JP2000353531A - Separator for solid high polymer fuel cell and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a separator for a solid high polymer fuel cell having favorable corrosion resistance and manufacturable at comparatively low cost. SOLUTION: This separator 20 having a passage 25 for supplying an oxidizing agent or fuel to a positive electrode or a negative electrode laminated on a high polymer electrolyte film is provided with a metallic material layer 21 and a protective layer 22 covering the metallic material layer 21. The protective layer 22 contains a metal nitride and an N content in the protective layer 22 decreases as it goes from the surface to the interior of the protective layer 22. Preferably, the metal nitride is a nitride of Ti or Cr.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell separator and a method for producing the same, and more particularly to a separator used for a solid polymer electrolyte fuel cell (PEFC), which is a solid electrolyte fuel cell having a polymer electrolyte membrane. It relates to the manufacturing method.

[0002]

2. Description of the Related Art A polymer electrolyte fuel cell using hydrogen gas as fuel and oxygen gas as oxidant has a cell structure as shown in FIG. 1, for example. In the cell 10, on both sides of the polymer electrolyte membrane 11, a negative electrode (hydrogen electrode) provided with a catalyst.
12 and a positive electrode (oxygen electrode) 13 are provided, and separators 14 and 15 are provided so as to sandwich them. Each of the separators 14 and 15 has a hydrogen supply passage (groove) 16 and an oxygen supply passage (groove) 17. The hydrogen gas and the oxygen gas are guided from outside to the passages 16 and 17 through supply holes (not shown), respectively.
These are supplied to the negative electrode 12 and the positive electrode 13, respectively. The negative electrode side, a reaction occurs that shown by the following ^{_{formula, H 2 → 2H + + 2e}} - at the cathode, a reaction occurs indicated by the following ^{_{equation, 1 / 2O 2 + 2H +}} + 2e - → H 2 O Total reaction, the table by the following formula Is done. H ₂ + ／ O ₂ → H ₂ O As shown above, since H ⁺ is generated in the negative electrode, the separator needs to have acid resistance. Further, since the separator is exposed to oxygen on the positive electrode side, it needs to have oxidation resistance. Thus, corrosion resistance is required for the separator. Furthermore, in order to keep the internal resistance of the fuel cell low, it is desirable that the electrical resistance of the separator be low.
In addition, accuracy of dimensions (especially thickness), flatness (less warpage), airtightness (prevention of gas permeation), workability, strength,
Light weight, low cost, etc. are required for the separator.

[0003] Conventionally, graphite has been considered to be a prominent material for separators for polymer electrolyte fuel cells. However, graphite has the following disadvantages. Since the graphite separator is formed by cutting, the processing cost is relatively high, and there is a limit in reducing the cost to some extent. In a fuel cell mounted on a vehicle such as an automobile, low cost is one of the most important issues, and a graphite separator is disadvantageous in this regard. Also, graphite is brittle,
Therefore, there is a concern that cracks may occur in applications that are frequently subject to vibration, for example, in a fuel cell mounted on a vehicle such as an automobile. Graphite is also disadvantageous in terms of durability.

[0004] On the other hand, ordinary metal materials have workability, strength,
Although advantageous in terms of cost, it is inferior in corrosion resistance and its electric resistance increases during use, deteriorating the characteristics of the fuel cell.

[0005]

SUMMARY OF THE INVENTION One object of the present invention is to provide a polymer electrolyte fuel cell separator having the following points in view of the above-mentioned problems in the prior art. (1) Good corrosion resistance. (2) Changes in electrical resistance during use are small. (3) Good workability. (4) Low cost. (5) High fatigue strength and good durability.

[0006]

A separator according to the present invention is a separator having a passage for supplying an oxidizing agent or fuel to a positive electrode or a negative electrode laminated on a polymer electrolyte membrane, comprising a metal material layer and a metal material layer. A protective layer covering the material layer. The protective layer contains a metal nitride, and the N content in the protective layer decreases from the surface to the inside of the protective layer.

In the separator according to the present invention, the metal nitride is Ti, Ti alloy, Cr, Cr alloy, Zr, Zr
Alloy, Hf, Hf alloy, V, V alloy, Nb, Nb alloy,
At least one selected from the group consisting of Ta and nitrides of Ta alloys can be used.

