Current density distribution control apparatus and fuel battery

Abstract

This current density distribution control apparatus for controlling the current density distribution of a fuel battery in which a plurality of fuel battery cells are stacked comprises a current control device disposed in each of a plurality of regions resulting from dividing a power generation region of the fuel battery, the current control apparatus having a current measurement unit that measures a current value in the region. The current density distribution control apparatus has an electronic load device that controls a current value of output current on the basis of the current value measured by the current measurement unit, and a heat transfer structure for guiding heat of the electronic load device to a cooling water flow path provided in a separator of the fuel battery cells.

Description

Current density distribution control device and fuel cell

[0001] The present disclosure relates to a current density distribution control device and a fuel cell.

[0002] For example, in order to suppress deterioration of a fuel cell stack, it has been conventionally practiced to measure the current density distribution on the surface of a fuel cell unit. For example, Patent Document 1 describes a method in which a current density distribution control device (an anode-side current distribution measuring device and a cathode-side current distribution measuring device) equipped with a plurality of divided current collectors is inserted between single fuel cell units, and the current density distribution is measured based on the current value of the current flowing through each divided current collector.

[0003] Japanese Patent Application Laid-Open No. 2007-87859

[0004] However, in the current density distribution control device (anode-side current distribution measuring device and cathode-side current distribution measuring device) described in Patent Document 1, an electronic load device and a voltage measuring device are provided on each of the multiple divided current collectors that measure the current density distribution, which can cause the temperature of the current density distribution control device to rise, and ultimately the temperature of the fuel cell stack to rise excessively. If the temperature of the fuel cell stack rises excessively, for example, the internal materials of the fuel cell cells can corrode or deteriorate, causing problems such as a shortened lifespan of the fuel cell stack.

[0005] The present disclosure has been made in consideration of the above circumstances, and an object of the present disclosure is to provide a current density distribution control device that suppresses excessive temperature rise, and a fuel cell equipped with such a current density distribution control device.

[0006] In order to solve the above problems, according to one aspect of the present disclosure, there is provided a current density distribution control device that controls the current density distribution of a fuel cell in which multiple fuel cell cells are stacked, the current density distribution control device comprising a current control device arranged in each of multiple regions divided within the power generation area of ​​the fuel cell, the current control device having a current measurement unit that measures the current value in the region, an electronic load device that controls the current value of the output current based on the current value measured by the current measurement unit, and a heat transfer structure that directs heat from the electronic load device to a cooling water flow path provided in the separator of the fuel cell.

[0007] As described above, according to the present disclosure, it is possible to provide a current density distribution control device in which an excessive temperature rise is suppressed, and a fuel cell including the current density distribution control device.

[0008] Fig. 1 is a diagram schematically showing an example of the configuration of a fuel cell stack according to an embodiment; Fig. 2 is an exploded perspective view showing an example of the configuration of a fuel cell stack; Fig. 3 is a plan view of a current density distribution control device; Fig. 4 is an enlarged cross-sectional view of a current density distribution control device; Fig. 5 is a diagram showing an example of an electronic load circuit mounted on an electronic load device; Fig. 6 is a plan view of a current density distribution control device according to a second embodiment; Fig. 7 is an enlarged cross-sectional view of a current density distribution control device according to a third embodiment;

[0009] 1. Embodiments Preferred embodiments of the present disclosure will be described below with reference to the accompanying drawings. Note that the dimensions and scale of each part in the drawings may differ from the actual dimensions. The drawings may also be shown schematically to facilitate understanding. Furthermore, the scope of the present disclosure is not limited to the following exemplary embodiments unless otherwise specified to limit the present disclosure.

[0010] In the following description, mutually orthogonal X-axis, Y-axis, and Z-axis are defined. The X-axis, Y-axis, and Z-axis are three mutually orthogonal axial directions, and are common to all drawings described below. As illustrated in FIG. 1 , one direction along the X-axis as viewed from an arbitrary point is denoted as the X1 direction, and the direction opposite to the X1 direction is denoted as the X2 direction. The X-axis direction is a direction that includes both the X1 direction and the X2 direction. Similarly, mutually opposite directions along the Y-axis from an arbitrary point are denoted as the Y1 direction and the Y2 direction. The Y-axis direction is a direction that includes both the Y1 direction and the Y2 direction. Furthermore, mutually opposite directions along the Z-axis from an arbitrary point are denoted as the Z1 direction and the Z2 direction. The Z-axis direction (stacking direction) is a direction that includes both the Z1 direction and the Z2 direction.

