DE102016113740A1 - Conditioning module for a working medium of a fuel cell stack and fuel cell system and vehicle with this conditioning module - Google Patents

Abstract

The invention relates to a conditioning module (40) for an operating medium, in particular an anode operating medium or cathode operating medium, of a fuel cell stack (10). The conditioning module (40) is a combination of heat exchangers, in particular radiator, and humidifier with very little space requirement with high possible throughput. For this purpose, the heat exchanger is arranged in a first volume (42) and the humidifier in a second volume (43), wherein these volumes (42, 43) are spatially in one another. In other words, in a cross-section of the conditioning module (40), a first cross-sectional area (45) of one of the first and second volumes is disposed within a second cross-sectional area (46) of the other of the first and second volumes. Preferably, the first (42) and second volumes (43) are concentric cylinders.

Description

The invention relates to a conditioning module for an operating medium, in particular for the cathode operating medium, a fuel cell stack and a fuel cell system with such a conditioning module. Furthermore, the invention relates to a vehicle with such a conditioning module or such a fuel cell system.

Fuel cells use the chemical conversion of a fuel with oxygen to water to generate electrical energy. For this purpose, fuel cells as a core component to a membrane-electrode assembly (MEA - membrane electrode assembly) on. This is formed by a proton-conducting membrane, on both sides of which catalytic electrodes are arranged. In this case, the membrane separates the anode chamber associated with the anode and the cathode chamber associated with the cathode gas-tight from each other and electrically isolated. In addition, gas diffusion layers can be arranged on the non-membrane-facing sides of the electrodes.

During operation of the fuel cell, a hydrogen-containing fuel is supplied to the anode, at which an electrochemical oxidation of H ₂ to H ⁺ takes place with release of electrons. Via the electrolytic membrane, a water-bound or water-free transport of the protons H ⁺ from the anode space into the cathode space takes place. The electrons provided at the anode are supplied to the cathode via an electrical line. The cathode is supplied with an oxygen-containing operating medium, so that there is a reduction of O ₂ to O ₂ ^- taking the electrons. These oxygen anions react in the cathode compartment with the protons transported across the membrane to form water. The direct conversion of chemical into electrical energy is not limited by the Carnot factor and therefore has improved efficiency over other heat engines.

As a rule, a fuel cell is formed by a multiplicity of MEAs arranged in a fuel cell stack (stack), the electrical powers of which accumulate. Bipolar plates are usually arranged between the membrane-electrode assemblies, which ensure a supply of the individual MEA with the reactants and a cooling liquid and act as an electrically conductive contact to the membrane-electrode assemblies. At both ends of the fuel cell stack, end plates or monopolar plates are arranged to hold it together and compress the stack components. The pressing pressure contributes to the sealing of the stack and ensures adequate electrical contact between the stack components.

The cathode electrodes are supplied via a cathode field open flow field of the bipolar plates, a so-called cathode operating medium, in particular oxygen (O ₂ ) or an oxygen-containing gas mixture, for example air, so that a reduction of O ₂ to O ^2- takes place under a recording of electrons (1 / 2O ₂ + 2e ^- → O ^2- ). At the same time, oxygen anions (O ^2- ) formed on the cathode electrodes react with the protons transported through the membranes or electrolytes to form water (2H ⁺ + O ^2- > H ₂ O).

In order to supply a fuel cell stack with the operating media, this has on the one hand an anode supply and on the other hand, a cathode supply. The anode supply includes an anode supply path for supplying the anode operating medium into the anode chambers of the fuel cell and an anode exhaust gas path for discharging an anode exhaust gas out of the anode chambers. Similarly, the cathode supply includes a cathode supply path for supplying the cathode operating medium into the cathode chambers of the fuel cell and a cathode exhaust path for discharging a cathode exhaust gas out of the cathode compartments.

The fuel cell system includes a humidifier for humidifying a dry cathode operation medium (supply air) by which moisture is transferred from the cathode exhaust gas (exhaust air) to the cathode operation medium. The moistening is necessary to ensure a high power density and lifetime of the fuel cell, in particular its membrane-electrode assembly. Further, the dry cathode operating medium is compressed to a pressure of about 3 bar to increase the power density upstream of the humidifier. As a result, its temperature rises to about 200 ° C.

