TWI586027B - Fuel cell stack unit - Google Patents

Description

Fuel cell stack unit

The present invention relates to a fuel cell stack unit, and more particularly to a flat type solid oxide fuel cell stack unit.

The fuel cell converts the chemical energy in the fuel into electrical energy, which can provide stable power without charging or replacing. The solid oxide fuel cell (SOFC) can be simply connected to the fuel cell stack by stacking. The unit improves the output of electric energy and has the advantages of long-term stability and low cost, so it is favored in various application fields.

However, the existing fuel cell stack unit tends to affect the fuel flow due to deformation of the sealing material during packaging, or the sealing material is likely to act or dissolve due to contact with the fuel, thereby affecting the power generation efficiency and stability of the SOFC. In addition, the power density, fuel utilization rate, and power generation efficiency of the existing fuel cell stack unit also have room for improvement.

Accordingly, it is an object of the present invention to provide a fuel cell stack unit that overcomes the above-discussed shortcomings of the prior art.

Therefore, the fuel cell stack unit of the present invention comprises two bipolar plates, a membrane electrode assembly (MEA), an anode separation module and a cathode separation module. Each bipolar plate includes an anode side and a cathode side disposed opposite the anode side. The anode side has a set of fluid fuel inlet channels, a set of fluid fuel outlet channels, and a fluid fuel flow field communicating the set of fluid fuel inlet channels and the set of fluid fuel outlet channels (flow field). The cathode side has a set of oxygen-containing fluid inlet flow passages, a set of oxygen-containing fluid outlet flow passages, and an oxygen-containing fluid flow field connecting the set of oxygen-containing fluid inlet flow passages and the set of oxygen-containing fluid outlet flow passages. The membrane electrode assembly is disposed between the two bipolar plates, and includes: an anode metal mesh disposed corresponding to the fluid fuel flow field, a cathode metal mesh disposed corresponding to the oxygen-containing fluid flow field, and a cathode metal mesh disposed at the anode An electrolyte membrane between the metal mesh and the cathode metal mesh, the boundary of the anode metal mesh being defined by the electrolyte membrane, the fluid fuel flow field and an anode sealing region, the cathode metal The boundary of the mesh is defined by the electrolyte membrane, the oxygen-containing fluid flow field and a cathode sealing zone. The anode separation module is disposed on the anode side of the bipolar plate to sealingly separate the set of fluid fuel inlet flow channels from the anode sealing zone and sealingly separate the set of fluid fuel outlet flow channels from the anode sealing zone. The cathode separation module is disposed on the cathode side of the bipolar plate to sealingly separate the set of oxygen-containing fluid inlet flow channels from the cathode sealing zone, and sealingly separates the set of oxygen-containing fluid outlet flow channels from the cathode seal Area.

The invention has the effect that the fuel cell stack unit can prevent the sealing regions from being deformed during packaging to affect the flow of the fluid, and can prevent the fluid from interacting with or dissolving the materials of the sealing regions.

The contents of the present invention will be described in detail below:

Preferably, the anode separation module is detachably embedded in the set of fluid fuel inlet flow channels and the set of fluid fuel outlet flow channels, and the cathode separation module is detachably embedded in the group of oxygen a fluid inlet flow passage and the set of oxygen-containing fluid outlet flow passages.

Optionally, the two bipolar plates, the anode separation module and the cathode separation module are single pieces.

Preferably, the flow path cross-sectional area of the set of fluid fuel inlet flow passages communicating with the fluid fuel flow flow passage is greater than the flow passage cross-sectional area of the set of fluid fuel outlet flow passages communicating with the fluid fuel flow flow passage.

Preferably, the anode separation module is in the same plane as the fluid fuel flow field, and the cathode separation module is in the same plane as the oxygen-containing fluid flow field.

