fuel cells

Abstract

This technology provides an improved heat dissipation performance for the cover that surrounds the cell monitor. [Solution] The fuel cell comprises a fuel cell stack in which a plurality of fuel cell cells are stacked, a cell monitor disposed on the fuel cell stack and detecting at least one of the voltage and current of the fuel cell stack, a cover portion that covers at least one surface of the cell monitor, and a case that integrally houses the fuel cell stack, the cell monitor, and the cover portion. The cover portion has a first surface facing the cell monitor and a second surface connected to the first surface and in surface contact with the inside of the case.

Description

Technical Field

[0001] The present disclosure relates to a fuel cell.

Background Art

[0002] There is known a fuel cell in which a fuel cell stack and a cell monitor for detecting the voltage of the fuel cell stack are housed in a case. The fuel cell described in Patent Document 1 is covered with a cover that shields electromagnetic noise by the cell monitor.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There has been a problem of improving the heat dissipation performance of the cover that covers the cell monitor.

Means for Solving the Problems

[0005] The present disclosure has been made to solve the above problems and can be realized in the following forms.

[0006] According to an aspect of the present disclosure, a fuel cell is provided. The fuel cell includes a fuel cell stack in which a plurality of fuel cells are stacked, a cell monitor disposed on the fuel cell stack and detecting at least one of the voltage and current of the fuel cell stack, a cover portion covering at least one surface of the cell monitor, and a case integrally housing the fuel cell stack, the cell monitor, and the cover portion. The cover portion has a first surface facing the cell monitor and a second surface connected to the first surface and in surface contact with the inside of the case. With this type of fuel cell, heat can be dissipated from the cover to the case via the second surface. Therefore, the amount of heat dissipated from the cover can be increased.

[0007] Furthermore, this disclosure can be implemented in various forms, for example, in the form of a vehicle equipped with this fuel cell or a method for manufacturing the fuel cell. [Brief explanation of the drawing]

[0008] [Figure 1] This is an explanatory diagram of a fuel cell. [Figure 2] This is a cross-sectional view obtained by cutting along the line II-II in Figure 1. [Figure 3] This is a perspective view of the cover. [Modes for carrying out the invention]

[0009] A. First Embodiment: Figure 1 is an explanatory diagram of a fuel cell 100 in one embodiment of the present disclosure. Figure 2 is a cross-sectional view obtained by cutting Figure 1 along the line II-II. In this embodiment, the fuel cell 100 is mounted as a power source for a vehicle driven by a drive motor. The fuel cell 100 comprises a fuel cell stack 10, a cell monitor 20, a cover portion 30, a converter 40, and a case 60. Figure 1 shows the x, y, and z axes which are orthogonal to each other. The y axis is the stacking direction of the fuel cell cells 11, which will be described later. The x axis is the direction orthogonal to the y axis. The z axis is the direction orthogonal to the x and y axes and is the vertical direction. These axes correspond to the axes shown in Figures 1 and later.

[0010] The fuel cell stack 10 is a solid polymer fuel cell that generates electricity through an electrochemical reaction between hydrogen and oxygen. The fuel cell stack 10 is composed of multiple fuel cell cells 11 stacked on top of each other. The fuel cell stack 10 includes terminal plates, end plates, housings, etc., which are not shown. Each fuel cell 11 is a power generation element that can generate electricity on its own, and has a membrane electrode gas diffusion layer assembly in which gas diffusion layers are arranged on both sides of a membrane electrode assembly having an electrolyte membrane, and separators arranged on both outer sides of the membrane electrode gas diffusion layer assembly. The electrolyte membrane is composed of a solid polymer thin film that exhibits good proton conductivity when in a wet state containing moisture inside.

[0011] The cell monitor 20 is a monitor for detecting the power generation status of the fuel cell stack 10. In this embodiment, the cell monitor 20 detects the output voltage of each fuel cell cell 11. The detection results from the cell monitor 20 are output to a control unit (not shown) that controls the operation of the fuel cell stack 10. The cell monitor 20 is also located on the fuel cell stack 10. The cell monitor 20 is electrically connected to the fuel cell stack 10 via a cable (not shown).

[0012] The cover portion 30 is a metal component that covers one side of the cell monitor 20. In this embodiment, the cover portion 30 covers the upper surface of the cell monitor 20. The cover portion 30 is a component that protects the cell monitor 20 from radiant heat from other components such as the converter 40. In this embodiment, the cover portion 30 is made of aluminum. The cover portion 30 is fixed to the case 60 by fastening members 50.

[0013] The converter 40 is a device that performs a voltage boosting operation to raise the output voltage of the fuel cell stack 10 to a target voltage. In this embodiment, the converter 40 is positioned vertically above the fuel cell stack 10 (in the +z axis direction). More specifically, the converter 40 is positioned near the vertically above the cover portion 30 (in the +z axis direction) and is heated by radiant heat.

