JP5487883B2 - Fuel cell system and refrigerant charging method - Google Patents

Description

  The present invention relates to a fuel cell cooling technique.

  In a fuel cell system that generates power using a fuel cell, a cooling device that controls the operating temperature of the fuel cell is usually provided. As shown in FIG. 15, the cooling device is generally of a type in which a refrigerant, for example, water is circulated between the fuel cell and the radiator. In such a cooling device, since the piping for circulating the refrigerant is sufficiently electrically insulated from the fuel cell, the insulation resistance between the fuel cell and the ground is between them as shown in FIG. It is ensured by the resistance value of the refrigerant in the sections S1 and S2, which are the corresponding refrigerant paths. For this reason, in the cooling device, it is necessary to always suppress the conductivity of the refrigerant to a predetermined value or less according to the distance between the fuel cell and the ground. As the distance between the fuel cell and the ground becomes shorter, the predetermined value becomes smaller. In view of this, a technique for removing ions eluted into the refrigerant from the core or piping of the radiator as required has been developed (for example, Patent Document 1 below).

  However, the technique of Patent Document 1 removes ions eluted in the refrigerant during the operation of the fuel cell system performed after the cooling device is filled with the refrigerant. Since the radiator has a large surface area in contact with the cooling water, it has a greater influence on ion elution than other pipes, and most of the ion elution is initial elution. Therefore, in the technique of Patent Document 1, when the distance between the fuel cell and the ground cannot be secured long due to the restriction of the arrangement of the fuel cell system, the refrigerant at the initial use of the fuel cell system (when operating for the first time). There was a possibility that the electrical conductivity of the glass could not be reduced below a predetermined value. In such a case, it is necessary to provide a cleaning process for the radiator in the manufacturing stage of the fuel cell system to suppress elution of ions during the initial use of the radiator. Such a cleaning process requires a long time, and a technique capable of shortening the cleaning time or omitting the cleaning process has been desired.

JP 2007-311087 A

  In view of at least a part of the above-described problems, the problem to be solved by the present invention is to suppress an increase in the conductivity of the refrigerant during the initial use of the fuel cell system.

  The present invention has been made to solve the above-described problems, and can be realized as the following forms or application examples.

Application Example 1 A fuel cell system including a fuel cell and a cooling system for cooling the fuel cell with a liquid refrigerant, wherein the cooling system cools the refrigerant by exchanging heat with the refrigerant. And a radiator provided with an inlet for injecting the refrigerant from outside the cooling system, a supply channel for guiding the refrigerant flowing through the core from the radiator to the fuel cell, and the refrigerant A discharge flow path that leads from the fuel cell to the radiator; and an ion exchanger that is provided on the flow path of the refrigerant and removes ions contained in the refrigerant; the radiator, the supply flow path, and the discharge flow The cooling system after at least a part of the refrigerant injected into the passage, the ion exchanger and the fuel cell from the inlet and filled in the cooling system flows in the order of the core and the ion exchanger. In Fuel cell system is arranged in a positional relationship to be Hama.

  The fuel cell system having such a configuration is configured so that at least a part of the refrigerant injected from the inlet of the radiator flows in the order of the core and the ion exchanger and is then charged into the cooling system in a positional relationship. Etc. are arranged. Therefore, when the refrigerant is charged into the cooling system, ions can be initially eluted from the core into the refrigerant, and the eluted ions can be removed by the ion exchanger, and the conductivity of the refrigerant during initial use of the fuel cell system can be reduced. The rise can be suppressed. In addition, since the increase in the conductivity of the refrigerant can be suppressed by the refrigerant filling process that is absolutely necessary in the manufacturing process of the fuel cell system, it is efficient.

Application Example 2 The fuel cell system according to Application Example 1, wherein at least one of the paths from the radiator to the ion exchanger and the ion exchanger are arranged at a lower position in the direction of gravity than the fuel cell.
Application Example 3 The fuel cell system according to Application Example 1 or Application Example 2, in which at least one of the paths from the radiator to the ion exchanger is formed with a downward slope.

  In the fuel cell systems of application example 2 and application example 3, the refrigerant injected from the inlet and circulated through the core can be more easily guided to the ion exchanger side than the fuel cell side, so that an increase in the conductivity of the refrigerant is suppressed. be able to.

[Application Example 4] The fuel cell system according to any one of Application Examples 1 to 3, further comprising: a refrigerant connected to the supply flow path and flowing from the fuel cell side to the radiator side. A fuel cell system provided with a core bypass flow path that leads to the supply flow path in a path that bypasses the flow path, wherein the ion exchanger is provided on the core bypass flow path.

  In the fuel cell system having such a configuration, the refrigerant flow path includes a path that circulates between the core and the fuel cell, and a path that circulates between the ion exchanger and the fuel cell. That is, since the refrigerant does not flow through both the core and the ion exchanger, it is possible to suppress pressure loss in the refrigerant flow. Moreover, if it is set as the structure which switches the distribution route of a refrigerant | coolant according to the ion concentration in a refrigerant | coolant, an ion exchanger can be extended in lifetime. Moreover, if it is set as the structure which switches the distribution route of a refrigerant | coolant according to the operating temperature of a fuel cell system, the ion removal in a refrigerant | coolant can be performed within the heat resistant range of an ion exchanger.

Application Example 5 Of the core bypass channel, a path from the end opposite to the connection point between the core bypass channel and the supply channel to the ion exchanger, the ion exchanger, Is a fuel cell system according to Application Example 4, which is disposed at a position lower than the fuel cell in the direction of gravity.
[Application Example 6] The application example in which the core bypass flow path is formed so that the path from the end opposite to the connection point between the core bypass flow path and the supply flow path to the ion exchanger is formed with a downward slope. The fuel cell system according to Example 4 or Application Example 5.

  In the fuel cell systems of Application Example 5 and Application Example 6, the refrigerant injected from the inlet and circulated through the core can be easily guided to the ion exchanger side via the core bypass flow path. Can be suppressed.

Application Example 7 In the fuel cell system according to any one of Application Examples 4 to 6, the radiator includes a first tank and a second tank arranged on both sides of the core. The first tank includes the inlet and a supply opening that is an opening connected to the supply flow path, and the second tank is an opening connected to the discharge flow path. A discharge opening and a bypass opening that is an opening connected to the core bypass flow path, and the supply opening and the discharge opening are arranged in the direction of gravity in the gravity direction and the bypass. The fuel cell system disposed between the opening for use.