[0011] [First embodiment] <Configuration of fuel cell> Fig. 1 is a diagram schematically showing an example configuration of a fuel cell stack 100 (fuel cell) according to this embodiment. As shown in Fig. 1, the fuel cell stack 100 has a current density distribution control device 1 and a plurality of fuel cell units 20. The plurality of fuel cell units 20 are stacked in the Z-axis direction, and the current density distribution control device 1 is interposed between the fuel cell units 20.

[0012] The fuel cell stack 100 has a power generation area E. The power generation area E is made up of the power generation regions of the multiple fuel cell units 20 stacked in the Z-axis direction. As shown in FIG. 1 , the power generation area E is divided into multiple areas E1 in a lattice pattern.

[0013] (Fuel Cell) FIG. 2 is an exploded perspective view showing an example of the configuration of a fuel cell stack 100. The fuel cell 20 is a stacked structure in which a membrane electrode assembly (MEA) is sandwiched between a pair of separators 21, and is a solid polymer fuel cell that generates electricity by chemically reacting hydrogen and oxygen. The membrane electrode assembly has a fuel electrode 22 (anode), a polymer electrolyte membrane 23, and an air electrode 24 (cathode). Note that the fuel cell stack 100 according to this embodiment typically has three or more fuel cell cells 20 stacked, but for ease of explanation, FIG. 2 shows only two fuel cell cells 20. Furthermore, in FIG. 2, elements (e.g., end plates) other than the fuel cell cells 20 and the current density distribution control device 1 that constitute the fuel cell stack 100 are not shown.

[0014] The separator 21 extends in the Y-axis direction and has a plurality of grooves 21t arranged at predetermined intervals in the X-axis direction. １ and a plurality of grooves 21t extending in the X-axis direction and arranged at predetermined intervals in the Y-axis direction. ２ The plurality of grooves 21t ２ The grooves 21t have the function of guiding oxygen to the air electrode 24 and discharging the generated water to the outside. １has a function of directing hydrogen to the fuel electrode 22. The separator 21 also has a plurality of cooling water flow paths 211 extending in the X-axis direction and arranged at predetermined intervals in the Y-axis direction (see FIG. 4). There are no particular restrictions on the material that constitutes the separator 21, and for example, a carbon material or a metal material may be used.

[0015] The anode 22 has an anode catalyst layer 222 and a gas diffusion layer 221. The anode catalyst layer 222 is a membrane containing carbon black powder supporting platinum (Pt), which functions as a catalyst, and an ionomer. The cathode 24 has an anode catalyst layer 241 and a gas diffusion layer 242. Like the anode catalyst layer 222, the anode catalyst layer 241 is a membrane containing carbon black powder supporting platinum (Pt), which functions as a catalyst, and an ionomer.

[0016] In the fuel cell 20 according to this embodiment, the separator 21 on the fuel electrode 22 side has a plurality of grooves 21t １ When hydrogen is supplied to the anode, the hydrogen is diffused through the gas diffusion layer 221 and reaches the anode catalyst layer 222. In the anode catalyst layer 222, the hydrogen is oxidized to generate protons (H ２ →2H ＋ +2e － The protons pass through the polymer electrolyte membrane 23 and enter the air electrode catalyst layer 241. On the other hand, the protons pass through the plurality of grooves 21t of the separator 21 on the air electrode 24 side. ２ Air (oxygen) is supplied to the cathode 22. This air enters the cathode catalyst layer 241 while being diffused by the gas diffusion layer 242. In the cathode catalyst layer 241, protons supplied from the anode 22 react with oxygen to generate water (2H ＋ +1 / 2O ２ +2e － →H ２ O) In the fuel cell 20, such an electrochemical reaction generates a voltage between the air electrode 24 and the fuel electrode 22.

