Fuel cell system, its operating method, and heated air circulation method

Abstract

Before the fuel cell is activated, the air in the battery chamber is heated to melt any frozen water. [Solution] The fuel cell system 100,200 comprises a battery chamber 60 defined by partition walls 11-16, a fuel cell 1 installed in the battery chamber 60, ducts 20a,20b communicating with the battery chamber 60 through at least one opening 11a,13a and the other opening 11b,13b provided in partition partition walls 11,13 of the partition walls 11-16, and a preheater 3 that supplies heated air. At least the battery chamber 60, one opening 11a,13a and the other opening 11b,13b, and the ducts 20a,20b constitute warm air circulation paths 30A,30B for heated air supplied from the preheater 3.

Description

Technical Field

[0001] The present invention relates to a fuel cell system that operates normally even in a low-temperature environment, a method for operating the fuel cell system, and a method for circulating heated air in the fuel cell system.

Background Art

[0002] A fuel cell that generates electricity through a chemical reaction between hydrogen and oxygen is currently used as a power generation device that does not emit carbon dioxide, such as a power source for households and commercial use, a power source for vehicles, etc. Although water is generated and discharged during the operation of the fuel cell, there is a possibility that some moisture remains inside the fuel cell even when it is stopped. When using the fuel cell in a low-temperature environment such as a cold region or winter, the moisture remaining inside freezes, causing a flooding phenomenon that inhibits the chemical reaction at the electrodes or obstructs the discharge of the generated water, resulting in problems such as the fuel cell being unable to start or malfunctioning when starting.

[0003] Patent Document 1 discloses a hydrogen power generation system (Claims 1 and 10 of Patent Document 1) including a hydrogen generation device, a power generation device (fuel cell) that generates electricity using hydrogen, and a cartridge-type hydrogen storage device that can supply hydrogen to the fuel cell. The waste heat reuse mechanism that warms the outside air drawn in by the waste heat of the fuel cell includes a temperature sensor, a shutter that can open and close an exhaust-side opening, a fan that sends the air in the return duct to the housing through an intake-side opening, and a controller that opens the shutter and drives the fan when the temperature of the outside air is below a predetermined temperature (Claim 11). However, the hydrogen power generation system of Patent Document 1 has no idea of preheating the air inside the housing before the operation of the fuel cell, and there is also no preheater for that purpose.

[0004] Patent Document 2 discloses a fuel cell device having a fuel cell module and auxiliary equipment for operating the fuel cell module within an outer casing, and partitioned into a module storage chamber and an auxiliary equipment storage chamber by a partition member (Patent Document 2, Claim 1). However, since the fuel cell device of Patent Document 2 utilizes the radiant heat of the fuel cell module (Specification 0021), it does not have the idea of ​​preheating the air inside the outer casing before the fuel cell is operated, similar to Patent Document 1, and there is no preheater.

[0005] Patent Document 3 discloses a fuel cell system (Claim 1 of Patent Document 3) comprising a fuel cell, a diaphragm-type air supply unit that takes in air and supplies it to the fuel cell, and a heating unit that heats the air in the space from the air intake to the air supply unit. Patent Document 3 also indicates that the air may be heated by the heating unit prior to the start of operation of the air supply unit (Claim 0028 of the Specification). However, there is no idea to circulate and fill the heated air, and no mechanism for doing so is provided.

[0006] Patent Document 4 discloses a fuel cell power generation device (Claim 1 of Patent Document 4) that includes a fuel cell body, fuel reforming equipment, cooling system equipment, a heater, and a ventilation fan within a package, and prevents the water inside the package from freezing by circulating air heated by the heater inside the package via an air circulation means when power generation operation is stopped. Patent Document 4 indicates that the air heated by the heater is concentrated and directed to the cooling system equipment (Claim 4 of the same document), but does not show the position of the fuel cell body, so there is no idea of ​​warming the surface of the fuel cell housing to melt the frozen water inside it. Since concentrating excessive heating of a specific part of the fuel cell can lead to fuel cell failure, the relative positional relationship between the fuel cell and the heater, and the size of the space inside the package are important. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2021-141058 [Patent Document 2] Japanese Patent Publication No. 2009-205826 [Patent Document 3] International Publication WO2012 / 023261 [Patent Document 4] Japanese Patent Publication No. 2006-140050 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] Therefore, the object of the present invention is to provide a fuel cell system, a method for operating the fuel cell system, and a method for circulating heated air in the fuel cell system, which warm the fuel cell in the battery chamber before the fuel cell is put into operation, in order to solve the problems of the prior art described above. [Means for solving the problem]

[0009] The fuel cell systems 100 and 200 of the present invention comprise a battery chamber 60 defined by partition walls 11-16, a fuel cell 1 installed in the battery chamber 60, ducts 20a and 20b communicating with the battery chamber 60 through at least one opening 11a, 13a and the other opening 11b, 13b provided in partition partition walls 11 and 13 of the partition walls 11-16, and a preheater 3 for supplying heated air. At least the battery chamber 60, one opening 11a, 13a and the other opening 11b, 13b, and the ducts 20a and 20b constitute warm air circulation paths 30A and 30B for the heated air supplied from the preheater 3.

[0010] In the fuel cell systems 100 and 200 of the present invention, during the preliminary operation before activating the fuel cell 1, the preheater 3 sends out heated air, which circulates to the warm air circulation paths 30A and 30B, which consist of at least the battery chamber 60, the openings 11a, 13a, 11b, and 13b on one and the other sides, and the ducts 20a and 20b. In this invention, the battery chamber 60 is filled with heated air before the fuel cell 1 is activated, warming the fuel cell 1 and completely melting any frozen water inside, enabling the fuel cell 1 to operate normally. Furthermore, the warm air circulation prevents air from stagnating, constantly bringing fresh heated air into contact with the housing surfaces 81, 82, 85, and 86 of the fuel cell 1, thereby efficiently liquefying the frozen water inside the fuel cell 1.