The polymer membranes used in conventional humidification humidifiers can only be used up to a temperature of about 100.degree. Therefore, the cathode operating medium must be cooled before it is fed to the humidifier. For this purpose, intercoolers are usually used, which absorb heat from the cathode operating medium by means of a coolant and deliver it to the environment via a cooler. This results in a high space requirement, which is particularly disadvantageous for mobile applications.

Attempts have therefore already been made to optimize the arrangement of humidifier and intercooler or both components in a integrate common housing. So far, however, only small savings in space could be achieved while significantly increased complexity of the combined components. The combined components also have high thermal mass, which adversely affects the dynamics of the fuel cell system.

The invention is based on the object to provide a combined humidifier and intercooler for a fuel cell system to ensure adequate humidification and cooling of an operating medium of a fuel cell stack. At the same time, the space requirement, the complexity and the manufacturing costs of the combined component should be as low as possible.

This object is achieved by a conditioning module, a fuel cell system and a vehicle having the features of the independent claims. Advantageous developments of the invention are the subject of the respective dependent claims.

The object according to the invention is achieved by a conditioning module for an operating medium of a fuel cell stack with a gas inlet for the operating medium and a flow-through, designed as a heat exchanger and arranged downstream of the gas inlet first volume. Downstream of the first volume, that is to say downstream in the direction of flow of the operating medium, a flow-through volume designed as a humidifier is arranged. Downstream of the second volume, a gas outlet for the conditioned operating medium is provided. In a cross section of the conditioning module, a first cross-sectional area, that is, a cross-sectional area of the first volume or the second volume, is disposed within a second cross-sectional area, that is within the cross-sectional area of the other volume, of the first volume and the second volume. Preferably, the first cross-sectional area is arranged completely within the second cross-sectional area. The operating medium is in particular an anode operating medium or a cathode operating medium.

In other words, the conditioning module according to the invention is a combination of heat exchanger and humidifier, one of these two components being arranged spatially within the other component. The components are arranged such that an operating medium introduced into the conditioning module always first flows through the first volume designed as a heat exchanger before it reaches the second volume designed as a humidifier. In a common cross-section of the conditioning module, one of the first and second volumes has a first cross-sectional area and the other has a second cross-sectional area. In other words, the cross-sectional area of the inner volume, for example of the first volume, in the cross section of the conditioning module is surrounded on all sides by the cross-sectional area of the outer volume, for example of the second volume. Thus, a particularly compact design and a particularly low thermal mass of the conditioning module can be realized. The circumference of the second cross-sectional area may be identical to a surface, for example a housing surface, of the conditioning module. Alternatively, the first and second volumes are arranged in a separate housing of the conditioning module.

The conditioning module according to the invention is advantageously modular. For example, the internal volume, for example, the second volume, in a corresponding opening of the outer volume, for example, the first volume, are inserted. The conditioning module according to the invention is therefore particularly easy to manufacture. Furthermore, a conditioning module according to the invention with a certain total volume has a particularly large interface between the first and the second volume, that is to say between the heat exchanger and the humidifier. The conditioning module can therefore be designed for a high throughput of operating medium even with a small size.

The first volume of the conditioning module is preferably formed as a heat exchanger by having at least one, more preferably a plurality of heat transfer surfaces arranged therein. This is preferably a heat transfer from the operating medium to another medium. The second volume is preferably designed as a humidifier in that it has at least one, preferably a plurality of moisture transfer surfaces arranged therein. About this moisture, especially water, introduced into the operating medium. Between the first and second volumes, one or more boundary surfaces may be arranged, which are permeable to the operating medium, for example by having one or more passage openings for the operating medium. Alternatively, first and second volumes merge without a physical interface.

The arranged in the first volume heat transfer elements are preferably designed to be traversed by a coolant and for this purpose have in particular a coolant inlet and a coolant outlet. Form the surfaces of the heat exchanger elements facing the first volume Heat transfer surfaces over which heat transfers from the operating medium to the coolant. The heat exchanger elements are particularly preferably tubes of a tube bundle heat exchanger or plates of a plate heat exchanger. A conditioning module according to this embodiment can be easily integrated into existing coolant circuits of the fuel cell system or a vehicle by connecting the coolant inlet and outlet to an existing coolant circuit.

