Station and method for filling tanks of hydrogen-fueled vehicles

Abstract

A hydrogen refueling station for filling the tanks of fuel cell vehicles includes a liquid hydrogen tank that supplies liquid hydrogen to an upstream end of a filling circuit that also includes a heat exchanger. The heat exchanger exchanges heat between the liquid hydrogen stream and a heat transfer fluid stream, thereby cooling the heat transfer fluid and vaporizing the liquid hydrogen to provide a supply of high-pressure hydrogen gas for filling the hydrogen-fueled vehicle tank at the downstream end of the filling circuit. Because the liquid hydrogen is surrounded by the heat transfer fluid inside the heat exchanger, little atomization occurs.

Description

[Technical Field]

[0001] The present invention relates to a device for filling a pressurized gas tank.

[0002] Specifically, the present invention relates to a device for filling the tanks of a fuel cell electric vehicle (FCEV), the device comprising: a liquefied gas source; and a transfer circuit in downstream fluid communication with the liquefied gas source, the transfer circuit including at least one downstream end adapted and configured to be removably connected to a vehicle hydrogen tank to be filled. [Background technology]

[0003] Hydrogen gas refueling stations that use a liquid hydrogen source are known. These known devices allow for the use of refrigeration from the liquid hydrogen to generate pre-cooled pressurized hydrogen gas for rapid filling without experiencing excessive temperature rise of the gas in the tank during filling.

[0004] For example, Daney et al. proposed a conceptual refueling station that uses a vaporizer to provide ambient temperature high pressure gaseous hydrogen that is then cooled prior to being delivered to the vehicle tank: Daney, et al., "Hydrogen-fuelled vehicle fuelling station," Advances in Cryogenic Engineering, vol. 41, 1996.

[0005] Another such station, implemented in an urban bus refueling station, utilizes a vaporizer that transfers heat from the ambient air to a pumped stream of liquid hydrogen to provide a high-pressure gaseous hydrogen stream to the vehicle tank: Raman, et al. "A rapid fill hydrogen fuel station for fuel cell buses", 12th World Energy conference Hydrogen energy Progress 2, pp 1629-1642.

[0006] At atmospheric pressure, the boiling point of hydrogen is −252.8°C. Because the station disclosed in Raman et al. uses a vaporizer that exchanges heat between liquid hydrogen and ambient air, the surface temperature of the ambient air vaporizer is very low. As a result, water vapor from the ambient air condenses and freezes on the surface of the ambient air vaporizer. Also, the air surrounding the ambient air vaporizer condenses and drips onto the equipment below. This poses a risk to the equipment below. The equipment may become thermally embrittled; especially equipment made of carbon steel and plate may crack, structural beams may fail, and pipes may burst. Because oxygen condenses at a higher temperature than nitrogen, an oxygen-enriched atmosphere may be created. Of course, there are many known risks presented by an oxygen-enriched atmosphere. Furthermore, the condensed air exacerbates the cryogenic cloud around the equipment.

[0007] When the depth of frozen water on the surface of a fresh air vaporizer reaches an unsatisfactory depth, thereby reducing effective heat transfer, or even creating bridges between adjacent vanes of the fresh air vaporizer, such a vaporizer must be defrosted before further use can continue. To solve this problem, two fresh air vaporizers can be used in an alternating manner, such that one is defrosted while the other is used to vaporize liquid hydrogen. While this solves the problem, it can unsatisfactorily increase capital costs due to the need to have two fresh air vaporizers per filling circuit. For hydrogen filling stations located in areas where real estate is expensive and / or for hydrogen filling stations co-located with retail gasoline stations where the station space is leased from the retail gasoline station, capital costs are also increased because the need to have two vaporizers doubles the footprint or space occupied by the liquid vaporization portion of the station.

[0008] Because the surface temperature of the ambient air vaporizer is so low, water vapor in the ambient air also condenses in some areas surrounding the vaporizer, creating an atomized condition.

[0009] While fogging can be a nuisance for refueling stations isolated from the public (e.g., in industrial areas typically far from consumers), it is a much more serious problem for more visible refueling stations, such as retail hydrogen refueling stations, public demonstration refueling stations, and hydrogen filling stations co-located with retail gasoline stations. This is because the public may see fogging emanating from the hydrogen refueling station and mistakenly conclude that either a dangerous hydrogen leak or even a fire has occurred at the station. Thus, a false report of a hazardous leak or dangerous fire to emergency responders would require the station to be shut down and a thorough safety assessment to follow before the station can be declared safe for operation. For this reason, the use of fresh air vaporizers could significantly hinder the deployment of hydrogen refueling stations served by on-site tanks of liquid hydrogen and located in prominent areas that are visible to the public. Summary of the Invention [Means for solving the problem]

[0010] SUMMARY OF THE INVENTION It is an object of the present invention to overcome all or some of the above-mentioned disadvantages of the prior art.

[0011] A hydrogen refueling station is disclosed that includes a liquid hydrogen source adapted and configured to store liquid hydrogen, a fill circuit, and a heat exchange fluid circuit. The fill circuit has an upstream end in downstream fluid communication with a liquid hydrogen source to allow liquid hydrogen to flow from the liquid hydrogen source into the fill circuit, a downstream end adapted and configured to be removably connected to an FCEV tank for filling the FCEV tank, and a first heat exchanger disposed between the upstream and downstream ends of the fill circuit. The heat transfer circuit includes, in flow order, an upstream end in downstream fluid communication with the first heat exchanger, a second heat exchanger, a heat transfer fluid pump, and a downstream end in upstream fluid communication with the first heat exchanger, the heat transfer fluid pump adapted and configured to receive heat transfer fluid from the second heat exchanger and direct it to the first heat exchanger. The second heat exchanger is adapted and configured to warm the cooled heat transfer fluid received from the first heat exchanger. The first heat exchanger is adapted and configured to exchange heat between the heat transfer fluid flowing through the heat transfer circuit and the liquid hydrogen in the filling circuit to cool the heat transfer fluid, and is further adapted and configured to vaporize the liquid hydrogen to provide pressurized gaseous hydrogen for filling the tank, the flow of liquid hydrogen inside the first heat exchanger being surrounded by the flow of heat transfer fluid.

[0012] Also disclosed is a hydrogen refueling station including a liquid hydrogen source adapted and configured to store liquid hydrogen, first and second fill circuits, a heat transfer fluid reservoir, and first and second heat exchange fluid circuits, the first fill circuit having an upstream end in downstream fluid communication with the liquid hydrogen source to allow flow of liquid hydrogen from the liquid hydrogen source into the first fill circuit, a downstream end adapted and configured to be removably connected to a hydrogen fuel vehicle tank for filling the hydrogen fuel vehicle tank, and a first heat exchanger disposed between the upstream and downstream ends of the first fill circuit; The second filling circuit has an upstream end in downstream fluid communication with a liquid hydrogen source to permit flow of liquid hydrogen from the liquid hydrogen source into the second filling circuit, a downstream end adapted and configured to be removably connected to a hydrogen fuel vehicle tank for filling the hydrogen fuel vehicle tank, and a first heat exchanger disposed between the upstream and downstream ends of the second filling circuit, the first heat transfer circuit having, in flow order, an upstream end in downstream flow communication with the first heat exchanger of the first filling circuit, the second heat exchanger, the heat transfer fluid pump, and upstream fluid communication with the first heat exchanger of the first filling circuit. a downstream end of the second heat transfer circuit, the heat transfer fluid pump of the first heat transfer circuit adapted and configured to receive heat transfer fluid from the second heat exchanger of the first heat transfer circuit and direct it to the first heat exchanger of the first heat transfer circuit; and a second heat transfer circuit comprising, in flow order, an upstream end in downstream flow communication with the first heat exchanger of the second charge circuit, the second heat exchanger, the heat transfer fluid pump, and a downstream end in upstream fluid communication with the first heat exchanger of the second charge circuit, the heat transfer fluid pump of the second heat transfer circuit adapted and configured to receive heat transfer fluid from the second heat exchanger of the second heat transfer circuit and direct it to the first heat exchanger of the second heat transfer circuit. the second heat exchanger of the first heat transfer circuit is adapted and configured to warm the cooled heat transfer fluid received from the first heat exchanger of the first heat transfer circuit; the second heat exchanger of the second heat transfer circuit is adapted and configured to warm the cooled heat transfer fluid received from the first heat exchanger of the second heat transfer circuit; a heat transfer fluid reservoir is in fluid communication between the second heat exchanger of the first heat transfer circuit and the heat transfer fluid pump, and is in fluid communication between the second heat exchanger of the second heat transfer circuit and the heat transfer fluid pump;the first heat exchanger of the first filling circuit is adapted and configured to exchange heat between a heat transfer fluid flowing through the first heat transfer circuit and the liquid hydrogen in the first filling circuit to cool the heat transfer fluid, and is further adapted and configured to vaporize the liquid hydrogen to provide pressurized gaseous hydrogen for filling a tank of a hydrogen-fueled vehicle, the liquid hydrogen flow inside the first heat exchanger of the first filling circuit being surrounded by the heat transfer fluid flow; the first heat exchanger of the second filling circuit is adapted and configured to exchange heat between a heat transfer fluid flowing through the second heat transfer circuit and the liquid hydrogen in the second filling circuit to cool the heat transfer fluid, and is further adapted and configured to vaporize the liquid hydrogen to provide pressurized gaseous hydrogen for filling a tank of a hydrogen-fueled vehicle, the liquid hydrogen flow inside the first heat exchanger of the second filling circuit being surrounded by the heat transfer fluid flow;

[0013] Also disclosed is a method for filling a hydrogen-fueled vehicle tank with pressurized hydrogen, comprising the steps of: liquid hydrogen supplied from a liquid hydrogen source in a filling circuit removably connected at its downstream end to the tank of the hydrogen-fueled vehicle; the filling circuit having a first heat exchanger disposed therein, the first heat exchanger having a liquid hydrogen inlet, a gaseous hydrogen outlet, a heat transfer fluid inlet, and a heat transfer fluid outlet; heat transfer fluid is pumped by a heat transfer pump through a heat transfer circuit looped with the first heat exchanger, the heat transfer circuit including, in flow order from the heat transfer fluid outlet to the heat transfer fluid inlet, a second heat exchanger and a heat transfer fluid pump; heat is exchanged by the first heat exchanger between the heat transfer fluid flowing through the heat transfer fluid circuit and liquid hydrogen supplied to the filling circuit from the liquid hydrogen source, thereby vaporizing the supplied liquid hydrogen and cooling the heat transfer fluid; the supplied liquid hydrogen inside the first heat exchanger is surrounded by the heat transfer fluid. The cooled heat transfer fluid received from the first heat exchanger is heated by the second heat exchanger.The tank of the hydrogen fuel vehicle is filled with pressurized gaseous hydrogen from the downstream end of the filling circuit.

