Evaluation method, system and equipment for consistency of galvanic pile monomers and storage medium

Abstract

The invention relates to a method, a system and equipment for evaluating the consistency of galvanic pile monomers, and a storage medium, and relates to the technical field of battery testing. The method comprises the following steps: when a galvanic pile is in a power supply state and the galvanic pile is interfered by disturbance current, obtaining the total voltage of the galvanic pile and the single voltage of each single battery in the galvanic pile; and according to the total voltage and the monomer voltage, evaluating the monomer consistency of the galvanic pile. Therefore, the overall voltage of the galvanic pile in the process that the galvanic pile is disturbed by the external current and the real-time data of the single voltage of each single battery in the galvanic pile are obtained, and the single consistency of the galvanic pile is evaluated according to the real-time data of the overall voltage and the single voltage, so that the single consistency of the galvanic pile is evaluated.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, in particular to the field of battery testing technology, and specifically to a method, system, device and storage medium for evaluating the consistency of battery stack cells. Background Art

[0002] Fuel cells are used as on-board power devices for electric vehicles. In actual use, since the output power of a fuel cell is limited, multiple fuel cells are often connected in series to form a fuel cell stack (fuel cell stack) to increase the output power of the fuel cell stack.

[0003] Since the performance of each single cell in the battery stack is different, there are also differences in the voltage between each single cell. If the difference between the voltages is large, the external power output capacity of the battery stack will be greatly reduced and the battery aging will be accelerated.

[0004] Therefore, how to evaluate the cell consistency of the fuel cell stack is an urgent problem that needs to be solved. Summary of the invention

[0005] The present application provides a method, system, device and storage medium for evaluating the consistency of a battery stack cell, so as to at least solve the technical problem that it takes a long time to evaluate the consistency of a battery stack cell in the related art. The technical solution of the present application is as follows:

[0006] According to the first aspect of the present application, a method for evaluating the consistency of battery stack cells is provided, comprising: when the battery stack is in a power supply state and the battery stack is disturbed by a disturbance current, obtaining the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack; the battery stack is a fuel cell stack; and based on the overall voltage and the single cell voltage, evaluating the single cell consistency of the battery stack.

[0007] According to the above technical means, the present application can evaluate the cell consistency of the stack by obtaining the real-time data of the overall voltage of the stack and the cell voltage of each single cell in the stack during the process of the stack being disturbed by external current, and according to the real-time data of the overall voltage and the cell voltage. Thus, by applying a disturbance current to the stack to make the current of the stack change rapidly, the overall voltage of the stack and the cell voltage of each single cell in the stack during the process of the stack being disturbed by external current are obtained, which will change with the current in the stack, and the cell consistency of the stack is evaluated according to the changes in the overall voltage of the stack and the cell voltage of each single cell in the stack, thereby achieving the evaluation of the cell consistency of the stack.

[0008] In one possible implementation, the cell consistency of the battery stack is evaluated based on the overall voltage and the cell voltage, including: calculating the average cell voltage of multiple single cells in the battery stack based on the overall voltage; determining the voltage difference corresponding to each single cell based on the average cell voltage and the cell voltage of each single cell; and determining that the cell consistency evaluation result of the battery stack is qualified when the voltage difference corresponding to each single cell is less than a difference threshold.

[0009] According to the above technical means, the average value of the overall voltage of the battery stack can reflect the concentration trend of the overall voltage of the battery stack. The present application can more accurately evaluate the consistency between single cells by calculating the average single cell voltage and comparing the voltage difference between the single cell voltage and the average single cell voltage. At the same time, comparing the voltage difference between the single cell voltage and the average single cell voltage does not require a complex data processing process, and can obtain the evaluation result more quickly, thereby improving the evaluation efficiency.

[0010] In a possible implementation, for any first single cell in the battery stack; according to the average single cell voltage and the single cell voltage of each single cell, determine the voltage difference corresponding to each single cell, including: calculating multiple reference voltage difference values ​​corresponding to the first single cell at multiple moments; the reference voltage difference value is the absolute value of the difference between the first voltage at the corresponding moment and the second voltage at the corresponding moment; the first voltage is the single cell voltage of the first single cell; the second voltage is the average single cell voltage of multiple single cells; the maximum value among the reference voltage difference values ​​corresponding to each of the multiple moments is determined as the voltage difference corresponding to the first single cell.

[0011] According to the above technical means, the present application uses the maximum value of the voltage difference within a period of time as the voltage difference corresponding to each single cell, so that the obtained voltage difference can more accurately characterize the performance of the battery, and further make the single cell consistency evaluation result of the battery stack more accurate.

[0012] In a possible implementation, before obtaining the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack when the battery stack is in a powered state and the battery stack is disturbed by a disturbance current, the method also includes: when the battery stack is in a powered state, determining whether the battery stack is in a stable powered state according to the overall voltage of the battery stack; when the battery stack is in a powered state and the battery stack is disturbed by a disturbance current, obtaining the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack, including: when the battery stack is in a stable powered state and the battery stack is disturbed by a disturbance current, obtaining the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack.

[0013] According to the above technical means, the present application can determine whether the battery stack is in a stable power supply state, and obtain the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack when it is in a stable power supply state, thereby improving the accuracy of the overall voltage and single cell voltage results.