The humidifier elements arranged in the second volume are preferably designed to carry water or steam, that is to say to conduct a fluid which contains water or steam. The humidifier elements are connected at least to a fluid inlet, via which the humidifier elements are supplied with the fluid containing water or water vapor. Particularly preferably, the humidifier elements are also connected to a fluid outlet, via which the water or water vapor-containing fluid is removed after the moisture transfer to the operating medium from the second volume. The surfaces of the humidifier elements facing the second volume preferably form moisture transfer surfaces via which moisture is introduced into the operating medium.

The humidifier elements are particularly preferably water-permeable and / or water-vapor-permeable membranes, in particular in the form of hollow-fiber membranes. The second volume is thus preferred as Hohlfaserbefeuchter, as from US 7624971 B2 known, trained. The boundary surface between the first and second volumes or passage openings in a boundary surface separating these volumes form the supply line for the operating medium to be humidified. The gas outlet of the conditioning module forms the outlet for the humidified operating medium. In principle, other moistening elements can also be used, for example, spray nozzles arranged in the second volume, drip lines or wick elements connected to a moisture reservoir with capillary action.

In a further preferred embodiment of the conditioning module according to the invention, this has a cylindrical shape, particularly preferably an elongated cylindrical shape. For the purposes of this application, a cylindrical shape is understood to be a body which is obtained by shifting a plane closed curve along a straight line (height) not contained in the plane of this curve. The plane curve may describe the circumference of a circle, an ellipse, a rectangle, a square, a triangle, a polygon, a prism and / or a trapezoid. This shape then forms the base of the cylindrical shape. The swept over by moving the base surface area is the lateral surface of the cylindrical shape. Particularly preferred are also the first volume and the second volume cylinder volume. Advantageously, such a conditioned conditioning module is easy to manufacture and can be easily integrated into existing space distributions. In addition, with a short flow path of the operating medium from the gas inlet to the gas outlet, a comparatively large contact surface with the humidifier elements and / or heat exchanger elements can be realized.

Particularly preferably, the first cross-sectional area and the second cross-sectional area of the conditioning module are concentric with each other. A cross-sectional area of a housing of the conditioning module is preferably identical or likewise concentric to the second cross-sectional area. The concentricity of the first and second cross-sectional area advantageously permits even cooling and humidifying of the working medium in the entire volume of the conditioning module. Further preferably, the gas inlet or gas outlet is located at or near a midpoint of one of the concentric cross-sectional areas, which also contributes to uniform humidification and cooling of the operating medium.

Furthermore, the conditioning module preferably has a third volume, which is designed as a gas distributor and is arranged upstream of the first volume. In a cross-section of the conditioning module, a third cross-sectional area of the third volume is disposed within the first cross-sectional area and within the second cross-sectional area. The conditioning module thus has an internal volume without heat exchanger or humidifier elements arranged therein for distributing the operating medium over the entire height of a, in particular cylindrical, conditioning module. Particularly preferably, the gas distributor is formed as an internal cylinder volume which is separated by a lateral surface from the first volume arranged downstream, the lateral surface having a multiplicity of openings and preferably a cross-sectional area concentric with the first and second cross-sectional areas. Preferably, the openings in the flow direction of the operating medium increase in order to compensate for a pressure drop.

Alternatively preferably, the third volume is designed as a gas collector, arranged downstream of the second volume and designed to collect the conditioned operating medium exiting from the second volume and to forward it to the gas outlet. Preferably, the gas inlet of the conditioning module is in the range the gas distributor or the gas outlet of the conditioning module arranged in the region of the gas collector.

The conditioning module according to the invention also preferably has a plurality of gas inlets or gas outlets arranged on a surface of the conditioning module. Again, the regularity of cooling and humidifying the operating medium and its throughput can be increased by the conditioning module. In particular, in combination with a corresponding, arranged at or near a center of the concentric first and second cross-sectional area gas inlet or gas outlet can be adjusted on all sides uniform flow of the operating medium.

