Solid oxide fuel cells

Abstract

To provide a solid oxide fuel cell capable of increasing the heating efficiency and raising the temperature of an inner structure to a target temperature (an operation temperature) in a short time and with low energy.SOLUTION: A solid oxide fuel cell 100 comprises: an electrolyte ceramic 3; an electrode part 1 that comprises an anode electrode 4 and a cathode electrode 5 sandwiching the electrolyte ceramic 3 from both sides; a metal frame 2 arranged around the electrode part 1 so as to sandwich the electrode part 1 from both sides, being physically in contact with the anode electrode 4 and the cathode electrode 5, respectively; and a power feeding port 7 electrically connected with the metal frame 2 to feed high-frequency power to the metal frame 2. The thickness of the electrode part 1 becomes thinner in a predetermined concentration heating region.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a solid oxide fuel cell. [Background technology]

[0002] A solid oxide fuel cell (SOFC) is a fuel cell in which a cell is constructed by sandwiching an electrolyte ceramic between an anode layer and a cathode layer. SOFCs have a high operating temperature, and the internal structure (cell, etc.) must be heated to nearly 700 degrees to start generating electricity.

[0003] A conventional method for heating SOFCs is to heat the external structure (such as the housing) using a gas burner. However, this method using a gas burner has the problem that the internal structure is indirectly heated using heat applied to the external structure, resulting in low heating efficiency and requiring a long time and a large amount of energy for the internal structure to reach the target temperature (operating temperature). Another problem with the method using a gas burner is that it generates emissions such as NOx (nitrogen oxides).

[0004] Therefore, a method of heating the power generating body (cell) of an SOFC by irradiating it with microwaves has been proposed (see, for example, Patent Document 1). This heating method using microwaves suppresses the generation of emissions such as NOx (nitrogen oxides). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-165516 Summary of the Invention [Problem to be solved by the invention]

[0006] However, conventional heating methods using microwaves do not provide sufficiently high heating efficiency, and there is still the problem that it takes a long time and a large amount of energy for the internal structure to reach the target temperature (operating temperature).

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a solid oxide fuel cell that has high heating efficiency and can raise the temperature of the internal structure to a target temperature (operating temperature) in a short time with little energy. [Means for solving the problem]

[0008] The solid oxide fuel cell of the present invention comprises an electrode section including an electrolyte ceramic and an anode electrode and a cathode electrode sandwiching the electrolyte ceramic from both sides, a metal frame arranged around the electrode section so as to sandwich the electrode section from both sides and being in physical contact with the anode electrode and the cathode electrode, and a power supply port electrically connected to the metal frame for supplying high-frequency power to the metal frame, and the thickness of the electrode section is configured to be thinner in a predetermined concentrated heating region.

[0009] With this configuration, when power is supplied from the power supply port to the metal frame arranged around the electrode unit, high frequency waves are supplied directly to the electrode unit through the metal frame, and the electrode unit is heated by the supplied high frequency waves. In this case, the internal structure (electrode unit) is directly heated using the high frequency waves applied to the internal structure, so the temperature of the internal structure can be raised to the target temperature (operating temperature) with high heating efficiency and in a short time with little energy.

[0010] Furthermore, since the thickness of the electrode portion is configured to be thin in a predetermined concentrated heating region, an electric field can be concentrated in the thinned region (concentrated heating region), allowing for concentrated heating. For example, by thinning the thickness of the center of the electrode portion (providing a concentrated heating region in the center of the electrode portion), it is possible to concentrate heating in the center of the electrode portion and raise the temperature to a high level. Furthermore, by thinning the thickness of the outer portion of the electrode portion (providing a concentrated heating region in the outer portion of the electrode portion), it is possible to concentrate heating in the outer portion of the electrode portion and raise the temperature to a high level. The thickness of the electrode portion can be adjusted by changing the thickness of one or more of the materials of the electrolyte ceramic, the anode electrode, and the cathode electrode.

[0011] In the solid oxide fuel cell of the present invention, the predetermined concentrated heating region may be a region of the electrode portion that is preset as a region where heating efficiency is low.

