Method for calculating real-time hydrogen storage amount and residual endurance mileage of fuel cell vehicle

Abstract

The invention discloses a method for calculating the real-time hydrogen storage amount and the remaining endurance mileage of a fuel cell vehicle, and belongs to the solid hydrogen storage amount measurement technology of a fuel cell. The method comprises the following steps: firstly, carrying out calibration and cycle test analysis on a hydrogen storage material, including establishing relationships between hydrogen storage capacity, temperature and pressure in a full life cycle of a fuel cell stack; the initial hydrogen storage amount is obtained when the vehicle is started, and the obtaining mode comprises the steps that the temperature of the hydrogen storage device and pressure sensor data are read based on the FCU to convert and calculate the initial hydrogen storage amount; when the vehicle runs, the hydrogen consumption amount of the fuel cell stack and the remaining hydrogen storage amount in the hydrogen storage device are calculated in real time, the remaining endurance mileage is calculated in real time on the basis of the remaining hydrogen storage amount, and calculation includes calculation based on the driving mileage within the time t1 to t2 and the hydrogen consumption amount. The method can overcome the defect that in the prior art, the error of estimating the hydrogen storage amount based on thermodynamics in the vehicle running process is too large, the estimation precision of the real-time hydrogen storage amount in the hydrogen storage device is improved, application of hydrogen energy to new energy vehicles, ships and aircrafts can be promoted, and precise prediction of endurance is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrogen energy storage, and particularly relates to a method for calculating the real-time hydrogen storage amount and remaining cruising range of a fuel cell vehicle. Background Art

[0002] Solid-state hydrogen storage technology is considered to be an important development direction for future hydrogen energy storage due to its advantages such as high safety and high hydrogen storage density. However, how to accurately estimate the remaining hydrogen amount in a solid-state hydrogen storage cylinder has always been a major problem restricting its wide application. Currently, the main methods for estimating the remaining hydrogen amount in a solid-state hydrogen storage cylinder are as follows:

[0003] Pressure method: Indirectly calculate the remaining hydrogen amount by measuring the pressure change in the hydrogen storage cylinder. However, since the hydrogen absorption and desorption characteristics of the solid-state hydrogen storage material and the pressure are not linearly related and are easily affected by temperature, the accuracy is low. Moreover, the pressure method can only evaluate the hydrogen storage amount of the hydrogen cylinder in a static state of the system. In a dynamic state of the system, that is, when hydrogen is continuously consumed and converted into vehicle power, the temperature and pressure of the hydrogen storage system change frequently, and it cannot be used to evaluate the real-time remaining hydrogen amount during the operation of the system.

[0004] Flow method: Cumulatively calculate the remaining hydrogen amount by measuring the hydrogen flow rate in and out of the hydrogen storage cylinder. However, this method requires an accurate flow sensor and is easily affected by factors such as leakage, making it difficult to ensure long-term accuracy. The mass flowmeter of gas has a high cost and is not suitable for the application of small low-cost systems, such as hydrogen-powered vehicles. Finally, the flow method itself requires a clear record of the hydrogen storage history of the hydrogen cylinder, which is not applicable to application scenarios with multi-path and multi-site hydrogen refueling, such as hydrogen vehicle rental and bottle replacement services.

[0005] Heat method: Indirectly calculate the remaining hydrogen amount by measuring the thermal effect during the hydrogen absorption and desorption process of the hydrogen storage cylinder. However, this method requires an accurate heat sensor and is easily affected by factors such as ambient temperature, with a high cost and is not suitable for evaluating the hydrogen storage amount during the operation of low-cost vehicles.

[0006] In addition, during the operation of a hydrogen fuel cell vehicle, hydrogen continuously releases from the solid material and absorbs heat. Because the heat absorption and hydrogen desorption are in a kinetic process, the heat transfer process between the system and the environment is also affected by various factors. Therefore, there is no steady-state equilibrium in the thermodynamic sense between hydrogen and the solid material. In addition, the prior art cannot provide the driver with the real-time hydrogen state according to the operating conditions and cannot provide real-time cruising range information. Summary of the Invention

[0007] The present invention aims to provide a method for calculating the real-time hydrogen storage amount and remaining cruising range of a fuel cell vehicle to overcome the deficiency of excessive error in estimating the hydrogen storage amount based on thermodynamics during the operation of the vehicle in the prior art.

