JP5912901B2 - Fuel cell - Google Patents

Description

  The present invention relates to a fuel cell in which an electrolyte / electrode structure in which an anode side electrode and a cathode side electrode are provided on both sides of an electrolyte and a separator are laminated.

  For example, a polymer electrolyte fuel cell employs an electrolyte membrane (electrolyte) made of a polymer ion exchange membrane. A fuel cell is configured by sandwiching an electrolyte membrane / electrode structure (MEA) in which an anode side electrode and a cathode side electrode are disposed on both sides of the electrolyte membrane with a separator.

  In the fuel cell described above, it is necessary to accurately grasp the power generation status in order to reliably perform desired power generation. For example, the electrolyte membrane must be moistened to a desired wet state in order to maintain the power generation performance. When the electrolyte membrane is in a dry state, the power generation performance is degraded.

  On the other hand, when the amount of water generated by power generation is large and the water becomes excessive, flooding is likely to occur. For this reason, the channel | path etc. which distribute | circulate reaction gas will be blocked, and electric power generation performance will fall. In addition, performance degradation may occur due to a shortage of fuel gas.

  Therefore, for example, a fuel cell driving device disclosed in Patent Document 1 is known. In this fuel cell, as shown in FIG. 13, an anode 2a and a cathode 3a are joined so as to sandwich a solid polymer electrolyte membrane 1a, and a fuel gas channel 5a and an oxidizing gas channel 6a are respectively formed on the outside thereof. Preliminarily formed separators 4a are arranged so as to sandwich them from both ends.

  On the anode 2a side of the fuel cell, one end of the platinum wire 7a is held so as to contact the solid polymer electrolyte membrane 1a at a position where it does not contact the anode 2a. This contact portion is the anode of the reference electrode. Further, the platinum wire 7a is arranged so as to touch the solid polymer electrolyte membrane 1a and at the same time, the hydrogen gas as the fuel gas. That is, the platinum wire 7a functions as an anode of a standard hydrogen electrode that is one of the reference electrodes.

Further, the other end of the standard hydrogen electrode is connected to a separator 4a on the anode 2a side and a separator 4a on the cathode 3a side of the fuel cell, respectively, and each separator 4a serves as cathodes 8a and 9a. Further, in order to measure the voltage V ₃ between the anode 2a side and the cathode 3a of the fuel cell, the separator 4a of each electrode of the fuel cell are connected by a conductive wire, respectively, via a voltmeter.

With the above-described configuration, when the anode 2a side of the fuel cell is operating in a normal (ideal behavior in terms of electrochemical) state, the potential of the anode 2a matches the potential of the platinum wire 7a, and the anode 2a and the platinum wire voltages _{V 1} between 7a is zero, the voltage _{V 2} is equal to the voltage _{V 3.}

  Further, as shown in FIG. 14, the fuel cell disclosed in Patent Document 2 includes an electrolyte membrane 1b, an anode side catalyst layer / diffusion layer 2b divided into four parts, and a cathode side catalyst layer / diffusion divided into four parts. A plurality of insulating members 8b disposed between the layer 3b, the four-divided anode-side separator 4b, the four-divided cathode-side separator 5b, and between the plurality of anode-side separators 4b and between the plurality of cathode-side separators 5b. , 9b.

  An anode gas flow path 6b is formed between each anode-side separator 4b and each anode-side catalyst layer / diffusion layer 2b, and between each cathode-side separator 5b and each cathode-side catalyst layer / diffusion layer 3b. Is formed with a cathode gas flow path 7b. An insulating member 8b is interposed between the anode separators 4b, and an insulating member 9b is interposed between the cathode separators 5b.

  For this reason, the fuel cell can operate as four independent divided cells, and the impedance distribution of the fuel cell can be measured by measuring the impedance of each divided cell.

Japanese Patent Laid-Open No. 7-282832 JP 2008-27808 A

  However, although Patent Document 1 described above can measure the impedance of the entire fuel cell, it is difficult to accurately measure the in-electrode environment distribution (impedance distribution) inside the fuel cell. For this reason, there is a problem that the fuel cell cannot be efficiently controlled.

