Thermal management system and method of positioning and adjusting coolant flow for stationary vehicle fuel cell applications

The present disclosure relates to a thermal management system and method of adjusting and/or reversing coolant flow of a fuel cell system during stationary applications.

TECHNICAL FIELD

The present disclosure relates to a thermal management system and method of adjusting and/or reversing coolant flow of a fuel cell system during stationary applications.

BACKGROUND

Fuel cell systems are known for their efficient use of fuel to produce direct current (DC) and/or alternating current (AC) electric energy to power stationary applications (e.g., industrial applications) or mobile applications, such as a vehicle. Fuel cells used in vehicles, such as trains, buses, and trucks, often travel across long distances. Vehicles that travel substantial distances generally will experience starts and stops during a route, such that the vehicle transitions from being a mobile fuel cell application to a stationary fuel cell application.

Existing fuel cell systems typically have radiators that cool hot coolant exiting the fuel cell system. The radiators often comprise radiator fans that exhaust cooling air in a single direction during normal operations of the fuel cells or fuel cell stacks. For example, when the fuel cell is moving or mobile (e.g., on a moving vehicle), the radiator fans exhaust cooling air into the radiator and out into the environment. However, when the fuel cell is stationary (e.g., on a stationary vehicle), the standard radiator or radiator fan is unable to utilize energy provided by environmental factors, such as crosswinds, in order to continue its flow function.

The present disclosure is directed to a thermal management system and method of adjusting the flow of coolants (e.g., fluid, air and/or gases) when a fuel cell system, particularly a mobile fuel cell system, is stationary. The present method and system comprise reversing the direction of the radiator fan when the fuel cell and/or vehicle is stationary in order to maximize the energy utilized from environmental factors, such as wind. This solution permits continuous operation of a radiator fan with reversed air flow through a cooling radiator, which maximizes the efficiency of the thermal management system of the fuel cell system.

SUMMARY

Embodiments of the present disclosure are included to meet these and other needs.

In one aspect of the present disclosure, described herein, a method of operating a thermal management system in a vehicle includes the steps of operating a radiator, one or more fans, and a fuel cell system, slowing or stopping movement of the vehicle to a stationary position, reversing the direction of the one or more fans, drawings crosswinds into the radiator in an opposite direction, and continuing operation of the radiator and the fuel cell system during the stationary position. The radiator and the one or more fans are located on the top surface of the vehicle.

In some embodiments, the radiator, the one or more fans, and the fuel cell system may be located in a frame.

In some embodiments, the stationary position may include a vehicle speed that is at, about, or lower than about 15 km/hour. In some embodiments, the stationary position may include a vehicle speed that is at, about, or lower than about 20 km/hour.

In some embodiments, drawing crosswinds into the radiator in an opposite direction may include drawing ambient air into the radiator first and then through the one or more fans second. In some embodiments, drawing crosswinds into the radiator in an opposite direction may include drawing ambient air into the one or more fans first and then through the radiator second.

In some embodiments, the step of operating may further include operating a second radiator, the second radiator being coupled to one or more fans. In some embodiments, drawing crosswinds into the radiator in an opposite direction may include drawing ambient air into the radiator first, through the one or more fans second, through the one or more fans coupled to the second radiator third, and through the second radiator last.

In a second aspect of the present disclosure, a thermal management system for optimally cooling air in a stationary vehicle includes one or more adjusted fans, one or more radiators comprising crosswinds, and a frame. The adjusted fan directs air into one or more radiators in a direction opposite a normal fan. The frame positions the one or more radiators on the top-side of the stationary vehicle. The system may be an apparatus or embodied within an apparatus.

In some embodiments, the stationary vehicle may travel at a vehicle speed that is at, about, or lower than about 20 km/hour.

In some embodiments, the one or more radiators, the one or more adjusted fans, and the fuel cell system may be separately located on the top surface of the stationary vehicle. In some embodiments, the one or more radiators and the one or more adjusted fans may be positioned adjacent to the fuel cell system by at least 0.5 inches of a separation distance. In some embodiments, the separation distance may range from about 0.5 inches to about 12 inches.

In a third aspect of the present disclosure, a method of exhausting air of a thermal management system on a stationary train includes the steps of operating at least two radiators, at least two fans, and a fuel cell system, slowing or stopping movement of the stationary train to a stationary position that comprises a speed that is about or less than 20 km/hour, drawing air flow and crosswinds into at least one of the at least two radiators in an opposite direction of a normal fan, propelling the air flow and the crosswinds through at least one of the at least two radiators, and exhausting air out of at least one of the at least two radiators and the fuel cell system while the stationary train is in the stationary position.

In some embodiments, the at least two radiators, the at least two fans, and the fuel cell system may be located in a frame.

In some embodiments, the stationary position may include speed that is at, about, or lower than about 15 km/hour.

In some embodiments, the at least two radiators, the at least two fans, and the fuel cell system may be located on the top surface of the stationary train. In some embodiments, the at least two radiators, the at least two fans, and the fuel cell system may be separately located on the top surface of the stationary train. In some embodiments, the at least two radiators and the at least two fans may be positioned adjacent to the fuel cell system by at least 0.5 inches of a separation distance. In some embodiments, the separation distance may range from about 0.5 inches to about 12 inches.

These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings described herein. Reference is also made to the accompanying drawings that form a part of the present disclosure and show, by way of illustration of specific embodiments, in which ways the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice what is claimed and are not limiting. Instead, it is to be understood that other embodiments may be utilized and that logical mechanical and electrical changes may be made without departing from the spirit and scope of the invention and/or claims.

DETAILED DESCRIPTION

The present disclosure is related to a thermal management system120and method for adjusting the coolant36flow of a fuel cell system10. Adjusting the coolant36flow comprises changing, advancing, stopping, reversing, modifying, and/or impacting the flow of a coolant36through a fuel cell system10. A reactant32,34of the fuel cell system10includes, but is not limited to a fuel32and an oxidant34(e.g., air or oxygen).