[0011] In embodiments of the fuel cell systems 100 and 200, the partition walls 11-16 include a first partition wall 11, a second partition wall 12, a third partition wall 13, and a fourth partition wall 14. Of the four surfaces of the first to fourth partition walls 11-14, two or three surfaces of partition walls 12-14 are in contact with the fuel cell 1, and the remaining two or one surfaces of partition walls 11 and 12 constitute partition wall passages 31 and 32 that allow heated air to flow between them and the fuel cell 1, as part of the warm air circulation paths 30A and 30B. The two or three partition walls 12-14 that are in contact with the fuel cell 1 are made of metal or highly thermally conductive material. The second to fourth partitions 12, 13, and 14 are in contact with the fuel cell 1, and the first partition 11 forms a first partition channel 31 for circulating heated air between itself and the upper surface 81 of the fuel cell 1, as part of the warm air circulation path 30A. The third and fourth partitions 13 and 14 are in contact with the respective sides 83 and 84 of the fuel cell 1, and the warm air circulation path 30B includes a first partition passage 31 for circulating heated air between the first partition 11 and the upper surface 81 of the fuel cell 1, and a second partition passage 32 for circulating heated air between the second partition 12 and the bottom surface 82 of the fuel cell 1. The fuel cell 1 is equipped with a pair of vents 1a and 1b for intake and exhaust, and the pair of vents 1a and 1b and the inside of the fuel cell 1 constitute an internal battery flow path 36 through which heated air passes, as part of the warm air circulation paths 30A and 30B. The system includes an opening / closing device 8 that opens or closes one opening 11a, 13a or / or the other opening 11b, 13b of the partition walls 11, 13 to connect or block the warm air circulation passages 30A, 30B. The partition walls 11-16 include a fifth partition wall 15 and a sixth partition wall 16 facing each other, and the fifth and sixth partition walls 15 and 16 each have ventilation openings 15a and 16a, respectively. The preheater 3 is installed in one of the openings 11a and 13a or the other openings 11b and 13b of the partition walls 11 and 13, or between the ventilation openings 15a and 16a of the fifth or sixth partition wall 15 and 16 and the fuel cell 1. The battery chamber 60 includes a space 65 between the fifth partition wall 15 and the fuel cell 1, and another space 66 between the sixth partition wall 16 and the fuel cell 1. The preheater 3 is provided in one of the openings 11a located on the side of space 65, and the outlet 3a of the preheater 3 is located in space 65, which has a smaller volume than the other space 66. The battery chamber 60 includes a space 65 between the fifth partition wall 15 and the fuel cell 1, and another space 66 between the sixth partition wall 16 and the fuel cell 1. The preheater 3 is located in the other space 66, which has a smaller volume than the first space 65, and is positioned between the ventilation opening 16a of the sixth partition wall 16 and the fuel cell 1. The fifth partition 15 is equipped with a shutter to open or close the ventilation opening 15a and / or the sixth partition 16's ventilation opening 16a.

[0012] The operating method of the fuel cell systems 100, 200 of the present invention includes the steps of: when starting up the fuel cell systems 100, 200, activating the preheater 3 to circulate heated air in the warm air circulation paths 30A, 30B if the measured temperature of the battery chamber 60 is below a first temperature; and activating the fuel cell 1 to start generating power when a certain amount of time has elapsed and / or the measured temperature of the battery chamber 60 has reached a second temperature or higher after circulating the heated air in the warm air circulation paths 30A, 30B.

[0013] The operating method of the fuel cell systems 100 and 200 of the present invention involves, when the fuel cell system is started, activating the preheater 3 if the battery chamber 60 is below a specific first temperature, and filling the battery chamber 60 with heated air through circulation. Subsequently, when the operating time of the preheater 3 is reached and / or the temperature inside the battery chamber 60 is reached, which is expected to completely melt the frozen water inside the fuel cell 1, the operation of the fuel cell 1 is started. This prevents failure of the fuel cell 1 due to water freezing.

[0014] In an embodiment of the operation method of the fuel cell systems 100 and 200, the process of circulating the heated air in the heating air circulation paths 30A and 30B includes at least filling the upper space 61 between the upper partition wall 11 of the partition wall and the fuel cell 1, the empty space 65 between the front partition wall 15 of the partition wall and the fuel cell 1, and the rear space 66 between the rear partition wall 16 of the partition wall and the fuel cell 1 with the heated air, and contacting the heated air with the surfaces 81, 85, and 86 of the fuel cell 1.

[0015] In the method of circulating the heated air according to the present invention, in the method of circulating the heated air in the fuel cell system 100, the heated air sent out from the preheater 3 provided at one opening 11a of the first partition wall 11 flows through the first heating air circulation path 30A that passes through the empty space 65 in the battery chamber 60, the upper surface 81 and the interior of the fuel cell 1, the other space 66 in the battery chamber 60, the other opening 11b of the first partition wall 11, and the upper duct 20a communicating with the first partition wall 11, and returns to the one opening 11a.

[0016] In the method of circulating the heated air according to the present invention, in the method of circulating the heated air in the fuel cell system 200, the heated air sent out from the preheater 3 provided in the other space 66 of the battery chamber 60 flows through the second heating air circulation path 30B that passes through the other space 66, the upper surface 81, the bottom surface 82, and the interior of the fuel cell 1, the empty space 65 in the battery chamber 60, one opening 13a of the third partition wall 13, the side duct 20b communicating with the third partition wall 13, and the other opening 13b of the third partition wall 13, and returns to the other space 66.

Effect of the Invention

[0017] In the fuel cell system, its operation method, and the method of circulating the heated air according to the present invention, before starting the fuel cell, the frozen water inside the fuel cell can be melted by heating, and the fuel cell can be normally operated without failure. Therefore, the present invention is optimal for using the fuel cell in a low-temperature environment.

