A fuel cell system with low temperature cold start function

Abstract

The application provides a fuel cell system with a low-temperature cold start function, comprising a temperature sensor, a fuel cell controller connected with an output end of the temperature sensor, and a power battery and a bidirectional DC-DC circuit module connected with an output end of the fuel cell controller; an output end of the bidirectional DC-DC circuit module is connected with a boost DC-DC circuit module, an output end of the boost DC-DC circuit module is connected with a fuel cell accessory system, and the fuel cell accessory system is connected with a stack. When the system is shut down in winter at low temperature, the shut-down purging time can be shortened, the service life of the system is improved, and customer satisfaction is improved.

Description

Technical Field

[0001] This invention relates primarily to the technical field of fuel cells, and more specifically to a fuel cell system with a low-temperature cold start function. Background Technology

[0002] A fuel cell is a chemical device that directly converts the chemical energy of fuel into electrical energy; it is also known as an electrochemical generator.

[0003] According to patent application CN201510741934.5, a low-temperature cold-start fuel cell system and its application method are disclosed. The fuel cell system includes a fuel cell system, a low-temperature cold-start heating device, a fuel cell control system, and a power-consuming terminal. The fuel cell system is connected to the low-temperature cold-start heating device, the fuel cell control system, and the power-consuming terminal. The fuel cell control system includes a control board and a control power supply. This invention not only accelerates the cold start of the fuel cell at low temperatures but also ensures the safe use of the fuel cell stack, preventing damage to the membrane electrode assembly (MEA), a core component of the stack. Furthermore, this method facilitates operation and control.

[0004] The aforementioned fuel cell system not only accelerates the cold start of the fuel cell at low temperatures but also ensures the safe use of the stack. However, traditional fuel cell systems suffer from problems such as failure to start up in low temperatures during winter, long purging times, and inability to power the vehicle after it stops, which affects the performance. Summary of the Invention

[0005] The present invention mainly provides a fuel cell system with low-temperature cold start function to solve the technical problems mentioned in the background art.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0007] A fuel cell system with low-temperature cold start function includes a temperature sensor, a fuel cell controller connected to the output terminal of the temperature sensor, and a power battery and a bidirectional DC-DC circuit module connected to the output terminal of the fuel cell controller.

[0008] The output terminal of the bidirectional DC-DC circuit module is connected to a boost DC-DC circuit module, and the output terminal of the boost DC-DC circuit module is connected to a fuel cell accessory system, which is connected to the fuel cell stack.

[0009] The boost DC-DC circuit module includes an air compressor controller (ACP), a high-voltage power distribution unit (PCU), and a buck DC-DC circuit connected to the output terminal of the bidirectional DC-DC circuit module. The output terminals of the high-voltage power distribution unit (PCU) and the buck DC-DC circuit are connected to the fuel cell accessory system.

[0010] One side of the fuel cell stack is provided with an oxygen pipeline and a steam pipeline. The output end of the steam pipeline is connected to a steam-water separator. The output end of the steam-water separator is connected to a compensation mechanism. The output end of the compensation mechanism is connected to a heat exchange jacket. The heat exchange jacket is located outside the fuel cell stack. In this invention, the steam portion is diverted through a three-way pipe, and a portion of it enters the compensation tank under the action of a pump between the steam-water separator and the compensation tank.

[0011] The heat exchange jacket is internally provided with a first serpentine infusion tube connected to the output end of the compensation mechanism, and a second serpentine infusion tube connected to the output end of the first serpentine infusion tube. The first serpentine infusion tube is located at the top of the fuel cell stack, and the second serpentine infusion tube is located on the lower surface of the fuel cell stack. In this invention, since the first serpentine infusion tube and the second serpentine infusion tube are located at the top and bottom ends of the fuel cell stack respectively, the fuel cell stack is fully preheated and kept warm.