[0012] With this configuration, if there are areas where the heating effect is high due to conditions such as the mechanical structure of the electrode and metal frame and the frequency of the high-frequency power supply, the electrode can be heated uniformly by reducing the thickness of the areas where the heating effect is low. The concentrated heating areas can be set in advance based on the measurement results of a prior measurement of the heating efficiency of the electrode.

[0013] In addition, in the solid oxide fuel cell of the present invention, the anode electrode and the cathode electrode may have a mesh structure, and the mesh density of the mesh structure in the predetermined concentrated heating region may be configured to be higher than the mesh density of the mesh structure in regions other than the concentrated heating region.

[0014] According to this configuration, the mesh density of the mesh structure of the anode electrode and the cathode electrode is increased in a predetermined concentrated heating region, so that an electric field can be concentrated in the region with the increased mesh density (concentrated heating region), enabling concentrated heating. For example, by increasing the mesh density in the center of the electrode portion (providing a concentrated heating region in the center of the electrode portion), it is possible to heat the center of the electrode portion in a concentrated manner and raise the temperature. Furthermore, by increasing the mesh density in the outer portion of the electrode portion (providing a concentrated heating region in the outer portion of the electrode portion), it is possible to heat the outer portion of the electrode portion in a concentrated manner and raise the temperature.

[0015] Furthermore, for example, if there are areas where the heating effect is high due to conditions such as the mechanical structure of the electrode portion and metal frame and the frequency of the high-frequency power being supplied, the electrode portion can be heated uniformly by increasing the mesh density in the areas where the heating effect is low.

[0016] In the solid oxide fuel cell of the present invention, the high-frequency oscillator that generates the high-frequency wave may include a power control unit that controls the high-frequency power supplied to the power supply port in accordance with the temperature of the electrode unit.

[0017] With this configuration, the high-frequency power supplied to the power supply port is controlled according to the temperature of the electrode unit. When the temperature of the electrode unit increases, less high-frequency power needs to be supplied to the power supply port (compared to when the temperature of the electrode unit is low). Therefore, by reducing the high-frequency power supplied to the power supply port as the temperature of the electrode unit increases, the total amount of high-frequency power supplied can be reduced.

[0018] The solid oxide fuel cell of the present invention may also include a pulse drive control section that pulse-drives the high-frequency oscillator that generates the high-frequency wave on a time axis.

[0019] According to this configuration, the high-frequency oscillator is controlled to be pulse-driven on the time axis (pulse drive control). Even if the high-frequency oscillator is pulse-driven (for example, on-off control), the temperature of the electrode portion can be sufficiently increased by setting the duty ratio of the on-off control so that the temperature increase during the on-time exceeds the temperature decrease during the off-time. When the high-frequency oscillator is on-controlled, high-frequency power is supplied to the power supply port, but when the high-frequency oscillator is off-controlled, high-frequency power is not supplied to the power supply port. Therefore, the total amount of high-frequency power supplied can be reduced. Furthermore, even if the heated cells are unevenly positioned, the cell temperature is dispersed during the off-time, making the cell temperature uniform. Furthermore, by reducing the continuous operation time of the high-frequency oscillator, the life of the high-frequency oscillator can be extended.

[0020] The solid oxide fuel cell of the present invention may also include a switch circuit that switches the destination of the high-frequency power supplied from the high-frequency oscillator to the power supply port to the power supply port of another solid oxide fuel cell, and a switch drive control unit that switches the switch circuit.

[0021] According to this configuration, the switch drive control unit controls the switch circuit to switch the destination of the high-frequency power supplied from the high-frequency oscillator to the power supply port to the power supply port of another solid oxide fuel cell. This makes it possible to continuously supply high-frequency power from one high-frequency oscillator to the power supply ports of multiple solid oxide fuel cells over time. For example, the duty ratio of the switch drive control may be varied according to the temperature difference between the electrodes of each solid oxide fuel cell. It may also be varied according to the ratio of the physical sizes of each solid oxide fuel cell.