Brief Description of the Drawings

[0018] [Figure 1] Plan view schematically showing the first embodiment of the fuel cell system of the present invention [Figure 2]Cross-sectional view schematically showing the cross-section along line A-A in FIG. 1 [Figure 3] Cross-sectional view schematically showing the cross-section along line B-B in FIG. 1 [Figure 4] Plan view schematically showing a second embodiment of the fuel cell system of the present invention [Figure 5] Cross-sectional view schematically showing the cross-section along line C-C in FIG. 4 [Figure 6] Cross-sectional view schematically showing the cross-section along line D-D in FIG. 4

Mode for Carrying Out the Invention

[0019] Hereinafter, embodiments of the fuel cell system of the present invention, its operation method, and the method of circulating heated air will be described with reference to FIGS. 1 to 6. The following descriptions of the embodiments, examples, and drawings are illustrative and do not limit the present invention. Also, FIGS. 1 to 6 are all drawings shown in a simplified manner for easy understanding of the present invention.

[0020] The fuel cell systems 100 and 200 of the present invention include a hollow battery chamber 60 defined by six-sided partition walls 11 - 16, a box-shaped fuel cell 1 installed in the battery chamber 60, ducts 20a and 20b that communicate with the battery chamber 60 through at least one of the partition walls 11 and 13 among the partition walls 11 - 16 and the openings 11a, 13a, 11b, 13b on the other side, and a preheater 3 that sends out heated air before the operation (or startup or activation) of the fuel cell 1. At least the battery chamber 60, the openings 11a, 13a, 11b, 13b of the partition walls 11 and 13, and the ducts 20a and 20b constitute warm air circulation paths 30A and 30B through which heated air circulates.

[0021] In this invention, during the pre-operation before the fuel cell 1 is turned on, heated air circulates through the warm air circulation paths 30A and 30B to fill the battery chamber 60 with heated air. This heats the surfaces 81, 82, 85, and 86 of the fuel cell 1 in a low-temperature environment, melting any frozen water inside, and enabling the normal operation of the fuel cell 1 after the water has completely melted. The warm air circulation paths 30A and 30B may be either vertical circulation (Figure 2), which forms a substantially vertical circulation surface (rotates vertically), or horizontal circulation (Figure 4), which forms a substantially horizontal circulation surface (rotates horizontally). Furthermore, the circulation (rotation) direction may be either clockwise or counterclockwise.

[0022] The fuel cell 1 used in the present invention is also referred to as a fuel cell device, fuel cell body, fuel cell module, or fuel cell box, and includes a cell stack in which a plurality of cells are stacked inside its housing. Each cell comprises an electrolyte in the form of an ion exchange membrane, a negative electrode (fuel electrode) and a positive electrode (oxygen electrode) to which hydrogen and air (oxygen) are supplied on both sides of the electrolyte, and a pair of separators that sandwich the electrolyte, negative electrode, and positive electrode and form a boundary between the cells. In Figures 2, 3, 5, and 6, the internal structure of the fuel cell 1 is shown in cross-sectional form (hatching) for the sake of simplicity in the description. In the present invention, a polymer electrolyte fuel cell (PEFC) using an ion exchange membrane is used, but any type of fuel cell may be used, such as a phosphoric acid fuel cell (PAFC), molten carbonate fuel cell (MCFC), solid oxide fuel cell (SOFC), alkaline electrolyte fuel cell (AFC), direct-acting fuel cell (DFC), or biofuel cell (BFC). Fuel cell 1 receives hydrogen from a hydrogen storage device (hydrogen storage alloy) (not shown), and the electricity generated by fuel cell 1 is supplied to a storage battery and a load (power consumption device) via power lines.

[0023] In this embodiment, the partition wall comprises a first partition wall (upper partition wall) 11 that forms the ceiling of the battery compartment 60, a second partition wall (bottom partition wall) 12 that faces the first partition wall 11 and forms the bottom surface 82 of the battery compartment 60, a third partition wall (left partition wall) 13 that forms one side wall of the battery compartment 60 (the left wall in Figures 3 and 6), and a fourth partition wall (right partition wall) 14 that faces the third partition wall 13 and forms the other side wall of the battery compartment 60 (the right wall in Figures 3 and 6).

[0024] As will be described later, in the first embodiment (fuel cell system 100), the first partition wall 11 has openings 11a and 11b on one and the other side (Figure 2), and heated air is passed between the battery chamber 60 and the upper duct 20a. In the second embodiment (fuel cell system 200), the third partition wall 13 has openings 13a and 13b on one and the other side (Figure 5), and heated air is passed between the battery chamber 60 and the side duct 20b. The second partition wall 12 and the fourth to sixth partition walls 14-16, other than the first and third partition walls 11 and 13, may also be used as partition walls. Opaque materials, or transparent or translucent materials that allow the interior to be seen, are used for the partition walls 11-14.

[0025] The partition walls 11 and 13 can be provided with two, three or more, or a large number of openings 11a, 13a, 11b, and 13b, as long as heated air can pass through and circulate. The cross-sectional shape of the openings 11a, 13a, 11b, and 13b is not particularly limited and can be rectangular, polygonal, circular, etc. The length L2 between the openings 11a, 13a, 11b, and 13b on one side and the other side is formed to be longer than the depth L1 between the front and rear of the fuel cell 1. This makes it easier for the circulating heated air to come into contact with the surface of the fuel cell 1, especially the front 85 and rear 86.

[0026] The partition walls 11 and 13 are equipped with an opening / closing device 8 that opens or closes one opening 11a, 13a or / and the other opening 11b, 13b to connect or block the warm air circulation passages 30A and 30B. The opening / closing device 8 is not limited as long as it can open and close the openings 11a, 13a, 11b, and 13b; for example, an opening / closing device 8 that uses a solenoid to reciprocate a closing plate (Figures 1 and 4), a gas valve, etc., can be used. When the preheater 3 is activated (or started or running), one opening 11a, 13a or / and the other opening 11b, 13b is opened automatically (e.g., by a command from a control device) or manually by the opening / closing device 8, or if already open, it is kept open to circulate heated air through the warm air circulation passages 30A and 30B. On the other hand, after the battery chamber 60 is sufficiently filled with heated air, the preheater 3 can be stopped and the openings 11a, 13a, 11b, and 13b can be closed by the opening / closing device 8 to maintain the temperature of the battery chamber 60.