As shown inFIG.1A, fuel cell systems10often include one or more fuel cell stacks12or fuel cell modules14connected to a balance of plant (BOP)16, including various components, to create, generate, and/or distribute electrical power for meet modern day industrial and commercial needs in an environmentally friendly way. As shown inFIGS.1B and1C, fuel cell systems10may include fuel cell stacks12comprising a plurality of individual fuel cells20. Each fuel cell stack12may house a plurality of fuel cells20connected together in series and/or in parallel. The fuel cell system10may include one or more fuel cell modules14as shown inFIGS.1A and1B.

Each fuel cell module14may include a plurality of fuel cell stacks12and/or a plurality of fuel cells20. The fuel cell module14may also include a suitable combination of associated structural elements, mechanical systems, hardware, firmware, and/or software that is employed to support the function and operation of the fuel cell module14. Such items include, without limitation, piping, sensors, regulators, current collectors, seals and insulators.

The fuel cells20in the fuel cell stacks12may be stacked together to multiply and increase the voltage output of a single fuel cell stack12. The number of fuel cell stacks12in a fuel cell system10can vary depending on the amount of power required to operate the fuel cell system10and meet the power need of any load. The number of fuel cells20in a fuel cell stack12can vary depending on the amount of power required to operate the fuel cell system10including the fuel cell stacks12.

The number of fuel cells20in each fuel cell stack12or fuel cell system10can be any number. For example, the number of fuel cells20in each fuel cell stack12may range from about 100 fuel cells to about 1000 fuel cells, including any specific number or range of number of fuel cells20comprised therein (e.g., about 200 to about 800). In an embodiment, the fuel cell system10may include about 20 to about 1000 fuel cells stacks12, including any specific number or range of number of fuel cell stacks12comprised therein (e.g., about 200 to about 800). The fuel cells20in the fuel cell stacks12within the fuel cell module14may be oriented in any direction to optimize the operational efficiency and functionality of the fuel cell system10.

The fuel cells20in the fuel cell stacks12may be any type of fuel cell20. The fuel cell20may be a polymer electrolyte membrane or proton exchange membrane (PEM) fuel cell, an anion exchange membrane fuel cell (AEMFC), an alkaline fuel cell (AFC), a molten carbonate fuel cell (MCFC), a direct methanol fuel cell (DMFC), a regenerative fuel cell (RFC), a phosphoric acid fuel cell (PAFC), or a solid oxide fuel cell (SOFC). In an exemplary embodiment, the fuel cells20may be a polymer electrolyte membrane or proton exchange membrane (PEM) fuel cell or a solid oxide fuel cell (SOFC).

In an embodiment shown inFIG.1C, the fuel cell stack12includes a plurality of proton exchange membrane (PEM) fuel cells20. Each fuel cell20includes a single membrane electrode assembly (MEA)22and a gas diffusion layer (GDL)24,26on either or both sides of the membrane electrode assembly (MEA)22(seeFIG.1C). The fuel cell20further includes a bipolar plate (BPP)28,30on the external side of each gas diffusion layers (GDL)24,26. The above mentioned components,22,24,26,30comprise a single repeating unit50.

The bipolar plates (BPP)28,30are responsible for the transport of reactants, such as fuel32(e.g., hydrogen) or oxidant34(e.g., oxygen, air), and cooling fluid36(e.g., coolant and/or water) in a fuel cell20. The bipolar plate (BPP)28,30can uniformly distribute reactants32,34to an active area40of each fuel cell20through oxidant flow fields42and/or fuel flow fields44. The active area40, where the electrochemical reactions occur to generate electrical power produced by the fuel cell20, is centered within the gas diffusion layer (GDL)24,26and the bipolar plate (BPP)28,30at the membrane electrode assembly (MEA)22. The bipolar plate (BPP)28,30are compressed together to isolate and/or seal one or more reactants32within their respective pathways, channels, and/or flow fields42,44to maintain electrical conductivity, which is required for robust during fuel cell20operation.

The fuel cell system10described herein, may be used in stationary and/or immovable power system, such as industrial applications and power generation plants. The fuel cell system10may also be implemented in conjunction with electrolyzers18and/or other electrolysis system18. In one embodiment, the fuel cell system10is connected and/or attached in series or parallel to an electrolysis system18, such as one or more electrolyzers18in the BOP16(seeFIG.1A). In another embodiment, the fuel cell system10is not connected and/or attached in series or parallel to an electrolysis system18, such as one or more electrolyzers18in the BOP16.

The present fuel cell system10may also be comprised in mobile applications. In an exemplary embodiment, the fuel cell system10is in a vehicle and/or a powertrain100. A vehicle100comprising the present fuel cell system10may be an automobile, a pass car, a bus, a truck, a train, a locomotive, an aircraft, a light duty vehicle, a medium duty vehicle, or a heavy duty vehicle.

The vehicle and/or a powertrain100may be used on roadways, highways, railways, airways, and/or waterways. The vehicle100may be used in applications including but not limited to off highway transit, bobtails, and/or mining equipment. For example, an exemplary embodiment of mining equipment vehicle100is a mining truck or a mine haul truck.

Referring toFIGS.2A and2B, a powertrain or vehicle100is illustratively embodied as a train100. The train100is shown to have a top external surface112that is above an inner region15(e.g., above the train coach). Fuel cell systems10and fuel tanks114comprising fuel32may be mounted, positioned, and/or located on either or both of the top external surface112and the inner region15, as shown inFIGS.2A and2B. In some embodiments, the fuel cell systems10and fuel tanks114are only mounted, positioned, and/or located on the top external surface112of the vehicle100.

