JPS6316577A - Fuel cell - Google Patents

Abstract

PURPOSE:To maintain the temperature in the vicinity of the upper and lower ends of the cell stack of a fuel cell at the level substantially the same with the temperature in the vicinity of the central portion by forming a blind passage which communicates with only a manifold on the outlet side of a cooling gas, and whereby temperature raising/cooling gas can be spreaded, on a heat resistant insulating plate. CONSTITUTION:A plural line of a blind passage 11, which communicate with only a manifold 7' on the outlet side of a cooling gas, are formed on a heat resistant insulation plate 3. One of the cooling gas, whose temperature became high (about 180 deg.C) after it has absorbed the heat of stack, thus spreads and overflows in the passage 11 as shown in the dotted arrow. A heat insulating layer, whose temperature is maintained at a high temperature, is thus constructed between a cell stack 2 and a metal end plate 4, thereby the temperature of the whole cell stack 2 can substantially be maintained constantly and the improvement of the cell characteristics and life can be attained. d. cooling gas.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a gas-cooled fuel cell, particularly to a heat insulating structure for a cell star 7.

(b) Conventional technology battery stacks generate heat due to reaction heat during one operation;
Cooling gas (
The population temperature is approximately 135℃, the outlet temperature is approximately 180℃) and is cooled by circulating it to the specified operating temperature! Ii (approximately 190°C).

However, since the upper and lower ends of the cell stack are in contact with the outside air, heat is conducted to the metal end plates from the heat-resistant insulating plates installed at the upper and lower ends of the cell stack, and even if insulation is used, heat dissipation to the outside air is avoided. As a result, the temperature of the battery stack becomes lower at the upper and lower ends than at the center, creating a temperature gradient in the stacking direction, resulting in a problem of deterioration of battery characteristics.

(c) Purpose The present invention aims to solve the above-mentioned problems by maintaining the temperature near the upper and lower ends of the battery stack at the same temperature as the central portion.

(D) Structure The present invention forms a blind passage in the heat-resistant insulating plate interposed between the cell stack and the metal end plate, which communicates only with the cooling gas outlet side manifold and allows the heated cooling gas to diffuse. This insulating plate suppresses heat radiation from the end plate.

(e) Examples Embodiments of the invention will be described with reference to the drawings.

The battery stack (1) is constructed by stacking metal end plates (4) on the upper and lower end surfaces of a well-known cell stack (2) with heat-resistant insulating plates (3) interposed between the upper and lower end plates (4). Composed of 11 stitches.

However, in the cell stack, there are cooling gas channels (5
) is interposed in advance.

The inlet and outlet manifolds (7) (7') for the cooling power supply are attached to the opposing stacked circumferential surface of this TLl and strip stack, and the other opposing 8v heavy circumferential surface is used for each of the fuel gas and reaction air. Manifolds (not shown) are installed in parallel.

Between the cooling gas inlet and outlet manifolds (7) and 7', there is a conduit (1) having a blower (8) and a heat exchanger (9).
0) to form a circulation flow path for cooling gas (air). Cooling gas supplied to the inlet manifold (7); ζ
The cooling gas is divided into each gas flow path 5〉 of the cooling plate (6), and the cooling gas that takes away stack heat and rises in temperature to approximately 180°C is cooled to approximately 135°C in the heat exchanger (9). It is then sent back to the stack and cooled to maintain the cell at the specified operating temperature (approximately 190° C.).

At this time, as mentioned above, since the top and bottom surfaces of the battery frame/yield are in contact with the outside air, heat is radiated outside near the top and bottom of the cell stack (2) via the heat-resistant insulating plate (3) - gold gta end plate (4). However, the cell temperature in this area decreases.

As shown in FIGS. 3 and 4, the present invention is a heat-resistant insulating plate
) is formed with multiple rows of blind passages (11) that communicate only with the cooling gas outlet side manifold (7'), and a part of the cooling gas that has become high temperature (approximately 180'C) by removing stack heat is 5
As shown by the dotted arrow in the figure, the blind passageway (11) was diffused and filled. Therefore, a heat insulating layer maintained at a high temperature is formed between the cell stack (2) and the metal end plate (4), thereby blocking heat radiation from the vicinity of the upper and lower ends of the cell stack to the outside.

<Effect> As mentioned above, according to the present invention, blind passages are formed in the heat-resistant insulating plates installed at the upper and lower ends of the cell stack so that they are filled with the heated gas after cooling. It becomes possible to keep the temperature of the cell stack substantially constant vertically by blocking heat radiation from the plate, and it is possible to improve battery characteristics and life.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the outline of the battery stack, FIG. 2 is a perspective view of the main parts of the same as above, FIG. 3 is a partially enlarged perspective view of the pond stack according to the present invention, and FIG. 4 is a cooling system according to the present invention. Factor a of the system, No. 5 IyJ is an enlarged cross-sectional view of the main part same as above. 1: Battery stack 2: Cell stack 3: Heat-resistant insulation board
4: Metal end Fi 5: Cooling gas flow path 6: Cooling plate 7
．． 7': Cooling gas inlet and outlet manifold 8 Ni blower 9: @exchanger 11: Blind passage

Claims (1)

[Claims] A battery stack in which a cooling plate is interposed every few cells in a cell stack, and a heat-resistant insulating plate is installed between the upper and lower end surfaces of the stack and a metal end plate for tightening, and a cooling gas flow path of the cooling plate is provided. In a fuel cell comprising cooling gas inlet and outlet manifolds attached to opposing stacked circumferential surfaces of the stack that are open,
A fuel cell characterized in that a blind passage is formed in the heat-resistant insulating plate, communicating only with the outlet side manifold and allowing the heated cooling gas to diffuse.