WO2024109162A1 - Cold start-up control method for fuel cell stack - Google Patents

Abstract

A cold start-up control method for a fuel cell stack. The cold start-up control method comprises: acquiring an initial temperature and an initial impedance of a fuel cell stack, querying a cold start-up control curve graph according to the initial temperature and the initial impedance to obtain a stoichiometric fuel ratio and a stoichiometric oxidant ratio, and introducing fuel and oxidant into the fuel cell stack on the basis of the stoichiometric fuel ratio and the stoichiometric oxidant ratio (S110); and controlling the current loading of the fuel cell stack, and if the temperature of the stack is greater than or equal to a preset temperature, the cold start-up of the fuel cell stack being successful (S120).

Description

Cold start control method for fuel cell stack

This application claims priority to the Chinese patent application filed with the China Patent Office on November 22, 2022, with application number 202211469496.8, the entire contents of which are incorporated by reference into this application.

Technical Field

The present application belongs to the field of fuel cell technology, for example, a cold start control method for a fuel cell stack.

Background technique

Fuel cell stack cold start control is an important part of fuel cell control strategy, and fuel cell stack cold start performance is a key indicator of fuel cell applicability in low temperature environment. The startup problem of proton exchange membrane fuel cells has not been completely solved, and there is no systematic explanation of the method and control strategy for low temperature unassisted self-starting of fuel cell stacks. There are no clear parameters for the conditions and control strategy of fuel cell stack self-starting. The reason is that: on the one hand, it is difficult to control the water balance of proton exchange membrane under low temperature conditions. When the water in the membrane is too low, the mass transfer efficiency is low. When there is too much water, it is easy to freeze and block the channel of fuel reaction; on the other hand, during the cold start process, the stack will experience local gas shortage and water blockage, and the stack has poor consistent performance, which affects the life and overall performance of the stack.

Cold start methods mostly adopt the form of auxiliary heating or the method of controlling an external circuit. CN103825037A discloses a fuel cell cold start rapid heating system, including a hydrogen delivery pipeline and a fuel cell stack. The hydrogen delivery pipeline delivers hydrogen to the flow channel on the anode side of the fuel cell stack. The system also includes a heater, a thermometer and a battery control system; the heater is arranged on the hydrogen delivery pipeline and is arranged to heat the hydrogen; the thermometer is arranged inside the fuel cell stack and is arranged to measure the temperature of the stack; the data acquisition end of the battery control system is connected to the thermometer, and the output end is connected to the heater, and the heater is turned on and off according to the temperature inside the stack measured by the thermometer. CN113707904A discloses a self-heating fuel cell vehicle cold start heater and a heating method. The heater includes a self-heating agent tank body, the inner cavity of the self-heating agent tank body is filled with self-heating agent powder, and the self-heating agent tank body is provided with an air inlet connected to an air compressor. The self-heating agent powder undergoes an oxidation-reduction reaction with the air entering through the air inlet to generate a large amount of heat, thereby realizing rapid heating of the components that need to be heated during the cold start process. The above patent uses auxiliary heating to achieve cold start, which requires the addition of components such as heaters, increasing the complexity and cost of the system.

Other methods without external auxiliary heating include: using multiple current density gradient loading forms or using intermittent cessation of oxidant supply or heating methods for hydrogen and oxygen on the same side reaction. CN114188570A discloses a cold start method, device and vehicle for a fuel cell stack, the method comprising: after completing shutdown purge, introducing hydrogen into the anode inlet of the stack based on a first preset parameter, and introducing oxygen into the cathode inlet of the stack. Gas. If it is detected that the minimum voltage and the average voltage of the battery in the stack meet the first preset condition, the first current is loaded to the stack step by step according to the preset current density gradient. If the detected minimum voltage and the average voltage meet the second preset condition, hydrogen is introduced into the anode inlet of the stack based on the second preset parameter, and oxygen is introduced into the cathode inlet of the stack, and the second current of the target current density value is loaded into the stack. If the detected minimum voltage and the average voltage meet the third preset condition, and the detected temperature of the coolant outlet of the stack is within the preset temperature range, the cold start of the stack is completed. However, the above-mentioned method of loading multiple current density gradients increases the repeatability of the control strategy and the start-up time is long. In addition, the method of heating the hydrogen and oxygen reactions on the same side is also prone to cause permanent damage to the fuel cell stack. At the same time, the above-mentioned cold start method cannot adaptively adjust the stoichiometric ratio of fuel and oxidant according to the actual cold start state, resulting in waste of fuel and oxidant, and reducing the efficiency of the fuel cell stack system.

In addition, the above method requires that the water content range in the fuel cell stack is small when the fuel cell stack is cold started at low temperature, which cannot meet the actual state of the fuel cell stack shutdown cold start, easily causing cold start failure and lack of protection for the fuel cell stack.

Summary of the invention

The present application provides a cold start control method for a fuel cell stack, which reduces redundant control programs, is easy to implement, and does not require external auxiliary heating, thereby simplifying the system structure and reducing system costs.