[0008] Technical solution: A method for calculating the real-time hydrogen storage capacity and remaining driving range of a fuel cell vehicle, and the steps of this method include:

[0009] (1) Calibrate the hydrogen storage device and conduct charge and discharge cycle test analysis during its entire life cycle to obtain the initial hydrogen storage capacity C p 0 and the relationships between the hydrogen storage capacity in each cycle and the temperature, pressure, including the hydrogen state, it is in;

[0010] (2) Considering the attenuation of the hydrogen storage performance of the hydrogen storage device and the hydrogen storage material, introduce a correction factor to estimate the actual hydrogen storage capacity of this hydrogen storage device during this charge and discharge, and the calculation expression is:

[0011] C p n = C p 0 e -kn

[0012] In the formula, n represents the number of cycles, C p n is the measured hydrogen storage capacity after the nth cycle, and k is the attenuation constant, which is determined by PCT curve fitting or cyclic hydrogen absorption and desorption tests;

[0013] (3) Considering the maximum hydrogen escape rate of this hydrogen storage device and the hydrogen loss caused by flushing in the fuel cell system, calculate the hydrogen consumption of the fuel cell stack during this cycle, and the calculation method is as follows:

[0014]

[0015] In the formula, P(t) represents the function of the stack output power changing with time, ε(t) represents the electrochemical efficiency of the stack, t1 and t2 are the start and end times of the fuel cell working during this cycle, C d is the maximum hydrogen escape rate of the hydrogen cylinder and the system, τ is the shutdown time of the system before the most recent startup, C f is the hydrogen loss amount per single flushing;

[0016] (4) Calculation of the remaining hydrogen storage capacity SoE H2 :

[0017] SoE H2 = C p n – C e

[0018] (5) Calculate the remaining driving range based on the remaining hydrogen storage capacity, and this calculation includes calculating based on the mileage traveled and the hydrogen consumption within the time from t1 to t2.

[0019] Further, in step (1), the analysis steps for the influence of the hydrogen storage material on the hydrogen storage capacity are as follows:

[0020] 1) Place the hydrogen storage material in a vacuum container, maintain the hydrogen pressure at 2 - 6 MPa to form a metal hydride compound, then raise the temperature to 300 - 500 °C, and maintain a hydrogen soak for 1 - 10 hours on the high-temperature hydrogen-related platform to promote the formation of α and β crystal form metal hydrides, and complete the soaking treatment;

[0021] 2) Perform an activation cycle treatment on the hydrogen storage material processed in step 1), including subjecting the hydrogen storage material to several absorption - desorption cycles to promote and improve its reaction kinetics, and complete the pretreatment work of the hydrogen storage material by exposing the hydrogen storage material to hydrogen and reducing the pressure to release hydrogen;

[0022] 3) Record the change in hydrogen absorption amount at different pressures for the hydrogen storage capacity of the activated hydrogen storage material at a constant temperature until saturation, and then calculate the hydrogen storage capacity at each pressure point through the mass difference;

[0023] 4) Adjust the temperature and keep it constant for a period of time, while controlling the change in hydrogen pressure, measure the corresponding equilibrium hydrogen content in the material, obtain the isothermal equilibrium line of the hydrogen storage material at different temperatures, including obtaining the relationship between hydrogen pressure and the composition of the hydrogen storage material represented graphically;

[0024] 5) Based on the isothermal line of the hydrogen storage capacity obtained in step 4) and the relationship between the equilibrium hydrogen pressure and the hydrogen storage capacity, construct a PCT model of the hydrogen storage material for mapping the association between temperature and hydrogen pressure within the working temperature range of the material, and obtain the relationship between the pressure and hydrogen storage capacity of this hydrogen storage cylinder.

[0025] Further, the calculation of the initial hydrogen storage capacity in step (2) is achieved based on analyzing the relationship between the hydrogen storage capacity, temperature, and pressure of this hydrogen storage material, including the variable-pressure hydrogen storage capacity and the isothermal equilibrium amount;

[0026] The so-called variable-pressure hydrogen storage capacity refers to measuring the hydrogen storage capacity of the activated hydrogen storage material at a constant temperature, and the so-called isothermal equilibrium amount refers to controlling the change in hydrogen pressure at different temperatures and measuring the corresponding equilibrium hydrogen content in the hydrogen storage material.

