JPS588109B2 - Nenryyou Denchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention utilizes the buoyancy of the electrolyte and the surface tension of the electrolyte caused by the gas generated when a gas is generated by a discharge reaction, such as hydrazine or formalin, in a fuel cell. This system automatically drains the electrolyte from inside the cell into the fuel electrolyte tank, and circulates the electrolyte between the fuel cell and the fuel electrolyte mixing tank according to the discharge flow. The purpose of the present invention is to provide a fuel cell that does not require a pump or its power and can provide stable power for a long period of time.

Generally speaking, fuel cells require the circulation of an electrolyte or electrolyte containing fuel in order to supply fuel, stabilize cell temperature, remove reaction products, etc. Since the beginning of development, most fuel cells have A portion of the generated electricity was used to operate a circulation pump to achieve this purpose.

However, circulation pumps have major disadvantages in that power generation must be frequently stopped for maintenance and a portion of the output of the fuel cell must be used.

Therefore, several methods have been proposed that do not require maintenance and can achieve the above-mentioned circulation without using part of the output.
One of them, Japanese Patent Publication No. 39-30349, “
In fuel cells that use substances that generate gas through reaction, the method of refluxing the fuel after the reaction to a storage device using the pressure of the gas generated through reaction was a revolutionary method.

However, since this method uses the pressure of the gas generated, the electrolyte is supplied to the battery by connecting two or more cells in series, and the supply piping from the fuel electrolyte storage device is connected to the first battery. The electrolyte supplied from the bottom of the tank is discharged from the top, and piping is arranged so that it flows downward.
Reflux could not occur unless it was supplied from the bottom of the second battery.

In other words, the downward piping connecting the first and second batteries is used as a tank, and the electrolyte is pumped under the pressure of the gas generated.
The reflux is based on the same principle as when a liquid placed in a U-shaped tube is pushed out to one side by applying downward gas pressure from one side, and in addition, the pressure of the electrolyte plus gas pressure is applied to the electrode. .

In general, gas electrodes have poor performance due to electrolyte wetting the active part of the electrode, so reflux is not desirable.

However, in this method, gas-generating substances are mixed with the electrolyte and gas is generated within the battery, but the gas-generating reaction within the battery occurs independently of the fuel cell's discharge reaction. However, it was not possible to circulate the electrolytic solution according to the discharge flow.

Furthermore, since a gas generating substance is used to circulate the electrolyte, it does not contribute to energy savings.

On the other hand, the device of the present invention uses the buoyancy of the electrolyte generated by the gas generated by the discharge reaction and the surface tension of the electrolyte to move the generated gas inside the exhaust pipe as if it were a moving valve. This system raises the electrolyte in the fuel electrolyte mixing tank and discharges it into the fuel electrolyte mixing tank.Since the gas generated by the discharge reaction is used, the amount of gas generated changes depending on the discharge flow, so the amount of circulating electrolyte is will also change automatically.

Furthermore, the gas generated is a byproduct when output is extracted from the fuel cell, and is of no use in terms of energy.

Circulating the electrolyte with this by-product means that no energy is lost, which is essentially different from the conventional method.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory view of a liquid fuel cell according to an embodiment of the present invention, and FIG. 2 is an enlarged view of the main parts thereof.

1 is a combustion electrode made of a porous nickel plate with platinum added as a catalyst and uses hydrazine as a reducing agent.

2 is a cathode terminal, and 3 is an air electrode made of a porous carbon electrode, which uses oxygen in the air as an oxidizing agent.

4 is an anode terminal, 5 is a frame made of synthetic resin, 6 is an electrolyte supply pipe, 7 is an electrolyte chamber of a cell, 8 is an electrolyte discharge pipe for the end of the reaction or the final reaction, 9 is the end of the reaction or the end of the reaction A fuel electrolyte, 10 is a unit fuel cell shown in FIG.
There is a positional difference h between the position of the electrolyte outlet 10' of the unit fuel cell 10 and the electrolyte level 12' of the fuel electrolyte mixing tank 11. It is below surface 12'.

12 is an electrolytic solution containing 30% caustic potassium solution mixed with 4% hydrazine hydrate; 13 is a fuel electrolyte mixing tank 11
The discharge liquid inlet pipe 14 from the discharge pipe 8 is a fuel tank containing fuel (hydrazine hydrate) to be consumed by the discharge reaction.

15 is an exhaust hole, 16 is a valve for supplying fuel stored in the fuel tank 14 in accordance with consumption by the discharge reaction, and 17 is a cock.

In a fuel cell having such a configuration, before starting discharge, when the tank 17 is opened, the electrolyte 12 is transferred from the fuel electrolyte mixing tank 11 to the electrolyte chamber 7 of the unit fuel cell 10 by hydraulic pressure.
The liquid flows through the discharge pipe 8 and is filled to the same level as the electrolyte 12 in the fuel electrolyte mixing tank 11 .

This liquid level is initially defined as liquid level 18.

Next, when discharge is started, gas is generated within the fuel cell 10.

The specific gravity of the gas is much lower than the specific gravity of the electrolyte, and the generated gas makes the apparent specific gravity of the battery-side electrolyte smaller than that of the electrolyte tank, causing the battery-side electrolyte to have buoyancy.

