JPS6312348B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel temperature control device for fuel cells.

Traditionally, fuel cells have a media circulation type temperature control device inserted between closely stacked fuel cells to heat them up to promote reactions during startup and remove the heat generated during steady operation. and is used.

The configuration of one example of these is shown in FIG.

In FIG. 1, reference numerals 1 and 3 designate temperature control plates having reactive gas passages 2 and 4 provided on opposite sides thereof, respectively. A first heat exchange pipe 5 is provided between these two temperature control plates 1 and 3, and an inlet of the heat exchange pipe 5 is located between the temperature control plates 1 and 3.
A pump 6 that sends cold water or hot water to the first heat exchange piping 5 via a connecting piping 5a located outside of the pump 6 and the connecting piping 5a
The outlet is also connected to the connecting pipe 5a.

Next, its effect will be explained.

First, when starting up the fuel cell, in order to accelerate the reaction, the pump 6 sends hot water to the first heat exchange pipe 5, which applies heat to the temperature control plates 1 and 3, which are stacked above and below the temperature control plates. Heating the fuel cell. On the other hand, during steady operation, it is necessary to remove the heat generated in the fuel cell in order to prevent the fuel cell from being destroyed due to temperature rise. The heat generated by the fuel cell is transmitted from above and below to the temperature control plates 1 and 3, and further to the first heat exchange pipe 5 sandwiched between the two temperature control plates 1 and 3. Cold water is supplied to the first heat exchange pipe 5 by a pump 6 that has been switched to a different pipe line than that at startup, and the generated heat is transferred to the cold water and taken out from the temperature control plates 1 and 3. .

As mentioned above, conventional temperature control devices require a pump 6 to circulate cold water and hot water, require auxiliary power, and also require devices with moving parts (pumps, motors, etc.) as components. It has drawbacks such as lack of reliability due to the fact that it is

This invention seeks to eliminate the above drawbacks,
By allowing the enclosed medium in the heat exchange piping to circulate naturally, it is possible to eliminate the need for auxiliary power.

That is, the present invention comprises two temperature regulating plates arranged horizontally so as to face each other, each having a reaction gas passage on the opposite surface thereof, and a first temperature regulating plate disposed between these temperature regulating plates. The heat exchange piping consists of a second heat exchange piping having a radiator located higher than the position of the first heat exchange piping, and a third heat exchange piping having a heater located lower than the position of the first heat exchange piping. The present invention relates to a temperature control device for a fuel cell, in which an exchange pipe, a second heat exchange pipe, and a third heat exchange pipe are hermetically connected to one closed system, and a medium is sealed in the pipe so as to include a gas phase portion.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on drawings showing an embodiment of a temperature control device of the present invention.

FIG. 2 is a schematic perspective view showing an embodiment of the present invention, and the heat exchange piping is shown lifted upward to make it easier to understand.

In FIG. 2, numerals 1 and 3 are temperature control plates similar to those in the conventional example, and a first heat exchange pipe 5 is sandwiched between the temperature control plates 1 and 3. Reference numeral 7 denotes a radiator provided in the second heat exchange pipe located higher than the position of the first heat exchange pipe 5. Reference numeral 8 denotes a heater provided in the third heat exchange pipe, which is located lower than the position of the first heat exchange pipe 5.
These first heat exchange piping 5, second heat exchange piping and third
It is hermetically connected to the heat exchange piping to form a closed circuit, and after the inside is evacuated to a vacuum, a medium such as water or chlorofluorocarbon is sealed to contain the gas phase portion.

Next, the function of the temperature control device thus obtained will be explained in accordance with the order of heat transfer. First, when cooling a fuel cell (not shown), the heat generated in each layer of the stacked fuel cells is transferred from above and below to the temperature control plates 1 and 3 according to the temperature gradient, and then to the temperature control plates 1 and 3. 1 heat exchange piping 5. This heat evaporates the medium sealed in the first heat exchange pipe 5, and conversely, the temperature control plate itself is cooled by the heat of vaporization being absorbed. At this time, the steam generated in the first heat exchange pipe 5 rises through the connection pipe 5a and reaches the second heat exchange pipe having a radiator, where it is cooled by the outside air and condensed into a liquid, and due to its own weight it is heated to the first heat exchange pipe. Return to replacement piping 5. At this time, heat is also radiated from the enclosed medium in the third heat exchange pipe having the heater 8. As the radiator, a conventionally known radiator for fluid cooling having fins with good thermal conductivity can be used as appropriate.

Next, a method of heating each stacked fuel cell at the time of startup of the fuel cell will be explained.

As a heating means of the heater, for example, the outside of the pipe passing through the heater is heated by wrapping it with an electric heater, or the pipe is blown with hot air. The medium in the third heat conversion pipe is heated. The medium whose density has become smaller rises through the connecting pipe 5a due to the buoyant force based on the density difference with the medium in the first heat exchange pipe 5 and flows into the first heat exchange pipe 5, and the temperature control plate 1 .
In this way, the medium circulates within the piping without using power, and the fuel cell can be efficiently cooled and heated.

Note that the first heat exchange pipe 5 and the connection pipe 5a can be integrated into a pipe, but in order to eliminate the need for electrically insulating the radiator 7 and the heater 8, the connection pipe 5a may be Electrically insulating materials may be used to float the heat sink 7 and heater 8 from the potential of the fuel cell.

As mentioned above, the fuel cell temperature control device of the present invention does not require a pump for medium circulation, so it requires less auxiliary power, and therefore the electrical conversion efficiency of the fuel cell itself can be increased. Moreover, since reliability can be improved, it has great practical value.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing a conventional fuel temperature control device, and FIG. 2 is a schematic perspective view showing an embodiment of the fuel cell temperature control device of the present invention. (Main symbols in the drawing), 1, 3: Temperature control board, 2,
4: Reaction gas passage, 5: First heat conversion pipe, 5a:
Connection piping, 7: radiator, 8: heater.

Claims (1)

[Scope of Claims] 1. Two temperature control plates arranged horizontally to face each other, each having a reaction gas passage on the opposite side, and arranged between these temperature control plates. Consisting of a first heat exchange pipe, a second heat exchange pipe having a radiator located higher than the position of the first heat exchange pipe, and a third heat exchange pipe having a heater located lower than the position of the first heat exchange pipe, 1st
The heat exchange piping, the second heat exchange piping and the third heat exchange piping are hermetically connected to one closed system,
A temperature control device for fuel cells in which a medium is sealed in the piping to include a gas phase portion. 2. The temperature control device for a fuel cell according to claim 1, wherein the sealed connection is made by an electrically insulating connection pipe.