[0027] Further, the estimation of the initial hydrogen storage capacity includes obtaining a PCT curve based on the analysis of pressure - composition - temperature of the hydrogen storage material, and this PCT curve can characterize the relationship between hydrogen pressure and hydrogen concentration in the material when the hydrogen storage material absorbs and releases hydrogen at different temperatures;

[0028] This method constructs a PCT model of the hydrogen storage material and fits this model based on the Van't Hoff equation.

[0029] Further, in the calculation of the hydrogen consumption of the fuel cell stack during vehicle operation, when t1 is infinitely close to or equal to t2, the real-time stack hydrogen consumption rate is obtained as follows:

[0030] In this method, the electrochemical efficiency of the stack

[0031] In the formula, V represents the average single-cell voltage of the stack, and P is the output power of the stack.

[0032] Further, this method for calculating the real-time remaining cruising range includes applying to different road sections based on the time scale composed of t1 and t2 and its adjustment, and also includes calculating the real-time driving speed and driving distance of the vehicle through the GPS real-time positioning information; calculating the hydrogen consumption per 100 kilometers during this time period according to the calculated real-time driving speed and driving distance and the power generation of the hydrogen system within a certain time period, and estimating the remaining cruising range.

[0033] Further, the hydrogen escape amount of the hydrogen storage device is equal to the maximum hydrogen escape rate of the hydrogen storage material multiplied by the time estimated since the last shutdown, and the maximum hydrogen escape rate is determined by experiments.

[0034] The present invention also provides a real-time hydrogen storage amount and remaining cruising range display system for a fuel cell vehicle, including:

[0035] A solid-state hydrogen storage device for providing hydrogen to the fuel cell stack;

[0036] A fuel cell controller FCU that acquires data including the pressure sensor and temperature sensor of the hydrogen storage device, and records the cycle times of the hydrogen storage device to obtain the measured hydrogen storage capacity C after the nth cycle p n , and then performs the above-mentioned hydrogen storage amount calculation and remaining mileage calculation.

[0037] Further, the fuel cell controller FCU includes acquiring the temperature of the fuel cell stack and real-time monitoring and collecting the voltage of a single cell of the stack for calculating the real-time stack hydrogen consumption rate.

[0038] Even further, a pressure sensor and a pressure reducing valve are provided on the gas supply pipeline from the hydrogen storage device to the fuel cell stack.

[0039] Beneficial effects: Based on the characteristics of the solid-state hydrogen storage material, the present invention examines the remaining capacity in the hydrogen storage device. Based on the relationship between the remaining hydrogen amount and parameters such as temperature and pressure, the accuracy of estimating the real-time hydrogen state is improved, including considering the maximum hydrogen escape rate and problems such as the gradual increase in the concentration of nitrogen in the anode of the fuel cell due to cathode gas diffusion, resulting in a decrease in hydrogen purity and a reduction in fuel cell efficiency. In the present invention, based on the material PCT model, by collecting and detecting pressure or temperature or the average single-cell voltage of the stack (the electrochemical efficiency of the stack), the influence brought by the detection failure of a single sensor is avoided from multiple angles. Finally, the present invention can also mutually verify whether there is a calculation error in the remaining mileage by detecting and calculating the estimated value and the multiple cycle tests, PCT curves, and power-law decay relationship considering the number of cycles of the hydrogen storage device. Description of the Drawings

[0040] Figure 1 is the PCT isotherm of the hydrogen storage material;

[0041] Figure 2 (a) is the relationship between the hydrogen storage amount and the equilibrium pressure at different temperatures, Figure 2 (b) is the relationship between the equilibrium hydrogen storage amount and temperature (Van't Hoff equation, endothermic reaction);

[0042] Figure 3 is the relationship diagram of the fuel cell stack power, stack efficiency and output current;

[0043] Figure 4 is the structural schematic diagram of the solid-state hydrogen storage - air-cooled fuel cell system in the embodiment. Detailed Embodiments

[0044] The degree of hydrogen adsorption on the hydrogen storage material is an equilibrium between solid hydrogen and gaseous hydrogen. This equilibrium indicates that the amount of hydrogen adsorbed by the solid-state hydrogen storage material in the hydrogen storage device does not represent the maximum release amount, that is, it is not completely released, and is affected by the solid-state hydrogen storage material and temperature and pressure.

