A device for real-time nitrogen and water management of batteries

Abstract

The present invention provides a device for real-time nitrogen and water management of a battery, comprising a gas supply unit, a flow sensor, a temperature and humidity sensor, a heating module, a cooling module, a hydrogen concentration sensor, a data acquisition unit and a data processing unit. The gas supply unit can provide the gas required by the fuel cell, the flow sensor and the temperature and humidity sensor are respectively distributed at the anode and cathode inlets and outlets of the battery and are connected to the battery stack, the heating module is connected to the cathode outlet pipeline of the fuel cell, the cooling module is connected to the anode outlet pipeline of the battery, the flow sensor, the temperature and humidity sensor, the hydrogen concentration sensor are connected to the data acquisition unit, and the data processing unit is connected to the data acquisition unit. The beneficial effect of the present invention is that the water management of the anode and cathode of the fuel cell and the nitrogen management of the anode are accurately measured and monitored in real time without affecting the operation of the stack, thereby improving the stability and durability of the fuel cell.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a device for real-time nitrogen and water management of a battery. Background Art

[0002] Proton exchange membrane fuel cells (PEMFCs) are power generation devices that generate electricity through an electrochemical reaction between hydrogen and oxygen. They offer numerous advantages, including high energy conversion efficiency, environmental friendliness, and low noise. The performance and durability of PEMFCs are affected by many factors, among which water management has long been a crucial factor affecting their performance and lifespan. On the one hand, an insufficiently moistened PEM has low proton conductivity, which increases the overall impedance of the fuel cell and affects its output power. On the other hand, excessive water accumulation not only hinders the passage of reactant gases through the gas diffusion layer to the reaction interface but also causes a loss of effective catalyst surface area, exacerbating material degradation such as dissolution, corrosion, and contamination of polymers, leading to a decrease in PEMFC performance and lifespan. This phenomenon is commonly referred to as fuel cell "flooding." Currently, the assessment of water content within PEMFCs relies primarily on AC impedance measurement, which uses changes in the AC impedance spectrum to determine the water status within the fuel cell. However, due to the need to sample the steady-state output voltage at different AC current frequencies, AC impedance spectroscopy measurements take a long time, making online, real-time measurement difficult.

[0003] In addition to fuel cell water management, nitrogen management also impacts fuel cell performance and lifespan. During operation, pressurized air flows into the cathode, while pure hydrogen, depressurized from a hydrogen cylinder, flows into the anode. After the electrochemical reaction, the oxygen in the cathode air is consumed, and nitrogen accumulates at the cathode. Due to the diffusion effect caused by the concentration difference, nitrogen on the cathode side continuously diffuses toward the anode. The increasing nitrogen concentration on the anode side reduces the fuel cell's power generation and damages the catalyst, making nitrogen concentration management on the anode side of the proton exchange membrane fuel cell crucial.

[0004] Therefore, a device for real-time monitoring of water and nitrogen in a proton exchange membrane fuel cell is needed. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention discloses a device and method for real-time nitrogen and water management of batteries. The technical solution of the present invention is implemented as follows:

[0006] A device for real-time nitrogen and water management of a battery includes an anode pipeline, a cathode pipeline, an air supply unit, a flow sensor, a temperature and humidity sensor, a hydrogen concentration sensor, a data acquisition unit, and a data processing unit. The anode pipeline is connected to the anode chamber of the battery, the cathode pipeline is connected to the cathode chamber of the battery, the air supply unit is connected to the inlet of the anode pipeline and the inlet of the cathode pipeline, respectively, the inlet of the anode pipeline, the outlet of the anode pipeline, the inlet of the cathode pipeline, and the outlet of the cathode pipeline are all provided with a flow sensor and a temperature and humidity sensor, the outlet of the anode pipeline is further provided with a second cooling module, a third cooling module, and a second heating module, the outlet of the cathode pipeline is provided with a first cooling module and a first heating module, the hydrogen sensor is provided at the outlet of the anode pipeline, the flow sensor, the temperature and humidity sensor, and the hydrogen concentration sensor are connected to the data acquisition unit, and the data processing unit is connected to the data acquisition unit.

[0007] Preferably, the flow sensor includes a first flow sensor, a second flow sensor, a third flow sensor, a fourth flow sensor, a fifth flow sensor, a sixth flow sensor, a seventh flow sensor and an eighth flow sensor, the first flow sensor is arranged at the inlet of the cathode pipeline, the second flow sensor, the third flow sensor and the fourth flow sensor are arranged at the outlet of the cathode pipeline, the fifth flow sensor is arranged at the inlet of the anode pipeline, the sixth flow sensor, the seventh flow sensor and the eighth flow sensor are arranged at the outlet of the anode pipeline, and the temperature and humidity sensor includes a first temperature and humidity sensor, a second temperature and humidity sensor, a third temperature and humidity sensor, a fourth temperature and humidity sensor, a fifth temperature and humidity sensor and a sixth temperature and humidity sensor, the first temperature and humidity sensor is arranged at the inlet of the cathode pipeline, the second temperature and humidity sensor and the third temperature and humidity sensor are arranged at the outlet of the cathode pipeline, the fourth temperature and humidity sensor is arranged at the inlet of the anode pipeline, and the fifth temperature and humidity sensor and the sixth temperature and humidity sensor are arranged at the outlet of the anode pipeline.

