Fuel cell for EV charging

Abstract

The present application provides illustrative example embodiments of a method and system that use a fuel cell to generate electricity to charge an electrically powered vehicle and provide additional output for cooling a charging cable of the vehicle.

Description

Background Art

[0001] As electric vehicles become more popular, the demand for charging stations has also increased. In addition, fast charging stations are becoming popular to charge more in a shorter period of time. Fast charging generates more waste heat in the cables. One way to solve this problem is to use large cables that can accommodate the heat; however, these cables are bulky and difficult to move around. Another approach is to provide actively cooled charging cables; however, this requires additional cooling components and additional energy to provide active cooling. Summary of the invention

[0002] An illustrative example embodiment of a method includes using a fuel cell to generate electricity to charge a vehicle.

[0003] In an embodiment having one or more of the features of the method of the preceding paragraphs, the method includes using heat from a fuel cell reaction of the fuel cell to drive a cooling process to cool a charging cable of the vehicle.

[0004] In an embodiment having one or more features of the method of any of the preceding paragraphs, the fuel cell comprises a phosphoric acid fuel cell (PAFC), and the method comprises: generating waste heat from the PAFC; generating cold from the waste heat via a cooling process; and cooling a charging cable of the vehicle with the cold.

[0005] In an embodiment having one or more features of the method of any of the preceding paragraphs, the method includes: cooling a water byproduct of the fuel cell power plant with cold energy to provide cooling water; and cooling the charging cable with the cooling water.

[0006] In an embodiment having one or more features of the method of any of the preceding paragraphs, the step of generating cold from waste heat comprises using an absorption chiller.

[0007] In an embodiment having one or more features of the method of any of the preceding paragraphs, the charging cable is for use in a fast charging station.

[0008] In an embodiment having one or more features of the method of any of the preceding paragraphs, the fuel cell comprises a cell stack assembly in a fuel cell power plant.

[0009] An illustrative example embodiment of a system includes: a fuel cell; and an output connectable to an EV charger, wherein electricity generated by the fuel cell is delivered to the output.

[0010] In an embodiment having one or more features of the system of any of the preceding paragraphs, an EV charger may be connected to a vehicle to charge the vehicle.

[0011] In an embodiment having one or more features of the system of any of the preceding paragraphs, the system further comprises a charging cable connecting the EV charger to the vehicle, and wherein the fuel cell provides additional output to cool the charging cable.

[0012] In an embodiment having one or more features of the system of any of the preceding paragraphs, the fuel cell comprises a phosphoric acid fuel cell (PAFC), and wherein the PAFC generates waste heat for generating refrigeration for cooling the charging cable.

[0013] In an embodiment having one or more features of the system of any of the preceding paragraphs, the water byproduct of the fuel cell power plant is cooled with cold energy to provide cooling water, and wherein the cooling water cools the charging cable.

[0014] In an embodiment having one or more features of the system of any of the preceding paragraphs, the system further comprises an absorption chiller that generates cold from waste heat.

[0015] In an embodiment having one or more features of the system of any of the preceding paragraphs, the PAFC includes a cell stack of the PAFC.

[0016] In an embodiment having one or more features of the system of any of the preceding paragraphs, the charging cable is for use in a fast charging station.

[0017] In an embodiment having one or more features of the system of any of the preceding paragraphs, the fuel cell comprises a cell stack assembly in a fuel cell power plant.

[0018] The various features and advantages of at least one disclosed example embodiment will become apparent to those skilled in the art from the following detailed description.The drawings accompanying the detailed description can be briefly described as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 An exemplary electric vehicle at a charging station is schematically shown.

[0020] Figure 2 An example fuel cell power plant is schematically shown.

[0021] Figure 3 is a schematic diagram showing a method of charging an electric vehicle and / or cooling a charging component using a fuel cell.

[0022] Figure 4 An exemplary fuel cell is shown schematically.

[0023] Figure 5 An example absorption chiller is schematically shown. DETAILED DESCRIPTION

[0024] Embodiments of the present application are directed to a method and system for using a fuel cell to generate electricity to charge a vehicle and provide an additional output for cooling a charging cable of the vehicle.

[0025] Figure 1 An exemplary electric vehicle 20 is schematically shown being charged at a charging station 22. The electric vehicle 20 includes a charging port 24. At least one charging cable 26 connects a charging power source 28 of the charging station 22 to the charging port 24. The charging power source 28 is used to charge a high voltage battery pack (not shown) located within the electric vehicle 20 in a known manner. The operation of the charging station 22 and the charging of the electric vehicle 20 are accomplished using known techniques and existing structures.

