US20130120893A1 - Antistatic coating of fuel cell exhaust systems made of plastic - Google Patents
Antistatic coating of fuel cell exhaust systems made of plastic Download PDFInfo
- Publication number
- US20130120893A1 US20130120893A1 US13/297,881 US201113297881A US2013120893A1 US 20130120893 A1 US20130120893 A1 US 20130120893A1 US 201113297881 A US201113297881 A US 201113297881A US 2013120893 A1 US2013120893 A1 US 2013120893A1
- Authority
- US
- United States
- Prior art keywords
- exhaust system
- exhaust
- flow channel
- vehicle
- conductive
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
- F01N13/16—Selection of particular materials
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
- F01N13/18—Construction facilitating manufacture, assembly, or disassembly
- F01N13/1805—Fixing exhaust manifolds, exhaust pipes or pipe sections to each other, to engine or to vehicle body
- F01N13/1811—Fixing exhaust manifolds, exhaust pipes or pipe sections to each other, to engine or to vehicle body with means permitting relative movement, e.g. compensation of thermal expansion or vibration
- F01N13/1822—Fixing exhaust manifolds, exhaust pipes or pipe sections to each other, to engine or to vehicle body with means permitting relative movement, e.g. compensation of thermal expansion or vibration for fixing exhaust pipes or devices to vehicle body
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2510/00—Surface coverings
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M2008/1095—Fuel cells with polymeric electrolytes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2250/00—Fuel cells for particular applications; Specific features of fuel cell system
- H01M2250/20—Fuel cells in motive systems, e.g. vehicle, ship, plane
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02T90/40—Application of hydrogen technology to transportation, e.g. using fuel cells
Abstract
Description
- 1. Field of the Invention
- This invention relates generally to a plastic exhaust system for a fuel cell vehicle and, more particularly, to a plastic exhaust system for a fuel cell vehicle, where the exhaust system includes a conductive layer to dissipate electro-static charge.
- 2. Discussion of the Related Art
- Hydrogen is a very attractive fuel because it is clean and can be used to efficiently produce electricity in a fuel cell. The automotive industry expends significant resources in the development of hydrogen fuel cell systems as a source of power for vehicles. Such vehicles would be more efficient and generate fewer emissions than today's vehicles employing internal combustion engines. Fuel cell vehicles are expected to rapidly increase in popularity in the near future in the automotive marketplace.
- Proton exchange membrane fuel cells (PEMFC) are a popular fuel cell for vehicles. The PEMFC generally includes a solid polymer electrolyte proton conducting membrane, such as a perfluorosulfonic acid membrane. The anode and cathode typically, but not always, include finely divided catalytic particles, usually a highly active catalyst such as platinum (Pt) that is typically supported on carbon particles and mixed with an ionomer. The catalytic mixture is deposited on opposing sides of the membrane. The combination of the anode catalytic mixture, the cathode catalytic mixture and the membrane define a membrane electrode assembly (MEA). MEAs are relatively expensive to manufacture and require certain conditions for effective operation.
- Several fuel cells are typically combined in a fuel cell stack to generate the desired power. For example, a typical fuel cell stack for a vehicle may have two hundred or more stacked fuel cells. The fuel cell stack receives a cathode input gas, typically a flow of air forced through the stack by a compressor. Not all of the oxygen is consumed by the stack and some of the air is output as a cathode exhaust gas that may include water as a stack by-product. The fuel cell stack also receives an anode hydrogen input gas that flows into the anode side of the stack. In one known type of fuel cell system, the hydrogen gas fuel is injected into the anode side of the fuel cell stack by one or more injectors. The injector controls the amount of injected fuel for a particular stack current density based on pulse width modulation (PWM) control signal that controls the opening and closing of the injector.