[0008] Preferably, the gas supply unit comprises a cathode gas supply module and an anode gas supply module, the cathode gas supply module is connected to the inlet of the cathode pipeline, and the anode gas supply module is connected to the inlet of the anode pipeline.

[0009] Preferably, the cathode gas supply module provides a mixed gas of air and water vapor, and the anode gas supply module provides a mixed gas of hydrogen and water vapor.

[0010] Preferably, it also includes a first solenoid valve, a second solenoid valve, a third solenoid valve, a fourth solenoid valve, a fifth solenoid valve and a sixth solenoid valve, the first solenoid valve, the second solenoid valve, the third solenoid valve and the fourth solenoid valve are arranged at the outlet of the cathode pipeline, and the fifth solenoid valve and the sixth solenoid valve are arranged at the outlet of the anode pipeline.

[0011] Preferably, the first solenoid valve is arranged between the second temperature and humidity sensor and the outlet of the cathode pipeline, the second solenoid valve is arranged between the second temperature and humidity sensor and the first heating module, the third solenoid valve is arranged between the third temperature and humidity sensor and the third flow sensor, the fourth solenoid valve is arranged between the third temperature and humidity sensor and the first cooling module, the fifth solenoid valve is arranged between the sixth temperature and humidity sensor and the seventh flow sensor, and the sixth solenoid valve is arranged between the sixth temperature and humidity sensor and the second cooling module.

[0012] Preferably, the outlet of the cathode pipeline is connected in parallel with the first heating module, the third temperature and humidity, the first cooling module, and the fourth flow sensor; the third flow sensor is connected in parallel with the first cooling module and the fourth flow sensor; the second cooling module and the eighth flow sensor are connected in parallel with the seventh flow sensor and the third cooling module.

[0013] A method for real-time nitrogen and water management of a battery, using the above-mentioned device, comprises the following steps:

[0014] S1: Ventilate the cathode and anode of the battery through the gas supply unit;

[0015] S2: Record the readings of the temperature and humidity sensors and flow sensors at the anode and cathode inlets of the battery, and calculate the water vapor flow rate Qa,i kg / s of the anode pipeline and the water vapor flow rate Qc,i kg / s of the cathode pipeline;

[0016] S3: In the cathode pipeline, if the second temperature and humidity sensor indicates that the relative humidity is less than 100%, the first solenoid valve is opened and the water vapor flow rate Qc,o1 of the cathode pipeline is calculated; if the second temperature and humidity sensor indicates that the relative humidity is 100%, the second solenoid valve is opened, the gas first passes into the first heating module, and the third solenoid valve is opened. If the third temperature and humidity sensor indicates that the water vapor has reached a saturated state, the water vapor flow rate Qc,o2 at the outlet of the cathode pipeline is calculated using the third flow sensor. If the third temperature and humidity sensor indicates that the water vapor has not reached a saturated state, the fourth solenoid valve is opened, the third solenoid valve is closed, and the water flow rate Qc,o2 at the outlet of the cathode pipeline is calculated using the fourth flow sensor;

[0017] S4: In the anode pipeline, open the fifth solenoid valve. If the fifth temperature and humidity sensor shows that the relative humidity is less than 100%, calculate the water vapor flow rate Qa,o1 through the readings of the sixth flow sensor and the fifth temperature and humidity sensor; if the fifth temperature and humidity sensor shows that the relative humidity is 100% and the sixth flow sensor after the second heating module shows that the relative humidity is less than 100%, then calculate the water vapor flow rate Qa,o2 of the anode pipeline through the seventh flow sensor, and then pass through the second cooling module; if the sixth flow sensor after the second heating module shows that the relative humidity is equal to 100%, close the fifth solenoid valve, open the sixth solenoid valve, the gas passes through the third cooling module, calculate the water vapor content Qa,o2 in the anode pipeline through the eighth flow sensor, and the gas passes through the hydrogen concentration sensor to measure that the hydrogen concentration is a%, then the nitrogen concentration is B = 1 - a%;

[0018] S5: The water flow rate generated in the anode pipeline is A = Qa,o2 - Qa,i, and the water flow rate generated in the cathode pipeline is C = Qc,o2 - Qc,i;

[0019] S6: Collect liquid water at the tail gas outlets of the cathode pipeline and the anode pipeline, and measure the conductivity D in the liquid water.