[0026] As EV vehicles 20 become more popular, the demand for charging stations 22 will increase. These charging stations 22 will require additional power sources to meet the demand. The current grid infrastructure may not be able to support this demand in a cost-effective manner. In addition, fast charging stations are needed to provide more charging in a shorter period of time. Fast charging generates more waste heat in the cables due to IR losses. The present application uses fuel cell technology in a cost-effective manner to provide a power source that is different from the current power infrastructure for charging services. The present application also uses fuel cell technology to provide a cooling source for the charging stations.

[0027] Figure 2 Selected portions of an exemplary fuel cell power generation device 30 are schematically shown. A cell stack assembly (CSA) 32 includes a plurality of fuel cells that generate electricity based on an electrochemical reaction. Fuel cells can take a variety of forms. For example, some fuel cells can be phosphoric acid fuel cells (PAFCs), while other fuel cells can be polymer electrolyte membrane fuel cells (PEMs). With the benefit of this description, those skilled in the art will be able to select the appropriate type of fuel cell and CSA arrangement to meet their specific needs.

[0028] In one example, the fuel 34 is sent to a fuel cell processing and delivery system 36, which feeds into the CSA 32, as shown at 38. The CSA 32 generates direct current (DC) 40, which is transmitted to a power conversion system 42, such as an inverter, where the direct current (DC) from the CSA 32 is converted into alternating current (AC) 44, which is then provided to an external load of the fuel cell power plant 30. Air 46 is supplied to the CSA 32, and a thermal management and heat recovery system 48 is used to thermally manage the fuel cell supply 38, the air supply 46, and the CSA 32, as shown by arrows 50, 52, and 54, respectively. As shown at 56, the output from the thermal management and heat recovery system 48 includes waste heat and H2O (CO2),.

[0029] The controller 58 controls the operation of the power conversion system 42 to obtain the desired operation and output from the fuel cell power plant 30. The controller 58 also controls the thermal management and heat recovery system 48 and the AC power output 44. The fuel cell power plant 30 also includes additional auxiliary systems and instruments 60 required for the operation of the fuel cell power plant 30. It should be understood that this is only one example of a fuel cell power plant 30 and other configurations may also be used.

[0030] The present application uses one or more fuel cells 62 to generate electricity 64 to charge the electric vehicle 20, such as Figure 3 The fuel cell 62 also provides an additional output 66 for cooling the charging cable 26 of the electric vehicle 20 .

[0031] Figure 4 An example of a fuel cell 62 is shown. In this example, the fuel cell 62 includes a PAFC 68. The PAFC 68 generates electrical energy based on an electrochemical reaction involving hydrogen and oxygen. The PAFC uses liquid phosphoric acid as an electrolyte 70. An anode 72 and an anode catalyst layer 74 are located on one side of the electrolyte 70, while a cathode 76 and a cathode catalyst layer 78 are located on the opposite side of the electrolyte 70. A supply 80 of H2 is supplied to the anode gas diffusion layer 82 via an inlet 84, and unused H2 86 leaves via an outlet 88. The cathode 76 is supplied with O2 90 from ambient air, which is directed to the cathode gas diffusion layer 92 via an inlet 94.

[0032] Positively charged hydrogen ions 96 migrate from anode 72 through electrolyte 70 to cathode 76. Electrons 98 generated at anode 72 travel through external circuit 100, providing power, and return to cathode 76. H2 combines with O2 on the cathode side and exits via outlet 102 as H2O.

[0033] The electrical energy generated by the PAFC 68 includes electricity that can be used to charge the electric vehicle 20. The PAFC 68 also has an additional output to provide cooling functions. As described above, the fuel cell 62 generates waste heat 56 (see Figure 2 and Figure 3 In one example, the absorption chiller 104 uses the energy of the waste heat 56 to provide cooling 106. The absorption chiller 104 uses the waste heat collected from other processes or equipment to drive a thermodynamic process that causes water to be cooled and distributed for other heating and cooling needs.