[0027] Ducts 20a and 20b are formed on the side opposite the battery chamber 60, with the partition walls 11 and 13 in between, extending along the entire length L of the fuel cell systems 100 and 200, and / or along the depth L1 between the front and rear of the fuel cell 1, with a length longer than the depth L1 (Figures 2 and 4). Ducts 20a and 20b facilitate the circulation of heated air. The cross-sectional shape of ducts 20a and 20b is not limited and may be rectangular (Figures 3 and 6), polygonal, circular, elliptical, etc.

[0028] In this invention, of the two pairs of four opposing first to fourth partition walls 11-14, any two or three partition walls are in contact with, surface-contact with, or abut against the fuel cell 1, while the remaining two or one partition wall forms first and second partition wall flow paths 31, 32 for circulating heated air between itself and the surface of the fuel cell 1, as part of the first warm air circulation paths 30A, 30B. As a result, the two or three partition walls in contact with the fuel cell 1 are in contact with each surface of the fuel cell 1 without forming a flow path, and the opposite side of the fuel cell 1 is abutted against and surrounded by the heat-generating elements 42, 43, 44 (hatched in Figures 3 and 6). In the case of the two- or three-sided partition walls, the two partition walls are shown as the third and fourth partition walls 13 and 14 in Figure 6, but are not limited to these, and may be any of the first and second partition walls 11 and 12, the first and third partition walls 11 and 13, the first and fourth partition walls 11 and 14, the second and third partition walls 12 and 13, or the second and fourth partition walls 12 and 14. Similarly, the three partition walls of the two- or three-sided partition walls are shown as the second to fourth partition walls 12-14 in Figure 3, but are not limited to these, and may be any of the first to third partition walls 11-13, the first, second and fourth partition walls 11, 12, and 14, or the first, third and fourth partition walls 11, 13, and 14.

[0029] Of the four sides, the remaining two or one side of the partition wall forms first and second partition wall channels 31 and 32 between the fuel cell 1 and the partition wall. The partition walls of the remaining two sides are shown as first and second partition walls 11 and 12 in Figure 5, but are not limited to these; they may be first and third partition walls 11 and 13, first and fourth partition walls 11 and 14, second and third partition walls 12 and 13, second and fourth partition walls 12 and 14, or third and fourth partition walls 13 and 14, and first and second partition wall channels may be formed between any of these and the fuel cell 1. The partition wall of the remaining one side is shown as first partition wall 11 in Figure 2, but are not limited to this; they may be second, third, or fourth partition walls 12, 13, or 14, and a first partition wall channel may be formed between any of these and the fuel cell 1.

[0030] The heat-generating elements 42, 43, and 44 surrounding the fuel cell 1 are devices, equipment, fixtures, components, piping, etc., that generate or retain heat, such as a battery, control panel, hydrogen storage device, and hydrogen piping group. The battery stores electricity obtained from the fuel cell 1 and solar cells (not shown), and also starts up together with the fuel cell systems 100 and 200 to measure the amount of stored electricity, so it becomes hotter than the ambient temperature in a low-temperature environment. When the power to the fuel cell systems 100 and 200 is turned on, the control panel's built-in power supply, electrical equipment, control device, etc., activates and generates heat even before the fuel cell 1 starts up. The hydrogen storage device heats the hydrogen storage alloy to release hydrogen, so it becomes hot even before hydrogen is released (before the fuel cell 1 starts up). The hydrogen piping group is piping that contains hydrogen released from the hydrogen storage device, so it becomes relatively hot.

[0031] The presence of two or three partition walls 12-14 in contact with the surface 82-84 of the fuel cell 1 prevents the fuel cell 1 from being directly exposed to low-temperature outside air. Furthermore, the partition walls 12-14 and the heat-generating elements 42, 43, and 44 closely attached to them provide insulation, preventing heat loss and thus preventing the water inside the fuel cell 1 from freezing. Additionally, during the preliminary operation before the fuel cell 1 is put into service, heating (heat transfer) from the heat-generating elements 42, 43, and 44, which are in contact with the fuel cell 1 on the opposite side of the partition walls 12-14, warms the partition walls 12-14 and the surface 82-84 of the fuel cell 1. Combined with heating by the preheater 3, this warms the water inside the fuel cell 1 that is frozen. This contact structure allows for a reduction in power consumption by the preheater 3 in this invention.

[0032] The two or three partition walls 12-14 that are in contact with the fuel cell 1 are made of flat metal members or highly thermally conductive members. This allows heat to be efficiently transferred to the fuel cell 1 from the heat-generating elements 42, 43, 44, such as the storage battery 2, control panel, and / or hydrogen piping group, which are operating and generating heat before the fuel cell 1 is put into operation, through the partition walls 12-14 in contact with the fuel cell 1.

[0033] The partition wall further includes a fifth partition wall (front partition wall) 15 that forms the front wall of the battery chamber 60, and a sixth partition wall (back partition wall) 16 that forms the back wall of the battery chamber 60 opposite the fifth partition wall 15. The fifth and sixth partition walls 15 and 16 are also the outer walls of the fuel cell systems 100 and 200, respectively, and have ventilation openings 15a and 16a for exchanging the air in the battery chamber 60 with outside air. The fifth and sixth partition walls 15 and 16 can be made of opaque material, or transparent or translucent material that allows the interior to be seen.

[0034] The battery chamber 60 is a space surrounded by the first to sixth partition walls 11-16, where the fuel cell 1 is located. As shown in Figures 2 and 5, it includes a front space 65 formed between the fuel cell 1 and the fifth partition wall 15, a back space 66 formed between the fuel cell 1 and the sixth partition wall 16, and an upper space 61 formed between the fuel cell 1 and the first partition wall 11. Heated air circulates and fills the front space 65, the other space 66, and the upper space 61, warming the front 85, back 86, and top surface 81 of the fuel cell 1, thereby promoting the melting of the frozen water in the fuel cell 1. By providing space in the battery chamber 60, a larger volume of heated air can be stored.