[0020] Preferably, the water generated by the internal reaction of the battery is S g / s, the water flow rate in the anode pipeline is A, and the water flow rate in the cathode pipeline is C. If A + C = S, the battery is in a water balance state. If A + C < S, water accumulation occurs inside the battery, causing flooding. If A + C > S, the battery is too dry inside. The error between A and Ka is not more than 10%, and the error between C and Kc is not more than 10%. Here, Ka and Kc are preset values used to judge whether the anode and cathode of the fuel cell are flooded or the membrane is dry, obtained through experimental calibration. The Ka and Kc values of fuel cells with different stack sizes are different, but the Ka and Kc values of fuel cells with the same stack size are the same.

[0021] Preferably, the nitrogen concentration B does not exceed 2% - 10%, and the conductivity D does not exceed 0.1 - 5 us / cm.

[0022] Among them, the calculation method of the water vapor flow rate Q is Q = (e * RH * V) / (100 * R * T), where T is the temperature measured by the temperature and humidity sensor, e is the saturated vapor pressure at this temperature, RH is the relative humidity value feedback by the temperature and humidity sensor, R is the gas constant of water vapor, and its value is 461.5. V is the volume flow rate measured by the flow sensor, and the unit is m3 / s.

[0023] The implementation of the technical solution of the present invention can solve the technical problem of valley peak light weakness in the existing technology. The implementation of the technical solution of the present invention can accurately and real-timely measure and monitor the water management of the anode and nitrogen management of the fuel cell cathode without affecting the operation of the fuel cell stack. At the same time, the attenuation of the membrane electrode can be determined by measuring the conductivity of the tail water. By real-time monitoring of key parameters, it is possible to timely judge conditions that may deteriorate the performance and life of the fuel cell, thereby improving the stability and durability of the fuel cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only one embodiment of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Identical components are denoted by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "upper," and "lower" used in the following description refer to directions in the accompanying drawings, and the terms "bottom," "top," "inner," and "outer" refer to directions toward or away from the geometric center of a particular component, respectively.

[0026] Figure 1 Schematic diagram of the device structure;

[0027] Figure 2 This is a schematic diagram of the real-time management process of nitrogen water.

[0028] In the above drawings, the figure numbers represent:

[0029] 1 air supply unit

[0030] 2First flow sensor

[0031] 3. First temperature and humidity sensor

[0032] 4 Second flow sensor

[0033] 5. Second temperature and humidity sensor

[0034] 6First solenoid valve

[0035] 7 Second solenoid valve

[0036] 8. First heating module

[0037] 9Third temperature and humidity sensor

[0038] 10Third solenoid valve

[0039] 11Fourth solenoid valve

[0040] 12Third flow sensor

[0041] 13. First cooling module

[0042] 14 Fourth flow sensor

[0043] 15 data acquisition units

[0044] 16 data processing units

[0045] 17 Hydrogen concentration sensor

[0046] 18 Eighth flow sensor

[0047] 19Third cooling module

[0048] 20 Seventh flow sensor

[0049] 21 Second cooling module

[0050] 22 Fifth solenoid valve

[0051] 23 Sixth solenoid valve

[0052] 24th temperature and humidity sensor

[0053] 25 second heating module

[0054] 26 Fifth temperature and humidity sensor

[0055] 27 Sixth flow sensor

[0056] 28th temperature and humidity sensor

[0057] 29 Fifth flow sensor DETAILED DESCRIPTION

[0058] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0059] Example 1

[0060] In a preferred embodiment 1, Figure 1As shown, a device for real-time nitrogen and water management of a battery includes an anode pipeline, a cathode pipeline, a gas supply unit 1, a flow sensor, a temperature and humidity sensor, a hydrogen concentration sensor 17, a data acquisition unit 15 and a data processing unit 16. The anode pipeline is connected to the anode chamber of the battery, and the cathode pipeline is connected to the cathode chamber of the battery. The gas supply unit 1 is connected to the inlet of the anode pipeline and the inlet of the cathode pipeline respectively. The inlet of the anode pipeline, the outlet of the anode pipeline, the inlet of the cathode pipeline and the outlet of the cathode pipeline are all provided with a flow sensor and a temperature and humidity sensor. The outlet of the anode pipeline is also provided with a second cooling module 21, a third cooling module 19 and a second heating module 25. The outlet of the cathode pipeline is provided with a first cooling module 13 and a first heating module 8. The hydrogen concentration sensor 17 is provided at the outlet of the anode pipeline. The flow sensor, temperature and humidity sensor, and hydrogen concentration sensor 17 are connected to the data acquisition unit 15, and the data processing unit 16 is connected to the data acquisition unit 15.