[0014] In a possible implementation, determining whether the battery stack is in a stable power supply state based on the overall voltage of the battery stack includes: calculating the overall average voltage of the battery stack corresponding to each of multiple time periods based on the overall voltage of the battery stack; determining whether the battery stack is in a stable power supply state based on the overall average voltage of the battery stack corresponding to each of the multiple time periods.

[0015] According to the above-mentioned technical means, when the battery stack is in a stable power supply state, the voltage output by the battery stack is stable. The present application determines whether the voltage output by the battery stack is stable by calculating the overall average voltage in multiple time periods and comparing the difference in the overall average voltage in multiple time periods, and then determines whether the battery stack is in a stable power supply state. This method is simple and convenient, and it can clearly see whether the battery stack is in a stable power supply state.

[0016] In a possible implementation, determining whether the battery stack is in a stable power supply state is based on the overall average voltages corresponding to the battery stack in multiple time periods, including: determining the fluctuation amplitudes of multiple overall average voltages based on the overall average voltages corresponding to the battery stack in multiple time periods; the fluctuation amplitude is the difference between the maximum value and the minimum value of the multiple overall average voltages; and determining that the battery stack is in a stable power supply state when the fluctuation amplitudes of the multiple overall average voltages are less than a fluctuation amplitude threshold.

[0017] According to the above-mentioned technical means, since the voltage output by the battery stack is stable when the battery stack is in a stable power supply state, but the output voltage is not a fixed value, but fluctuates within a certain range, the present application can determine the fluctuation amplitude in multiple time periods. If the fluctuation amplitude is less than the fluctuation amplitude threshold, it is determined that the voltage output by the battery stack is stable, and then it is determined that the battery stack is in a stable power supply state. This method is not only simple and convenient, but also accurate.

[0018] In one possible embodiment, the stack is a hydrogen fuel cell stack; the hydrogen fuel cell stack is also connected to an air supply device, a hydrogen supply device, and a cooling device; when the fluctuation amplitude of multiple overall average voltages is less than the fluctuation amplitude threshold, the stack is determined to be in a stable power supply state, including: when the fluctuation amplitude of multiple overall average voltages is less than the fluctuation amplitude threshold, if the air supply device, the hydrogen supply device, and the cooling device meet the following conditions, the stack is determined to be in a stable power supply state: the fluctuation of the air intake flow rate is less than the first flow fluctuation threshold; the fluctuation of the air intake pressure is less than the first pressure fluctuation threshold; the fluctuation of the air intake temperature is less than the first temperature fluctuation threshold; the fluctuation of the hydrogen intake flow rate is less than the second flow fluctuation threshold; the fluctuation of the hydrogen intake pressure is less than the second pressure fluctuation threshold; the fluctuation of the hydrogen intake temperature is less than the second temperature fluctuation threshold; the fluctuation of the coolant inlet flow rate is less than the third flow fluctuation threshold; the fluctuation of the coolant inlet pressure is less than the third pressure fluctuation threshold; the fluctuation of the coolant inlet temperature is less than the third temperature fluctuation threshold.

[0019] According to the above-mentioned technical means, in the case that the battery stack is a hydrogen fuel cell battery stack, when the battery stack is powered, an air supply device, a hydrogen supply device, and a cooling device are required to provide external conditions for the battery stack, so the battery stack is in a stable power supply state which also includes the stability of various data of the air supply device, the hydrogen supply device, and the cooling device. The present application can determine whether the battery stack is in a stable power supply state by judging whether various data of the air supply device, the hydrogen supply device, and the cooling device are stable, so that the result that the battery stack is in a stable power supply state is more accurate and comprehensive.

[0020] In a possible implementation manner, the disturbance current is a constant frequency current or a variable frequency current.

[0021] According to the above-mentioned technical means, when the disturbance current is a variable frequency current, applying the variable frequency current within a period of time is equivalent to repeatedly applying the disturbance current. When the disturbance current is a fixed frequency current, by setting the time interval for applying the disturbance current, it is also possible to achieve multiple changes in current within a period of time, which is equivalent to repeatedly applying the disturbance current. The present application simulates multiple applications of the disturbance current by applying a fixed frequency current or a variable frequency current, which is equivalent to multiple evaluations of the cell consistency of the battery stack, thereby improving the accuracy of the cell consistency evaluation results.

[0022] According to a second aspect provided by the present application, a system for evaluating the consistency of battery stack cells is provided, comprising: a first load, a battery stack, a second load and an evaluation device; wherein the first load is respectively connected to the positive and negative electrodes of the battery stack; the second load is respectively connected to the positive and negative electrodes of the battery stack, and the second load is respectively connected to the positive and negative electrodes of each single cell in the battery stack; the second load is used to apply a disturbance current to the battery stack when the battery stack supplies power to the first load, and to collect the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack; the evaluation device is used to evaluate the single cell consistency of the battery stack based on the overall voltage and the single cell voltage.

