Vehicle fuel cell apparatus with improved air intake

A vehicle fuel cell apparatus includes a fuel cell stack configured to take in air as a reaction gas and a coolant through an air intake aperture area, and discharge temperature-raised air through air discharging aperture areas. An air suction duct, air discharge ducts, and air discharge fans take in air to the air suction duct. The air discharge ducts have air discharge ports in the vicinity of the air suction duct. The air suction duct is formed with first air intake ports opening at its upstream end portion, and second air intake ports opening at locations nearer to the air discharge ports of the air discharge ducts than the first air intake ports. The second air intake ports are provided with shutters. The arrangement provides a vehicle fuel cell apparatus having enhanced operability in situations involving low-temperature outside air, and allows for enhanced mountability to vehicles.

CROSS REFERENCE TO RELATED APPLICATION

This application is a 35 U.S.C. 371 National Phase Entry Application from PCT/JP2013/061899, filed Apr. 23, 2013, which claims priority to Japanese Patent Application No. 2012-103114, filed Apr. 27, 2012, the disclosures of which are incorporated herein in their entirety by reference.

TECHNICAL FIELD

The present invention relates to a fuel cell apparatus for vehicles, and particularly, to a fuel cell apparatus for vehicles using air as a reaction gas and a coolant.

BACKGROUND ART

As an issue on fuel cell vehicles, there is the problem of undergoing a reduced startability at low temperatures. In cases of fuel cell vehicles parked outdoor in the night, or under low-temperature environments such as those in cold weather districts, fuel cells may have reduced power-generating performances, involving such cases as failing to feed necessary power when starting or running. In this regard, as a countermeasure, there has been proposed a method of warming a fuel cell stack, using a heater or an exhaust fan (for instance, refer to the patent literature 1 below). This method involves issues including increased power consumed by the heater, or increased numbers of parts such as those due to addition of the exhaust fan to be dedicated for the warming. Moreover, there has been proposed a method of using discharge gases of fuel cells for heating pieces of equipment to be warmed (for instance, refer to the patent literature 2 below). Besides them, there have been proposed warming methods using heat storage materials or catalyst combustion, or the like. However, all the proposals have been accompanied by problems such as complexity of the system being a fuel cell apparatus, and an increased number of components being the parts.

TECHNICAL LITERATURES

Patent Literatures

Patent Literature 1:

Japanese Patent Application Laying Open Publication No. 2010-234992

Patent Literature 2:

Japanese Patent Application Laying Open Publication No. 2009-140872

SUMMARY OF INVENTION

Problem to be Solved by the Invention

For this reason, the present invention has been devised in view of problems described, and it is an object thereof to provide a fuel cell apparatus for vehicles adapted for a fuel cell stack to have enhanced operability in situations involving low-temperature outside air, allowing for enhanced mountability to vehicles.

Solution to the Problem

According to aspects of the present invention, there is a fuel cell apparatus for vehicles including a fuel cell stack disposed in a space enclosed by vehicle body panels, and configured to take in air as a reaction gas and a coolant through an air intake aperture area to an inside thereof, and discharge temperature-raised air through an air discharging aperture area to an outside thereof, an air suction duct connected to the air intake aperture area, an air discharge duct connected to the air discharging aperture area, and a fan configured to take in air to the air suction duct, characterized by the air discharge duct having an air discharge port thereof disposed in a vicinity of the air suction duct, the air suction duct being formed with a first air intake port set opening at an upstream end portion of the air suction duct, and a second air intake port set opening at a location set nearer to the air discharge port than the first air intake port set, and a shutter set provided at the second air intake port set to open or close the second air intake port set.

An aspect described is characterized in that the shutter set is set up to open when outside air has temperatures lower than a lower limit temperature of a range of temperatures affording for the fuel cell stack to operate as necessary.

An aspect described is characterized in that the fuel cell stack is mounted on a vehicle, with the air intake aperture area in a vehicle-longitudinally frontward oriented position, and the second air intake port set is substantially vehicle-longitudinally rearward open.

An aspect described is characterized in that the second air intake port set is arranged on both vehicle-transverse sides of the air suction duct.

An aspect described is characterized in that the first air intake port set is provided with a shutter set to open or close the first air intake port set.

Effects of the Invention

According to the present invention, it is possible to implement a fuel cell apparatus for vehicles adapted for a fuel cell stack to have enhanced operability in situations involving low-temperature outside air, allowing for enhanced mountability to vehicles.