[0061] In a specific embodiment 1, the nitrogen and water content of the battery can be managed in real time, allowing timely assessment of stack conditions that could deteriorate fuel cell performance and lifespan, thereby improving the stability and durability of the fuel cell. Without affecting stack operation, the device assesses the fuel cell's water management by real-time monitoring of the increase in water at the anode and cathode outlets. Nitrogen accumulation at the anode is measured by measuring the nitrogen concentration at the anode outlet. The conductivity of cooled liquid water at the anode and cathode outlets is measured to assess the ion concentration in the water and assess proton membrane attenuation. Gas is introduced into the anode and cathode of the battery. A gas supply unit 1 connects the anode and cathode chambers of the battery, introducing a mixture of water vapor and hydrogen into the anode and a mixture of water vapor and air into the cathode. The gas supply unit 1 also heats and humidifies the gas. Flow sensors and temperature and humidity sensors are installed at the inlets and outlets of the anode and cathode pipelines, respectively. The flow sensors can detect the gas flow rate in the pipelines, while the temperature and humidity sensors can detect the relative humidity (RH) of the gas. The flow sensors include a first flow sensor 2, a second flow sensor 4, a third flow sensor 12, a fourth flow sensor 14, a fifth flow sensor 29, a sixth flow sensor 27, a seventh flow sensor 20, and an eighth flow sensor 18. Flow sensors are respectively provided at the inlet and outlet of the anode pipeline to ensure real-time detection of the gas flow in the pipeline. The temperature and humidity sensors include a first temperature and humidity sensor 3, a second temperature and humidity sensor 5, a third temperature and humidity sensor 9, a fourth temperature and humidity sensor 28, a fifth temperature and humidity sensor 26, and a sixth temperature and humidity sensor 23. Temperature and humidity sensors are provided at different locations in the anode pipeline and the cathode pipeline to detect the relative humidity of the gas at different locations in the pipeline. Electromagnetic valves are provided at the outlets of the anode pipeline and the cathode pipeline. By adjusting the electromagnetic valves, the opening and closing of different pipelines can be switched, ensuring the maximum accuracy of the relevant data detection, and enabling real-time and accurate detection of the nitrogen and water in the battery. The outlet of the anode pipeline and the outlet of the cathode pipeline are also provided with a cooling module and a heating module. The first cooling module 13 is provided at the outlet of the cathode pipeline to condense the water vapor in the pipeline and then remove the moisture in the exhaust gas. The second cooling module 21 and the third cooling module 19 are provided at the outlet of the anode pipeline to condense the water vapor in the gas. The outlet of the anode pipeline and the outlet of the cathode pipeline are both provided with a heating module. The heating module can increase the relative humidity value of the gas to achieve more accurate measurement of relevant data. A hydrogen concentration sensor 17 is also provided at the outlet of the anode pipeline. The gas at the anode contains nitrogen and hydrogen. After the moisture is discharged, the gas passes through the hydrogen concentration sensor 17 to detect the hydrogen concentration, and then the nitrogen concentration can be calculated, thereby realizing real-time monitoring and management of nitrogen.The flow sensor, temperature and humidity sensor, and hydrogen concentration sensor 17 are connected to the data acquisition unit 15. The data acquisition unit 15 directly collects data from the relevant sensors. The data acquisition unit 15 is also connected to the data processing unit 16. The data processing unit 16 stores a preset algorithm. By calculating the collected data, the real-time nitrogen and water status of the battery is obtained, and the battery stack status that may deteriorate the performance and life of the fuel cell is judged in a timely manner.

[0062] In a preferred embodiment, the flow sensor includes a first flow sensor 2, a second flow sensor 4, a third flow sensor 12, a fourth flow sensor 14, a fifth flow sensor 29, a sixth flow sensor 27, a seventh flow sensor 20 and an eighth flow sensor 18, the first flow sensor 2 is arranged at the inlet of the cathode pipeline, the second flow sensor 4, the third flow sensor 12 and the fourth flow sensor 14 are arranged at the outlet of the cathode pipeline, the fifth flow sensor 29 is arranged at the inlet of the anode pipeline, the sixth flow sensor 27, the seventh flow sensor 20 and the eighth flow sensor 18 are arranged at the outlet of the anode pipeline, and the temperature and humidity sensor includes a first temperature and humidity sensor 3, a second temperature and humidity sensor 5, a third temperature and humidity sensor 9, a fourth temperature and humidity sensor 28, a fifth temperature and humidity sensor 26 and a sixth temperature and humidity sensor 23, the first temperature and humidity sensor 3 is arranged at the inlet of the cathode pipeline, the second temperature and humidity sensor 5 and the third temperature and humidity sensor 9 are arranged at the outlet of the cathode pipeline, the fourth temperature and humidity sensor 28 is arranged at the inlet of the anode pipeline, and the fifth temperature and humidity sensor 26 and the sixth temperature and humidity sensor 23 are arranged at the outlet of the anode pipeline.