  In the fuel cell of Patent Document 2, the anode side catalyst layer / diffusion layer 2b divided into four parts and the cathode side catalyst layer / diffusion layer 3b divided into four parts are provided. Therefore, when this fuel cell is used for normal power generation, the power generation area of the entire fuel cell is reduced. As a result, the power generation efficiency of the entire fuel cell is lowered, and there is a problem that the fuel cell cannot be easily downsized.

  The present invention solves this type of problem, and provides a fuel cell capable of easily and accurately measuring the impedance distribution on the electrode reaction surface of the fuel cell while suppressing a decrease in power generation efficiency. With the goal.

The invention, together with the anode-side electrodes are continuously formed integrally on one surface of the electrolyte, the cathode is the electrolyte of the other side electrolyte electrode continuously provided integrally on body and the separator The present invention relates to a fuel cell in which and are stacked.

  In this fuel cell, the separator has a frame member in which a fuel gas communication hole, an oxidant gas communication hole, and a cooling medium communication hole are formed in the outer peripheral portion so as to penetrate in the stacking direction of the separator. And a plurality of conductive members that are provided in the region of the electrode reaction surface while being maintained in an insulating state.

The plurality of conductive members include gas flow paths through which fuel gas or oxidant gas is passed along the electrode reaction surface, and the plurality of conductive members of the separator stacked on the anode side electrode; The plurality of conductive members of the separator laminated on the cathode side electrode are arranged opposite to each other at symmetrical positions across the electrolyte / electrode structure, and impedance between the conductive members facing each other is set. Each is connected to a measuring means for measuring .

  In this fuel cell, it is preferable that the conductive members are arranged in a lattice shape with a non-conductive member interposed in the frame member.

  According to the present invention, since the separator region facing the electrode reaction surface of the electrolyte / electrode structure is divided into a plurality of regions and a plurality of conductive members are provided, the impedance distribution of each region in the electrode reaction surface Can be measured easily and accurately. For this reason, it becomes possible to measure the environmental distribution in the electrode surface with high accuracy, and the desired power generation state can be reliably maintained.

  Furthermore, the anode side electrode and the cathode side electrode are not divided and are continuously provided on both sides of the electrolyte. Moreover, a gas flow path is formed in the conductive member. Therefore, it is possible to suppress a decrease in power generation efficiency and reliably perform good power generation, and can be suitably used as a fuel cell.

It is a principal part disassembled perspective view of the fuel cell stack in which the fuel cell which concerns on the 1st Embodiment of this invention is integrated. It is a principal part disassembled perspective view of the said fuel cell. It is principal part cross-sectional explanatory drawing of the said fuel cell. It is front explanatory drawing of the 2nd separator which comprises the said fuel cell. It is a schematic explanatory drawing of an in-plane environment measuring device. It is a principal part disassembled perspective view of the fuel cell which concerns on the 2nd Embodiment of this invention. It is a principal part disassembled perspective view of the fuel cell which concerns on the 3rd Embodiment of this invention. It is front explanatory drawing of the 1st separator which comprises the said fuel cell. It is front explanatory drawing of the 2nd separator which comprises the said fuel cell. It is a principal part disassembled perspective view of the fuel cell which concerns on the 4th Embodiment of this invention. It is front explanatory drawing of the 1st separator which comprises the said fuel cell. It is front explanatory drawing of the 2nd separator which comprises the said fuel cell. It is a partial cross section explanatory drawing of the drive device currently disclosed by patent document 1. FIG. 4 is a cross-sectional explanatory view of a fuel cell disclosed in Patent Document 2. FIG.

  As shown in FIG. 1, the fuel cell 10 according to the first embodiment of the present invention is incorporated in a fuel cell stack 12. The fuel cell stack 12 is configured by stacking at least one fuel cell 10 and a plurality of fuel cells 10a and, for example, as an in-vehicle fuel cell stack. The fuel cell 10 and the fuel cell 10a have the same position and size of communication holes, which will be described later, and the shape of the flow channel, and the same electrode position and size.

  As shown in FIGS. 1 and 2, the fuel cell 10 includes an electrolyte membrane / electrode structure (electrolyte / electrode structure) (MEA) 14, a first separator 16 that sandwiches the electrolyte membrane / electrode structure 14, and A second separator 18. One end edge (upper end edge) of the fuel cell 10 in the arrow C direction (vertical direction in FIG. 1) communicates with each other in the direction of arrow A, which is the stacking direction, and an oxidant gas, for example, an oxygen-containing gas. An oxidant gas supply communication hole 20a for supplying and a fuel gas supply communication hole 22a for supplying a fuel gas, for example, a hydrogen-containing gas, are arranged in an arrow B direction (horizontal direction).

