Method for operating a fuel cell system of a motor vehicle, and motor vehicle

Abstract

A method for operating a fuel cell system of a motor vehicle includes the steps of: i) detecting whether a washing process of the motor vehicle in a wash facility for cleaning the exterior of the motor vehicle is taking place or is imminent and ii) reducing the supply of an oxidizing agent to a fuel cell stack of the fuel cell system when it has been detected that a washing process is taking place or is imminent.

Claims

1. A method for operating a fuel cell system of a motor vehicle, comprising the steps of: detecting whether a washing operation of the motor vehicle in a car wash for external cleaning of the motor vehicle is taking place or is imminent, wherein the washing operation is performed while the motor vehicle travels through the car wash; and reducing a feed of oxidizing agent to a fuel cell stack of the fuel cell system when it has been detected that the washing operation is taking place or is imminent, such that the feed of the oxidizing agent is reduced during the washing operation.

2. The method according to claim 1, wherein an oxidizing agent feeder is transferred into a rest state when it has been detected that the washing operation is taking place or is imminent.

3. The method according to claim 1, wherein the oxidizing agent is conducted past the fuel cell stack via at least one bypass.

4. The method according to claim 1, wherein stack shut-off valves of the fuel cell system are closed when it has been detected that the washing operation is taking place or is imminent.

5. The method according to claim 1, wherein the motor vehicle has a car wash mode, and the feed of oxidizing agent to the fuel cell stack is reduced when the car wash mode is or has been activated.

6. The method according to claim 1, wherein the motor vehicle detects the washing operation with consideration of a position of a driving direction selector lever.

7. The method according to claim 1, wherein different method steps are carried out in a case of a transfer of the fuel cell system into a state which provides electric energy after the washing operation than in the case of a startup of the previously deactivated fuel cell system.

8. A motor vehicle with a fuel cell system, the motor vehicle being configured to carry out the acts of: detecting whether a washing operation of the motor vehicle in a car wash for external cleaning of the motor vehicle is taking place or is imminent, wherein the washing operation is performed while the motor vehicle travels through the car wash; and reducing a feed of oxidizing agent to a fuel cell stack of the fuel cell system when it has been detected that the washing operation is taking place or is imminent, such that the feed of the oxidizing agent is reduced during the washing operation.

9. A motor vehicle with a fuel cell system, comprising: a control unit of the motor vehicle configured to: detect whether a washing operation of the motor vehicle in a car wash is taking place or is imminent, wherein the washing operation is performed while the motor vehicle travels through the car wash, and reduce feed of oxidizing agent to a fuel cell stack of the fuel cell system when it has been detected that the washing operation is taking place or is imminent, such that the feed of the oxidizing agent is reduced during the washing operation.

10. The motor vehicle according to claim 9, wherein the control unit is configured to transfer an oxidizing agent feeder into a rest state when it has been detected that the washing operation is taking place or is imminent.

11. The motor vehicle according to claim 9, wherein the motor vehicle comprises a car wash mode; and the control unit is configured to reduce the feed of oxidizing agent to the fuel cell stack when the car wash mode is or has been activated.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 is an embodiment of a fuel cell system with a cathode subsystem and an anode subsystem.

DETAILED DESCRIPTION OF THE DRAWING

(2) FIG. 1 is an embodiment of a fuel cell system with a cathode subsystem and an anode subsystem. The cooling circuit has been omitted here for reasons of simplicity. The oxidizing agent feeder 410 sucks in ambient air and compresses it. An air filter 412 which cleans the ambient air is arranged upstream of the oxidizing agent feeder 410. Here, an intercooler 420 for cooling the compressed ambient air is provided downstream of the oxidizing agent feeder 410. Here, the cathode-side bypass 460 branches off downstream of the intercooler 420, which bypass 460 opens into the cathode off-gas line downstream of the cathode K. Furthermore, the cathode-side stack shut-off valves 430, 440 are shown.

(3) The fuel cell stack 300 comprises a multiplicity of fuel cells which have not been shown here. Here, the fuel cell stack 300 is divided in a merely diagrammatic manner into a cathode K and into an anode A. In the anode inflow path, the anode subsystem comprises a fuel source H2, a shut-off valve 211 and a recirculation jet pump 234. Here, a water separator 232 and a recirculation pump 236 are provided downstream of the anode A. Furthermore, an anode flush valve 238 and an anode flush line 239 are provided downstream of the water separator 232.

(4) In one preferred refinement, the oxidizing agent feeder 410 is switched off if it has been detected that a washing operation in a car wash is taking place or is imminent. As an alternative, it can be provided that the oxidizing agent feeder 410 is operated further at a very low rotational speed and the oxidizing agent is discharged via the bypass 460. Furthermore, it can be provided that the cathode-side stack shut-off valves 430, 440 are closed if it has been detected that a washing operation in a car wash is taking place or is imminent.

(5) In the context of the technology disclosed herein, the term “substantially” (for example, “substantially perpendicular axis”) comprises in each case the precise property and/or the precise value (for example, “perpendicular axis”) and in each case deviations which are insignificant for the function of the property/the value (for example, “tolerable deviation from a perpendicular axis”).

(6) In the context of the technology disclosed herein, the term “is imminent” means that the motor vehicle is being prepared, for example, for passing through the car wash, or the passage through the car wash has just begun, and comprises, for example, a time period of less than 5 minutes or less than 2 minutes or less than 1 minute.

(7) The preceding description of the present invention serves merely for illustrative purposes and not for the purpose of the restriction of the invention. Within the context of the invention, various amendments and modifications are possible without departing from the scope of the invention and its equivalents.