Fuel tanks114are typically connected to one or more power sources116. In one embodiment, a powertrain or vehicle100may be powered by one or more, and typically more than one, of any type of a power source116. A power source116of the present method or system may include but is not limited to an engine (e.g., an internal combustion engine (ICE), a diesel engine, a hydrogen powered engine, etc.) (not shown), a fuel cell system10, and/or a battery system160. A typical hybrid powertrain or vehicle100may comprise at least two different types of power sources116(e.g., an engine, a fuel cell system10, a battery system160, etc.).

In an illustrative embodiment, a hybrid powertrain or vehicle100may comprise a fuel cell system10and a battery system160. An exemplary battery system160is a high powered battery system having an energy capacity ranging from about 80 kWh to 150 kWh. An exemplary powertrain or vehicle100may include at least one fuel cell system10and at least one high voltage battery system160, as shown inFIG.2A. In a further embodiment, the powertrain or vehicle100may comprise additional power sources116, such as a diesel engine and/or a hydrogen powered engine (not shown), in addition to the fuel cell system10and/or the high voltage battery system160.

In one embodiment, the powertrain or vehicle100may comprise one fuel cell system10. In other embodiment, such as shown inFIG.2A, the powertrain or vehicle100may comprise more than one fuel cell system10. In some embodiments, the fuel cell system10may comprise about 2 to 20 fuel cell systems10, including any specific number or range comprised therein. Some embodiments of the powertrain or vehicle100may comprise about 2 to 3 fuel cell systems10, about 4 to 8 fuel cell systems10, or about 8 to 10 fuel cell systems10.

In one embodiment, the powertrain or vehicle100may comprise one or more battery systems160(e.g., a high voltage battery system160). In one embodiment, the powertrain or vehicle100may comprise about 1 to 10 battery systems160, including any number or range comprised therein (e.g., 1, 2, 3, 4, 5, etc.), such as is shown inFIG.2A. In one illustrative embodiment, the powertrain or vehicle100may comprise only one high voltage battery system160. In another illustrative embodiment, the powertrain or vehicle100may comprise more than one high voltage battery system160.

In some embodiments, the powertrain or vehicle100may comprise additional components. In some embodiments, the powertrain or vehicle100may comprise a converter124,126. For example, the powertrain or vehicle100may comprise an auxiliary converter124or a traction converter126. In other embodiments, the powertrain or vehicle100may comprise a motor128(e.g., a traction motor128).

Referring toFIGS.3A and3B, in addition to the fuel cell system10, the battery system160, and any additional components, the powertrain or vehicle100may further comprise a thermal management system120. The thermal management system120of the present disclosure manages the heat35, air39, and/or gases produced by a fuel cell system10in order to remove heat35and cool the fuel cell system10efficiently and effectively in order to maintain acceptable operating temperatures. The thermal management system120may automatically, electronically, manually measure, sample, or otherwise control and manage heat35dissipated by a radiator118and/or exhaust117.

As shown inFIGS.3B-8, a thermal management system120of the powertrain or vehicle100comprises, is configured to be connected to, or configured to communicate with one or more fuel cell systems10, one or more radiators118, a pump19, a motor220, one or more radiator fans122, and/or an exhaust system117, either individually or in combination with each other. In an exemplary embodiment, the thermal management system120comprises at least two radiators118for each fuel cell system10. Further, the thermal management system120may also comprise one or more external coolant flow passages, ports, nozzles, misters, sensors, and/or other components to provide sufficient heat35, air39, or coolant36dissipation in order to keep the fuel cell system10within desired operating temperature specifications.

Referring toFIGS.2B,3B, and4, components of the thermal management system120may be structurally and/or physically configured or connected to the fuel cell system10in a frame or brace132. In other embodiments, components of the thermal management system120may not be structurally and/or physically configured or connected to the fuel cell system10in a frame or brace132at all. In some embodiments, the frame or brace132physically houses the thermal management system120and/or the fuel cell system10in order to provide structural stability and operational protection of the components of those systems.

Referring toFIGS.2B to6, in some embodiments, the frame or brace132comprises a closed bottom structure134that encases the components of the thermal management system120for more structural and vibrational stability. In some embodiments, the closed bottom134of the frame or brace132may separate the thermal management system120and its components from the fuel cell system10and its components in order to provide more structural stability and operational protection of the components of those systems. The frame or brace132may be made of any material known in the art to provide structural stability to a fuel cell system10, such as metal, steel, stainless steel, or combinations thereof.

Importantly the frame or brace132positions, locates and/or connects the one or more radiators118to the vehicle or train100. Specifically, in one embodiment, the radiators118are located on the top surface112of the train100. In another embodiment, the radiators118are not facing the front113of the train100. In another embodiment, the radiators118are located on a top-side surface38of the train100, such that the radiators118do not directly encounter and/or benefit from headwinds (seeFIG.2B).

In one embodiment of the present thermal management system120, as illustrated inFIGS.4and6-8, the radiator118may not be placed below or in a lower plane as the fuel cell system10. Instead, the radiator118may be located above or in a higher plane than the fuel cell system10. For example, as shown inFIGS.3B-8, the thermal management system120comprising the radiator118and fans122is located on top surface112of the vehicle or train100, while the fuel cell system10is located inside the inner region15of the train100, below the radiator118.

The motor220is utilized to power the fans122and/or the radiator118of the thermal management system120. In some embodiments, the motor220of the thermal management system120may be powered by the fuel cell system10. In some embodiments, a pump19may be comprised by the thermal management system120to circulate the coolant36(e.g., main or secondary fluids) and/or to drive water36against gravity to the radiator118located above the fuel cell system10.