  In the fuel cell system having such a configuration, the refrigerant injected from the inlet of the first tank can flow through the core and be led to the bypass opening of the second tank. Moreover, since the supply opening and the discharge opening are arranged between the inlet and the bypass opening in the direction of gravity, that is, the bypass opening is the supply opening and the discharge opening. Therefore, the refrigerant can be easily guided to the core bypass flow path via the bypass opening, and can also be easily guided to the ion exchanger disposed ahead of the core bypass flow path.

[Application Example 8] The fuel cell system according to any one of Application Example 4 to Application Example 6, wherein the radiator includes a first tank and a second tank arranged on both sides of the core. The first tank includes the inlet and a supply opening that is an opening connected to the supply flow path, and the second tank is an opening connected to the discharge flow path. A discharge opening, the discharge opening is provided at a lower position in the direction of gravity than the supply opening, and the core bypass flow path is a connection between the core bypass flow path and the supply flow path. A fuel cell system having an end opposite to the point connected to the discharge channel.

  In the fuel cell system having such a configuration, the refrigerant injected from the inlet of the first tank can flow through the core and be guided to the discharge opening of the second tank. In addition, since the discharge opening is provided at a position lower in the direction of gravity than the supply opening, the refrigerant can be easily guided to the discharge flow path through the discharge opening and is connected to the discharge flow path. It becomes easy to guide also to the core bypass flow path and the ion exchanger arranged ahead.

[Application Example 9] The fuel cell system according to Application Example 7 or Application Example 8, further provided at a connection point between the supply flow path and the core bypass flow path, wherein the core and the ion exchanger are provided. A three-way valve that adjusts the flow rate of the flowing refrigerant, and the three-way valve is a fuel that enables communication between the core bypass passage and the passage on the radiator side of the three-way valve in the supply passage. Battery system.

  In the fuel cell system having such a configuration, when the refrigerant is injected in a state where the three-way valve is in communication with the core bypass passage and the passage on the radiator side of the three-way valve in the supply passage, the Bernoulli effect and Due to the ejector effect, air is drawn from the supply channel side to the first tank side, so that it is difficult for the injected refrigerant to flow into the supply channel side through the supply opening. Therefore, the injected refrigerant can be easily guided to the core bypass flow path and the ion exchanger ahead thereof through the core, the second tank, and the bypass opening. In addition, since air is drawn from the supply channel, the refrigerant guided to the ion exchanger is easily guided to the path from the ion exchanger to the radiator side via the three-way valve. Therefore, the amount of refrigerant flowing through the ion exchanger can be increased.

[Application Example 10] In the application example 9, the injection port includes a protrusion protruding in the direction of narrowing the flow width in the direction crossing the flow direction of the refrigerant injected from the injection port inside the injection port. Fuel cell system.

  In the fuel cell system having such a configuration, the flow width of the refrigerant to be injected can be narrowed by the protrusion, so that the flow rate of the injected refrigerant can be increased. As a result, the effect of the application example 9 can be enhanced by the Bernoulli effect and the ejector effect.

[Application Example 11] The fuel cell system according to any one of Application Example 4 to Application Example 10, wherein the discharge flow path is a connection point between the core bypass flow path and the supply flow path in the core bypass flow path. Between the end opposite to the fuel cell and the fuel cell to prevent the refrigerant from flowing in the direction from the radiator side to the fuel cell side, or A fuel cell system including a backflow prevention unit that blocks distribution.

  In the fuel cell system having such a configuration, the backflow prevention unit can prevent the refrigerant from flowing from the radiator side to the fuel cell side or can prevent the refrigerant from flowing because of the non-electrically operating structure. The system can be operated even when the refrigerant is charged into the system. Therefore, during the refrigerant filling operation, the refrigerant is prevented from flowing into the fuel cell from the discharge flow path through a route that does not pass through the core bypass flow passage, that is, a route that does not pass through the ion exchanger. Therefore, the quantity of the refrigerant | coolant with which it distribute | circulates a core and also distribute | circulates an ion exchanger can be increased.

Application Example 12 In the ion exchanger, the distance on the path from the end opposite to the connection point between the core bypass flow channel and the supply flow channel to the ion exchanger is 12. The fuel cell system according to any one of Application Example 4 to Application Example 11, which is provided at a position shorter than a distance on a path to the exchanger.

  In the fuel cell system having such a configuration, the distance on the path from the end opposite to the connection point between the core bypass flow path and the supply flow path to the ion exchanger is shortened. Can make it easier to guide.

[Application Example 13] The fuel cell system according to any one of Application Example 1 to Application Example 3, wherein the ion exchanger is provided on the discharge flow path, and is further connected in parallel to the discharge flow path. A fuel cell system comprising a radiator bypass channel for guiding a refrigerant flowing from the fuel cell side to the radiator side to the radiator through a path bypassing the ion exchanger.

  In the fuel cell system configured as described above, the refrigerant circulation path includes a path through the ion exchanger and a path through which the ion exchanger is bypassed. Therefore, if the refrigerant circulation path is switched according to the ion concentration in the refrigerant, the life of the ion exchanger can be extended. Moreover, when ion exchange is unnecessary, the pressure loss equivalent to an ion exchanger can be eliminated. Moreover, if it is set as the structure which switches the distribution route of a refrigerant | coolant according to the operating temperature of a fuel cell system, the ion removal in a refrigerant | coolant can be performed within the heat resistant range of an ion exchanger.

In addition to the configuration as the fuel cell system, the present invention can also be realized as a radiator of application example 14 and a refrigerant charging method of application example 15.
Application Example 14 A radiator for cooling a fuel cell with a liquid refrigerant, a core for exchanging heat with the refrigerant to cool the refrigerant, and a first tank disposed on both sides of the core And a second tank, wherein the first tank has an inlet for injecting the refrigerant into the radiator, and an opening connected to a supply flow path for introducing the refrigerant flowing through the core to the fuel cell. The second tank has a discharge opening that is connected to a discharge flow path that leads the refrigerant from the fuel cell to the radiator, and a path that bypasses the core. And an opening that is connected to the supply flow path through an ion exchanger that removes ions contained in the refrigerant, and is connected to a bypass flow path that leads the refrigerant flowing from the fuel cell side to the fuel cell again. Open for bypass It comprises a section, the supply opening and said outlet opening, in the direction of gravity, arranged radiator between the inlet and the bypass opening.