Therefore, if the inner diameter of the discharge pipe 8 is set to 7 mm or less, the gas generated by the surface tension of the electrolyte acts as if it were a moving valve, and the buoyancy of the electrolyte generated by the gas causes the electrolyte 9 in the discharge pipe 8 to move into units. Electrolyte chamber 7 of fuel cell 10
It rises without returning to its original state and is discharged into the fuel electrolyte mixing tank 11.

Then, due to the liquid pressure difference with the fuel electrolyte mixing tank, the electrolyte 12 is immediately supplied to the unit fuel cell 10 through the electrolyte supply pipe 6, and the discharge pipe 8 is filled to the same liquid level as the original liquid level 18. .

During the discharge reaction, the above-mentioned operations are repeated and automatically carried out, and the electrolyte is poured into each unit fuel cell 10 and the fuel electrolyte tank 1.
It circulates within 1.

Further, since the amount of gas generated increases or decreases depending on the load, there is no need to adjust the amount of electrolyte to be supplied, and the amount is automatically adjusted.

The important things to do in order to perform the above repetitive motions are:
The installation position of the electrolyte discharge pipe attached to the top of each unit fuel cell is lower than the electrolyte level 12' of the fuel electrolyte mixing tank 11, and the electrolyte level 18 of the unit fuel cell 10 is lower than the electrolyte level 12' of the fuel electrolyte mixing tank 11. is located between the electrolyte discharge pipes 8.

In other words, a positional difference h is provided.

If there is no positional difference h, and the liquid level is higher than 12',
If they are the same, there is no electrolyte in the electrolyte discharge pipe, so the valve action of electrolyte movement using the surface tension of the electrolyte cannot be performed, so only the generated gas flows through the electrolyte discharge pipe. The electrolyte is not discharged.

Therefore, the electrolyte cannot be circulated.

Second, the inner diameter of the electrolyte discharge pipe 8 should be 7 mm or less.

If a pipe with an inner diameter of 7 mm or more is used, the valve action of the electrolytic solution disappears, and the generated gas rises in the electrolytic solution due to buoyancy, but it replaces the electrolytic solution in the pipe and only the gas is exhausted.

In this example, the optimal inner diameter of the pipe was 3 to 5 mm.

Furthermore, when the inner diameter of the pipe is approximately 1 mm, the flow path resistance will slightly restrict the amount of liquid.

Thirdly, even when a large number of unit fuel cells are electrically connected in series or parallel, the pipes for discharging the electrolyte should not be connected in series, but must be connected in parallel as shown in Figure 1, and each unit fuel Unless the electrolyte discharge pipe 8 is provided for each battery 10, the circulation operation cannot be performed.

Further, in the present invention, since the buoyancy of the electrolyte caused by the generated gas is utilized, if the electrolyte discharge pipe 8 is turned downward or sideways, the circulation operation will not occur, so the electrolyte discharge pipe 8 of each unit fuel cell 10 is It must be connected to the exhaust liquid inlet pipe 13 which is installed above the electrolyte level 12' of the fuel electrolyte mixing tank 11 at an angle of elevation from the top of the fuel cell.

That is, the fuel electrolyte mixing tank is arranged so that the liquid level thereof is located between both ends of the electrolyte discharge pipe of the fuel cell.

Therefore, the method that utilizes the pressure of the generated gas can cause reflux even if the exhaust pipe is turned sideways or downwards, which is a major difference from the method of the present invention.

FIG. 2 is a comparison curve diagram of a fuel cell A according to the present invention and a fuel cell B using a conventional fuel electrolyte circulation pump, which were simultaneously discharged continuously at a constant current of 10A.

The fuel cell of the present invention can produce a stable output for a long time, but the conventional fuel cell B uses a part of the output to operate the fuel electrolyte circulation pump, so the output that can be extracted is small. Discharge must be stopped because maintenance of the circulation pump is frequently required during discharge.

As described above, in the present invention, the fuel electrolyte can be easily circulated using the buoyancy of the electrolyte generated by the gas generated by the discharge reaction and the surface tension of the electrolyte, and no energy is required for circulating the electrolyte. , the industrial value is great.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a liquid fuel cell according to an embodiment of the present invention, FIG. 2 is an enlarged view of a unit fuel cell main body, and FIG. 3 is a performance comparison curve diagram of a battery of the present invention and a conventional battery. 7 is an electrolyte chamber, 8 is a discharge pipe, 9 and 12 are electrolytes, 1
0 is a unit fuel cell, and 11 is a fuel electrolyte mixing tank.

Claims (1)

[Claims] 1. In a fuel cell that uses a fuel that generates gas by a discharge reaction, such as hydrazine, the electrolyte discharge pipe with an inner diameter of 7 mm or less provided for each unit fuel cell is connected to the fuel electrolyte tank at an elevation angle from the top of the unit fuel cell, and the fuel The liquid level of the electrolyte mixing tank is positioned between both ends of the electrolyte discharge pipe of the fuel cell, and the buoyancy of the electrolyte generated by the gas and the surface tension of the electrolyte are A fuel cell characterized in that an electrolyte is automatically discharged from inside the cell to a fuel electrolyte mixing tank, and the electrolyte is circulated between the fuel cell and the fuel electrolyte mixing tank according to a discharge flow.