Particularly preferably, the first volume and the second volume of the conditioning module according to the invention are formed by concentric circular cylinders. In this embodiment, as a tubular conditioning module, an optimum ratio of surface area and volume of the module and thus a particularly small space requirement is achieved. A gas inlet or outlet is located in this embodiment near or at the midpoint of a face or face of the concentric cylinders. The corresponding gas outlet or gas inlet is arranged on the lateral surface of the preferably also circular-cylindrical conditioning module, which is identical or concentric to the lateral surface of the outer volume. Preferably, in this embodiment, the conditioning module has a third volume formed by a circular cylinder concentric with the first and second volumes. For example, by the combination of a third volume designed as a gas distributor, as described above, and a plurality of gas outlets arranged on the outer surface of the outer volume, a particularly uniform flow in all the radial directions of the conditioning module can be achieved. The circular first and second cross-sectional area of the tubular conditioning module also allow an entire area uniform and thus optimal packing density of circular cylindrical hollow fibers or tubular heat exchanger elements. The volume of the conditioning module is used optimally.

The invention likewise provides a fuel cell system with a fuel cell stack, comprising an anode supply with an anode supply path and an anode exhaust gas path and a cathode supply with a cathode supply path and a cathode exhaust gas path and at least one conditioning module arranged in the anode supply or the cathode supply, as described above. In a preferred embodiment of the fuel cell system according to the invention, the conditioning module is arranged in the cathode supply and has a gas inlet for a cathode operating medium and a gas outlet for the conditioned cathode operating medium.

In a further preferred embodiment of the fuel cell system, the conditioning module has heat transfer elements arranged in the first volume, which are connected fluid-carryingly with a coolant inlet for a cathode exhaust gas. In other words, the coolant inlet is connected to the cathode exhaust gas line of the fuel cell system, so that the heat transferring elements are flowed through by the cathode exhaust gas as coolant. The heat exchanger elements are preferably heat exchanger plates or heat exchanger tubes. Also preferably, the conditioning module comprises in the second volume arranged humidifier elements, which are fluidly connected to a fluid inlet for the cathode exhaust gas. In other words, the humidifier elements are flowed through by the cathode exhaust gas as a water or water vapor laden fluid and moisture supplier. The humidifier elements are preferably hollow-fiber membranes of a hollow-fiber humidifier. In this embodiment, the conditioning module is particularly easy to integrate into existing fuel cell systems, the cathode exhaust gas of the fuel cell stack is advantageously used in spatially separate areas, first for cooling and then for humidifying the operating medium.

Likewise provided by the invention is a vehicle having a conditioning module as described above or with a fuel cell system as described above.

Further preferred embodiments of the invention will become apparent from the remaining, mentioned in the dependent claims characteristics.

The various embodiments of the invention mentioned in this application are, unless otherwise stated in the individual case, advantageously combinable with each other.

The invention will be explained below in embodiments with reference to the accompanying drawings. Show it:

1 a block diagram of a fuel cell system according to a preferred embodiment;

2 a schematic representation of a conditioning module according to a first embodiment;

3 a schematic representation of a conditioning module according to a second embodiment;

4 a schematic representation of a conditioning module according to a third embodiment; and

5 a schematic representation of a conditioning module according to a fourth embodiment.

1 shows a schematic representation of a total with 100 designated fuel cell system according to the prior art. This is part of an electric or hybrid vehicle, not shown, having an electric traction motor driven by the fuel cell system 100 is supplied with electrical energy.

The fuel cell system 100 comprises as a core component a fuel cell stack 10 containing a plurality of stacked single cells 11 having alternately stacked membrane-electrode assemblies (MEAs) 14 and bipolar plates 15 be formed (see detail). Every single cell 11 thus includes one MEA each 14 , which has an ion-conducting polymer electrolyte membrane, not shown here, as well as on both sides arranged thereon catalytic electrodes, namely an anode and a cathode, which catalyze the respective partial reaction of the fuel cell reaction and in particular can be formed as coatings on the membrane.

The anode and cathode electrodes comprise a catalytic material, such as platinum, supported on an electrically conductive high surface area support material, such as a carbon based material. Between a bipolar plate 15 and the anode thus becomes an anode compartment 12 formed and between the cathode and the next bipolar plate 15 the cathode compartment 13 , The bipolar plates 15 serve to supply the operating media in the anode and cathode rooms 12 . 13 and further provide the electrical connection between the individual fuel cells 11 ago. Optionally, gas diffusion layers are between the MEAs 14 and the bipolar plates 15 arranged.

To the fuel cell stack 10 to supply the operating media, have the fuel cell systems 100 on the one hand, an anode supply 20 and on the other hand, a cathode supply 30 on.