Application Example 15 In a fuel cell system including a fuel cell and a cooling system for cooling the fuel cell with a liquid refrigerant, a refrigerant charging method for charging the cooling system with the refrigerant, the cooling system Is between the fuel cell and the radiator including a core that performs heat exchange with the refrigerant and cools the refrigerant, an radiator that injects the refrigerant from outside the cooling system, and the fuel cell and the radiator. A refrigerant flow path for circulating the refrigerant; and an ion exchanger for removing ions contained in the refrigerant; injecting the refrigerant from the inlet; and at least part of the injected refrigerant in the core, A refrigerant filling method in which the cooling system is filled with the refrigerant after flowing in the order of the ion exchanger.

1 is a block diagram showing a configuration of a fuel cell system 20 as a first embodiment of the present invention. 4 is a perspective view for explaining the configuration of a radiator 50. FIG. 4 is an explanatory diagram showing a positional relationship in the gravity direction of devices constituting the fuel cell stack 30 and the cooling system device 40. FIG. 4 is an explanatory diagram showing a positional relationship of an ion exchanger 47 in a bypass channel 46. FIG. It is explanatory drawing which illustrates the opening-and-closing state of the initial state of the three-way valve. FIG. 3 is a cross-sectional view showing a part of the AA cross section of the radiator 50 shown in FIG. 2. It is explanatory drawing which shows the water level WL of the refrigerant | coolant at the time of filling with the refrigerant | coolant to the radiator 50. FIG. It is a block diagram which shows the structure of the fuel cell system 120 as 2nd Example of this invention. It is a perspective view for demonstrating the structure of the radiator 150 as 2nd Example. It is explanatory drawing which shows the positional relationship in the gravity direction of the apparatus which comprises the fuel cell stack 30 and the cooling system apparatus 40 as 2nd Example. It is a block diagram which shows the structure of the fuel cell system 220 as 3rd Example. It is a block diagram which shows the structure of the fuel cell system 320 as a 4th Example. It is explanatory drawing which shows the structure of the radiator 450 as a modification. It is sectional drawing which shows a part of BB cross section of the radiator 450 shown in FIG. It is explanatory drawing which shows the structure of the fuel cell cooling system as a prior art example.

A. First embodiment:
A-1. Schematic configuration of the fuel cell system 20:
FIG. 1 is a block diagram showing a configuration of a fuel cell system 20 as a first embodiment of the present invention. The fuel cell system 20 of this embodiment is mounted on a vehicle as a power source, and as shown in the figure, a fuel cell stack 30, a cooling system device 40, a fuel gas system device 70, and an oxidizing gas system device 80. And a control unit 90. However, the use of the fuel cell system 20 is not particularly limited, and the fuel cell system 20 may be mounted on various moving bodies or fixedly installed as a power source in a factory or a house.

  In this embodiment, the fuel cell stack 30 is a polymer electrolyte fuel cell, in which a plurality of single cells as power generators are stacked, and current collector plates (terminals) provided with output terminals on both sides in the stacking direction. ), An insulating plate (insulator), and an end plate are sequentially arranged. However, the type of the fuel cell is not limited to the solid polymer type, and various types such as a phosphoric acid type fuel cell can be used.

  The cooling system device 40 circulates the refrigerant with the fuel cell stack 30 and adjusts the operating temperature of the fuel cell stack 30. In this embodiment, water is used as the coolant, but the coolant may be liquid, for example, an antifreeze liquid to which ethylene glycol or the like is added. As shown in FIG. 1, the cooling system device 40 includes a radiator 50, a supply channel 41, a three-way valve 42, a refrigerant circulation pump 44, and a discharge channel 45. The radiator 50 exchanges heat between the refrigerant and the air to reduce the temperature of the refrigerant. The supply flow path 41 connects between the radiator 50 and the fuel cell stack 30, and a three-way valve 42 and a refrigerant circulation pump 44 are interposed therebetween. The discharge channel 45 connects between the fuel cell stack 30 and the radiator 50.

  When the refrigerant circulation pump 44 is driven, the refrigerant heat-exchanged by the radiator 50 flows through the supply passage 41 and is supplied to the fuel cell stack 30 via the three-way valve 42 and the refrigerant circulation pump 44. The refrigerant supplied to the fuel cell stack 30 flows through the refrigerant supply manifold 31, the refrigerant flow path 32, and the refrigerant discharge manifold 33 formed inside the fuel cell stack 30, and absorbs the heat of the fuel cell stack 30, It is discharged to the discharge channel 45.

  The cooling system device 40 includes a bypass channel 46 and an ion exchanger 47. The bypass channel 46 connects between the radiator 50 and the three-way valve 42, and an ion exchanger 47 is interposed therebetween. The radiator 50 and the bypass channel 46 are connected by a path that allows the refrigerant guided from the fuel cell stack 30 to the radiator 50 by the discharge channel 45 to be guided to the three-way valve 42 without performing heat exchange with the radiator 50. (Details will be described later). The ion exchanger 47 is provided to remove impurity ions eluted in the refrigerant from the radiator 50, the supply channel 41, the discharge channel 45, and the like, and suppress the conductivity of the refrigerant below a predetermined level.

  In such a cooling system device 40, the three-way valve 42 is normally controlled so that the refrigerant flows only through the supply flow path 41, or conversely, between the supply flow path 41 and the bypass flow path 46. Is done. The supply channel 41 and the bypass channel 46 are opened, and all or a part of the refrigerant circulating in the cooling system device 40 circulates through the ion exchanger 47 mainly in the fuel cell system 20. It is when power generation operation is started up or shut down. The reason for this control is that the ion exchanger 47 generally has low heat resistance, so that the refrigerant flows through the ion exchanger 47 only when the temperature of the fuel cell stack 30 is lower than a predetermined value. is there.

  However, if the ion exchanger 47 having high heat resistance can be used, the conductivity of the refrigerant detected by the conductivity meter provided in the path of the cooling system device 40 or the elapse of a predetermined period is determined in advance. The refrigerant may be circulated through the ion exchanger 47 when the threshold is exceeded. By configuring the refrigerant circulation path as described above, since the refrigerant does not flow through both the core 60 and the ion exchanger 47, pressure loss in the refrigerant flow can be suppressed. Moreover, since the refrigerant is allowed to flow through the ion exchanger 47 only for a limited period, the life of the ion exchanger 47 can be extended.