[0014] The station or method may include one or more of the following aspects: Liquid hydrogen is pumped from a source of liquid hydrogen into the filling circuit by a liquid hydrogen pump. The pressure of the pressurized gaseous hydrogen in the filling circuit downstream of the first heat exchanger is measured by a pressure sensor; and the pressure of the pressurized gaseous hydrogen is controlled by a pressure control valve based on the pressure of the pressurized gaseous hydrogen measured by the pressure sensor. a liquid hydrogen pump in downstream flow communication with the liquid hydrogen source and in upstream flow communication with the first heat exchanger, the liquid hydrogen pump adapted and configured to increase the pressure of a flow of liquid hydrogen from the liquid hydrogen source and direct the pressurized flow of liquid hydrogen towards the first heat exchanger. the filling circuit further comprises a pressure control valve and a pressure sensor downstream of the first exchanger, and the pressure control valve is adapted and configured to control the pressure of the pressurized gaseous hydrogen for filling the tank based on the pressure of the pressurized gaseous hydrogen measured by the pressure sensor. the heat transfer circuit further includes a primary line, a bypass line, a three-way flow control valve, a temperature sensor, and a downstream line in flow communication between the three-way flow control valve and the heat transfer fluid pump; the primary line extends in flow communication between the first heat exchanger and the three-way flow control valve; the bypass line branches off from the primary line and is in upstream flow communication with the three-way flow control valve; the second heat exchanger is disposed within the primary line; and the three-way flow control valve controls the flow of warmed heat transfer fluid from the primary line and the flow of unwarmed heat transfer fluid from the bypass line. and a three-way control valve for controlling the flow of the heated heat transfer fluid from the primary line and the flow of the unheated heat transfer fluid from the bypass line, combining the flow of the heated heat transfer fluid from the primary line and the flow of the unheated heat transfer fluid from the bypass line and directing the combined flow of the heat transfer fluid to the heat transfer pump; a temperature sensor is disposed in the heat transfer circuit between the three-way control valve and the first heat exchanger; and the three-way control valve controls the temperature of the heat transfer fluid between the three-way control valve and the first heat exchanger by adjusting the ratio of the flow rate of the heated heat transfer fluid to the flow rate of the unheated heat transfer fluid in the combined flow of the heat transfer fluid. The heat transfer fluid circuit further includes a blower adapted and configured to blow outside air at the second heat exchanger so as to warm the heat transfer fluid with the heat of the blown outside air. The second heat exchanger is an electric heater adapted and configured to heat a heat transfer fluid. the station includes two or more buffer vessels, a leg branching off from the filling circuit downstream of the first heat exchanger adapted and configured to direct pressurized gaseous hydrogen from the first heat exchanger to the two or more buffer vessels, a set of valves adapted and configured to allow the pressurized gaseous hydrogen to flow through the leg into one of the buffer vessels but not into the other buffer vessels, and to allow the pressurized gaseous hydrogen to flow from one of the buffer vessels back through the leg to a downstream end of the filling circuit, and the pressure control valve adapted and configured to control the pressure of the pressurized gaseous hydrogen exiting the downstream end of the filling circuit based on a pressure sensed by a pressure sensor located in the filling circuit between the leg and the downstream end of the filling circuit. the filling circuit further includes a primary line in fluid communication between the upstream and downstream ends of the filling circuit, a bypass line branching from the primary line and rejoining the primary line downstream of the first heat exchanger, a flow control valve disposed in the primary line, a flow control valve disposed in the bypass line, and a temperature sensor disposed in the filling circuit downstream of the point where the bypass line rejoins the primary line and upstream of the downstream end of the filling circuit, wherein the first heat exchanger is disposed in the primary line, the flow control valve disposed in the primary line is adapted and configured to control the flow of vaporized hydrogen through the primary line, and the flow control valve disposed in the bypass line is adapted and configured to control the flow of liquid hydrogen through the bypass line, and the flow control valve controls the flow of vaporized hydrogen and the flow of liquid hydrogen to control the temperature of the pressurized gaseous hydrogen for filling the tank based on the temperature sensed by the temperature sensor. The heat transfer circuit further includes a heat transfer reservoir in fluid communication between the second heat exchanger and the heat transfer pump, the heat transfer reservoir adapted and configured to contain a volume of heat transfer fluid. the station further includes a first liquid hydrogen pump in downstream flow communication with the liquid hydrogen source and in upstream fluid communication with the first heat exchanger of the first filling circuit, the first liquid hydrogen pump adapted and configured to increase the pressure of the flow of liquid hydrogen from the liquid hydrogen source and to direct the pressurized flow of liquid hydrogen towards the first heat exchanger of the first filling circuit; and a second liquid hydrogen pump in downstream flow communication with the liquid hydrogen source and in upstream fluid communication with the first heat exchanger of the second filling circuit, the second liquid hydrogen pump adapted and configured to increase the pressure of the flow of liquid hydrogen from the liquid hydrogen source and to direct the pressurized flow of liquid hydrogen towards the first heat exchanger of the second filling circuit. Each of the filling circuits further includes a pressure control valve and a pressure sensor downstream of the associated first exchanger, the pressure control valve adapted and configured to control the pressure of the pressurized gaseous hydrogen for filling the tank of the hydrogen-fueled vehicle based on the pressure of the pressurized gaseous hydrogen measured by the pressure sensor. each of the heat transfer circuits further includes a primary line, a bypass line, a three-way flow control valve, a temperature sensor, and a downstream line in flow communication between the three-way flow control valve and the heat transfer fluid pump; each primary line extends in flow communication between an associated first heat exchanger and the associated three-way flow control valve; each bypass line branches from the associated primary line and is in upstream flow communication with the associated three-way flow control valve; each second heat exchanger is disposed within the associated primary line; each three-way flow control valve controls the flow of warmed heat transfer fluid from the associated primary line and the flow of unwarmed heat transfer fluid from the associated bypass line; and controlling the flow of the warmed heat transfer fluid from the associated primary line and the flow of the unwarmed heat transfer fluid from the associated bypass line, combining the flow of the warmed heat transfer fluid from the associated primary line and the flow of the unwarmed heat transfer fluid from the associated bypass line and directing the combined flow of the heat transfer fluid to the associated heat transfer pump; each temperature sensor is disposed in an associated heat transfer circuit between an associated three-way flow control valve and an associated first heat exchanger; each three-way control valve controls the temperature of the heat transfer fluid between the respective three-way control valve and the associated first heat exchanger by adjusting the ratio of the flow rate of the warmed heat transfer fluid to the flow rate of the unwarmed heat transfer fluid in the combined flow of the heat transfer fluid. Each heat transfer fluid circuit further includes a blower adapted and configured to blow ambient air at an associated second heat exchanger so as to warm the heat transfer fluid with the heat of the blown ambient air. Each second heat exchanger is an electric heater adapted and configured to heat a heat transfer fluid. each filling circuit further includes: a primary line in fluid communication between its upstream end and downstream end; a bypass line branching from the associated primary line and rejoining the associated primary line downstream of the associated first heat exchanger; a flow control valve disposed in the associated primary line; a flow control valve disposed in the associated bypass line; and a temperature sensor disposed downstream of the point where the associated bypass line rejoins the associated primary line, the temperature sensor being disposed upstream of the downstream end of the temperature sensor, the associated first heat exchanger being disposed in the associated primary line; the flow control valve disposed in the associated primary line adapted and configured to control the flow of vaporized hydrogen through the associated primary line, and the flow control valve disposed in the associated bypass line adapted and configured to control the flow of liquid hydrogen through the associated bypass line, the flow control valve controlling the flow of vaporized hydrogen and the flow of liquid hydrogen to control the temperature of pressurized gaseous hydrogen for filling a tank of a hydrogen-fueled vehicle based on the temperature sensed by the temperature sensor. The downstream end includes at least two nozzles each adapted and configured to be removably connected to a hydrogen fuel vehicle tank for filling the hydrogen fuel vehicle tank.

[0015] Other features and advantages will appear from a reading of the following description, which refers to the accompanying drawings. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a schematic diagram of an embodiment of the inventive station and method of the present invention. [Figure 2] 2 is a schematic diagram of a variation of the station and method of FIG. 1; [Figure 3] 2 is a schematic diagram of a variation of the station and method of FIG. 1; [Figure 4] FIG. 4 is a schematic diagram of a combination of station and method features of FIGS. 2 and 3. [Figure 5] FIG. 5 is a schematic diagram of a variation of the station and method of FIG. 4. [Figure 6] FIG. 6 is a schematic diagram of a variation of the station and method of FIG. 5. DETAILED DESCRIPTION OF THE INVENTION

[0017] 1, liquid hydrogen from a liquid hydrogen source 1 is supplied via its upstream end to a charging circuit 2 that includes a first heat exchanger 3, a pressure control valve 5, and a second heat exchanger 15. The downstream end of the charging circuit 2 is removably connected to a tank of a hydrogen fuel cell electric vehicle (FCEV) 6. Heat transfer fluid enters a heat transfer fluid circuit 4 that includes a heat transfer fluid pump 25, a temperature sensor 27, and a liquid hydrogen pump 31.

[0018] The liquid hydrogen source optionally includes a pressure building circuit for building pressure in a headspace of the liquid hydrogen source by controlling the amount of liquid hydrogen from the liquid hydrogen source to exit the liquid hydrogen source and enter a line thermally connected to the ambient atmosphere using a flow control valve. The liquid hydrogen vaporizes in this line and is directed into the headspace. A pressure sensor measures the pressure inside the headspace. A controller is used to operate the flow control valve based on the measured headspace pressure to reach a desired pressure in the headspace.

[0019] The liquid hydrogen pump 31 is used to supply and pressurize liquid hydrogen from the liquid hydrogen source into the filling circuit. The use of the liquid hydrogen pump 31 allows liquid hydrogen to be pumped up to the supercritical pressure desired for high-pressure filling of the tanks of the hydrogen-fueled vehicle 6. For example, liquid hydrogen stored in the liquid hydrogen source 1 at a pressure of about 50 bar can easily be pumped up to a pressure of 900 bar or even higher. The characteristics and features of the particular liquid hydrogen pump 31 employed are typically driven by the desired maximum pressure to supply the tanks of the FCEV 6 and to supply the desired filling capacity of the refueling station. Preferably, each liquid hydrogen pump 31 is characterized by the following operating conditions: an available suction head of 2 to 5 psi, a nominal flow rate of 45 kg / h, a liquid hydrogen suction pressure of 100 psi, and a maximum discharge pressure of about 15,000 psi.

[0020] Liquid hydrogen supplied from a liquid hydrogen source 1 into filling circuit 2 is vaporized in first heat exchanger 3 to provide pressurized gaseous hydrogen for filling the tank of FCEV 6. First heat exchanger 3 exchanges heat between the heat transfer fluid entering heat transfer fluid circuit 4 and the liquid hydrogen entering filling circuit 2, thereby vaporizing the liquid hydrogen (producing cold hydrogen in a supercritical fluid state) and cooling the heat transfer fluid. The vaporized liquid hydrogen constitutes the pressurized gaseous hydrogen used to fill the tank of hydrogen-fueled vehicle 6. Either the driver / customer of FCEV 6 or the refueling station operator can access a nozzle (at the downstream end of filling circuit 2) conveniently located with an interface typically found at a standard gas station (i.e., gas pump) that includes an indication of the price of hydrogen, the amount of hydrogen delivered, and a start / stop button.

[0021] The cooled heat transfer fluid is warmed in the second heat exchanger 15 and pumped back to the first heat exchanger 3 using a heat transfer fluid pump 25. The second heat exchanger 15 may be an ambient air evaporator in which the cooled heat transfer fluid is warmed by heat from ambient air blown onto the ambient air evaporator by a blower. Optionally, the second heat exchanger may be an electric heater.