[0063] In this specific embodiment, the flow sensor can be used to detect the flow rate of the gas in the pipeline, and the temperature and humidity sensor can be used to detect the relative humidity value RH of the gas. The flow sensor includes a first flow sensor 2, a second flow sensor 4, a third flow sensor 12, a fourth flow sensor 14, a fifth flow sensor 29, a sixth flow sensor 27, a seventh flow sensor 20, and an eighth flow sensor 18. The flow sensors are respectively set at the inlet and outlet of the anode pipeline to ensure real-time detection of the gas flow in the pipeline. The temperature and humidity sensor includes a first temperature and humidity sensor 3, a second temperature and humidity sensor 5, a third temperature and humidity sensor 9, a fourth temperature and humidity sensor 28, a fifth temperature and humidity sensor 26, and a sixth temperature and humidity sensor 23. The temperature and humidity sensors are set at different positions in the anode pipeline and the cathode pipeline, so that the relative humidity value of the gas can be detected at different positions in the pipeline.

[0064] In a preferred embodiment, the gas supply unit 1 includes a cathode gas supply module and an anode gas supply module. The cathode gas supply module is connected to the inlet of the cathode pipeline, and the anode gas supply module is connected to the inlet of the anode pipeline.

[0065] In this specific embodiment, the gas supply unit 1 is connected to the anode chamber and the cathode chamber of the battery, and a mixed gas of water vapor and hydrogen is introduced into the anode, and a mixed gas of water vapor and air is introduced into the cathode. At the same time, the gas supply unit 1 can heat and humidify the gas.

[0066] In a preferred embodiment, the cathode gas supply module provides a mixed gas of air and water vapor, and the anode gas supply module provides a mixed gas of hydrogen and water vapor.

[0067] In this specific embodiment, air and water vapor are introduced into the cathode to measure and calculate the water in the cathode. Nitrogen is generated at the anode during the battery reaction, and the water and nitrogen at the anode can be accurately measured through hydrogen and water vapor.

[0068] In a preferred embodiment, it also includes a first electromagnetic valve 6, a second electromagnetic valve 7, a third electromagnetic valve 10, a fourth electromagnetic valve 11, a fifth electromagnetic valve 22 and a sixth electromagnetic valve 23. The first electromagnetic valve 6, the second electromagnetic valve 7, the third electromagnetic valve 10 and the fourth electromagnetic valve 11 are arranged at the outlet of the cathode pipeline, and the fifth electromagnetic valve 22 and the sixth electromagnetic valve 23 are arranged at the outlet of the anode pipeline.

[0069] In this specific embodiment, electromagnetic valves are provided at the outlets of the anode pipeline and the cathode pipeline. By adjusting the electromagnetic valves, the opening and closing conversion of different pipelines is achieved, ensuring the maximum accuracy of the relevant data detection, and the nitrogen water in the battery can be detected in real time and accurately.

[0070] In a preferred embodiment, the first solenoid valve 6 is arranged between the second temperature and humidity sensor 5 and the outlet of the cathode pipeline, the second solenoid valve 7 is arranged between the second temperature and humidity sensor 5 and the first heating module 8, the third solenoid valve 10 is arranged between the third temperature and humidity sensor 9 and the third flow sensor 12, the fourth solenoid valve 11 is arranged between the third temperature and humidity sensor 9 and the first cooling module 13, the fifth solenoid valve 22 is arranged between the sixth temperature and humidity sensor 23 and the seventh flow sensor 20, and the sixth solenoid valve 23 is arranged between the sixth temperature and humidity sensor 23 and the second cooling module 21.

[0071] In this embodiment, cooling and heating modules are also provided at the outlets of the anode and cathode circuits. A first cooling module 13 is provided at the outlet of the cathode circuit to condense water vapor in the circuit, thereby removing moisture from the exhaust gas. A second cooling module 21 and a third cooling module 19 are provided at the outlet of the anode circuit to also condense water vapor in the gas. Both the outlets of the anode and cathode circuits are equipped with heating modules, which can increase the relative humidity of the gas, thereby enabling more accurate measurement of relevant data.

[0072] In a preferred embodiment, the outlet of the cathode pipeline is connected in parallel with the first heating module 8, the third temperature and humidity 9, the first cooling module 13, and the fourth flow sensor 14, the third flow sensor 12 is connected in parallel with the first cooling module 13 and the fourth flow sensor 14, and the second cooling module 21 and the eighth flow sensor 18 are connected in parallel with the seventh flow sensor 17 and the third cooling module 19.

[0073] In this specific embodiment, different parallel pipelines are provided at the outlet of the anode pipeline and the outlet of the cathode pipeline, so that different pipelines can be switched under different conditions, thereby achieving accurate measurement of relevant data.