  The fuel gas system device 70 includes a hydrogen tank, a hydrogen shut-off valve, an injector, a hydrogen flow path, and the like (not shown), and supplies hydrogen as fuel gas stored in the hydrogen tank to the fuel cell stack 30. The exhaust gas subjected to the electrochemical reaction of the fuel cell stack 30 may be circulated and may be discharged out of the system continuously or intermittently. The oxidizing gas system device 80 includes a compressor, an air flow path, and the like (not shown), supplies air taken from the outside by the compressor to the fuel cell stack 30 as an oxidizing gas, and the electrochemical reaction of the fuel cell stack 30 And then discharged outside the system.

  Each component described above is controlled by the control unit 90. The control unit 90 is configured as a microcomputer including a CPU, a RAM, a ROM, and the like. The output request 91 and various types of fuel cell system 20 are developed by developing a program stored in the ROM and executing the program. In response to a signal from a sensor, for example, a temperature sensor or a voltage sensor, a drive signal is output to various actuators such as a hydrogen shut-off valve, an injector, a compressor, and a refrigerant circulation pump 44 to control the overall operation of the fuel cell system 20. .

A-2. Detailed configuration of the cooling system device 40:
A detailed configuration of the cooling system device 40 configuring the fuel cell system 20 described above will be described. FIG. 2 is a perspective view for explaining the configuration of the radiator 50. As shown in the drawing, the radiator 50 includes a core 60 and a first tank 51 and a second tank 52 disposed on both sides of the core 60 in a direction intersecting the direction of gravity.

  The first tank 51 includes an inlet 53 that is an opening for charging the cooling system device 40 with refrigerant from outside the system, and a supply opening 54 that is an opening for connecting to the supply flow path 41. I have. The injection port 53 of the present embodiment is provided so as to protrude from the end surface (upper surface) in the direction opposite to the gravitational direction (Z direction) of the first tank 51, and the through hole is formed along the Z direction inside the protruding portion. Is formed. Usually, the opening of the injection port 53 is sealed with a removable cap. The inlet 53 is provided at such a position in consideration of the convenience of the operation of injecting the refrigerant from the inlet 53, and the inlet 53 is not necessarily arranged on the upper surface of the first tank 51. It does not have to be. For example, the opening may be provided on the side surface of the first tank 51 at a higher position in the direction of gravity than the supply opening 54 so that the opening is in the Z direction. The inlet 53 may be provided at a position lower than the supply opening 54. In the supply opening 54 of this embodiment, the side surface of the first tank 51 protrudes in a cylindrical shape in the Y direction, and a through hole is formed in the inside along the Y direction. By fitting the cylindrical shape with the supply channel 41, the supply opening 54 and the supply channel 41 are connected.

  The second tank includes a discharge opening 55 for connecting to the discharge flow path 45 and a bypass opening 56 for connecting to the bypass flow path 46. In the discharge opening 55 and the bypass opening 56 of the present embodiment, the side surface of the second tank 52 protrudes in a cylindrical shape in the Y direction, and a through hole is formed in the inside along the Y direction. By fitting the cylindrical shape with the discharge flow path 45 and the bypass flow path 46, the discharge opening 55 and the discharge flow path 45, and the bypass opening 56 and the bypass flow path 46 are connected to each other. The bypass opening 56 is provided at a position lower than the discharge opening 55 in the direction of gravity. The supply opening 54 and the discharge opening 55 are provided between the inlet 53 and the bypass opening 56 in the gravity direction. That is, the bypass opening 56 is provided at a position lower than the supply opening 54 and the discharge opening 55 in the gravity direction.

  The core 60 is a part that performs heat exchange between the refrigerant and the air. Specifically, the core 60 includes a tube 61 and heat radiating fins 62. The tube 61 has a substantially rectangular cross-sectional shape along the direction (X direction) connecting the first tank 51 and the second tank 52, and a plurality of tubes 61 are provided along the direction of gravity. An end portion in the −X direction of each tube 61 is connected to the first tank 51, and an end portion in the X direction is connected to the second tank 52. Between the adjacent tubes 61, a heat dissipating fin 62 on a substantially wave is joined. A plurality of gaps 63 penetrating in the Y direction are formed between the tube 61 and the heat radiating fins 62.

  In the radiator 50 having such a configuration, the refrigerant that has absorbed heat by the fuel cell stack 30 and has flowed into the second tank 52 through the discharge flow path 45 and the discharge opening 55 flows through the tube 61 in the −X direction. . Here, in the gap 63, outside air, for example, vehicle speed wind of a vehicle on which the fuel cell system 20 is mounted or cooling air generated by driving a cooling fan flows in the Y direction. At this time, the refrigerant is cooled by exchanging heat with the outside air flowing through the gaps 63 via the tubes 61 and the radiation fins 62. The refrigerant thus cooled is guided to the first tank 51, flows into the fuel cell stack 30 through the supply opening 54 and the supply flow path 41, and again receives heat from the fuel cell stack 30. Absorb.

  FIG. 3 is an explanatory diagram showing the positional relationship in the gravity direction of the devices constituting the fuel cell stack 30 and the cooling system device 40. In FIG. 3, the refrigerant circulation pump 44 is not shown. In the cooling system device 40, the ion exchanger 47 is arranged at a position lower than the fuel cell stack 30 in the direction of gravity as shown in the drawing. Of the bypass channel 46, a path connecting the radiator 50 and the ion exchanger 47 is referred to as a bypass channel 46a, and a path connecting the ion exchanger 47 and the three-way valve 42 is referred to as a bypass channel 46b. Then, the bypass flow path 46a is arrange | positioned in the position lower than the fuel cell stack 30, and is further formed in the downward gradient. The bypass flow path 46a is disposed at a position lower than the discharge flow path 45 in the direction of gravity. In addition, the arrow in a figure has shown the flow of the refrigerant | coolant at the time of operation | movement of the cooling system apparatus 40. FIG.

  FIG. 4 is an explanatory diagram showing the positional relationship of the ion exchanger 47 in the bypass channel 46. As shown in the figure, on the path of the bypass channel 46, the ion exchanger 47 has a distance between the bypass opening 56 of the radiator 50 and the ion exchanger 47 (distance of the bypass channel 46 a). And the three-way valve 42 are disposed at positions that are shorter than the distance (distance of the bypass flow path 46b).