[0023] In one possible embodiment, the stack is a hydrogen fuel cell stack; the system also includes: an air supply device, a hydrogen supply device, and a cooling device; the air supply device, the hydrogen supply device, and the cooling device are all connected to the hydrogen fuel cell stack; the air supply device is used to supply air to the hydrogen fuel cell stack; the hydrogen supply device is used to supply hydrogen to the hydrogen fuel cell stack; the cooling device is used to control the temperature of the hydrogen fuel cell stack through a coolant.

[0024] According to the third aspect provided by the present application, a device for evaluating the consistency of battery stack cells is provided, including: an acquisition module for acquiring the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack when the battery stack is in a power supply state and the battery stack is disturbed by a disturbance current; the battery stack is a fuel cell stack; and an evaluation module for evaluating the single cell consistency of the battery stack based on the overall voltage and the single cell voltage.

[0025] In a possible implementation, the above-mentioned evaluation module is specifically used to calculate the average cell voltage of multiple single cells in the battery stack based on the overall voltage; determine the voltage difference corresponding to each single cell based on the average cell voltage and the cell voltage of each single cell; and determine that the cell consistency evaluation result of the battery stack is qualified when the voltage difference corresponding to each single cell is less than the difference threshold.

[0026] In a possible implementation, the evaluation module is specifically used to calculate a plurality of reference voltage difference values ​​corresponding to each other at a plurality of moments of the first single cell battery; the reference voltage difference value is the absolute value of the difference between the first voltage at the corresponding moment and the second voltage at the corresponding moment; the first voltage is the single cell voltage of the first single cell battery; the second voltage is the average single cell voltage of a plurality of single cells; and the maximum value among the reference voltage difference values ​​corresponding to each of the plurality of moments is determined as the voltage difference value corresponding to the first single cell battery.

[0027] In a possible implementation, the device further includes: a determination module; the determination module is specifically used to determine whether the battery stack is in a stable power supply state based on the overall voltage of the battery stack when the battery stack is in a power supply state; the acquisition module is specifically used to acquire the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack when the battery stack is in a stable power supply state and the battery stack is disturbed by a disturbance current.

[0028] In a possible implementation, the above-mentioned determination module is specifically used to calculate the overall average voltage corresponding to the battery stack in multiple time periods based on the overall voltage of the battery stack; and determine whether the battery stack is in a stable power supply state based on the overall average voltage corresponding to the battery stack in multiple time periods.

[0029] In a possible implementation, the above-mentioned determination module is specifically used to determine the fluctuation amplitudes of multiple overall average voltages according to the overall average voltages corresponding to the battery stack in multiple time periods; the fluctuation amplitude is the difference between the maximum value and the minimum value of the multiple overall average voltages; when the fluctuation amplitudes of the multiple overall average voltages are less than the fluctuation amplitude threshold, it is determined that the battery stack is in a stable power supply state.

[0030] In one possible embodiment, the battery stack is a hydrogen fuel cell stack; the hydrogen fuel cell stack is also connected to an air supply device, a hydrogen supply device, and a cooling device; the above-mentioned determination module is specifically used to determine that the battery stack is in a stable power supply state when the fluctuation amplitude of multiple overall average voltages is less than the fluctuation amplitude threshold, if the air supply device, the hydrogen supply device, and the cooling device meet the following conditions: the fluctuation of the air intake flow rate is less than the first flow fluctuation threshold; the fluctuation of the air intake pressure is less than the first pressure fluctuation threshold; the fluctuation of the air intake temperature is less than the first temperature fluctuation threshold; the fluctuation of the hydrogen intake flow rate is less than the second flow fluctuation threshold; the fluctuation of the hydrogen intake pressure is less than the second pressure fluctuation threshold; the fluctuation of the hydrogen intake temperature is less than the second temperature fluctuation threshold; the fluctuation of the coolant inlet flow rate is less than the third flow fluctuation threshold; the fluctuation of the coolant inlet pressure is less than the third pressure fluctuation threshold; the fluctuation of the coolant inlet temperature is less than the third temperature fluctuation threshold.

[0031] In a possible implementation manner, the disturbance current is a constant frequency current or a variable frequency current.

[0032] According to the fourth aspect provided by the present application, an electronic device is provided, comprising: a processor; a memory for storing processor executable instructions; wherein the processor is configured to execute instructions to implement the method of the above-mentioned first aspect and any possible implementation manner thereof.

[0033] According to the fifth aspect provided by the present application, a computer-readable storage medium is provided. When the instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device is enabled to execute the method in the above-mentioned first aspect and any possible implementation method thereof.

[0034] According to the sixth aspect provided by the present application, a computer program product is provided, the computer program product comprising computer instructions, and when the computer instructions are executed on an electronic device, the electronic device executes the method of the above-mentioned first aspect and any possible implementation manner thereof.

[0035] Therefore, the above technical features of the present application have the following beneficial effects:

[0036] (1) By obtaining real-time data of the overall voltage of the stack and the single cell voltage of each single cell in the stack during the process of the stack being disturbed by external current, the single cell consistency of the stack is evaluated based on the real-time data of the overall voltage and the single cell voltage. Thus, by applying a disturbance current to the stack to make the current of the stack change rapidly, the overall voltage of the stack and the single cell voltage of each single cell in the stack during the process of the stack being disturbed by external current are obtained. The single cell consistency of the stack is evaluated based on the changes in the overall voltage of the stack and the single cell voltage of each single cell in the stack, thereby achieving the evaluation of the single cell consistency of the stack.