EMBODIMENTS FOR CARRYING OUT THE INVENTION

There will be described details of a fuel cell apparatus for vehicles according to an embodiment of the present invention, with reference to the drawings. This embodiment employs senses of longitudinal, transverse, and vertical directions of a vehicle defined by arrows in drawings, for the convenience in description.

As shown inFIG. 1andFIG. 2, at a front section of a vehicle100, there is mounted a fuel cell apparatus1for vehicles. The fuel cell apparatus1for vehicles is disposed in an engine room104that is a space enclosed by vehicle body panels at the front section of the vehicle100. As shown inFIG. 1andFIG. 2, the vehicle body panels include an engine hood101, side panels102, and a dash panel103. The engine room104is furnished with a drive motor105, an inverter106, and a radiator107, besides the fuel cell apparatus1for vehicles. The fuel cell apparatus1for vehicles is substantially made up by an air suction duct2, a pair of fuel cell stacks3, two pairs of air discharge ducts4provided as one pair and one pair on the fuel cell stacks3, respectively, and air discharge fans5provided on the air discharge ducts4in a one-to-one relationship.

As shown inFIG. 3, the air suction duct2includes a first duct portion210, a second duct portion220, and a third duct portion230. The first duct portion210has a box structure outlined substantially in a cuboid shape. At a vehicle-longitudinally front side of the first duct portion210there is a front panel211formed with a pair of first air intake ports212. These first air intake ports212are formed at vertically spaced two locations on the front panel211. The first air intake ports212have their shutters213. The shutters213are adapted to be driven to rotate with a shutter driver213A, to thereby open or close the first air intake ports212.

As shown inFIG. 7, the first duct portion210has a rear side panel214opposed to the front side panel211and formed with an opening214A. This opening214A is contoured to be slightly smaller than a contour of the rear side panel214. In other words, the opening214A has an area occupying the rear side panel214, in a proportion set to be large. The second duct portion220is made as a tubular body rectangular in sections perpendicular to the axial direction. The second duct portion220has, at sections perpendicular to the axial direction, contours thereof set to be larger than the opening214A formed in the rear side panel214. The second duct portion220is connected to the rear side panel214of the first duct portion210, to have air communication with the opening214A formed in the rear side panel214. Moreover, as shown inFIG. 4, the second duct portion220has a rectangular planar filter221accommodated therein. It is noted that the second duct portion220has an axial length thereof set to be nearly equal to the thickness of the filter221, and relatively short.

As shown inFIG. 4, the third duct portion230is made in the form of an inside-hollow box outlined substantially in a trapezoidal prismatic shape. As shown inFIG. 7, the third duct portion230has a front side panel231disposed at the vehicle-longitudinally front side, and a pair of lateral side panels232disposed on both sides in the vehicle-transverse direction. It is noted that the third duct portion230has a pair of downstream openings235in a vehicle-longitudinally rear part thereof. It also is noted that those downstream openings235have their aperture areas235A disposed to be substantially perpendicular to each other. At the third duct portion230, one of the downstream openings235has a center axis thereof upwardly diagonally vehicle-longitudinally rearward oriented. At the third duct portion230, the other of the downstream openings235has a center axis thereof downwardly diagonally vehicle-longitudinally rearward oriented. There is an upstream opening231A formed in the front side panel231. And, the front side panel231is connected to a downstream end of the second duct portion220, to have air communication with the second duct portion220.

As shown inFIG. 5andFIG. 6, the lateral side panels232have second air intake ports232A formed therein. The second air intake ports232A are formed along the vehicle-vertical direction. At the outsides of the second air intake ports232A, there are provided hood parts232B opening rearward to take in discharged air from vehicle-longitudinally rear sides. That is, the second air intake ports232A are implemented by provision of the hood parts232B to open substantially vehicle-longitudinally rearward. Moreover, the hood parts232B have shutters232C accommodated therein to open or close the second air intake ports232A. As shown inFIG. 7, the shutters232C are to be driven by shutter drivers232D to serve for open-close operations. The shutter drivers232D are provided on the interior sides of the lateral side panels232. It is noted that the shutters232C are set up to open when outside air has temperatures lower than a prescribed temperature (as a lower limit temperature of a range of temperatures affording for the fuel cell stacks3to operate as necessary).