The anode supply 20 of in 1 shown fuel cell system 100 includes an anode supply path 21 which feeds an anode operating medium (the fuel), for example hydrogen, into the anode spaces 12 of the fuel cell stack 10 serves. For this purpose, connect the anode supply paths 21 a fuel storage 23 with an anode inlet of the fuel cell stack 10 , The anode supply 20 further includes an anode exhaust path 22 containing the anode exhaust gas from the anode chambers 12 via an anode outlet of the fuel cell stack 10 dissipates.

The anode operating pressure on the anode sides 12 of the fuel cell stack 10 is about a first actuating means 24 in the anode supply path 21 adjustable. In addition, the anode supply points 20 of in 1 shown fuel cell system as shown, a recirculation line 25 on which the anode exhaust path 22 with the anode supply path 21 combines. The recirculation of fuel is common in order to return and utilize the fuel, which is mostly used in excess of stoichiometry, in the stack. In the recirculation line is a recirculation conveyor 27 , preferably a recirculation blower, arranged. Further, in the anode exhaust path 22 downstream of the fuel cell stack 10 a water separator 28 Installed inside the recirculation circuit to get out of the fuel cell stack 10 discharge discharged liquid water.

In the anode exhaust gas line 22 of in 1 shown fuel cell system 100 is downstream of the recirculation line 25 a second actuating means 26 arranged. With the second actuating means 26 a recirculation circuit can be isolated from the environment. The first and second actuating means 24 . 26 can be used in common, an outflow of the anode operating medium from the anode chambers 12 largely to prevent.

The cathode supply 30 of in 1 shown fuel cell system 100 includes a cathode supply path 31 which is the cathode spaces 13 of the fuel cell stack 10 supplying an oxygen-containing cathode operating medium, in particular air which is drawn in from the environment. The cathode supply 30 further includes a cathode exhaust path 32 , which the cathode exhaust gas (in particular the exhaust air) from the cathode compartments 13 of the fuel cell stack 10 dissipates and optionally this feeds an exhaust system, not shown. For the promotion and compression of the cathode operating medium is in the Cathode supply path 31 a compressor 33 arranged.

In the illustrated embodiments, the compressor 33 as a mainly electric motor driven compressor 33 designed, the drive via a with a corresponding power electronics 35 equipped electric motor 34 he follows. The compressor 33 may also be through a in the cathode exhaust path 32 arranged turbine 36 (optionally with variable turbine geometry) are supported by a common shaft (not shown) driven.

This in 1 shown fuel cell system 100 also has a conditioning module 40 on. The conditioning module 40 on the one hand is in the cathode supply path 31 arranged so that it can be flowed through by the cathode operating gas. For this purpose, the conditioning module has a gas inlet and a gas outlet. On the other hand, it is so in the cathode exhaust path 32 arranged so that it can be flowed through by the cathode exhaust gas.

The cathode supply 30 further includes a bypass valve disposed in a bypass line 37 on which the conditioning module 40 with the cathode supply line 31 so connects that conditioning module 40 upstream of the fuel cell stack 10 is not flowed through. The bypass valve 37 serves to control the amount of the conditioning module 40 immediate cathode operating medium.

All adjusting means 24 . 26 . 38 of the fuel cell system 100 can be designed as controllable or non-controllable valves or flaps. Corresponding further actuating means can be in the lines 21 . 22 . 31 and 32 be arranged to the fuel cell stack 10 isolate from the environment.

2 shows a schematic representation of a conditioning module 40 according to a first embodiment. The conditioning module 40 has a circular cylindrical inner first volume 42 on, the circumference of a circular cylindrical outer second volume 43 is surrounded. The first volume 42 thus has a first cross-sectional area 45 which are completely within a second cross-sectional area 46 of the second volume 43 is arranged. The conditioning module 40 also has a central circular cylindrical third volume 49 on, whose third cross-sectional area 50 within the first cross-sectional area 45 and the second cross-sectional area 46 is arranged. The first 42 , second 43 and third volume 44 are concentric circular cylinder volumes.