Preferably, the set of fluid fuel inlet flow passages and the set of fluid fuel outlet flow passages are mutually corresponding linear flow passages, and the set of oxygen-containing fluid inlet flow passages and the set of oxygen-containing fluid outlet flow passages correspond to each other in a straight line type The flow path is used to control the direction of fluid flow and has a rectifying effect. More preferably, the set of fluid fuel inlet flow passages and the set of fluid fuel outlet flow passages are respectively located on two opposite sides of the fluid fuel flow field, and the set of oxygen-containing fluid inlet flow passages and the set of oxygen-containing fluid outlet flow passages are respectively Located on two opposite sides of the oxygen-containing fluid flow field. Still more preferably, the set of fluid fuel inlet flow passages and the set of fluid fuel outlet flow passages extend perpendicularly to the set of oxygen-containing fluid inlet flow passages and the direction in which the set of oxygen-containing fluid outlet flow passages extend.

Preferably, the fluid fuel flow field and the oxygen-containing fluid flow field respectively have a column array arranged in a checkerboard shape to respectively form a mesh network.

Preferably, the material of the anode sealing zone and the cathode sealing zone is selected from glass ceramics, mica or solder alloy to insulate the anode metal mesh and the cathode metal mesh, respectively.

Preferably, the material of the two bipolar plates, the anode separation module and the cathode separation module is stainless steel, such as, but not limited to, SUS 430, SUS 431, SUS 441, and Crofer® 22.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same reference numerals.

The invention is further described in the following examples, but it should be understood that these examples are for illustrative purposes only and are not to be construed as limiting.

Referring to FIG. 1 to FIG. 3, a first embodiment of a flat type solid oxide fuel cell stack unit 1 of the present invention comprises two bipolar plates 2, a membrane electrode assembly 3, an anode separation module 4 and a cathode separation module. 5.

Each bipolar plate 2 includes an anode side 24 and a cathode side 25 disposed opposite the anode side 24.

The anode side 24 has a set of fluid fuel inlet runners 241, a set of fluid fuel outlet runners 242 (see FIG. 7), and a fluid fuel that communicates the set of fluid fuel inlet runners 241 with the set of fluid fuel outlet runners 242. Flow field 243 (see Figure 7). The set of fluid fuel inlet flow passages 241 and the set of fluid fuel outlet flow passages 242 are mutually corresponding linear flow passages and are located on opposite sides of the fluid fuel flow field 243, respectively. The fluid fuel flow field 243 has an anode stud array 248 (see Fig. 7) arranged in a checkerboard shape to form a grid-shaped anode runner network 249 (see Fig. 7).

The cathode side 25 has a set of oxygen-containing fluid inlet channels 251, a set of oxygen-containing fluid outlet channels 252, and an oxygen-containing fluid connecting the set of oxygen-containing fluid inlet channels 251 and the set of oxygen-containing fluid outlet channels 252. Flow field 253. The set of oxygen-containing fluid inlet flow passages 251 and the set of oxygen-containing fluid outlet flow passages 252 are linear flow passages corresponding to each other, and are respectively located at two opposite sides of the oxygen-containing fluid flow field 253. The oxygen-containing fluid flow field 253 has a cathode stud array 258 (see Fig. 6) arranged in a checkerboard shape to form a grid-like cathode runner network 259 (see Fig. 6).

The set of fluid fuel inlet runners 241 and the set of fluid fuel outlet runners 242 extend perpendicularly to the direction in which the set of oxygenated fluid inlet runners 251 and the set of oxygenated fluid outlet runners 252 extend.

The membrane electrode assembly 3 is disposed between the two bipolar plates 2, and includes: an anode metal mesh 34 disposed corresponding to the fluid fuel flow field 243, and a cathode metal mesh 35 disposed corresponding to the oxygen-containing fluid flow field 253. And a solid oxide electrolyte membrane 33 disposed between the anode metal mesh 34 and the cathode metal mesh 35, the anode metal mesh 34 is bordered by the electrolyte membrane 33, the fluid fuel flow field 243 and an anode sealing zone 36 is collectively defined, the boundary of the cathode metal mesh 35 is defined by the electrolyte membrane 33, the oxygen-containing fluid flow field 253 and a cathode sealing zone 37.