[0034] Figure 5An example of an absorption refrigeration machine 104 is shown. In this example, the absorption refrigeration machine 104 has a condenser 120, a generator 122, an evaporator 124, an absorber 126 and a heat exchanger 128. Refrigerant or other suitable fluids, such as a mixture of water and lithium bromide, are stored in the absorber 126. The fluid is pumped through the heat exchanger 128 to reach the tank of the generator 122. The waste heat generated from the fuel cell power generation device 30 enters the generator 122, and then the water is separated under the heat. The water gradually becomes steam and rises to the top where the condenser 120 is located, and the remaining separated part is directed back to the absorber 126. Then, the steam in the condenser 120 at the top will pass through the cooling tower. The air pressure of the cooling tower pipe is lower than that of the condenser 120. Therefore, when the air pressure decreases, the steam becomes water again. The cold water then enters the evaporator 124 and waits to be mixed with the fluid from the absorber 126.

[0035] In short, the absorption chiller 104 cools water through a sudden change in pressure. When the water is heated in the generator 122, the air pressure is high. The water releases the heat and turns into steam. Then, pipes direct the steam to the evaporator 124, where the air pressure is low. The steam will then immediately cool and turn into cold water again. As the steam absorbs heat and turns into water, the outside temperature will drop. The water evaporates and takes away all the unwanted heat. Then, when the steam passes through the cooling tower, the steam cools in the low-pressure environment and turns into water again. Therefore, the absorption chiller 104 produces chilled water while consuming only a small amount of electricity.

[0036] It should be understood that Figure 5 The absorption chiller 104 is only one example, and any type of absorption chiller may be used to provide cooling capacity. A person skilled in the art having the benefit of this description will be able to select an appropriate type of absorption chiller to meet their specific needs.

[0037] In one example, waste heat from the fuel cell 62 is used to heat water. The resulting hot water is then fed to the absorption chiller 104 to produce chilled water, which can then be used to cool the EV cable 26, as shown at 110. The hot water from the fuel cell power plant will be at a lower temperature after interacting with the absorption chiller 104. This water can then be fed to the fuel cell power plant 30 and reheated in a continuous cycle.

[0038] Therefore, the present application uses the fuel cell to provide both the charging function and the cooling function. This is beneficial as a load that follows the power source while also providing a previously unused cooling source that would otherwise require the use of additional energy to satisfy the cooling source.

[0039] The foregoing description is exemplary rather than restrictive in nature. Changes and modifications to the disclosed examples may become apparent to those skilled in the art without necessarily departing from the essence of the present application. The scope of legal protection afforded to this application can only be determined by studying the attached claims.

Claims

1. A method comprising: A fuel cell is used to generate electricity to charge the vehicle.

2. The method according to claim 1, comprising: Heat from a fuel cell reaction of the fuel cell is used to drive a cooling process to cool a charging cable of the vehicle.

3. The method according to claim 2, wherein: The fuel cell comprises a phosphoric acid fuel cell (PAFC), and the method comprises: generating waste heat from the phosphoric acid fuel cell PAFC; generating cold from the waste heat through the cooling process; and The cold energy is used to cool a charging cable for the vehicle.

4. The method according to claim 3, comprising: Using the cold energy to cool the water byproduct of the fuel cell power generation device to provide cooling water; as well as The charging cable is cooled using the cooling water.

5. The method according to claim 3, wherein: The step of generating cold from the waste heat may include using an absorption chiller.

6. The method according to claim 2, wherein: The charging cable is for use in a fast charging station.

7. The method of claim 1, wherein the fuel cell comprises a cell stack assembly in a fuel cell power plant.

8. A system comprising: Fuel cells; as well as An output is connectable to an electric vehicle (EV) charger, wherein the fuel cell generates electricity that is delivered to the output.

9. The system according to claim 8, wherein: The electric vehicle (EV) charger is connectable to a vehicle to charge the vehicle.

10. The system of claim 9, comprising a charging cable connecting the EV charger to the vehicle, and wherein, The fuel cell provides additional output to cool the charging cable.

11. The system according to claim 10, wherein: The fuel cell comprises a phosphoric acid fuel cell PAFC, and wherein the phosphoric acid fuel cell PAFC generates waste heat for generating cold energy, and the cold energy is used to cool the charging cable.

12. The system according to claim 11, wherein: The water byproduct of the fuel cell power plant is cooled with cold energy to provide cooling water, and wherein the cooling water cools the charging cable.

13. The system of claim 11, comprising an absorption chiller that generates cold from waste heat.

14. The system according to claim 11, wherein: The phosphoric acid fuel cell PAFC includes a phosphoric acid fuel cell stack.

15. The system according to claim 10, wherein: The charging cable is for use in a fast charging station.

16. The system according to claim 8, wherein: The fuel cell comprises a cell stack assembly in a fuel cell power generation device.

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