The present application provides a cold start control method for a fuel cell stack, the cold start control method comprising:

Obtaining an initial temperature and an initial impedance of a fuel cell stack, querying a cold start control curve diagram according to the initial temperature and the initial impedance, obtaining a fuel stoichiometric ratio and an oxidant stoichiometric ratio, and introducing fuel and an oxidant into the fuel cell stack based on the fuel stoichiometric ratio and the oxidant stoichiometric ratio;

The fuel cell stack loading current is controlled. If the stack temperature is greater than or equal to the preset temperature, the fuel cell stack cold start is successful.

In one or more embodiments, the cold start control method comprises the following steps:

Setting the average single-chip voltage protection value U ₀ , the minimum single-chip voltage protection value U ₁ and the first current density C ₀ of the fuel cell stack during cold start;

Obtaining the initial temperature T ₀ and initial impedance H ₀ of the fuel stack, querying the cold start control curve diagram according to the initial temperature T ₀ and initial impedance H ₀ , obtaining the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ , and introducing fuel and oxidant into the fuel stack based on the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ ;

Set the rate V ₀ of the stack loading current and load the current to obtain the loading current density;

Determine whether the acquired current density is greater than or equal to the first current density C ₀ , if the determination result is yes;

Setting a fuel stoichiometric ratio F ₁ and an oxidant stoichiometric ratio O ₁ , and introducing fuel and oxidant into the fuel stack based on the fuel stoichiometric ratio F ₁ and the oxidant stoichiometric ratio O ₁ ;

The stack is loaded with current to a second current density C ₁ ;

Get the stack temperature;

Determine whether the stack temperature is greater than or equal to the preset temperature. If the judgment result is yes, the stack cold start is successful.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a flow chart of a cold start control method for a fuel cell stack provided in an embodiment of the present application;

FIG2 is a flow chart of a cold start control method for a fuel cell stack provided in one embodiment of the present application;

FIG3 is a cold start control curve diagram of fuel provided in an embodiment of the present application;

FIG4 is a cold start control curve diagram of an oxidant provided in an embodiment of the present application;

FIG5 is a schematic structural diagram of a cold start control device for a fuel cell stack provided in an embodiment of the present application;

FIG6 is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

Detailed ways

The technical solution of the present application is explained below with reference to the accompanying drawings and through implementation methods.

The present application provides a cold start control method for a fuel cell stack, as shown in FIG1 , the cold start control method comprising:

S110, obtaining the initial temperature and initial impedance of the fuel cell stack, querying the cold start control curve chart according to the initial temperature and the initial impedance, obtaining the fuel metering ratio and the oxidant metering ratio, and introducing fuel and oxidant into the fuel cell stack based on the fuel metering ratio and the oxidant metering ratio.

S120, controlling the stack loading current; if the stack temperature is greater than or equal to a preset temperature, the stack cold start is successful.

The present application provides a cold start control method for a fuel cell stack, which reduces redundant control programs, shortens the loading time of the stack cold start, and does not require external auxiliary heating, thereby simplifying the structure of the system and reducing the cost of the system. In addition, the present application determines the optimal fuel metering ratio and the optimal oxidant metering ratio according to the cold start control curve, which can effectively improve the use efficiency of fuel and oxidant and the success rate of cold start, and widen the range of water content in the stack during cold start of the stack, thereby improving the applicability of the fuel cell stack in winter and cold areas.

The cold start control curve diagram (MAP diagram) of the present application is a relationship diagram between the temperature, high-frequency impedance and raw material stoichiometric ratio of the fuel cell stack. The cold start control curve diagram includes a relationship diagram between temperature, high-frequency impedance and fuel stoichiometric ratio, and a relationship diagram between temperature, high-frequency impedance and oxidant stoichiometric ratio.

The optimal fuel stoichiometric ratio and the optimal oxidant stoichiometric ratio determined according to the cold start control curve are the minimum fuel stoichiometric ratio and the minimum oxidant stoichiometric ratio required for the cold start of the fuel stack. Increasing the stoichiometric ratio of fuel and oxidant on this basis can improve the success rate of cold start. However, considering factors such as raw material costs, the increased stoichiometric ratio is limited.

In this application, a series of tests are designed to obtain a cold start control curve. For example, the method for obtaining the cold start control curve for the fuel stoichiometric ratio is as follows: keep the oxidant stoichiometric ratio and the cold start temperature constant, change the water content of the stack to change the initial impedance of the stack, and then collect the minimum fuel stoichiometric ratio required for a successful cold start of the stack under different initial impedances. After the data is aggregated, a curve at a certain temperature is obtained, and then the cold start temperature is changed for multiple tests to obtain a cold start control curve for the fuel stoichiometric ratio. The cold start control curve for the oxidant stoichiometric ratio can be obtained in the same way.

In one or more embodiments, as shown in FIG. 2 , the cold start control method includes the following steps.

Step 1: Set the average single-chip voltage protection value U ₀ , the minimum single-chip voltage protection value U ₁ and the first current density C ₀ of the fuel cell stack during cold start, and proceed to step 2. Here, step 1 is a preparatory action before cold start.

Step 2: Obtain the initial temperature T ₀ and initial impedance H ₀ of the fuel stack, query the cold start control curve diagram according to the initial temperature T ₀ and initial impedance H ₀ , obtain the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ , and introduce fuel and oxidant into the fuel stack based on the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ .

Step 3: Set the stack loading current rate V ₀ and load the current, obtain the loading current density, and proceed to step 4 for logical judgment.

Step 4: Determine whether the acquired current density is greater than or equal to the first current density C ₀ . If the determination result is yes, proceed to step 9 .

Step 9: Set the fuel stoichiometric ratio F ₁ and the oxidant stoichiometric ratio O ₁ , and introduce fuel and oxidant into the fuel stack based on the fuel stoichiometric ratio F ₁ and the oxidant stoichiometric ratio O ₁ , and proceed to step 10 .

Step 10: Load the stack with current to a second current density C ₁ , and proceed to step 11 .

Step 11: Get the temperature of the battery stack and go to step 12 for logical judgment.

Step 12: Determine whether the temperature of the battery stack is greater than or equal to the preset temperature. If the judgment result is yes, the battery stack cold start is successful.

In the present application, the initial impedance _H0 is the initial high-frequency impedance of the battery stack.

In one or more embodiments, in step 4: if the judgment result is no, proceed to step 5 for logical judgment.

Step 5: Determine whether the average single-chip voltage is greater than the average single-chip voltage protection value U ₀ and the minimum single-chip voltage is greater than the minimum single-chip voltage protection value U ₁ during the loading process. If the judgment result is yes, return to step 3; if the judgment result is no, proceed to step 6. The average single-chip voltage protection value U ₀ and the minimum single-chip voltage protection value U ₁ in step 5 are determined in real time during the loading process. That is, step 3 and step 5 can be executed at the same time.

Step 6: Run stably at the current density described in step 3, and record the stabilization time S ₁ , and proceed to step 7 for logic judgment.

Step 7: Determine whether the stabilization time _S1 is less than the protection time _S0 . If the determination result is yes, proceed to step 5 for logic determination. If the determination result is no, proceed to step 8.

Step 8: Set the fuel metering ratio increment ΔF and the oxidant metering ratio increment ΔO, and introduce fuel and oxidant into the fuel stack based on the increased fuel metering ratio and oxidant metering ratio, and proceed to step 5 for logical judgment.

In the present application, step 5 also includes the step of obtaining the average single-chip voltage and the minimum single-chip voltage of the battery stack; after obtaining the average single-chip voltage and the minimum single-chip voltage of the battery stack, logical judgment is performed.

The present application sets a voltage protection strategy, which increases the fuel metering ratio/oxidant metering ratio in step 8 to prevent cold start failure caused by too low single-chip voltage or low overall average voltage during cold start, improve the voltage consistency of the stack during cold start, protect the performance of the fuel cell stack, and increase its service life.

In the present application, steps 3 to 8 may be continuously cycled until the target current density C ₀ is loaded.

In one or more embodiments, in step 12: if the judgment result is no, proceed to step 13.

Step 13: Stable operation at the second current density _C1 for a preset time, and then proceed to step 11.

In one or more embodiments, the average single-chip voltage protection value U ₀ is 0.2-0.5V, for example, 0.2V, 0.25V, 0.3V, 0.35V, 0.4V, 0.45V or 0.5V.

In one or more embodiments, the minimum single-chip voltage protection value _U1 is -0.2 to 0.1V, for example, it can be -0.2V, -0.15V, -0.1V, -0.05V, 0V, 0.05V or 0.1V.

In one or more embodiments, the first current density C ₀ is 0.4-0.65 A/cm ² , for example, 0.4 A/cm ² , 0.42 A/cm ² , 0.45 A/cm ² , 0.47 ^A /cm ² , 0.5 A/cm 2 , 0.52 A/cm ² , 0.55 A/cm ² , 0.57 A/cm ² , 0.6 A/cm ² , 0.62 A/cm ² or 0.65 A/cm ² , etc.

In one or more embodiments, the initial temperature T ₀ is -30 to -5°C, for example, -30°C, -25°C, -20°C, -15°C, -10°C or -5°C.

In one or more embodiments, based on the fuel metering ratio F ₀ , the pressure of the introduced fuel is 70-100 kPag, for example, 70 kPag, 75 kPag, 80 kPag, 85 kPag, 90 kPag, 95 kPag or 100 kPag.

In one or more embodiments, based on the oxidant stoichiometric ratio O ₀ , the pressure of the introduced oxidant is 60-90 kPag, for example, 60 kPag, 65 kPag, 70 kPag, 75 kPag, 80 kPag, 85 kPag or 90 kPag.

In one or more embodiments, the rate _V0 of the loading current in step 3 is 10-20 A/s, for example, it can be 10 A/s, 11 A/s, 12 A/s, 13 A/s, 14 A/s, 15 A/s, 16 A/s, 17 A/s, 18 A/s, 19 A/s or 20 A/s, etc.

In one or more embodiments, the protection time _S0 is 5 to 30 seconds, for example, it may be 5 seconds, 7 seconds, 10 seconds, 12 seconds, 15 seconds, 17 seconds, 20 seconds, 22 seconds, 25 seconds, 27 seconds or 30 seconds.

In this application, the protection time is the minimum single-chip protection time.

In one or more embodiments, the fuel metering ratio increment ΔF is 0.1-0.3, for example, it may be 0.1, 0.12, 0.15, 0.17, 0.2, 0.22, 0.25, 0.27 or 0.3.