[0035] The preheaters 3 are provided in one or more locations at the openings 11a, 13a, 11b, and 13b of the partition walls 11 and 13, or between the ventilation openings 15a and 16a of the fifth or sixth partition walls 15 and 16 and the fuel cell 1. By providing the preheaters 3 at the openings 11a, 13a, 11b, and 13b, the circulating heated air is heated efficiently, resulting in significant energy savings. On the other hand, by providing the preheaters between the ventilation openings 15a and 16a and the fuel cell 1, heating can be done while taking in a large amount of fresh outside air, and the battery chamber 60 and ducts 20a and 20b can be effectively ventilated. The installation location of the preheaters 3 is not limited; for example, they may be installed outside the fuel cell systems 100 and 200 and heated air may be blown into the battery chamber 60 through pipes or the like. The number of preheaters 3 is not limited, and one or more may be used. Furthermore, while the preheater 3 is preferably integrated with the blower fan, it may also be a separate unit, meaning the blower fan is independently positioned at a different location.

[0036] The fuel cell systems 100 and 200 may be equipped with shutters (not shown) that open or close the ventilation openings 15a and 16a of the fifth and / or sixth partition walls 15 and 16. By closing the ventilation openings 15a and 16a with shutters, the battery chamber 60 can be kept warm after being filled with heated air, and the battery chamber 60 can be insulated even when the fuel cell 1 is stopped, thereby preventing the freezing of moisture. The fuel cell systems 100 and 200 also include, although not shown, a temperature sensor for measuring the temperature of the battery chamber 60 and a control device that controls the operation of the preheater 3, fuel cell 1, switchgear 8, shutters, etc., according to the temperature measured by the temperature sensor. The temperature sensor is provided inside or on the surface 81-86 of the fuel cell 1, on the inner or outer surface of the partition walls 11-16, or in the ducts 20a and 20b. The temperature sensor and control device may be installed not only inside but also outside the fuel cell systems 100 and 200.

[0037] The fuel cell system 100 of the first embodiment will be described in detail below with reference to Figures 1 to 3. The same configuration as described above will not be explained in this embodiment. Figure 1 is a schematic plan view of the fuel cell system 100 of the first embodiment, showing the upper cover 51 removed. Figures 2 and 3 are schematic cross-sectional views showing the cross-section along lines AA and BB in Figure 1, respectively.

[0038] The fuel cell system 100 shown in Figures 1 to 3 comprises a battery chamber 60 whose space is defined by six partition walls 11-16, a fuel cell 1 installed on the second partition wall (bottom partition wall) 12 of the battery chamber 60, a first partition wall (partition partition wall) 11 forming the ceiling surface of the battery chamber 60, one and the other openings 11a, 11b provided in the partition partition wall 11, an upper duct 20a communicating with the battery chamber 60 through the one and the other openings 11a, 11b, and a preheater 3 with an integrated blower fan provided in one of the openings 11a to send heated air toward the battery chamber 60 before the fuel cell 1 is activated. At least the battery chamber 60, the one and the other openings 11a, 11b, and the upper duct 20a constitute a vertical circulation first warm air circulation path 30A shown in Figure 2, through which the heated air sent from the preheater 3 flows.

[0039] As shown in Figure 3, the fuel cell system 100 has three surfaces, the second partition wall 12, the third partition wall 13, and the fourth partition wall 14, that are in contact with the bottom surface 82 and both sides 83 and 84 of the fuel cell 1. The second, third, and fourth partition walls 12, 13, and 14, which are made of metal or high thermal conductivity material, have surfaces opposite to the fuel cell 1 that are in contact with heat-generating elements, namely the battery 42, the control panel 43, and the hydrogen piping group 44, respectively. At least the battery 42, which is in a charged state, and the control panel 43 after the fuel cell system 100 has been started, generate heat even before the fuel cell 1 is activated. Therefore, due to this heat transfer, in conjunction with the heating by the preheater 3, the entire surface 81-86 of the fuel cell 1 is warmed, and the frozen water inside is accelerated to melt. Furthermore, if the hydrogen piping group 44 is located adjacent to or near the hydrogen storage device, the hydrogen piping group 44 will be heated together with the hydrogen storage device, and contact between the hydrogen piping group 44 and the second partition wall 12 will also promote the thawing of frozen water before the fuel cell 1 is activated.

[0040] The first partition wall (partition wall) 11 of the fuel cell system 100 defines an upper space 61 in the battery chamber 60 between it and the fuel cell 1. In the upper space 61, a first partition wall flow path 31 (Figure 2) is formed as part of the warm air circulation path 30A through which heated air from the preheater 3 flows. The heated air passing through the first partition wall flow path 31 in the upper space 61 warms the upper surface 81 of the fuel cell 1 in particular before it is put into operation. Furthermore, since the first partition wall flow path 31 is formed by branching off (approximately perpendicular to) the flow path in the direction of discharge from the preheater 3, it has the effect of dispersing the extremely hot air immediately after it is discharged from the preheater 3.

[0041] The fuel cell 1 mounted on the second bulkhead 12 shown in Figure 2 is equipped with a pair of intake and exhaust vents 1a and 1b on the front 85 and rear 86 of the fuel cell 1, and an internal flow path 36 within the battery, which runs from one (intake side) vent 1a through the inside of the fuel cell 1 to the other (exhaust side) vent 1b, is configured as part of the first warm air circulation path 30A. A portion of the heated air flowing through the warm air circulation path 30A passes through the inside of the fuel cell 1 before operation, effectively melting any frozen water remaining in the cells or drain pipes within the fuel cell 1.

[0042] In the battery chamber 60 shown in Figure 2, the other space (back space) 66 between the sixth partition wall 16 and the back of the fuel cell 1 86 has a larger volume than the one space (front space) 65 between the fifth partition wall 15 and the front surface 85 of the fuel cell 1. A preheater 3 is installed in one of the openings 11a on the side of the smaller space 65, and the outlet 3a of the preheater 3 is positioned in the smaller space 65 to promote the flow of the extremely hot air immediately after heating, which is sent from the preheater 3 toward the space 65, without causing it to stagnate in the space 65.