[0022] The solid oxide fuel cell of the present invention comprises an electrode section including an electrolyte ceramic and an anode electrode and a cathode electrode sandwiching the electrolyte ceramic from both sides, a metal frame arranged around the electrode section so as to sandwich the electrode section from both sides and being in physical contact with the anode electrode and the cathode electrode, and a power supply port electrically connected to the metal frame for supplying high-frequency power to the metal frame, wherein the anode electrode and the cathode electrode have a mesh structure, and the mesh density of the mesh structure in a specified concentrated heating region is configured to be higher than the mesh density of the mesh structure in regions other than the concentrated heating region.

[0023] With this configuration, when power is supplied from the power supply port to the metal frame arranged around the electrode unit, high frequency waves are supplied directly to the electrode unit through the metal frame, and the electrode unit is heated by the supplied high frequency waves. In this case, the internal structure (electrode unit) is directly heated using the high frequency waves applied to the internal structure, so the temperature of the internal structure can be raised to the target temperature (operating temperature) with high heating efficiency and in a short time with little energy.

[0024] Furthermore, since the mesh density of the mesh structure of the anode electrode and cathode electrode is configured to be high in a predetermined concentrated heating region, an electric field is concentrated in the region with high mesh density (concentrated heating region), allowing for concentrated heating. For example, by increasing the mesh density in the center of the electrode portion (providing a concentrated heating region in the center of the electrode portion), it is possible to concentrate heating in the center of the electrode portion and raise the temperature. Also, by increasing the mesh density in the outer portion of the electrode portion (providing a concentrated heating region in the outer portion of the electrode portion), it is possible to concentrate heating in the outer portion of the electrode portion and raise the temperature.

[0025] In the solid oxide fuel cell of the present invention, the predetermined concentrated heating region may be a region of the electrode portion that is preset as a region where heating efficiency is low.

[0026] With this configuration, if there are areas where the heating effect is high due to conditions such as the mechanical structure of the electrode and metal frame and the frequency of the high-frequency power supplied, the electrode can be heated uniformly by increasing the mesh density of the areas where the heating effect is low. The concentrated heating areas can be set in advance based on the measurement results of a prior measurement of the heating efficiency of the electrode. [Effects of the Invention]

[0027] According to the present invention, the temperature of the internal structure can be raised to a target temperature (operating temperature) with high heating efficiency, in a short time, and with little energy. [Brief explanation of the drawings]

[0028] [Figure 1] FIG. 1 is an explanatory diagram showing the configuration of a solid oxide fuel cell according to a first embodiment of the present invention. [Figure 2] 1 is a perspective view of a main part of a solid oxide fuel cell according to a first embodiment of the present invention. [Figure 3] 1 is a schematic diagram showing an example of a solid oxide fuel cell according to a first embodiment (an example in which the central portion of an electrode portion is a concentrated heating region). FIG. [Figure 4] FIG. 4 is a schematic diagram showing another example of the solid oxide fuel cell of the first embodiment (an example in which the outer part of the electrode part is a concentrated heating region). [Figure 5] FIG. 10 is a schematic diagram showing an example of a solid oxide fuel cell according to a second embodiment (an example in which the central portion of an electrode portion is a concentrated heating region). [Figure 6] FIG. 10 is a schematic diagram showing another example of a solid oxide fuel cell according to the second embodiment (an example in which the outer portion of the electrode portion is a concentrated heating region). [Figure 7] FIG. 10 is an explanatory diagram showing the configuration of a solid oxide fuel cell according to a third embodiment of the present invention. [Figure 8] FIG. 10 is an explanatory diagram showing the configuration of a solid oxide fuel cell according to a fourth embodiment of the present invention. [Figure 9] FIG. 10 is an explanatory diagram showing the configuration of a solid oxide fuel cell according to a fifth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0029] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A solid oxide fuel cell according to an embodiment of the present invention will now be described with reference to the accompanying drawings. In the present embodiment, a solid oxide fuel cell used in electronic devices, electric vehicles, etc. will be described as an example.

[0030] (First embodiment) The configuration of a solid oxide fuel cell according to a first embodiment of the present invention will be described with reference to the drawings. Figure 1 is an explanatory diagram showing the configuration of the solid oxide fuel cell according to this embodiment, and Figure 2 is a perspective view of the main part of the solid oxide fuel cell according to this embodiment.