- Typically, hydrogen gas for the fuel cell system is stored in a high pressure storage tank system including one or more interconnected pressure vessels on the vehicle to provide the hydrogen gas necessary for the fuel cell stack. The pressure within the vessels can be 700 bar or more. In one known design, the pressure vessels include an inner plastic liner that provides a gas tight seal for the hydrogen gas, and an outer carbon fiber composite layer that provides the structural integrity of the vessel.
- Unlike the exhaust of an internal combustion engine, the exhaust from a fuel cell stack on a vehicle is warm, but not hot, and thus the exhaust system of a fuel cell vehicle does not need to be configured of metal components. Therefore, it has been proposed in the art to configure the exhaust system of a fuel cell vehicle using plastic components to reduce the weight of the vehicle, reduce vehicle cost, etc. Further, because the exhaust from the fuel cell stack is warm, the exhaust pipes can be closely mounted to the underbody of the vehicle chasse without concern for damaging vehicle parts or heating the passenger compartment of the vehicle, as opposed to internal combustion engines which require a space between the exhaust gas line and the vehicle underbody. A representative plastic exhaust system for a fuel cell vehicle is disclosed in U.S. patent application Ser. No. 13/214,777, titled Underbody Integrated Exhaust Path for Fuel Cell Vehicles, filed Aug. 27, 2011, assigned to the assignee of this application, and herein incorporated by reference.
- Because the proposed plastic exhaust system for a fuel cell vehicle is to be made of a plastic material, it will have a low electrical conductivity. Thus, the water vapor and other exhaust materials that flow through the exhaust system will cause an electro-static charge build-up on the exhaust system that will not be significantly dissipated because of the non-conductive material. Once enough static charge builds up in the exhaust system, arcing could occur from the area on the exhaust system having the electro-static charge build-up to a conductive part on the chasse of the vehicle representing vehicle ground. Because the fuel cell stack exhaust may include some amount of hydrogen gas, which is highly flammable, this arcing potentially could ignite the hydrogen gas, which has obvious undesirable implications.
- In accordance with the teachings of the present invention, an exhaust system for a fuel cell vehicle is disclosed that is made of plastic. An inner surface of a flow pipe that is part of the exhaust system is coated with a conductive material. A conductive through bolt extends through the pipe to be electrically coupled to the conductive coating and chasse ground of the vehicle so that any electro-static charge build-up as a result of the flow of water vapor and exhaust through the pipe will be dissipated.
- Additional features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings.
-
FIG. 1 is a bottom view of a fuel cell vehicle showing a plastic exhaust system; -
FIG. 2 is a broken-away perspective view of a portion of a pipe of the plastic exhaust system shown inFIG. 1 and including an inner conductive layer; and -
FIG. 3 is a cross-sectional view of a portion of the exhaust system showing the inner conductive layer and a through bolt electrically coupled to chasse ground through an exhaust system bracket. - The following discussion of the embodiments of the invention directed to a plastic exhaust system for a fuel cell vehicle is merely exemplary in nature, and is in no way intended to limit the invention or its applications or uses. For example, the present invention has particular application for a fuel cell vehicle. However, as will be appreciated by those skilled in the art, the invention may have application for other vehicles and machines.