[0017] (Current Density Distribution Control Device) FIG. 3 is a plan view of the current density distribution control device 1. The current density distribution control device 1 is a sensor plate formed by stacking a plurality of current control devices 11 and a plurality of insulating layers 12 (see FIG. 4) made of an insulating material such as epoxy resin. As shown in FIG. 3, each of the plurality of current control devices 11 is disposed in a respective one of a plurality of regions E1. The current density distribution control device 1 according to this embodiment can smooth the current density distribution on the surface of the fuel cell 20 to some extent by controlling the current value of the output current I (see FIGS. 4 and 5) of the current control device 11 for each region E1. Note that the "current density distribution" mentioned above refers to the distribution of current density for each region E1 on the surface of the fuel cell 20, and the current density in region E1 is calculated, for example, by the following formula (1):

[0018] Current density [A / m ２ ] = Current value [A] of output current I of current control device 11 in region E1 / Area of ​​region E1 [m ２ ]・・・(1)

[0019] The current density distribution control device 1 has an enclosure 10E, which is an area that surrounds the power generation region E when the current density distribution control device 1 is viewed in the stacking direction of the fuel cell 20. The enclosure 10E may be provided with a through-hole 10H and a communication connector C, as shown in FIG. 3 . The through-hole 10H functions as a hole through which, for example, hydrogen and air (oxygen) used for power generation in the fuel cell 20, or cooling water that cools the fuel cell stack 100, passes. The communication connector C is an input / output interface that is connected to each of the multiple current control devices 11 and an external device (not shown). The current density distribution control device 1 may exchange various types of data with the external device connected via the communication connector C.

[0020] 4 is an enlarged cross-sectional view of the current density distribution control device 1, showing an example of the configuration of the current control device 11 arranged in the region E1. The current control device 11 has an electronic load device 110, electrode pads 111 and 112, a heat transfer structure 113, and a conductive structure 114.

[0021] The electrode pad 111 is provided on the insulating layer 121. The electrode pad 111 is exposed from the surface of the insulating layer 121 facing the Z2 direction and abuts against the separator 21. The electrode pad 112 is provided on the insulating layer 123. The electrode pad 112 is exposed from the surface of the insulating layer 123 facing the Z1 direction and abuts against the separator 21.

[0022] The conductive structure 114 includes a via 114v １ ~Via 114v ４ and copper foil pattern 114P １ , 114P ２ (wiring) and copper foil pattern 114P １ is a via 114v provided in the insulating layer 123. １ and via 114v １ 114P. １ is the terminal 110T of the electronic load device 110 １ Copper foil pattern 114P ２ via 114v ２ and via 114v ２ , via 114v provided in the insulating layer 122 ３ , and vias 114v provided in the insulating layer 121 ４ 114P. ２ is the terminal 110T of the electronic load device 110 ２ is connected to.

[0023] Since the conductive structure 114 has the above-described configuration, the electrode pad 111 is electrically connected to the electrode pad 112 via the conductive structure 114 and the electronic load device 110. As a result, the current output from one of the fuel cell cells 20 is transmitted in order through the electrode pad 112 and the via 114v. １ , copper foil pattern 114P １ , electronic load device 110, copper foil pattern 114P ２ , via 114v ２ ~Via 114v ４ and flows to the other fuel cell 20 via the electrode pad 111. In Fig. 4, the flow of current from one fuel cell 20 to the other fuel cell 20 is indicated by a dotted arrow.

[0024] The heat transfer structure 113 includes a heat sink 113h and a copper foil pattern 113P. １ , 113P ２ and a plurality of vias 113v １ And via 113v ２ The heat sink 113h is provided on the electronic load device 110. The copper foil pattern 113P １ are provided on the surface of the insulating layer 122 facing the Z1 direction and abut against the heat sink 113h. １ is provided on the insulating layer 122, and the copper foil pattern 113P １ Copper foil pattern 113P ２ is provided on the insulating layer 121. ２ are exposed from the surface of the insulating layer 121 facing the Z1 direction, and a plurality of vias 113v １ Connected to via 113v ２ is provided on the insulating layer 121, and the copper foil pattern 113P ２ and the electrode pad 111 .