[0031] As shown in Figures 1 and 2, a solid oxide fuel cell 100 of this embodiment includes a flat electrode unit 1 and a flat metal frame 2 that is arranged to sandwich the electrode unit 1 from both sides (top and bottom in Figure 1). The metal frame 2 has an opening in the center (see Figure 2). The electrode unit 1 is composed of a flat electrolyte ceramic 3 (dielectric), and an anode electrode 4 and a cathode electrode 5 that sandwich the electrolyte ceramic 3 from both sides (top and bottom in Figure 1). It can be said that the electrode unit 1 and the metal frame 2 constitute a cell unit 6 (cell configuration).

[0032] The metal frame 2 is in physical contact with the anode electrode 4 and the cathode electrode 5. In the example of FIG. 1, the upper metal frame 2 is in physical contact with the anode electrode 4, and the lower metal frame 2 is in physical contact with the cathode electrode 5. A power supply port 7 is electrically connected to the metal frame 2. A high-frequency oscillator 8 is electrically connected to the power supply port 7, and high-frequency (e.g., microwave) power is supplied from the power supply port 7 to the metal frame 2.

[0033] In the solid oxide fuel cell 100 of this embodiment, the thickness of the electrode unit 1 is configured to be thinner in a predetermined concentrated heating region. The concentrated heating region is a region of the electrode unit 1 that is preset as a region where heating efficiency is low.

[0034] For example, in the example of FIG. 3, a concentrated heating region is set in the center 9 of the electrode unit 1. In this example, the thickness of the electrode unit 1 (the sum of the thicknesses of the anode electrode 4, cathode electrode 5, and electrolyte ceramic 3) is 550 μm at its thinnest position (the center position of the center 9) and 600 μm at its thickest position (the outermost end position of the electrode unit 1). In this way, the thickness of the electrode unit 1 is configured to be thinner at the center 9 (concentrated heating region). More specifically, the thickness of the anode electrode 4 at the thinnest position of the center 9 of the electrode unit 1 is 426 μm, which is thinner than the outermost end of the electrode unit 1 (476 μm thick). The thicknesses of the cathode electrode 5 and the electrolyte ceramic are constant (the thickness of the cathode electrode 5 is 120 μm, and the thickness of the electrolyte ceramic is 4 μm).

[0035] In the example of FIG. 4, a concentrated heating region is set in the outer portion 10 of the electrode unit 1. In this example, the thickness of the electrode unit 1 (the sum of the thicknesses of the anode electrode 4, cathode electrode 5, and electrolyte ceramic 3) is 550 μm at its thinnest position (the outermost end of the outer portion 10) and 600 μm at its thickest position (the center of the electrode unit 1). In this way, the thickness of the electrode unit 1 is configured to be thinner in the outer portion 10 (concentrated heating region). More specifically, the thickness of the anode electrode 4 at the thinnest position of the outer portion 10 of the electrode unit 1 is 426 μm, which is thinner than the thickness of the anode electrode 4 at the center of the electrode unit 1 (476 μm). The thicknesses of the cathode electrode 5 and the electrolyte ceramic are constant (the thickness of the cathode electrode 5 is 120 μm, and the thickness of the electrolyte ceramic is 4 μm).

[0036] The sizes of the anode electrode 4 and the cathode electrode 5 are set larger than the size of the electrolyte ceramic 3. For example, the sizes of the anode electrode 4 and the cathode electrode 5 are 50.4 mm in height and 23.7 mm in width, and the size of the electrolyte ceramic 3 is 49.6 mm in height and 19.8 mm in width. The size of the metal frame 2 is set larger than the sizes of the anode electrode 4 and the cathode electrode 5, and the size of the opening in the metal frame 2 is set smaller than the sizes of the anode electrode 4 and the cathode electrode 5. For example, the size of the metal frame 2 is 65 mm in height and 41 mm in width, and the size of the opening in the metal frame 2 is 48 mm in height and 18 mm in width.