As illustrated inFIGS.3B-8, an exemplary thermal management system120may manage the heat35, air39, coolant36, and/or gases produced by the fuel cell system10using a radiator118. Reactants32,34(e.g., fuel and air) and coolants36(water, air, and/or fluids)30may be put in, flow through, and/or exit or exhaust from the fuel cell system10. For example, a main fluid (e.g., a coolant)36may exit the fuel cell system10at a high temperature, remove heat35from the fuel cell system10, and/or reach the radiator160while passing through the thermal management system120.

A coolant36of the thermal management system120may comprise any material that is capable of removing heat35from the fuel cell system10. The coolant36is useful in order to reduce the temperature generated by operation of a fuel cell system10. Typically, the coolant36removes heat35from the fuel cell system10and transfers it to one or more radiators118.

In one embodiment, the coolant36may be gases (e.g., hydrogen, nitrogen, carbon dioxide, etc.), solids, and/or liquids. In an exemplary embodiment, the coolant36may be a liquid, such as water, freon or other heat transferring liquids. The coolant36may also be a main fluid36of the thermal management system120, which may further comprise a secondary fluid37. Cooled coolant36exiting the thermal management system120may be recirculated back to fuel cell system10to absorb more heat35in order to cool the fuel cell system10.

A secondary fluid37of the thermal management system120may remove heat35from the main fluid36(e.g., the coolant36). The secondary fluid37of the thermal management system120often removes heat35from the main fluid36(e.g., the coolant) located at the radiator118and exhausts the heat35to the atmosphere. In one embodiment, an exemplary secondary fluid37of the thermal management system120may be an oxidant34, such as air or oxygen. In another embodiment, the secondary fluidic air37is atmospheric air or wind that removes heat35from the coolant30at the radiator118and delivers the heat35to the atmosphere in order to cool the fuel cell system10.

In some embodiments, to aid in heat35dissipation, the present thermal management system120may further comprise one or more fans122. Fans122provide airflow to speed the dissipation of heat35, air39, and/or gases from the radiator118and fuel cell system10, respectively and collectively. In other embodiments, a fan122may be provided to help dissipate heat35away from the radiator118of the thermal management system120. A fan122also enables the additional benefit of removing debris from the fuel cell system10or the thermal management system120. Such fans122may be rated to supply a desired air speed (e.g., at or about 50 mph) in order to cool the heat35, air39, and/or coolant36in the thermal management system120and fuel cell system10of the powertrain or vehicle100.

As shown inFIG.4, one or more fans122may be located near, next to, or comprised by the radiator118. In some embodiments, there may be one or more fans122configured or connected to each radiator118. In an illustrative embodiment, about one (1) to about five (5) fans122may be associated with each radiator118, including any number or range of fans comprised therein. In an exemplary embodiment, about three (3) fans122may be associated, connected to, and/or configured to dissipate heat35from one radiator118(seeFIG.4).

In a standard air flow pattern of the thermal management system120, ambient air39may enter the system120through an air inlet131at the middle corridor of the frame or brace132. A single fan122may direct air flow to the radiator118from right to left or in the East-to-West direction. In some embodiments, a single fan122may direct air flow to the radiator118from left to right or in the West-to-East direction. In some further embodiments, more than one fan122may direct air flow to the radiator118from both directions.

FIG.5demonstrates a standard air flow pattern of a thermal management system120comprising two (2) radiators118,119(e.g., three (3) fans122per radiator), such as when a vehicle or train100is moving. Ambient air39may also enter this system120through an air inlet131at the middle corridor of the frame or brace132. However, the fans122for the first radiator118may direct air flow to the first radiator118, such as from left to right or in the West-to-East direction. Similarly, the fans122for the second radiator119may direct air flow to the second radiator119, such as from right to left or in the East-to-West direction. In some embodiments, the thermal management system120may span about 1910 mm along the length of the top surface112of the train. In other embodiments, the thermal management system120may be longer or shorter than about 1910 mm.

In this standard embodiment, hot air133is exhausted or pushed out of the two radiators118,119the fuel cell system10, and the thermal management system120into the environment. Often, when the powertrain or vehicle100is moving, the hot air133is exhausted into the wind from the radiators118,119located in the middle of the vehicle100. Air exhaust from the thermal management system120is relatively easy when headwinds experienced during movement of the train or vehicle100aid in the exhaust and thermal management of the fuel cell system10.

More specifically, headwinds provide fast moving air that flows through the radiator118. Typically, headwinds flow from the front-to-back of the radiator118and/or in the opposite direction that the vehicle or train100. Headwinds can significantly aid in the cooling of air and/or coolants via the thermal management system120when the vehicle or train100is in movement. Headwinds are particularly advantageous when the train100is moving at high speeds (e.g., about or greater than 15 to 160 kilometers per hour).

When the vehicle or train100is stationary, headwinds are not readily available and do not significantly influence or contribute to thermal management of the fuel cell system10. In one embodiment, stationary refers to when the wind speed (e.g., headwinds) drops below the exhaust velocity of the thermal management system120. In one embodiment, when the exhaust velocity from the radiators118,119of the thermal management system120drops below about 6 meters/second then the vehicle and/or train100is considered to be stationary.

In another embodiment, stationary refers to when a vehicle or train100is not moving at all and when the vehicle or train100is moving at low or minimal speeds. Low speeds comprise speeds of less than about 15 to about 20 km/hour, including any specific or range of speeds comprised therein, which represents the normal average wind speed on a regular day (e.g., as specified for any geographic area). At low speeds or when a vehicle or train100is stationary, there is a significant advantage realized in utilizing the crosswinds that flow perpendicular to the radiators118,119to aid the efficiency and performance of the thermal management system120.

Accordingly, the present thermal management system120and method are directed to cooling air or other coolants when a vehicle or train100is stationary. More specifically, the thermal management system120and method reverse the direction of the air flow through the radiators118of the thermal management system100. in order to enable continuous cooling operations of the fuel cell system10when stationary.

