JPS5929382A - Insulating plate used as terminal part for fuel cell - Google Patents

Abstract

PURPOSE:To prevent any gas leakage which might be caused due to a large thermal deformation of fluorine system resin by forming a heat-resistant insulating plate by the use of a laminated plate, which is prepared by laminating plural pieces of glass cloth impregnated with a silicone resin before hot press is performed. CONSTITUTION:A heat-resistant insulating plate 17 consists of a laminated plate prepared by impregnating glass cloth with a silicone resin before drying, then laminating plural pieces of thus treated glass cloth before hot press is performed at 250 deg.C. The insulating plate is called 1G-13, has thermal resistance of 300-400 deg.C, a thermal expansion coefficient in thickness direction of 5.3X10<-5>/ deg.Cand a thermal expansion coefficient in longitudinal direction of 6.3X10<-5>/ deg.C, and does not cause permanent contraction. When a battery is assembled by using the laminated plate 17, since the thermal deformation of the laminated plate 17 is extremely small, there is no possibility that gass leaks through gaps which were conventionally caused.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a heat-resistant insulating material interposed between an end plate of a battery stack and a metal end plate that presses against the stack by a fastener I.

As shown in FIG. 1, a conventional battery stack (1) includes a unit cell (2) in which an electrolyte matrix is interposed between negative and positive gas electrodes,
Carbonaceous gas separation plates (5) with reaction gas supply grooves (31 (41) arranged on both sides are arranged alternately, and current collector plates (6) and heat-resistant insulating plates (with fluororesin legs) are arranged on the upper and lower end surfaces in sequence. 7)
The aluminum end plates (8) are stacked together via the upper and lower end plates (8), and the upper and lower end plates (8) are firmly tightened using a clamping member (not shown).

The manifold (9), which is attached to the stacking surface of the battery stack for supplying each reaction gas, has a frame-shaped seal member aO) made of 7-component rubber sandwiched between the manifold (9) and the surrounding collar.
) is screwed onto the stack end plate (8).

However, the end plate (8), the insulation plate (7) and the gas separation plate (5)
The constituent materials are aluminum, fluororesin, and carbon, respectively, and their thermal expansion coefficients are in the relationship of carbon, aluminum, and fluororesin. Therefore, the high temperature during battery operation (160~1
90°C) and at low temperatures during non-operation, they expand and contract at different rates, but the thermal deformation of fluorine-based resins in particular is extremely large, and after expansion, they contract and do not recover even during battery operation.4QQ+u
For the long insulation board (7), the permanent shrinkage in the longitudinal direction is 0 to 4.
．． Therefore, a gap (8) was created in the sealing surface of the manifold (9) in the stacking direction, causing gas leakage.

DISCLOSURE OF THE INVENTION The purpose of the present invention is to prevent gas leakage caused by large thermal deformation of fluororesin, and its feature is that glass cloth impregnated with silicone resin is laminated as a heat-resistant insulating plate. The key point is that a hot-pressed laminate is used. Furthermore, the laminated plate has an uneven fit with the end plate at the periphery or near the corner, thereby further suppressing thermal deformation.

Embodiment An embodiment of the present invention will be described with reference to FIG. 2, where the same symbols as in FIG. 1 are used for the corresponding parts.

The heat-resistant insulating board (17) of the present invention is produced by impregnating a glass cloth with silicone resin and drying it, and then laminating a plurality of these sheets.
It is a laminated plate hot-pressed at 0'C and is called 1G-1'5 (trade name). The heat resistance of this laminate is 6
00 to 400°C, and the temperature is 3 x 16°C, and the thermal expansion in the longitudinal direction is 0 when the temperature is raised from room temperature to 200°C for an insulating board (17) with a first dimension of 400°. , only one wing, and does not undergo permanent shrinkage unlike the conventional fluorine resin insulating board (7).

Therefore, if this laminate plate (1'7) is used instead of the conventional fluororesin insulating plate (7) and assembled in the same manner as shown in Fig. 1,
As shown in FIG. 2, since the heat broiling of the laminated plate is extremely small, there is no gap (8) and no gas leakage as in the conventional case. In addition, protrusions or convex portions (8) are formed around or near the corners of the aluminum end plate (8), and these protrusions or convex portions (8) are formed on the laminated plate (by hot pressing). If assembled by fitting into the grooves or the four parts (171), the expansion and contraction of the laminate plate 07 can be further suppressed and the sealing performance of the manifold (9) can be further improved.

Figure 3 is an enlarged cross-sectional view of the main part of the terminal drawer, with a terminal post (12) in the central recess of the gold-plated copper terminal plate (6).
(7) Base end flange (12) Full fitting L, conical terminal post (12)
C, 4* H plate (1η and the end plate (8) fitted with the flange insulating sleeve (14) is passed through the negative, and the end plate (8) is screwed to the tip thereof) (141) to be fixed.

Effects According to the present invention, as a heat-resistant insulating plate interposed between the terminal plate of the battery stack and the metal end plate that presses the stack,
A laminated board made by hot-pressing glass cloth impregnated with silicone resin has extremely low thermal expansion and contraction compared to conventional fluororesin boards, and does not impair the sealing performance of the manifold due to thermal deformation of the insulating board. 1. Gas leakage from between the sealing surfaces in the stacking direction of the stack can be prevented.

Furthermore, if four stripes or four portions that fit into the protrusions or protrusions formed around or near the corners of the end plates are formed on this laminated plate, thermal deformation of the insulating plate can be further suppressed and sealing performance can be improved. can.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a main part of a battery stack including a conventional insulating plate, Fig. 21g1 is a cross-sectional view of a main part of a battery stack equipped with an insulating plate according to the present invention, and Fig. 6 is a cross-sectional view of a main part of a battery stack equipped with an insulating plate according to the present invention. ``This is a side view. (1)...Battery stack, (2j...
・Unit cell, (3) (4)... Reaction gas supply groove, (5)... Gas separation plate, (6)...
Terminal board, (7)...Insulating board (conventional), uη...
...Insulating plate (laminated board of the present invention), f8)...
...End plate, (9)...Manifold, convex strip or convex portion, 07)...Four stripes or concave portion of insulating plate.

Claims (1)

[Scope of Claims] Terminal insulation of a fuel cell characterized by being composed of a hot-pressed laminated sheet of impregnated glass cloth), p
Q. (2) Claim No. 1, characterized in that the laminate of piJ 1 is provided with grooves or four parts that fit into the protrusions or protrusions formed around or near the corners of the end plate. Terminal insulating plate of fuel cell according to item 1.