JPH0479475B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Fields of Application This invention relates to a fuel that has a structure in which a large number of battery cells are stacked, each of which has an anode (fuel electrode) and a cathode (oxidizer electrode) sandwiched between an electrolyte layer such as sulfuric acid or the like. For batteries, an electrolyte layer is formed in a synthetic resin frame,
The present invention relates to a fuel cell in which an electrolyte passageway and a liquid chamber can be made completely airtight when laminated with a metal frame forming a gas chamber, and the entire fuel cell can be made extremely small and lightweight.

BACKGROUND TECHNOLOGY A fuel cell is a power generation device that directly converts the chemical energy of the fuel into electrical energy while electrochemically oxidizing the fuel.It was first put into practical use as a power source for spacecraft, and then became more popular as a compact and lightweight device. Various improvements have been made with the aim of improving

The most common type of fuel cell, a hydrogen-oxygen fuel cell, consists of a so-called battery cell in which a fuel electrode (negative electrode, anode electrode) and an oxidizer electrode (positive electrode, cathode electrode) are arranged with an electrolyte layer in between. and oxygen as fuel and oxidant, hydrogen is combusted.This combustion consists of an oxidation reaction due to the contact of the fuel gas to the anode electrode, a reduction reaction due to the contact of the oxidant gas to the cathode electrode, and an external By connecting the two poles at
No., Special Publication No. 57-59631).

In such a hydrogen-oxygen fuel cell, in a type that uses sulfuric acid as the electrolyte, the sealing structure of the electrolyte is particularly important, and since the reactant gas is also a flammable gas, it is necessary to ensure complete leakage prevention.

Conventionally, a synthetic resin frame was used for the electrolyte layer and the gas chamber, and these were laminated with adhesive (Japanese Patent Publication No. 1983-
Furthermore, a structure has been proposed in which the synthetic resin frame is eliminated by forming the electrolyte layer and gas chamber with an asbestos frame (Japanese Patent Publication No. 56-42107). Furthermore, a structure has been proposed (Japanese Patent Publication No. 1983-6111) in which a frame made of synthetic resin is used and an elastomer layer is used to seal the electrolyte passage hole provided in the frame.

In addition, such hydrogen-oxygen fuel cells have excellent energy efficiency, but what is not converted into electrical energy becomes heat, and the temperature reaches 80°C or higher depending on the type of electrolyte used during operation. Since water is generated during operation, hydrogen gas is circulated to remove and cool the generated water.
Measures have been taken to circulate and cool the electrolyte solution and various gases, but the cooling capacity has been insufficient.

For this reason, measures are taken such as placing cooling water pipes between the stacked electrolyte layers, anode, and cathode gas chambers and cooling media such as water with an external heat exchanger. Proposals include using a heat pipe (Japanese Patent Publication No. 56-54664) or a configuration in which only the required electrode side is cooled (Japanese Patent Publication No. 57-6229). There were various problems regarding gender.

Therefore, in a stacked fuel cell having cooling passages, it is essential to seal the passage holes through which fluid is distributed and supplied or collectively led out to the electrolyte layer, gas chamber, and each chamber of the cooling passage, but it is necessary to maintain complete airtightness. However, the conventional seal structure described above has been insufficient to reduce the size and weight of fuel cells.

Purpose of the Invention The present invention provides a stacked fuel cell having a cooling structure for maintaining the operating temperature at an appropriate temperature, which has a simple structure with good manufacturability, reduces the size and weight of the fuel cell, and has a complete structure. The purpose of the present invention is to provide a fuel cell having a configuration that provides airtightness.