[0012] The heat exchange jacket is provided with a plurality of heat exchange fins that are equidistantly arranged and installed on the outer surface of the fuel cell stack. The plurality of heat exchange fins are arranged in an alternating manner with the first serpentine infusion tube. In this invention, the fuel cell stack exchanges heat rapidly with the air inside the heat exchange jacket through the heat exchange fins.

[0013] The compensation mechanism includes a compensation tank connected to the output end of the gas-water separator. The liquid inlet of the compensation tank is connected to the liquid inlet of the first serpentine inlet tube via a pump body. The gas outlet of the compensation tank is connected to a gas inlet tube. The gas outlet of the gas inlet tube is connected to a three-way pipe. The gas outlet of the three-way pipe is connected to a gas outlet tube.

[0014] The compensation mechanism further includes a rotating heating roller disposed inside the compensation tank and rotatably connected to the compensation tank, and two temperature guide plates installed on the outer surface of the rotating heating roller. In this invention, the gas and liquid inside the compensation tank are heated by the rotating heating roller, and the heating area is expanded by the temperature guide plates. The compensation mechanism also includes a semiconductor cooler installed on one side surface of the temperature guide plates. In this invention, the temperature is reduced by the semiconductor cooler, and the cooling area is expanded by the temperature guide plates.

[0015] The compensation mechanism also includes a lifting plate sleeved on the outside of the rotating heating roller and slidably connected to the outer surface of the rotating heating roller. The lifting plate housing is provided with a vent hole and an air-blocking rubber cover installed on the upper surface of the lifting plate. In this invention, hot air flows into the three-way pipe through the air supply pipe, and after being diverted by the three-way pipe, it enters two air outlet pipes. Through multiple air outlets equidistantly arranged on the air outlet pipes, the hot air is evenly introduced into the space separated between the first serpentine infusion pipe and the heat exchange jacket.

[0016] A first chamfered cylinder is provided on the housing of the lifting plate. The first chamfered cylinder is sleeved outside the rotating heating roller and is slidably connected to the outer surface of the rotating heating roller. A second chamfered cylinder is slidably connected to the bottom end of the first chamfered cylinder and is installed on the outer surface of the rotating heating roller.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] Firstly, this invention can shorten the shutdown purging time during low-temperature shutdown in winter, thereby increasing system lifespan and improving customer satisfaction.

[0019] Secondly, this invention does not require the vehicle to provide power; the fuel cell system can provide its own power and complete the shutdown purging process, and the fuel cell system successfully achieves low-temperature cold start.

[0020] Third, the shutdown purging function shortens the low-temperature cold start time and improves the system's power demand response.

[0021] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the present invention;

[0023] Figure 2 This is a schematic diagram of the fuel cell stack of the present invention. Figure 1 ;

[0024] Figure 3 This is a schematic diagram of the fuel cell stack of the present invention. Figure 2 ;

[0025] Figure 4 This is an exploded view of the fuel cell stack of the present invention;

[0026] Figure 5 for Figure 4 Enlarged view of the structure of area A in the middle;

[0027] Figure 6 This is a schematic diagram of the fuel cell stack of the present invention. Figure 3 ;

[0028] Figure 7This is a bottom view of the fuel cell stack of the present invention;

[0029] Figure 8 This is a schematic diagram of the compensation mechanism of the present invention;

[0030] Figure 9 This is an exploded view of the compensation mechanism of the present invention.

[0031] In the diagram: 10. Temperature sensor; 20. Fuel cell controller; 30. Power battery; 40. Bidirectional DC-DC circuit module; 50. Boost DC-DC circuit module; 60. Fuel cell accessory system; 70. Stack; 71. Oxygen pipeline; 72. Water vapor pipeline; 73. Gas-water separator; 74. Compensation mechanism; 741. Compensation tank; 742. Rotary heating roller; 743. Temperature guide plate; 744. Semiconductor cooler; 745. Lifting plate; 7451. First chamfered cylinder; 7452. Second chamfered cylinder; 7453. Vent; 7454. Air baffle cap; 746. Gas outlet pipe; 747. T-connector; 748. Gas delivery pipe; 75. Heat exchange jacket; 751. First serpentine infusion pipe; 752. Second serpentine infusion pipe; 753. Heat exchange fins. Detailed Implementation

[0032] To facilitate understanding of the present invention, a more comprehensive description of the present invention will be given below with reference to the accompanying drawings, which illustrate several embodiments of the present invention. However, the present invention can be implemented in different forms and is not limited to the embodiments described in the text. Rather, these embodiments are provided to make the disclosure of the present invention more thorough and complete.