  FIG. 5 illustrates the open / closed state of the three-way valve 42 in the initial state. Here, the initial state refers to a state where the cooling system device 40 is not yet operated after the cooling system device 40 is assembled in the manufacturing stage. FIG. 5 shows an example in which a ball type is adopted as the three-way valve 42, but the type of the three-way valve 42 is not particularly limited, and for example, a diaphragm type or the like may be adopted. As shown in the drawing, in the initial state of the three-way valve 42, the open / close state of the bypass flow path 46 b communicating with the ion exchanger 47 and the supply flow path 41 on the side communicating with the radiator 50 is open. In the drawing, the open / closed state of the bypass flow path 46b and the supply flow path 41 communicating with the fuel cell stack 30 side is open, but the open / closed state may be either open / closed.

  FIG. 6 shows a part of the AA cross section of the radiator 50 shown in FIG. In the drawing, a state in which the refrigerant filling device 59 for filling the cooling system device 40 with the refrigerant is connected to the inlet 53 in the manufacturing / assembly stage of the cooling system device 40 is shown. As shown in the figure, a projection 57 that protrudes in the direction toward the inside of the first tank 51 along the side surface of the inlet 53 is formed inside the inlet 53. In the present embodiment, the protruding portion 57 is formed in a tapered shape so that the opening area inside the protruding portion 57 becomes smaller from the inlet 53 toward the first tank 51 (−Z direction). Yes. However, the protrusion 57 may not have such a tapered shape, and the refrigerant filling device 59 narrows the flow width of the refrigerant injected from the injection port 53 (the width in the direction intersecting the flow direction). What is necessary is just the shape which protruded. The taper shape is used to more effectively narrow the refrigerant flow width. In the drawing, a state in which the flow width of the refrigerant RE injected from the injection port 53 is narrowed by the protrusion 57 is shown. As shown in the figure, the protrusion 57 is not limited to the configuration provided in the opening on the −Z direction side of the injection port 53, and may be provided on the inner diameter of the injection port 53.

A-3. effect:
The effect of the fuel cell system 20 described above will be described. The effect of the present embodiment described below is an effect obtained when the refrigerant is charged into the cooling system device 40 in the manufacturing / assembly stage of the fuel cell system 20 due to the configuration of the fuel cell system 20 described above. . The refrigerant may be charged after the inside of the refrigerant path of the cooling system device 40 is depressurized, or the refrigerant may be pressurized and injected without depressurization. FIG. 7 shows the water level WL of the refrigerant in the radiator 50 when the refrigerant is injected from the inlet 53 of the radiator 50 and the cooling system device 40 is filled with the refrigerant. The X, Y, and Z directions in the figure correspond to the directions shown in FIG.

  When the injection of the refrigerant from the injection port 53 is started, the refrigerant starts to accumulate in the first tank 51. The injected refrigerant gradually flows through the tube 61 of the core 60 and starts to accumulate in the second tank 52. Here, the radiator 50 includes the supply opening 54 and the discharge opening 55 between the inlet 53 and the bypass opening 56 in the direction of gravity. In other words, the radiator 50 has a bypass opening. 56 is provided at a position lower than the supply opening 54 and the discharge opening 55, so that the refrigerant injected from the injection port 53 flows into the supply opening 54 and the discharge opening 55. However, it is easy to flow through the core 60 and flow into the bypass opening 56. For this reason, the water level WL at the time of refrigerant injection is higher on the water surface on the first tank 51 side than on the water surface on the second tank 52 side, as shown. Thus, since the refrigerant injected from the injection port 53 flows through the core 60 and then easily flows into the bypass opening 56, the refrigerant flowing through the core 60 passes through the bypass opening 56 and the bypass flow path 46. It becomes easy to distribute | circulate to the ion exchanger 47 via. Therefore, before starting the operation of the fuel cell system 20 for the first time (when charging the refrigerant), ions can be initially eluted from the core 60 into the refrigerant, and the eluted ions can be removed by the ion exchanger 47. . As a result, an increase in the conductivity of the refrigerant during the initial use of the fuel cell system 20 can be suppressed. In addition, since the increase in the conductivity of the refrigerant can be suppressed by the refrigerant filling process that is absolutely necessary in the manufacturing process of the fuel cell system 20, it is efficient. Of course, the lower the position of the bypass opening 56 in the direction of gravity, the better.

  In addition, as shown in FIG. 3, the fuel cell system 20 has a downward flow path 46 a between the bypass opening 56 and the ion exchanger 47, so that the refrigerant flowing through the core 60 is removed. It becomes easier to guide by the ion exchanger 47 through the bypass channel 46a. Further, since the ion exchanger 47 is arranged at a position lower than the fuel cell stack 30 in the direction of gravity, the injected refrigerant can be more easily guided to the ion exchanger 47 side than the fuel cell stack 30 side. As a result, the amount of refrigerant flowing through the core 60 and guided to the ion exchanger 47 can be increased.

  Further, as shown in FIG. 4, in the fuel cell system 20, on the path of the bypass flow path 46, the ion exchanger 47 has a distance between the bypass opening 56 of the radiator 50 and the ion exchanger 47. It is arranged at a position that is shorter than the distance between the exchanger 47 and the three-way valve 42. Therefore, it is possible to easily guide the refrigerant flowing through the core 60 by the ion exchanger 47.

  In the fuel cell system 20, as shown in FIG. 5, the three-way valve 42 includes, in an initial state, a bypass flow path 46 b that communicates with the ion exchanger 47 and a supply flow path 41 that communicates with the radiator 50. The open / close state of is open. If the refrigerant is injected from the injection port 53 in such a state, the supply channel 41 side is caused by the Bernoulli effect and the ejector effect as shown by the arrow direction in FIG. 6 except when the refrigerant is injected after the passage is evacuated. Since air is drawn in the -Z direction of the first tank 51 from the supply opening 54 through the supply opening 54, the injected refrigerant is less likely to flow from the supply opening 54 to the supply flow path 41 side. Therefore, the refrigerant can be easily guided by the ion exchanger 47. Moreover, since air is drawn from the supply flow path 41, the refrigerant guided to the ion exchanger 47 is easily guided to a path from the ion exchanger 47 to the radiator 50 side via the three-way valve 42. Therefore, the amount of the refrigerant flowing through the core 60 and guided to the ion exchanger 47 can be increased.