[0022] While any known heat transfer fluid remains in a liquid phase at nominal pressure down to at least −135° C., one non-limiting and particularly suitable example of any known heat transfer fluid is available from Eastman under the trademark Therminol VLT®. Therminol VLT® is a mixture of methylcyclohexane and trimethylpentane and has a reported liquid heat capacity ranging from 1.29 kJ / (kg·K) at −135° C. to 2.04 kJ / (kg·K) at 40° C.

[0023] The temperature of the heat transfer fluid can be controlled as follows: A controller (not shown) controls the speed of the heat transfer fluid pump 25 (e.g., by increasing or decreasing the speed of the variable frequency drive of the pump 25) based on the temperature of the heat transfer fluid sensed by the temperature sensor 29. If the temperature of the heat transfer fluid immediately upstream of the first heat exchanger 3 is unsatisfactorily high, it will impair the ability of the heat transfer fluid to warm the liquid hydrogen flowing through the first heat exchanger 3. On the other hand, if the temperature of the heat transfer fluid is too low, it may become too viscous or even freeze. The controller is typically a computer or programmable logic controller. Specifically, the temperature of the heat transfer fluid downstream of the first heat exchanger can be controlled within a certain temperature range or according to a certain temperature setpoint.

[0024] Within the first heat exchanger 3, the liquid hydrogen flow is surrounded by a heat transfer fluid flow. This prevents the outer surface temperature of the first heat exchanger 3 from reaching the very low temperatures experienced by ambient air vaporizers at conventional liquid hydrogen source hydrogen filling stations. Therefore, condensation of water vapor on the first heat exchanger 3 and the resulting frosting (and the associated defrosting problems in the prior art discussed above) are avoided. Also, condensation of water vapor in the area surrounding the first heat exchanger 3 (and the associated atomization problems in the prior art discussed above) is avoided. Typically, the first heat exchanger 3 is configured as a tube-in-tube design, with liquid hydrogen flowing through an inner tube and heat transfer fluid flowing into an outer tube. For pressures of approximately 900 bar, a tube-in-tube heat exchanger is less complex and less expensive than a shell-and-tube heat exchanger. Alternatively, the first heat exchanger can be a shell-and-tube heat exchanger in which the tube fluid is liquid hydrogen and the shell fluid is the heat transfer fluid. Types of heat exchangers other than pipe-in-pipe or shell-and-tube configurations can be used for the first heat exchanger 3 and can be used with the present invention as long as the liquid hydrogen is surrounded by a heat transfer fluid and / or the exterior surface temperature of the first heat exchanger 3 does not reach the very low temperatures of conventional ambient air vaporizers, thereby avoiding atomization and frosting. Some portions of the charge circuit upstream of the first heat exchanger can be vacuum jacketed to prevent frosting and atomization problems.

[0025] The pressure of the hydrogen used to fill the tank of the FCEV 6 may be controlled by a pressure control valve 5. The particular manner in which the tank is filled is not limited, but typically the tank is filled in accordance with a standard filling method, such as Society of Automotive Engineers (SAE) standard J2601.

[0026] As best shown in FIG. 2, the hydrogen filling station may also include one or more buffer vessels 35 downstream of the first heat exchanger for containing high-pressure hydrogen. Each of the buffer vessels may include a pressure-building circuit to maintain a desired pressure therein. Vaporized hydrogen is supplied to the buffer vessels via an additional leg 37 from the filling circuit 2. The pressure control valve 5 may be used to fill the tank of a hydrogen-fueled vehicle using the filling algorithm discussed above. As in FIG. 1, liquid hydrogen is pumped to high pressure by the liquid hydrogen pump 31 and heated by the heat transfer fluid in the first heat exchanger 3. The isolation valve 48 is closed, the isolation valve 46 is open, and one or more of the isolation valves 50 are open. Instead of being supplied directly to the FCEV, cold supercritical hydrogen is used to fill one or more of the buffer vessels 35. Optionally, one of the buffer vessels 35 is at a medium pressure while another is at a high pressure. By selecting to open or close the shut-off valve 50, the high pressure buffer vessels 35 can be filled first, and the medium pressure buffer vessels 35 can be filled second. The liquid hydrogen pump 31 does not need to run continuously unless one or more of the buffer vessels 35 is at an undesirably low pressure. If the buffer vessels 35 are full, the tanks of the FCEV 6 can be filled with hydrogen stored in the buffer vessels 35 in a cascade fill, where the medium pressure buffer vessel 35 is pressure equalized with the tank of the FCEV 6, and then the high pressure buffer vessel 35 is pressure equalized with the tank, as is known in the art.

[0027] As best shown in FIG. 3 , the second heat exchanger 15 may be an ambient air evaporator, the charging circuit 2 may also include an optional cooler 7 and a pressure sensor 9 and a temperature sensor 11, and the heat transfer fluid circuit 4 may include a heat transfer fluid reservoir 23 and a temperature sensor 27. The FCEV's tank may be filled using the pressure control valve 5 as described above based on the pressure and temperature sensed by the pressure sensor 9 and the temperature sensor 11. The heat transfer fluid circuit 4 includes a primary line 16 in which the second heat exchanger 15 is disposed. Cooled heat transfer fluid is warmed by heat from ambient air blown onto the second heat exchanger 15 by a blower 19. Optionally, there is also a bypass line 17 branching off from the primary line 16 so that a portion of the cooled heat transfer fluid is not warmed in the second heat exchanger 15. In such an optional case, the warmed heat transfer fluid in the primary line 16 is combined with the unwarmed heat transfer fluid in the bypass line 17 using a three-way control valve 21. Because the temperature of the outside air blown by blower 19 varies with the time of year, three-way control valve 21 can be controlled according to a control scheme that varies with the season. For example, in the northern winter, the entire heat transfer fluid flow can be passed through primary line 16 and heated in second heat exchanger 15, while in the summer, some or all of the heat transfer fluid flow can be passed through bypass line 17 to produce cooler heat transfer fluid for storage in heat transfer fluid reservoir 23. This is useful during particularly hot summer weather when heat leaks impair the ability to maintain the heat transfer fluid below a maximum predetermined temperature.

[0028] The temperature of the combined flow of heat transfer fluid from the three-way control valve 21 may alternatively be controlled in the following manner: A controller (which may be the same as or different from the controller used to control the temperature of the heat transfer fluid downstream of the first heat exchanger 3) controls the operation of the three-way control valve to achieve a ratio between the flow of warmed heat transfer fluid in the primary line and the flow of unwarmed heat transfer fluid in the bypass line based on temperatures measured by temperature sensors in the heat transfer circuits.

[0029] Pressure sensor 9 and temperature sensor 11 may be used to input the pressure and temperature of the hydrogen delivered to the FCEV tank as variables into the filling algorithm as described above. In particular, the filling algorithm complies with SAE standard J2601.

[0030] As best shown in FIG. 4, features of the embodiments of FIGS. 2 and 3 can be combined.

[0031] As best shown in FIG. 5 , the charging circuit includes a primary line 39 and a bypass line 41 branching off from the primary line. A portion of the liquid hydrogen fed to primary line 39 is vaporized in first heat exchanger 3, while a portion of the liquid hydrogen fed to bypass line 41 is not vaporized. The two streams of hydrogen are combined at point 42 downstream of first heat exchanger 3 to provide pressurized gaseous hydrogen. The temperature of the pressurized gaseous hydrogen can be controlled by controlling the flow of liquid hydrogen into primary line 39 and bypass line 41 with temperature control valves 43, 45. Temperature control valves 43, 45 can be controlled by a controller (not shown, but some examples include a computer or programmable logic controller that may be the same as or different from the controller controlling operation of three-way control valve 21 and / or the liquid hydrogen pump variable frequency drive) based on the temperature measured by temperature sensor 11. Those skilled in the art will recognize that if the temperature sensed by the temperature sensor is too low (high), the flow of liquid hydrogen to primary line 39 can be increased (decreased), and the flow of liquid hydrogen to bypass line 41 can be reduced (increased) by a corresponding amount. Thus, control of the temperature of the pressurized gaseous hydrogen can be performed without optional cooler 7, or optional cooler 7 can provide only supplemental cooling. In this embodiment, the flow of gaseous hydrogen to the FCEV tank is controlled by pressure control valve 5, optionally based on the pressure and temperature sensed by pressure sensor 9 and temperature sensor 11, as described above. If the FCEV tank is not being filled with hydrogen from buffer vessel 35, isolation valve 50 is closed, and the two streams of hydrogen are combined at point 42 downstream of first heat exchanger 3 to provide pressurized gaseous hydrogen for filling the FCEV tank. If one of the buffer vessels 35 is being used to fill an FCEV tank, one of the isolation valves 50 is closed, one of the isolation valves 50 is opened, and the flow of hydrogen from one of the buffer vessels 35 is combined with the flow of liquid hydrogen from the bypass line 41 at point 42 downstream of the first heat exchanger 3. During such filling, the pump 31 may continue to run or may optionally be turned off.Whether the vaporized hydrogen is obtained directly from the primary line 39 or from one of the buffer vessels 35, the temperature of the pressurized gaseous hydrogen can be controlled by controlling the flow of liquid hydrogen in the primary and bypass lines with temperature control valves 43, 45. The temperature control valves 43, 45 can be controlled by a controller (some examples, not shown, include a computer or a programmable logic controller, which may be the same as or different from controller 29) based on the temperature measured by a temperature sensor. Those skilled in the art will recognize that if the temperature sensed by the temperature sensor is too low (high), the flow of liquid hydrogen to the primary line 39 can be increased (decreased), and the flow of liquid hydrogen to the bypass line 41 can be decreased (increased) by a corresponding amount. Thus, control of the temperature of the pressurized gaseous hydrogen can be performed without the optional chiller, or the optional chiller can provide only supplemental cooling. In this embodiment, the flow of gaseous hydrogen to the FCEV tank is controlled by the pressure control valve based on the pressure sensed by the pressure sensor.

[0032] In a variation of the embodiment of Figure 5, and as best shown in Figure 6, the station may have two filling circuits 4', 4". This allows liquid hydrogen from the liquid hydrogen source 1 to be supplied to either of the liquid hydrogen pumps 31, and compressed liquid hydrogen can be supplied from the liquid hydrogen pump to either of the two filling circuits 4', 4". Although not shown, a single set of buffer vessels 35 may be shared with each of the filling circuits 4', 4", allowing the size of the buffer vessels to be optimized, thereby reducing capital costs.

[0033] It should be noted that in each of the foregoing embodiments, the downstream end may include at least two nozzles, each adapted and configured to be removably connected to a tank of an FCEV for filling the tank of the FCEV, although nozzles of any known configuration may be used, and typically the nozzles are part of a hydrogen dispenser available from Tatsuno Corporation for use in retail hydrogen refueling stations.