[0008] In the separator according to the present invention, the metal material is Fe, Fe alloy, Ni, Ni alloy, Cr, Cr alloy, Cu, Cu alloy, Al, Al alloy, Ti and Ti.
At least one selected from the group consisting of alloys can be used.

In one preferred embodiment, the metal nitride is a nitride of Ti, and the protective layer contains at least one of TiN and Ti ₂ N as the nitride of Ti.
In another preferred embodiment, the metal nitride is Cr
And the protective layer is made of C
at least one selected from the group consisting of rN, Cr ₂ N, CrN ₂ and Cr (N ₃ ) ₃ .

According to the present invention, it is possible to provide a separator in which the metal material is made of titanium and the protective layer is formed by nitriding the titanium.

Further, according to the present invention, the metal material includes the first metal, the metal nitride is a second metal nitride different from the first metal, and the metal nitride is the first metal. A separator formed by nitriding a second metal deposited on a metal can be provided. In this case, the first metal can be stainless steel,
Further, the second metal can be at least one selected from the group consisting of Ti, Ti alloy, Cr, and Cr alloy. Alternatively, the first metal can be aluminum and the second metal is Ti, Ti alloy, Cr
And at least one selected from the group consisting of Cr alloys.

One manufacturing method according to the present invention is a method for manufacturing a separator having a passage for supplying an oxidant or a fuel to a positive electrode or a negative electrode laminated on a polymer electrolyte membrane, wherein the separator has a shape having at least a passage. The method includes a step of processing a metal plate and a step of nitriding a surface of the processed metal plate.

In a preferred production method according to the invention,
The metal plate is made of Ti or a Ti alloy.

Another manufacturing method according to the present invention is a method of forming a Ti, Ti alloy, Cr, Cr alloy, Zr, Zr alloy, Hf, Hf alloy, V, V alloy, Nb, Nb alloy, Tb alloy on a metal plate.
at least one selected from the group consisting of a and a Ta alloy
A step of depositing a seed metal and a step of nitriding the deposited metal. In this case, a metal plate processed to have at least a passage for supplying a fuel or an oxidant may be used in the deposition step.On the other hand, after the deposition step, the metal plate is formed into a shape having at least a passage. It may be processed.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The separator according to the present invention uses a metal as a base. Metal can be processed with high precision by plastic working or the like, and contributes to cost reduction. In the present invention, this metal is covered with a protective layer containing a metal nitride. The nitride contributes to the corrosion resistance of the separator,
Effectively prevents the electrical resistance from rising during use. In the protective layer of the separator according to the invention, the N content (or N
(Concentration) decreases from the surface to the inside of the protective layer. That is, in the protective layer, the content or concentration of the metal nitride decreases from the surface to the inside. The protective layer having such a composition has good adhesion to the underlying metal and is difficult to peel off from the underlying layer. In addition, the protective film in which a rapid change in composition is suppressed has high fatigue strength, is less likely to crack during use, and has good durability.

FIG. 2 shows an example of a sectional structure of the separator according to the present invention. In the separator 20 having the passage 25 for the fuel gas or the oxidizing gas, the metal material layer 2
1 is covered with a protective layer 22 mainly composed of a metal nitride. In the protective layer 22, the content or concentration of N or nitride may be gradually reduced as shown in FIG. 3A, or may be continuously (monotonously) as shown in FIG. 3B. It may decrease. Specifically, the protective layer 22 is a so-called gradient composition film. In a preferred embodiment, the N or nitride content is highest at the outermost surface of the protective layer. In a preferred embodiment, substantially the entire metal is nitrided on the outermost surface of the protective layer, while a composite layer of nitride and metal is formed inside the protective layer 22 and the metal material layer 2.
In the first boundary region, almost no nitride is contained. In the composite material layer, the concentration or volume ratio of the nitride decreases toward the inside, and the concentration or volume ratio of the metal increases toward the inside.