[0037] The sizes of the anode electrode 4, the electrolyte ceramic 3, and the cathode electrode 5 are not limited to those described above. For example, the anode electrode 4 may be 53.5 mm long and 23.5 mm wide, the electrolyte ceramic 3 may be 53.5 mm long and 23.5 mm wide, and the cathode electrode 5 may be 50 mm long and 20 mm wide.

[0038] The anode electrode 4 is made of, for example, NiO (nickel oxide), and the cathode electrode 5 is made of, for example, LSCF (lanthanum-strontium-cobalt-iron) or LSM (lanthanum-strontium-manganese).The electrolyte ceramic 3 is made of, for example, YSZ (yttria-stabilized zirconia) or GDC (gadolinium-doped ceria), and the metal frame 2 is made of, for example, SUS (stainless steel).

[0039] In the solid oxide fuel cell 100 according to the first embodiment of the present invention, when power is supplied from the power supply port 7 to the metal frame 2 arranged around the electrode unit 1, high frequency waves are supplied directly to the electrode unit 1 through the metal frame 2, and the electrode unit 1 is heated by the supplied high frequency waves. In this case, the internal structure (electrode unit 1) is directly heated using the high frequency waves applied to the internal structure, so that the temperature of the internal structure can be raised to a target temperature (operating temperature) with high heating efficiency, in a short time, and with little energy.

[0040] Furthermore, since the thickness of the electrode unit 1 is configured to be thin in a predetermined concentrated heating region, an electric field can be concentrated in the thinned region (concentrated heating region), allowing for concentrated heating. For example, by reducing the thickness of the center 9 of the electrode unit 1 (providing a concentrated heating region in the center 9 of the electrode unit 1), it becomes possible to concentrate heating in the center 9 of the electrode unit 1 and raise the temperature to a high level. Furthermore, by reducing the thickness of the outer portion 10 of the electrode unit 1 (providing a concentrated heating region in the outer portion 10 of the electrode unit), it becomes possible to concentrate heating in the outer portion 10 of the electrode unit 1 and raise the temperature to a high level. The thickness of the electrode unit 1 can be adjusted by changing the thickness of one or more of the materials of the electrolyte ceramic 3, the anode electrode 4, and the cathode electrode 5.

[0041] In this case, if there are areas where the heating effect is high due to conditions such as the mechanical structure of the electrode unit 1 and metal frame 2 and the frequency of the high-frequency power supply, the thickness of the areas where the heating effect is low can be reduced to uniformly heat the electrode unit 1. The concentrated heating areas can be set in advance based on the measurement results by measuring the heating efficiency of the electrode unit 1 in advance.

[0042] (Second embodiment) Next, a solid oxide fuel cell according to a second embodiment of the present invention will be described. Here, the differences between the solid oxide fuel cell according to the second embodiment and the first embodiment will be mainly described. Unless otherwise specified, the configuration and operation of this embodiment are the same as those of the first embodiment.

[0043] In the solid oxide fuel cell 200 of this embodiment, the anode electrode 4 and the cathode electrode 5 have a mesh structure, and the mesh density of the mesh structure in the concentrated heating region is configured to be higher than the mesh density of the mesh structure in regions other than the concentrated heating region.

[0044] For example, in the example of Figure 5, a concentrated heating area is set in the center 9 of the electrode unit 1. In this example, the mesh density of the mesh structure of the anode electrode 4 and the cathode electrode 5 in the center 9 of the electrode unit 1 is 30 m / s, which is configured to be higher than the mesh density (20 m / s) of the mesh structure of the anode electrode 4 and the cathode electrode 5 at the outermost end of the electrode unit 1.

[0045] 6, a concentrated heating region is set in the outer portion 10 of the electrode unit 1. In this example, the mesh density of the mesh structure of the anode electrode 4 and the cathode electrode 5 in the outer portion 10 of the electrode unit 1 is 30 m / s, which is higher than the mesh density (20 m / s) of the mesh structure of the anode electrode 4 and the cathode electrode 5 in the center of the electrode unit 1.

[0046] The solid oxide fuel cell 200 according to the second embodiment of the present invention also provides the same effects as those of the first embodiment.