  The other end edge (lower end edge) of the fuel cell 10 in the direction of arrow C communicates with each other in the direction of arrow A, and the fuel gas discharge communication hole 22b for discharging the fuel gas and the oxidant gas are discharged. The oxidant gas discharge communication holes 20b are arranged in the direction of the arrow B.

  A cooling medium supply communication hole 24a for supplying a cooling medium is provided at one edge of the fuel cell 10 in the direction of arrow B, and a cooling medium is provided at the other edge of the fuel cell 10 in the direction of arrow B. Is provided with a cooling medium discharge communication hole 24b.

  The electrolyte membrane / electrode structure 14 includes, for example, a solid polymer electrolyte membrane 26 in which a perfluorosulfonic acid thin film is impregnated with water, and a cathode side electrode 28 and an anode side electrode 30 that sandwich the solid polymer electrolyte membrane 26. With.

  As shown in FIG. 3, the cathode side electrode 28 and the anode side electrode 30 are disposed on the electrode catalyst layers 28a and 30a bonded to both surfaces of the solid polymer electrolyte membrane 26 and the electrode catalyst layers 28a and 30a. Gas diffusion layers 28b and 30b made of carbon paper or the like. The electrode catalyst layers 28 a and 30 a are formed by uniformly applying porous carbon particles having a platinum alloy supported on the both surfaces of the solid polymer electrolyte membrane 26.

  As shown in FIG. 2, the first separator 16 penetrates the outer peripheral portion in the stacking direction (arrow A direction), and the oxidizing gas supply communication hole 20a, the fuel gas supply communication hole 22a, the cooling medium supply communication hole 24a, the oxidation An insulating resin frame member 32 is provided in which the agent gas discharge communication hole 20b, the fuel gas discharge communication hole 22b, and the cooling medium discharge communication hole 24b are formed.

  The insulating resin frame member 32 is formed of a non-conductive resin such as PP (polypropylene) or ABS resin (a copolymer resin of acrylonitrile, butadiene and styrene).

  In the insulating resin frame member 32, a plurality of conductive segments (conductive members) 34 are provided in the region of the electrode reaction surface while being kept insulated from each other. The conductive segment 34 has a rectangular parallelepiped shape or a cubic shape, and is formed of a conductive resin containing carbon or the like. The insulating resin frame member 32 may be a thermoreversible resin or a thermosetting resin. The melting point of the resin used can be adjusted by the molecular weight and molecular structure.

  Each conductive segment 34 is arranged in a lattice shape with a thermally reversible non-conductive resin (non-conductive member) 36 such as PP or ABS resin interposed in the central region of the insulating resin frame member 32. The non-conductive resin 36 and the insulating resin frame member 32 are preferably the same type of resin. This is because the interface is easy to join. The non-conductive resin 36 and the insulating resin frame member 32 may be integrally formed with the same resin.

  The first separator 16 is provided with an oxidant gas flow path 38 on a surface 16 a facing the electrolyte membrane / electrode structure 14. The oxidant gas channel 38 has a plurality of linear (or non-linear, such as serpentine) channel grooves formed in the conductive segment 34 and the nonconductive resin 36 and extending in the direction of arrow C. The oxidant gas supply communication hole 20a and the oxidant gas discharge communication hole 20b communicate with each other.

  The flow channel is provided in the surface of each conductive segment 34 and is formed so as to avoid the portion of the nonconductive resin 36 extending in the direction of arrow C. The channel groove may be provided in a portion of the nonconductive resin 36 extending in the arrow C direction. Each conductive segment 34 has the same MEA contact area (contact area with the electrolyte membrane / electrode structure 14).

  As shown in FIG. 4, the second separator 18 penetrates the outer peripheral portion in the stacking direction (arrow A direction), and the oxidant gas supply communication hole 20a, the fuel gas supply communication hole 22a, the cooling medium supply communication hole 24a, the oxidation An insulating resin frame member 40 in which the agent gas discharge communication hole 20b, the fuel gas discharge communication hole 22b, and the cooling medium discharge communication hole 24b are formed is provided.