For example in one embodiment, the system120and method utilize crosswinds to reverse direction of the air flow through the radiators118,119. In another embodiment, the system120and method comprise fans122to reverse the direction of the air flow through the radiators118,119. In yet other embodiments, the system120and method comprise crosswinds, fans, and/or any other means to reverse direction of the air flow through the radiators118,119.

Referring toFIG.6, the present thermal management system120and method utilize crosswinds that typically have speeds greater than the air and/or coolant exhaust velocity of the radiators118,119(e.g., about 6 meters/second). Accordingly, the radiator fans122may draw in ambient crosswinds and bolster cooling effects. In particular, the radiator fan122direction may be reversed to draw in ambient crosswind air flow that more efficiently cools air in the radiators118,119, rather than to blow out hot air.

In one embodiment shown inFIGS.6and7, the direction of a fan122of a first radiator118has been reversed. More specifically, the direction of the fan of the first radiator118has been changed or switched to intake or draw in air rather than push out air. In particular, the fan122of the first radiator118ofFIG.6utilizes crosswind air that may flow (as indicated by the arrows) in the East-to-West direction, such as from the atmosphere into a first radiator118of the thermal management system120. The air flow of the reversed fan122of the first radiator118may continue across and/or through the second radiator119to the environment since the direction of the fan122of the second radiator119remains unchanged. In a separate embodiment, air may also flow in the opposite direction that is shown inFIG.6, such as in the West-to-East direction, into the second radiator119, and out of the first radiator118.

In yet a further embodiment of the thermal management system120shown inFIGS.5to7, the direction of both fans122, such as of the first radiator118and the second radiator119, may be reversed. More specifically, the direction of the fan122of the first radiator118may be changed or switched to intake or draw in air and push out air in the East-to-West direction rather than the West-to-East direction shown inFIG.5. In addition, the direction of the fan122of the second radiator119may be changed or switched to intake or draw in air and push out air in the West-to-East direction rather than the East-to-West direction shown inFIG.5. In addition, the fans122of the first118and second radiators119may utilize crosswind air that may flow counter to the direction indicated by the arrows inFIG.5.

FIG.7demonstrates an embodiment of the present thermal management system120when located at the driver's end of a vehicle or train100. Similar toFIG.5, the solid arrows ofFIG.7indicate the standard flow of air or coolant of a vehicle or train100. The dashed arrows indicate the reversed air or coolant flow of the vehicle or train100using the present thermal management system120comprising air flow in the East-to-West direction into a first radiator118and out of a second radiator119.

FIG.8demonstrates one embodiment of the present thermal management system120when the radiator118comprises only one fan122. In such an embodiment, the direction of the single fan122of the radiator118may be reversed. More specifically, the direction of the fan122of the radiator118may be changed or switched to draw in crosswind air that may flow (as indicated by the dashed arrows) in the East-to-West direction, such as from the atmosphere into the radiator118, across and/or through the other side to the environment (e.g., through a mesh). In another embodiment, the single fan122may push air flow in the opposite direction that is shown inFIG.7, such as in the West-to-East direction, into the bottom, and out of the top of the single radiator118.

In one embodiment, the present vehicle or train100, including its thermal management system120and/or the fuel cell system10, comprise one or more sensors (not shown). In one embodiment, sensors may detect operational or functional parameter of the fuel cell system10(e.g., the radiator118and/or coolant system400) and when those parameters drift outside of proper or manufacturer operating specifications. In one embodiment, sensors may comprise air, wind, sensors, and/or temperature sensors. In one embodiment, the one or more sensors may be connected, attached, mounted on, and/or configured to communicate with the thermal management system120(e.g., the radiators118and the fans122) and/or the fuel cell system10(e.g. the fuel cells20).

In one embodiment, sensors communicate with radiator fans122to turn on, turn off, turn in one direction, turn in a different direction, slow down, speed up, etc. Sensors communicate with radiator fans in the thermal management system120in order to maintain the fuel cell operating temperature and air flow within an acceptable operating threshold.

In some embodiments, the method steps of reversing the direction of air flow, including 1) detecting the coolant flow or temperature with a sensor, 2) utilizing environmental crosswinds, and 3) reversing the direction of the radiator fans122, may be performed manually, automatically, electronically, by a person, by a robot, by an instrument or using equipment. In an illustrative embodiment, the method may be performed manually by a human, such as a train operator, service technician, and/or conductor. In another embodiment, the method may be performed electronically and/or automatically by a robot, a machine, or a computer.

Alternatively or additionally, as shown inFIG.9, the thermal management system120includes an air handling system, which is the thermal management system120as described above, and further includes a cooling system400. The cooling system400thermally manages the fuel cell system10with coolant36and comprises, is configured to be connected to, or configured to communicate with one or more fuel cell systems10, one or more radiators118, a pump19, a motor220, a coolant heater402, and a pump motor speed controller404, either individually or in combination with each other. The disclosures of the air handling system120(thermal management system120), fuel cell system10, the coolant36, the radiator118, the pump19, and the motor220are incorporated by reference for the cooling system400except for the differences explicitly described below.

In the illustrative embodiment, the cooling system400is connected to the radiator118of the air handling system120as well as the fuel cell system10. The cooling system400includes the pump19, the motor220, the coolant heater402, and the pump motor speed controller404. In some embodiments, the cooling system400may include more than one pump19, more than one motor220, more than one coolant heater402, and/or more than one pump motor speed controller404. In some embodiments, the pump motor speed controller404may be electrically connected to the air handling system120and/or the vehicle or train100.