[0025] Since the heat transfer structure 113 has the above-described configuration, the heat generated by the electronic load device 110 is transferred to the heat sink 113h, the copper foil pattern 113P, and the １ , a plurality of vias 113v １ , copper foil pattern 113P ２ , via 113v ２ and the electrode pads 111, and then the heat is conducted to the separator 21. The heat conducted to the separator 21 is released to the cooling water flow path 211 provided in the separator 21. In the fuel cell 20 of this embodiment, the heat generated by the electronic load device 110 is conducted to the separator 21 via the heat transfer structure 113, and the heat conducted to the separator 21 is released to the cooling water in the cooling water flow path 211. This suppresses an excessive temperature rise in the electronic load device 110, and ultimately suppresses an excessive temperature rise in the current density distribution control device 1 having a plurality of current control devices 11. In FIG. 4, the heat conduction path of the heat generated by the electronic load device 110 is indicated by solid arrows.

[0026] 5 is a diagram showing an example of an electronic load circuit 110A mounted on the electronic load device 110. The electronic load device 110 according to this embodiment is, for example, a control circuit board having one or more electronic load circuits 110A shown in FIG. 5. The electronic load device 110 further includes a central processing unit (hereinafter referred to as a CPU) that controls part or all of the electronic load device 110, a ROM storing programs and the like, a RAM serving as a work area for the CPU, a variable power supply 110e, and a current measuring unit 110d. The electronic load device 110 may employ a processing circuit such as a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), or an FPGA (Field-Programmable Gate Array) instead of or in addition to the CPU.

[0027] The electronic load circuit 110A includes an operational amplifier 110a, a heat-generating element 110b such as a field effect transistor (FET), and a shunt resistor 110c. As shown in FIG. 5, the non-inverting input terminal (+) of the operational amplifier 110a is connected to a variable power supply 110e, and the inverting input terminal (-) is connected between the shunt resistor 110c and the heat-generating element 110b. This connection allows a constant current (output current I) to flow through the shunt resistor 110c, causing the shunt resistor 110c to function as a constant-current load. In the electronic load circuit 110A shown in FIG. 5, the operational amplifier 110a operates to maintain the non-inverting input terminal (+) and the inverting input terminal (-) at the same potential. In other words, the operational amplifier 110a operates to maintain an imaginary short circuit. As a result, when the CPU changes the voltage of variable power supply 110e, the output voltage of operational amplifier 110a changes so as to maintain the imaginary short of operational amplifier 110a, and the current value of output current I becomes proportional to the output voltage of operational amplifier 110a. Specifically, as the voltage of variable power supply 110e increases, the output voltage of operational amplifier 110a increases, and the current value of output current I also increases, and as the voltage of variable power supply 110e decreases, the output voltage of operational amplifier 110a decreases, and the current value of output current I also decreases.

[0028] The current measuring unit 110d detects the potential difference (voltage drop) across the shunt resistor 110c and measures the current value of the output current I based on Ohm's law. The current measuring unit 110d outputs information about the measurement results measured in this manner to the CPU. The current measuring unit 110d is, for example, a detection circuit equipped with a current sensor that measures the current value of the output current I. However, the current measuring unit 110d is not particularly limited as long as it can measure the current value of the output current I and output information about the measurement results to the CPU. For example, the current measuring unit 110d is not limited to a resistance detection type measuring device that uses a shunt resistor, and a magnetic field detection type measuring device, for example, may also be used.

[0029] The variable power supply 110e changes its voltage under the control of the CPU, which acquires information on the measurement results from the current measurement unit 110d. Specifically, for example, the CPU increases the voltage of the variable power supply 110e when it determines that the current value of the output current I measured by the current measurement unit 110d is smaller than a predetermined threshold T1, and decreases the voltage of the variable power supply 110e when it determines that the current value of the output current I measured by the current measurement unit 110d is greater than a predetermined threshold T2 (T2 > T1). The current density distribution control device 1 according to this embodiment performs such current amount control of the output current I for each region E1, thereby suppressing bias in the current density for each region E1 and smoothing the current density distribution on the surface of the fuel cell 20, thereby suppressing deterioration of the fuel cell stack 100.

