JPH03119665A - Fuel cell fastening device - Google Patents

Abstract

PURPOSE:To uniformly fasten a cell stack by penetratingly providing fastening studs in the laminating direction in the cell stack in a fuel cell fastening device fastening and fixing the cell stack. CONSTITUTION:Fastening studs 10 are penetratingly provided in the laminating direction in a cell stack 1, and they are fastened with nuts 5 from the outside of upper and lower fastening plates 2 and 3. Holes 12 through which studs 10 are penetrated are provided on cells 11 constituting the stack 1, a caulking material 14 is filled in grooves 13 of cells 11 located around holes 12 so that the reaction gas flowing through grooves 13 is not leaked through the holes 12, and insulating materials 15 are fitted around studs 10. Upper and lower fastening plates 2 and 3 are made nearly the same size as the cell stack 1.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a fuel cell, and in particular to a fuel cell in which the tightening structure of a cell stack formed by stacking a plurality of unit cells has been improved. This invention relates to a battery tightening device.

(Prior Art) Fuel cells are conventionally known as devices that directly convert chemical energy contained in fuel into electrical energy. In this fuel cell, a unit cell is composed of a fuel electrode and an oxidizer electrode, a plurality of these unit cells are stacked to form a cell stack, and fuel gas and oxidant gas are supplied to a manifold provided on the side of the cell stack. The electrochemical reaction that occurs at this time is used to extract electrical energy from between the electrodes, and as long as fuel gas and oxidant gas are supplied, electrical energy can be extracted with high conversion efficiency. It is something that can be done.

Further, the unit capacity of such a fuel cell is said to be proportional to the electrode area or the number of electrodes stacked, and in order to increase the capacity, it is essential to increase these.

FIGS. 4(A) and 4(B) show an example of a conventionally used fuel cell. That is, a cell stack 1 is constructed by stacking a plurality of unit cells, and an upper clamping plate 2 is disposed on the upper surface of the cell stack 1, and a lower clamping plate 3 is disposed on the lower surface of the cell stack 1. Tightening studs 4 at the four corners of the attachment plate 2.3
are attached, and by tightening the two lower clamping plates with nuts 5, the cell stack 1 sandwiched between them is tightened. In addition, the upper and lower tightening plates 2゜3
Usually, a thick plate is used so as not to be deformed by the tightening force of the tightening stud 4.

(Problems to be Solved by the Invention) However, the conventional fuel cell tightening device configured as described above has the following problems to be solved.

In other words, as mentioned above, when increasing the capacity of fuel cells,
Although it is necessary to increase the electrode area or the number of stacked unit cells, the method of increasing the number of stacked unit cells is not preferable due to transport restrictions, so it is necessary to increase the electrode area.

However, if the electrode area is increased, the area of the upper and lower clamping plates 2 and 3 will also increase accordingly, so in the conventional tightening method of tightening the four corners, the upper and lower clamping plates 2 and 3 tend to deform into an arched shape. Become. When the upper and lower clamping plates 2.3 are deformed in this way,
The tightening force does not act uniformly in the vertical direction, and the force that tightens the cell stack 1 becomes uneven, resulting in decreased battery performance and excessive tightening force being applied only to the ends of the cell stack.
There was a possibility that the ends could be damaged. In order to prevent the upper and lower clamping plates 2.degree. 3 from deforming, a method of increasing the thickness of these plates could be considered, but this was not preferable because it would increase the weight of the fuel cell.

The present invention was proposed in order to eliminate the above-mentioned drawbacks, and its purpose is to provide a fuel cell tightening device that can uniformly tighten a cell stack.

[Structure of the Invention] (Means for Solving the Problems) The fuel cell tightening device of the present invention tightens the upper and lower ends of a cell stack formed by stacking a plurality of unit cells each consisting of a fuel electrode and an oxidizer electrode. In a fuel cell tightening device for tightening and fixing the cell stack by arranging a mounting plate and tightening the upper and lower clamping plates with a tightening stud, the tightening stud penetrates inside the cell stack in the stacking direction thereof. It is characterized by the fact that it is arranged as follows.

