time of impregnation, and prevent gas cross leak and the like. An object of the present invention is to obtain a method and an apparatus for supplying an electrolyte to a fuel cell, which can stabilize the performance.

[0006]

As a basic means, the above object is to provide a fixed quantity tank capable of measuring a predetermined amount between the electrolyte storage tank and the battery main body, and use the pressure of the inert gas to store the electrolyte. This is achieved by separating the required amount of the electrolyte in the tank into a fixed quantity tank and then supplying the separated electrolyte to the battery main body, preferably using the pressure of an inert gas. This makes it possible to reliably control the electrolytic mass supplied to the battery body.

[0007]

According to the present invention, as shown in FIG. 1, between the electrolyte storage tank 1 and the fuel cell main body, there is provided a fixed quantity tank 2 which can measure a fixed quantity of the electrolyte, and the pressure of the inert gas is reduced. Thus, the electrolyte in the electrolyte storage tank 1 is sent to the fixed quantity tank 2. The quantification in the quantification tank 2 is preferably carried out by an overflow pipe or by an electric level gauge. This quantified electrolyte is supplied from the metering tank 2 to the fuel cell main body when necessary, preferably by the pressure of an inert gas. Thereby, the electrolytic mass supplied to the fuel cell main body can be reliably controlled.

In an ordinary chemical injection pump or the like, the transfer and measurement of the injection liquid are performed simultaneously by the operation of the pump. For the reasons mentioned above, such pumps cannot be used for electrolyte transfer and metering. In the present invention,
Transfer of the electrolyte by providing a quantitative tank between the supply source and the supply destination, that is, between the electrolyte storage tank and the fuel cell body, and transferring the electrolyte by another means, preferably by gas pressure transfer means. And weighing are configured to be separated into two stages.

That is, in a preferred embodiment of the present invention, the electrolyte transfer by means of gas pressure is employed as a means for transferring the electrolyte, which is reliable in operation but difficult to quantify, and is used for measuring (quantifying) the electrolyte. Adopts a preparative method in which the liquid level is controlled by an overflow pipe that has a simple structure and operates reliably. By combining these transfer and quantification means and quantifying the electrolyte and then supplying it to the fuel cell main body, it became possible to supply the electrolyte with high reliability and reliability during operation.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for supplying an electrolyte to a fuel cell and an apparatus therefor according to the present invention will be described below with reference to FIG. The illustrated apparatus has a fuel cell main body A and an electrolyte storage tank 1, and a metering tank 2 is provided between the fuel cell main body A and the electrolyte storage tank 1. A pipe 11 having one end opened near the bottom surface of the electrolyte storage tank 1 extends from the electrolyte storage tank 1 and has the other end opened above the metering tank 2. A frozen port 6 to be described later is formed in the middle of the pipe 11, and a thermocouple (not shown) is arranged in the frozen port 6 to confirm the open / closed state of the frozen port 6. In addition, the electrolyte storage tank 1 is a conventionally known conventional one.

The metering tank 2 is provided with an overflow pipe 14 for keeping the liquid level of the supplied electrolyte constant.
The other end of the overflow pipe 14 is the overflow pipe 1.
It is opened to an overflow tank 3 for receiving the electrolyte flowing out of the tank 4. The overflow tank 3 is physically located above the electrolyte storage tank 1.
The bottom of the overflow tank 3 and the electrolyte storage tank 1 are connected by a pipe 13, and the pipe 13 is also formed with a frozen port 7 having a thermocouple (not shown) like the pipe 11. Furthermore, overflow tank 3
From the upper gas phase region of the pipe, the pipe 10 is again provided with the electrolyte storage tank 1.
The pipes 9 respectively extend from the upper gas phase region, and the three-way valves 4 and 5 are attached to the pipes 10 and 9 in the middle thereof. The pipes 10 and 9 merge at the tip thereof to form a pipe 15, and the branch pipe 15 is connected to a high pressure carbon dioxide cylinder B as a gas pressure source via a pressure reducing valve 8.

In the present invention, as the fuel cell main body, an ordinary one is used except for an electrolyte supply system from the outside. FIG. 3 shows an example of an external electrolyte supply system suitable for use in the fuel cell of the present invention. That is, the separator 1
In an ordinary single cell composed of 6, an electrolyte plate 17, an anode 18, a cathode 19, etc., an electrolyte receiving port 16a is provided in a part of the separator 16. Further, a dispenser 15 is located near the electrolyte receiving port 16a, and the open end of the pipe 12, which is the electrolyte supply line, is located on the dispenser 15. As a result, the electrolyte sent from the pipe 12 is distributed to each cell via the dispenser 15.