The metal species contained in the protective layer 22 and the metal species contained in the metal material layer 21 may be the same or different. When both are the same, a protective layer can be obtained by nitriding the prepared metal material from its surface. If the two are different, for example, a protective layer can be obtained by depositing another metal on the prepared metal material and nitriding the deposited metal. Fig. 4 shows the same example.
Shown in In the separator 40 shown in FIG. 4, the metal material layer 41 is made of Ti. The protective layer 42 is mainly composed of Ti nitride (TiN, Ti ₂ N), and its surface is occupied by Ti nitride, particularly TiN, while the inside is made of a composite of Ti nitride and Ti. Yes, the N content decreases as it goes inside. On the front and back surfaces of the separator 40, passages 45a for fuel and oxidant are respectively provided.
And 45b are formed. Fig. 5 shows an example where the two are different.
Shown in In the separator 50 shown in FIG. 5, the metal material layer 51 is made of aluminum or stainless steel.
The protective layer 52 is made of Ti nitride (TiN, Ti ₂ N) or Cr nitride (CrN, Cr ₂ N, CrN ₂ , Cr (N
₃ ) The main component is ₃ ), the surface of which is occupied by nitride, while the inside is a composite of nitride and Ti or Cr, and the N content decreases toward the inside. Passages 55a and 55b for the fuel and the oxidant are formed on the front and back surfaces of the separator 50, respectively.

Further, in the separator according to the present invention,
The metal material layer may be composed of one kind of metal material,
It may be made of more than one kind of metal material. FIG. 6 shows an example in which a plurality of types of metal materials are used. In the separator 60, the second metal material 61b is overlaid on the first metal material 61a. The second metal material 61b is covered with a protective layer 62 containing nitride. For example, the first metal material can be Al or Ti and the second metal material can be stainless steel.

In the separator according to the present invention, the metal material layer preferably has an electric resistance of 10 ⁻⁴ Ω · cm or less, more preferably 10 ⁻⁵ Ω · cm or less. The metal material is, for example, Fe, Fe alloy, Ni, Ni alloy, C
r, Cr alloy, Cu, Cu alloy, Al, Al alloy, Ti
And Ti alloys. The thickness of the metal material layer can be from 0.2 to 2.0 mm, and preferably from 0.5 to 1.0 mm. The nitride of the protective layer is, for example, Ti, Ti alloy, C
r, Cr alloy, Zr, Zr alloy, Hf, Hf alloy, V,
It can be selected from the group consisting of V alloy, Nb, Nb alloy, Ta and nitride of Ta alloy. In particular, a nitride having a low electric resistance is preferable, a nitride having an electric resistance of 10 to 1000 × 10 ⁻⁶ is preferable, and a nitride having an electric resistance of 10 to 500 × 10 ⁻⁶ is more preferable. From the viewpoints of corrosion resistance, low electric resistance, and low film formation cost, nitrides of Ti (the electric resistance of TiN is 22 to 130 × 10 ⁻⁶ ) and C
The nitride of r (Cr has an electrical resistance of 640 × 10 ⁻⁶ ) is more preferable. The thickness of the protective layer containing nitride is 3 to 500 μm.
m, and preferably 5 to 50 μm.

The separator according to the present invention can be manufactured, for example, by a method as shown in FIGS. 7 (a) to 7 (c). First, as shown in FIG. 7A, a metal plate 71 having other shapes (not shown) such as a groove 75 serving as a flow path for a fuel or an oxidant and, if necessary, a hole is prepared. A required shape such as a groove can be obtained by pressing a metal plate. Next, the distortion is removed by heat treatment or the like as necessary, and the oxide film covering the surface of the metal plate is removed by plasma etching or the like as necessary. Next, as shown in FIG.
First, a nitriding treatment is performed from the clean surface. The nitriding treatment can be performed by various nitriding methods such as heating in a nitrogen atmosphere and plasma nitriding. In particular, the plasma nitriding method is more effective than the nitriding method using an ammonia decomposition gas or a cyanide compound.
This is advantageous in that a dense nitride film can be formed. In the plasma nitriding method, for example, in a nitrogen mixed gas atmosphere of 0.1 to 10 Torr, a furnace body is used as an anode, an object to be processed is used as a cathode, and a DC voltage of several hundred volts is applied between both electrodes. As a result, a glow discharge occurs, and soft light resembling a neon sign covers the object to be processed. At that time, the ionized gas component is accelerated at a high speed, collides with the object to be processed, and is heated and sputtered. , Nitriding proceeds. For the nitrogen mixed atmosphere, for example, a composition of N ₂ : H ₃ : CO ₂ = 1: 1: 0.07 is used.
00 ° C. As a result of the nitriding treatment, the surface of the metal plate 71 is nitrided, and as shown in FIG. 7C, a protective film 72 mainly composed of a metal nitride is formed.