[0047] In this embodiment, the mesh density of the mesh structure of the anode electrode 4 and the cathode electrode 5 is configured to be high in a predetermined concentrated heating region, so that an electric field can be concentrated in the region with high mesh density (concentrated heating region), allowing for concentrated heating. For example, by increasing the mesh density in the center 9 of the electrode unit 1 (providing a concentrated heating region in the center 9 of the electrode unit 1), it becomes possible to heat the center 9 of the electrode unit 1 in a concentrated manner and raise the temperature. Furthermore, by increasing the mesh density in the outer portion 10 of the electrode unit 1 (providing a concentrated heating region in the outer portion 10 of the electrode unit 1), it becomes possible to heat the outer portion 10 of the electrode unit 1 in a concentrated manner and raise the temperature.

[0048] In this case, if there are areas where the heating effect is high due to conditions such as the mechanical structure of the electrode unit 1 and metal frame 2 and the frequency of the high-frequency power supply, the mesh density of the areas where the heating effect is low can be increased to uniformly heat the electrode unit 1. The concentrated heating areas can be set in advance based on the measurement results, by measuring the heating efficiency of the electrode unit 1 in advance.

[0049] The first and second embodiments may be combined. That is, the thickness of the electrode unit 1 may be configured to be thinner in a predetermined concentrated heating region, and the anode electrode 4 and the cathode electrode 5 may be configured to have a mesh structure, with the mesh density of the mesh structure in the concentrated heating region being higher than the mesh density of the mesh structure in regions other than the concentrated heating region.

[0050] (Third embodiment) Next, a solid oxide fuel cell according to a third embodiment of the present invention will be described. Here, the differences between the solid oxide fuel cell according to the third embodiment and the first embodiment will be mainly described. Unless otherwise specified, the configuration and operation of this embodiment are the same as those of the first embodiment.

[0051] FIG. 7 is an explanatory diagram showing the configuration of a solid oxide fuel cell according to this embodiment. As shown in FIG. 7, in a solid oxide fuel cell 300 according to this embodiment, a plurality of cell units 6 are arranged in series and electrically connected to one another. A gas separator S is disposed between the cell units 6. The separator S is made of, for example, mica. Even when a separator S is provided between the cell units 6, the metal frames 2 of the cell units 6 are electrically connected to one another via a connection C (see FIG. 7). The material of the connection C may be, for example, the same material (metal) as that of the metal frame 2.

[0052] In the solid oxide fuel cell 300 of this embodiment, a plurality of cell units 6 are stacked (laminated) to form one stack unit 11 (stack configuration). The power supply port 7 is electrically connected to the metal frames 2 of the plurality of cell units 6 that are arranged on the outermost sides (the top and bottom sides in FIG. 7), and high-frequency power is supplied from the power supply port 7 to the metal frames 2 arranged on the outermost sides.

[0053] 7, the solid oxide fuel cell 300 of this embodiment includes a temperature sensor 12 that measures the temperature of the electrode unit 1, and a power control unit 13 that controls the high-frequency power supplied to the power supply port 7 in accordance with the temperature of the electrode unit 1. For example, even when heating the electrode unit 1 to 700°C, the high-frequency power required differs between heating from room temperature (25°C) and heating from 400°C. Therefore, the temperature of the electrode unit 1 is measured by the temperature sensor 12, and the power output from the high-frequency oscillator 8 is controlled by the power control unit 13 in accordance with the measured temperature. For example, when the temperature of the electrode unit 1 is low, the output power from the high-frequency oscillator 8 is increased, and when the temperature of the electrode unit 1 is high, the output power from the high-frequency oscillator 8 is decreased.

[0054] The solid oxide fuel cell 300 according to the third embodiment of the present invention also provides the same effects as those of the first embodiment.

[0055] Furthermore, in this embodiment, the high-frequency power supplied to the power supply port 7 is controlled in accordance with the temperature of the electrode unit 1. When the temperature of the electrode unit 1 increases, less high-frequency power needs to be supplied to the power supply port 7 (compared to when the temperature of the electrode unit 1 is low). Therefore, by reducing the high-frequency power supplied to the power supply port 7 in accordance with an increase in the temperature of the electrode unit 1, the total amount of high-frequency power supplied can be reduced. This allows the solid oxide fuel cell 300 to be started efficiently and quickly with the minimum necessary power.