  The insulating resin frame member 40 is formed of a non-conductive resin such as PP or ABS resin, and a plurality of insulating resin frame members 40 are maintained in an insulated state in the region of the electrode reaction surface in the insulating resin frame member 40. A conductive segment (conductive member) 42 is provided.

  Each conductive segment 42 is arranged in a lattice shape with a non-conductive resin (non-conductive member) 44 such as PP or ABS resin interposed in the central region of the insulating resin frame member 40. The non-conductive resin 44 and the insulating resin frame member 40 may be integrally formed with the same resin. Each conductive segment 42 has the same MEA contact area (contact area with the electrolyte membrane / electrode structure 14).

  The second separator 18 is provided with a fuel gas flow path 46 on a surface 18 a facing the electrolyte membrane / electrode structure 14. The fuel gas channel 46 has a plurality of channel grooves formed in the conductive segment 42 and the non-conductive resin 44 and extending in the direction of the arrow C, and communicates with the fuel gas supply communication hole 22a and the fuel gas discharge communication. It communicates with the hole 22b. The flow channel is provided in the surface of each conductive segment 42 and is formed so as to avoid a portion of the nonconductive resin 44 extending in the arrow C direction. The channel groove may be provided in a portion of the nonconductive resin 44 extending in the arrow C direction.

  As shown in FIG. 3, each conductive segment 34 is exposed on both surfaces of the first separator 16, and each conductive segment 42 is exposed on both surfaces of the second separator 18. The conductive segment 34 and the conductive segment 42 are disposed opposite to (symmetrically) the electrolyte membrane / electrode structure 14. This is because the detection accuracy decreases if they deviate from each other.

  The first separator 16 and the second separator 18 are provided with a first seal member 48 and a second seal member 49 integrally or individually to seal the fuel gas, the oxidant gas, and the cooling medium, respectively. The first seal member 48 and the second seal member 49 are, for example, EPDM, NBR, fluororubber, silicone rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroplane, or acrylic rubber, or a cushion material. Alternatively, an elastic seal member such as a packing material is used.

  As shown in FIG. 1, the fuel cell 10 a includes an electrolyte membrane / electrode structure 14, and a first separator 50 and a second separator 52 that sandwich the electrolyte membrane / electrode structure 14. In the fuel cell 10a, the same components as those of the fuel cell 10 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As the first separator 50 and the second separator 52, a metal separator or a carbon separator is used. On the surface of the first separator 50 on the side opposite to the electrolyte membrane / electrode structure 14, a cooling medium flow path 54 is provided for flowing the cooling medium in the direction of arrow B along the region of the electrode reaction surface. Similarly, a cooling medium flow path 54 is formed on the surface of the second separator 52 opposite to the electrolyte membrane / electrode structure 14. Note that the coolant flow path 54 may also be formed on the surface 16 b of the first separator 16 and the surface 18 b of the second separator 18.

  As shown in FIG. 5, the fuel cell stack 12 is connected to the in-plane environment measuring device 60. The in-plane environment measuring device 60 includes wirings 62a, 62b, 62c, 62d and 62e whose ends are connected to the conductive segments 34 of the first separator 16, and the conductive segments 42 whose ends are the second separator 18. Wirings 63a, 63b, 63c, 63d and 63e electrically connected to each other. The wirings 62a to 62e and the wirings 63a to 63e are provided with AC voltage measuring devices 64a, 64b, 64c, 64d and 64e for detecting an AC voltage, respectively. Note that the number of wirings can be variously changed according to the number of divisions of the conductive segments 34 and 42.

  Both ends of the wiring 66 are electrically connected to both ends of the fuel cell stack 12 in the stacking direction. The wiring 66 is provided with an external load 68 and an AC current measuring device 70 for detecting AC current. The external load 68 has a function of outputting a direct current from the fuel cell stack 12 and superimposing an alternating current on the direct current. For example, an electronic load device is used as the external load 68, but a current amplifier or the like can be used instead.

  The operation of the fuel cell stack 12 configured as described above will be described below.

  As shown in FIG. 1, an oxidant gas such as an oxygen-containing gas is supplied to the oxidant gas supply communication hole 20a, and a fuel gas such as a hydrogen-containing gas is supplied to the fuel gas supply communication hole 22a. Further, a cooling medium such as pure water or ethylene glycol is supplied to the cooling medium supply communication hole 24a.