Structure of the Invention This invention consists of stacking three passages with heat transfer fins built into a thin metal frame via a partition plate, with the intermediate passage serving as a cooling medium passage and both sides serving as an anode gas or cathode gas passage. It consists of a laminated metal frame laminate, a synthetic resin electrolyte frame sandwiched between electrode plates, and a large number of battery cells each having an anode and a cathode arranged therein. The passage hole is used as a distribution passage for electrolyte liquid, gas, or a cooling medium, and when an anode gas or cathode gas flows in or out, it communicates with the gas distribution passage and passes through a sealed passage provided in the cooling medium passage. Further, a ring spacer made of synthetic resin having a length between adjacent synthetic resin frames is fitted into the electrolyte liquid passage hole and brought into contact with the synthetic resin frame via an O-ring to form an electrolyte liquid passage hole. It has a seal structure that allows electrolyte to flow into and out of the electrolyte layer in the synthetic resin frame between the electrode plates from the small hole that communicates with the hole in the synthetic resin frame. A ring-shaped retainer seal made of synthetic resin with an elastic sealing material arranged on the inner peripheral surface is interposed between the stacked adjacent metal frame laminates, and an elastic seal whose wall thickness becomes thinner when the retainer sealing material is pressed and stacked is interposed between the stacked metal frame laminates. This fuel cell is characterized in that it has a seal structure configured to hold the fuel cell.

In other words, this invention forms an electrolyte layer with a synthetic resin frame having an electrolyte storage portion inside and two electrode plates placed on both sides of the frame, and has eight protrusions for passage holes around the frame. A roughly rectangular thin plate frame with a
Inside the frame, corrugated fins with the same height as the plate thickness are placed, and two partition plates placed on both sides form a metal frame that forms a cooling passage, and the metal frame has the same structure as the cooling passage metal frame. Two metal frames with corrugated fins placed inside the frames to form gas passages are stacked on both sides and are joined together by brazing.
In a fuel cell formed by pressing and stacking multiple sets of metal frame laminates having passages and synthetic resin frames forming an electrolyte layer alternately, holes are drilled in eight protrusions provided around each thin metal plate frame. The holes formed in the upper and lower protrusions of each synthetic resin frame are used as electrolyte passage holes in the stacking direction, and the synthetic resin has a length between adjacent synthetic resin frames. A ring spacer made of aluminum is fitted into the electrolyte passage hole, an O-ring is placed with recesses formed in the corners of both sides of the ring spacer, and the O-ring is brought into contact with the synthetic resin frame via the O-ring, thereby sealing the electrolyte passage. A sealing structure for each fluid distribution passage hole is formed by interposing a synthetic resin ring-shaped retainer sealing material with an elastic seal on the inner circumferential surface between adjacent laminated metal layers to form a sealing structure for the hole. This is a fuel cell characterized by forming a.

Effects of the Invention The fuel cell according to the present invention includes an anode, a cathode gas, and a cooling medium passage made of a metal frame that can be joined by brazing, a synthetic resin frame sandwiched between electrode plates, and an electrolyte layer formed inside the frame. Since these are laminated and pressed, a face seal is obtained on each frame, and the structure is essentially airtight and compact.The laminated seal structure of each fluid distribution passage has a synthetic resin ring. Although it has a simple configuration using a spacer or retainer sealing material, it is an efficient sealing structure that is easy to manufacture and assemble and takes into consideration the basic laminated configuration described above, and can maintain complete airtightness.

Preferred Embodiments of the Invention In the present invention, if the synthetic resin frame forming the electrolyte layer can be provided with distribution passage holes for the electrolyte solution, its shape and dimensions can be appropriately selected depending on the type of fuel cell, application, etc. Any material may be used as long as the material is used, but in consideration of sealing effect and corrosion resistance, fluorine resin is preferable.

In addition, the ring spacer forming the electrolyte distribution passage hole and the retainer sealing material forming the gas distribution passage hole may be made of ring-shaped synthetic resin material according to the required size and shape of the hole. In consideration of sealability, it is preferable to use the same material or synthetic resin with the same composition as the synthetic resin frame.

Any structure can be applied to the electrode plate, such as a structure in which a mesh-shaped electrode coated with a catalyst is attached to a known gas-permeable membrane.

In this invention, the metal frame can be provided with distribution passage holes for the cooling medium or anode and cathode gases, and as long as it can be brazed, its shape and dimensions can be appropriately selected depending on the type of fuel cell, application, etc. Any material may be used, but aluminum alloy is preferable in consideration of thermal efficiency and weight reduction, and has excellent brazing properties.