[0056] In this embodiment, the plurality of electrode units 1 arranged in series are electrically connected via the metal frame 2 and the connection part C, and these electrode units 1 can be regarded as a series connection of capacitors in terms of an electrical circuit. Therefore, by supplying power from the power supply port 7 to the metal frame 2 arranged on the outermost side, it becomes possible to supply high-frequency power uniformly to all of the electrode units 1.

[0057] (Fourth embodiment) Next, a solid oxide fuel cell according to a fourth embodiment of the present invention will be described. Here, the differences between the solid oxide fuel cell according to the fourth embodiment and the third embodiment will be mainly described. Unless otherwise specified, the configuration and operation of this embodiment are the same as those of the third embodiment.

[0058] Fig. 8 is an explanatory diagram showing the configuration of a solid oxide fuel cell according to this embodiment. As shown in Fig. 8, a solid oxide fuel cell 400 according to this embodiment includes a pulse drive control unit 14 that pulse-drives a high-frequency oscillator 8 on a time axis. The pulse drive control unit 14 controls the on / off of the high-frequency oscillator 8 at regular time intervals (e.g., 60-second intervals) when heating the solid oxide fuel cell 400 to a predetermined target temperature (e.g., 700°C).

[0059] The solid oxide fuel cell 400 according to the fourth embodiment of the present invention also provides the same effects as those of the first embodiment.

[0060] Furthermore, in this embodiment, the high-frequency oscillator 8 is controlled to be pulse-driven on the time axis (pulse drive control). Even if the high-frequency oscillator 8 is pulse-driven (for example, on-off control), the temperature of the electrode unit 1 can be sufficiently increased by setting the duty ratio of the on-off control so that the temperature increase during the on-time exceeds the temperature decrease during the off-time. When the high-frequency oscillator 8 is on-controlled, high-frequency power is supplied to the power supply port 7, but when the high-frequency oscillator 8 is off-controlled, high-frequency power is not supplied to the power supply port 7. Therefore, the total amount of high-frequency power supplied can be reduced. Furthermore, even if the heated cells are unevenly positioned, the cell temperature is dispersed during the off-time, making the cell temperature uniform. Furthermore, by reducing the continuous operation time of the high-frequency oscillator 8, the life of the high-frequency oscillator 8 can be extended.

[0061] (Fifth embodiment) Next, a solid oxide fuel cell according to a fifth embodiment of the present invention will be described. Here, the differences between the solid oxide fuel cell according to the fifth embodiment and the third embodiment will be mainly described. Unless otherwise specified, the configuration and operation of this embodiment are the same as those of the third embodiment.

[0062] Fig. 9 is an explanatory diagram showing the configuration of a solid oxide fuel cell according to this embodiment. As shown in Fig. 9, a solid oxide fuel cell 500 according to this embodiment includes a plurality of stack units 11 (two in the example of Fig. 9) as destinations of high frequency power. The solid oxide fuel cell 500 according to this embodiment also includes a switch circuit 15 for switching the destination of the high frequency power, and a switch drive control unit 16 for switching the switch circuit 15.

[0063] The switch drive control unit 16 controls the switch circuit 15 to switch the supply destination of the high frequency power at regular time intervals (e.g., every 60 seconds). For example, in the example of Fig. 9, the switch circuit 15 controls so that high frequency power is supplied from the high frequency oscillator 8 to the power supply port 7 of one stack unit 11 (the upper stack unit 11 in Fig. 9) for a certain period of time (e.g., 60 seconds), and then the switch circuit 15 controls so that high frequency power is supplied from the high frequency oscillator 8 to the power supply port 7 of the other stack unit 11 (the lower stack unit 11 in Fig. 9) for the next certain period of time (e.g., 60 seconds).

[0064] The solid oxide fuel cell 500 according to the fifth embodiment of the present invention also provides the same effects as those of the first embodiment.