[0037] (2) The average value of the overall voltage of the battery stack can reflect the concentration trend of the overall voltage of the battery stack. The present application can more accurately evaluate the consistency between single cells by calculating the average single cell voltage and comparing the voltage difference between the single cell voltage and the average single cell voltage. At the same time, comparing the voltage difference between the single cell voltage and the average single cell voltage does not require a complex data processing process, and can obtain the evaluation result more quickly, thereby improving the evaluation efficiency.

[0038] (3) The present application uses the maximum value of the voltage difference within a period of time as the voltage difference corresponding to each single cell, so that the obtained voltage difference can more accurately characterize the performance of the battery, and further make the single cell consistency evaluation result of the battery stack more accurate.

[0039] (4) The present application can determine whether the battery stack is in a stable power supply state, and obtain the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack when it is in a stable power supply state, thereby improving the accuracy of the overall voltage and single cell voltage results.

[0040] (5) When the battery stack is in a stable power supply state, the voltage output by the battery stack is stable. The present application determines whether the voltage output by the battery stack is stable by calculating the overall average voltage in multiple time periods and comparing the overall average voltage in multiple time periods, and then determines whether the battery stack is in a stable power supply state. Since the voltage is a direct reflection of the operating state of the battery stack, the battery stack is determined to be in a stable power supply state by real-time monitoring of the voltage changes. This method is simple and convenient, and it can clearly show whether the battery stack is in a stable power supply state.

[0041] (6) When the battery stack is in a stable power supply state, the voltage output by the battery stack is stable. However, the output voltage is not a fixed value, but fluctuates within a certain range. The present application can determine the fluctuation amplitude in multiple time periods. If the fluctuation amplitude is less than the fluctuation amplitude threshold, it is determined that the voltage output by the battery stack is stable, and then it is determined that the battery stack is in a stable power supply state. This method is easy to operate and has a simple calculation process, which can improve the efficiency of determining that the battery stack is in a stable power supply state.

[0042] (7) In the case where the battery stack is a hydrogen fuel cell battery stack, when the battery stack is powered, an air supply device, a hydrogen supply device, and a cooling device are required to provide external conditions for the battery stack. Therefore, the battery stack being in a stable power supply state also includes the stability of various data of the air supply device, the hydrogen supply device, and the cooling device. The present application can determine whether the battery stack is in a stable power supply state by judging whether various data of the air supply device, the hydrogen supply device, and the cooling device are stable, so that the result of the battery stack being in a stable power supply state is more accurate and comprehensive.

[0043] (8) When the disturbance current is a variable frequency current, applying the variable frequency current within a period of time is equivalent to repeatedly applying the disturbance current. When the disturbance current is a fixed frequency current, by setting the time interval for applying the disturbance current, multiple changes in current can also be achieved within a period of time, which is equivalent to repeatedly applying the disturbance current. The present application simulates multiple applications of the disturbance current by applying a fixed frequency current or a variable frequency current, which is equivalent to multiple evaluations of the cell consistency of the battery stack, thereby improving the accuracy of the cell consistency evaluation results.

[0044] It should be noted that the technical effects brought about by any implementation method in the second to sixth aspects can refer to the technical effects brought about by the corresponding implementation method in the first aspect, and will not be repeated here.

[0045] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification are used to explain the principles of the present application, and do not constitute an improper limitation on the present application.

[0047] Figure 1 is a structural schematic diagram of a system for evaluating the consistency of a battery stack cell according to an exemplary embodiment;

[0048] Figure 2 is a schematic diagram showing the connection between a second load and a fuel cell stack according to an exemplary embodiment;

[0049] Figure 3 is a structural schematic diagram of another battery stack cell consistency evaluation system according to an exemplary embodiment;

[0050] Figure 4 is a flow chart of a method for evaluating consistency of a battery stack cell according to an exemplary embodiment;

[0051] Figure 5 is a flow chart of another method for evaluating consistency of a battery stack cell according to an exemplary embodiment;

[0052] Figure 6 is a diagram showing evaluation results of battery stack cell consistency according to an exemplary embodiment;

[0053] Figure 7 is a flow chart of another method for evaluating consistency of a battery stack cell according to an exemplary embodiment;

[0054] Figure 8 is a flow chart of another method for evaluating consistency of a battery stack cell according to an exemplary embodiment;

[0055] Fig. 9 is a block diagram of a device for evaluating consistency of a battery stack cell according to an exemplary embodiment;

[0056] Fig.10 It is a block diagram of an electronic device according to an exemplary embodiment. DETAILED DESCRIPTION

[0057] In order to enable ordinary persons in the art to better understand the technical solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings.

[0058] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.

[0059] Fuel cells are used as on-board power devices for electric vehicles. In actual use, since the output power of a fuel cell is limited, multiple fuel cells are often connected in series to form a fuel cell stack (fuel cell stack) to increase the output power of the fuel cell stack.

[0060] Since the performance of each single cell in the battery stack is different, there are also differences in the voltage between each single cell. If the difference between the voltages is large, the external power output capacity of the battery stack will be greatly reduced and the battery aging will be accelerated.