[0034] Regardless of the particular embodiment, the refueling station can be located anywhere an FCEV tank requires refueling, but is particularly useful when located at a retail fuel station equipped with a hydrogen dispenser for use by FCEV drivers who do not necessarily have any training in handling and dispensing high-pressure hydrogen. In a preferred filling sequence, after the nozzle is hermetically connected to the FCEV tank, gaseous hydrogen is first dispensed into the tank from the lowest-pressure buffer vessel (which is at a higher pressure than the hydrogen pressure in the tank) to reduce the effects of the Joule-Thomson effect. The specific manner in which filling is performed is governed by a filling algorithm (e.g., one conforming to the SAE J2601 standard). The pressure of the gaseous hydrogen from the nozzle is controlled by a pressure control valve based on the gaseous hydrogen pressure measured by a pressure sensor in the nozzle or in the tank. Once the lower-pressure buffer vessel and the tank are approximately pressure-equalized, gaseous hydrogen is instead dispensed into the tank from the high-pressure buffer vessel. This continues until the algorithm indicates that filling is complete. Before another FCEV tank is filled, liquid hydrogen is pumped from a liquid hydrogen source to a first heat exchanger, and the resulting pressurized gaseous hydrogen is used to replenish the buffer vessel.

[0035] The present invention offers several advantages.

[0036] The vaporizers used in the present invention do not need to be very tall, and in fact can remain less than 10' in height. This is important because in urban areas, the presence of overhead power lines, telephone lines, or trees limits the vertical space that can be occupied by a conventional fresh air vaporizer. In contrast to the vaporizers used in the present invention, conventional fresh air vaporizers often exceed 10' in height.

[0037] Compared to ambient air vaporizers, the vaporizer used in the present invention allows for more precise control of the hydrogen outlet temperature at the dispenser, which is necessary to meet the stringent temperature control profiles required by many hydrogen filling protocols, such as SAE J2601. Conventional ambient air vaporizers generally exchange heat with liquefied cryogenic gas in a passive manner, resulting in a highly dependent temperature on the ambient air. In the present invention, the temperature of the heat transfer fluid exiting the second heat exchanger can be precisely controlled through precise control of the blower speed or power supplied to the heater. This, in turn, allows for more precise control of the vaporized hydrogen exiting the first heat exchanger after exchanging heat with the temperature-controlled heat transfer fluid.

[0038] While the present invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and broad scope of the appended claims. The present invention may suitably comprise, consist of, or consist essentially of disclosed elements. The present invention may also be practiced without elements that are not disclosed. Furthermore, where language is present that refers to an order, such as first and second, this should be understood in an illustrative sense and not in a limiting sense. For example, one skilled in the art will recognize that some steps may be combined into a single step.

[0039] The singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

[0040] "Comprising" in the claims is an open-ended transitional term meaning that the subsequently identified claim elements are a non-exclusive list: that is, anything else may additionally be included and remain within the scope of "comprising." "Comprising" is defined herein as necessarily including the more restrictive transitional terms "consisting essentially of" and "consisting of;" thus, "comprising" may be replaced by "consisting essentially of" or "consisting of" and remain within the expressly defined scope of "comprising."

[0041] "Providing" in the claims is defined to mean "furnishing," "supplying," "making available," or "preparing something." Steps may be performed by any entity without claim language to the contrary.

[0042] "Optional" or "optionally" means that the subsequently described event or circumstance may or may not occur. This specification includes instances where the event or circumstance occurs and instances where the event or circumstance does not occur.

[0043] Ranges may be expressed herein as from about one particular value and / or to another particular value. When such a range is expressed, it should be understood that another embodiment is from the one particular value and / or to the other particular value, along with all combinations within said ranges.

[0044] All references identified herein are incorporated by reference in their entirety into this application, as are the specific information for which each is cited. [Explanation of symbols]

[0045] 1. Liquid hydrogen source 2 Filling circuit 3. First heat exchanger 4 Heat transfer fluid circuit 5. Pressure control valve 6 vehicles 7 Optional Cooler 9. Pressure Sensor 10. Shut-off valve 11 Temperature Sensor 15 Second heat exchanger 16 Heat transfer fluid circuit primary line 17 Heat transfer fluid circuit bypass line 19 Blower 21 Three-way control valve 23 Heat Transfer Fluid Reservoir 25 Heat Transfer Fluid Pump 27 Temperature Sensor 29 Temperature Sensor 31 Liquid hydrogen pump 33 Valve 35 Buffer container 37 Legs 39 Filling circuit primary line 41 Filling circuit bypass line 42 Connection point 43 Temperature control valve 45 Temperature control valve 46 Shut-off valve 48 Shut-off valve 50 Shut-off valve The following is a summary of the claims as originally filed: [1] A hydrogen refueling station adapted and configured to store liquid hydrogen, comprising a liquid hydrogen source, a filling circuit, and a heat exchange fluid circuit, the filling circuit includes an upstream end in downstream fluid communication with the liquid hydrogen source to permit flow of liquid hydrogen from the source into the filling circuit, a downstream end adapted and configured to be removably connected to a hydrogen fuel vehicle tank for filling the hydrogen fuel vehicle tank, and a first heat exchanger disposed between the upstream end and the downstream end of the filling circuit; the heat transfer circuit including, in flow order, an upstream end in downstream flow communication with the first heat exchanger, a second heat exchanger, a heat transfer fluid pump, and a downstream end in upstream flow communication with the first heat exchanger, the heat transfer fluid pump adapted and configured to receive heat transfer fluid from the second heat exchanger and direct it to the first heat exchanger; the second heat exchanger adapted and configured to warm the cooled heat transfer fluid received from the first heat exchanger; the first heat exchanger is adapted and configured to exchange heat between the heat transfer fluid flowing through the heat transfer circuit and the liquid hydrogen in the filling circuit to cool the heat transfer fluid, and is further adapted and configured to vaporize the liquid hydrogen to provide the pressurized gaseous hydrogen for filling the tank, the flow of liquid hydrogen inside the first heat exchanger being surrounded by the flow of the heat transfer fluid. [2] The station of [1], further comprising a liquid hydrogen pump in downstream flow communication with the liquid hydrogen source and in upstream flow communication with the first heat exchanger, the liquid hydrogen pump adapted and configured to increase the pressure of the flow of liquid hydrogen from the liquid hydrogen source and to direct the pressurized flow of liquid hydrogen toward the first heat exchanger. [3] The station described in [1], wherein the filling circuit further includes a pressure control valve and a pressure sensor downstream of the first exchanger, and the pressure control valve is adapted and configured to control the pressure of the pressurized gaseous hydrogen for filling the tank based on the pressure of the pressurized gaseous hydrogen measured by the pressure sensor. [4] The heat transfer circuit further includes a primary line, a bypass line, a three-way flow control valve, a temperature sensor, and a downstream line in flow communication between the three-way flow control valve and the heat transfer fluid pump; the primary line extends in flow communication between the first heat exchanger and the three-way flow control valve; the bypass line branches off from the primary line and is in upstream flow communication with the three-way flow control valve; the second heat exchanger is disposed within the primary line; the three-way flow control valve controls the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, combines the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, and directs the combined flow of heat transfer fluid to a heat transfer pump; the temperature sensor is disposed in the heat transfer circuit between the three-way flow control valve and the first heat exchanger; The station described in [1], wherein the three-way control valve controls the temperature of the heat transfer fluid between the three-way control valve and the first heat exchanger by adjusting the ratio of the flow rate of the warmed heat transfer fluid to the flow rate of the unwarmed heat transfer fluid within the combined flow of heat transfer fluid. [5] The station described in [1], wherein the heat transfer fluid circuit further includes a blower adapted and configured to blow outside air at the second heat exchanger so as to warm the heat transfer fluid with the heat of the blown outside air. [6] The station of [1], wherein the second heat exchanger is an electric heater adapted and configured to heat the heat transfer fluid. [7] The station of [1], further comprising two or more buffer vessels, a leg branching off from the charging circuit downstream of the first heat exchanger adapted and configured to direct the pressurized gaseous hydrogen from the first heat exchanger to the two or more buffer vessels, a set of valves, and a pressure control valve; the set of valves is adapted and configured to allow the pressurized gaseous hydrogen to flow through the leg into one of the buffer vessels but not into the other of the buffer vessels, and to allow the pressurized gaseous hydrogen to flow from one of the buffer vessels back through the leg to the downstream end of the filling circuit; the pressure control valve is adapted and configured to control the pressure of the pressurized gaseous hydrogen flowing out of the downstream end of the filling circuit based on a pressure sensed by a pressure sensor disposed in the filling circuit between the leg and the downstream end of the filling circuit. [8] The charging circuit further includes a primary line in fluid communication between the upstream end and the downstream end of the charging circuit, a bypass line branching from the primary line and rejoining the primary line downstream of the first heat exchanger, a flow control valve disposed in the primary line, a flow control valve disposed in the bypass line, and a temperature sensor disposed in the charging circuit downstream of the point where the bypass line rejoins the primary line and upstream of the downstream end of the charging circuit; the first heat exchanger is disposed within the primary line; the flow control valve disposed within the primary line is adapted and configured to control the flow of vaporized hydrogen through the primary line; the flow control valve disposed in the bypass line is adapted and configured to control the flow of liquid hydrogen through the bypass line; The station described in [1], wherein the flow control valve controls the flow of vaporized hydrogen and the flow of liquid hydrogen to control the temperature of the pressurized gaseous hydrogen for filling the tank based on the temperature sensed by the temperature sensor. [9] The station of [1], wherein the heat transfer circuit further includes a heat transfer reservoir in fluid communication between the second heat exchanger and the heat transfer pump, the heat transfer reservoir adapted and configured to contain a volume of the heat transfer fluid.

[10] A hydrogen refueling station including a liquid hydrogen source adapted and configured to store liquid hydrogen, first and second filling circuits, a heat transfer fluid reservoir, and first and second heat exchange fluid circuits, the first filling circuit includes an upstream end in downstream fluid communication with the liquid hydrogen source to permit flow of liquid hydrogen from the source into the first filling circuit, a downstream end adapted and configured to be removably connected to a hydrogen fuel vehicle tank for filling the hydrogen fuel vehicle tank, and a first heat exchanger disposed between the upstream end and the downstream end of the first filling circuit; the second filling circuit includes an upstream end in downstream fluid communication with the liquid hydrogen source to permit flow of liquid hydrogen from the source into the second filling circuit, a downstream end adapted and configured to be removably connected to a hydrogen fuel vehicle tank for filling the hydrogen fuel vehicle tank, and a first heat exchanger disposed between the upstream end and the downstream end of the second filling circuit; the first heat transfer circuit including, in flow order, an upstream end in downstream flow communication with the first heat exchanger of the first charge circuit, a second heat exchanger, a heat transfer fluid pump, and a downstream end in upstream flow communication with the first heat exchanger of the first charge circuit; the heat transfer fluid pump of the first heat transfer circuit is adapted and configured to receive the heat transfer fluid from the second heat exchanger of the first heat transfer circuit and direct it to the first heat exchanger of the first fill circuit; the second heat transfer circuit including, in flow order, an upstream end in downstream fluid communication with the first heat exchanger of the second charge circuit, a second heat exchanger, a heat transfer fluid pump, and a downstream end in upstream fluid communication with the first heat exchanger of the second charge circuit; the heat transfer fluid pump of the second heat transfer circuit adapted and configured to receive heat transfer fluid from the second heat exchanger of the second heat transfer circuit and direct it to the first heat exchanger of the second charge circuit; the second heat exchanger of the first heat transfer circuit adapted and configured to warm cooled heat transfer fluid received from the first heat exchanger of the first heat transfer circuit; the second heat exchanger of the second heat transfer circuit adapted and configured to warm cooled heat transfer fluid received from the first heat exchanger of the second heat transfer circuit; the heat transfer fluid reservoir is in fluid communication between the second heat exchanger of the first heat transfer circuit and a heat transfer fluid pump and in fluid communication between the second heat exchanger of the second heat transfer circuit and the heat transfer fluid pump; the first heat exchanger of the first filling circuit is adapted and configured to exchange heat between the heat transfer fluid flowing through the first heat transfer circuit and liquid hydrogen in the first filling circuit to cool the heat transfer fluid, and is further adapted and configured to vaporize the liquid hydrogen to provide the pressurized gaseous hydrogen for filling a tank of a hydrogen-fueled vehicle, the flow of liquid hydrogen inside the first heat exchanger of the first filling circuit being surrounded by the flow of the heat transfer fluid; the first heat exchanger of the second filling circuit is adapted and configured to exchange heat between the heat transfer fluid flowing through the second heat transfer circuit and the liquid hydrogen in the second filling circuit to cool the heat transfer fluid, and is further adapted and configured to vaporize the liquid hydrogen to provide the pressurized gaseous hydrogen for filling a tank of a hydrogen-fueled vehicle, the flow of liquid hydrogen inside the first heat exchanger of the second filling circuit being surrounded by the flow of the heat transfer fluid.