The pump19, controlled by the motor220, drives the coolant36through the cooling system400and the fuel cell system10. The coolant36may be a liquid, such as water, freon or other heat transferring liquids. The pump motor speed controller404is electrically coupled to the motor220and adjusts the speed of motor220to manipulate a flow rate of the coolant36. In some embodiments, the speed of the motor220may range from about 2500 revolutions per minute (RPM) to about 3000 RPM. The speed of the motor220may be less than about 2500 RPM and/or greater than about 3000 RPM. For example, at or shortly after the beginning of life of one or more fuel cell stacks12and/or fuel cell modules14of the fuel cell system10, the speed of the motor220may be less than about 3000 RPM, then increased to 3000 RPM, and then slowed down to about 2500 RPM. As the one or more fuel cell stacks12and/or fuel cell modules14age, the speed of the motor220may increase from about 2500 RPM to manipulate the flow rate of the coolant36to compensate for reduced efficiency of the one or more fuel cell stacks12and/or fuel cell modules14of the fuel cell system10. The flow rate of the coolant36is inferred from the speed of the motor220and/or the pump19, and may also be measured with a coolant flow sensor416.

Manipulating the flow rate of the coolant36maintains an operating temperature of the fuel cell system10. In some embodiments, the operating temperature of the fuel cell system10may range from about 65° C. to about 67° C. The operating temperature of the fuel cell system10may be less than about 65° C. and/or greater than about 67° C. depending on the type of fuel cells20of the fuel cell system10.

The cooling system400also includes one or more valves and one or more sensors to control and monitor the temperature and flow rate of the coolant36. The one or more valves include a first flow control valve406, a second flow control valve407, a mixing valve408, and a bypass valve410. The one or more sensors include a first temperature sensor412, a second temperature sensor413, a coolant pressure sensor414, and/or a coolant flow sensor416.

In some embodiments, the cooling system400may have more or less valves and/or sensors than described above. The one or more sensors and the one or more valves are electrically coupled to the pump motor speed controller404. In some embodiments, the one or more sensors and the one or more valves may be electrically coupled to the air handling system120and/or the vehicle or train100.

In the illustrative embodiment, the coolant36flows from the pump19through the first flow control valve406. The coolant pressure sensor414and the coolant flow temperature416are positioned between the pump19and the first flow control valve406to detect the pressure and flow of the coolant36leaving the pump19. The coolant36then flows to the mixing valve408, where the mixing valve408disperses the coolant36to the one or more radiators118and the coolant heater402. The coolant heater402heats the coolant36, while the one or more radiators118cool the coolant36.

Depending on whether the one or more fuel cell stacks12and/or fuel cell modules14need to be heated or cooled, the heated coolant36may flow through the bypass valve410and/or to the one or more fuel cell stacks12and/or fuel cell modules14. Likewise, the cooled coolant36may flow through the bypass valve410and/or to the one or more fuel cell stacks12and/or fuel cell modules14.

The first temperature sensor412monitors and detects the temperature of the coolant36entering the one or more fuel cell stacks12and/or fuel cell modules14. The second temperature sensor413monitors and detects the temperature of the coolant36exiting the one or more fuel cell stacks12and/or fuel cell modules14. As the coolant36flows from the one or more fuel cell stacks12and/or fuel cell modules14through the second flow control valve407towards the pump19, the pump motor speed controller404calculates the difference between the temperature of the coolant detected by the first temperature sensor412and by the second temperature sensor413. The pump motor speed controller404then increases, decreases, or maintains the speed of the motor220to increase, decrease, or maintain the flow rate of the coolant36as it exits the pump19. In some embodiments, the one or more valves and the one or more sensors may be positioned anywhere along the coolant36flow path.

Finally,FIG.10demonstrates a side-by-side positioning layout of the thermal management system120comprising the radiator118and fans122that is located on the same surface and/or in the same plane as the fuel cell system10. For example, the thermal management system120comprising the radiator118and fans122is located on the same top surface112of the vehicle or train100, while the fuel cell system10is also located on the same top surface112of the vehicle or train100.

In other such embodiments, the radiator118of the thermal management system120and the fuel cell system10may be positioned or located on the same plane and in any position or location that provides operational efficiency, assessment, maintenance, and/or repair of the fuel cells20. Notably,FIG.10demonstrates an advantageous side-by-side system layout embodiment.

In one such embodiment, the fuel cell power generating components of the fuel cell system10are distinctly and separately located adjacent to the main cooling system400/120components of the thermal management system120. This specific side-by-side layout design comprising the thermal management system120located adjacent to and separately from the fuel cell system10provides some benefits over other layout embodiments described herein (e.g.,FIGS.3B-8).

Importantly, the side-by-side layout demonstrated inFIG.10allows that the fuel cells20are more easily accessible for servicing without significant disturbance to the cooling400/120and other sub-systems of the thermal management system120. This layout side-by-side ofFIG.10also facilitates redesign, resizing, and/or repositioning of one or both of the thermal management (e.g., cooling) system120and the fuel cells20of the fuel cell system10, which can be increased or decreased independently of each other, if required. This additional flexibility of the side-by-side positioning of the fuel cell system10and thermal management system120significantly reduces the time and number of components that would need to be redesigned in any new system.

Additionally, the improved efficiency and effectiveness provided by the side-by-side design of the of the fuel cell system10and thermal management system120lies in that the fuel cells20remain separated from the cooling system400/120. In some embodiments, the fuel cell system10and thermal management system120are separated by a distinct, uniform, or non-uniformly shaped separation distance150that ranges from about 0.5 inch to about 12 inches in width, including any and all specific or range of distances comprised therein. In some embodiments, the separation distance150is uniformly shaped, such as in a straight line, that has a separation distance or thickness150ranging from about 0.5 inch to about 12 inches thick, including all specific or range of thickness150comprised therein.