[0061] Therefore, how to evaluate the cell consistency of the fuel cell stack is an urgent problem that needs to be solved.

[0062] Based on the above problems, the present application provides a method, system, device and storage medium for evaluating the consistency of battery stack cells, so as to at least solve the technical problem that it takes a long time to evaluate the consistency of battery stack cells in the related art. By obtaining real-time data of the overall voltage of the battery stack and the cell voltage of each single cell in the battery stack during the process of the battery stack being disturbed by an external current, the cell consistency of the battery stack is evaluated according to the real-time data of the overall voltage and the cell voltage. Thus, by applying a disturbance current to the battery stack to make the current of the battery stack change rapidly, the overall voltage of the battery stack and the cell voltage of each single cell in the battery stack during the process of the battery stack being disturbed by an external current will change with the current in the battery stack, and the cell consistency of the battery stack is evaluated according to the changes in the overall voltage of the battery stack and the cell voltage of each single cell in the battery stack, thereby achieving the evaluation of the cell consistency of the battery stack.

[0063] For ease of understanding, the stack cell consistency evaluation method, system, device and storage medium provided in the present application are specifically introduced below in conjunction with the accompanying drawings.

[0064] Figure 1 FIG. 1 is a schematic diagram of a system for evaluating the consistency of a battery stack cell according to an exemplary embodiment. Figure 1 As shown, the battery stack monomer consistency evaluation system 100 includes: a first load 110 , a battery stack 120 , a second load 130 and an evaluation device 140 .

[0065] Among them, the first load 110 is respectively connected to the positive and negative electrodes of the battery stack 120; the second load 130 is respectively connected to the positive and negative electrodes of the battery stack 120, and the second load 130 is respectively connected to the positive and negative electrodes of each single cell in the battery stack 120, and the evaluation device 140 is connected to the second load 130.

[0066] Figure 2 FIG. 1 is a schematic diagram showing the connection between the second load and the battery stack according to an exemplary embodiment. Figure 2 As shown, the battery stack includes N single cells, and the second load 130 is connected to the total positive node and the total negative node of the battery stack and the positive and negative nodes of each single cell through a wiring harness. Wherein N is a positive integer.

[0067] The second load 130 is used to apply a disturbance current to the stack 120 and collect the overall voltage of the stack and the single cell voltage of each single cell in the stack when the stack 120 supplies power to the first load 110 , wherein the stack 120 is a fuel cell stack.

[0068] The evaluation device 140 is used to evaluate the cell consistency of the stack according to the overall voltage and the cell voltage. The specific process of the evaluation device 140 evaluating the cell consistency of the stack can be referred to the evaluation method of the cell consistency of the stack below, which will not be repeated here.

[0069] Figure 3 FIG. 1 is a schematic diagram of a structure of another battery stack cell consistency evaluation system according to an exemplary embodiment. Figure 3 As shown, when the stack 120 is a hydrogen fuel cell stack, the stack monomer consistency evaluation system further includes: an air supply device 310 , a hydrogen supply device 320 , and a cooling device 330 .

[0070] Among them, the air supply device 310, the hydrogen supply device 320, and the cooling device 330 are all connected to the hydrogen fuel cell stack; the air supply device 310 is used to supply air to the hydrogen fuel cell stack; the hydrogen supply device 320 is used to supply hydrogen to the hydrogen fuel cell stack; the cooling device 330 is used to control the temperature of the hydrogen fuel cell stack through coolant.

[0071] The execution subject of the method for evaluating the consistency of battery stack cells provided in the embodiment of the present application is an evaluation device for the consistency of battery stack cells, and the evaluation device for the consistency of battery stack cells can be configured in an electronic device so that the electronic device can realize the function of evaluating the consistency of battery stack cells. Optionally, the electronic device can be the evaluation device 140 in the above-mentioned evaluation system for the consistency of battery stack cells; or, the electronic device can also be a functional module for realizing the consistency evaluation of battery stack cells in the evaluation device of the above-mentioned evaluation system for the consistency of battery stack cells, etc. The embodiment of the present application does not limit this.

[0072] Figure 4 is a flow chart of a method for evaluating the consistency of a battery stack cell according to an exemplary embodiment. Figure 4 As shown, the method for evaluating the consistency of the battery stack monomer includes the following steps:

[0073] S401, when the battery stack is in a power supply state and the battery stack is disturbed by a disturbance current, obtaining the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack.

[0074] In the embodiment of the present application, the stack is a fuel cell stack.

[0075] Wherein, the disturbance current is a variable frequency current, and the frequency of the disturbance current is not fixed, that is, frequency sweeping. In the case where the frequency of the disturbance current is not fixed, it is necessary to set the variation period of the disturbance frequency. For example, the frequency range of the disturbance current is 1000-0.1Hz, and the variation period t=60s / dec.

[0076] Optionally, the frequency of the disturbance current may also be fixed, that is, a constant-frequency current. When the disturbance current is applied, the time interval for applying the disturbance current should be greater than an interval threshold. Specifically, the interval threshold is not less than 5s.