  The oxidant gas is introduced into each oxidant gas flow path 38 provided in the first separator 16, 50 and moves along the cathode side electrode 28 constituting the electrolyte membrane / electrode structure 14. On the other hand, the fuel gas supplied to the fuel gas supply communication hole 22 a is introduced into the fuel gas flow paths 46 of the second separators 18 and 52, and along the anode side electrode 30 constituting the electrolyte membrane / electrode structure 14. Moving.

  Therefore, in each electrolyte membrane / electrode structure 14, the oxidant gas supplied to the cathode side electrode 28 and the fuel gas supplied to the anode side electrode 30 are electrochemically reacted in the electrode catalyst layers 28 a and 30 a. It is consumed and power is generated.

  Next, the oxidant gas consumed by being supplied to the cathode side electrode 28 is discharged to the oxidant gas discharge communication hole 20b. Similarly, the fuel gas supplied to and consumed by the anode side electrode 30 is discharged to the fuel gas discharge communication hole 22b.

  Further, the cooling medium supplied to the cooling medium supply communication hole 24 a is introduced into each cooling medium flow path 54 of the first separator 50 and the second separator 52. The cooling medium cools the electrolyte membrane / electrode structure 14 and then is discharged into the cooling medium discharge communication hole 24b.

  During the above power generation, as shown in FIG. 5, in the in-plane environment measuring device 60, a DC current is output from the fuel cell stack 12 by the external load 68, and an AC current is superimposed on this DC current.

  For this reason, the AC voltage measuring devices 64 a to 64 e measure the AC voltage with respect to the AC current, while the AC current measuring device 70 measures the AC current. Accordingly, the AC impedance between the conductive segments 34 and 42 is calculated from the measured AC voltage and AC current. Thereby, the impedance distribution of the entire fuel cell 10 is detected, and the power generation state in the electrode surface of the fuel cell 10 can be detected.

  In this case, in the first embodiment, the separator region facing the electrode reaction surface of the electrolyte membrane / electrode structure 14 constituting the fuel cell 10 is divided into a plurality of regions, and a plurality of conductive segments 34 and 42 are formed. Is provided. For this reason, the alternating current impedance of each area | region in an electrode reaction surface can be measured, and it becomes possible to detect an impedance distribution easily and correctly. Therefore, the environmental distribution in the electrode surface of the fuel cell 10 can be measured with high accuracy, and the desired power generation state can be reliably maintained.

  Further, in the fuel cell 10, the cathode side electrode 28 and the anode side electrode 30 are integrated without being divided, and are continuously provided on both surfaces of the solid polymer electrolyte membrane 26. In addition, an oxidant gas flow path 38 is formed on the surface of the plurality of conductive segments 34, while a fuel gas flow path 46 is formed on the surface of the plurality of conductive segments 42.

  As a result, the fuel cell 10 can suppress a decrease in power generation efficiency due to a decrease in the power generation area and can reliably perform good power generation. As the fuel cell 10 constituting the fuel cell stack 12, another fuel can be used. There exists an advantage that it can be used conveniently like the battery 10a.

  In the first embodiment, the AC impedance method is employed to measure the internal resistance of the fuel cell 10, but the present invention is not limited to this. For example, a current interruption method may be applied in which a constant current is passed through the fuel cell 10 and the internal resistance is measured from a voltage change when the current is momentarily interrupted. It is also possible to apply a step method in which a constant current is passed through the fuel cell 10 and the internal resistance is measured from the voltage change when the current is changed stepwise.

  As shown in FIG. 6, the fuel cell 80 according to the second embodiment of the present invention is incorporated in a fuel cell stack (not shown) together with a plurality of fuel cells 10a (see FIG. 1).

  The same components as those of the fuel cell 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Similarly, in the third and fourth embodiments described below, detailed description thereof is omitted.

  The fuel cell 80 includes an electrolyte membrane / electrode structure 14, and a first separator 82 and a second separator 84 that sandwich the electrolyte membrane / electrode structure 14. The first separator 82 has an oxidant gas supply communication hole 20a, a fuel gas supply communication hole 22a, a cooling medium supply communication hole 24a, an oxidant gas discharge communication hole 20b, a fuel gas discharge communication hole 22b, and a cooling medium discharge communication at the outer periphery. The metal frame member 86 in which the hole 24b is formed is provided. The metal frame member 86 is made of, for example, iron or aluminum.