[0074] Example 2

[0075] In a preferred embodiment 2, Figure 2 As shown, a method for real-time nitrogen and water management of a battery, using the above-mentioned device, comprises the following steps:

[0076] S1: Ventilate the cathode and anode of the battery through the gas supply unit 1;

[0077] S2: Record the readings of the temperature and humidity sensors and flow sensors at the anode and cathode inlets of the battery, and calculate the water vapor flow rate Qa,i kg / s of the anode pipeline and the water vapor flow rate Qc,i kg / s of the cathode pipeline;

[0078] S3: In the cathode pipeline, if the second temperature and humidity sensor indicates that the relative humidity is less than 100%, the first solenoid valve is opened and the water vapor flow rate Qc,o1 of the cathode pipeline is calculated; if the second temperature and humidity sensor indicates that the relative humidity is 100%, the second solenoid valve is opened, the gas first passes into the first heating module, the third solenoid valve is opened, and if the third temperature and humidity sensor indicates that the water vapor has reached a saturated state, the water vapor flow rate Qc,o2 at the outlet of the cathode pipeline is calculated using the third flow sensor; if the third temperature and humidity sensor indicates that the water vapor has not reached a saturated state, the fourth solenoid valve is opened, the third solenoid valve is closed, and the water flow rate Qc,o2 at the outlet of the cathode pipeline is calculated using the fourth flow sensor;

[0079] S4: In the anode pipeline, the fifth solenoid valve is opened. If the relative humidity is less than 100%, the water vapor flow rate Qa,o1 is calculated by the readings of the sixth flow sensor and the fourth temperature and humidity sensor. If the relative humidity is 100%, if the sixth flow sensor after the second heating module shows that the relative humidity is less than 100%, the water vapor flow rate Qa,o2 of the anode pipeline is calculated by the seventh flow sensor, and then passes through the second cooling module. If the sixth flow sensor after the second heating module shows that the relative humidity is equal to 100%, the fifth solenoid valve is closed, the sixth solenoid valve is opened, the gas passes through the third cooling module, and the water vapor content Qa,o2 in the anode pipeline is calculated by the eighth flow sensor. The gas passes through the hydrogen sensor to measure the hydrogen concentration to be a%, and the nitrogen concentration is B=1-a%.

[0080] S5: The water flow rate generated by the anode pipeline is A = Qa,o2 - Qa,i, and the water flow rate generated by the cathode pipeline is C = Qc,o2 - Qc,i;

[0081] S6: Collect liquid water at the tail gas outlets of the cathode pipeline and the anode pipeline, and measure the conductivity D in the liquid water.

[0082] In specific embodiment 2, gas is introduced into the anode and cathode of the battery. The cathode inlet of the battery is a mixture of air and water vapor, and the anode inlet is a mixture of hydrogen and water vapor. The water content of the humidified gas at the anode and cathode inlets is calculated using the measurements of the first flow sensor 2, the fifth flow sensor 29, the first temperature and humidity sensor 3, and the fourth temperature and humidity sensor 28 at the anode and cathode inlets, respectively. The anode water vapor flow rate is Qa,i kg / s, and the cathode water vapor flow rate is Qc,i kg / s. The water vapor flow rate Q is calculated as Q = (e * RH * V) / (100 * R * T), where T is the temperature measured by the temperature and humidity sensor, e is the saturated vapor pressure at that temperature, RH is the relative humidity value fed back by the temperature and humidity sensor, and R is the gas constant for water vapor, which is 461.5. V is the volume flow rate measured by the flow sensor in m³ / s.

[0083] The gas at the cathode outlet of the battery is a mixture of air (excess) and water vapor. The mixed gas first passes through the second flow sensor 4 and the second temperature and humidity sensor 5. (1) If the second temperature and humidity sensor 5 shows that the relative humidity of the gas is less than 100%, it means that there is no water vapor in the mixed gas. The first electromagnetic valve 6 opens to discharge the cathode tail gas. The outlet water vapor flow rate Qc,o1 of the cathode pipeline is calculated, where T and RH are the temperature and relative humidity measured by the outlet temperature and humidity sensor respectively; (2) If the second temperature and humidity sensor 5 shows that the relative humidity of the gas is 100%, it means that there is water vapor in the mixed gas. At this time, the second electromagnetic valve 7 is opened, and the mixed gas first passes into the first heating module 8 and is heated to the temperature Td. If the third temperature and humidity sensor 9 shows that the water vapor has reached saturation at this time, the water vapor flow rate Qc,o2 at the cathode outlet is calculated by the third flow sensor 12. If the second temperature and humidity sensor 5 indicates the relative humidity is less than 100%, the third solenoid valve 10 is closed and the fourth solenoid valve 11 is opened. The first cooling module 13 is used to convert all the water vapor in the mixed gas into liquid water. Because the water vapor content in the mixed gas is high at this point and the dew point temperature has not yet been reached when the temperature reaches Td, the water vapor in the mixed gas is converted to liquid water. The fourth flow sensor 14 then measures the water flow rate Qc,o2 at the cathode outlet. Qc,o2 - Qc,o1 represents the liquid water flow rate in the mixed gas, while Qc,o1 represents the gaseous water flow rate. The gaseous portion accounts for X1 = Qc,o1 / Qc,o2, and the liquid portion accounts for X2 = 1 - Qc,o1 / Qc,o2. When the RH is less than 100, Qc,o1 = Qc,o2.