The fixed quantity tank 2, the overflow tank 3, the overflow pipe 14, and the pipes are made of a material which is in direct contact with the electrolyte and is made of a material which is heat resistant and is not easily corroded by the electrolyte, preferably a stainless material. Apply aluminum coating on the inner surface. Further, the valves are similarly made of a member having heat resistance and corrosion resistance, preferably ceramics.

Next, the above-mentioned frozen port will be described. The frozen port functions as a kind of valve by solidifying or melting the electrolyte by cooling and heating a part of a pipe through which the electrolyte flows, and a conventionally known mode is appropriately used. For example, when the electrolyte is molten carbonate (melting temperature 491 ° C),
By cooling a part of the pipe with air or N ₂ gas, the electrolyte can be easily solidified at the cooled part. The open / closed state is confirmed by means such as temperature measurement using a thermocouple. In the following description, a state in which cooling air is supplied to the frozen port to solidify the electrolyte is referred to as a closed frozen port, and a state in which the supply of the cooling air is stopped to melt the electrolyte and cause the electrolyte to flow is referred to as a frozen port open.

The mode of use of the above apparatus will be described with reference to FIG. First, the electrolyte storage tank 1 is filled with an electrolyte in advance, and the electrolyte storage tank 1 is arranged in a region near the fuel cell main body near the cell operating temperature. It is preferable that the filling amount of the electrolyte is such that a certain amount of allowance is provided so that the liquid level of the electrolyte is higher than the open end position of the pipe 11 which is the electrolyte supply line even after the completion of the electrolyte supply described later.

The electrolyte storage tank 1 is filled with the electrolyte as follows.・ Procedure (1) Store a small amount of electrolyte in the frozen ports 6 and 7 in advance. -Procedure (2) With the three-way valve 5 of the pipe 9 communicating, the three-way valve 4 of the pipe 10 open to the outside, the frozen port 6 of the pipe 11 open, and the frozen port 7 of the pipe 13 closed, the pressure reducing valve of the pipe 15 8 is adjusted, high-pressure carbon dioxide is supplied to the electrolyte storage tank 1 through the pipe 15 and the pipe 9, and the inside of the tank 1 is pressurized. The electrolyte moves to the metering tank 2 through the pipe 11 by the gas pressure. At this time, the gas pressure applied to the fixed quantity tank 2 is discharged to the outside through the overflow pipe 14 and the pipe 10, and from the three-way valve 4 at the open position. When the liquid level of the electrolyte supplied to the metering tank 2 reaches the position of the overflow pipe 14, the electrolyte flows into the overflow pipe 1.
It flows into the overflow tank 3 through 4 and temporarily accumulates there. That is, a certain amount of the electrolyte is taken in the fixed quantity tank 2. -Procedure (3) Closing frozen port 7 of piping 13, closing frozen port 6 of piping 11, closing valve 5 of piping 9, and piping 10 valve 4
In the communication state, high-pressure carbon dioxide gas is supplied into the quantitative tank 2 through the pipe 10, the overflow tank 3, and the overflow pipe 14 to pressurize the quantitative tank 2. As a result, the electrolyte collected in the fixed quantity tank 2 is supplied to the fuel cell main body through the pipe 12 which is an electrolyte supply line.

The state of receiving the electrolyte on the fuel cell side at this time will be described. The electrolyte pumped by the pipe 12 that is an electrolyte supply line is placed in the dispenser 1 adjacent to the fuel cell body.
It is released within 5. At this time, since the dispenser 15 is in an open state, the pressure of the electrolyte is once released. The electrolyte that has entered the dispenser 15 is dropped and distributed by the dispenser 15 to the electrolyte receiving port 16a provided in each cell of the fuel cell.

According to the above procedure, the electrolyte in the electrolyte storage tank 1 is once sorted into the fixed amount tank 2 and then supplied to each cell of the fuel cell main body. At this time, the total electrolyte supplied to the fuel cell main body. The amount is the total volume between the lower end position of the pipe 12 and the mounting position of the overflow pipe 14 in the fixed quantity tank 2. By setting this volume in advance to a value obtained by dividing the required amount by an integer, it is possible to quantitatively supply or impregnate the electrolyte by repeating this operation as many times as necessary.