[0077] As a possible implementation method, as described in the above-mentioned battery stack cell consistency evaluation system, the battery stack supplies power to the first load, the second load applies a disturbance current to the battery stack, and collects the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack, the second load sends the collected overall voltage and single cell voltage to the evaluation device, and the evaluation device receives the overall voltage and single cell voltage sent by the second load.

[0078] S402, evaluating the cell consistency of the stack based on the overall voltage and the cell voltage.

[0079] As a possible implementation method, the average voltage of the stack is used to reflect the overall level of the stack voltage. The evaluation device determines the average value of the overall voltage of the stack and the average value of the single cell voltage based on the overall voltage and single cell voltage over a period of time, and compares the difference between the two average values. If the difference is within a preset range, it means that the single cell consistency of the stack is qualified. The smaller the difference, the more balanced the voltage of the stack and the better the single cell consistency of the stack.

[0080] As another possible implementation method, the standard deviation is used to measure the degree of dispersion (i.e. consistency) of the stack voltage or the cell voltage. The evaluation device calculates the standard deviation of each cell in the stack based on the overall voltage and the cell voltage. If the standard deviation is within the preset range, it means that the cell consistency of the stack is qualified. The smaller the standard deviation, the closer the voltage of each cell in the stack is, and the better the cell consistency of the stack is.

[0081] As another possible implementation, the evaluation device calculates the cell voltage difference between any two adjacent single cells based on the cell voltage, and compares the cell voltage difference with a set threshold. If the cell voltage difference does not exceed the set threshold, it indicates that the cell consistency of the battery stack is qualified.

[0082] Furthermore, when the result of the cell consistency is unqualified, the serial number of the unqualified single cell in the battery stack is determined based on the overall voltage and the single cell voltage, so as to facilitate battery replacement or further testing of the single cell.

[0083] The method for evaluating the consistency of the battery stack cells in the embodiment of the present application obtains the real-time data of the overall voltage of the battery stack and the cell voltage of each single cell in the battery stack during the process of the battery stack being disturbed by the disturbance current, and evaluates the consistency of the cells of the battery stack according to the real-time data of the overall voltage and the cell voltage. Thus, by applying a disturbance current to the battery stack to make the current of the battery stack change rapidly, the overall voltage of the battery stack and the cell voltage of each single cell in the battery stack during the process of the battery stack being disturbed by the external current will change with the current in the battery stack, and the consistency of the cells of the battery stack will be evaluated according to the changes in the overall voltage of the battery stack and the cell voltage of each single cell in the battery stack, thereby achieving the evaluation of the consistency of the cells of the battery stack.

[0084] In addition, when the disturbance current in the present application is a variable frequency current, applying the variable frequency current within a period of time is equivalent to repeatedly applying the disturbance current. When the disturbance current is a fixed frequency current, by setting the time interval for applying the disturbance current, it is also possible to achieve multiple changes in current within a period of time, which is equivalent to repeatedly applying the disturbance current. By applying a variable frequency current to simulate multiple applications of the disturbance current, it is equivalent to repeatedly evaluating the consistency of the cells of the battery stack, thereby improving the accuracy of the cell consistency evaluation results.

[0085] It should be noted that the performance parameters of the battery (voltage, power, etc.) can change significantly in the high current range, making it easier to evaluate the consistency of single cells. Therefore, when evaluating the single cell consistency of the battery stack, the prior art pulls the current of the battery stack to the high current range and then evaluates the single cell consistency of the battery stack.

[0086] However, directly evaluating the consistency of cells after the stack current is pulled to a high current range will be affected by accidental factors, and the error of the evaluation result will be particularly large. Therefore, it is usually necessary to wait for the stack current to run stably for a period of time before evaluating, which can eliminate the influence of accidental factors and reduce the error of the evaluation result.

[0087] Compared with the prior art, the technical solution of the present application can evaluate the cell consistency of the stack based on the real-time data of the overall voltage of the stack and the cell voltage of each single cell in the stack when the stack is disturbed by the disturbance current. The process of applying the disturbance current is equivalent to a load change process. In this process, because the performance of each single cell in the stack is different, each single cell will have a different voltage response, and this voltage response is exactly a reflection of the cell consistency. Therefore, compared with the prior art, this solution does not need to wait for the stack to stabilize for a period of time. Therefore, compared with the prior art, the present application does not need to wait for the stack to stabilize for a period of time, that is, it can shorten the time for evaluating the consistency of the cells.

[0088] At the same time, since the disturbance current in this application is a variable frequency current or a fixed frequency current, by setting the time interval for applying the fixed frequency current or the frequency change cycle of the variable frequency current, it is equivalent to repeatedly applying the disturbance current. Repeatedly applying the disturbance current is equivalent to repeatedly evaluating the consistency of the single cells of the battery stack, which can eliminate the influence of accidental factors and reduce the error of the evaluation result. Compared with the prior art, this application can also achieve the effect of reducing the error of the evaluation result.

[0089] In addition, it is understandable that before evaluating the cell consistency of the battery stack, some battery stacks have poor cell consistency. If the battery stack with poor cell consistency is directly loaded to the high current range according to the method of the prior art, the battery will be damaged. In the technical solution of this application, the battery stack works in the low current range, and this method of evaluating the battery stack with poor cell consistency is not likely to damage the battery.