In one or more embodiments, the oxidant stoichiometric ratio increment ΔO is 0.2 to 0.5, for example, it may be 0.2, 0.22, 0.25, 0.27, 0.3, 0.32, 0.35, 0.37, 0.4, 0.42, 0.45, 0.47 or 0.5, etc.

In the present application, compared with the fuel stoichiometric ratio F ₀ , the increment of the fuel stoichiometric ratio F ₁ is 0.1-0.3 to increase the amount of fuel used; compared with the oxidant stoichiometric ratio O ₀ , the increment of the oxidant stoichiometric ratio O ₁ is 0.2-0.5 to increase the amount of oxidant used.

In one or more embodiments, the fuel metering ratio _F1 is 1.2 to 1.8, for example, it can be 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1. or 1.8, etc.

In one or more embodiments, the oxidant stoichiometric ratio _O1 is 2.0 to 2.5, for example, 2.0, 2.05, 2.1, 2.15, 2.2, 2.25, 2.3, 2.35, 2.4, 2.45 or 2.5, etc.

In one or more embodiments, based on the fuel metering ratio F ₁ , the pressure of the incoming fuel is 100-140 kPag, for example, 100 kPag, 105 kPag, 110 kPag, 115 kPag, 120 kPag, 125 kPag, 130 kPag, 135 kPag or 140 kPag.

In one or more embodiments, based on the oxidant stoichiometric ratio O ₁ , the pressure of the oxidant introduced is 80-120 kPag, for example, 80 kPag, 85 kPag, 90 kPag, 95 kPag, 100 kPag, 105 kPag, 110 kPag, 115 kPag or 120 kPag.

In one or more embodiments, the second current density _C1 is 0.6-0.8 A/ ^cm2 , for example, 0.6 A/ ^cm2 , 0.62 A/ ^cm2 , 0.65 A ^{/ cm2} , 0.67 A/cm2, 0.7 A/ ^cm2 , 0.72 A/ ^cm2 , 0.75 A/ ^cm2 , 0.78 A/ ^cm2 , 0.8 A/ ^cm2 , etc.

In one or more embodiments, the rate of loading current in step 10 is 10-20 A/s, which can be 10 A/s, 11 A/s, 12 A/s, 13 A/s, 14 A/s, 15 A/s, 16 A/s, 17 A/s, 18 A/s, 19 A/s or 20 A/s, etc.

In one or more embodiments, the preset temperature is 50-60°C, for example, it may be 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C or 60°C.

The numerical range described in this application includes not only the point values listed above, but also any point values between the above numerical ranges that are not listed. Other unlisted numerical values within the numerical range are also applicable. Due to limited space and for the sake of brevity, this application no longer exhaustively lists the point values included in the range.

The present application provides a cold start control method for a fuel cell stack, which reduces redundant control programs, shortens the loading time of the stack cold start, and does not require external auxiliary heating, thereby simplifying the structure of the system and reducing the cost of the system. In addition, the present application determines the optimal fuel metering ratio and the optimal oxidant metering ratio according to the cold start control curve, which can effectively improve the use efficiency of fuel and oxidant and the success rate of cold start, and widen the range of water content in the stack during cold start of the stack, thereby improving the applicability of the fuel cell stack in winter and cold areas.

In one embodiment, the present application provides a cold start control method for a fuel cell stack, and the cold start control method includes the following steps (as shown in FIG. 2 ).

Step 1: Set the average single-chip voltage protection value U ₀ (0.2-0.5V), the minimum single-chip voltage protection value U ₁ (-0.2-0.1V) and the first current density C ₀ (0.4-0.65A/cm ² ) of the fuel cell stack during cold start, and then proceed to step 2.

Step 2: Obtain the initial temperature T ₀ (-30 to -5°C) and initial impedance H ₀ of the fuel stack, query the cold start control curve diagram (MAP diagram) according to the initial temperature T ₀ and the initial impedance H ₀ , obtain the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ , and based on the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ , introduce fuel (pressure of 70 to 100 kPag) and oxidant (pressure of 60 to 90 kPag) into the fuel stack.

Step 3: Set the rate V ₀ (10-20 A/s) of the stack loading current and load the current, obtain the loading current density, and proceed to step 4 for logical judgment.

Step 4: Determine whether the acquired current density is greater than or equal to the first current density C ₀ . If the determination result is yes, proceed to step 9 . If the determination result is no, proceed to step 5 for logic determination.

Step 5: Obtain the average single-chip voltage and the minimum single-chip voltage of the battery stack, and determine whether the average single-chip voltage is greater than the average single-chip voltage protection value U ₀ and the minimum single-chip voltage is greater than the minimum single-chip voltage protection value U ₁ during the loading process. If the judgment result is yes, return to step 3; if the judgment result is no, proceed to step 6.

Step 6: Run stably at the current density described in step 3, and record the stabilization time S ₁ , then proceed to step 7 Make logical judgments.

Step 7: Determine whether the stabilization time _S1 is less than the protection time _S0 (5-30s). If the determination result is yes, proceed to step 5 for logic determination. If the determination result is no, proceed to step 8.