[0030] As described above, the current density distribution control device 1 of this embodiment is a current density distribution control device that controls the current density distribution of a fuel cell stack 100 in which a plurality of fuel cell cells 20 are stacked, and is equipped with a current control device 11 arranged in each of a plurality of regions E1 divided within the power generation region E of the fuel cell stack 100, and the current control device 11 has a current measurement unit 110d that measures the current value in the region E1, an electronic load device 110 that controls the current value of the output current I based on the current value measured by the current measurement unit 110d, and a heat transfer structure 113 that guides heat from the electronic load device 110 to a cooling water flow path 211 provided in the separator 21 of the fuel cell 20.

[0031] 5 , heat generated by the electronic load device 110 is transferred to the separator 21 via the heat transfer structure 113, and the heat transferred to the separator 21 is released into the cooling water in the cooling water flow path 211. This prevents an excessive temperature rise in the electronic load device 110, and ultimately prevents an excessive temperature rise in the current density distribution control device 1 having a plurality of current control devices 11.

[0032] 6 is a plan view of a current density distribution control device 2 according to a second embodiment. The current density distribution control device 2 according to the second embodiment differs from the first embodiment in that it includes a heat dissipation member arranged to surround the power generation region. In the following description of the second embodiment, the same components as those in the first embodiment are designated by the same reference numerals, and their description will be omitted or simplified.

[0033] The current density distribution control device 2 has a plurality of heat dissipation members 103. As shown in FIG. 6 , the plurality of heat dissipation members 103 are arranged in an enclosure 10E so as to surround the power generation area E. The heat dissipation members 103 are rectangular plate members when viewed in the Z1 direction, and are made of a metal material such as copper or gold. Note that the metal material constituting the heat dissipation members 103 is not limited to copper or gold, and is not particularly limited as long as it has heat dissipation properties (thermal conductivity).

[0034] 7 is an enlarged cross-sectional view of a fuel cell stack including a current density distribution control device 2, showing an example of the configuration of a current control device 101 according to the second embodiment arranged in region E1. The current control device 101 has an electronic load device 110, electrode pads 111 and 112, a conductive structure 114, and a heat transfer structure 102. The current control device 101 has the same configuration as the current control device 11 of the first embodiment, except that the heat transfer structure 102 is different from the heat transfer structure 113 of the first embodiment.

[0035] The heat transfer structure 102 includes a heat sink 113h and a copper foil pattern 113P. １ and a plurality of vias 113v １ The copper foil pattern 102P is provided on the insulating layer 121 and is a wiring extending in the Y-axis direction from the region E1 to the surrounding portion 10E. The copper foil pattern 102P has a plurality of vias 113v.１ The plurality of vias 102v are provided in the insulating layer 121 and connected to the copper foil pattern 102P. The heat dissipation member 103 is provided in the insulating layer 121 and connected to the plurality of vias 102v. The heat dissipation member 103 is exposed from the surface of the insulating layer 121 facing the Z2 direction and abuts against the separator 21.

[0036] Since the heat transfer structure 102 has the configuration shown in FIG. 7, the heat generated by the electronic load device 110 is transferred to the heat sink 113h, the copper foil pattern 113P, and the like. １ , a plurality of vias 113v １ , the copper foil pattern 102P, and the plurality of vias 102v to the heat dissipation member 103. The heat transferred to the heat dissipation member 103 is transferred to the separator 21 and dissipated to the cooling water in the cooling water flow path 211 provided in the separator 21. In the second embodiment, the heat generated by the electronic load device 110 is transferred to the heat dissipation member 103 via the heat transfer structure 102, and the heat transferred to the separator 21 via the heat dissipation member 103 is dissipated to the cooling water flow path 211. This suppresses an excessive temperature rise in the electronic load device 110, and ultimately suppresses an excessive temperature rise in the current density distribution control device 2 having a plurality of current control devices 101. Note that in FIG. 7, the heat transfer path of the heat generated by the electronic load device 110 is indicated by solid arrows.

[0037] 8 is an enlarged cross-sectional view of a fuel cell stack including a current density distribution control device 3 according to a third embodiment, and shows an example of the configuration of a current control device 201 of the third embodiment arranged in region E1. In the following description of the third embodiment, the same components as those in the first and second embodiments are denoted by the same reference numerals, and their description will be omitted or simplified.