  Further, as shown in FIG. 6, the fuel cell system 20 includes a protrusion 57 that protrudes in the direction of narrowing the flow width of the refrigerant injected from the injection port 53 inside the injection port 53. Therefore, the flow width of the injected refrigerant can be narrowed, and the flow rate of the refrigerant flowing into the first tank 51 can be increased. As a result, the refrigerant can be more easily guided to the ion exchanger 47 by the Bernoulli effect and the ejector effect.

  Thus, at least a part of the refrigerant that is injected from the inlet 53 and filled in the cooling system device 40 through the radiator 50, the supply flow path 41, the discharge flow path 45, the ion exchanger 47, and the fuel cell stack 30 is provided. After the core 60 is circulated, the ion exchanger 47 is circulated and arranged in a positional relationship to be filled in the cooling system device 40, so that the operation of the fuel cell system 20 is started for the first time (charging of the refrigerant). Sometimes, ions can be initially eluted from the core 60 into the refrigerant and the eluted ions can be removed by the ion exchanger 47. As a result, an increase in the conductivity of the refrigerant during the initial use of the fuel cell system 20 can be suppressed. In the above-described embodiment, when the distance between the fuel cell stack 30 and the radiator 50 is short, for example, when the fuel cell stack 30 and the radiator 50 are mounted in an engine room (a space provided under the hood in front of the vehicle). Is particularly effective because the insulation resistance of the refrigerant may not be sufficiently secured.

  The amount of the refrigerant filled in the order of the core 60 and the ion exchanger 47 may be a part of the total amount of the refrigerant. However, in order to effectively suppress the increase in the conductivity of the refrigerant, the total amount It is desirable to set it as 20 to 30% or more. If the increase in the conductivity of the refrigerant during the initial operation of the fuel cell system 20 can be suppressed, then the ions eluting into the refrigerant perform an operation of circulating the refrigerant through the ion exchanger 47 when the fuel cell system 20 is started. As a result, it can be removed below a predetermined value.

B. Second Embodiment A fuel cell system 120 as a second embodiment of the present invention will be described. A schematic configuration of the fuel cell system 120 is shown in FIG. The fuel cell system 120 according to the second embodiment is different from the first embodiment in the configuration of the radiator and the connection relationship between the radiator, the discharge flow path, and the bypass flow path. In the following description, only differences from the first embodiment will be described, and the same components as those in the first embodiment will be denoted by the same reference numerals as those in the first embodiment, and description thereof will be omitted. As shown in FIG. 8, in the fuel cell system 120, the radiator 150 is connected to the supply channel 41 and the discharge channel 145, and has no connection relationship with the bypass channel 146. The bypass channel 146 branches in the middle of the discharge channel 145 and is connected to the three-way valve 42 via the ion exchanger 47.

  The structure of the radiator 150 is shown in FIG. As shown in the figure, the second tank 152 includes only the discharge opening 155 due to the connection relationship in the fuel cell system 120 described above. That is, the supply opening 54 shown in the first embodiment (FIG. 2) is not provided. Here, the discharge opening 155 is provided at a position lower in the gravity direction than the supply opening 54.

  FIG. 10 shows the positional relationship in the gravitational direction of the devices constituting the fuel cell stack 30 and the cooling system device 40 in the fuel cell system 120. Of the bypass channel 146, a path connecting the branch point with the discharge channel 145 and the ion exchanger 47 is a bypass channel 146a, and a path connecting the ion exchanger 47 and the three-way valve 42 is a bypass channel 146b. As shown in the figure, the bypass channel 146a is formed with a downward slope.

  In the fuel cell system 120 having such a configuration, since the discharge opening 155 is located in a position lower than the supply opening 54 in the direction of gravity, the refrigerant that has been injected from the injection port 53 and has started to accumulate in the first tank 51 is Rather than flowing into the supply opening 54, it becomes easier to flow through the core 60 and flow into the discharge opening 155. Here, although the discharge opening 155 communicates with the discharge flow path 145, the discharge flow path 145 branches off in the middle of the path to the fuel cell stack 30 and is connected to the bypass flow path 146. Therefore, the refrigerant injected and circulated through the core 60 can be easily guided to the ion exchanger 47, and before starting the operation of the fuel cell system 20 for the first time (at the time of charging the refrigerant), ions are introduced into the refrigerant from the core 60. Initial elution is performed, and the eluted ions can be removed by the ion exchanger 47. As a result, an increase in the conductivity of the refrigerant during the initial use of the fuel cell system 20 can be suppressed.

  Further, since the bypass flow path 146a branched from the discharge flow path 145 is formed with a downward slope, the refrigerant that has been injected from the injection port 53, flows through the core 60, and flows into the discharge opening 155 is supplied to the fuel cell. It becomes easier to guide to the ion exchanger 47 than the stack 30. Although description is omitted, it is needless to say that the same configuration as that of the first embodiment has the same effect as that of the first embodiment.

C. Third embodiment:
A fuel cell system 220 as a third embodiment of the present invention will be described. A schematic configuration of the fuel cell system 220 is shown in FIG. The fuel cell system 220 according to the third embodiment is different from the first embodiment in the connection relationship between the radiator, the discharge passage, and the bypass passage. In the following description, only differences from the first embodiment will be described, and the same components as those in the first embodiment will be denoted by the same reference numerals as those in the first embodiment, and description thereof will be omitted. As shown in FIG. 11, in the fuel cell system 220, the discharge flow path 245 connected to the fuel cell stack 30 is branched into a discharge flow path 245a and a discharge flow path 245b via a three-way valve 248. . The discharge flow path 245a includes an ion exchanger 247 on the path, and is connected to the bypass opening 56 (see FIG. 2) of the radiator 50. The discharge flow path 245b is connected to the discharge opening 55 (see FIG. 2) of the radiator 50.

  The fuel cell system 220 normally circulates the refrigerant through the discharge flow path 245b that bypasses the ion exchanger 247. However, when the fuel cell system 220 is started up, the discharge flow through the ion exchanger 247 is not limited. The refrigerant is circulated through the path 245a. The discharge channel 245b is not essential, and may be omitted when the heat resistance of the ion exchanger 247 can be ensured or when the pressure loss can be suppressed.