Step 8: Set the fuel metering ratio increment ΔF (0.1~0.3) and the oxidant metering ratio increment ΔO (0.2~0.5), and based on the increased fuel metering ratio and oxidant metering ratio, introduce fuel and oxidant into the fuel stack, and proceed to step 5 for logical judgment.

Step 9: Set the fuel stoichiometric ratio F ₁ (1.2-1.8) and the oxidant stoichiometric ratio O ₁ (2.0-2.5), and introduce fuel and oxidant into the fuel stack based on the fuel stoichiometric ratio F ₁ and the oxidant stoichiometric ratio O ₁ , and proceed to step 10.

Step 10: Load the stack with current to a second current density C ₁ (0.6-0.8 A/cm ² ) at a rate of 10-20 A/s, and proceed to step 11 .

Step 11: Get the temperature of the battery stack and go to step 12 for logical judgment.

Step 12: Determine whether the stack temperature is greater than or equal to the preset temperature (50-60°C). If the judgment result is yes, the stack cold start is successful; if the judgment result is no, proceed to step 13.

Step 13: Stable operation at the second current density _C1 for a preset time, and then proceed to step 11.

Example 1

This embodiment provides a cold start control method for a fuel cell stack, comprising the following steps.

Step 1: Set the average single-chip voltage protection value U ₀ (0.4V), the minimum single-chip voltage protection value U ₁ (0.2V) and the first current density C ₀ (0.6A/cm ² ) of the fuel cell stack during cold start, and proceed to step 2.

Step 2: Obtain the initial temperature T ₀ (-20°C) and initial impedance H ₀ of the fuel stack, query Figure 3 according to the initial temperature T ₀ and initial impedance H ₀ to obtain the fuel stoichiometric ratio F ₀ , query Figure 4 to obtain the oxidant stoichiometric ratio O ₀ , and introduce fuel (pressure is 90 kPag) and oxidant (pressure is 70 kPag) into the fuel stack based on the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ .

Step 3: Set the stack loading current rate V ₀ (20A/s) and load the current, obtain the loading current density, and proceed to step 4 for logical judgment.

Step 4: Determine whether the acquired current density is greater than or equal to the first current density C ₀ . If the determination result is yes, proceed to step 9 .

Step 9: Set the fuel stoichiometric ratio F ₁ (1.5) and the oxidant stoichiometric ratio O ₁ (2.1), and introduce fuel and oxidant into the fuel stack based on the fuel stoichiometric ratio F ₁ and the oxidant stoichiometric ratio O ₁ , and proceed to step 10.

Step 10: Load the stack with current to a second current density C ₁ (0.8 A/cm ² ) at a rate of 20 A/s, and proceed to step 11 .

Step 11: Get the temperature of the battery stack and go to step 12 for logical judgment.

Step 12: Determine whether the stack temperature is greater than or equal to the preset temperature (50°C). If the judgment result is yes, the stack cold start is successful; if the judgment result is no, go to step 13; if the initial judgment result is no, go to step 13.

Step 13: Run stably at the second current density _C1 for a preset time (60s), enter step 11, obtain the temperature of the battery stack and judge it in step 12. If the judgment result is yes, the battery stack cold start is successful.

Example 2

This embodiment provides a cold start control method for a fuel cell stack, comprising the following steps.

Step 1: Set the average single-chip voltage protection value U ₀ (0.2V), the minimum single-chip voltage protection value U ₁ (-0.1V) and the first current density C ₀ (0.5A/cm ² ) of the fuel cell stack during cold start, and then proceed to step 2.

Step 2: Obtain the initial temperature T ₀ (-30°C) and initial impedance H ₀ of the fuel stack, query Figure 3 according to the initial temperature T ₀ and initial impedance H ₀ to obtain the fuel stoichiometric ratio F ₀ , query Figure 4 to obtain the oxidant stoichiometric ratio O ₀ , and introduce fuel (pressure of 100 kPag) and oxidant (pressure of 80 kPag) into the fuel stack based on the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ .

Step 3: Set the stack loading current rate V ₀ (10A/s) and load the current, obtain the loading current density, and proceed to step 4 for logical judgment.

Step 4: Determine whether the acquired current density is greater than or equal to the first current density C ₀ . If the determination result is yes, proceed to step 9 . If the determination result is no, proceed to step 5 for logic determination. If the initial determination result is no, proceed to step 5 .

Step 5: Obtain the average single-chip voltage and the minimum single-chip voltage of the battery stack, and determine whether the average single-chip voltage is greater than the average single-chip voltage protection value U ₀ and the minimum single-chip voltage is greater than the minimum single-chip voltage protection value U ₁ during the loading process. If the judgment result is yes, return to step 3; if the judgment result is no, proceed to step 6.

Step 6: Run stably at the current density in step 3, record the stabilization time S ₁ , and proceed to step 7 for logic judgment.

Step 7: Determine whether the stabilization time _S1 is less than the protection time _S0 (15s). If the determination result is yes, proceed to step 5 for logic determination. If the determination result is no, proceed to step 8.

Step 8: Set the fuel metering ratio increment ΔF (0.2) and the oxidant metering ratio increment ΔO (0.3), and based on the increased fuel metering ratio and oxidant metering ratio, introduce fuel and oxidant into the fuel stack, and proceed to step 5 for logical judgment.