[0084] The anode pipeline outlet gas is a mixture of nitrogen, hydrogen, and water vapor. The gas passes through the fifth flow sensor 19 and the fourth temperature and humidity sensor 28. The water vapor flow rate Qa,o1 is calculated based on the data. If the relative humidity RH is less than 100%, all water exists in a gaseous state, and the water flow rate at the anode pipeline outlet is Qa,o1. If the relative humidity RH is 100%, the mixed gas first passes through the second heating module 25 and is heated to temperature Td. If the sixth temperature and humidity sensor 23 indicates that the water vapor has reached saturation, the anode pipeline outlet water vapor flow rate Qa,o2 is calculated based on the data from the seventh flow sensor 20. Finally, the water in the mixed gas is removed by the third cooling module 19. If the sixth temperature and humidity sensor 23 indicates that the water vapor has not reached saturation, the gas passes through the second cooling module 21 to convert all the water vapor into liquid water. The eighth flow sensor 18 measures the liquid water flow rate Qa,o2. If RH is equal to 100, the anode outlet water flow (including gaseous and liquid) is Qa,o2, where gaseous accounts for Y1 = Qa,o1 / Qa,o2 and liquid accounts for Y2 = 1-Qa,o1 / Qa,o2. When RH is less than 100, Qa,o1 = Qa,o2.

[0085] After cooling, the anode mixed gas is filtered to remove liquid water. The mixed gas is a mixture of nitrogen and hydrogen. The mixed gas passes through the hydrogen concentration sensor 17, and the hydrogen concentration sensor 17 measures the hydrogen concentration a% in the mixed gas. The anode nitrogen concentration B = 1 - a%.

[0086] The flow rate of the water generated at the cathode can be expressed as C = Qc,o2 - Qc,i, and the water generated at the anode can be expressed as A = Qa,o2 - Qa,i.

[0087] The water generated by the internal reaction of the battery is S g / s. If A + C = S, the fuel cell is in a water balance state, and all the water generated by the reaction is discharged. If A + C < S, the water generated by the fuel cell reaction is not discharged in time and accumulates inside the fuel cell, causing flooding. If A + C > S, the inside of the fuel cell may be too dry. In the water balance state, that is, A + C = S, the increase in anode water A should be equal to Ka, and the increase in cathode water C should be equal to Kc. The error between A and Ka (C and Kc) should not exceed 10%. Here, Ka and Kc are preset values used to judge whether the anode and cathode of the fuel cell are flooded or the membrane is dry, obtained through experimental calibration. The Ka and Kc values of fuel cells with different stack sizes are different, but the Ka and Kc values of fuel cells with the same stack size are the same. Before detecting the flooding and membrane dryness of the fuel cell, it is necessary to measure the Ka and Kc of the battery. If the battery is in a flooded state, that is, A + C < S, if A < Ka, it indicates that the anode is flooded, and if C < Kc, it indicates that the cathode is flooded. When the battery is in an over-dry state, that is, A + C > S, if A > Ka, it indicates that the anode is over-dry, and if C > Kc, it indicates that the cathode is over-dry. The anode nitrogen concentration B should be less than the constant Kn, and the value range of Kn is 2% - 10%. Liquid water can be collected at the anode and cathode exhaust ports. By analyzing the ion content in the water, the attenuation of the membrane electrode can be judged. The conductivity D of the collected water should be lower than the constant Ki, and the value range of Ki is 0.1 - 5 us / cm.

[0088] In a preferred embodiment, the water generated by the internal reaction of the battery is S g / s, the water flow rate in the anode pipeline is A, and the water flow rate in the cathode pipeline is C. If A + C = S, the battery is in a water balance state. If A + C < S, water accumulates inside the battery, causing flooding. If A + C > S, the inside of the battery is over-dry. The error between A and Ka is not greater than 10%, and the error between C and Kc is not greater than 10%.

[0089] In this embodiment, the data processing unit 16 processes the data of the data acquisition unit 15 and displays the processing result. Specifically, the flow rate of water generated at the cathode can be expressed as C = Qc,o2 - Qc,i, and the water generated at the anode can be expressed as A = Qa,o2 - Qa,i. The water generated by the internal reaction of the battery is S g / s. If A + C = S, the fuel cell is in a water balance state, and all the water generated by the reaction is discharged. If A + C < S, the water generated by the fuel cell reaction is not discharged in time and accumulates inside the fuel cell, causing flooding. If A + C > S, the inside of the fuel cell may be over-dry. In the water balance state, that is, A + C = S, the increase in anode water A should be equal to Ka, and the increase in cathode water C should be equal to Kc. The error between A and Ka (C and Kc) should not exceed 10%. If the battery is in a flooded state, that is, A + C < S, if A < Ka, it indicates that the anode is flooded, and if C < Kc, it indicates that the cathode is flooded. When the battery is in an over-dry state, that is, A + C > S, if A > Ka, it indicates that the anode is over-dry, and if C > Kc, it indicates that the cathode is over-dry. The anode nitrogen concentration B should be less than the constant Kn, and the value range of Kn is 2% - 10%. Liquid water can be collected at the anode and cathode exhaust ports. By analyzing the ion content in the water, the attenuation of the membrane electrode can be judged. The conductivity D of the collected water should be lower than the constant Ki, and the value range of Ki is 0.1 - 5 us / cm.