  Although illustration is omitted, the discharge flow path 245 a between the radiator 50 and the ion exchanger 247 and the ion exchanger 247 are disposed at a position lower than the fuel cell stack 30 in the gravity direction. Further, the discharge flow path 245a between the radiator 50 and the ion exchanger 247 is formed with a downward slope. As in the first embodiment, the fuel cell system 220 having such a configuration is easy to guide the refrigerant that has been injected and circulated through the core 60 to the bypass opening 56. Also, the above-described discharge flow path 245a, ion exchanger 247, The refrigerant is easily guided to the ion exchanger 247 depending on the positional relationship of the fuel cell stack 30 and the like. Therefore, an increase in the conductivity of the refrigerant during the initial use of the fuel cell system 220 can be suppressed.

D. Fourth embodiment:
A fuel cell system 320 as a fourth embodiment of the present invention will be described. A schematic configuration of the fuel cell system 320 is shown in FIG. The fuel cell system 320 according to the fourth embodiment is different from the second embodiment in the connection relationship between the radiator, the discharge passage, and the bypass passage. In the following description, only differences from the second embodiment will be described, and the same configurations as those of the second embodiment will be denoted by the same reference numerals as those of the second embodiment, and description thereof will be omitted. As shown in FIG. 12, in the fuel cell system 320, the discharge channel 345 connected to the fuel cell stack 30 is branched into a discharge channel 345a and a discharge channel 345b via a three-way valve 348. . The discharge flow path 345b is connected to the discharge opening 155 (see FIG. 9) of the radiator 150 via the three-way valve 349. The discharge channel 345 a includes an ion exchanger 347 on the path, and is connected to the three-way valve 349.

  The fuel cell system 320 normally circulates the refrigerant through the discharge flow path 345b bypassing the ion exchanger 347. However, when the fuel cell system 220 is started up, the discharge flow through the ion exchanger 347 is not limited. The refrigerant is circulated through the path 345a. The discharge channel 345b is not essential, and may be omitted when the heat resistance of the ion exchanger 347 can be ensured or when the pressure loss can be suppressed.

  Although illustration is omitted, the discharge flow path 345a between the three-way valve 349 and the ion exchanger 347 and the ion exchanger 347 are disposed at a position lower than the fuel cell stack 30 in the gravity direction. Further, the discharge flow path 345a between the radiator 150 and the ion exchanger 347 is formed with a downward slope. As in the second embodiment, the fuel cell system 320 having such a configuration is easy to guide the refrigerant that has been injected and circulated through the core 60 to the discharge opening 155. Further, the discharge channel 345a, the ion exchanger 347, The refrigerant is easily guided to the ion exchanger 347 depending on the positional relationship of the fuel cell stack 30 and the like. Therefore, an increase in the conductivity of the refrigerant during the initial use of the fuel cell system 320 can be suppressed.

E. Variations:
A modification of the above embodiment will be described.
E-1. Modification 1:
In the above-described embodiment, the radiator 50 constituting the fuel cell system 20 has been described with respect to a so-called side flow type configuration in which the refrigerant flows in a direction intersecting the direction of gravity. However, the configuration is not limited to such a configuration. For example, the radiator may be a so-called down flow system in which the refrigerant flows in the direction of gravity.

  A specific example of a radiator as a downflow system is shown in FIG. 13 as a radiator 450. As illustrated, the radiator 450 includes a core 460 and a first tank 451 and a second tank 452 arranged on both sides of the core 460 in the direction of gravity. The first tank 451 has an inlet 453 on its upper surface and a supply opening 454 on its side surface. The second tank 452 includes a discharge opening 455 and a bypass opening 456 on its side surface. The core 460 includes a plurality of tubes 461 connecting the first tank 451 and the second tank 452 and heat radiating fins 462 disposed between the adjacent tubes 461.

  Since these configurations are the same as those in the first embodiment, detailed description thereof is omitted, but the positional relationship among the inlet 453, the supply opening 454, the discharge opening 455, and the bypass opening 456 is the same as that of the first embodiment. This is the same as in the first embodiment. With such a configuration, the same effect as that of the first embodiment can be obtained not only in the flow direction of the refrigerant in the radiator. Of course, in the second to fourth embodiments as well, it is possible to adopt the down flow method.

  FIG. 14 shows a BB cross section of the radiator 450 shown in FIG. As described above, also in the downflow type radiator 450, if the protrusion 457 is provided inside the injection port 453, the flow width of the injected refrigerant is narrowed and flows into the core 460 as in the above-described embodiment. The flow rate of the refrigerant can be increased, and the refrigerant can be more easily guided to the ion exchanger 47.

E-2. Modification 2:
In addition to the configuration of the first embodiment, the non-electrically operating structure prevents the refrigerant from flowing from the radiator 50 side to the fuel cell stack 30 side or discharges the means for blocking the refrigerant circulation itself. It may be provided on the path 45. As such means, for example, a check valve or a pinch can be used. If a check valve is interposed in the discharge flow path 45 in a direction in which the refrigerant does not flow from the radiator 50 side to the fuel cell stack 30 side, the refrigerant injected from the inlet 53 is discharged from the discharge flow path 145 to the fuel cell stack 30. Therefore, after flowing through the core 60, the amount of the refrigerant filled in the cooling system device 40 can be increased by flowing through the ion exchanger 47.

  Further, if a pinch is interposed in the discharge channel 45 and the pinch is closed during the refrigerant filling operation, the same effect can be obtained. The structure that operates non-electrically is used to fill the cooling system device 40 with the refrigerant before assembling the fuel cell system 20 and starting the operation for the first time. In addition to the configuration of the second embodiment, when a check valve or the like is interposed in the discharge channel 145 between the branch point of the discharge channel 145 and the bypass channel 146 and the fuel cell stack 30, In addition to the configuration of the embodiment, when a check valve or the like is interposed in the discharge flow path 245b, in addition to the configuration of the fourth embodiment, the discharge flow path 345b between the three-way valve 348 and the three-way valve 349 is reversed. The same effect can be obtained when a stop valve or the like is interposed.

  As mentioned above, although embodiment of this invention was described, elements other than the element described in the independent claim among the components of this invention in embodiment mentioned above are additional elements, and are suitably abbreviate | omitted or combined. Is possible. Moreover, although the embodiment of the present invention has been described, the present invention is not limited to such an example, and it is needless to say that the present invention can be implemented in various modes without departing from the gist of the present invention. For example, the present invention can be realized as a radiator and refrigerant injection method in addition to the configuration as a fuel cell system.