Step 9: Set the fuel stoichiometric ratio F ₁ (1.6) and the oxidant stoichiometric ratio O ₁ (2.2), and introduce fuel and oxidant into the fuel stack based on the fuel stoichiometric ratio F ₁ and the oxidant stoichiometric ratio O ₁ , and proceed to step 10.

Step 10: Load the stack with current to a second current density C ₁ (0.7 A/cm ² ) at a rate of 10 A/s, and proceed to step 11 .

Step 11: Get the temperature of the battery stack and go to step 12 for logical judgment.

Step 12: Determine whether the stack temperature is greater than or equal to the preset temperature (50°C). If the judgment result is yes, the stack cold start is successful; if the judgment result is no, go to step 13; if the initial judgment result is no, go to step 13.

Step 13: Run stably at the second current density _C1 for a preset time (80s), enter step 11, obtain the temperature and then judge in step 12. If the judgment result is yes, the stack cold start is successful.

FIG5 is a schematic diagram of the structure of a cold start control device for a fuel cell stack provided in an embodiment of the present application. This embodiment can be applied to the case of cold start control of a fuel cell stack. The device can be implemented by software and/or hardware and can be integrated into electronic devices such as terminals.

As shown in FIG5 , the device may include the following modules.

The fuel and oxidant control module 210 is configured to obtain an initial temperature and an initial impedance of the stack, query a cold start control curve chart according to the initial temperature and the initial impedance, obtain a fuel metering ratio and an oxidant metering ratio, and introduce fuel and oxidant into the stack based on the fuel metering ratio and the oxidant metering ratio;

The starting module 220 is configured to control the stack loading current. If the stack temperature is greater than or equal to a preset temperature, the stack cold start is successful.

The apparatus is configured to perform the following steps:

Step 1: Set the average single-chip voltage protection value U ₀ , the minimum single-chip voltage protection value U ₁ and the first current density C ₀ of the fuel cell stack during cold start, and proceed to step 2;

Step 2: Obtain the initial temperature T ₀ and initial impedance H ₀ of the fuel stack, query the cold start control curve diagram according to the initial temperature T ₀ and initial impedance H ₀ , obtain the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ , and introduce fuel and oxidant into the fuel stack based on the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ ;

Step 3: Set the rate V ₀ of the stack loading current and load the current, obtain the loading current density, and proceed to step 4 for logical judgment;

Step 4: Determine whether the acquired current density is greater than or equal to the first current density C ₀ . If the determination result is yes, proceed to step 9 .

Step 9: setting the fuel stoichiometric ratio F ₁ and the oxidant stoichiometric ratio O ₁ , and introducing the fuel and the oxidant into the fuel stack based on the fuel stoichiometric ratio F ₁ and the oxidant stoichiometric ratio O ₁ , and proceeding to step 10;

Step 10: Load the stack with current to a second current density C ₁ , and proceed to step 11;

Step 11: Get the temperature of the battery stack and proceed to step 12 for logical judgment;

Step 12: Determine whether the temperature of the battery stack is greater than or equal to the preset temperature. If the judgment result is yes, the battery stack cold start is successful.

In one or more embodiments, in step 4: if the judgment result is no, proceed to step 5 for logical judgment;

Step 5: Determine whether the average single chip voltage is greater than the average single chip voltage protection value U ₀ and the minimum single chip voltage is greater than the minimum single chip voltage protection value U ₁ during the loading process. If the determination result is yes, return to step 3. If the determination result is no, proceed to step 6.

Step 6: operate stably at the current density described in step 3, and record the stabilization time S ₁ , and proceed to step 7 for logic judgment;

Step 7: Determine whether the stabilization time _S1 is less than the protection time _S0 . If the determination result is yes, proceed to step 5 for logic determination. If the determination result is no, proceed to step 8.

Step 8: Set the fuel metering ratio increment ΔF and the oxidant metering ratio increment ΔO, and introduce fuel and oxidant into the fuel stack based on the increased fuel metering ratio and oxidant metering ratio, and proceed to step 5 for logical judgment.

In one or more embodiments, in step 12: if the judgment result is no, proceed to step 13;

Step 13: Stable operation at the second current density _C1 for a preset time, and then proceed to step 11.

In one or more embodiments, the average single chip voltage protection value U ₀ is 0.2 to 0.5 V;

In one or more embodiments, the minimum single chip voltage protection value _U1 is -0.2 to 0.1V;

In one or more embodiments, the first current density C ₀ is 0.4-0.65 A/cm ² ;

In one or more embodiments, the initial temperature T ₀ is -30 to -5°C.

In one or more embodiments, based on the fuel metering ratio F ₀ , the pressure of the incoming fuel is 70-100 kPag;

In one or more embodiments, based on the oxidant stoichiometric ratio O ₀ , the pressure of the introduced oxidant is 60-90 kPag.

In one or more embodiments, the rate V ₀ of the loading current in step 3 is 10-20 A/s;

In one or more embodiments, the protection time S ₀ is 5 to 30 s;

In one or more embodiments, the fuel metering ratio increment ΔF is 0.1 to 0.3;

In one or more embodiments, the oxidant stoichiometric ratio increment ΔO is 0.2 to 0.5.