In another embodiment, the separation distance150between the fuel cell system10and thermal management system120may ranges from about 0.5 to about 12 inches long, including all specific or range of distances comprised therein. Side-by-side and distinct separation of the fuel cells of the fuel cell system10from the radiators118and other components of the thermal management system120enable easy accessibility to the fuel cells20or fuel cell system10components for servicing. The side-by-side positioning of the fuel cell system10and thermal management system120also minimizes or reduces the amount or need for disassembly of other components and disturbing significant parts of other subsystems in order to reach the fuel cells20of the fuel cell system10.

For example, the present side-by-side layout of the fuel cell system10and the thermal management system120may be and/or is an improvement over the layouts described inFIGS.3B-8. Illustratively, the side-by-side layout of the fuel cell system10and the thermal management system120is advantageous over alternative layouts, wherein the radiators118may be located or positioned over top, atop, or on top of the fuel cell systems10, thereby requiring that the cooling or thermal management system120be moved or removed before the fuel cell system10components are accessible for assessment, maintenance, and/or repair. Therefore, the present side-by-side layout of the fuel cell system10and the thermal management system120, as shown inFIG.10, also facilitates the design of other iterations of the present invention as the fuel cell10and cooling systems400/120can be increased or decreased in scope and size, independently.

For example, if more cooling is needed because the presently claimed system and methods are going to be deployed in a part of the world having hot, ambient temperature, the side-by-side positioning of the present fuel cell system10and thermal management system120would easily allow or enable expansion of the cooling system400/120on its distinct side to include longer or larger radiators118. In turn, expanding or enlarging the radiators118to allow for the required cooling in hot temperatures would be conducted without affecting the components of the fuel cell system10on its side. The independent ability to access the fuel cell system10and the thermal management system or cooling system400/120separately and independently also thereby advantageously minimizes any redesign efforts and increasing cooling and thermal management efficiency.

The following described aspects of the present invention are contemplated and non-limiting:

A first aspect of the present invention relates to a method of operating a thermal management system in a vehicle. The method includes the steps of operating a radiator, one or more fans, and a fuel cell system, slowing or stopping movement of the vehicle to a stationary position, reversing the direction of the one or more fans, drawings crosswinds into the radiator in an opposite direction, and continuing operation of the radiator and the fuel cell system during the stationary position. The radiator and the one or more fans are located on the top surface of the vehicle.

A second aspect of the present invention relates to a thermal management system for optimally cooling air in a stationary vehicle. The system includes one or more adjusted fans, one or more radiators comprising crosswinds, and a frame. The adjusted fan directs air into one or more radiators in a direction opposite a normal fan. The frame positions the one or more radiators on the top-side of the stationary vehicle. The system may be an apparatus or embodied within an apparatus.

A third aspect of the present invention relates to a method of exhausting air of a thermal management system on a stationary train. The method includes the steps of operating at least two radiators, at least two fans, and a fuel cell system, slowing or stopping movement of the stationary train to a stationary position that comprises a speed that is about or less than 20 km/hour, drawing air flow and crosswinds into at least one of the at least two radiators in an opposite direction of a normal fan, propelling the air flow and the crosswinds through at least one of the at least two radiators, and exhausting air out of at least one of the at least two radiators and the fuel cell system while the stationary train is in the stationary position.

A fourth aspect of the present invention relates to thermally managing and operating a fuel cell system in a vehicle with a cooling system. The method includes the steps of determining a change in temperature of a coolant between an inlet and an outlet of the fuel cell system, comparing the change in temperature of the coolant to a predetermined target coolant temperature, adjusting a speed of a motor of the cooling system to change a flow rate of the coolant, and driving the coolant with an adjusted flow rate through a cooling system to maintain an operating temperature of the fuel cell system. The motor is coupled to a pump of the cooling system.

A fifth aspect of the present invention relates to a cooling system for thermally managing a fuel cell system in a vehicle. The system includes a pump, a motor coupled to the pump, and a pump motor speed controller. The pump drives a coolant through the cooling system and the fuel cell system coupled to the cooling system. The pump motor speed controller is electrically coupled to the motor to drive the pump and adjusts the speed of the motor to manipulate a flow rate of the coolant and maintain an operating temperature of the fuel cell system. The system may be an apparatus or embodied within an apparatus.

In the first aspect of the present invention, drawing crosswinds into the radiator in an opposite direction may include drawing ambient air into the radiator first and then through the one or more fans second. In the first aspect of the present invention, drawing crosswinds into the radiator in an opposite direction may include drawing ambient air into the one or more fans first and then through the radiator second.

In the first aspect of the present invention, the step of operating may further include operating a second radiator, the second radiator being coupled to one or more fans. In the first aspect of the present invention, drawing crosswinds into the radiator in an opposite direction may include drawing ambient air into the radiator first, through the one or more fans second, through the one or more fans coupled to the second radiator third, and through the second radiator last.

In the first and second aspect of the present invention, the vehicle or stationary vehicle may be a train.

In the first and third aspect of the present invention, the radiator and/or the at least two radiators, the one or more fans and/or the at least two fans, and the fuel cell system may be located in a frame.

In the first, second, and third aspect of the present invention, the stationary position may include or the stationary vehicle may travel at a vehicle speed that is at, about, or lower than about 15 km/hour and/or 20 km/hour.

In the first, second, and third aspect of the present invention, the radiator and/or one or more radiators and/or at least two radiators, the one or more fans and/or the one or more adjusted fans and/or the at least two fans, and the fuel cell system may be located on the top surface and/or top-side of the vehicle and/or stationary vehicle and/or stationary train. In the first, second, and third aspect of the present invention, the radiator and/or one or more radiators and/or at least two radiators, the one or more fans and/or the one or more adjusted fans and/or the at least two fans, and the fuel cell system may be separately located on the top surface and/or top-side of the vehicle and/or stationary vehicle and/or stationary train. In the first, second, and third aspect of the present invention, the radiator and/or one or more radiators and/or at least two radiators, the one or more fans and/or the one or more adjusted fans and/or the at least two fans may be positioned adjacent to the fuel cell system by at least 0.5 inches of a separation distance. In the first, second, and third aspect of the present invention, the separation distance may range from about 0.5 inches to about 12 inches.