In addition, the heat transfer fins built into the metal frame are
Depending on the type of cooling medium such as water, oil, or fluorocarbons, or the type of gas, it can be used without obstructing the fluid passage.
and to obtain a uniform passage within the passage,
Various types, sizes, and materials can be applied, taking into account the fin shape, corrugation direction, etc., and those with slits or small holes in the fins themselves. Considering thermal efficiency, weight reduction, and brazingability, aluminum alloy is preferred.

Furthermore, when anode gas or cathode gas flows in or out, a sealed passage that communicates with the gas distribution passage and is provided in the cooling medium passage may be provided as a separate member from the metal frame or by forming a groove in the metal frame. Good.

Disclosure of the Invention Based on Drawings FIG. 1 is a longitudinal sectional view of a fuel cell showing a laminated seal structure of an electrolyte distribution passage hole according to the present invention. FIG. 2 is a longitudinal cross-sectional view of a fuel cell showing a laminated seal structure of a reactive gas distribution passage hole according to the present invention. FIG. 3 is a front view and a cross-sectional explanatory view of a metal frame laminate showing a cooling passage structure according to the present invention. FIG. 4 is a front explanatory view of the synthetic resin frame,
FIG. 5 is an explanatory front view of the metal frame. FIGS. 6 and 7 are a front view and a side view of a fuel cell using the cooling passage structure according to the present invention.

The stacked hydrogen-oxygen fuel cell according to the present invention includes a cooling medium passage 2 and an anode gas (hydrogen gas) passage 3.
When the metal frame laminate 1 made of an aluminum alloy integrally joined by brazing and forming the cathode gas (oxygen gas) passage 4 and the electrode plate 7 are closed on both sides to form the electrolyte layer 6, the synthetic resin frame 60 is formed. Two header plates 9 are laminated alternately, and the header plates 9 are laminated with pressure around each frame with a plurality of bolts 8 passing through the header plates 9.

The synthetic resin frame 60, which together with the electrode plate 7 constitutes the electrolyte layer 6, consists of a rectangular frame with a rectangular opening in the center, as shown in FIG. A protrusion 61 for drilling holes 16 and 17 is provided.

Further, the electrode plate 7 that contacts both sides of the synthetic resin frame 60 and closes the same is composed of a mesh-shaped copper electrode coated with a catalyst and adhered to a gas permeable membrane.

As shown in FIG. 3B, each metal frame made of aluminum alloy constituting a set of metal frame laminates 1 is connected to the cooling passage frame 2 via the cooling passage frame 20 and the partition plate 5.
Each metal frame 20, 30, 40 has eight passage hole protrusions 21,
31, 41, each corrugated fin 2 with the same height as the plate thickness is placed inside the frame.
3, 33, and 43 are arranged.

As shown in FIG. 7, the header plate 9 includes:
In addition to a large number of bolt holes for tightening, eight holes are provided in which connectors 18 for various fluid supply pipes or outlet pipes are installed.

The eight holes for the connectors 18 match the positions of the passage holes 10 to 17 of the metal frame laminate 1, which is laminated in large numbers. , 11, cathode gas passage holes 12, 13, horizontally cooling medium passage holes 14, 1
5. Electrolyte passage holes 16 and 17 are arranged vertically.

Except for the cooling medium passage holes 14 and 15, the upper side of each passage hole set constitutes a supply side, and the lower side constitutes a discharge side.

Due to the above-described laminated structure, the passage holes 10 to 17, which serve as fluid distribution passages, communicate in the laminated direction.
As shown in FIG. 1, the electrolyte solution passage holes 16 and 17 are formed by fitting a synthetic resin ring spacer 62 having a length between adjacent synthetic resin frames 60 into the electrolyte solution passage hole, so that the outer circumference of the ring spacer 62 abut against the synthetic resin frame 60 via the O-ring 63,
A passage hole 16 for distributing the electrolyte solution is configured so that the electrolyte solution can flow into and out of the electrolyte layer 6 in the synthetic resin frame 60 between the electrode plates 7 through the small hole communicating with the hole in the synthetic resin frame 60. Has a seal structure.