FIG. 8 shows a separator according to the present invention.
It may be manufactured by a method as shown in (a) to (d). First, as shown in FIG. 8A, a metal plate 81 having a flat surface is prepared. Next, as shown in FIG.
A metal layer 82 is formed on a metal plate 81. This step can be performed by cladding, thermal spraying, plating such as PVD, CVD, or electroplating. When forming a Ti layer, cladding, thermal spraying, PVD, and CVD are preferable, and
When forming a layer, cladding, thermal spraying, PVD, CVD,
Electroplating is preferred. The formation of the Cr layer is advantageous because electroplating that can be performed at low cost can be used. Then
After smoothing as necessary, as shown in FIG. 8C, the metal plate 81 is formed so as to have a required shape such as a groove 85.
Is processed by a press or the like. After that, the strain is removed by heat treatment or the like as necessary, and further, the metal layer 8 is formed as necessary.
The oxide film formed on the surface of No. 2 is removed by plasma etching or the like. Next, a nitriding process is performed to nitride the metal layer to form a protective layer 92, as shown in FIG. The nitriding can be performed by the same method as described above. Thus, by nitriding the metal layer, a nitride film having good corrosion resistance can be obtained at low cost.

According to the present invention, a relatively thin separator having a thickness of 0.2 to 2.0 mm, preferably 0.5 to 1.0 mm can be provided. Further, according to the present invention, 10
0-500cm ² area, preferably 200-300c
A separator having an area of m ² can be provided with high processing accuracy. Such a separator is suitable for a fuel cell having about 400 cells, particularly a fuel cell for a vehicle such as an automobile.

[0023]

EXAMPLES Example 1 A SUS430 plate (Fe-
(18 wt% Cr alloy) was cut into a size of 150 mm × 150 mm, and grooving was performed by press working. Then, a 50 μm thick Cr
A layer was formed. For chromium plating, an aqueous plating solution containing 150 g / l chromic anhydride, 2.0 g / l sulfuric acid, and 1.5 g / l chromium sulfate and having a Baume specific gravity of 13.5 was used. The grooved SUS plate was placed in a plating bath, and electroplating was performed at a temperature of 50 ° C. and a current density of 10 A / dm ² . Then, SUS430 plated with Cr
The plate was nitrided. In the nitriding treatment, a DC voltage of 300 V was applied between the electrodes under a nitrogen mixed gas atmosphere of 1 Torr, with the furnace body as the anode and the SUS plate as the cathode. During this process, SU
The S plate was heated to 600 ° C., and a composition of N ₂ : H ₃ : CO ₂ = 1: 1: 0.07 was used as a nitrogen mixed gas. By this treatment, the Cr layer was nitrided, and a separator having a protective film was obtained.

Next, the SUS plate was cut into a size of 10 mm square, embedded in a resin, polished, and the distribution of N concentration in the cross section was measured by an EPMA (electron probe microanalysis) apparatus. As a result, FIG.
As shown in the figure, the N concentration was higher toward the surface, and decreased toward the inside, so that N was not detected at a depth of about 20 μm. As nitrides, a large amount of CrN is detected in a portion near the surface, and in the inside, Cr ₂ N
Was detected many times. Cr remained inside. C
The structure of the film containing r-nitride was dense. Also,
The portion of SUS430 near Cr and the portion of Cr were recrystallized, and their average grain size was about 12 μm.