In the first embodiment, the anode sealing region 36 and the cathode sealing region 37 are made of glass ceramic to insulate the anode metal mesh 34 and the cathode metal mesh 35, respectively.

Referring to FIGS. 2 to 4 , the anode separation module 4 is disposed on the anode side 24 of the bipolar plate 2 and is detachably embedded in the set of fluid fuel inlet flow passages 241 and the set of fluid fuel outlet passages 242 . (See FIG. 7) and in the same plane as the fluid fuel flow field 243 to sealingly separate the set of fluid fuel inlet runners 241 from the anode seal zone 36 and sealingly separate the set of fluid fuel outlet runners 242 And the anode sealing zone 36, so that the anode sealing zone 36 is evenly stressed when the fuel cell stack unit 1 is packaged, and is not deformed with the set of fluid fuel inlet flow passages 241 and the set of fluid fuel outlet flow passages 242. And the fluid fuel in the set of fluid fuel inlet flow passages 241 and the set of fluid fuel outlet flow passages 242 can be prevented from acting or dissolving the material of the anode sealing zone 36.

Referring to FIG. 1 to FIG. 3, the cathode separation module 5 is disposed on the cathode side 25 of the bipolar plate 2, and is detachably embedded in the set of oxygen-containing fluid inlet flow passages 251 and the set of oxygen-containing fluid outlet flows. Lane 252 and in the same plane as the oxygen-containing fluid flow field 253 to sealingly separate the set of oxygen-containing fluid inlet flow passages 251 from the cathode seal region 37 and sealingly separate the set of oxygen-containing fluid outlet passages 252 And the cathode sealing zone 37, so that the cathode sealing zone 37 is evenly stressed when the fuel cell stack unit 1 is packaged, so as not to follow the set of oxygen-containing fluid inlet flow channels 251 and the set of oxygen-containing fluid outlet flow channels 252. The deformation and the oxygen-containing fluid inlet flow passage 251 and the oxygen-containing fluid in the set of oxygen-containing fluid outlet passages 252 are prevented from acting or dissolving with the material of the cathode sealing zone 37.

In the first embodiment, the flow path cross-sectional area (about 22.1 mm ² ) at which the set of fluid fuel inlet runners 241 communicate with the fluid fuel flow field 243 is greater than the set of fluid fuel outlet runners 242 and the fluid The cross-sectional area of the flow path at the junction of the fuel flow field 243 (approximately 13.26 mm ² ).

In the first embodiment, the material of the two bipolar plates 2 is stainless steel, and the anode separation module 4 and the cathode separation module 5 are each two stainless steel sheets, which are resistant to high temperature and have good electrical conductivity at high temperatures. .

Referring to FIGS. 5-7, when the fuel cell stack unit 1 performs power generation, a fluid fuel flows into the fluid fuel flow field 243 from the set of fluid fuel inlet channels 241, and is evenly distributed by the anode stud array 248. Flowing through the anode metal mesh 34, an oxidation reaction occurs in the electrolyte membrane 33, and the remaining fluid fuel flows out of the set of fluid fuel outlet flow passages 242; meanwhile, an oxygen-containing fluid flows into the oxygen-containing fluid inlet flow passage 251. The oxygen-containing fluid flow field 253 is uniformly distributed by the cathode stud array 258, flows through the cathode metal mesh 35, and a reduction reaction occurs in the electrolyte membrane 33, and the remaining oxygen-containing fluid is discharged from the oxygen-containing fluid outlet flow path. 252 outflow.