[0038] The current control device 201 includes an electronic load device 110, electrode pads 111 and 112, a conductive structure 114, and a heat transfer structure 202. The current control device 201 has the same configuration as the current control device 101 of the second embodiment, except that the heat transfer structure 202 is different from the heat transfer structure 102 of the second embodiment.

[0039] The heat transfer structure 202 includes a heat sink 113h and a copper foil pattern 113P. １ and a plurality of vias 113v１ The via 201v is provided in the insulating layer 121 and is connected to the electrode pad 111 and the copper foil pattern 102P.

[0040] Since the heat transfer structure 202 has the configuration shown in FIG. 8, the heat generated by the electronic load device 110 is transferred in the order of the heat sink 113h, the copper foil pattern 113P, and the like. １ , a plurality of vias 113v １ , and is conducted to the copper foil pattern 102P. The heat conducted to the copper foil pattern 102P is conducted not only to the heat dissipation member 103 through the multiple vias 102v, but also to the electrode pad 111 through the vias 201v. The heat conducted to the electrode pad 111 and the heat dissipation member 103 is conducted to the separator 21, and the heat conducted to the separator 21 is dissipated to the cooling water flow path 211 provided in the separator 21. This allows the heat of the electronic load device 110 to be dissipated to the cooling water flow path 211 more efficiently than in a configuration in which the heat of the electronic load device 110 is conducted to either the electrode pad 111 or the heat dissipation member 103 alone. This further suppresses excessive temperature rise in the electronic load device 110, and ultimately suppresses excessive temperature rise in the current density distribution control device 3 having multiple current control devices 101. Note that in FIG. 8, the heat conduction path of the heat generated by the electronic load device 110 is indicated by solid arrows.

[0041] While the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and various modifications may be made. The above-described embodiments may employ one or more aspects exemplified below.

[0042] [Variation 1] In the above embodiment, the heat dissipation member 103 is provided in the surrounding portion 10E of the current density distribution control device 2, but this is not limited to this. For example, the heat dissipation member 103 may be provided between the electrode pads 111 in the power generation area E, and the arrangement of the heat dissipation member 103 is not limited to the form shown in Fig. 6. By providing the heat dissipation member 103 between the electrode pads 111, the current density distribution control device 2 can be made compact while maintaining the heat dissipation performance of the electronic load device 110.

[0043] [Modification 2] In the above embodiment, the fuel cell 20 is a polymer electrolyte fuel cell, but is not limited to this and may be, for example, a phosphoric acid fuel cell, a molten carbonate fuel cell, a solid oxide fuel cell, or an alkaline fuel cell.

[0044] [Modification 3] In the above embodiment, each of the multiple current control devices is provided with a CPU, but this is not limited to this. For example, a single control device that functions similarly to the CPU in the above embodiment may be disposed outside the fuel cell stack, and this control device may control each of the multiple current control devices via the communication connector C in the same manner as the CPU in the above embodiment.

[0045] 3. Supplementary Note: The fuel cell stacks exemplified in the above-described embodiments are typically applied to automobiles, but are not limited thereto, and the applications of the present disclosure are not particularly limited. The fuel cell stacks of the present disclosure are not limited to automobiles, and may be used, for example, as primary or backup power sources in commercial facilities, industrial facilities, homes, etc., and may also be used as power sources for forklifts, buses, trains, boats, motorcycles, submarines, etc.

[0046] Furthermore, the effects described in this specification are merely descriptive or exemplary and are not limiting. In other words, the present invention may exhibit other effects that will be apparent to those skilled in the art from the description of this specification, in addition to or in place of the above-described effects.

[0047] Although the preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings, the technology of the present disclosure is not limited to the above-described embodiments. It is clear that a person skilled in the art of the technology to which the present disclosure pertains can conceive of various modified or altered examples within the scope of the technical ideas described in the claims, and it is understood that these also naturally fall within the technical scope of the present disclosure.

[0048] 4. Supplementary Notes The following aspects can be understood from the above-described exemplary embodiments.