[11] a first liquid hydrogen pump in downstream flow communication with the liquid hydrogen source and in upstream flow communication with the first heat exchanger of the first filling circuit, the first liquid hydrogen pump adapted and configured to increase the pressure of the flow of liquid hydrogen from the liquid hydrogen source and direct the pressurized flow of liquid hydrogen toward the first heat exchanger of the first filling circuit; and

[10] The station described in

[10] , further comprising a second liquid hydrogen pump in downstream flow communication with the liquid hydrogen source and in upstream flow communication with the first heat exchanger of the second filling circuit, the second liquid hydrogen pump adapted and configured to increase the pressure of the flow of liquid hydrogen from the liquid hydrogen source and to direct the pressurized flow of liquid hydrogen towards the first heat exchanger of the second filling circuit.

[12] The station described in

[10] , wherein each of the filling circuits further includes a pressure control valve and a pressure sensor downstream of the associated first exchanger, the pressure control valve adapted and configured to control the pressure of the pressurized gaseous hydrogen for filling a tank of a hydrogen-fueled vehicle based on the pressure of the pressurized gaseous hydrogen measured by the pressure sensor.

[13] Each of the heat transfer circuits further includes a primary line, a bypass line, a three-way flow control valve, a temperature sensor, and a downstream line in flow communication between the three-way flow control valve and the heat transfer fluid pump; each primary line extending in flow communication between said associated first heat exchanger and said associated three-way flow control valve; each of said bypass lines branches off from an associated primary line and is in upstream flow communication with said associated three-way flow control valve; each second heat exchanger disposed within said associated primary line; each three-way flow control valve controls the flow of warmed heat transfer fluid from its associated primary line and the flow of unwarmed heat transfer fluid from its associated bypass line, combines the flow of warmed heat transfer fluid from its associated primary line and the flow of unwarmed heat transfer fluid from its associated bypass line, and directs the combined flow of heat transfer fluid to its associated heat transfer pump; each temperature sensor disposed in said associated heat transfer circuit between said associated three-way flow control valve and said associated first heat exchanger;

[10] The station described in

[10] , wherein each three-way control valve controls the temperature of the heat transfer fluid between the respective three-way control valve and the associated first heat exchanger by adjusting the ratio of the flow rate of the warmed heat transfer fluid to the flow rate of the unwarmed heat transfer fluid within the combined flow of the heat transfer fluid.

[14] The station described in

[10] , wherein each heat transfer fluid circuit further includes a blower adapted and configured to blow outside air at the associated second heat exchanger so as to warm the heat transfer fluid with heat from the blown outside air.

[15] The station of

[10] , wherein each second heat exchanger is an electric heater adapted and configured to heat the heat transfer fluid.

[16] Each fill circuit further comprises: a primary line in fluid communication between its upstream end and its downstream end; a bypass line branching off from said associated primary line and rejoining said associated primary line downstream of said associated first heat exchanger; a flow control valve disposed within said associated primary line; a flow control valve disposed in the associated bypass line; and a temperature sensor located downstream of a point where said associated bypass line rejoins said associated primary line, said temperature sensor located upstream of said associated downstream end of said temperature sensor; said associated first heat exchanger being disposed within said associated primary line; the flow control valve disposed within the associated primary line is adapted and configured to control the flow of vaporized hydrogen through the associated primary line; the flow control valve disposed in the associated bypass line is adapted and configured to control the flow of liquid hydrogen through the associated bypass line;

[10] The station described in

[10] , wherein the flow control valve controls the flow of vaporized hydrogen and the flow of liquid hydrogen to control the temperature of the pressurized gaseous hydrogen for filling a tank of a hydrogen-fueled vehicle based on the temperature sensed by the temperature sensor.

[17] A method of filling a tank of a fuel cell vehicle with pressurized hydrogen, said method comprising: supplying liquid hydrogen from a source of liquid hydrogen to a filling circuit having a downstream end removably connected to the tank, the filling circuit having a first heat exchanger disposed therein, the first heat exchanger having a liquid hydrogen inlet, a gaseous hydrogen outlet, a heat transfer fluid inlet, and a heat transfer fluid outlet; pumping the heat transfer fluid with a heat transfer pump through a heat transfer circuit looped with the first heat exchanger, the heat transfer circuit including, in flow order from the heat transfer fluid outlet to the heat transfer fluid inlet, a second heat exchanger and a heat transfer fluid pump; exchanging heat between the heat transfer fluid flowing through the heat transfer fluid circuit and the liquid hydrogen supplied from the source to the charging circuit by the first heat exchanger, thereby vaporizing the supplied liquid hydrogen and cooling the heat transfer fluid, the supplied liquid hydrogen inside the first heat exchanger being surrounded by the heat transfer fluid; heating the cooled heat transfer fluid received from the first heat exchanger with the second heat exchanger; and The method includes filling a tank of a hydrogen fuel vehicle with said pressurized gaseous hydrogen from said downstream end of said filling circuit.

[18] The method of

[17] , further comprising pumping the liquid hydrogen from the source into the filling circuit with a liquid hydrogen pump.

[19] measuring the pressure of the pressurized gaseous hydrogen in the charging circuit downstream of the first heat exchanger with a pressure sensor; and The method according to

[17] , further comprising the step of controlling the pressure of the pressurized gaseous hydrogen by a pressure control valve based on the pressure of the pressurized gaseous hydrogen measured by the pressure sensor.

[20] The heat transfer circuit further includes a primary line, a bypass line, a three-way flow control valve, a temperature sensor, and a downstream line in flow communication between the three-way flow control valve and the heat transfer fluid pump; the primary line extends in flow communication between the first heat exchanger and the three-way flow control valve; the bypass line branches off from the primary line and is in upstream flow communication with the three-way flow control valve; the second heat exchanger is disposed within the primary line; the three-way flow control valve controls the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, combines the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, and directs the combined flow of heat transfer fluid to a heat transfer pump; the temperature sensor is disposed in the heat transfer circuit between the three-way flow control valve and the first heat exchanger;

[17] The method of

[17] , wherein the three-way control valve controls the temperature of the heat transfer fluid between the three-way control valve and the first heat exchanger by adjusting the ratio of the flow rate of the warmed heat transfer fluid to the flow rate of the unwarmed heat transfer fluid within the combined flow of heat transfer fluid.

[21] The method according to

[17] , wherein the heat transfer fluid circuit further includes a blower adapted and configured to blow outside air at the second heat exchanger so as to warm the heat transfer fluid with heat from the blown outside air.

[22] The method of

[17] , wherein the second heat exchanger is an electric heater adapted and configured to heat the heat transfer fluid.

[23] The method of

[17] , further comprising two or more buffer vessels, a leg branching off from the charging circuit downstream of the first heat exchanger adapted and configured to direct the pressurized gaseous hydrogen from the first heat exchanger to the two or more buffer vessels, a set of valves, and a pressure control valve; the set of valves is adapted and configured to allow the pressurized gaseous hydrogen to flow through the leg into one of the buffer vessels but not into the other of the buffer vessels, and to allow the pressurized gaseous hydrogen to flow from one of the buffer vessels back through the leg to the downstream end of the filling circuit; The pressure control valve is adapted and configured to control the pressure of the pressurized gaseous hydrogen exiting the downstream end of the filling circuit based on a pressure sensed by a pressure sensor disposed in the filling circuit between the leg and the downstream end of the filling circuit.

[24] The charging circuit further includes a primary line in fluid communication between the upstream end and the downstream end of the charging circuit, a bypass line branching from the primary line and rejoining the primary line downstream of the first heat exchanger, a flow control valve disposed in the primary line, a flow control valve disposed in the bypass line, and a temperature sensor disposed in the charging circuit downstream of the point where the bypass line rejoins the primary line and upstream of the downstream end of the charging circuit; the first heat exchanger is disposed within the primary line; the flow control valve disposed within the primary line is adapted and configured to control the flow of vaporized hydrogen through the primary line; the flow control valve disposed in the bypass line is adapted and configured to control the flow of liquid hydrogen through the bypass line;

[17] The method of

[17] , wherein the flow control valve controls the flow of the vaporized hydrogen and liquid hydrogen to control the temperature of the pressurized gaseous hydrogen for filling the tank based on the temperature sensed by the temperature sensor.

[25] The method of

[17] , wherein the heat transfer circuit further includes a heat transfer reservoir in fluid communication between the second heat exchanger and the heat transfer pump, the heat transfer reservoir adapted and configured to contain a volume of the heat transfer fluid.

[26] A method of filling a tank of a fuel cell vehicle with pressurized hydrogen, said method comprising: supplying liquid hydrogen from a source of liquid hydrogen to a filling circuit having a downstream end removably connected to a tank of a hydrogen-fueled vehicle, the filling circuit having a first heat exchanger disposed therein, the first heat exchanger having a liquid hydrogen inlet, a gaseous hydrogen outlet, a heat transfer fluid inlet, and a heat transfer fluid outlet; pumping the heat transfer fluid with a heat transfer pump through a heat transfer circuit looped with the first heat exchanger, the heat transfer circuit including, in flow order from the heat transfer fluid outlet to the heat transfer fluid inlet, a second heat exchanger and a heat transfer fluid pump; exchanging heat between the heat transfer fluid flowing through the heat transfer fluid circuit and the liquid hydrogen supplied from the source to the charging circuit in a first heat exchanger, thereby vaporizing the supplied liquid hydrogen and cooling the heat transfer fluid, the supplied liquid hydrogen inside the first heat exchanger being surrounded by the heat transfer fluid; heating the cooled heat transfer fluid received from the first heat exchanger with the second heat exchanger; directing the vaporized liquid hydrogen into one or more buffer vessels; and filling a tank of a hydrogen fuel vehicle with said pressurized gaseous hydrogen from said one or more buffer vessels.

[27] The method of

[26] , further comprising pumping the liquid hydrogen from the source into the filling circuit with a liquid hydrogen pump.