An operating medium of a fuel cell stack, according to the in 1 illustrated fuel cell system 100 in particular a through the compressor 33 compressed and heated cathode operating medium is via a gas inlet 41 into the conditioning module 40 initiated. The gas inlet 41 corresponds to the end face of the third volume formed as a gas distributor 49 , The third volume 49 extends as a circular cylindrical tube through the entire height of the conditioning module 40 and has on its lateral surface on a plurality of through holes, not shown, for the operating medium. Through this gas distributor, the operating medium flows along the entire height of the conditioning module 40 evenly in the radial direction into the third volume 49 downstream adjacent first volume 42 one.

The first volume 42 is designed as a heat exchanger, in particular as a cooler, and has a plurality of in the first volume 42 arranged heat transfer elements 47 on. It is in the axial direction and oriented in the radial direction, circumferentially evenly distributed in the first volume heat transfer plates 47 , The heat exchanger plates 47 be from a coolant, according to the in 1 illustrated fuel cell system 100 in particular from a cathode exhaust gas flows through. For this purpose, the conditioning module 40 a coolant inlet and a downstream, not shown, first coolant distributor region which adjoins the in 2 illustrated end face of the first volume 42 connects and the cathode exhaust the heat transfer elements 47 supplies. Furthermore, the conditioning module 40 a second coolant distributor region, not shown, which adjoins the in 2 not shown end face of the first volume 42 connects and the cathode exhaust gas via the downstream coolant outlet from the heat transfer elements 47 and the conditioning module 40 dissipates.

The over the gas distributor 49 in the first volume 42 radially inflowing operating medium flows along the heat transfer elements 47 radially outward. The operating medium is at the two heat exchanger surfaces each heat exchanger plate 47 Heat to the cathode exhaust gas as a coolant. The heat exchanger plates 47 are on a lateral surface of the first volume 42 attached, which also has a plurality of through holes for the operating medium. Through these openings, not shown, the operating medium flows in the radial direction in the second volume 43 one.

The second volume 43 is designed as a humidifier and has a plurality of humidifier elements arranged therein 48 on. These are axially extended hollow fiber membranes 48 , The hollow fiber membranes are made of a water and / or water vapor-carrying fluid, according to the in 1 illustrated fuel cell system 100 in particular from a cathode exhaust gas flows through. For this purpose, the conditioning module 40 a fluid inlet and a downstream, not shown, first fluid distribution region which conforms to the in 2 illustrated end face of the second volume 43 connects and the cathode exhaust gas to the hollow fiber membranes 48 supplies. Furthermore, the conditioning module 40 a second fluid distribution region, not shown, which adjoins the in 2 not shown end side of the second volume 43 connects and the cathode exhaust gas via the downstream fluid outlet from the hollow fiber membranes 48 and the conditioning module 40 dissipates.

That over the lateral surface of the first volume 42 in the second volume 43 incoming operating medium flows around the hollow-fiber membranes 48 and flows radially outward. In this case, the operating medium takes on the trained as a moisture transfer surfaces lateral surfaces of the hollow fiber membranes 48 Moisture from the fluid flowing through this. In particular, the lateral surfaces of the membranes 48 from the comparatively dry cathode operating medium (air) flows over, while the insides of the hollow fiber membrane 48 be overflowed by the relatively humid cathode exhaust gas (exhaust gas). Driven by the higher partial pressure of the water vapor in the cathode exhaust gas, there is a transfer of water vapor across the membrane 48 into the cathode working gas which is thus humidified. The hollow fiber membranes 48 are attached to or in the fluid distribution areas, not shown.

That in the first volume 42 cooled and in the second volume 43 moistened and thus conditioned operating medium finally enters via a in the lateral surface of the second volume 43 that are equal to the surface 51 of the conditioning module 40 is, arranged gas outlet 44 from the conditioning module 40 out. Again 1 As can be seen, the thus conditioned cathode operating medium is downstream of the conditioning module 40 arranged fuel cell stack 10 fed. The flow of the working fluid into, into and out of the conditioning module 40 is indicated by arrows.

3 shows a schematic representation of a conditioning module 40 according to a second embodiment. The conditioning module 40 has a circular cylindrical inner second volume 43 on, the circumference of a circular cylindrical outer first volume 42 is surrounded. The second volume 43 thus has a first cross-sectional area 45 which are completely within a second cross-sectional area 46 of the first volume 42 is arranged. The conditioning module 40 also has a central circular cylindrical third volume 49 on, whose third cross-sectional area 50 within the first cross-sectional area 45 and the second cross-sectional area 46 is arranged. The first 42 , second 43 and third 49 Volumes are concentric circular cylinder volumes. To the in 2 illustrated embodiment, identical components of in 3 presented conditioning module 40 have identical reference numerals like these and are not described again.