A second embodiment of a fuel cell stack unit 1 of the present invention is similar to the first embodiment in that the set of fluid fuel inlet flow passages 241 are in communication with the fluid fuel flow field 243 in the second embodiment. The cross-sectional area of the flow path is equal to the cross-sectional area of the flow path at which the set of fluid fuel outlet flow passages 242 communicate with the fluid fuel flow field 243 (both about 22.1 mm ² ).

a hydrogen-nitrogen mixed gas (containing 3% water vapor) is introduced from the set of fluid fuel inlet flow passages 241 of the first embodiment and the fuel cell stack unit 1 (single layer) of the second embodiment, respectively, and The oxygen-containing fluid inlet flow passage 251 is passed through dry air for 100 hours, and the maximum power density is measured using an electronic load [setting load current of 32.4 A and operating voltage of 0.6 to 0.7 V]. (650 ° C), fuel utilization rate and power generation efficiency (test temperature 620 ° C), the results are shown in Table 1 below. 【Table 1】         <TABLE border="1" borderColor="#000000" width="_0003"><TBODY><tr><td> </td><td> Maximum Power Density</td><td> Fuel Utilization </ Td><td> power generation efficiency</td></tr><tr><td> Example 1 </td><td> 0.643 W/cm²</td><td> 71.69% </td><td> 38.37% </td></tr><tr><td> Example 2 </td><td> 0.602 W/cm²</td ><td> 67.71% </td><td> 36.18% </td></tr></TBODY></TABLE>

As can be seen from the above Table 1, the maximum power density, fuel utilization rate and power generation efficiency of the first embodiment are greater than that of the second embodiment, showing that the fluid fuel of the first embodiment is in its fluid fuel flow field 243. Flow uniformity is preferred.

In summary, the fuel cell stack unit 1 of the present invention sealingly separates the flow channels 241, 242, 251, 252 and the anode separation module 4 and the cathode separation module 5 disposed on the bipolar plate 2 The sealing regions 36, 37 can uniformly load the sealing regions 36, 37 during packaging, affecting the flow of the fluid fuel and the oxygen-containing fluid without deformation, and avoiding the flow passages 241, 242, 251, The fluid fuel and oxygen-containing fluid in 252 interact with or dissolve the materials of the seal regions 36, 37, so that the object of the present invention can be achieved.

However, the above is only the embodiment of the present invention, and the scope of the invention is not limited thereto, and all the equivalent equivalent changes and modifications according to the scope of the patent application and the patent specification of the present invention are still The scope of the invention is covered.

1‧‧‧fuel cell stack unit
2‧‧‧ bipolar plates
24‧‧‧ anode side
241‧‧‧Fluid fuel inlet runner
242‧‧‧Fluid fuel outlet runner
243‧‧‧Fluid fuel flow field
248‧‧‧Anode column array
249‧‧‧Anode flow channel network
25‧‧‧ Cathode side
251‧‧‧Oxygen fluid inlet runner
252‧‧‧Oxygen-containing fluid outlet flow path
253‧‧‧Oxygen-containing fluid flow field
258‧‧‧cathode pillar array
259‧‧‧Cathodic flow channel network
3‧‧‧ membrane electrode group
33‧‧‧ electrolyte membrane
34‧‧‧Anode metal mesh
35‧‧‧Cathed metal mesh
36‧‧‧Anode sealing area
37‧‧‧Cathodic sealing area
4‧‧‧Anode separation module
5‧‧‧Cathode separation module

Other features and effects of the present invention will be apparent from the following description of the drawings, wherein: FIG. 1 is a perspective view of a first embodiment of the fuel cell stack unit of the present invention; [FIG. 2] An exploded perspective view of the first embodiment; [Fig. 3] is an exploded perspective view of a bipolar plate, an anode separation module and a cathode separation module of the first embodiment; [Fig. 4] A cross-sectional view taken along line IV-IV in FIG. 1; [FIG. 5] is a cross-sectional view taken along line V-V in FIG. 1; [FIG. 6] is the first embodiment. A top view of the bipolar plate, the anode separation module and the cathode separation module; and [FIG. 7] is the bipolar plate, the anode separation module and the cathode separation module of the first embodiment Looking up at the schematic.