[28] measuring the pressure of the pressurized gaseous hydrogen in the charging circuit downstream of the first heat exchanger with a pressure sensor; and The method according to

[26] , further comprising the step of controlling the pressure of the pressurized gaseous hydrogen by a pressure control valve based on the pressure of the pressurized gaseous hydrogen measured by the pressure sensor.

[29] The heat transfer circuit further includes a primary line, a bypass line, a three-way flow control valve, a temperature sensor, and a downstream line in flow communication between the three-way flow control valve and the heat transfer fluid pump; the primary line extends in flow communication between the first heat exchanger and the three-way flow control valve; the bypass line branches off from the primary line and is in upstream flow communication with the three-way flow control valve; the second heat exchanger is disposed within the primary line; the three-way flow control valve controls the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, combines the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, and directs the combined flow of heat transfer fluid to a heat transfer pump; the temperature sensor is disposed in the heat transfer circuit between the three-way flow control valve and the first heat exchanger; and

[26] The method of

[26] , wherein the three-way control valve controls the temperature of the heat transfer fluid between the three-way control valve and the first heat exchanger by adjusting the ratio of the flow rate of the warmed heat transfer fluid to the flow rate of the unwarmed heat transfer fluid within the combined flow of heat transfer fluid.

[30] The method of

[26] , wherein the heat transfer fluid circuit further includes a blower adapted and configured to blow outside air at the second heat exchanger so as to warm the heat transfer fluid with heat from the blown outside air.

[31] The method of

[26] , wherein the second heat exchanger is an electric heater adapted and configured to heat the heat transfer fluid.

[32] The one or more buffer vessels include two or more buffer vessels and a leg branching off from the charging circuit downstream of the first heat exchanger adapted and configured to direct the pressurized gaseous hydrogen from the first heat exchanger to the one or more buffer vessels;

[26] The method of

[26] , wherein a set of valves is adapted and configured to allow the pressurized gaseous hydrogen to flow through the leg into one of the two or more buffer vessels but not into the other vessels of the two or more buffer vessels, and to allow the pressurized gaseous hydrogen to flow from one of the two or more buffer vessels back through the leg to the downstream end of the charging circuit, and further adapted and configured to control, by using the pressure control valve, a pressure of the pressurized gaseous hydrogen exiting the downstream end of the charging circuit based on a pressure sensed by a pressure sensor located in the charging circuit between the leg and the downstream end of the charging circuit.

[33] The charging circuit further includes a primary line in fluid communication between the upstream end and the downstream end of the charging circuit, a bypass line branching from the primary line and rejoining the primary line downstream of the first heat exchanger, a flow control valve disposed in the primary line, a flow control valve disposed in the bypass line, and a temperature sensor disposed in the charging circuit downstream of the point where the bypass line rejoins the primary line and upstream of the downstream end of the charging circuit; the first heat exchanger is disposed within the primary line; the flow control valve disposed within the primary line is adapted and configured to control the flow of vaporized hydrogen through the primary line; the flow control valve disposed in the bypass line is adapted and configured to control the flow of liquid hydrogen through the bypass line;

[26] The method of

[26] , wherein the flow control valve controls the flow of the vaporized hydrogen and liquid hydrogen to control the temperature of the pressurized gaseous hydrogen for filling the tank based on the temperature sensed by the temperature sensor.

[34] The method of

[26] , wherein the heat transfer circuit further includes a heat transfer reservoir in fluid communication between the second heat exchanger and the heat transfer pump, the heat transfer reservoir adapted and configured to contain a volume of the heat transfer fluid.

Claims

1. 1. A hydrogen refueling station comprising a liquid hydrogen source adapted and configured to store liquid hydrogen, a filling circuit, and a heat transfer fluid circuit, the filling circuit comprises an upstream end in downstream fluid communication with the liquid hydrogen source to permit the flow of liquid hydrogen from the liquid hydrogen source into the filling circuit, a downstream end adapted and configured to be removably connected to a hydrogen fuel vehicle tank for filling the hydrogen fuel vehicle tank, and a first heat exchanger disposed between the upstream end and the downstream end of the filling circuit; the heat transfer fluid circuit includes, in flow order, an upstream end in downstream flow communication with the first heat exchanger, a second heat exchanger, a heat transfer fluid pump, and a downstream end in upstream flow communication with the first heat exchanger, the heat transfer fluid pump adapted and configured to receive heat transfer fluid from the second heat exchanger and direct it to the first heat exchanger; the second heat exchanger is adapted and configured to warm the cooled heat transfer fluid received from the first heat exchanger; the first heat exchanger is adapted and configured to exchange heat between the heat transfer fluid flowing through the heat transfer fluid circuit and the liquid hydrogen in the filling circuit to cool the heat transfer fluid, and is further adapted and configured to vaporize the liquid hydrogen to provide pressurized gaseous hydrogen for filling the tank, the liquid hydrogen flow inside the first heat exchanger being surrounded by the heat transfer fluid flow; the heat transfer fluid circuit further includes a primary line, a bypass line, a three-way flow control valve, a temperature sensor, and a downstream line in flow communication between the three-way flow control valve and the heat transfer fluid pump; the primary line extends in flow communication between the first heat exchanger and the three-way flow control valve; the bypass line branches off from the primary line and is in upstream flow communication with the three-way flow control valve; the second heat exchanger is disposed within the primary line; the three-way flow control valve controls the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, combines the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, and directs the combined flow of heat transfer fluid to the heat transfer fluid pump; the temperature sensor is disposed in the heat transfer fluid circuit between the three-way flow control valve and the first heat exchanger; the three-way flow control valve controls the temperature of the heat transfer fluid between the three-way flow control valve and the first heat exchanger by adjusting the ratio of the flow rate of the warmed heat transfer fluid to the flow rate of the unwarmed heat transfer fluid within the combined heat transfer fluid stream; Station.

2. 1. A hydrogen refueling station comprising a liquid hydrogen source adapted and configured to store liquid hydrogen, a filling circuit, and a heat transfer fluid circuit, the filling circuit comprises an upstream end in downstream fluid communication with the liquid hydrogen source to permit the flow of liquid hydrogen from the liquid hydrogen source into the filling circuit, a downstream end adapted and configured to be removably connected to a hydrogen fuel vehicle tank for filling the hydrogen fuel vehicle tank, and a first heat exchanger disposed between the upstream end and the downstream end of the filling circuit; the heat transfer fluid circuit includes, in flow order, an upstream end in downstream flow communication with the first heat exchanger, a second heat exchanger, a heat transfer fluid pump, and a downstream end in upstream flow communication with the first heat exchanger, the heat transfer fluid pump adapted and configured to receive heat transfer fluid from the second heat exchanger and direct it to the first heat exchanger; the second heat exchanger is adapted and configured to warm the cooled heat transfer fluid received from the first heat exchanger; the first heat exchanger is adapted and configured to exchange heat between the heat transfer fluid flowing through the heat transfer fluid circuit and the liquid hydrogen in the filling circuit to cool the heat transfer fluid, and is further adapted and configured to vaporize the liquid hydrogen to provide pressurized gaseous hydrogen for filling the tank, the liquid hydrogen flow inside the first heat exchanger being surrounded by the heat transfer fluid flow; the station further comprises two or more buffer vessels, a leg branching off from the charging circuit downstream of the first heat exchanger adapted and configured to direct the pressurized gaseous hydrogen from the first heat exchanger to the two or more buffer vessels, a set of valves, and a pressure control valve; the set of valves is adapted and configured to allow the pressurized gaseous hydrogen to flow through the leg into one of the buffer vessels but not into the other of the buffer vessels, and to allow the pressurized gaseous hydrogen to flow from one of the buffer vessels back through the leg to the downstream end of the filling circuit; The pressure control valve is adapted and configured to control the pressure of the pressurized gaseous hydrogen flowing out of the downstream end of the filling circuit based on a pressure sensed by a pressure sensor disposed in the filling circuit between the leg and the downstream end of the filling circuit.

3. 1. A hydrogen refueling station comprising a liquid hydrogen source adapted and configured to store liquid hydrogen, a filling circuit, and a heat transfer fluid circuit, the filling circuit comprises an upstream end in downstream fluid communication with the liquid hydrogen source to permit the flow of liquid hydrogen from the liquid hydrogen source into the filling circuit, a downstream end adapted and configured to be removably connected to a hydrogen fuel vehicle tank for filling the hydrogen fuel vehicle tank, and a first heat exchanger disposed between the upstream end and the downstream end of the filling circuit; the heat transfer fluid circuit includes, in flow order, an upstream end in downstream flow communication with the first heat exchanger, a second heat exchanger, a heat transfer fluid pump, and a downstream end in upstream flow communication with the first heat exchanger, the heat transfer fluid pump adapted and configured to receive heat transfer fluid from the second heat exchanger and direct it to the first heat exchanger; the second heat exchanger is adapted and configured to warm the cooled heat transfer fluid received from the first heat exchanger; the first heat exchanger is adapted and configured to exchange heat between the heat transfer fluid flowing through the heat transfer fluid circuit and the liquid hydrogen in the filling circuit to cool the heat transfer fluid, and is further adapted and configured to vaporize the liquid hydrogen to provide pressurized gaseous hydrogen for filling the tank, the liquid hydrogen flow inside the first heat exchanger being surrounded by the heat transfer fluid flow; the charging circuit further comprises a primary line in fluid communication between the upstream end and the downstream end of the charging circuit, a bypass line branching from the primary line and rejoining the primary line downstream of the first heat exchanger, a flow control valve disposed in the primary line, a flow control valve disposed in the bypass line, and a temperature sensor disposed in the charging circuit downstream of the point where the bypass line rejoins the primary line and upstream of the downstream end of the charging circuit; the first heat exchanger is disposed within the primary line; the flow control valve disposed in the primary line is adapted and configured to control the flow of vaporized hydrogen through the primary line; the flow control valve disposed in the bypass line is adapted and configured to control the flow of liquid hydrogen through the bypass line; The flow control valve controls the flow of the vaporized hydrogen and the flow of the liquid hydrogen, which in turn controls the temperature of the pressurized gaseous hydrogen for filling the tank based on the temperature sensed by the temperature sensor.

4. 4. The station of claim 1, further comprising a liquid hydrogen pump in downstream flow communication with the liquid hydrogen source and in upstream flow communication with the first heat exchanger, the liquid hydrogen pump adapted and configured to increase the pressure of the flow of liquid hydrogen from the liquid hydrogen source and to direct the pressurized flow of liquid hydrogen towards the first heat exchanger.

5. 4. The station according to claim 1, wherein the filling circuit further comprises a pressure control valve and a pressure sensor downstream of the first heat exchanger, the pressure control valve being adapted and configured to control the pressure of the pressurized gaseous hydrogen for filling the tank based on the pressure of the pressurized gaseous hydrogen measured by the pressure sensor.

6. 4. The station of claim 1, wherein the heat transfer fluid circuit further comprises a blower adapted and configured to blow outside air at the second heat exchanger so as to warm the heat transfer fluid with heat from the blown outside air.

7. 4. The station of claim 1, wherein the second heat exchanger is an electric heater adapted and configured to warm the heat transfer fluid.

8. 4. The station of claim 1, wherein the heat transfer fluid circuit further comprises a heat transfer reservoir in fluid communication between the second heat exchanger and the heat transfer fluid pump, the heat transfer reservoir adapted and configured to contain a volume of the heat transfer fluid.