In one or more embodiments, the fuel metering ratio _F1 is 1.2 to 1.8;

In one or more embodiments, the oxidant stoichiometric ratio O ₁ is 2.0 to 2.5;

In one or more embodiments, based on the fuel stoichiometric ratio F ₁ , the pressure of the incoming fuel is 100-140 kPag;

In one or more embodiments, based on the oxidant stoichiometric ratio O ₁ , the pressure of the introduced oxidant is 80-120 kPag.

In one or more embodiments, the second current density C ₁ is 0.6-0.8 A/cm ² ;

In one or more embodiments, the rate of loading current in step 10 is 10-20 A/s.

In one or more embodiments, the preset temperature is 50-60°C.

The cold start control device for a fuel cell stack provided in this embodiment can execute the cold start control method for a fuel cell stack provided in any embodiment of the present disclosure, and has the corresponding functional modules and effects for executing the cold start control method for a fuel cell stack. For technical details not fully described in this embodiment, please refer to the cold start control method for a fuel cell stack provided in any embodiment of the present disclosure.

FIG6 is a schematic diagram of the structure of an electronic device provided by an embodiment of the present application, and FIG6 shows a schematic diagram of the structure of an electronic device 410 that can be used to implement the embodiment. The electronic device 410 includes at least one processor 411, and a memory connected to the at least one processor 411 in communication, such as a read-only memory (ROM) 412, a random access memory (RAM) 413, etc., wherein the memory stores a computer program that can be executed by at least one processor 411, and the processor 411 can perform a variety of appropriate actions and processes according to the computer program stored in the ROM 412 or the computer program loaded from the storage unit 418 to the RAM 413. In the RAM 413, a variety of programs and data required for the operation of the electronic device 410 can also be stored. The processor 411, the ROM 412, and the RAM 413 are connected to each other through the bus 414. The input/output (I/O) interface 415 is also connected to the bus 414.

A number of components in the electronic device 410 are connected to the I/O interface 415, including: an input unit 416, such as a keyboard, a mouse, etc.; an output unit 417, such as various types of displays, speakers, etc.; a storage unit 418, such as a disk, an optical disk, etc.; and a communication unit 419, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 419 allows the electronic device 410 to exchange information/data with other devices through a computer network such as the Internet and/or various telecommunication networks.

Processor 411 may be a variety of general and/or special processing components with processing and computing capabilities. Some examples of processor 411 include a central processing unit (CPU), a graphics processing unit (GPU), a variety of special artificial intelligence (AI) computing chips, a variety of processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. Processor 411 performs the multiple methods and processes described above, such as the fuel cell stack. Cold start control method.

In some embodiments, the cold start control method of the fuel cell stack may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 418. In some embodiments, part or all of the computer program may be loaded and/or installed on the electronic device 410 via the ROM 412 and/or the communication unit 419. When the computer program is loaded into the RAM 413 and executed by the processor 411, one or more steps of the cold start control method of the fuel cell stack described above may be performed. Alternatively, in other embodiments, the processor 411 may be configured to perform the cold start control method of the fuel cell stack by any other appropriate means (e.g., by means of firmware).

Various embodiments of the systems and techniques described above herein may be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard parts (ASSPs), system on chip systems (SOCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and/or combinations thereof. These various embodiments may include: being implemented in one or more computer programs that are executable and/or interpreted on a programmable system including at least one programmable processor that may be a special purpose or general purpose programmable processor that may receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

The computer programs for implementing the methods of the present application may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer programs are executed by the processor, the functions/operations specified in the flow charts and/or block diagrams are implemented. The computer programs may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

In the context of the present application, a computer readable storage medium may be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer readable storage medium may include an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. Alternatively, a computer readable storage medium may be a machine readable signal medium. A machine readable storage medium includes an electrical connection based on one or more lines, a portable computer disk, a hard disk, RAM, ROM, an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. Storage The medium may be a non-transitory storage medium.

To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a cathode ray tube (CRT) or a liquid crystal display (LCD) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data processing server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: Local Area Network (LAN), Wide Area Network (WAN), blockchain network, and the Internet.

A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the respective computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and virtual private servers (VPS) services.

The various forms of processes shown above can be used to reorder, add or delete steps. For example, the multiple steps recorded in this application can be executed in parallel, sequentially or in different orders, as long as the expected results of the technical solution of this application can be achieved, and this document is not limited here.

The above description is only an implementation mode of the present application, but the protection scope of the present application is not limited thereto. Those skilled in the art should understand that any conceivable changes or substitutions within the technical scope disclosed in the present application are within the protection scope and disclosure scope of the present application.