[0043] To provide the outlet 3a of the preheater 3 in a small-capacity space 65, the flow velocity of the extremely hot air is increased, shortening the contact time with the front surface 85 of the fuel cell 1, thereby preventing excessive heating concentration on the front surface 85 of the fuel cell 1 and the resulting failure of the fuel cell 1. In addition, a large-volume other space 66 is provided distal to the preheater 3, so that the incoming hot air is not immediately flowed but is homogenized in the other space 66 to generate heated air at an appropriate temperature. The large-capacity other space 66 functions as a space for storing a large amount of homogenized heated air at an appropriate temperature. Therefore, in this embodiment, the relative positional relationship between the fuel cell 1 and the preheater 3, and the relative size of the space 65 and the other space 66 are clearly defined, and the problems of the conventional technology (fuel cell power generation device of Patent Document 4) can be solved.

[0044] As shown in Figure 2, the upper duct 20a of the fuel cell system 100 is formed on the partition wall (first partition wall) 11 on the side opposite the battery chamber 60, along the entire length L of the fuel cell system 100 and along the depth L1 of the fuel cell 1, and is longer than the depth L1. The upper duct 20a is a space surrounded or defined by the first partition wall 11, the third to sixth partition walls 13-16 and the upper cover 51, and constitutes a warm air circulation path 30A that returns heated air received from the other space 66 of the battery chamber 60 through the other opening 11b to one space 65 of the battery chamber 60 through the one opening 11a. The other opening 11b of the partition wall (first partition wall) 11 is equipped with an opening / closing device 8 for connecting or disconnecting the warm air circulation path 30A.

[0045] Next, the fuel cell system 200 of the second embodiment will be described in detail with reference to Figures 4 to 6. The same configuration as described above will not be explained in this embodiment. Figure 4 is a schematic plan view of the fuel cell system 200 of the second embodiment, showing the upper cover 51 removed. Figures 5 and 6 are schematic cross-sectional views showing the CC and DD lines of the cross-section in Figure 4, respectively.

[0046] The fuel cell system 200 shown in Figures 4 to 6 comprises a battery chamber 60 whose space is defined by six partition walls 11-16, a fuel cell 1 installed on a second partition wall (bottom partition wall) 12 of the battery chamber 60 via a support part 72, a third partition wall (partition partition wall) 13 forming one side wall of the battery chamber 60, openings 13a and 13b provided in the partition partition wall 13, a side duct 20b communicating with the battery chamber 60 through the openings 13a and 13b, and a preheater 3 with an integrated blower fan provided in the other space 66 of the battery chamber 60 to send heated air towards the rear 86 of the fuel cell 1 before the fuel cell 1 is put into operation. At least the battery chamber 60, the openings 13a and 13b on one and the other, and the side duct 20b constitute a second warm air circulation path 30B in a lateral circulation configuration as shown in Figure 4, through which heated air sent from the preheater 3 flows.

[0047] As shown in Figure 4, the fuel cell system 200 has a third partition wall 13 and a fourth partition wall 14 that are in contact with the respective sides 83 and 84 of the fuel cell 1. On the other hand, as shown in Figure 5, as part of the second warm air circulation path 30B, the first partition wall 11 forms a first partition wall flow path 31 in the upper space 61 between it and the upper surface 81 of the fuel cell 1, and the second partition wall 12 forms a second partition wall flow path 32 in the bottom space 62 between it and the bottom surface 82 of the fuel cell 1. The bottom surface 82 of the fuel cell 1 is provided with a support part 72 that supports the fuel cell 1 and is fixed to the second partition wall 12. The support part 72 extends along the depth L1 of the fuel cell 1 and forms the bottom space 62 (Figures 5 and 6), and the bottom space 62 constitutes the second partition wall flow path 32 through which heated air flows, as part of the second warm air circulation path 30B. When heated air flows through the second partition channel 32, it can warm the bottom surface 82 of the fuel cell 1, and in particular can melt frozen water in the drain pipe located at the bottom of the fuel cell 1.

[0048] In the fuel cell system 200, as shown in Figures 4 and 5, the volume of the other space (back space) 66 between the sixth partition wall 16 and the fuel cell 1 is smaller than the volume of the one space (front space) 65 between the fifth partition wall 15 and the fuel cell 1. The preheater 3 is installed in the other space 66, which has a smaller volume than the one space 65, and is fixedly supported by the second partition wall 12 between the ventilation opening 16a of the sixth partition wall 16 and the fuel cell 1. It may also be fixedly supported by any of the partition walls 11-14, 16 or the fuel cell 1. The outlet 3a of the preheater 3 is directed towards the fuel cell 1.

[0049] Since the preheater 3 is located in the smaller-volume other space 66, the extremely hot air immediately after heating from the preheater 3 does not stagnate in the small-volume other space 66, as shown in Figure 5. Instead, it flows at high velocity through the first partition channel 31 in the upper space 61, the internal battery channel 36 that passes from the other (intake side) vent 1b through the inside of the fuel cell 1 to the one (exhaust side) vent 1a, and the second partition channel 32 in the bottom space 62, and is supplied to the one space 65. In the large-capacity one space 65 distal to the preheater 3, the incoming hot air is not immediately allowed to flow but is homogenized in the one space 65 to generate heated air at the appropriate temperature. Furthermore, the large-capacity one space 65 functions as a space for storing a large amount of homogenized heated air at the appropriate temperature.

[0050] In other words, in this embodiment, the relative positional relationship between the fuel cell 1 and the preheater 3, and the relative size of one space 65 and the other space 66 are clearly defined, and the surface 81-86 of the fuel cell 1 housing is heated to melt the frozen water inside. Figure 4 shows two preheaters 3 arranged in parallel, but there are no restrictions on the number or arrangement method, and one or more preheaters 3 can be arranged in series, in parallel, or in other appropriate positions.