9. 1. A hydrogen refueling station adapted and configured to store liquid hydrogen, comprising: a liquid hydrogen source; first and second fill circuits; a heat transfer fluid reservoir; and first and second heat transfer fluid circuits, the first filling circuit comprises an upstream end in downstream fluid communication with the liquid hydrogen source to permit a flow of liquid hydrogen from the liquid hydrogen source into the first filling circuit, a downstream end adapted and configured to be removably connected to a hydrogen fuel vehicle tank for filling the hydrogen fuel vehicle tank, and a first heat exchanger disposed between the upstream end and the downstream end of the first filling circuit; the second filling circuit comprises an upstream end in downstream fluid communication with the liquid hydrogen source to permit a flow of liquid hydrogen from the liquid hydrogen source into the second filling circuit, a downstream end adapted and configured to be removably connected to a hydrogen fuel vehicle tank for filling the hydrogen fuel vehicle tank, and a first heat exchanger disposed between the upstream end and the downstream end of the second filling circuit; the first heat transfer fluid circuit comprising, in flow order, an upstream end in downstream flow communication with the first heat exchanger of the first charge circuit, a second heat exchanger, a heat transfer fluid pump, and a downstream end in upstream flow communication with the first heat exchanger of the first charge circuit; the heat transfer fluid pump of the first heat transfer fluid circuit is adapted and configured to receive heat transfer fluid from the second heat exchanger of the first heat transfer fluid circuit and direct it to the first heat exchanger of the first charge circuit; the second heat transfer fluid circuit comprising, in flow order, an upstream end in downstream flow communication with the first heat exchanger of the second charge circuit, a second heat exchanger, a heat transfer fluid pump, and a downstream end in upstream fluid communication with the first heat exchanger of the second charge circuit; the heat transfer fluid pump of the second heat transfer fluid circuit is adapted and configured to receive heat transfer fluid from the second heat exchanger of the second heat transfer fluid circuit and direct it to the first heat exchanger of the second charge circuit; the second heat exchanger of the first heat transfer fluid circuit is adapted and configured to warm the cooled heat transfer fluid received from the first heat exchanger of the first heat transfer fluid circuit; the second heat exchanger of the second heat transfer fluid circuit is adapted and configured to warm the cooled heat transfer fluid received from the first heat exchanger of the second heat transfer fluid circuit; the heat transfer fluid reservoir is in fluid communication between the second heat exchanger of the first heat transfer fluid circuit and a heat transfer fluid pump, and is in fluid communication between the second heat exchanger of the second heat transfer fluid circuit and the heat transfer fluid pump; the first heat exchanger of the first filling circuit is adapted and configured to exchange heat between the heat transfer fluid flowing through the first heat transfer fluid circuit and liquid hydrogen in the first filling circuit to cool the heat transfer fluid, and is further adapted and configured to vaporize the liquid hydrogen to provide pressurized gaseous hydrogen for filling a tank of a hydrogen-fueled vehicle, the liquid hydrogen flow inside the first heat exchanger of the first filling circuit being surrounded by the heat transfer fluid flow; the first heat exchanger of the second filling circuit is adapted and configured to exchange heat between the heat transfer fluid flowing through the second heat transfer fluid circuit and the liquid hydrogen in the second filling circuit to cool the heat transfer fluid, and is further adapted and configured to vaporize the liquid hydrogen to provide the pressurized gaseous hydrogen for filling a tank of a hydrogen-fueled vehicle, the flow of liquid hydrogen inside the first heat exchanger of the second filling circuit being surrounded by the flow of the heat transfer fluid.

10. a first liquid hydrogen pump in downstream flow communication with the liquid hydrogen source and in upstream flow communication with the first heat exchanger of the first filling circuit, the first liquid hydrogen pump adapted and configured to increase the pressure of the liquid hydrogen flow from the liquid hydrogen source and to direct the pressurized liquid hydrogen flow toward the first heat exchanger of the first filling circuit; and 10. The station of claim 9, further comprising a second liquid hydrogen pump in downstream flow communication with the liquid hydrogen source and in upstream flow communication with the first heat exchanger of the second filling circuit, the second liquid hydrogen pump adapted and configured to increase the pressure of the flow of liquid hydrogen from the liquid hydrogen source and to direct the pressurized flow of liquid hydrogen toward the first heat exchanger of the second filling circuit.

11. 10. The station of claim 9, wherein each of the filling circuits further comprises a pressure control valve and a pressure sensor downstream of the associated first heat exchanger, the pressure control valve adapted and configured to control the pressure of the pressurized gaseous hydrogen for filling a tank of a hydrogen-fueled vehicle based on the pressure of the pressurized gaseous hydrogen measured by the pressure sensor.

12. each of the heat transfer fluid circuits further comprising a primary line, a bypass line, a three-way flow control valve, a temperature sensor, and a downstream line in flow communication between the three-way flow control valve and the heat transfer fluid pump; each primary line extending in flow communication between an associated first heat exchanger and an associated three-way flow control valve; each bypass line branches off from an associated primary line and is in upstream flow communication with an associated said three-way flow control valve; each second heat exchanger is disposed within an associated primary line; each three-way flow control valve controls the flow of warmed heat transfer fluid from an associated primary line and the flow of unwarmed heat transfer fluid from an associated bypass line, combines the flow of warmed heat transfer fluid from an associated primary line and the flow of unwarmed heat transfer fluid from an associated bypass line, and directs the combined flow of heat transfer fluid to an associated heat transfer fluid pump; each temperature sensor is disposed in an associated heat transfer fluid circuit between an associated three-way flow control valve and an associated first heat exchanger; 10. The station of claim 9, wherein each three-way control valve controls the temperature of the heat transfer fluid between the respective three-way control valve and the associated first heat exchanger by adjusting the ratio of the flow rate of the warmed heat transfer fluid to the flow rate of the unwarmed heat transfer fluid within the combined heat transfer fluid stream.

13. 10. The station of claim 9, wherein each heat transfer fluid circuit further comprises a blower adapted and configured to blow ambient air across the associated second heat exchanger to warm the heat transfer fluid with heat from the blown ambient air.

14. 10. The station of claim 9, wherein each second heat exchanger is an electric heater adapted and configured to warm the heat transfer fluid.

15. Each fill circuit further comprises: a primary line in fluid communication between its upstream end and its downstream end; a bypass line branching off from the associated primary line and rejoining the associated primary line downstream of the associated first heat exchanger; a flow control valve disposed within the associated primary line; a flow control valve disposed in the associated bypass line; and a temperature sensor located downstream of the point where an associated bypass line rejoins an associated primary line, the temperature sensor being located upstream of the associated downstream end of the temperature sensor; the associated first heat exchanger is disposed within the associated primary line; the flow control valve disposed within the associated primary line is adapted and configured to control the flow of vaporized hydrogen through the associated primary line; the flow control valve disposed in the associated bypass line is adapted and configured to control the flow of the liquid hydrogen through the associated bypass line; 10. The station of claim 9, wherein the flow control valve controls the flow of the vaporized hydrogen and the flow of the liquid hydrogen, which in turn controls the temperature of the pressurized gaseous hydrogen for filling a tank of a hydrogen-fueled vehicle based on the temperature sensed by the temperature sensor.

16. 1. A method of filling a tank of a fuel cell vehicle with pressurized hydrogen, said method comprising: supplying liquid hydrogen from a liquid hydrogen source to a filling circuit removably connected at its downstream end to the tank, said filling circuit having a first heat exchanger disposed therein, said first heat exchanger having a liquid hydrogen inlet, a gaseous hydrogen outlet, a heat transfer fluid inlet, and a heat transfer fluid outlet; pumping the heat transfer fluid with a heat transfer fluid pump through a heat transfer fluid circuit looped with the first heat exchanger, the heat transfer fluid circuit including, in flow order from the heat transfer fluid outlet to the heat transfer fluid inlet, a second heat exchanger and the heat transfer fluid pump; exchanging heat between the heat transfer fluid flowing through the heat transfer fluid circuit and the liquid hydrogen supplied from the liquid hydrogen source to the charging circuit by the first heat exchanger, thereby vaporizing the supplied liquid hydrogen and cooling the heat transfer fluid, wherein the supplied liquid hydrogen inside the first heat exchanger is surrounded by the heat transfer fluid; heating the cooled heat transfer fluid received from the first heat exchanger with the second heat exchanger; and filling a tank of a hydrogen fuel vehicle with pressurized gaseous hydrogen from the downstream end of the filling circuit; the heat transfer fluid circuit further comprising a primary line, a bypass line, a three-way flow control valve, a temperature sensor, and a downstream line in flow communication between the three-way flow control valve and the heat transfer fluid pump; the primary line extends in flow communication between the first heat exchanger and the three-way flow control valve; the bypass line branches off from the primary line and is in upstream flow communication with the three-way flow control valve; the second heat exchanger is disposed within the primary line; the three-way flow control valve controls the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, combines the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, and directs the combined flow of heat transfer fluid to the heat transfer fluid pump; the temperature sensor is disposed in the heat transfer fluid circuit between the three-way flow control valve and the first heat exchanger; the three-way flow control valve controls the temperature of the heat transfer fluid between the three-way flow control valve and the first heat exchanger by adjusting the ratio of the flow rate of the warmed heat transfer fluid to the flow rate of the unwarmed heat transfer fluid within the combined heat transfer fluid stream.

17. 1. A method of filling a tank of a fuel cell vehicle with pressurized hydrogen, said method comprising: supplying liquid hydrogen from a liquid hydrogen source to a filling circuit removably connected at its downstream end to the tank, said filling circuit having a first heat exchanger disposed therein, said first heat exchanger having a liquid hydrogen inlet, a gaseous hydrogen outlet, a heat transfer fluid inlet, and a heat transfer fluid outlet; pumping the heat transfer fluid with a heat transfer fluid pump through a heat transfer fluid circuit looped with the first heat exchanger, the heat transfer fluid circuit including, in flow order from the heat transfer fluid outlet to the heat transfer fluid inlet, a second heat exchanger and the heat transfer fluid pump; exchanging heat between the heat transfer fluid flowing through the heat transfer fluid circuit and the liquid hydrogen supplied from the liquid hydrogen source to the charging circuit by the first heat exchanger, thereby vaporizing the supplied liquid hydrogen and cooling the heat transfer fluid, wherein the supplied liquid hydrogen inside the first heat exchanger is surrounded by the heat transfer fluid; heating the cooled heat transfer fluid received from the first heat exchanger with the second heat exchanger; and filling a tank of a hydrogen fuel vehicle with pressurized gaseous hydrogen from the downstream end of the filling circuit; The method further comprises providing two or more buffer vessels, a leg branching off from the charging circuit downstream of the first heat exchanger adapted and configured to direct the pressurized gaseous hydrogen from the first heat exchanger to two or more of the buffer vessels, a set of valves, and a pressure control valve; the set of valves is adapted and configured to allow the pressurized gaseous hydrogen to flow through the leg into one of the buffer vessels but not into the other of the buffer vessels, and to allow the pressurized gaseous hydrogen to flow from one of the buffer vessels back through the leg to the downstream end of the filling circuit; the pressure control valve is adapted and configured to control the pressure of the pressurized gaseous hydrogen flowing out of the downstream end of the filling circuit based on a pressure sensed by a pressure sensor disposed in the filling circuit between the leg and the downstream end of the filling circuit.