[0033] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly associated with those skilled in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0035] For an example, please refer to the appendix. Figure 1-9A fuel cell system with low-temperature cold start function includes a temperature sensor 10, a fuel cell controller 20 connected to the output terminal of the temperature sensor 10, and a power battery 30 and a bidirectional DC-DC circuit module 40 connected to the output terminal of the fuel cell controller 20.

[0036] The output terminal of the bidirectional DC-DC circuit module 40 is connected to the boost DC-DC circuit module 50, the output terminal of the boost DC-DC circuit module 50 is connected to the fuel cell accessory system 60, and the fuel cell accessory system 60 is connected to the fuel cell stack 70.

[0037] It should be noted that, in this embodiment, the boost DC-DC circuit module 50 includes an air compressor controller ACP51, a high-voltage power distribution unit PCU52, and a buck DCL circuit 53 connected to the output terminal of the bidirectional DC-DC circuit module 40. The output terminals of the high-voltage power distribution unit PCU52 and the buck DCL circuit 53 are connected to the fuel cell accessory system 60.

[0038] For details, please refer to the appendix. Figure 2 , 3 6 and 7, one side of the fuel cell stack 70 is provided with an oxygen pipe 71 and a steam pipe 72. The output end of the steam pipe 72 is connected to a steam-water separator 73. The output end of the steam-water separator 73 is connected to a compensation mechanism 74. The output end of the compensation mechanism 74 is connected to a heat exchange jacket 75. The heat exchange jacket 75 is located outside the fuel cell stack 70.

[0039] The heat exchange jacket 75 is provided with a first serpentine infusion tube 751 connected to the output end of the compensation mechanism 74, and a second serpentine infusion tube 752 connected to the output end of the first serpentine infusion tube 751. The first serpentine infusion tube 751 is located at the top of the fuel cell stack 70, and the second serpentine infusion tube 752 is located on the lower surface of the fuel cell stack 70.

[0040] The heat exchange jacket 75 has a plurality of heat exchange fins 753 arranged at equal intervals and installed on the outer surface of the fuel cell stack 70. The plurality of heat exchange fins 753 are arranged alternately with the first serpentine infusion tube 751.

[0041] The compensation mechanism 74 includes a compensation tank 741 connected to the output end of the gas-water separator 73. The liquid inlet of the compensation tank 741 is connected to the liquid inlet of the first serpentine inlet tube 751 via a pump body. The gas outlet of the compensation tank 741 is connected to a gas inlet tube 748. The gas outlet of the gas inlet tube 748 is connected to a three-way tube 747. The gas outlet of the three-way tube 747 is connected to a gas outlet tube 746.

[0042] It should be noted that, in this embodiment, the water vapor discharged from the fuel cell stack 70 is separated by the steam-water separator 73, and part of the water vapor is diverted through the three-way pipe 747. Part of it enters the compensation tank 741 under the action of the pump body between the steam-water separator 73 and the compensation tank 741, thereby supplying gas to the compensation tank 741. A one-way valve is installed on the pipeline between the pump body and the steam-water separator 73 and the compensation tank 741 to prevent the gas inside the compensation tank 741 from flowing back.

[0043] Furthermore, the hot water heated by the compensation tank 741 enters the second serpentine infusion tube 752 through the first serpentine infusion tube 751. Since the first serpentine infusion tube 751 and the second serpentine infusion tube 752 are located at the upper and lower ends of the fuel cell stack 70 respectively, the fuel cell stack 70 is fully preheated and kept warm.