[0049] A current density distribution control device according to one aspect (aspect 1) of the present disclosure is a current density distribution control device that controls the current density distribution of a fuel cell in which multiple fuel cell cells are stacked, and is equipped with a current control device arranged in each of multiple regions divided within the power generation area of ​​the fuel cell, and the current control device has a current measurement unit that measures the current value in the region, an electronic load device that controls the current value of the output current based on the current value measured by the current measurement unit, and a heat transfer structure that directs heat from the electronic load device to a cooling water flow path provided in the separator of the fuel cell.

[0050] According to the first aspect, heat generated by the electronic load device is transferred to the separator via the heat transfer structure, and the heat transferred to the separator is released to the cooling water flow path, thereby suppressing an excessive temperature rise in the electronic load device and, in turn, suppressing an excessive temperature rise in a current density distribution control device having multiple current control devices.

[0051] A current density distribution control device according to a specific example (aspect 2) of aspect 1 further includes an enclosing portion that surrounds the power generation area when viewed in the stacking direction of the fuel cell, and a heat dissipation member arranged in the enclosing portion, connected to the heat transfer structure, and abutting the separator.

[0052] According to aspect 2, heat generated by the electronic load device is transferred to the heat dissipation member via the heat transfer structure, and the heat transferred to the separator via the heat dissipation member is released to the cooling water flow path, thereby suppressing an excessive temperature rise in the electronic load device and, ultimately, suppressing an excessive temperature rise in a current density distribution control device having multiple current control devices.

[0053] In the current density distribution control device according to a specific example (aspect 3) of aspect 2, the heat dissipation member is made of a metal material having heat dissipation properties.

[0054] The current control device according to a specific example (Aspect 4) of Aspect 2 further includes an electrode pad connected to the heat transfer structure and in contact with the separator.

[0055] According to aspect 4, heat generated by the electronic load device is transferred to the heat dissipation member and the electrode pad via the heat transfer structure, and the heat transferred to the separator via the heat dissipation member and the electrode pad is released to the coolant flow path. This allows the heat from the electronic load device to be released to the coolant flow path more efficiently than in an aspect in which the heat from the electronic load device is transferred to either the electrode pad or the heat dissipation member. This further suppresses excessive temperature rise in the electronic load device, and ultimately further suppresses excessive temperature rise in a current density distribution control device having multiple current control devices.

[0056] A fuel cell according to one aspect (aspect 5) of the present disclosure includes the current density distribution control device according to any one of aspects 1 to 4 above.

[0057] According to aspect 5, heat generated by the electronic load device is transferred to the separator via the heat transfer structure, and the heat transferred to the separator is released to the cooling water flow path, thereby suppressing an excessive temperature rise in the current density distribution control device and, ultimately, in the fuel cell.

[0058] DESCRIPTION OF SYMBOLS 1, 2, 3... Current density distribution control device 11, 101, 201... Current control device 20... Fuel cell 21... Separator 100... Fuel cell stack (fuel cell) 102, 113, 202... Heat transfer structure 103... Heat dissipation member 110... Electronic load device 110d... Current measurement unit 211... Cooling water flow path

Claims

1. A current density distribution control device that controls the current density distribution of a fuel cell in which multiple fuel cell cells are stacked, comprising: a current control device arranged in each of multiple regions divided within the power generation area of ​​the fuel cell, the current control device having: a current measurement unit that measures the current value in the region; an electronic load device that controls the current value of the output current based on the current value measured by the current measurement unit; and a heat transfer structure that directs heat from the electronic load device to a cooling water flow path provided in the separator of the fuel cell.

2. The current density distribution control device according to claim 1, further comprising: an enclosing portion that encloses the power generation area when viewed in the stacking direction of the fuel cell cells; and a heat dissipation member arranged in the enclosing portion, connected to the heat transfer structure, and abutting against the separator.

3. The current density distribution control device according to claim 2, wherein the heat dissipation member is made of a metal material having heat dissipation properties.

4. The current density distribution control device according to claim 2, wherein the current control device further comprises an electrode pad connected to the heat transfer structure and abutting against the separator.

5. A fuel cell equipped with a current density distribution control device according to any one of claims 1 to 4.

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