The fuel cell stacks3have a configuration including unshown electrolyte films, hydrogen electrodes, air electrodes, and separators multi-layered to stack up. As shown inFIG. 7, the fuel cell stacks3each have an air intake aperture area31constituting one side of a rectangular parallelepiped structure, and an air discharging aperture area32constituting the other side in parallel with the air intake aperture area31. At the fuel cell stacks3, air is used as a reaction gas and a coolant. Moreover, as shown inFIG. 4andFIG. 7, the fuel cell stacks3each have filter holders33formed in a short rectangular duct shape, and provided at the side of the air intake aperture area31. The filter holders33have rectangular planar filters34accommodated therein. As shown inFIG. 7, each fuel cell stack3is connected, at the air intake aperture area31side, to a downstream opening235of the third duct portion230, to have air communication therewith.

FIG. 8is a block diagram of the fuel cell apparatus1for vehicles according to this embodiment. As shown inFIG. 8, there is arrangement including a hydrogen tank6having high-pressure compressed hydrogen gas stored therein, which is pressure-reduced at a pressure reducing valve9, to introduce to unshown anode air-suction parts of the fuel cell stacks3. On the other hand, outside air suctioned into the air suction duct2is driven forth by the air discharge fans5, employing no high-pressure compressing compressor, to supply through the filters221and34to unshown cathode air-suction parts of the fuel cell stacks3. At the fuel cell stacks3, supplied air is not simply used for reactions to generate electricity, but also for services to cool the fuel cell stacks3. There is an unshown anode air discharge line connected through a purge valve8to an unshown cathode air discharge line, and is adapted to serve, when surplus hydrogen gases are discharged at the anode side to discharge outside the vehicle, for use of air discharged at the cathode side to dilute hydrogen gases below a lower limit of inflammable concentration, to release into atmosphere. Further, as shown inFIG. 7, the fuel cell stacks3are adapted to take air inside through the air intake aperture areas31, and discharge temperature-raised air outside through air discharging aperture areas32.

As shown inFIG. 3throughFIG. 6, at each fuel cell stack3, paired air discharge ducts4fixed thereto are arranged to neighbor each other in the vehicle-transverse direction. As shown inFIG. 7, each air discharge duct4as a rectangular-prismatic tubular duct is connected to the air discharging aperture area32side of the fuel cell stack3, to have air communication therewith. And, each air discharge duct4has an air discharge fan cover41of a circle-tubular shape fixed thereto at the downstream end. As shown inFIG. 5andFIG. 6, the air discharge fan cover41has an air discharge fan5installed therein. It is noted that, in this embodiment, the air discharge fan cover41has an air discharge port42disposed in a vicinity of the air suction duct2. In other words, the air discharge port42is located at short distances from a second air intake port232A, for connection thereto.

(Operations and Effects of Fuel Cell Apparatus for Vehicles)

Description is now made of operations and effects of the fuel cell apparatus1for vehicles according to this embodiment. First, upon a startup of the fuel cell apparatus1, hydrogen gas and air are introduced to the fuel cell apparatus1. More specifically, as shown inFIG. 8, high-pressure compressed hydrogen gas stored in the hydrogen tank6is pressure-reduced by the pressure reducing valve7, to introduce into unshown anode air suction parts of the fuel cell stacks3adapted therefor. On the other hand, outside air is suctioned into the air suction duct2through the filter221, and supplied by use of the air discharge fans5to the unshown anode air suction parts of the fuel cell stacks3, which have no high-pressure compression compressor. It is noted that, at the fuel cell stacks3, such supplied air is not simply used for reactions to generate electricity, but also for services to cool the fuel cell stacks3. Surplus hydrogen gases discharged at the anode side are diluted, by use of air discharged at the cathode side, below a lower limit of inflammable concentration to release into atmosphere, when discharging outside the vehicle. And, there is adaptation for discharge air discharged from the fuel cell stacks3to be conducted through the air discharge ducts4, to release rearward in the engine room104. Therefore, discharge air discharged from the air discharge ducts4is effective for the inside of the engine room104ttoewarmed.

Under a prescribed low-temperature environment, the shutter driver213A is operated to close the shutters213at the first air intake ports212. Concurrently with the operation of the shutter driver213A, the shutter drivers232D are operated for operations of the shutters232C to open the second air intake ports232A. Here, the prescribed low-temperature environment refers to a situation in which the outside air temperature is lower than a lower limit temperature in an adequate range of temperatures for the fuel cell stacks3to operate as needed.