[0044] Furthermore, the fuel cell stack 70 rapidly exchanges heat with the air inside the heat exchange jacket 75 through the heat exchange fins 753;

[0045] Furthermore, the liquid stored at the bottom of the compensation tank 741 is heated or cooled. After the pump between the compensation tank 741 and the inlet end of the first serpentine infusion tube 751 starts working, the liquid in the compensation tank 741 enters the first serpentine infusion tube 751 through the pump, thereby supplying liquid to the first serpentine infusion tube 751. The first serpentine infusion tube 751 is connected to an external heat source and a cold source to maintain a continuous supply of liquid inside the first serpentine infusion tube 751. The outlet end of the second serpentine infusion tube 752 is connected to the bottom inlet end of the compensation tank 741 for circulating heating.

[0046] For details, please refer to the appendix. Figure 8 and 9 The compensation mechanism 74 further includes a rotary heating roller 742 disposed inside the compensation tank 741 and rotatably connected to the compensation tank 741, and two temperature guiding plates 743 installed on the outer surface of the rotary heating roller 742.

[0047] The compensation mechanism 74 also includes a semiconductor cooler 744 installed on one side surface of the temperature-conducting plate 743;

[0048] The compensation mechanism 74 further includes a lifting plate 745 sleeved on the outside of the rotating heating roller 742 and slidably connected to the outer surface of the rotating heating roller 742. The lifting plate 745 has a vent hole 7453 on its housing and an air-blocking rubber cover 7454 installed on the upper surface of the lifting plate 745.

[0049] A first chamfered cylinder 7451 is provided on the housing of the lifting plate 745. The first chamfered cylinder 7451 is sleeved on the outside of the rotating heating roller 742 and is slidably connected to the outer surface of the rotating heating roller 742. A second chamfered cylinder 7452 is slidably connected to the bottom end of the first chamfered cylinder 7451 and is installed on the outer surface of the rotating heating roller 742.

[0050] It should be noted that in this embodiment, the gas and liquid inside the compensation tank 741 are heated by the rotating heating roller 742, and the heating area is expanded by the temperature guiding plate 743.

[0051] Furthermore, cooling is achieved through a semiconductor cooler 744, and the cooling area is expanded through a heat-conducting plate 743;

[0052] Furthermore, when the lifting plate 745 descends, the space at the bottom of the lifting plate 745 is continuously compressed, causing the heated air in the space to push open the air-blocking rubber cover 7454 and pass through the vent 7453, and be stored in the space at the top of the lifting plate 745. When the lifting plate 745 rises, the air in the space is compressed by the lifting plate 745, causing the air in the space to flow into the three-way pipe 747 through the air supply pipe 748. After being split by the three-way pipe 747, the air enters the two air outlet pipes 746. Through the multiple air outlets equidistantly arranged on the air outlet pipes 746, the hot air is evenly introduced into the space between the first serpentine infusion pipe 751 and the heat exchange jacket 75.

[0053] Furthermore, the rotating heating roller 742 is driven by a motor to rotate, so that the rotating heating roller 742 drives the second chamfering cylinder 7452 to rotate. The inclined surface of the second chamfering cylinder 7452 slides on the inclined surface of the first chamfering cylinder 7451, so that the first chamfering cylinder 7451 is continuously raised and lowered, thereby driving the lifting plate 745 to continuously rise and fall.

[0054] The specific operation method of this invention is as follows:

[0055] In low-temperature winter conditions, the fuel cell controller 20 is periodically woken up. The temperature sensor 10 detects the environment. If the temperature T is lower than the set threshold, and the PPG needs to be purged, the fuel cell controller 20 sends a wake-up signal IRQ to wake up the power battery 30 and the bidirectional DC-DC circuit module 40. After receiving the IRQ signal, the power battery 30 acts as a power source, and the bidirectional DC-DC circuit module 40 operates, outputting a constant voltage to supply high-voltage power to the step-down DCL circuit 53, the air compressor controller ACP 51, and the high-voltage power distribution unit PCU 52. The step-down DCL circuit 53 and the high-voltage power distribution unit PCU 52 provide high and low voltage power to the fuel cell accessory system 60, and the fuel cell starts running. After the fuel cell temperature reaches the set threshold and the purging is completed, the fuel cell controller 20, the power battery 30, and the bidirectional DC-DC circuit module 40 enter sleep mode.