Example 2 A SUS310S plate having a thickness of 1.0 mm, which was rolled,
A Ti film having a thickness of 100 μm was formed on the surface by thermal spraying. Then, by pressing, while smoothing the surface,
Grooving was performed. Then, N ₂ : H ₃ : CO ₂ = 1:
In an atmosphere having a composition of 1: 0.07, the Ti-coated SUS plate was heated at 973K for 5 hours to form a nitride film on the surface, thereby obtaining a separator. EPM as in Example 1
As a result of measuring the distribution of N concentration in the cross-sectional direction by A, FIG.
As shown in Fig. 0, it was found that the N concentration continuously decreased from the surface, and N almost disappeared at a depth of about 50 µm. The portion near the surface was dominated by TiN, and Ti ₂ N was detected inside. As shown in FIG. 10, a protective film having a higher N concentration toward the surface was obtained. SUS31
The structure of 0S was a recrystallized structure having almost no processed structure, and the average crystal grain size was 20 μm.

Comparative Example 1 A SUS304 plate having a thickness of 2 mm that was rolled was rolled to a thickness of 150 mm.
After cutting into a size of 150 mm, grooving was performed by press working to obtain a separator. In the obtained separator, SUS had a rolled structure.

Comparative Example 2 A rolled SUS304 plate having a thickness of 0.5 mm and 150
After cutting into a size of mm × 150 mm, grooving was performed by press working. Next, the SUS plate was set in a vacuum chamber, and after evacuation, ion plating was performed on the surface under vacuum for 5 hours to deposit a 3 μm-thick TiN film to obtain a separator. As a result of measuring the distribution of N concentration from the surface by EPMA, it was found that the N concentration was uniform over the entire thickness of 3 μm. SUS304 is
It had a rolled structure.

Comparative Example 3 A rolled SUS310S plate having a thickness of 0.5 mm and 15
After cutting into a size of 0 mm x 150 mm, grooving was performed by press working. Next, the SUS plate was placed in a vacuum chamber, and after evacuation to 5 to 10 Torr, N ₂ gas was introduced into the chamber and adjusted to ₂ to 10 Torr.
Reactive sputtering was performed for 10 hours using a Ti target, and a 3 μm thick TiN film was deposited on the SUS plate surface to obtain a separator. N from surface by EPMA
As a result of measuring the concentration distribution, it was found that the N concentration was uniform over the entire thickness of 3 μm. SUS310S
Had a rolled structure.

Examples 1 and 2 and Comparative Examples 1 to 3
Using these separators, a polymer electrolyte fuel cell was produced. Polymer electrolyte membranes include Du Pon
t) A Nafion membrane manufactured by the company was used, and a mixture of carbon black and polytetrafluoroethylene (PTFE) was used for the electrode. A continuous output test was performed on the obtained cell sample. In the sample of Comparative Example 1, during output,
When the internal resistance gradually increases, the output decreases by about 20% in 5 hours, and at a current density of 0.5 A / cm ² , 0.6 V
Decreased to 0.5V. In the sample of Comparative Example 2, although the degree of the output decrease was low, the initial voltage of 0.6 V was reduced to 0.5 V with the output for continuous 100 hours. In the sample of Comparative Example 3, the initial voltage of 0.6 V was reduced to 0.5 V in 75 consecutive hours. In the samples of Comparative Examples 2 and 3, as a result of observing the separator after the test, TiN
Rust was generated between the film and the SUS plate. On the other hand, Example 1
And 2 samples, even for 500 hours of continuous operation,
The initial voltage of 0.6V did not change. As a result of observing the separator of each example after the test, no rust was generated,
The protective layer was sufficiently adhered to the SUS plate.

[0030]

As described above, according to the present invention,
A separator having good corrosion resistance and little change in electric resistance during use can be provided. The separator according to the present invention can be formed by plastic working or the like, and can be manufactured with high working accuracy. The separator according to the present invention can have high fatigue strength, and can have good durability that can be used over a long period of time with little deterioration. Further, the separator according to the present invention can be provided at low cost. The separator according to the present invention is particularly suitable for a fuel cell for a vehicle such as an automobile.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing an example of the structure of a polymer electrolyte fuel cell.

FIG. 2 is a schematic sectional view showing an example of a separator according to the present invention.

FIGS. 3 (a) and (b) are diagrams showing an example of the relationship between the depth from the surface and the N content for a protective layer of a separator according to the present invention.

FIG. 4 is a schematic sectional view showing another example of the separator according to the present invention.

FIG. 5 is a schematic sectional view showing a further example of a separator according to the present invention.

FIG. 6 is a schematic sectional view showing a further example of a separator according to the present invention.

