JPH0589900A - Fuel cell - Google Patents

Abstract

PURPOSE:To ensure protection after stop of operation and improve the life of an electrode and cell and shorten the rise-up time at the time of restart. CONSTITUTION:In a fuel cell where hydrogen is led to a fuel-pole-side electrode 6 and oxygen is led to an air-pole-side electrode 5 to generate electricity, the upper and lower portions of the fuel cell are held between insulating plates 1 where PTC heaters 1a having PTC characteristics are respecviely arranged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell, and more particularly to a high temperature reaction type fuel cell.

[0002]

2. Description of the Related Art In the case of a high temperature type of a reaction temperature of a fuel cell, a solid organic electrolyte (SPE) type has a reaction temperature of 130 to 150 ° C., and a phosphoric acid type electrolyte type has a reaction temperature of 180 to 150 ° C.
210 ° C., molten carbonate electrolyte type is 630 to 670 ° C.,
The high temperature solid electrolyte type has a temperature of up to 1000 ° C. It takes time to reach a high temperature after returning from this reaction temperature to room temperature, and 1) after operation is stopped, it is necessary to keep warm to protect the electrodes.

2) A heater having a good response is required in order to shorten the rising time at the time of restarting.

3) At the time of heat retention, it is required to control the temperature so that the temperature of the battery main body does not rise excessively, and there is a problem to simplify the above items for practical use.

In response to this, the prior art is of a type in which an electrolytic solution is circulated as shown in Japanese Patent Laid-Open No. 57-55070, and a heater is provided in a part of the circulation path to obtain good mobility characteristics. Fuel cells have been proposed.

[0006]

However, the conventional technique has a problem of corrosion fatigue (lifetime) of the entire apparatus because a strong alkali is circulated in the electrolytic solution.

Further, the concentration of the electrolytic solution is lowered by absorbing the steam (water) and carbon dioxide gas in the air, which causes the output to be reduced.

The present invention has as its object to solve the above-mentioned problems, provides reliable protection after an operation stop, expects an improvement in the life of the electrode-battery, and provides a shortened start-up time upon restarting. To do.

[0009]

The technical means for achieving the above object is to introduce hydrogen into the fuel electrode side electrode, the air electrode side electrode, and the fuel electrode side electrode, and to introduce oxygen into the air electrode side electrode. In the fuel cell for introducing electricity to generate electricity, the upper and lower sides of the fuel cell are sandwiched by insulating plates on which PTC heaters having PTC characteristics are arranged.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Will be explained with reference to.

FIG. 1 shows a conventional phosphoric acid fuel cell 1
It is an exploded perspective view of 0. An insulating plate 1, a cooling plate 2 made of a carbon plate, a carbon sheet 3,
A grooved air electrode side separator 4 made of a carbon plate, an air electrode side electrode 5 made of carbon-platinum, a fuel electrode side electrode 6 made of carbon-platinum, and a grooved fuel electrode side separator 7 made of a carbon plate. ..

Air containing oxygen is introduced into a plurality of air introducing portions 4a arranged in the grooved air electrode side separator 4. On the other hand, in the grooved fuel electrode side separator 7, hydrogen is introduced into the plurality of air introduction portions 7a of the grooved fuel electrode side electrode 7 arranged in the direction perpendicular to the grooved air electrode side separator 4. With such a configuration, oxygen ions are generated in the air side electrode 5 and hydrogen ions are generated in the fuel side electrode 6. Between the air electrode side electrode 5 and the fuel electrode side electrode 6, the hydrogen ions of the fuel electrode side electrode 6 are attracted to the oxygen ions of the air electrode side electrode 5, and the reaction of producing hydrogen and oxygen occurs. At the same time, the electrons e move in the conducting wire to generate a current.

Since other details are the same as those of a general phosphoric acid fuel cell, they are omitted here.

The insulating plates 1 arranged above and below the fuel cell body 10 are made of alumina ceramics, and the insulating plate 1 is fastened to the fuel cell body with bolts or the like.

A loop-shaped PTC heater 1 having a heater function and self-temperature control on one surface of the insulating plate 1.
Arrange a. Both ends of this PTC heater 1a are terminals 1
b is provided. This PTC (Positive)
The Temperature Coefficient) heater 1a is a heat-sensitive resistance element having a positive temperature characteristic that shows an increase in resistance value when a certain temperature (Curie point) is reached.
Therefore, in the PTC that is self-heated by applying a voltage, the current increases as the temperature decreases, and the PTC stabilizes at a substantially constant temperature. That is, the PTC serves both as a heating element and a temperature controller.

In other words, the PTC heater 1a cuts off the electricity from the terminal 1b when it reaches a certain set temperature, and the electricity flows again when the temperature of the main body falls, and it has both a heater function and a self-control function.

The PTC heater 1a is provided by screen printing, and is formed by bending a plurality of loops each having a thickness of 1 mm and a width of 5 mm.

In the present invention, the PTC heater is used as the insulating plate 1.
Although arranged above, the PCT heater may be embedded in the insulating plate.

[0019]

As described above, the present invention has the following effects.

In the high temperature type fuel cell, 1) the protection after the operation is stopped can be surely performed, and the life of the electrode-cell can be improved.

2) It is possible to shorten the start-up time at restart.

3) By applying PTC, the temperature control system of the battery body (limited to heat retention).

During operation, a heating / cooling system can be used).

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a fuel cell of the present invention.

FIG. 2 is a plan view of an insulating plate on which a PTC heater is arranged.

FIG. 3 is a side view of an insulating plate on which a PTC heater is arranged.

[Explanation of symbols]

 1a insulating plate, 1b PTC heater, 5 air electrode side electrode, 6 fuel electrode side electrode, 10 fuel cell.

Claims (1)

[Claims] 1. A fuel cell in which hydrogen is introduced into a fuel electrode side electrode, an air electrode side electrode, and a fuel electrode side electrode, and oxygen is introduced into the air electrode side electrode to generate electricity. A fuel cell characterized in that the upper and lower parts are sandwiched by insulating plates on which PTC heaters having PTC characteristics are arranged.