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FIG. 1 is a bottom view of afuel cell vehicle 10 showing avehicle chasse 12. Thevehicle 10 includes afuel cell stack 14 that receives hydrogen gas fuel from a hydrogen gasstorage tank system 16. Thefuel cell stack 14 generates a fuel cell stack exhaust that includes water vapor, liquid water, air, low levels of waste hydrogen gas and other trace elements. Anexhaust gas system 18 including anexhaust flow pipe 20 is coupled to thestack 14 to direct the stack exhaust to the environment in a manner that is well understood by those skilled in the art. -
FIG. 2 is a broken-away, perspective view of a section of thepipe 20 that is part of theexhaust system 18. Thepipe 20 includes an outerstructural layer 22 made of any suitable plastic material, such as a high density polyethylene, that forms the main structure of thepipe 20. Thepipe 20 also includes an innerconductive coating 24 made of a suitable conductive material, such as aluminum. Although aluminum is the conductive material used for this embodiment, those skilled in the art will readily appreciate that other conductive materials, including other metals and conductive non-metals, may be applicable for the conductive coating discussed herein. Further, thecoating 24 can be deposited on the inner surface of thestructural layer 22 by any suitable technique, such as a physical vapor deposition (PVD) process, spraying, etc. Further, theconductive coating 24 is provided on the inside surface of thestructural layer 22 in this embodiment. However, in alternate embodiments, it may be desirable to deposit a conductive coating on an outside surface of thelayer 22 or both the inside and outside surfaces of thelayer 22. - The
pipe 20 is intended to represent any, and possibly all, flow channels in theexhaust system 18, and because thestructural layer 22 is made of plastic and can be fabricated by any suitable plastic fabrication technique, such as blow molding, injection molding, extrusion, etc., and thecoating 24 is a very thin coating deposited by any applicable technique, thepipe 20 can have any cross-sectional shape or design, other than cylindrical, that is desirable for a particular vehicle exhaust system that can be formed by these fabrication techniques. For example, it may be desirable to make thepipe 20 as a rectangular profile. - When water vapor, water droplets, and other materials flow through the
pipe 20 from thefuel cell stack 14 through theexhaust system 18 to the environment, the electric-static charge that builds up within and on thepipe 20 will flow as a current in theconductive coating 24 if the coating is electrically coupled to ground. In one non-limiting embodiment, the polymer material of thelayer 22 may have a resistance of 1×1011 ohms and the aluminumconductive coating 24 may have a resistance of 2.65×10−2 ohms. - The electro-static charge that accumulates on the
conductive coating 24 needs to be discharged to ground in order to remove the charge and thus the spark potential.FIG. 3 is a cross-sectional view of thepipe 20 coupled to a bracket 28 that holds thepipe 20 to the under-side of thechasse 12. The bracket 28 is a metal bracket in this embodiment, such as a steel bracket, and is intended to represent any bracket suitable for mounting thepipe 20 to thechasse 12. The bracket 28 includes a pair oflegs holes chasse 12. Further, the bracket 28 includes asemi-spherical support portion 38 that corresponds to the shape of thepipe 20 for holding thepipe 20 to the bracket 28. A throughbolt 40 extends through thesupport portion 38 and anopening 44 in thestructural layer 22 and thecoating 24 to make electrical contact with thecoating 24. Thus, any electrical charge that builds up on theconductive coating 24 creates a current that flows through the throughbolt 40 to the bracket 48 and then to thevehicle chasse 12, representing vehicle ground. - It is noted that the bracket 28 is one bracket that may be used to mount the
exhaust system 18 to thevehicle 10. The length and complexity of the exhaust system would determine how many of the brackets 28 are need to support theexhaust system 18, where each bracket could include a through bolt for removing static charge build-up as described herein. - The foregoing discussion disclosed and describes merely exemplary embodiments of the present invention. One skilled in the art will readily recognize from such discussion and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the spirit and scope of the invention as defined in the following claims.