[0090] In a preferred embodiment, the nitrogen concentration B does not exceed 2% - 10%, and the conductivity D does not exceed 0.1 - 5 us / cm.

[0091] In this specific embodiment, by collecting the water discharged from the cathode and anode and detecting the ion concentration in the water, the attenuation of the proton membrane can be obtained.

[0092] It should be noted that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A device for real-time nitrogen and water management of a battery, characterized by: It includes an anode pipeline, a cathode pipeline, an electromagnetic valve, an air supply unit, a flow sensor, a temperature and humidity sensor, a hydrogen concentration sensor, a data acquisition unit and a data processing unit. The anode pipeline is connected to the anode chamber of the battery, and the cathode pipeline is connected to the cathode chamber of the battery. The air supply unit is connected to the inlet of the anode pipeline and the inlet of the cathode pipeline respectively. The inlet of the anode pipeline, the outlet of the anode pipeline, the inlet of the cathode pipeline and the outlet of the cathode pipeline are all provided with the flow sensor and the temperature and humidity sensor. The outlet of the anode pipeline is also provided with a second cooling module, a third cooling module and a second heating module. , a first cooling module and a first heating module are provided at the outlet of the cathode pipeline, the hydrogen concentration sensor is provided at the outlet of the anode pipeline, the electromagnetic valves are provided at the outlets of the anode pipeline and the cathode pipeline respectively, the flow sensor, the temperature and humidity sensor, and the hydrogen concentration sensor are connected to the data acquisition unit, and the data processing unit is connected to the data acquisition unit; the flow sensor includes a first flow sensor, a second flow sensor, a third flow sensor, a fourth flow sensor, a fifth flow sensor, a sixth flow sensor, a seventh flow sensor and an eighth flow sensor, the first flow sensor A flow sensor is arranged at the inlet of the cathode pipeline, the second flow sensor, the third flow sensor and the fourth flow sensor are arranged at the outlet of the cathode pipeline, the fifth flow sensor is arranged at the inlet of the anode pipeline, the sixth flow sensor, the seventh flow sensor and the eighth flow sensor are arranged at the outlet of the anode pipeline, the temperature and humidity sensor includes a first temperature and humidity sensor, a second temperature and humidity sensor, a third temperature and humidity sensor, a fourth temperature and humidity sensor, a fifth temperature and humidity sensor and a sixth temperature and humidity sensor, the first temperature and humidity sensor is arranged at the inlet of the cathode pipeline, the second temperature and humidity sensor and the third temperature and humidity sensor are arranged at the outlet of the cathode pipeline, the fourth temperature and humidity sensor is arranged at the inlet of the anode pipeline, the fifth temperature and humidity sensor and the sixth temperature and humidity sensor are arranged at the outlet of the anode pipeline; the outlet of the cathode pipeline is connected in parallel with the first heating module, the third temperature and humidity sensor, the first cooling module and the fourth flow sensor, the third flow sensor is connected in parallel with the first cooling module and the fourth flow sensor, the second cooling module and the eighth flow sensor are connected in parallel with the seventh flow sensor and the third cooling module.

2. The device for real-time nitrogen and water management of a battery according to claim 1, characterized in that: The gas supply unit includes a cathode gas supply module and an anode gas supply module. The cathode gas supply module is connected to the inlet of the cathode pipeline, and the anode gas supply module is connected to the inlet of the anode pipeline.

3. The device for real-time nitrogen and water management of a battery according to claim 2, characterized in that: The cathode gas supply module provides a mixed gas of air and water vapor, and the anode gas supply module provides a mixed gas of hydrogen and water vapor.

4. The device for real-time nitrogen and water management of a battery according to claim 3, characterized in that: The solenoid valve includes a first solenoid valve, a second solenoid valve, a third solenoid valve, a fourth solenoid valve, a fifth solenoid valve and a sixth solenoid valve. The first solenoid valve, the second solenoid valve, the third solenoid valve and the fourth solenoid valve are arranged at the outlet of the cathode pipeline, and the fifth solenoid valve and the sixth solenoid valve are arranged at the outlet of the anode pipeline.

5. The device for real-time nitrogen and water management of a battery according to claim 4, characterized in that: The first solenoid valve is arranged between the second temperature and humidity sensor and the outlet of the cathode pipeline, the second solenoid valve is arranged between the second temperature and humidity sensor and the first heating module, the third solenoid valve is arranged between the third temperature and humidity sensor and the third flow sensor, the fourth solenoid valve is arranged between the third temperature and humidity sensor and the first cooling module, the fifth solenoid valve is arranged between the sixth temperature and humidity sensor and the seventh flow sensor, and the sixth solenoid valve is arranged between the sixth temperature and humidity sensor and the second cooling module.

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