[0045] The existing technology generally estimates the hydrogen storage amount based on the adsorption amount of the solid-state hydrogen storage material as the total amount, and then calculates the actual consumption of the vehicle, including estimating the consumption based on the calculation of the generated electric energy, etc., but the generated electric energy does not consider the generation of waste heat. The present invention mainly determines the real-time remaining hydrogen amount or hydrogen storage state in the fuel cell system through the following three aspects.

[0046] 1. Determine the initial hydrogen storage capacity of the hydrogen storage material from the material perspective, and the relationship between the initial hydrogen storage capacity and temperature and pressure. This provides the hydrogen storage performance of the hydrogen cylinder containing the solid-state hydrogen storage material before leaving the factory.

[0047] 2. Determine the hydrogen storage state of the hydrogen cylinder from the perspective of material aging, that is, consider the actual hydrogen storage capacity of the material after the attenuation of the hydrogen storage capacity after the hydrogen absorption and desorption cycles. The actual hydrogen storage capacity gradually decreases with the use of the hydrogen cylinder.

[0048] 3. From the perspective of fuel cell operation, determine the hydrogen consumption in the hydrogen cylinder during operation, and then obtain the real-time remaining hydrogen storage amount. At the same time, considering that the hydrogen storage amount in the hydrogen storage device can be gradually reduced through fuel cell power generation, anode flushing, and hydrogen escape, that is, taking into account the hydrogen escape rate and flushing, and then the real-time remaining hydrogen storage amount is the fundamental basis for calculating the remaining mileage of the vehicle.

[0049] Calculate the remaining mileage of the vehicle based on the actual remaining hydrogen amount of the fuel cell system determined from the above three aspects, and then load it onto the user interface, thereby providing assistance for the operation of the fuel cell vehicle power system.

[0050] The estimation method of the present invention is divided into two parts. The first part is a mathematical model established based on measured data and associated with the characteristics of solid hydrogen storage materials when the fuel cell system is out of service. By measuring parameters such as the temperature and pressure of the hydrogen storage cylinder, the remaining hydrogen amount (initial hydrogen storage amount) in the hydrogen cylinder can be accurately and reliably estimated. The second part is to monitor the single-cell voltage of the fuel cell in real time to estimate the electrochemical efficiency, and estimate the real-time hydrogen consumption of the hydrogen storage module during operation by monitoring the net output power of the DC-DC and the energy consumption for maintaining the pressure of the fuel cell and the hydrogen cylinder. Based on the difference between the initial hydrogen storage amount and the real-time hydrogen consumption, the real-time hydrogen storage amount estimated by the present invention has the advantages of high accuracy, high reliability, and low cost, and is expected to be widely and practically applied in the field of hydrogen energy storage.

[0051] The implementation process of the present invention is further introduced below.

[0052] Calibration is a method for characterizing the equilibrium relationship between pressure, hydrogen concentration, and temperature in a metal hydride system in the laboratory, in order to deeply understand the thermodynamics controlling hydrogen absorption and desorption, develop a mathematical model of hydrogen storage amount and system pressure and temperature, and finally use it to estimate the hydrogen storage amount in the fuel cell system. We first perform calibration on the solid hydrogen storage material in the hydrogen storage device to study and analyze the influence of this material on the hydrogen storage amount. The specific steps are as follows:

[0053] S1. Load the metal hydride sample into the sample chamber, and first remove the surface oxides or impurities that hinder the interaction with hydrogen through the activation process.

[0054] The activation process involves exposing the material to hydrogen gas at high temperature and high pressure to initiate the formation of the desired hydride phase and create pathways for subsequent hydrogen absorption. Through absorption and desorption cycles, the material can further improve its performance by refining the microstructure and enhancing reaction kinetics. Successful activation can increase the hydrogen storage capacity, accelerate kinetics, and enhance reversibility, ultimately unleashing the full potential of the hydrogen storage material.