When the electrolyte overflowing from the quantitative tank 2 is accumulated in the overflow tank 3 to some extent, it must be returned to the electrolyte storage tank 1. The operation at this time is shown below. -Procedure (1) The pipe 13 is left open with the frozen port 7 open, the pipe 11 with the frozen port 6 open, the pipe 9 with the valve 5 open to the outside, and the pipe 10 with the valve 4 open to the outside. At this time, the electrolyte accumulated at the bottom of the overflow tank 3 is returned to the electrolyte storage tank 1 through the pipe 13 which is an electrolyte return line.

As is clear from the above description, in the above operation, the supply of the electrolyte to the fuel cell body and the return of the electrolyte from the overflow tank to the electrolyte storage tank can be performed at the operating temperature of the fuel cell. Therefore, it is not necessary to lower the temperature of the fuel cell for that purpose, and continuous operation of the fuel cell becomes possible. In the actual supply of the electrolyte in the fuel cell, it may be desirable to change the supplied electrolytic mass depending on the purpose. For example, the following two cases can be considered as typical cases in which the supply of the electrolyte in the fuel cell is required.

(1) Impregnation of Electrolyte Substrate with Electrolyte This is the first supply of the electrolyte to the electrolyte substrate during fuel cell assembly, that is, impregnation, and this is the largest amount to be supplied. At this time, the required mass of electrolysis is usually about 1500 cc for a kw class fuel cell. (2) Impregnation of electrolyte during fuel cell operation This is a case where electrolyte is gradually replenished during fuel cell operation due to evaporation and corrosion of members, and so on. Normally, the replenishment amount at this time is about 5% of the total pore volume of the electrolyte plate, which is about 120% in the kw class fuel cell.
It is about cc.

As described above, the impregnated amount of the electrolyte is considerably different in each case. The second aspect of the present invention is for coping with such a different aspect, and preferably a plurality of tanks having different capacities are prepared in advance as the metering tanks, and the tanks used for supply are supplied as needed. By switching, the work such as lowering the temperature of the fuel cell body and replacing the capacity tank is omitted, and the electrolyte can be easily supplied in all cases.

For example, as shown in FIG. 4, two fixed quantity tanks 2a and 2b having different capacities are arranged in parallel between the fuel cell body and the electrolyte storage tank 1. When the fixed quantity tank 2a has a capacity of 100 cc and the tank 2b has a capacity of 60 cc, and 1500 cc of electrolyte is required for electrolyte impregnation, it is sufficient to supply the above cycle 15 times with the 100 cc fixed quantity tank 2a. If 60cc is required for electrolyte replenishment at the time, fixed quantity tank 2
It is sufficient to supply twice in b. In this way, by preparing tanks of different capacities in advance, the electrolyte can be supplied from the impregnation of the electrolyte to the time of replenishment without lowering the temperature of the fuel cell.

Next, the timing of electrolyte replenishment will be described below with reference to FIG. The vertical axis represents the battery voltage and the horizontal axis represents the operating time. A line 24 shows a change in the fuel cell voltage when the electrolyte is not replenished, and a line 23 shows a change in the fuel cell voltage when the electrolyte is replenished periodically.
Points 26a and 26b indicate points for electrolyte replenishment, and a broken line 25 is a 1% drop line of the battery voltage, which is a standard for replenishment, from the initial battery voltage.

When the fuel cell is continuously operated, the voltage of the fuel cell gradually decreases as time passes, as shown by the line 24. It is known that the main cause of such a battery voltage drop is the increase in the internal resistance of the cell due to the consumption of the electrolyte due to the evaporation of the electrolyte in the electrolyte plate and the corrosion of the battery members. Therefore, at the time point 26a where the amount of decrease in the battery voltage approaches the 1% drop line, the battery voltage is restored as shown in the figure by performing the above electrolyte replenishment. After the replenishment is completed, continuous operation is continued, and the voltage drop again approaches the 1% drop line. Point 26b
To replenish the electrolyte and recover the battery voltage. By repeating the continuous operation, the drop of the cell voltage, the replenishment of the electrolyte, and the recovery of the cell voltage in this manner, the life of the fuel cell can be significantly extended as compared with the case where the electrolyte is not replenished.