In the fourth aspect of the present invention, determining the change in temperature may include detecting the temperature of the coolant or calculating the change in temperature of the coolant. In the fourth aspect of the present invention, detecting the temperature of the coolant may include measuring the temperature of the coolant at the inlet of the fuel cell system with a first temperature sensor or measuring the temperature of the coolant at the outlet of the fuel cell system with a second temperature sensor.

In the fourth aspect of the present invention, the method may further include the step of detecting a pressure of the coolant. In the fourth aspect of the present invention, detecting the pressure of the coolant may include detecting the pressure of the coolant at an inlet of the pump or an outlet of the pump with a pressure sensor.

In the fourth aspect of the present invention, the method may further include the step of variably manipulating the adjusted flow rate or the temperature of the coolant through the cooling system.

In the fourth and fifth aspect of the present invention, the speed of the motor may be adjusted to and/or the pump motor speed controller may adjust the speed of the motor to at least about 2,500 RPM. In the fourth and fifth aspect of the present invention, the speed of the motor may be adjusted to and/or the pump motor speed controller may adjust the speed of the motor to between about 2,500 RPM and about 3,000 RPM.

In the fifth aspect of the present invention, the cooling system may further include a first temperature sensor to detect the temperature of the coolant at an inlet of the fuel cell system and a second temperature sensor to detect the temperature of the coolant at an outlet of the fuel cell system. In the fifth aspect of the present invention, the pump motor speed controller may be electrically coupled to both the first temperature sensor and the second temperature sensor to monitor a change in temperature between the coolant at the inlet of the fuel cell system and at the outlet of the fuel cell system. In the fifth aspect of the present invention, the cooling system may further include a coolant pressure sensor to detect the pressure of the coolant at an outlet and/or at an inlet of the pump.

In the fifth aspect of the present invention, an adjusted flow rate of the coolant through the cooling system may be configured to maintain the operating temperature of the fuel cell system.

The features illustrated or described in connection with one exemplary embodiment may be combined with any other feature or element of any other embodiment described herein. Such modifications and variations are intended to be included within the scope of the present disclosure. Further, a person skilled in the art will recognize that terms commonly known to those skilled in the art may be used interchangeably herein.

The above embodiments are described in sufficient detail to enable those skilled in the art to practice what is claimed and it is to be understood that logical, mechanical, and electrical changes may be made without departing from the spirit and scope of the claims. The detailed description is, therefore, not to be taken in a limiting sense.

As used herein, an element or step recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural of said elements or steps, unless such exclusion is explicitly stated. Furthermore, references to “one embodiment” of the presently described subject matter are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Specified numerical ranges of units, measurements, and/or values include, consist essentially or, or consist of all the numerical values, units, measurements, and/or ranges including or within those ranges and/or endpoints, whether those numerical values, units, measurements, and/or ranges are explicitly specified in the present disclosure or not.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terms “first”, “second”, “third”, and the like, as used herein do not denote any order or importance, but rather are used to distinguish one element from another. The term “or” and “and/or” is meant to be inclusive and mean either, all, or any combination of the listed items. In addition, the terms “connected” and “coupled” are not restricted to physical or mechanical connections or couplings, and can include electrical connections or couplings, whether direct or indirect. Direct connection and/or coupling can include such connections and/or couplings where no intermittent connection or component is present between two endpoints, components or items. Indirect connection and/or coupling can include where there is one or more intermittent or intervening connections and/or couplings present between respective endpoints, components or items.

Moreover, unless explicitly stated to the contrary, embodiments “comprising”, “including”, or “having” an element or a plurality of elements having a particular property may include additional such elements not having that property. The term “comprising” or “comprises” refers to a composition, compound, formulation, or method that is inclusive and does not exclude additional elements, components, and/or method steps. The term “comprising” also refers to a composition, compound, formulation, or method embodiment of the present disclosure that is inclusive and does not exclude additional elements, components, or method steps. The phrase “consisting of” or “consists of” refers to a compound, composition, formulation, or method that excludes the presence of any additional elements, components, or method steps.

The term “consisting of” also refers to a compound, composition, formulation, or method of the present disclosure that excludes the presence of any additional elements, components, or method steps. The phrase “consisting essentially of” or “consists essentially of” refers to a composition, compound, formulation, or method that is inclusive of additional elements, components, or method steps that do not materially affect the characteristic(s) of the composition, compound, formulation, or method. The phrase “consisting essentially of” also refers to a composition, compound, formulation, or method of the present disclosure that is inclusive of additional elements, components, or method steps that do not materially affect the characteristic(s) of the composition, compound, formulation, or method steps.

As used herein, the terms “may” and “may be” indicate a possibility of an occurrence within a set of circumstances; a possession of a specified property, characteristic or function; and/or qualify another verb by expressing one or more of an ability, capability, or possibility associated with the qualified verb. Accordingly, usage of “may” and “may be” indicates that a modified term is apparently appropriate, capable, or suitable for an indicated capacity, function, or usage, while taking into account that in some circumstances, the modified term may sometimes not be appropriate, capable, or suitable.

It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used individually, together, or in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the subject matter set forth herein without departing from its scope. While the dimensions and types of materials described herein are intended to define the parameters of the disclosed subject matter, they are by no means limiting and are exemplary embodiments. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the subject matter described herein should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

This written description uses examples to disclose several embodiments of the subject matter set forth herein, including the best mode, and also to enable a person of ordinary skill in the art to practice the embodiments of disclosed subject matter, including making and using the devices or systems and performing the methods. The patentable scope of the subject matter described herein is defined by the claims, and may include other examples that occur to those of ordinary skill in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.