[0055] S2. After evacuating the sample chamber, introduce hydrogen gas and maintain the hydrogen pressure at 2 - 6 MPa, preferably 3 - 5 MPa, to form a metal hydride compound. Gradually increase the sample temperature to 300 - 500 °C, preferably 350 - 450 °C, and maintain a hydrogen soak for 1 - 10 hours, preferably 4 - 6 hours, on the hydrogen-related high-temperature plateau to promote the formation of α and β crystalline metal hydrides.

[0056] S3. Activation cycle treatment. After the soak period, subject the material to multiple absorption - desorption cycles to further improve its reaction kinetics. This includes repeating 1 - 10 cycles, preferably 2 - 6 cycles, under high pressure, exposing the material to hydrogen gas, and then reducing the pressure to release hydrogen.

[0057] The above steps S1 - S3 complete the performance and impact analysis of the hydrogen storage material. Next, calculate the variable-pressure hydrogen storage capacity and the isothermal equilibrium capacity.

[0058] The variable-pressure hydrogen storage capacity is obtained by measuring the hydrogen storage capacity of the activated hydrogen storage material at a constant temperature and the change in hydrogen absorption amount at different pressures until saturation is reached, and a curve graph of the pressure and hydrogen absorption amount change (PCT isotherm of the hydrogen storage material) can be formed, as Figure 1 shown. For the variable-pressure hydrogen storage capacity, calculate the hydrogen storage capacity at each pressure point by the mass difference (weighing method).

[0059] The isothermal equilibrium capacity. At a certain constant temperature, control the systematic change of the hydrogen pressure and accurately measure the corresponding equilibrium hydrogen content in the material. Figure 1 This shows the relationship between pressure and hydrogen storage amount at 25 °C. Then adjust the temperature and continue to control the change of the hydrogen pressure. This process will generate isothermal equilibrium lines at different temperatures, graphically representing the pressure - composition relationship at that specific temperature.

[0060] Combining the analysis of the variable-pressure hydrogen storage capacity and the isothermal equilibrium capacity, we can further consider using the PCT model of the hydrogen storage material to facilitate the calculation and analysis of the initial hydrogen storage amount, which can be combined with Figure 2 (a) and Figure 2 (b) for analysis.

[0061] a. Gradually adjust the temperature and repeat the isothermal equilibrium measurement process to generate a series of PCT models or isotherms of hydrogen storage capacity for mapping the relationship between temperature and hydrogen pressure within the operating temperature range of the material, i.e., the Van't Hoff equation, whose expression is:

[0062]

[0063] where ΔH: enthalpy change (negative for hydrogen absorption and positive for hydrogen desorption, J / mol); ΔS: entropy change (J / (mol·K)); P: equilibrium hydrogen pressure (Pa); R: gas constant (8.314 J / (mol·K)); T: temperature (K).

[0064] Method for analyzing the Van't Hoff equation: Measure the equilibrium hydrogen pressures (P1, P2) between hydrogen and the solid material at different temperatures (T1, T2), and then solve the simultaneous equations to obtain ΔH and ΔS;

[0065] Finally, by plotting

[0066] b. Based on the relationship between the equilibrium hydrogen pressure and the hydrogen storage capacity, establish a mathematical model between the remaining hydrogen quantity C p and parameters such as temperature and pressure. The above calibration process must be repeated for each metal hydride to obtain a targeted PCT model:

[0067] C p = a*ln(P) + b (2);

[0068] where C p is the hydrogen storage capacity (wt%), a and b are fitting parameters, and P is the hydrogen equilibrium pressure (MPa).

[0069] c. After the hydrogen storage system undergoes multiple hydrogen absorption - desorption cycles, the hydrogen storage capacity will decay, and the degree of decay of the hydrogen storage quantity is related to the composition and processing technology of the solid hydrogen storage material. In addition, it is also related to the gradual pulverization and surface oxidation of the material. Therefore, an empirical correction factor needs to be introduced to reduce the theoretical capacity.

[0070] The decay formula adopted in the present invention is:

[0071] C p n = C p 0 e -kn (3)

[0072] where C p n is the capacity after the nth cycle, and the number of hydrogen charging and discharging cycles is recorded by the fuel cell system controller FCU; k is the decay constant, which is related to the pulverization and oxidation of the material, C pn is the initial hydrogen storage capacity. The decay constant k of this formula can be obtained through rapid multi-round cycle experiments.