FIGS. 7A to 7C are schematic sectional views showing an example of a method for producing a separator according to the present invention.

FIGS. 8A to 8D are schematic sectional views showing another example of the method for producing a separator according to the present invention.

FIG. 9 is a view showing an N concentration distribution in a protective layer of Example 1.

FIG. 10 is a diagram showing an N concentration distribution in a protective layer of Example 2.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Polymer electrolyte membrane 12 Negative electrode 13 Positive electrode 14, 15, 20, 40, 50, 60 Separator 21, 41, 51, 61a, 61b Metal material layer 22, 42, 52, 62, 72, 92 Protection layer

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takeshi Miyazaki 1-3-1 Shimaya, Konohana-ku, Osaka Sumitomo Electric Industries, Ltd. Osaka Works F-term (reference) 5H026 AA06 BB01 BB02 BB04 BB06 BB10 CC05 CX04 EE02 EE06 EE11

Claims (13)

[Claims] 1. A separator having a passage for supplying an oxidant or a fuel to a positive electrode or a negative electrode laminated on a polymer electrolyte membrane, comprising: a metal material layer; and a protective layer covering the metal material layer. Wherein the protective layer contains a metal nitride, and the N content in the protective layer decreases from the surface of the protective layer to the inside thereof, for a polymer electrolyte fuel cell. Separator. 2. The method according to claim 1, wherein the metal nitride is Ti, Ti alloy, C
r, Cr alloy, Zr, Zr alloy, Hf, Hf alloy, V,
The separator according to claim 1, wherein the separator is at least one selected from the group consisting of V alloy, Nb, Nb alloy, Ta, and a nitride of Ta alloy. 3. The method according to claim 1, wherein the metal nitride is Ti nitride, and the protective layer is TiN as Ti nitride.
The separator according to claim 1, comprising at least one of Ti and N ₂ . 4. The metal nitride is a Cr nitride, and the protective layer is a Cr nitride as the Cr nitride.
N, Cr ₂ N, characterized in that it comprises at least one selected from the group consisting of CrN ₂ and Cr (N _{3) 3,} separator according to claim 1. 5. The separator according to claim 1, wherein the metal material is made of titanium, and the protective layer is formed by nitriding the titanium. 6. The metal material includes a first metal, the metal nitride is a second metal nitride different from the first metal, and the metal nitride is a first metal. 5. The method according to claim 1, wherein said second metal is formed by nitriding said second metal deposited on said metal.
The separator according to any one of the above. 7. The method according to claim 1, wherein the first metal is stainless steel, and the second metal is at least one selected from the group consisting of Ti, Ti alloy, Cr and Cr alloy. The separator according to claim 6, wherein 8. The method according to claim 1, wherein the first metal is aluminum, and the second metal is at least one selected from the group consisting of Ti, Ti alloy, Cr, and Cr alloy. The separator according to claim 6. 9. The metal material is Fe, an Fe alloy, N
i, Ni alloy, Cr, Cr alloy, Cu, Cu alloy, A
and at least one selected from the group consisting of 1, Al alloy, Ti and Ti alloy.
The separator according to any one of claims 4 to 4. 10. A method for producing a separator having a passage for supplying an oxidizing agent or a fuel to a positive electrode or a negative electrode laminated on a polymer electrolyte membrane, wherein a metal plate is processed into a shape having at least the passage. And a step of nitriding the surface of the processed metal plate. A method for producing a separator for a polymer electrolyte fuel cell, comprising: 11. The method according to claim 10, wherein the metal plate is made of Ti or a Ti alloy. 12. A method for producing a separator having a passage for supplying an oxidizing agent or a fuel to a positive electrode or a negative electrode laminated on a polymer electrolyte membrane, wherein Ti, Ti alloy, Cr, Cr alloy is formed on a metal plate. , Zr, Z
depositing at least one metal selected from the group consisting of r alloy, Hf, Hf alloy, V, V alloy, Nb, Nb alloy, Ta and Ta alloy; and nitriding the deposited metal. A method for producing a separator for a polymer electrolyte fuel cell, comprising: 13. The manufacturing method according to claim 12, further comprising, after the depositing step, a step of processing the metal plate into a shape having at least the passage.