Claims (20)
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/297,881 US8432658B1 (en) | 2011-11-16 | 2011-11-16 | Antistatic coating of fuel cell exhaust systems made of plastic |
DE102012109431A DE102012109431A1 (en) | 2011-11-16 | 2012-10-04 | Antistatic coating of plastic fuel cell exhaust systems |
CN201210462674.4A CN103117403B (en) | 2011-11-16 | 2012-11-16 | Antistatic coating of fuel cell exhaust systems made of plastic |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/297,881 US8432658B1 (en) | 2011-11-16 | 2011-11-16 | Antistatic coating of fuel cell exhaust systems made of plastic |
Publications (2)
Publication Number | Publication Date |
---|---|
US8432658B1 US8432658B1 (en) | 2013-04-30 |
US20130120893A1 true US20130120893A1 (en) | 2013-05-16 |
Family
ID=48145294
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/297,881 Expired - Fee Related US8432658B1 (en) | 2011-11-16 | 2011-11-16 | Antistatic coating of fuel cell exhaust systems made of plastic |
Country Status (3)
Country | Link |
---|---|
US (1) | US8432658B1 (en) |
CN (1) | CN103117403B (en) |
DE (1) | DE102012109431A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20130146169A1 (en) * | 2011-12-08 | 2013-06-13 | GM Global Technology Operations LLC | Integrated shaped plastic exhaust system for fuel cell vehicles |
US10046893B2 (en) | 2016-04-11 | 2018-08-14 | National Research Council Of Canada | Pattenred film for forming fluid-filled blister, microfluidic blister, and kit and method of forming |
US10995651B2 (en) * | 2017-12-21 | 2021-05-04 | Faurecia Emissions Control Technologies, Germany Gmbh | Exhaust system for a combustion engine of a motor vehicle and motor vehicle |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6201980B2 (en) | 2014-12-25 | 2017-09-27 | トヨタ自動車株式会社 | Vehicle intake system |
JP6115559B2 (en) * | 2014-12-26 | 2017-04-19 | トヨタ自動車株式会社 | Vehicle exhaust system |
JP6146405B2 (en) * | 2014-12-26 | 2017-06-14 | トヨタ自動車株式会社 | Engine and engine manufacturing method |
JP6248962B2 (en) | 2015-02-10 | 2017-12-20 | トヨタ自動車株式会社 | Vehicle braking force generator |
JP6558313B2 (en) * | 2016-06-29 | 2019-08-14 | トヨタ自動車株式会社 | Vehicle and manufacturing method thereof |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5382359A (en) * | 1993-05-13 | 1995-01-17 | Parr Manufacturing, Inc. | Plastic fuel filter with conductive coating for providing an evaporative barrier and for dissipating electrostatic charges |
US5630866A (en) * | 1995-07-28 | 1997-05-20 | Gregg; Lloyd M. | Static electricity exhaust treatment device |
JP4455222B2 (en) * | 2004-08-19 | 2010-04-21 | 本田技研工業株式会社 | Intake / exhaust system member arrangement structure in fuel cell vehicle |
-
2011
- 2011-11-16 US US13/297,881 patent/US8432658B1/en not_active Expired - Fee Related
-
2012
- 2012-10-04 DE DE102012109431A patent/DE102012109431A1/en not_active Withdrawn
- 2012-11-16 CN CN201210462674.4A patent/CN103117403B/en not_active Expired - Fee Related
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20130146169A1 (en) * | 2011-12-08 | 2013-06-13 | GM Global Technology Operations LLC | Integrated shaped plastic exhaust system for fuel cell vehicles |
US8936220B2 (en) * | 2011-12-08 | 2015-01-20 | GM Global Technology Operations LLC | Integrated shaped plastic exhaust system for fuel cell vehicles |
US10046893B2 (en) | 2016-04-11 | 2018-08-14 | National Research Council Of Canada | Pattenred film for forming fluid-filled blister, microfluidic blister, and kit and method of forming |
US10995651B2 (en) * | 2017-12-21 | 2021-05-04 | Faurecia Emissions Control Technologies, Germany Gmbh | Exhaust system for a combustion engine of a motor vehicle and motor vehicle |
Also Published As
Publication number | Publication date |
---|---|
CN103117403B (en) | 2015-06-17 |
CN103117403A (en) | 2013-05-22 |
DE102012109431A1 (en) | 2013-05-16 |
US8432658B1 (en) | 2013-04-30 |
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Owner name: GM GLOBAL TECHNOLOGY OPERATIONS LLC, MICHIGAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:HEISE, AXEL;REEL/FRAME:027379/0871 Effective date: 20111111 |
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