20, 120, 220, 320 ... Fuel cell system 30 ... Fuel cell stack 31 ... Refrigerant supply manifold 32 ... Refrigerant flow path 33 ... Refrigerant discharge manifold 40 ... Cooling system equipment 41 ... Supply flow path 42, 248, 348, 349 ... Three-way Valve 44 ... Refrigerant circulation pump 45, 145, 245, 245a, 245b, 345, 345a, 345b ... Discharge flow path 46, 46a, 46b, 146, 146a, 146b ... Bypass flow path 47, 247, 347 ... Ion exchanger 50 , 150, 450 ... Radiators 51, 451 ... First tank 52, 152, 452 ... Second tank 53, 453 ... Inlet 54, 454 ... Supply opening 55, 155, 455 ... Discharge opening 56, 456 ... Bypass opening 57, 457 ... Projection 59 ... Refrigerant filling device 60, 460 ... Core 61,461 ... tube 62,462 ... radiation fin 63 ... gap 70 ... fuel gas equipment 80 ... oxidation gas equipment 90 ... control unit 91 ... output request RE ... refrigerant WL ... water surface level S1, S2 ... section

Claims (14)

A fuel cell system comprising a fuel cell and a cooling system for cooling the fuel cell with a liquid refrigerant,
The cooling system is
A radiator including a core that performs heat exchange with the refrigerant to cool the refrigerant, and an inlet for injecting the refrigerant from outside the cooling system;
A supply flow path for guiding the refrigerant flowing through the core from the radiator to the fuel cell;
A discharge passage for guiding the refrigerant from the fuel cell to the radiator;
An ion exchanger provided on a flow path of the refrigerant and removing ions contained in the refrigerant;
At least a part of the refrigerant that is injected from the inlet and filled in the cooling system into the radiator, the supply channel, the discharge channel, the ion exchanger, and the fuel cell is the core, the ion exchange The fuel cell system is arranged in a positional relationship in which the cooling system is filled after being distributed in the order of the vessels.   2. The fuel cell system according to claim 1, wherein at least one of paths from the radiator to the ion exchanger and the ion exchanger are disposed at a lower position in the gravity direction than the fuel cell.   The fuel cell system according to claim 1 or 2, wherein at least one of paths from the radiator to the ion exchanger is formed with a downward slope. A fuel cell system according to any one of claims 1 to 3,
Furthermore, a core bypass flow path that is connected to the supply flow path and guides the refrigerant flowing from the fuel cell side to the radiator side to the supply flow path through a path that bypasses the core,
The ion exchanger is a fuel cell system provided on the core bypass channel.   Of the core bypass channel, a path from the end opposite to the connection point between the core bypass channel and the supply channel to the ion exchanger, and the ion exchanger are the fuel cell The fuel cell system according to claim 4, wherein the fuel cell system is disposed at a lower position in the direction of gravity.   5. The core bypass channel according to claim 4, wherein a path from the end opposite to the connection point between the core bypass channel and the supply channel to the ion exchanger is formed with a downward slope. 5. The fuel cell system according to 5. The fuel cell system according to any one of claims 4 to 6,
The radiator includes a first tank and a second tank disposed on both sides of the core,
The first tank includes the inlet and a supply opening that is an opening connected to the supply flow path.
The second tank includes a discharge opening which is an opening connected to the discharge flow path, and a bypass opening which is an opening connected to the core bypass flow path.
The fuel cell system, wherein the supply opening and the discharge opening are arranged between the inlet and the bypass opening in a direction of gravity. The fuel cell system according to any one of claims 4 to 6,
The radiator includes a first tank and a second tank disposed on both sides of the core,
The first tank includes the inlet and a supply opening that is an opening connected to the supply flow path.
The second tank includes a discharge opening which is an opening connected to the discharge flow path,
The discharge opening is provided at a lower position in the direction of gravity than the supply opening,
The fuel cell system, wherein the core bypass channel has an end opposite to a connection point between the core bypass channel and the supply channel connected to the discharge channel. The fuel cell system according to claim 7 or 8, wherein
And a three-way valve that is provided at a connection point between the supply flow path and the core bypass flow path and adjusts the flow rate of the refrigerant flowing through the core and the ion exchanger,
The three-way valve enables communication between the core bypass passage and the passage on the radiator side of the three-way valve in the supply passage.   10. The fuel cell system according to claim 9, wherein the injection port includes a protrusion protruding in a direction of narrowing a flow width in a direction intersecting a flow direction of the refrigerant injected from the injection port inside the injection port. A fuel cell system according to any one of claims 4 to 10, wherein
The discharge channel has a structure that operates non-electrically between the end of the core bypass channel opposite to the connection point between the core bypass channel and the supply channel, and the fuel cell. A fuel cell system comprising a backflow prevention unit that prevents the refrigerant from flowing in the direction from the radiator side toward the fuel cell side or blocks the refrigerant flow.   The ion exchanger has a path on the path from the end opposite to the connection point between the core bypass channel and the supply channel to the ion exchanger, and the path from the connection point to the ion exchanger. 12. The fuel cell system according to claim 4, wherein the fuel cell system is provided at a position that is shorter than the upper distance. A fuel cell system according to any one of claims 1 to 3,
The ion exchanger is provided on the discharge channel,
The fuel cell further includes an ion exchange bypass channel connected in parallel to the discharge channel and guiding the refrigerant flowing from the fuel cell side to the radiator side to the radiator through a path bypassing the ion exchanger. system. In a fuel cell system comprising a fuel cell and a cooling system for cooling the fuel cell with a liquid refrigerant, a refrigerant filling method for filling the cooling system with the refrigerant,
The cooling system is
A radiator including a core that performs heat exchange with the refrigerant to cool the refrigerant, and an inlet that injects the refrigerant from outside the cooling system;
A refrigerant flow path for circulating the refrigerant between the fuel cell and the radiator;
An ion exchanger for removing ions contained in the refrigerant,
Injecting the refrigerant from the inlet,
A refrigerant filling method in which at least a part of the injected refrigerant is circulated in the order of the core and the ion exchanger, and then the cooling system is filled with the refrigerant.

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