[0014] The case 60 integrally houses the fuel cell stack 10, the cell monitor 20, the cover portion 30, and the converter 40. The case 60 is made of, for example, aluminum. In this embodiment, the case 60 is fixed to the vehicle.

[0015] Figure 3 is a perspective view of the cover portion 30. The cover portion 30 has a first surface 31, a second surface 32, a third surface 33, and a fourth surface 34.

[0016] The first surface 31 is the surface facing the cell monitor 20. The second surface 32, the third surface 33, and the fourth surface 34 are all connected to the first surface 31, extend downward (in the -z-axis direction) from the first surface 31, and are surfaces that make surface contact with the inside of the case 60. In this embodiment, the first surface 31 has a substantially rectangular shape with a first side 31a, a second side 31b, a third side 31c, and a fourth side 31d. The second surface 32 is the surface connected to the second side 31b of the first surface 31. The third surface 33 is the surface connected to the third side 31c of the first surface 31. The fourth surface 34 is the surface connected to the fourth side 31d of the first surface 31.

[0017] Furthermore, in this embodiment, the second surface 32, the third surface 33, and the fourth surface 34 have protective members on the surfaces that come into contact with the inside of the case 60. The protective members suppress corrosion of the cover portion 30 and wear of the cover portion 30 caused by vibrations resulting from the movement of the vehicle on which the fuel cell 100 is installed. More specifically, a resin sheet such as silicone or ceramic is attached to the surfaces of the second surface 32, the third surface 33, and the fourth surface 34 that come into contact with the case 60. This prevents a reduction in the contact area between the cover portion 30 and the case 60.

[0018] As described above, the fuel cell 100 of this embodiment allows heat to be dissipated from the cover portion 30 to the case 60 via the second surface 32, the third surface 33, and the fourth surface 34. Therefore, the contact area between the cover portion 30 and the case 60 is increased compared to when only the fastening member 50 is in contact with the case 60. Consequently, the amount of heat dissipated from the cover portion 30 can be increased.

[0019] B. Other Embodiments: (B1) In the above-described embodiment, the cell monitor 20 detects the output voltage of each fuel cell 11. However, this is not the only case, and the cell monitor 20 may detect the overall voltage of the fuel cells 11. Further, the cell monitor 20 may detect at least one of the voltage and current of the fuel cell stack 10.

[0020] (B2) In the above-described embodiment, the cover portion 30 covers the upper surface of the cell monitor 20. However, this is not the only case, and the cover portion 30 may cover at least one surface so as to protect from the radiant heat of other members, and may cover the side surface of the cell monitor 20. Further, the cover portion 30 may accommodate the connector for connecting the cell monitor 20 to the fuel cell stack 10 in a state where it is exposed to the outside.

[0021] (B3) In the above-described embodiment, the cover portion 30 has the second surface 32, the third surface 33, and the fourth surface 34. However, this is not the only case, and the cover portion 30 may have only one surface that is connected to the first surface 31 and is in surface contact with the inside of the case 60.

[0022] (B4) In the above-described embodiment, the second surface 32, the third surface 33, and the fourth surface 34 all extend downward (-z-axis direction) from the first surface 31. However, this is not the only case, and the second surface 32, the third surface 33, and the fourth surface 34 may extend in an arbitrary direction from the first surface 31.

[0023] (B5) In the above-described embodiment, the second surface 32, the third surface 33, and the fourth surface 34 have a protective member on the surface on the side that contacts the case 60. However, this is not the only case, and the second surface 32, the third surface 33, and the fourth surface 34 may not have a protective member on the surface on the side that contacts the inside of the case 60.

[0024] This disclosure is not limited to the embodiments described above, and can be implemented in various configurations without departing from its spirit. For example, the technical features in the embodiments corresponding to the technical features in each form described in the summary of the invention can be replaced or combined as appropriate in order to solve the problems described above or to achieve some or all of the effects described above. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate. [Explanation of symbols]

[0025] 10…Fuel cell stack, 11…Fuel cell cell, 20…Cell monitor, 30…Cover section, 31…First surface, 31a…First edge, 31b…Second edge, 31c…Third edge, 31d…Fourth edge, 32…Second surface, 33…Third surface, 34…Fourth surface, 40…Converter, 50…Fastening member, 60…Case, 100…Fuel cell

Claims

[Claim 1] It is a fuel cell, A fuel cell stack consisting of multiple fuel cell cells stacked on top of each other, A cell monitor is placed on the fuel cell stack and detects at least one of the voltage and current of the fuel cell stack. The cover portion that covers the cell monitor, The system comprises a case that integrally houses the fuel cell stack, the cell monitor, and the cover portion, The cover portion has a first surface facing the cell monitor and a second surface connected to the first surface and in surface contact with the inside of the case, wherein the fuel cell.

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