The sealing structure of the electrolyte passage hole is simple, and the outer periphery of the center hole of the ring spacer 62 is brought into contact with the synthetic resin frame 60 via the O-ring 63 to form a continuous passage depending on the number of laminated layers. However, during press lamination, it is integrated with the synthetic resin frame 60 and a completely sealed structure is obtained, and even if electrolyte solution such as sulfuric acid flows into or out of the electrolyte layer through the passage hole, there will be no external leakage. Almost never occurs.

In addition, the passage holes 10 to 13 for distributing glass and the cooling medium passage holes 14 and 15 have the same sealing structure. Taking the anode gas passage hole 10 on the supply side as an example, as shown in FIG. A ring-shaped retainer sealing material a made of synthetic resin with an elastic seal b disposed on the inner circumferential surface between the stacked adjacent metal frame laminates 1
It has a sealing structure in which the retainer seal material a holds an elastic seal b which becomes thinner during press lamination.

In the above seal structure, the ring-shaped retainer seal material a serves as a spacer equivalent to the thickness of the synthetic resin frame 60 and the two electrode plates 7 between the metal frame laminate 1, and is arranged on the inner peripheral surface of the ring-shaped retainer seal material a. An elastic seal b made of synthetic resin forms a sealed passage hole 10 by coming into close contact with the metal frame laminate 1 and the ring-shaped retainer seal material a during press lamination,
There is no leakage of gas or cooling medium.

Furthermore, the cooling passage frame 20 occupying the central part of the metal frame laminate 1 has corner parts 22 at the four corners of the opening in which the corrugated fins 23 are built, and projections 21 for providing gas passage holes. , forming a sealed passage communicating with the gas passage hole.

That is, each protrusion 21 has a gas passage hole 10.
- 13 are perforated, and connected to these are oval-shaped sealed passage holes, and when laminated, sealed passages 24 to 27 are formed with the partition plate 5.

For example, the anode gas from the anode gas passage hole 10 on the supply side enters the sealed passage 24 provided in the cooling passage 2, passes through the hole 51 of the partition plate 5,
It enters the anode gas passage 3 of the gas passage frame 30.

The anode gas that has descended in the anode gas passage 3 enters the sealed passage 25 in the cooling passage 2 through the hole 52 below the partition plate 5, and further flows out through the anode gas passage hole 11. Similarly, in the case of the cathode gas passage hole 12, the cathode gas enters the sealed passage 26 provided in the cooling passage 2, and enters the hole 53 of the partition plate 5.
The cathode gas enters the cathode gas passage 4 of the gas passage frame 40 and descends inside the cathode gas passage 4. The cathode gas enters the sealed passage 27 in the cooling passage 2 through the hole 54 below the partition plate 5, and then enters the cathode gas passage 4. The gas flows out through the gas passage hole 13.

Further, the cooling medium is passed through the cooling medium passage hole 14 formed in the horizontally protruding protrusion 21 of the cooling passage frame 20, through the communication passage 28 communicating therewith, and into the cooling passage formed by the corrugated fins 23. 2
The cooling medium enters the cooling medium passage hole 15 on the outflow side through the communication passage 29 provided in the protrusion 21 on the opposite side of the frame 20, and flows out to the outside.

The corrugated fins 23, 33, 43 in the metal frames 20, 30, 40 are provided with a large number of slits or small holes that communicate in the corrugated direction.
The fluid can pass in the vertical direction, and as described above, in the cooling passage 2, the cooling medium flows horizontally, and in the anode gas passage 3 and the cathode gas passage 4, each gas flows in the diagonal direction of the opening of the frame. The fluids flow crosswise from the upper side to the lower side, and each fluid passes through the passage uniformly and smoothly.

In the metal frame laminate 1, the frame, corrugated fins, and partition plates are all made of aluminum composite, and because they are integrally joined by brazing, the heat conduction efficiency is high and uniform, and there is no need for gas passages 3 and 4. The heat is immediately transferred to the cooling medium in the cooling passage 2 by the metal frame laminate 1, and as the cooling medium circulates, the heat is radiated to the outside.