Unlike the in 2 illustrated embodiment of the conditioning module according to the invention 40 the operating medium flows over a in the lateral surface of the first volume 42 that simultaneously cover the surface 51 of the conditioning module 40 is, arranged gas inlet 41 radially inward into the first volume 42 one. This again has longitudinally oriented in the axial direction, oriented in the radial direction and as described above coolant flowing through heat transfer plates 47 along, along which the operating medium flows radially inward and is thereby cooled.

That in the first volume 42 cooled operating medium then flows through a plurality of passage openings in a lateral surface of the second volume 43 radially inward in this one. In the second volume 43 are in turn hollow-fiber membranes 48 arranged, which flows around the already cooled operating medium while absorbing moisture. The conditioned operating medium then flows radially inward and over a plurality of passage openings in a lateral surface of the third volume 49 into this one. The third volume 49 is designed as a gas collector and directs the conditioned operating medium via a downstream gas outlet 44 from the conditioning module 40 from.

4 shows a schematic representation of a conditioning module 40 according to a third embodiment. With regard to the relative arrangement of the first volume 42 and second volume 43 corresponds to the illustrated conditioning module 40 the in 2 shown. To this identical components of in 4 presented conditioning module 40 have identical reference numerals as in FIG 2 on.

Unlike the in 2 shown conditioning module 40 has the in 4 illustrated a variety of in the first volume 42 arranged heat transfer elements 47 in Form of heat exchanger tubes 47 a Rohrbündelwärmeübertragers on. The first volume 42 is by means of the heat exchanger surfaces of these heat exchanger tubes 47 designed as a heat exchanger. Unlike the one in 2 shown conditioning module 40 is in the in 4 illustrated conditioning module 40 no centrally located third volume 49 arranged as a gas distributor.

Instead, the conditioning module points 40 a first distributor region, not shown, which adjoins the illustrated end face of the first volume 42 followed. This first distributor region serves both to supply the operating medium to the first gas inlet 41 and the first volume 42 as well as the supply of the coolant to the heat exchanger tubes 47 , For this purpose, the first distributor region preferably has separate subregions which, for example, extend in the longitudinal direction of the cylindrical conditioning module 40 arranged one behind the other. For this purpose, the heat exchanger tubes 47 in the longitudinal direction of the conditioning module 40 over the illustrated end face of the first volume 42 out and into one of these sub-areas protrude.

The supplied operating medium flows from the gas inlet 41 in the first volume 42 and spreads in it in the axial and radial directions. That in the first volume 42 cooled operating medium finally passes over the lateral surface of the first volume 42 in the second volume 43 in which it by means of the humidifier elements arranged therein 47 is moistened. Finally, the conditioned operating medium occurs close to that in 4 not shown end face of the conditioning module 40 over the in the lateral surface of the second volume or in the surface 51 of the conditioning module 40 arranged gas outlet 44 out of this.

5 shows a schematic representation of a conditioning module 40 according to a fourth embodiment. With regard to the relative arrangement of the first volume 42 and second volume 43 corresponds to the illustrated conditioning module 40 the in 3 shown. To this identical components of in 5 presented conditioning module 40 have identical reference numerals as in FIG 2 and will not be explained again.

Also according to this embodiment, the first volume 42 heat-transfer elements 47 in the form of heat exchanger tubes 47 a Rohrbündelwärmeübertragers on. These are supplied with a coolant, for example cathode exhaust gas, via a first distributor region, not shown, which adjoins the in 5 illustrated end face of the first volume 42 followed. The operating medium is the conditioning module 40 over the in the lateral surface 51 arranged gas inlet 41 introduced, flows through it in the axial and counter to the radial direction, the first volume 42 and the second volume 43 and enters via a third volume designed as a gas collector 49 and the gas outlet 44 from the conditioning module 40 out. The second volume is associated with a water- or water-vapor-loaded fluid via a second distributor region, which adjoins the illustrated end face of the second volume 43 followed.