[0090] In some embodiments, the cell consistency of the stack is generally evaluated based on the difference between the average cell voltage of the stack and the cell voltage. Figure 5 is a flow chart of another method for evaluating the consistency of a battery stack cell according to an exemplary embodiment. Figure 5 As shown, S402 provided in the embodiment of the present application includes the following steps:

[0091] S501, calculating the average cell voltage of multiple cells in the battery stack according to the overall voltage.

[0092] S502, determining a voltage difference corresponding to each single cell according to the average single cell voltage and the single cell voltage of each single cell.

[0093] As a possible implementation manner, the evaluation device determines the difference between the average cell voltage at any time during the application of the disturbance current and the cell voltage of each single cell, and uses the absolute value of the difference as the voltage difference corresponding to each single cell.

[0094] As another possible implementation method, the evaluation device calculates multiple reference voltage difference values ​​corresponding to each other at multiple moments of the first single cell; the reference voltage difference value is the absolute value of the difference between the first voltage at the corresponding moment and the second voltage at the corresponding moment; and the maximum value among the reference voltage difference values ​​corresponding to each of the multiple moments is determined as the voltage difference value corresponding to the first single cell.

[0095] The first single cell is any single cell in the battery stack, the first voltage is the single cell voltage of the first single cell, and the second voltage is the average single cell voltage of multiple single cells.

[0096] Exemplarily, the voltage difference between different cell voltages and the average cell voltage at any time is calculated, and the calculation process is shown in formula (1) and formula (2):

[0097]

[0098] S n =max(S ni ) Formula (2)

[0099] Among them, S ni represents the voltage difference corresponding to the first single cell at different times, n represents the single cell number, i represents the time, Represents the average cell voltage, S n represents the voltage difference corresponding to the first single cell. For example, if the serial number of the first single cell is 1, then S ni For S 1i , S n is S1.

[0100] S503, when the voltage difference corresponding to each single cell is less than the difference threshold, determining that the single cell consistency evaluation result of the battery stack is qualified.

[0101] Figure 6 is a diagram showing the evaluation result of the consistency of a battery stack according to an exemplary embodiment. For example, the difference threshold is 30mV, Figure 6 The horizontal axis of the middle bar graph represents the cell number, and the vertical axis represents the voltage difference corresponding to each cell. Figure 6 It can be clearly seen that the voltage difference corresponding to the first single cell exceeds 60mV, which is much larger than the difference threshold of 30mV. The single cell consistency assessment result of the battery stack is unqualified.

[0102] In some embodiments, in order to ensure the accuracy of the evaluation result, before applying the disturbance current to the battery stack, it should be ensured that the battery stack is in a stable power supply state. Therefore, before the second load applies the disturbance current to the battery stack, the evaluation device should determine that the battery stack is in a stable power supply state. The specific process includes the following steps:

[0103] Step 1a: when the fuel cell stack is in a power supply state, determine whether the fuel cell stack is in a stable power supply state according to the overall voltage of the fuel cell stack.

[0104] Furthermore, when the battery stack is in a stable power supply state and the battery stack is disturbed by a disturbance current, the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack are obtained.

[0105] Optionally, if the disturbance current value is too small, the overall voltage and single cell voltage will not change significantly, which is not conducive to evaluating the single cell consistency of the battery stack. Therefore, the second load can obtain the first current of the battery stack under a stable power supply state. Before applying the disturbance current, the preset value of the disturbance current can be determined by determining the size of the first current.

[0106] Optionally, the first current can be set to exceed 30% of the rated current of the battery stack, and the disturbance current should be no less than 5% of the first current. Exemplarily, the first current can be set to 235.4A, and the disturbance current can be set to 11.77A.

[0107] In some embodiments, the fuel cell stack being in a stable power supply state includes the voltage of the fuel cell stack remaining stable for a period of time. Figure 7 is a flow chart of another method for evaluating the consistency of a battery stack cell according to an exemplary embodiment. Figure 7 As shown, determining whether the battery stack is in a stable power supply state includes the following steps:

[0108] S701, calculating the overall average voltage of the fuel cell stack corresponding to each of multiple time periods according to the overall voltage of the fuel cell stack.

[0109] As a possible implementation method, the overall voltage of the battery stack within a preset time period is obtained, the preset time period is divided into multiple time periods, and the overall average voltage corresponding to each time period is calculated.

[0110] S702, determining whether the fuel cell stack is in a stable power supply state according to the overall average voltage corresponding to each of the fuel cell stacks in multiple time periods.

[0111] As a possible implementation method, the fluctuation amplitudes of multiple overall average voltages are determined according to the overall average voltages corresponding to the battery stack in multiple time periods; the fluctuation amplitude is the difference between the maximum and minimum values ​​of the multiple overall average voltages; when the fluctuation amplitudes of the multiple overall average voltages are less than the fluctuation amplitude threshold, it is determined that the battery stack is in a stable power supply state.

[0112] As another possible implementation, when the overall average voltage corresponding to any time period is within a reference voltage range corresponding to the time period, it is determined that the battery stack is in a stable state; the reference voltage range is determined based on the overall average voltage corresponding to the reference time period and the fluctuation amplitude threshold; the reference time period is a time period before the time period corresponding to the reference voltage.