  In the metal frame member 86, a thermoreversible non-conductive resin (non-conductive member) 88 such as PP or ABS resin formed in a lattice shape is integrated, and each non-conductive resin 88 is interposed through the non-conductive resin 88. Conductive segments 34 are arranged in a grid.

  The second separator 84 has an oxidant gas supply communication hole 20a, a fuel gas supply communication hole 22a, a cooling medium supply communication hole 24a, an oxidant gas discharge communication hole 20b, a fuel gas discharge communication hole 22b, and a cooling medium discharge communication at the outer periphery. The metal frame member 90 in which the hole 24b is formed is provided.

  In the metal frame member 90, a thermoreversible non-conductive resin (non-conductive member) 92 such as PP or ABS resin formed in a lattice shape is integrated, and the non-conductive resin 92 is used for each. Conductive segments 42 are arranged in a grid pattern.

  In the second embodiment configured as described above, the same effect as in the first embodiment can be obtained.

  As shown in FIG. 7, the fuel cell 100 according to the third embodiment of the present invention is incorporated in a fuel cell stack (not shown) together with a plurality of fuel cells 10a (see FIG. 1).

  The fuel cell 100 includes an electrolyte membrane / electrode structure 14, and a first separator 102 and a second separator 104 that sandwich the electrolyte membrane / electrode structure 14. In the first separator 102, as shown in FIGS. 7 and 8, the conductive segments 34 are arranged in a lattice shape with a non-conductive resin 36 interposed in the central region of the insulating resin frame member 32.

  The first separator 102 is provided with an oxidant gas flow path 38 a on a surface 102 a facing the electrolyte membrane / electrode structure 14. The oxidant gas flow path 38a has a plurality of wave-shaped flow path grooves formed in the conductive segments 34 and the non-conductive resin 36 and extending in the direction of arrow C. The wavy channel groove has a wavelength (period) λ1, and the wavelength λ1 × 2 is set to the same dimension as the arrangement interval (pitch) P1 of the conductive segments 34 in the arrow C direction (λ1 × 2 = P1). . Each conductive segment 34 has the same contact shape and contact area with the electrolyte membrane / electrode structure 14. Note that the relationship of wavelength λ1 = arrangement interval P1 may be set, and it is sufficient if wavelength λ1 × integer = arrangement interval P1.

  As shown in FIG. 9, in the second separator 104, the conductive segments 42 are arranged in a lattice shape with a non-conductive resin 44 interposed in the central region of the insulating resin frame member 40. The second separator 104 is provided with a fuel gas channel 46 a on a surface 104 a facing the electrolyte membrane / electrode structure 14. The fuel gas channel 46 a has a plurality of wave-shaped channel grooves formed in the conductive segments 42 and the non-conductive resin 44 and extending in the direction of arrow C.

  The wavy channel groove has a wavelength (period) λ2, and the wavelength λ2 × 2 is set to the same dimension as the arrangement interval (pitch) P2 of the conductive segments 42 in the arrow C direction (λ × 2 = P2). . Each conductive segment 42 has the same contact shape and contact area with the electrolyte membrane / electrode structure 14. Further, the relationship of wavelength λ2 = arrangement interval P2 may be set. The wavelength λ1 is the same as the wavelength λ2, and the arrangement interval P1 is the same as the arrangement interval P2.

  In the third embodiment configured as described above, each of the conductive segments 34 and each of the conductive segments 42 has an undulating oxidant gas flow path 38a and a undulated fuel gas flow path 46a. The contact shape and contact area with the membrane / electrode structure 14 are set to be the same. For this reason, the environment distribution in the electrode surface of the fuel cell 100 can be measured with high accuracy, and the desired power generation state can be reliably maintained. can get.

  As shown in FIG. 10, the fuel cell 120 according to the fourth embodiment of the present invention is incorporated in a fuel cell stack (not shown) together with a plurality of fuel cells 10a (see FIG. 1).

  The fuel cell 120 includes an electrolyte membrane / electrode structure 14, and a first separator 122 and a second separator 124 that sandwich the electrolyte membrane / electrode structure 14. In the first separator 122, as shown in FIGS. 10 and 11, the conductive segments 34 a are arranged in a lattice shape with the nonconductive resin 36 interposed in the central region of the insulating resin frame member 32. The conductive segment 34a has a square shape when viewed from the front.