The above example is a form in which one electrolyte supply device is provided in one battery stack, but the present invention is not limited to this mode, and one supply device is configured to be shared by a plurality of stacks. It is also possible to do so. An example will be described. FIG. 7 shows an example thereof, and the electrolyte supply device 5
Reference numeral 0 indicates a device portion for supplying an electrolyte to the fuel cell main body in the device described above with reference to FIG. In this embodiment, a pipe 51 corresponding to an electrolyte supply line has a line switching valve 52 at its tip, and a plurality of pipes 55 ... Extend from the valve 51 and the tip thereof is connected to a battery stack 60, respectively. is doing. Frozen ports 53 ... Are formed in the middle of the pipes 55.

In using this device, first, the switching valve 52 is operated to connect the pipe 55 for connecting to the battery stack that needs to be impregnated or replenished with the electrolyte and the pipe 51 on the electrolyte supply device side, and then The normally closed frozen port 53 is opened. In that state, the electrolyte supply device 5
0 is operated to fractionate the electrolyte in the metering tank and transfer the fractionated electrolyte to the battery stack. If necessary, the switching valve 52 is operated to repeat the supply to other battery stacks. After the required supply is completed, the phrased port is closed to complete the work.

The above description is only a description of some embodiments of the method for supplying an electrolyte to a fuel cell and its apparatus according to the present invention, and many other variations exist. For example, in the above description, the overflow pipe 1 is used as the measuring method in the metering tank 2.
Although the measurement method using 4 has been described, it is also effective to use the electric conductivity of the electrolyte as another measurement method. An example of the quantitative tank at this time is shown in FIG. Two electrodes 20 and 21 are inserted in the metering tank 2. From the viewpoint of corrosion resistance, it is preferable to use a noble metal such as gold for the portion of the electrode 20 that comes into contact with the electrolyte. Further, the electrode 21 can be converted into the volume of the electrolyte on each scale in advance by embedding a plurality of gold wires in a rod of alumina ceramics having excellent corrosion resistance to the electrolyte and exposing the tips at equal intervals on the surface of the alumina. Keep it like this. These lines are installed in parallel between the series of resistors 22 having appropriate resistance values as shown. When the resistance between the resistance measurement terminals is measured after wiring in this way, the terminals immersed in the electrolyte are short-circuited as the liquid level in the metering tank rises, so that the resistance value at the resistance measurement terminals changes. It is possible to know the change of the liquid surface by utilizing this fact.

The object of the present invention can also be achieved by supplying the electrolyte to the fuel cell main body after quantifying the electrolyte using such a metering tank. In this case, a plurality of different quantifications can be carried out by one quantification tank, so that it is possible to achieve the same operation as the case where a plurality of quantification tanks shown in FIG. Become. Further, it will be easily understood that in this case, the member corresponding to the overflow tank shown in the previous embodiment is not necessarily essential.

Further, in the present invention, since gas pressure is mainly used as the means for transferring the electrolyte, it is desirable that the electrolyte storage tank and the fixed quantity tank have a sealed structure. However, from the aspect of electrolyte filling and maintenance, the O-ring is used. It is highly desirable to have a structure that can be disassembled by a flange that uses a sealing material such as. Regarding the electrolyte supply pipe, it is recommended to reduce the inner diameter of the pipe to about 1 to 2 mm in order to minimize the error in the supply amount due to the electrolyte pipe volume. However, the electrolyte flowing in the pipe is highly alkaline at high temperature and is highly corrosive. Therefore, when the pipe diameter is reduced, the pipe may be corroded and clogged. As a countermeasure against this, by coating the inside of the pipe and the tank with aluminum to improve the corrosion resistance to the electrolyte, it is possible to prevent clogging of the pipe and the like due to corrosion.

Further, although the description has been given of the case where the frozen port is used as the valve of the electrolyte flow path, a mechanical valve mechanism which can be surely operated remotely at a high temperature and whose electrolyte contact portion is made of a material excellent in electrolyte resistance. It is also possible to use (for example, a valve mechanism using alumina-based ceramics for its movable part and liquid contact part) instead of the frozen port.