In the stacked fuel cell according to the present invention, the cooling medium passage and the anode gas and cathode gas passages are constructed of a laminated plate-fin type heat exchanger structure formed by integrally brazing a metal frame with built-in corrugated fins. As a result, the heat generated by the electrochemical reaction is transferred from the anode gas and cathode gas passages through the corrugated fins.
The heat is immediately transmitted to the corrugated fins of the cooling passage, which are integrated by brazing, and is radiated through the cooling medium.

In addition, in this cooling structure, heat is radiated through corrugated fins with excellent heat exchange efficiency, so the temperature distribution is uniform.Also, by making the laminated metal frames integrally joined by brazing, the heat at the joint is This has the advantage of providing a fuel cell cooling structure with extremely low resistance and extremely high heat dissipation effect.

In addition, the cooling structure according to the present invention has a metal frame laminate with an integral laminated structure by brazing, and in combination with the above-mentioned seal structure, it has excellent sealing performance for each fluid, and the anode gas and cathode gas are connected to the coil gate. It has the advantage of uniform distribution with fins, and furthermore, the gas passage uses a metal frame in the stacking direction, and the distribution inlet is provided in the cooling passage, which greatly contributes to making the fuel cell smaller and lighter. The configuration is as follows.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a fuel cell showing a laminated seal structure of an electrolyte distribution passage hole according to the present invention. FIG. 2 is a longitudinal cross-sectional view of a fuel cell showing a laminated seal structure of a reactive gas distribution passage hole according to the present invention. FIG. 3 is a front view and a cross-sectional explanatory view of a metal frame laminate showing a cooling passage structure according to the present invention. FIG. 4 is a front explanatory view of the synthetic resin frame,
FIG. 5 is an explanatory front view of the metal frame. FIGS. 6 and 7 are a front view and a side view of a fuel cell using the cooling passage structure according to the present invention. 1... Metal frame laminate, 2... Cooling passage, 3, 4
... Gas passage, 5 ... Partition plate, 6 ... Electrolyte layer,
7... Electrode plate, 8... Bolt, 9... Header plate, 10-17... Passage hole, 18... Connector, 20... Cooling passage frame, 21, 31, 41...
Projection, 22... corner, 23, 33, 43... corrugated fin, 24-27... sealed passage, 2
8, 29...Communication passage, 30, 40...Gas passage frame, 51-54...Small hole, 60...Synthetic resin frame,
61... Protrusion, 62... Ring-shaped spacer, a
...Ring-shaped retainer sealing material, b...Elastic seal.

Claims (1)

[Claims] 1 A metal frame stacked structure in which three passage bodies each having heat transfer fins built in a thin metal frame are stacked with a partition plate interposed therebetween, with the intermediate passage body serving as a cooling medium passage and both sides serving as anode gas or cathode gas passages. , consists of a stack of multiple sets of battery cells in which an electrolyte frame made of synthetic resin is sandwiched between electrode plates and an anode and a cathode are arranged, and a passage hole is formed in the metal frame and arranged coaxially when stacking the electrolyte, It has a structure in which the anode gas or cathode gas communicates with the gas distribution passage and passes through a sealed passage provided in the cooling medium passage when the anode gas or cathode gas flows in or out. A ring spacer made of synthetic resin having a length between the frames is fitted into the electrolyte liquid passage hole and brought into contact with the synthetic resin frame via an O-ring to form an electrolyte liquid passage hole, and the electrolyte liquid is made of synthetic resin. It has a seal structure that allows flow into and out of the electrolyte layer in the synthetic resin frame between the electrode plates from the small hole communicating with the hole in the frame. A ring-shaped retainer seal made of synthetic resin having an elastic sealing material arranged on the inner circumferential surface is interposed between the metal frame laminates, and the retainer sealing material holds the elastic seal that becomes thinner when laminated under pressure. A fuel cell characterized by having a seal structure.