  The first separator 122 is provided with an oxidant gas flow path 38 b on a surface 122 a facing the electrolyte membrane / electrode structure 14. The oxidant gas flow path 38b has a plurality of wave-shaped flow path grooves formed in the conductive segment 34a and the non-conductive resin 36 and extending in the direction of arrow C. The wavy channel groove has a wavelength (period) λ3, and the wavelength λ3 is set to a size different from the arrangement interval (pitch) P3 of the conductive segments 34a in the arrow C direction. Each conductive segment 34a has a different contact shape with the electrolyte membrane / electrode structure 14 and has the same contact area.

  As shown in FIG. 12, in the second separator 124, the conductive segments 42 a are arranged in a lattice shape with a non-conductive resin 44 interposed in the central region of the insulating resin frame member 40. The conductive segment 42a has a square shape when viewed from the front.

  The second separator 124 is provided with a fuel gas channel 46 b on a surface 124 a facing the electrolyte membrane / electrode structure 14. The fuel gas channel 46b has a plurality of wave-shaped channel grooves formed in the conductive segment 42a and the non-conductive resin 44 and extending in the direction of arrow C. The wavy channel groove has a wavelength (period) λ4, and the wavelength λ4 is set to a dimension different from the arrangement interval (pitch) P4 in the direction of arrow C of the conductive segments 42a. Each conductive segment 42a has a different contact shape with the electrolyte membrane / electrode structure 14 and has the same contact area.

  In the fourth embodiment configured as described above, each of the conductive segments 34a and each of the conductive segments 42a includes an undulating oxidant gas channel 38b and a undulated fuel gas channel 46b. The contact area with the membrane / electrode structure 14 is set to be the same. Accordingly, the environmental distribution in the electrode surface of the fuel cell 120 can be accurately measured, and the desired power generation state can be reliably maintained, and the same as in the first and third embodiments described above. An effect is obtained.

10, 10a, 80, 100, 120 ... Fuel cell 12 ... Fuel cell stack 14 ... Electrolyte membrane / electrode structure 16, 18, 50, 52, 82, 84, 102, 104, 122, 124 ... Separator 20a ... Oxidant Gas supply communication hole 20b ... Oxidant gas discharge communication hole 22a ... Fuel gas supply communication hole 22b ... Fuel gas discharge communication hole 24a ... Cooling medium supply communication hole 24b ... Cooling medium discharge communication hole 26 ... Solid polymer electrolyte membrane 28 ... Cathode Side electrode 28a, 30a ... Electrode catalyst layer 28b, 30b ... Gas diffusion layer 30 ... Anode side electrode 32, 40 ... Insulating resin frame members 34, 34a, 42, 42a ... Conductive segments 36, 44, 88, 92 ... Non Conductive resins 38, 38a, 38b ... Oxidant gas channels 46, 46a, 46b ... Fuel gas channels 48, 49 ... Seal members 54 ... Cooling medium Road 60 ... plane environment measuring device 62a to 62e, 63 a to 63 e, 66 ... wiring 64A～64e ... AC voltmeter 68 ... external load 70 ... AC current measuring device

Claims (2)

With the anode electrodes are continuously formed integrally on one surface of the electrolyte, and the electrolyte electrode assembly and separators disposed cathode is continuously integrated with the other surface of the electrolyte is laminated Fuel cell,
The separator has a frame member that has a fuel gas communication hole, an oxidant gas communication hole, and a cooling medium communication hole formed in the outer peripheral portion in the stacking direction of the separator;
In the frame member, a plurality of conductive members that are maintained in an insulated state and provided in the region of the electrode reaction surface;
With
A gas flow path through which the fuel gas or oxidant gas passes is formed along the electrode reaction surface in the plurality of conductive members ,
The plurality of conductive members of the separator stacked on the anode side electrode and the plurality of conductive members of the separator stacked on the cathode side electrode sandwich the electrolyte / electrode structure. It is opposed to the symmetrical positions to each other, and a fuel cell, characterized in that that are respectively connected to the measuring means for measuring the impedance between the conductive member with each other to face each other.   2. The fuel cell according to claim 1, wherein the conductive member is arranged in a lattice shape with a nonconductive member interposed in the frame member.

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