18. 1. A method of filling a tank of a fuel cell vehicle with pressurized hydrogen, said method comprising: supplying liquid hydrogen from a liquid hydrogen source to a filling circuit removably connected at its downstream end to the tank, said filling circuit having a first heat exchanger disposed therein, said first heat exchanger having a liquid hydrogen inlet, a gaseous hydrogen outlet, a heat transfer fluid inlet, and a heat transfer fluid outlet; pumping the heat transfer fluid with a heat transfer fluid pump through a heat transfer fluid circuit looped with the first heat exchanger, the heat transfer fluid circuit including, in flow order from the heat transfer fluid outlet to the heat transfer fluid inlet, a second heat exchanger and the heat transfer fluid pump; exchanging heat between the heat transfer fluid flowing through the heat transfer fluid circuit and the liquid hydrogen supplied to the filling circuit from the liquid hydrogen source in the first heat exchanger, thereby vaporizing the supplied liquid hydrogen and cooling the heat transfer fluid, wherein the supplied liquid hydrogen inside the first heat exchanger is surrounded by the heat transfer fluid; heating the cooled heat transfer fluid received from the first heat exchanger with the second heat exchanger; and filling a tank of a hydrogen fuel vehicle with pressurized gaseous hydrogen from the downstream end of the filling circuit; the charging circuit further comprises a primary line in fluid communication between the upstream end and the downstream end of the charging circuit, a bypass line branching from the primary line and rejoining the primary line downstream of the first heat exchanger, a flow control valve disposed in the primary line, a flow control valve disposed in the bypass line, and a temperature sensor disposed in the charging circuit downstream of the point where the bypass line rejoins the primary line and upstream of the downstream end of the charging circuit; the first heat exchanger is disposed within the primary line; the flow control valve disposed in the primary line is adapted and configured to control the flow of vaporized hydrogen through the primary line; the flow control valve disposed in the bypass line is adapted and configured to control the flow of liquid hydrogen through the bypass line; The flow control valve controls the flow of the vaporized hydrogen and the liquid hydrogen, which in turn controls the temperature of the pressurized gaseous hydrogen for filling the tank based on the temperature sensed by the temperature sensor.

19. 19. The method of any one of claims 16 to 18, further comprising pumping the liquid hydrogen from the liquid hydrogen source into the filling circuit with a liquid hydrogen pump.

20. measuring the pressure of the pressurized gaseous hydrogen in the charging circuit downstream of the first heat exchanger with a pressure sensor; and 19. The method according to any one of claims 16 to 18, further comprising the step of controlling the pressure of the pressurized gaseous hydrogen by a pressure control valve based on the pressure of the pressurized gaseous hydrogen measured by the pressure sensor.

21. 19. The method of any one of claims 16 to 18, wherein the heat transfer fluid circuit further comprises a blower adapted and configured to blow outside air at the second heat exchanger to warm the heat transfer fluid with heat from the blown outside air.

22. 19. The method of any one of claims 16 to 18, wherein the second heat exchanger is an electric heater adapted and configured to warm the heat transfer fluid.

23. 19. The method of any one of claims 16 to 18, wherein the heat transfer fluid circuit further comprises a heat transfer reservoir in fluid communication between the second heat exchanger and the heat transfer fluid pump, the heat transfer reservoir adapted and configured to contain a volume of the heat transfer fluid.

24. 1. A method of filling a tank of a fuel cell vehicle with pressurized hydrogen, said method comprising: supplying liquid hydrogen from a liquid hydrogen source to a filling circuit having a downstream end removably connected to a tank of a hydrogen fuel vehicle, said filling circuit having a first heat exchanger disposed therein, said first heat exchanger having a liquid hydrogen inlet, a gaseous hydrogen outlet, a heat transfer fluid inlet, and a heat transfer fluid outlet; pumping the heat transfer fluid with a heat transfer fluid pump through a heat transfer fluid circuit looped with the first heat exchanger, the heat transfer fluid circuit including, in flow order from the heat transfer fluid outlet to the heat transfer fluid inlet, a second heat exchanger and the heat transfer fluid pump; exchanging heat between the heat transfer fluid flowing through the heat transfer fluid circuit and the liquid hydrogen supplied from the liquid hydrogen source to the filling circuit by the first heat exchanger, thereby vaporizing the supplied liquid hydrogen and cooling the heat transfer fluid, wherein the supplied liquid hydrogen inside the first heat exchanger is surrounded by the heat transfer fluid; heating the cooled heat transfer fluid received from the first heat exchanger with the second heat exchanger; directing the vaporized liquid hydrogen into one or more buffer vessels; and filling a tank of a hydrogen fuelled vehicle with pressurised gaseous hydrogen from one or more of said buffer vessels; the heat transfer fluid circuit further comprising a primary line, a bypass line, a three-way flow control valve, a temperature sensor, and a downstream line in flow communication between the three-way flow control valve and the heat transfer fluid pump; the primary line extends in flow communication between the first heat exchanger and the three-way flow control valve; the bypass line branches off from the primary line and is in upstream flow communication with the three-way flow control valve; the second heat exchanger is disposed within the primary line; the three-way flow control valve controls the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, combines the flow of heated heat transfer fluid from the primary line and the flow of unheated heat transfer fluid from the bypass line, and directs the combined flow of heat transfer fluid to the heat transfer fluid pump; the temperature sensor is disposed in the heat transfer fluid circuit between the three-way flow control valve and the first heat exchanger; and the three-way flow control valve controls the temperature of the heat transfer fluid between the three-way flow control valve and the first heat exchanger by adjusting the ratio of the flow rate of the warmed heat transfer fluid to the flow rate of the unwarmed heat transfer fluid within the combined heat transfer fluid stream.

25. 1. A method of filling a tank of a fuel cell vehicle with pressurized hydrogen, said method comprising: supplying liquid hydrogen from a liquid hydrogen source to a filling circuit having a downstream end removably connected to a tank of a hydrogen fuel vehicle, said filling circuit having a first heat exchanger disposed therein, said first heat exchanger having a liquid hydrogen inlet, a gaseous hydrogen outlet, a heat transfer fluid inlet, and a heat transfer fluid outlet; pumping the heat transfer fluid with a heat transfer fluid pump through a heat transfer fluid circuit looped with the first heat exchanger, the heat transfer fluid circuit including, in flow order from the heat transfer fluid outlet to the heat transfer fluid inlet, a second heat exchanger and the heat transfer fluid pump; exchanging heat between the heat transfer fluid flowing through the heat transfer fluid circuit and the liquid hydrogen supplied from the liquid hydrogen source to the filling circuit by the first heat exchanger, thereby vaporizing the supplied liquid hydrogen and cooling the heat transfer fluid, wherein the supplied liquid hydrogen inside the first heat exchanger is surrounded by the heat transfer fluid; heating the cooled heat transfer fluid received from the first heat exchanger with the second heat exchanger; directing the vaporized liquid hydrogen into one or more buffer vessels; and filling a tank of a hydrogen fuelled vehicle with pressurised gaseous hydrogen from one or more of said buffer vessels; the one or more buffer encasements comprise two or more buffer encasements; a leg branching off from the charging circuit downstream of the first heat exchanger adapted and configured to direct the pressurized gaseous hydrogen from the first heat exchanger to one or more of the buffer vessels; a set of valves adapted and configured to allow the pressurized gaseous hydrogen to flow through the leg into one of the two or more buffer vessels but not into other of the two or more buffer vessels, and to allow the pressurized gaseous hydrogen to flow from one of the two or more buffer vessels back through the leg to the downstream end of the filling circuit; The method further comprises the step of controlling the pressure of the pressurized gaseous hydrogen flowing out of the downstream end of the filling circuit by using a pressure control valve based on the pressure sensed by a pressure sensor disposed in the filling circuit between the leg and the downstream end of the filling circuit.

26. 1. A method of filling a tank of a fuel cell vehicle with pressurized hydrogen, said method comprising: supplying liquid hydrogen from a liquid hydrogen source to a filling circuit having a downstream end removably connected to a tank of a hydrogen fuel vehicle, said filling circuit having a first heat exchanger disposed therein, said first heat exchanger having a liquid hydrogen inlet, a gaseous hydrogen outlet, a heat transfer fluid inlet, and a heat transfer fluid outlet; pumping the heat transfer fluid with a heat transfer fluid pump through a heat transfer fluid circuit looped with the first heat exchanger, the heat transfer fluid circuit including, in flow order from the heat transfer fluid outlet to the heat transfer fluid inlet, a second heat exchanger and the heat transfer fluid pump; exchanging heat between the heat transfer fluid flowing through the heat transfer fluid circuit and the liquid hydrogen supplied from the liquid hydrogen source to the filling circuit by the first heat exchanger, thereby vaporizing the supplied liquid hydrogen and cooling the heat transfer fluid, wherein the supplied liquid hydrogen inside the first heat exchanger is surrounded by the heat transfer fluid; heating the cooled heat transfer fluid received from the first heat exchanger with the second heat exchanger; directing the vaporized liquid hydrogen into one or more buffer vessels; and filling a tank of a hydrogen fuelled vehicle with pressurised gaseous hydrogen from one or more of said buffer vessels; the charging circuit further comprises a primary line in fluid communication between the upstream end and the downstream end of the charging circuit, a bypass line branching from the primary line and rejoining the primary line downstream of the first heat exchanger, a flow control valve disposed in the primary line, a flow control valve disposed in the bypass line, and a temperature sensor disposed in the charging circuit downstream of the point where the bypass line rejoins the primary line and upstream of the downstream end of the charging circuit; the first heat exchanger is disposed within the primary line; the flow control valve disposed in the primary line is adapted and configured to control the flow of vaporized hydrogen through the primary line; the flow control valve disposed in the bypass line is adapted and configured to control the flow of liquid hydrogen through the bypass line; The flow control valve controls the flow of the vaporized hydrogen and liquid hydrogen, which in turn controls the temperature of the pressurized gaseous hydrogen for filling the tank based on the temperature sensed by the temperature sensor.

27. 27. The method of any one of claims 24 to 26, further comprising pumping the liquid hydrogen from the liquid hydrogen source into the filling circuit with a liquid hydrogen pump.

28. measuring the pressure of the pressurized gaseous hydrogen in the charging circuit downstream of the first heat exchanger with a pressure sensor; and 27. The method according to any one of claims 24 to 26, further comprising the step of controlling the pressure of the pressurized gaseous hydrogen by a pressure control valve based on the pressure of the pressurized gaseous hydrogen measured by the pressure sensor.

29. 27. The method of any one of claims 24 to 26, wherein the heat transfer fluid circuit further comprises a blower adapted and configured to blow outside air at the second heat exchanger to warm the heat transfer fluid with heat from the blown outside air.

30. 27. The method of any one of claims 24 to 26, wherein the second heat exchanger is an electric heater adapted and configured to warm the heat transfer fluid.

31. 27. The method of any one of claims 24 to 26, wherein the heat transfer fluid circuit further comprises a heat transfer reservoir in fluid communication between the second heat exchanger and the heat transfer fluid pump, the heat transfer reservoir adapted and configured to contain a volume of the heat transfer fluid.

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