(Function) According to the fuel cell tightening device of the present invention, since the tightening stud is disposed through the cell stack, the tightening force is uniformly applied to the upper and lower tightening plates and the cell stack, so that the upper and lower tightening It is possible to prevent the attachment plate from deforming.

(Example) Hereinafter, an example of the present invention will be specifically described based on FIGS. 1 and 2. Incidentally, the same members as those of the conventional type shown in FIG. 4 are given the same reference numerals, and the description thereof will be omitted.

In this embodiment, as shown in FIGS. 1(A) and 1(B), a tightening stud 10 used for tightening the cell stack 1 is arranged so as to penetrate through the inside of the cell stack 1 in the stacking direction. The upper and lower clamping plates 2 and 3 are tightened from the outside by nuts 5. Also, tightening stud 1
Figure 2 (A) shows the internal structure of the cell stack 1 through which o passes through.
Shown in (B). That is, the cells 11 constituting the cell stack 1 are provided with holes 12 through which the tightening studs 10 pass, and in the grooves 13 of the cells 11 located around the holes 12, the reaction gas flowing in the grooves is A caulking material 14 is filled to prevent leakage through the hole 12. Also,
To ensure insulation between the clamping stud 10 and the cell 11, an insulating material 15 is installed around the clamping stud.

In addition, upper and lower clamping plates 2 disposed above and below the cell stack 1
, 3 are formed to have approximately the same size as the cell stack 1.

In the fuel cell tightening device of this embodiment having such a configuration, the tightening stud 10 passes through the cell stack 1.
is installed, so when the tightening stud 10 is tightened, no tightening force is applied to a part of the upper and lower tightening plates 2.3, so the upper and lower tightening plates 2 and 3 will not be deformed. , the cell stack 1 can be tightened uniformly. Further, unlike the conventional case, the clamping force does not act only on the four corners of the upper and lower clamping plates 2.3, so no bending force is applied to the four corners, and the ends of the cell stack 1 are not damaged. Also,
It is also possible to reduce the thickness of the upper and lower clamping plates 2.3.
It can also contribute to reducing the weight of fuel cells.

In this way, according to this embodiment, the cell stack 1 can be tightened uniformly, and the thickness of the upper and lower tightening plates can be made thinner, thereby reducing the weight of the fuel cell.

It should be noted that the present invention is not limited to the above-described embodiments, and the mounting position of the tightening stud can be changed by considering the arrangement position so that the tightening force when tightening the tightening stud is uniformly applied to the cell stack. is not particularly limited. Alternatively, as shown in FIGS. 3A and 3B, the cell 21 may not be grooved only around the hole 12 through which the tightening stud 10 passes, so that the reaction gas does not leak. .

[Effects of the Invention] As described above, according to the present invention, the tightening studs for tightening the cell stack and the upper and lower tightening plates can be simply provided by penetrating inside the cell stack in the stacking direction. By this means, it is possible to provide a fuel cell tightening device that can uniformly tighten a cell stack.

[Brief explanation of drawings]

Figure 1 shows an embodiment of the fuel cell tightening device of the present invention, in which (A) is a plan view, (B) is a front view, and Figure 2 is a first embodiment of the fuel cell tightening device of the present invention.
FIG. 3 is an enlarged view of the main part of the figure, (A) is a cross-sectional view, (B) is a longitudinal cross-sectional view, and FIG. 3 shows another embodiment of the present invention.
A) is a cross-sectional view, (B) is a longitudinal cross-sectional view, FIG. 4 shows an example of a conventional fuel cell tightening device, and (A) is a plan view.
(B) is a front view. 1...Cell stack, 2...Upper tightening plate, 3...
Lower tightening plate, 4... tightening stud, 5... nut, 10... tightening stud, 11... cell, 12...
... hole, 13 ... groove, 14 ... caulking material, 15
...Insulating material, 21...Cell.

Claims (1)

[Scope of Claims] Clamping plates are provided at the upper and lower ends of a cell stack formed by stacking a plurality of unit cells each consisting of a fuel electrode and an oxidizer electrode, and the upper and lower clamping plates are tightened by tightening studs. A fuel cell tightening device for tightening and fixing the cell stack, characterized in that the tightening stud is disposed to penetrate inside the cell stack in the stacking direction thereof.