In this situation, the air discharge fans5are driven to rotate, and hence as shown inFIG. 6, air A5 (represented by arrows inFIG. 6) warmed along with startup of the fuel cell apparatus1comes around from the air discharge ports42to the second air intake ports232A, where it is introduced into the air suction duct2. Thus introduced warm air A4R (represented by arrows inFIG. 6) in the air suction duct2is taken in through the air intake aperture areas31of the fuel cell stacks3, to insides of the fuel cell stacks3, where it serves for reactions to generate electricity, and early warm-up of the fuel cell stacks3.

On the other hand, the shutter drivers232D are operable to close the shutters232C provided at the second air intake ports232A, in situations needing no warm-up of the fuel cell stacks3, that is, when having got higher than the lower limit of the range of adequate temperatures for the fuel cell stacks3to operate as needed. Such being the case, the second air intake ports232A located near the air discharge ports42of the air discharge ducts4can be closed, to thereby prevent warm air from the air discharge ports42from being introduced into the air suction duct2. In this situation, the first air intake ports212are open. It is noted that the hood parts232B provided at the second air intake ports232A are vehicle-longitudinally rearward open, whereby air streams when running, vicinal to the air suction duct2, have reduced tendencies to directly inflow.

As shown inFIG. 7, in situations in which only the first air intake ports212are open, air A1 (represented by arrows inFIG. 7) under suctioning effects by air discharge fans5, or when running, is introduced through the first air intake ports212into the first duct portion210. Air A2 (represented by arrows inFIG. 7) introduced into the first duct portion210is introduced through the filter221at the second duct portion220into the third duct portion230. Air A4 introduced into the third duct portion230is divided at the paired downstream openings235, into two to be introduced inside the fuel cell stacks3. Warmed air having passed the fuel cell stacks3passes the air discharge ducts4, constituting air A5 (represented by arrows inFIG. 7) to be discharged from the air discharge ports42.

As described, according to an embodiment of the invention, there is a fuel cell apparatus1for vehicles including a fuel cell stack3disposed in a space (as an engine room104) enclosed by vehicle body panels involving an engine hood101, side panels101, and a dash panel103, and configured to take in air as a reaction gas and a coolant through an air intake aperture area31to the inside, and discharge temperature-raised air through an air discharging aperture area32to the outside, an air suction duct2connected to the air intake aperture area31, an air discharge duct4connected to the air discharging aperture area32, and an air discharge fan5configured to take in air to the air suction duct4, characterized in that the air discharge duct4has an air discharge port42thereof disposed in a vicinity of the air suction duct2, the air suction duct2is formed with a set of first air intake ports212opening at an upstream end portion of the air suction duct2, and a set of second air intake ports232A opening at a set of locations nearer to the air discharge port42of the air suction duct4than the first air intake port set212, and a set of shutters232C is provided at the second air intake port set232A to open or close the second air intake port set232A.

According to this embodiment, it is possible to implement a fuel cell apparatus1for vehicles adapted for a fuel cell stack3to have enhanced operability in situations involving low-temperature outside air, allowing for enhanced mountability to a vehicle100. Such being the case, the fuel cell apparatus1for vehicles according to this embodiment makes use of discharge air of the fuel cell stack3for warm-up, thereby avoiding the need of separate provision such as that of a heat source such as a heater, or a heat source making use of a heat producing reaction of a catalyst reaction. Moreover, the fuel cell apparatus1for vehicles according to this embodiment does not need a dedicate coolant line to be used for war-up, either. Such being the case, the fuel cell apparatus1for vehicles according to this embodiment allows for suppressed power consumption to be minimized as necessary. Further, the fuel cell apparatus1for vehicles according to this embodiment can solve problems such as increases in numbers of component parts, or complexity of the system.

The fuel cell apparatus1for vehicles according to this embodiment configured as described is operable in situations involving low-temperature outside air, to open the shutter set232C provided at the second air intake port set232A, permitting air (as discharge air) heated at the fuel cell stack3and released outside from the air discharge port42to be introduced into the air suction duct2, thereby allowing for the fuel cell stack3to have temperatures raised to be optimal for operation. Moreover, this embodiment can control a proportion between amounts of air introduced to the first air intake port set212and the second air intake port set232A, thereby allowing for a temperature condition of the fuel cell stack3to be always kept adequate.

The fuel cell apparatus1for vehicles according to this embodiment has the air suction duct2provided with the second air intake port set232A, thereby permitting high-temperature discharge air to be introduced at the location set near the air discharge port42, allowing for the fuel cell stack3to have temperatures raised to be optimal for operation within a shorter interval of time.