[0073] For the initial hydrogen storage amount, each time the fuel cell system receives a start command, the controller FCU first estimates the remaining hydrogen capacity of the hydrogen storage system to timely remind the user and the background management personnel of the cruising range. When estimating the remaining hydrogen capacity, the valve of the hydrogen storage cylinder is still closed, that is, no hydrogen leaves the hydrogen storage cylinder. The system reads the temperature and pressure sensor data of the hydrogen storage cylinder through the FCU and inputs the data into the mathematical model pre-stored on the FCU for calculation to obtain the actual hydrogen storage capacity C of the hydrogen cylinder. p n .

[0074] After determining the initial hydrogen storage amount, we consider the real-time hydrogen consumption rate of the stack. During the operation of the fuel cell, while monitoring the temperature and pressure of the hydrogen storage cylinder changing with time, the average single-cell voltage of the stack is monitored. Through the monitored data, the following calculations are available:

[0075] The electrochemical efficiency of the stack:

[0076] The hydrogen consumption rate of the stack:

[0077] where V is the average single-cell voltage of the stack (Volt); P is the output power of the stack (W).

[0078] Figure 3 Shows the relationship between the power of the fuel cell stack, the stack efficiency and the output current.

[0079] Furthermore, for the real-time hydrogen consumption of the stack: Select the time period from t1 to t2, integrate the hydrogen consumption rate with time, and obtain the hydrogen consumption of the stack within a specific time period:

[0080]

[0081] For the above formula in real time, when t1 is infinitely close to or equal to t2, it is the hydrogen consumption at the current moment, corresponding to the hydrogen consumption rate of the stack mentioned above.

[0082] The present invention takes into account that because hydrogen molecules are very small, it is very easy to diffuse and escape through the pores or gaps of materials, and there is currently no material that can absolutely prevent hydrogen from diffusing and escaping. The hydrogen escape amount of the hydrogen cylinder and the fuel cell system is related to the bottle pressure and time and needs to be verified through experiments. Generally, it is estimated by multiplying the maximum hydrogen escape rate determined in the specification of the hydrogen cylinder and the fuel cell system by the time since shutdown and the current operation time.

[0083] In addition, due to the diffusion of cathode gas, the concentration of nitrogen in the anode of the fuel cell will gradually increase, resulting in a decrease in hydrogen purity and a reduction in fuel cell efficiency. Therefore, it is necessary to indirectly flush the anode gas through the tail exhaust valve; the loss of hydrogen in the hydrogen cylinder due to flushing also needs to be calibrated. The parameters of the flushing valve are the period and duration, and the amount of hydrogen lost during each flushing is basically the same. During the calibration process, it can be carried out through the control records of the FCU.

[0084] Therefore, the real-time hydrogen consumption of the fuel cell system during operation is:

[0085]

[0086] Where C d is the maximum hydrogen escape rate (g / s) of the hydrogen cylinder and the system; τ is the last shutdown time before the system is started, and C f is the hydrogen loss amount (g / s) for a single flushing.

[0087] Furthermore, the real-time hydrogen state SoE of the vehicle is obtained H2 as:

[0088] SoE H2 = C p n – C e (8)

[0089] For the storage method of solid hydrogen storage materials, the hydrogen state SoE H2 also represents the real-time remaining hydrogen amount (g) during the operation of the fuel cell.

[0090] Based on the above analysis and calculation process, finally, the real-time hydrogen state SoE of the vehicle H2 is converted into the remaining driving mileage of the fuel cell vehicle.

[0091] For the calculation of the remaining mileage, it can also be calculated by the distance traveled from t1 to t2 and the hydrogen consumption to calculate the mileage that the remaining hydrogen can travel. By taking values of the time scale change formed from t1 to t2 to achieve calculations in different time periods and different environments (including external environment, road conditions, driving habits, etc.). For example, if the hydrogen consumption from t1 to t2 is for a highway section, the calculated remaining mileage is not very applicable to a low-speed bumpy section. However, the present invention can obtain a comprehensive calculation by taking a longer time period from t1 to t2 (for example, including road conditions such as low speed and high speed), and accordingly, it can also analyze the situation of the remaining section through GPS or navigation to adjust the calculated output value. For example, if t1 to t2 is for a highway section, but the navigation next is a low-speed section, then it can be processed by taking a longer time period. The present invention can also take a shorter time period to obtain the immediate hydrogen consumption situation.