1‧‧‧fuel cell stack unit

2‧‧‧ bipolar plates

24‧‧‧ anode side

25‧‧‧ Cathode side

253‧‧‧Oxygen-containing fluid flow field

3‧‧‧ membrane electrode group

33‧‧‧ electrolyte membrane

34‧‧‧Anode metal mesh

35‧‧‧Cathed metal mesh

36‧‧‧Anode sealing area

37‧‧‧Cathodic sealing area

4‧‧‧Anode separation module

5‧‧‧Cathode separation module

Claims (10)

A fuel cell stack unit comprising: two bipolar plates, each bipolar plate comprising: an anode side having a set of fluid fuel inlet flow channels, a set of fluid fuel outlet flow channels, and a communication fluid flow inlet passageway a fluid fuel flow field with the set of fluid fuel outlet passages, and a cathode side disposed opposite the anode side, having a set of oxygen-containing fluid inlet flow passages, a set of oxygen-containing fluid outlet flow passages, and a connection group An oxygen-containing fluid flow field and an oxygen-containing fluid flow field of the set of oxygen-containing fluid outlet channels; a membrane electrode group disposed between the two bipolar plates, comprising: an anode metal corresponding to the fluid fuel flow field a mesh, a cathode metal mesh corresponding to the flow field of the oxygen-containing fluid, and an electrolyte membrane disposed between the anode metal mesh and the cathode metal mesh, the boundary of the anode metal mesh being the electrolyte membrane, the fluid fuel The flow field is defined together with an anode sealing zone, and the boundary of the cathode metal mesh is defined by the electrolyte membrane, the oxygen-containing fluid flow field and a cathode sealing zone; an anode separation module is disposed on The anode side of the bipolar plate sealingly partitions the set of fluid fuel inlet flow channels from the anode sealing zone and sealingly separates the set of fluid fuel outlet flow channels from the anode sealing zone; and a cathode separation module is disposed On the cathode side of the bipolar plate, the set of oxygen-containing fluid inlet flow channels and the cathode sealing zone are sealingly separated, and the set of oxygen-containing fluid outlet flow channels and the cathode sealing zone are sealingly separated. The fuel cell stack unit of claim 1, wherein the anode separation module is detachably embedded in the set of fluid fuel inlet flow channels and the set of fluid fuel outlet flow channels, the cathode separation module is The detached ground is embedded in the set of oxygen-containing fluid inlet flow channels and the set of oxygen-containing fluid outlet flow channels. The fuel cell stack unit of claim 1, wherein a cross-sectional area of the flow path of the set of fluid fuel inlet flow passages communicating with the fluid fuel flow field is greater than a flow of the set of fluid fuel outlet flow passages communicating with the fluid fuel flow field The cross-sectional area of the runner. The fuel cell stack unit of claim 1, wherein the anode separation module is in the same plane as the fluid fuel flow field, and the cathode separation module is in the same plane as the oxygen-containing fluid flow field. The fuel cell stack unit of claim 1, wherein the set of fluid fuel inlet flow passages and the set of fluid fuel outlet flow passages are mutually corresponding linear flow passages, the set of oxygen-containing fluid inlet flow passages and the set of A linear flow path in which the oxygen fluid outlet flow paths correspond to each other. The fuel cell stack unit of claim 5, wherein the set of fluid fuel inlet flow passages and the set of fluid fuel outlet flow passages are respectively located on opposite sides of the fluid fuel flow field, the set of oxygen-containing fluid inlet flow passages And the set of oxygen-containing fluid outlet flow channels are respectively located on opposite sides of the oxygen-containing fluid flow field. The fuel cell stack unit of claim 6, wherein the set of fluid fuel inlet flow channels and the set of fluid fuel outlet flow paths extend perpendicular to the set of oxygen-containing fluid inlet flow channels and the set of oxygen-containing fluid outlet flows The direction of the road. The fuel cell stack unit according to claim 1, wherein the fluid fuel flow field and the oxygen-containing fluid flow field respectively have a column array arranged in a checkerboard shape to respectively form a grid-like flow channel network. . The fuel cell stack unit of claim 1, wherein the material of the anode sealing zone and the cathode sealing zone is selected from the group consisting of glass ceramics, mica or solder alloy. The fuel cell stack unit of claim 1, wherein the material of the two bipolar plates, the anode separation module and the cathode separation module is stainless steel.