LIST OF REFERENCE NUMBERS

100

The fuel cell system

10

fuel cell stack

11

single cell

12

anode chamber

13

cathode space

14

Membrane electrode assembly (MEA)

15

Bipolar plate (separator plate, flow field plate)

20

anode supply

21

Anode supply line

22

Anode exhaust gas line

23

fuel tank

24

First actuating means

25

recirculation

26

Second actuating means

27

recirculation conveyor

28

water

30

cathode supply

31

Cathode supply line

32

Cathode exhaust gas line

33

compressor

34

electric motor

35

power electronics

36

Expander / turbine / control flap

37

bypass line

38

bypass valve

40

conditioning module

41

gas inlet

42

first volume

43

second volume

44

gas outlet

45

first cross-sectional area

46

second cross-sectional area

47

heat-transfer elements

48

moistener

49

third volume

50

third cross-sectional area

51

Surface of the conditioning module

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 7624971 B2 [0018]

Claims (10)

Conditioning module ( 40 ) for a working medium of a fuel cell stack ( 10 ), comprising: a gas inlet ( 41 ) for the operating medium; a flow-through, designed as a heat exchanger and downstream of the gas inlet ( 41 ) arranged first volume ( 42 ); a flow-through, designed as a humidifier and downstream of the first volume ( 42 ) arranged second volume ( 43 ); and a downstream of the second permeable volume ( 43 ) arranged gas outlet ( 44 ) for the conditioned operating medium, characterized in that in a cross-section of the conditioning module ( 40 ) a first cross-sectional area ( 45 ) of one of the first volume ( 42 ) and the second volume ( 43 ) within a second cross-sectional area ( 46 ) from the other of the first volume ( 42 ) and the second volume ( 43 ) is arranged. Conditioning module ( 40 ) according to claim 1, characterized in that in the first volume ( 42 ) coolant-flowing and connected to a coolant inlet and a coolant outlet heat transfer elements ( 47 ) and in the second volume ( 43 ) water or steam-carrying and at least with a fluid inlet connected humidifying elements ( 48 ) are arranged. Conditioning module ( 40 ) according to claim 1 or 2, characterized in that the first volume ( 42 ) and the second volume ( 43 ) Cylinder volume are. Conditioning module ( 40 ) according to one of the preceding claims, characterized in that the first cross-sectional area ( 45 ) and the second cross-sectional area ( 46 ) are concentric with each other and one of the gas inlet ( 41 ) and the gas outlet ( 44 ) near a center of the concentric cross-sectional areas ( 45 . 46 ) is arranged. Conditioning module ( 40 ) according to one of the preceding claims, further comprising a gas distributor and upstream of the first volume ( 42 ) or formed as a gas collector and downstream of the second volume ( 43 ) arranged, through-flowable third volume ( 49 ), wherein in a cross-section of the conditioning module ( 40 ) a third cross-sectional area ( 50 ) of the third volume ( 49 ) within the first cross-sectional area ( 45 ) and within the second cross-sectional area ( 46 ) is arranged. Conditioning module ( 40 ) according to one of the preceding claims, characterized in that a plurality of gas inlets ( 41 ) or gas outlets ( 44 ) on a surface ( 51 ) of the conditioning module ( 40 ) is arranged. Conditioning module ( 40 ) according to one of the preceding claims, characterized in that the first volume ( 42 ) and the second volume ( 43 ) are formed by mutually concentric circular cylinder. Fuel cell system ( 100 ) with a fuel cell stack ( 10 ), comprising an anode supply ( 20 ) with an anode supply path ( 21 ) and an anode exhaust path ( 22 ) and a cathode supply ( 30 ) with a cathode supply path ( 31 ) and a cathode exhaust path ( 32 ) and at least one in the anode and / or cathode supply ( 20 . 30 ) conditioning module ( 40 ) according to one of claims 1 to 7. Fuel cell system ( 100 ) according to claim 8, characterized in that a in the cathode supply ( 30 ) conditioning module ( 40 ) according to one of claims 2 to 7, a gas inlet ( 41 ) for a cathode operating medium and a gas outlet ( 44 ) for the conditioned cathode operating medium and a coolant inlet and a fluid inlet for a cathode exhaust gas. Vehicle with a conditioning module ( 40 ) according to one of claims 1 to 7 and / or a fuel cell system ( 100 ) according to one of claims 8 and 9.

Images