[0092] It should be noted here that the present invention can also be applied to the applications of large vehicles, ships or aircraft.

[0093] Combined with Figure 4 , this embodiment provides a fuel cell-lithium battery hybrid system and related structures, including a lithium battery module, a fuel cell module, a hydrogen storage module, a fuel cell controller FCU, a vehicle controller VCU, and a motor. The solid-state hydrogen storage module includes a temperature sensor and a pressure sensor, and the fuel cell module includes voltage acquisition, a temperature sensor, and a cooling fan speed. The vehicle controller VCU coordinates and supports the power of the negative motor according to a preset energy management strategy. In the present invention, the VCU optimizes the output power of the fuel cell system and the lithium battery module according to the power demand of the motor and the energy power optimization combustion management strategy. The vehicle conditions can be preset and input through a graph, including the cycle and running time of the driving speed and slope, as well as the distance to be run. The VCU control strategy includes the SOC threshold for lithium battery charge and discharge, and the power vs efficiency curve of the fuel cell module.

Claims

1. A method for calculating the real-time hydrogen storage amount and remaining cruising range of a fuel cell vehicle, characterized in that, The method steps include: (1) Calibrate the hydrogen storage device and conduct charge-discharge cycle test analysis throughout its life cycle to obtain the initial hydrogen storage capacity C p 0 and the relationships between the hydrogen storage capacity in each cycle and the temperature, pressure, including the hydrogen state (2) Considering the hydrogen storage performance attenuation of the hydrogen storage device and the hydrogen storage material, a correction factor is introduced to estimate the actual hydrogen storage amount of the hydrogen storage device during this charge and discharge cycle. The calculation formula is: C p n = C p 0 e -hn where n represents the number of cycles, and C p n is the measured hydrogen storage capacity after the n-th cycle, and k is the decay constant, which is determined by PCT curve fitting or cyclic hydrogen absorption and desorption tests; (3) Based on the maximum hydrogen escape rate and the hydrogen loss caused by flushing during the operation of the hydrogen storage device and the fuel cell system, calculate the hydrogen consumption of the fuel cell stack during this cycle. The calculation method is as follows: Wherein, P(t) represents the function of the stack output power varying with time, ε(t) represents the electrochemical efficiency of the stack, t1 and t2 are the start and end times of the fuel cell working within this cycle, C d is the maximum hydrogen escape rate of the hydrogen cylinder and the system, τ is the sum of the most recent shutdown and operation times before the system is started, C f is the hydrogen loss amount for a single flushing; (4) Calculation of the real-time remaining hydrogen storage SoE during vehicle operation H2 Calculation: SoE H2 = C p n – C e (5) Based on the remaining hydrogen storage amount, calculate the remaining cruising range in real time. This calculation includes calculating based on the mileage traveled and the hydrogen consumption within the time period from t1 to t2.

2. The real-time hydrogen storage amount and remaining cruising range calculation method for a fuel cell vehicle according to claim 1, characterized in that, In step (1), the analysis steps of the influence of the hydrogen storage material on the hydrogen storage amount are as follows: 1) Place the hydrogen storage material in a vacuum container, maintain the hydrogen pressure at 2 - 6 MPa to form a metal hydride compound, then raise the temperature to 300 - 500 °C, and maintain a hydrogen soak for 1 - 10 hours on the high-temperature hydrogen platform to promote the formation of α and β crystal form metal hydrides, and complete the soaking treatment; 2) Perform an activation cycle treatment on the hydrogen storage material processed in step 1), including subjecting the hydrogen storage material to several pressure swing absorption - desorption cycles to promote and improve its reaction kinetics, and complete the pretreatment work of the hydrogen storage material by exposing the hydrogen storage material to hydrogen and reducing the pressure to release hydrogen; 3) Record the hydrogen storage amount of the activated hydrogen storage material at a constant temperature, record the change in hydrogen absorption amount at different pressures until saturation, and then calculate the hydrogen storage capacity at each pressure point through the mass difference; 4) Adjust the temperature and keep it constant for a period of time, while controlling the change in hydrogen pressure, measure the corresponding equilibrium hydrogen content in the material, and obtain the isothermal equilibrium line of the hydrogen storage material at different temperatures, including obtaining the relationship between hydrogen pressure and the composition of the hydrogen storage material represented graphically; 5) Based on the isothermal line of the hydrogen storage amount obtained in step 4) and the relationship between the equilibrium hydrogen pressure and the hydrogen storage amount, construct a PCT model of the hydrogen storage material for hydrogen storage amount, which is used to map the relationship between temperature and hydrogen equilibrium pressure within the working temperature range of the material, and obtain the relationship between the pressure of the hydrogen storage bottle and the hydrogen storage amount.