[0056] The present invention has been described by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvement made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, shall be within the protection scope of the present invention.

Claims

1. A fuel cell system with low-temperature cold start function, characterized in that, It includes a temperature sensor (10), a fuel cell controller (20) connected to the output terminal of the temperature sensor (10), and a power battery (30) and a bidirectional DC-DC circuit module (40) connected to the output terminal of the fuel cell controller (20). The output of the bidirectional DC-DC circuit module (40) is connected to a boost DC-DC circuit module (50), the output of the boost DC-DC circuit module (50) is connected to a fuel cell accessory system (60), and the fuel cell accessory system (60) is connected to the fuel cell stack (70); an oxygen pipe (71) and a water vapor pipe (72) are provided on one side of the fuel cell stack (70), the output of the water vapor pipe (72) is connected to a steam-water separator (73), the output of the steam-water separator (73) is connected to a compensation mechanism (74), the output of the compensation mechanism (74) is connected to a heat exchange jacket (75), and the heat exchange jacket (75) is located outside the fuel cell stack (70); The heat exchange jacket (75) is provided with a first serpentine infusion tube (751) connected to the output end of the compensation mechanism (74), and a second serpentine infusion tube (752) connected to the output end of the first serpentine infusion tube (751). The first serpentine infusion tube (751) is located at the top of the fuel cell stack (70), and the second serpentine infusion tube (752) is located on the lower surface of the fuel cell stack (70). The compensation mechanism (74) includes a compensation tank (741) connected to the output end of the steam-water separator (73). The liquid inlet of the compensation tank (741) is connected to the liquid inlet of the first serpentine inlet pipe (751) via a pump body. The gas outlet of the compensation tank (741) is connected to a gas inlet pipe (748). The gas outlet of the gas inlet pipe (748) is connected to a three-way pipe (747). The gas outlet of the three-way pipe (747) is connected to a gas outlet pipe (746). The compensation mechanism (74) also includes a rotating heating roller (742) disposed inside the compensation tank (741) and rotatably connected to the compensation tank (741), and two temperature-conducting plates installed on the outer surface of the rotating heating roller (742). 743); The compensation mechanism (74) further includes a semiconductor cooler (744) installed on one side surface of the temperature guide plate (743); The compensation mechanism (74) further includes a lifting plate (745) sleeved on the outside of the rotating heating roller (742) and slidably connected to the outer surface of the rotating heating roller (742), the lifting plate (745) housing is provided with a vent hole (7453), and an air-blocking rubber cover (7454) installed on the upper surface of the lifting plate (745); The boost DC-DC circuit module (50) includes an air compressor controller ACP (51), a high-voltage power distribution unit PCU (52) and a step-down DCL circuit (53) connected to the output end of the bidirectional DC-DC circuit module (40), the output ends of the high-voltage power distribution unit PCU (52) and the step-down DCL circuit (53) are connected to the fuel cell accessory system (60); The heat exchange jacket (75) is provided with a plurality of heat exchange fins (753) arranged at equal intervals and installed on the outer surface of the fuel cell stack (70). The plurality of heat exchange fins (753) are arranged alternately with the first serpentine infusion tube (751). A first chamfered cylinder (7451) is provided on the shell of the lifting plate (745). The first chamfered cylinder (7451) is sleeved on the outside of the rotating heating roller (742) and is slidably connected to the outer surface of the rotating heating roller (742). A second chamfered cylinder (7452) is slidably connected to the bottom end of the first chamfered cylinder (7451). The second chamfered cylinder (7452) is installed on the outer surface of the rotating heating roller (742).

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