Claims (15)

A cold start control method for a fuel cell stack, comprising: Obtaining an initial temperature and an initial impedance of a fuel cell stack, querying a cold start control curve diagram according to the initial temperature and the initial impedance, obtaining a fuel stoichiometric ratio and an oxidant stoichiometric ratio, and introducing fuel and an oxidant into the fuel cell stack based on the fuel stoichiometric ratio and the oxidant stoichiometric ratio; The fuel cell stack loading current is controlled, and when the stack temperature is greater than or equal to a preset temperature, the fuel cell stack cold start is successful. The method according to claim 1, wherein The method further includes: setting an average single-chip voltage protection value U ₀ , a minimum single-chip voltage protection value U ₁ and a first current density C ₀ of the fuel cell stack during cold start; Wherein, the obtaining of the initial temperature and initial impedance of the fuel cell stack, querying the cold start control curve diagram according to the initial temperature and the initial impedance, obtaining the fuel stoichiometric ratio and the oxidant stoichiometric ratio, and introducing the fuel and the oxidant into the fuel cell stack based on the fuel stoichiometric ratio and the oxidant stoichiometric ratio, comprises: obtaining the initial temperature T ₀ and the initial impedance H ₀ of the fuel cell stack, querying the cold start control curve diagram according to the initial temperature T ₀ and the initial impedance H ₀ , obtaining the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ , and introducing the fuel and the oxidant into the fuel cell stack based on the fuel stoichiometric ratio F ₀ and the oxidant stoichiometric ratio O ₀ ; Wherein, the controlling of the fuel cell stack loading current, when the stack temperature is greater than or equal to a preset temperature, the fuel cell stack cold start is successful, comprises: Setting a rate V ₀ at which the fuel cell stack is loaded with current and loading current, and obtaining a third current density of the loading; Determining whether the acquired third current density is greater than or equal to the first current density C ₀ , and if the first determination result is yes, setting a fuel stoichiometric ratio F ₁ and an oxidant stoichiometric ratio O ₁ , and introducing the fuel and the oxidant into the fuel cell stack based on the fuel stoichiometric ratio F ₁ and the oxidant stoichiometric ratio O ₁ ; Controlling the fuel cell stack to load current so that the current is loaded to a second current density C ₁ ; Acquiring the temperature of the battery stack; It is determined whether the temperature of the fuel cell stack is greater than or equal to the preset temperature. If the second determination result is yes, the cold start of the fuel cell stack is successful. The method according to claim 2, further comprising: if the first judgment result is no, judging whether the average single chip voltage is greater than the average single chip voltage protection value U ₀ and the lowest single chip voltage is greater than the lowest single chip voltage protection value U ₁ during the loading process; If the third judgment result is yes, the speed of setting the fuel cell stack loading current is executed. rate V ₀ and load current, and obtain the loaded third current density, and when the third judgment result is no, operate stably with the obtained third current density, and record the stabilization time S ₁ ; It is judged whether the stabilization time _S1 is less than the protection time _S0 . When the fourth judgment result is yes, it is judged whether the average single-chip voltage is greater than the average single-chip voltage protection value _U0 and the minimum single-chip voltage is greater than the minimum single-chip voltage protection value _U1 during the loading process. When the fourth judgment result is no, the fuel metering ratio increment ΔF and the oxidant metering ratio increment ΔO are set, and the fuel and the oxidant are introduced into the fuel cell stack based on the increased fuel metering ratio and the oxidant metering ratio, and it is judged whether the average single-chip voltage is greater than the average single-chip voltage protection value _U0 and the minimum single-chip voltage is greater than the minimum single-chip voltage protection value _U1 during the loading process. According to the method according to any one of claims 2 to 3, after judging whether the stack temperature is greater than or equal to the preset temperature, it also includes: when the second judgment result is no, stably running at a second current density _C1 for a preset time, and obtaining the stack temperature, judging whether the stack temperature is greater than or equal to the preset temperature, and when the second judgment result is yes, the fuel cell stack is cold started successfully. The method according to any one of claims 2 to 4, wherein the average single-chip voltage protection value _U0 is 0.2V to 0.5V. The method according to claim 5, wherein the method comprises at least one of the following: The minimum single-chip voltage protection value _U1 is -0.2V to 0.1V; The first current density C ₀ is 0.4A/cm ² to 0.65A/cm ² ; The initial temperature T ₀ is -30°C to -5°C. The method according to any one of claims 2 to 6, wherein the pressure of the fuel introduced is 70 kPag to 100 kPag based on the fuel stoichiometric ratio F ₀ . The method according to claim 7, wherein, based on the oxidant stoichiometric ratio O ₀ , the pressure of the oxidant introduced is 60 kPag to 90 kPag. The method according to claim 3, wherein the rate _V0 of the loading current is 10A/s to 20A/s. The method according to claim 9, wherein the method comprises at least one of the following: The protection time _S0 is 5s to 30s; The fuel metering ratio increment ΔF is 0.1 to 0.3; The oxidant stoichiometric ratio increment ΔO is 0.2 to 0.5. The method according to any one of claims 2 to 10, wherein the fuel metering ratio F ₁ It is 1.2 to 1.8. The method according to claim 11, wherein the method comprises at least one of the following: The oxidant stoichiometric ratio O ₁ is 2.0 to 2.5; Based on the fuel metering ratio F ₁ , the pressure of the fuel introduced is 100 kPag to 140 kPag; Based on the oxidant stoichiometric ratio O ₁ , the pressure of the oxidant introduced is 80 kPag to 120 kPag. The method according to any one of claims 2 to 12, wherein the second current density _C1 is 0.6 A/ ^cm2 to 0.8 A/ ^cm2 . The method according to claim 13, wherein In controlling the fuel cell stack to load current, the current is loaded to a second current density _C1 , and the rate of the current loading is 10A/s to 20A/s. The method according to any one of claims 1 to 14, wherein the preset temperature is 50°C to 60°C.