[0065] Furthermore, in this embodiment, the switch drive control unit 16 controls the switch circuit 15 to switch the destination of the high frequency power supplied from the high frequency oscillator 8 to the power supply port 7 to the power supply port 7 of another solid oxide fuel cell (stack unit 11). This makes it possible to continuously supply high frequency power from one high frequency oscillator 8 to the power supply ports 7 of multiple solid oxide fuel cells (stack units 11) over time. For example, the duty ratio of the switch drive control may be varied according to the temperature difference between the electrode units 1 of the respective solid oxide fuel cells (stack units 11). It may also be varied according to the ratio of the physical sizes of the respective solid oxide fuel cells (stack units 11).

[0066] Although the embodiments of the present invention have been described above by way of example, the scope of the present invention is not limited to these, and can be modified and changed according to the purpose within the scope of the claims. [Industrial Applicability]

[0067] As described above, the solid oxide fuel cell according to the present invention has the advantage of being highly efficient in heating and capable of raising the temperature of the internal structure to a target temperature (operating temperature) in a short time with little energy, and is therefore useful for use in electronic devices, electric vehicles, etc. [Explanation of symbols]

[0068] 1 Electrode part 2 Metal Frame 3. Electrolyte ceramic 4 anode electrode 5. Cathode electrode 6 cell unit (cell configuration) 7 Power Port 8 High Frequency Oscillator 9 Center 10 Outer part 11 Stack Unit (Stack Configuration) 12 Temperature Sensor 13 Power Control Unit 14 Pulse drive control section 15 Switch Circuit 16 Switch drive control section 100, 200, 300, 400, 500 Solid Oxide Fuel Cell

Claims

1. an electrode portion including an electrolyte ceramic and an anode electrode and a cathode electrode sandwiching the electrolyte ceramic from both sides; a metal frame disposed around the electrode portion so as to sandwich the electrode portion from both sides and in physical contact with the anode electrode and the cathode electrode; a power supply port electrically connected to the metal frame for supplying high-frequency power to the metal frame; Equipped with A solid oxide fuel cell, wherein a concentrated heating region is formed by configuring the electrode portion so that a thickness of a portion of the electrode portion is thinner than a thickness of the remaining portion of the electrode portion.

2. 2. The solid oxide fuel cell according to claim 1, wherein the concentrated heating region is a region of the electrode portion that is preset as a region where heating efficiency is low.

3. the anode electrode and the cathode electrode have a mesh structure, 3. The solid oxide fuel cell according to claim 1, wherein the mesh density of the mesh structure in the concentrated heating region is higher than the mesh density of the mesh structure in a region other than the concentrated heating region.

4. 4. The solid oxide fuel cell according to claim 1, wherein the high-frequency oscillator that generates the high-frequency wave includes a power control unit that controls the high-frequency power supplied to the power supply port in accordance with the temperature of the electrode unit.

5. 5. The solid oxide fuel cell according to claim 1, further comprising a pulse drive control section that pulse-drives the high-frequency oscillator that generates the high-frequency wave on a time axis.

6. 6. The solid oxide fuel cell according to claim 5, further comprising: a switch circuit that switches the destination of the high-frequency power supplied from the high-frequency oscillator to the power supply port to the power supply port of another solid oxide fuel cell; and a switch drive control unit that switches the switch circuit.

7. an electrode portion including an electrolyte ceramic and an anode electrode and a cathode electrode sandwiching the electrolyte ceramic from both sides; a metal frame disposed around the electrode portion so as to sandwich the electrode portion from both sides and in physical contact with the anode electrode and the cathode electrode; a power supply port electrically connected to the metal frame for supplying high-frequency power to the metal frame; Equipped with the anode electrode and the cathode electrode have a mesh structure, A solid oxide fuel cell, wherein a mesh density in a portion of the mesh structure is higher than the mesh density in the remaining portion, thereby forming a concentrated heating region.

8. 8. The solid oxide fuel cell according to claim 7, wherein the concentrated heating region is a region of the electrode portion that is preset as a region where heating efficiency is low.

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