[0051] As shown in Figures 4 and 5, the side duct 20b of the fuel cell system 200 is formed on the side opposite the battery chamber 60, across the partition wall (third partition wall) 13, along the entire length L of the fuel cell system 200 and along the depth L1 of the fuel cell 1, with the duct being longer than the depth L1. The side duct 20b is a space formed adjacent to the heat-generating element 43, and it returns heated air received from one space 65 of the battery chamber 60 through one opening 13a to the other space 66 of the battery chamber 60 through the other opening 13b. In this embodiment, the side duct 20b is provided only on the left side (Figure 6), but it may also be provided only on the right side, or on both the left and right sides.

[0052] The following describes in detail the operating method of the fuel cell systems 100 and 200 according to the present invention.

[0053] First, the fuel cell systems 100 and 200 are started, and the temperature inside the battery chamber 60 or outside the fuel cell systems 100 and 200 is measured by a temperature sensor (not shown). If the measured temperature is below the first temperature, the control device (not shown) that receives the measured temperature signal sends a start signal to the preheater 3, which is integrated with a blower fan, to start the preheater 3 and circulate the heated air in the warm air circulation paths 30A and 30B. There are no restrictions on the first temperature, but it is, for example, any temperature below 10°C, preferably 5°C, 4°C, 3°C, 2°C, 1°C, 0°C, -1°C, -2°C, -3°C, -4°C, or -5°C. When the fuel cell systems 100 and 200 are started, the heat-generating elements surrounding the fuel cell 1, such as the storage battery 42, control panel 43, and hydrogen generator, also start and generate heat.

[0054] In the fuel cell system 100, heated air is circulated through warm air circulation paths 30A and 30B to fill the upper space 61 between the upper partition wall (first partition wall) 11 and the fuel cell 1, the one space 65 between the front partition wall (fifth partition wall) 15 and the fuel cell 1, and the other space 66 between the back partition wall (sixth partition wall) 16 and the fuel cell 1 with heated air. In the fuel cell system 200, the bottom space 62 between the bottom partition wall (second partition wall) 12 and the fuel cell 1 is further filled with heated air. The filled heated air comes into contact with the surfaces 81, 82, 85, and 86 of the fuel cell 1, warming these surfaces. Heat is also transferred from the heat-generating elements 42, 43, and 44 to the surfaces 82, 83, and 84 of the fuel cell 1 via the partition walls 12, 13, and 14.

[0055] Next, when a certain amount of time has elapsed since the preheater 3 was started (either at the time of or after the time elapsed) and / or when the measured temperature of the battery chamber 60 reaches or exceeds the second temperature (either at the time of or after the temperature reaches or exceeds the second temperature), the control device sends a stop signal to the preheater 3 to stop the preheater 3. After confirming that the preheater 3 has stopped, the control device sends a start signal to the fuel cell 1 to officially start the fuel cell 1. The aforementioned certain amount of time is not limited as long as it is the time it takes for the frozen water in the fuel cell 1 to melt, but can be set to any time between 1 minute and 30 minutes, for example. The second temperature is not limited as long as it is a temperature higher than or equal to the set first temperature, but can be any temperature above 5°C, for example. Alternatively, before the preheater 3 is stopped, i.e., while it is running, the control device may send a start signal to the fuel cell 1 to start the fuel cell 1. In this case, the fuel cell 1 may be started when a certain amount of time has elapsed or after the preheater 3 has been started, and the preheater 3 may be stopped when or after the measured temperature of the battery chamber 60 reaches or exceeds the second temperature. Alternatively, after the preheater 3 is started, the fuel cell 1 may be operated when the measured temperature of the battery chamber 60 reaches or exceeds the second temperature, or thereafter, and the preheater 3 may be stopped after a certain period of time has elapsed since the preheater 3 was started.

[0056] While the fuel cell 1 is in operation, it starts generating electricity through the reaction between hydrogen supplied from the hydrogen generator to the negative electrode (fuel electrode) via the hydrogen piping group 44 and oxygen supplied from the atmosphere to the positive electrode (oxygen electrode), and transmits the electricity to the storage battery 42 or power-consuming devices such as household appliances. If the ambient temperature drops below the first temperature again while the fuel cell 1 is in operation, the preheater 3 may be restarted.

[0057] Subsequently, the control devices of the fuel cell systems 100 and 200 stop the operation of the fuel cell 1 and the fuel cell systems 100 and 200 after receiving specific signals, such as a signal indicating that the charge level of the battery 42 has exceeded a certain value, a stop signal from the driver / manager, or a fault signal from the fuel cell 1.

[0058] The following describes in detail the method for circulating heated air in the fuel cell system according to the present invention.

[0059] In the heating air circulation method of the fuel cell system 100 (first embodiment), after the fuel cell system 100 is started (or activated or running) but before the fuel cell 1 is started, the control device (not shown) of the fuel cell system 100 starts a preheater 3 with an integrated blower fan, and the preheater 3 sends heated air from the outlet 3a in the direction of one space 65. The heated air sent from the preheater 3, which is provided in one opening 11a of the first partition wall 11, flows through one space (front space) 65 of the battery chamber 60, the top surface 81 and the interior of the fuel cell 1, the other space (back space) 66 of the battery chamber 60, the other opening 11b of the first partition wall 11, and the upper duct 20a communicating with the first partition wall 11, returning to the one opening 11a, through the first warm air circulation path 30A. As a result, in a low-temperature environment, each surface of the fuel cell 1 (the top surface 81, the front surface 85, and the back surface 86 in this first embodiment) is heated, and the frozen water inside is melted.