3. The method for calculating the real-time hydrogen storage amount and remaining cruising range of a fuel cell vehicle according to claim 1, characterized in that, The calculation of the initial hydrogen storage amount in step (2) is achieved based on the analysis of the relationship between the hydrogen storage amount, temperature, and pressure of the hydrogen storage material, including the pressure swing hydrogen storage amount and the isothermal equilibrium amount; The so-called pressure swing hydrogen storage amount refers to measuring the hydrogen storage amount of the activated hydrogen storage material at a constant temperature, and the so-called isothermal equilibrium amount refers to controlling the change in hydrogen pressure at different temperatures and measuring the corresponding equilibrium hydrogen content in the hydrogen storage material.

4. The method for calculating the real-time hydrogen storage amount and remaining cruising range of a fuel cell vehicle according to claim 1, characterized in that The estimation of the initial hydrogen storage amount includes obtaining a PCT curve based on the pressure - composition - temperature analysis of the hydrogen storage material. This PCT curve can characterize the relationship between hydrogen pressure and the hydrogen concentration in the material when the hydrogen storage material absorbs and releases hydrogen at different temperatures; This method constructs a PCT model of the hydrogen storage material and fits the model based on the Van't Hoff equation.

5. The method for calculating the real-time hydrogen storage amount and remaining cruising range of a fuel cell vehicle according to claim 1, wherein In the calculation of the hydrogen consumption of a fuel cell stack, when t1 is infinitely close to or equal to t2, the real-time hydrogen consumption rate of the stack is obtained as follows: In this method, the electrochemical efficiency of the stack In the formula, V represents the average single - cell voltage of the stack, and P is the output power of the stack.

6. The method for calculating the real-time hydrogen storage amount and remaining cruising range of a fuel cell vehicle according to claim 1, characterized in that, The method for calculating the remaining cruising range includes applying different road sections based on the time scale composed of t1 and t2 and its adjustment, and also includes calculating the real-time driving speed and driving distance of the vehicle through GPS real-time positioning information; calculating the hydrogen consumption per 100 kilometers during this time period according to the calculated real-time driving speed and driving distance and the power generation of the hydrogen system within a certain time period, and estimating the remaining cruising range.

7. The method for calculating the real-time hydrogen storage amount and remaining cruising range of a fuel cell vehicle according to claim 1, characterized in that, For the hydrogen escape amount of the hydrogen storage device, the method is to estimate it by multiplying the maximum hydrogen escape rate of the hydrogen storage material by the time since shutdown, and the maximum hydrogen escape rate is determined by experiments.

8. A real-time hydrogen storage amount and remaining driving range display system for a fuel cell vehicle, characterized in that, It includes: A solid-state hydrogen storage device for supplying hydrogen to the fuel cell stack; The fuel cell controller FCU obtains data including the pressure sensor and temperature sensor of the hydrogen storage device, records the number of cycles of the hydrogen storage device, and obtains the measured hydrogen storage capacity C after the nth cycle. p n Then, it performs the hydrogen storage amount calculation and remaining mileage calculation described in any one of claims 1-7.

9. The real-time hydrogen storage amount and remaining cruising range display system for a fuel cell vehicle according to claim 8, characterized in that, The fuel cell controller FCU includes obtaining the temperature of the fuel cell stack and real-time monitoring, collecting the voltage of each single cell of the stack, and is used to calculate the real-time hydrogen consumption rate of the stack.

10. The fuel cell real-time vehicle hydrogen storage amount and remaining cruising range display system according to claim 8 or 9, characterized in that, On the gas supply pipeline from the hydrogen storage device to the fuel cell stack, a pressure sensor and a pressure reducing valve are provided.

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