The fuel cell apparatus1for vehicles according to this embodiment permits discharge air (as air) released inside the engine room104to be suctioned straightly from the air discharge duct4into the air suction duct2, without extending the air discharge duct4up to a vicinity of the air suction duct2. Therefore, this fuel cell apparatus1for vehicles can reduce fluid resistances when suctioning air through the second air intake port set232A, while implementing a simplified configuration allowing for enhanced mountability to the vehicle100.

In the fuel cell apparatus1for vehicles according to this embodiment, hood parts232B provided at second air intake ports232A are provided to face vehicle-longitudinally rearward. Therefore, the fuel cell apparatus1for vehicles can prevent air streams when running from flowing into the second air intake ports232A. This allows for the fuel cell stack3to have temperatures raised to be optimal for operation within a shorter interval of time. Moreover, the second air intake ports232A are provided in lateral side panels232at both vehicle-transverse sides of a third duct portion230, thereby permitting the second air intake ports232A at both sides of the third duct portion230to take in air released from the fuel cell stack3to the periphery. Therefore, warmed air can be efficiently introduced through the second air intake ports232A at both sides, allowing for the fuel cell stack3to have temperatures raised to be optimal for operation within a shorter interval of time.

Further, the fuel cell apparatus1for vehicles according to this embodiment is operable in situations involving low-temperature outside air, to close a set of shutters213provided at the first air intake port set212, thereby increasing amounts of air introduced through the second air intake port set232A into the fuel cell stack3, allowing for the fuel cell stack3to have temperatures raised earlier to be optimal for operation.

This embodiment is characterized in that the shutter set232C is set up to open when outside air has temperatures lower than a lower limit temperature of a range of temperatures affording for the fuel cell stack3to operate as necessary. Therefore, according to this embodiment, it is possible to introduce warm air in the engine room104when outside air has temperatures lower than the lower limit temperature of the range of temperatures affording for the fuel cell stack3to operate as necessary, thus allowing for the fuel cell stack3to operate as needed.

This embodiment is characterized in that the fuel cell stack is mounted on the vehicle, with the air intake aperture area31in a vehicle-longitudinally frontward oriented position, and the second air intake port set232A is substantially vehicle-longitudinally rearward open. Therefore, according to this embodiment, it is possible to prevent air streams when running from entering the second air intake port set232A when the vehicle100is running, allowing for the fuel cell stack3to have temperatures raised to be optimal for operation within a shorter interval of time.

This embodiment is characterized in that the second air intake port set is arranged on both vehicle-transverse sides of the air suction duct. This embodiment permits the second air intake ports232A disposed at both vehicle-transverse sides of the air suction duct2to take in air released from the fuel cell stack3to peripheral spaces, allowing for the fuel cell stack3to have temperatures raised to be optimal for operation within a shorter interval of time.

This embodiment is characterized in that the first air intake port set212is provided with the shutter set213to open or close the first air intake port set212. According to this embodiment, it is possible in situations involving low-temperature outside air, to close the shutter set213provided at the first air intake port set212, thereby increasing amounts of air suctioned through the second air intake port set232A into the fuel cell stack3, allowing for the fuel cell stack3to have temperatures raised earlier to be optimal for operation.

Other Embodiments

Embodiments have been described, including discussions and drawings constituting part of the disclosure, which should not be construed as restrictive to the invention. There may be various substitute embodiments, examples, and application techniques made apparent to artisan from the disclosure.

For instance, in the embodiment described, discharge air released from the air discharge port42is introduced to the second air intake port set232A via a space in the engine room104, while there may be employed a configuration including a transfer path such as a hose for conducting discharge air from the air discharge port42to a vicinal position. It is noted that, in the embodiment described, the second air intake ports232A are formed in an elongate shape in the lateral side panels232at both sides, respectively, while the second air intake ports232A may have their locations for installation, shapes, or piece numbers changed as necessary, as a matter of course.

Moreover, the embodiment described has the air discharge fans5disposed downstream of the fuel cell stacks3, which may well be substituted with a configuration including air discharge fans5disposed upstream of fuel cell stacks3. Still more, the embodiment described has the paired downstream openings235provided downstream of the air suction duct2, while the number of downstream openings235is variable as necessary. Yet more, the embodiment described includes the air suction duct2and the air discharge ducts4, of which structures also are not restrictive to this invention.

Further, the embodiment described includes the downstream openings235having their aperture areas235arranged to make right angles with each other, while they are not limited to right angles.

DESCRIPTION OF REFERENCE SIGNS