[0060] In the heating air circulation method of the fuel cell system 200 (second embodiment), after the fuel cell system 100 is started (or activated or running) and before the fuel cell 1 is started, the control device (not shown) of the fuel cell system 200 starts a preheater 3 with an integrated blower fan, and the preheater 3 sends heated air from the outlet 3a toward the fuel cell 1. The heated air sent from the pair of preheaters 3 provided in the other space 66 of the battery chamber 60 flows through the other space 66, the top surface 81 and bottom surface 82 and the interior of the fuel cell 1, one space 65 of the battery chamber 60, one opening 13a of the third partition wall 13, the side duct 20b communicating from the third partition wall 13, and the other opening 13b of the third partition wall 13, returning to the other space 66, through the second warm air circulation path 30B. As a result, in a low-temperature environment, each surface of the fuel cell 1 (the top surface 81, bottom surface 82, front surface 85, and back surface 86 in this second embodiment) is heated, and the frozen water inside is melted. [Industrial applicability]

[0061] The present invention is widely applicable in environments where air is present. For example, it can be widely used as a power source for both normal and emergency use in residences, office buildings, factories, schools, hospitals, streetlights, traffic signals, emergency equipment, infrastructure facilities, commercial facilities, amusement facilities, neon advertisements, remote areas, mountain cabins, remote islands, inside space stations, lunar facilities, etc. It can also be widely used as a power source for passenger cars, motorcycles, buses, trucks, trains, ships, submarines, aircraft, rockets, artificial satellites, etc., as well as for the fuel cell system, its operating method, and heated air circulation method according to the present invention. [Explanation of Symbols]

[0062] 1...Fuel cell, 1a, 1b...Pair of vents, 3...Preheater, 3a...Outlet, 8...Switching device, 11...First partition wall, 12...Second partition wall, 13...Third partition wall, 14...Fourth partition wall, 11a, 13a...One opening, 11b, 13b...Other opening, 20a, 20b...Duct, 30A, 30B...Warm air circulation path, 31, 32...Partition wall flow path, 36...Inner battery flow path, 60...Battery chamber, 65...One space, 66...Other space, 81-86...Fuel cell surface, 100, 200...Fuel cell system,

Claims

1. The battery compartment is defined by a partition wall, The fuel cell installed in the battery compartment, A duct that communicates with the battery compartment through at least one opening and the other opening provided in the partition wall, It is equipped with a preheater that supplies heated air, A fuel cell system characterized in that at least the battery chamber, one opening and the other opening, and the duct constitute a warm air circulation path for heated air delivered from a preheater.

2. The partition wall includes a first partition wall, a second partition wall, a third partition wall, and a fourth partition wall. The fuel cell system according to claim 1, wherein two or three of the four surfaces of the first to fourth partition walls are in contact with the fuel cell, and the remaining two or one partition wall constitutes a partition wall passage for circulating heated air between itself and the fuel cell, as part of the warm air circulation path.

3. The fuel cell system according to claim 2, wherein the two or three partition walls in contact with the fuel cell are made of a metal member or a high thermal conductivity member.

4. The second to fourth partitions are in contact with the fuel cell, The fuel cell system according to claim 2, wherein the first partition wall is configured to have a first partition wall flow path for circulating heated air between it and the upper surface of the fuel cell, as part of the warm air circulation path.

5. The third and fourth partitions are in contact with each side of the fuel cell, The warm air circulation path is, Between the first partition wall and the upper surface of the fuel cell, there is a first partition wall flow path for flowing heated air, The fuel cell system according to claim 2, further comprising a second partition channel for circulating heated air between the second partition and the bottom surface of the fuel cell.

6. The fuel cell is equipped with a pair of vents for intake and exhaust, The fuel cell system according to claim 1, wherein a pair of vents and the inside of the fuel cell constitute an internal flow path through which heated air passes, as part of a warm air circulation path.

7. The fuel cell system according to claim 1, further comprising an opening / closing device for opening or closing one opening and / or the other opening of a partition wall to connect or block a warm air circulation path.

8. The partition wall includes a fifth partition wall and a sixth partition wall that are opposite to each other. The fifth and sixth partitions each have ventilation openings. The preheater is It is provided in one opening or the other opening of the partition wall, The fuel cell system according to claim 1, provided between a ventilation opening of the fifth or sixth partition and the fuel cell.

9. The battery chamber includes one space between the fifth partition and the fuel cell, and another space between the sixth partition and the fuel cell. The preheater is installed in one of the openings located on the side of the space, The fuel cell system according to claim 8, wherein the outlet of the preheater is located in a space with a smaller volume than the other spaces.

10. The battery chamber includes one space between the fifth partition and the fuel cell, and another space between the sixth partition and the fuel cell. The fuel cell system according to claim 8, wherein the preheater is provided in another space having a smaller volume than one space and is positioned between the ventilation opening of the sixth partition and the fuel cell.

11. The fuel cell system according to claim 8, further comprising a shutter to open or close the ventilation opening of the fifth partition and / or the ventilation opening of the sixth partition.

12. When the fuel cell system described in claim 1 is started, if the measured temperature of the battery chamber is below a first temperature, the preheater is activated and heated air is circulated in the warm air circulation path. A method for operating a fuel cell system, characterized by including the step of circulating heated air in a warm air circulation path, and when a certain period of time has elapsed and / or when the measured temperature in the battery chamber reaches a second temperature or higher, activating the fuel cell and starting power generation.

13. A method for operating a fuel cell system according to claim 12, wherein the process of circulating heated air in a warm air circulation path includes filling at least the upper space between the upper partition wall and the fuel cell, the space between the front partition wall and the fuel cell, and the back space between the back partition wall and the fuel cell with heated air, thereby bringing the heated air into contact with the surface of the fuel cell.

14. A method for circulating heated air in a fuel cell system according to claim 9, characterized in that heated air sent from a preheater provided in one opening of the first partition wall flows through a first warm air circulation path, passing through one space of the battery chamber, the top surface and interior of the fuel cell 1, the other space of the battery chamber, the other opening of the first partition wall, and an upper duct communicating from the first partition wall, before returning to one opening.

15. A method for circulating heated air in a fuel cell system according to claim 10, characterized in that heated air sent from a preheater provided in another space of the battery chamber flows through the other space, the top, bottom and interior of the fuel cell, one space of the battery chamber, one opening of the third partition wall, a side duct communicating from the third partition wall, and the other opening of the third partition wall, and returns to the other space.

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