JPS58133770A - Fuel cell - Google Patents

Abstract

PURPOSE:To detect abnormality by installing an abnormality monitoring device in a cooling system, and detecting the variation of mixing pressure to the cooling system. CONSTITUTION:A gas system which supplies a fuel gas 2 and an oxidizing gas 3, and a primary cooling system which controls heat generating by a chemical reaction in a fuel cell main body are connected to the fuel cell main body 1 consisting of layer- built plural unit cells and a cooling device. The heat is transmitted to a secondary cooling system 5 with a heat exchanger, and released to the outside. A gas moisture separating device 6 which acts as an abnormality monitoring device is installed in a cooling system 4, and thereby the amount of gas is measured. When the amount of gas changes sharply, the system is judged as abnormality. A pressure detector 7 which acts as another abnormality monitoring device is installed in the cooling system 4, and thereby pressure P1 in the cooling system is measured. Sharp increase of pressure P1 or the pressure difference between pressure P<1> and pressure P0 is detected. When the pressure difference becomes zero, the system is judged as abnormality, and a releasing valve 8 is opened to release a medium liquid, and the operation of the fuel cell is stopped. Therefore, flow in of the medium liquid to the fuel cell main body is prevented and the damage of the cell is suppressed in a minumum level.

Description

[Detailed description of the invention] The present invention uses a liquid medium to cool the fuel cell body. This invention relates to a fuel cell having a 41g system.

The main body of a conventional fuel cell is a unit cell that contains an electrolyte between an oxidizing gas electrode having an oxidizing gas flow path and a fuel electrode having a fuel gas flow path. A plurality of fuel cells are arranged with separators in between to prevent gases from mixing, and the fuel cell main body is housed in a container.

As a means for supplying oxidizing gas and fuel gas to the nine stacked fuel cell bodies, mania olds are fixed to the sides of the fuel cell body, and one of the opposing mania olds serves as an inlet and the other serves as an outlet. , oxidizing gas or fuel gas is supplied to each unit cell all at once.

9. In general, fuel cells need to maintain a constant temperature, so a cooling device is needed to cool down the excess heat generated when power is generated, and each unit cell is connected to a cooling system. It is located.

By the way, in conventional fuel cells, the pressure of the supplied fuel gas and oxidizing gas (air) is 25~/ll''G, whereas the cooling system uses pure water as a medium. If the temperature is 111!t-160UIi [,
In a sealed cooling system, from the relationship of saturated water vapor pressure, &3
The operating pressure is Kg/cIII"Gii degrees.

For this reason, the pressure balance within the fuel area pond is as follows: pressure inside the cooling quadrilateral > gas pressure.In the unlikely event that the cooling system that encloses the cooling medium is damaged due to corrosion, fatigue, etc. Due to the pressure, the medium flows into the fuel cell body,
This will result in a loss of battery performance.

The purpose of the fuel cell of the present invention is to detect damage to the cooling system without the liquid medium flowing into the fuel cell main body, and to minimize the discovery of damage and the damage caused by ants.

In the present invention, by operating the cooling system at a pressure lower than the pressure of the gas supplied into the fuel cell main body, even if the cooling system is damaged, the gas inside the fuel cell main body will only flow into the cooling system. Focusing on the fact that gas is not being discharged, we installed an A monitoring device in the cooling system, which detects fluctuations in the pressure of gas mixed into the cooling system, and detects abnormalities. It is something to do.

As shown in FIG. 1, the fuel cell of the present invention has a fuel cell body 1 consisting of a mantissa number of laminated brewing ponds and a cooling device.
A gas system for supplying fuel gas 2 and oxidizing gas 3 is connected to a primary cooling system 4 for controlling heat generated by chemical reactions within the fuel cell body, and the heat is further transferred to a secondary cooling system using a heat exchanger. It is propagated to the cooling system 5 and discharged to the outside.

Then, by operating with the pressure p of the secondary cooling system set to p<pe with respect to the gas pressure p of the fuel cell main body 1, the liquid medium of the cooling system 4 flows into the fuel cell main body 1. In addition, the next abnormal phenomenon that occurs when the cooling system 4 is damaged in the fuel cell main body l can be detected by the cooling system [4]. That is, the %AA in the medium of the cooling system 4 is 2.
If s2 gas is mixed in or the cooling system 4 is severely damaged, this pressure p.

will cause the phenomenon that p,=p. For this reason, the cooling system 4 is provided with a steam/moisture I/I device 6 as an abnormality monitoring device to measure the amount of gas, and if the amount of gas suddenly changes, it is determined that there is an abnormality. Ninth, a pressure detector 7 is provided in the cooling system 4 as another abnormality monitoring device, and the pressure p of the cooling system is constantly measured independently, and the sudden increase in the pressure p or the differential pressure between the pressure p and the pressure p is determined as follows: When the differential pressure becomes OK, it is determined that there is an abnormality, ps < ps (D While maintaining the pressure balance, the discharge pulp 8 installed in the gas supply system and cooling system 4
opening to release the medium and stop the operation of the fuel cell;
It prevents the medium from flowing into the fuel cell main body 1 and prevents this damage 1.
can be minimized.

When pure water is used as the medium in the cooling system, the saturated water vapor pressure percentage shown in Figure 2 is the same, and the lowest temperature zone of the medium is 17O.
If it is r, then it is 8 atmospheres or 7Kf! /Picture It is sufficient to operate the gas supply system at a pressure higher than IG.

If you get used to it like in the present invention, the cooling system will not damage the F15 battery itself! Jk'I# can be detected.

[Brief explanation of drawings]

Figure 1 is a schematic diagram of the fuel tank system;
The figure is a diagram showing the relationship between water temperature and saturated water vapor pressure.

Claims (1)

[Scope of Claims] 1. The fuel cell main body is housed in a container 6, in which the Rinii ponds are arranged in a solid volume of IjI number 1, and a cooling device is arranged for each of several unit #L ponds, A fuel cell in which a cooling system for circulating a liquid medium is connected to the cooling device, wherein the cooling system is provided with an abnormality viewing device, and a discharge pulp is provided to see the abnormality monitoring device. 2. Range of requirements for time l1fiII In item 1, the fuel cell is characterized in that the abnormality monitoring fcIi1 is comprised of a steam/moisture Sa and a pressure detector.