Further, positioning the electrolyte storage tank 1 near the temperature of the fuel cell main body is a very preferable mode because the temperature of the electrolyte to be supplied can be brought close to the temperature of the fuel cell main body in advance. When the heating means such as a heater is separately provided in the overflow tank and the like, the electrolyte storage tank 1 can be arranged at a position somewhat separated from the fuel cell main body, and at that time, maintenance of the electrolyte supply system is performed. Will be even easier.

In the above embodiment, the gas pressure is used both as the means for transferring the electrolyte from the electrolyte storage tank to the metering tank and from the metering tank to the fuel cell body. However, in the present invention, the electrolyte storage is used. It is essential to use gas pressure as a transfer means from the electrolyte storage tank to the metering tank so that the electrolyte in the tank can be reliably measured (quantified) in the metering tank. It will be readily appreciated that the transfer means may be replaced by other supply means, including drop by gravity, instead of gas pressure. If a drop due to its own weight is used as the transfer means, place a quantitative tank at a position physically higher than the fuel cell body, and use a valve function such as the above-mentioned frozen port in the pipe connecting them. Try to intervene the means to have.

[0034]

EFFECTS OF THE INVENTION According to the present invention, the amount of electrolyte supplied can be quantitatively controlled, and excessive impregnation and lack of electrolyte can be prevented. Further, the electrolyte can be supplied even during the operation of the fuel cell, and the electrolyte can be supplied according to the degree of lack of the electrolytic mass.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic configuration of an electrolyte supply device according to the present invention.

FIG. 2 is a diagram showing an embodiment of an electrolyte supply device according to the present invention.

FIG. 3 is a view showing an electrolyte receiving structure on the fuel cell main body side.

FIG. 4 is a diagram showing a configuration of a plurality of fixed quantity tanks.

FIG. 5 is a view showing another embodiment of the metering tank.

FIG. 6 is a diagram illustrating a fuel cell operating time and a timing at the time of electrolyte replenishment.

FIG. 7 is a diagram showing another embodiment of the electrolyte supply device according to the present invention.

[Explanation of symbols]

1 ... Electrolyte storage tank, 2 ... Fixed quantity tank, 3 ... Overflow tank, 4.5 ... Three-way valve, 6.7 ... Frozen port, 8 ... Pressure reducing valve, 9.10.11.12.1
3.14.15 ... Piping, A ... Fuel cell body, B ... Gas cylinder

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tsutomu Takahashi 3-1-1, Saiwaicho, Hitachi-shi, Ibaraki Hitachi Ltd. Hitachi factory

Claims (8)

[Claims] 1. In a method of supplying an electrolyte for a fuel cell, a metering tank capable of measuring a predetermined amount is provided between an electrolyte storage tank and a cell body, and an electrolyte in the electrolyte storage tank is charged by utilizing a pressure of an inert gas. A method for supplying an electrolyte to a fuel cell, which comprises collecting the required amount in a fixed quantity tank and then supplying the separated electrolyte to the cell body. 2. A fixed quantity tank capable of measuring a predetermined amount is provided between the fuel cell body and the electrolyte storage tank, and means for transferring the electrolyte in the electrolyte storage tank to the fixed quantity tank and the electrolyte in the fixed quantity tank are used as fuel. An apparatus for supplying an electrolyte to a fuel cell, comprising: a means for transferring to the cell body. 3. The electrolyte supply device for a fuel cell according to claim 2, wherein the metering tank has an overflow pipe as a means for measuring the amount of electrolyte. 4. The electrolyte supply device for a fuel cell according to claim 2, wherein the metering tank has means for electrically detecting the liquid level of the electrolyte as means for measuring the electrolyte. 5. A means for transferring the electrolyte in the electrolyte storage tank to the metering tank and a means for transferring the electrolyte in the metering tank to the fuel cell main body, further comprising an inert gas tank. The electrolyte supply device for a fuel cell according to claim 2, wherein 6. A frozen port is formed in the pipe between the electrolyte storage tank and the metering tank, the frozen port having a function of enabling or blocking the movement of the electrolyte by melting or solidifying the electrolyte. The electrolyte supply device for a fuel cell according to claim 2. 7. The electrolyte supply device for a fuel cell according to claim 2, wherein a ceramic valve is provided as a valve member in the pipe between the electrolyte storage tank and the fixed amount tank. 8. The electrolyte supply device for a fuel cell according to claim 2, wherein the fixed quantity tank comprises a plurality of tanks having different capacities.