[0113] In some embodiments, the battery stack is a hydrogen fuel cell stack, which is also connected to an air supply device, a hydrogen supply device, and a cooling device; the battery stack is in a stable power supply state and the external conditions of the battery stack remain stable for a period of time.

[0114] Further, when the fluctuation amplitudes of multiple overall average voltages are smaller than the fluctuation amplitude threshold, it is determined that the fuel cell stack is in a stable power supply state, including: when the fluctuation amplitudes of multiple overall average voltages are smaller than the fluctuation amplitude threshold, if the air supply device, the hydrogen supply device, and the cooling device meet the following conditions, it is determined that the fuel cell stack is in a stable power supply state.

[0115] Among them, the conditions include: the fluctuation of air intake flow rate is less than the first flow fluctuation threshold; the fluctuation of air intake pressure is less than the first pressure fluctuation threshold; the fluctuation of air intake temperature is less than the first temperature fluctuation threshold; the fluctuation of hydrogen intake flow rate is less than the second flow fluctuation threshold; the fluctuation of hydrogen intake pressure is less than the second pressure fluctuation threshold; the fluctuation of hydrogen intake temperature is less than the second temperature fluctuation threshold; the fluctuation of coolant inlet flow rate is less than the third flow fluctuation threshold; the fluctuation of coolant inlet pressure is less than the third pressure fluctuation threshold; the fluctuation of coolant inlet temperature is less than the third temperature fluctuation threshold.

[0116] As a possible implementation method, the evaluation system for the consistency of the fuel cell stack also includes: a data acquisition device, which collects air intake flow, air intake pressure, air intake temperature, hydrogen intake flow, hydrogen intake pressure, hydrogen intake temperature, coolant inlet flow, coolant inlet pressure and coolant inlet temperature; the evaluation device obtains these data and compares them with the fluctuation thresholds corresponding to the preset data. If they are all less than the fluctuation thresholds, it is determined that the fuel cell stack is in a stable power supply state.

[0117] Among them, data acquisition equipment includes but is not limited to temperature sensors, pressure sensors and flow meters.

[0118] Figure 8 1 is a flow chart of another method for evaluating the consistency of a battery stack cell according to an exemplary embodiment, comprising the following steps:

[0119] S801, connecting the fuel cell stack, the fuel cell stack test system and the second load in a prescribed manner.

[0120] Exemplarily, the stack is a hydrogen fuel cell stack, and the stack is connected to the stack test system and the second load in the following manner: Figure 1 and Figure 3 shown.

[0121] S802, preset various key parameters according to the characteristics of the battery stack.

[0122] As a possible implementation method, the key parameters are the data of the above-mentioned air supply device, hydrogen supply device, and cooling device.

[0123] S803, the battery stack operates at the first current point A1.

[0124] Exemplarily, the first current point A1 is the first current mentioned above.

[0125] S804: Is the battery stack in a stable state?

[0126] As a possible implementation, if the fuel cell stack is in a stable state, step S805 is executed; if the fuel cell stack is in an unstable state, the process returns to step S803, and the fuel cell stack continues to operate at the first current point A1.

[0127] S805: The second load applies a disturbance current A2.

[0128] Exemplarily, the disturbance current A2 is the disturbance current mentioned above.

[0129] S806, calculation S n =max(S ni ).

[0130] Exemplarily, step S806 may refer to the implementation process of S502 in the above embodiment, which will not be described in detail here.

[0131] S807, all S n Are they all less than S?

[0132] For example, S is the difference threshold, and in all S n If all are less than S, step S808 is executed, and the cell consistency evaluation result of the battery stack is qualified; if any S n If it is not less than S, step S809 is executed and the cell consistency evaluation result of the fuel cell stack is unqualified.

[0133] S808, the battery stack consistency is qualified.

[0134] S809, the battery stack consistency is unqualified.

[0135] The above mainly introduces the solution provided by the embodiment of the present application from the perspective of the method. In order to achieve the above functions, the evaluation device or electronic device for the consistency of the battery stack cell includes a hardware structure and / or software module corresponding to the execution of each function. It should be easily appreciated by those skilled in the art that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0136] The embodiment of the present application can divide the functional modules of the evaluation device or electronic device for the consistency of the battery stack cells according to the above method. For example, the evaluation device or electronic device for the consistency of the battery stack cells may include various functional modules corresponding to the various functional divisions, or two or more functions may be integrated into one processing module. The above-mentioned integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical functional division. There may be other division methods in actual implementation.

[0137] Fig. 9 is a block diagram of a device for evaluating the consistency of a battery stack cell according to an exemplary embodiment. Fig. 9 The evaluation device for the consistency of the battery stack cells includes: an acquisition module 910, which is used to obtain the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack when the battery stack is in a power supply state and the battery stack is disturbed by a disturbance current; the battery stack is a fuel cell battery stack; and an evaluation module 920, which is used to evaluate the single cell consistency of the battery stack based on the overall voltage and the single cell voltage.

[0138] In a possible implementation, the above-mentioned evaluation module 920 is specifically used to calculate the average cell voltage of multiple single cells in the battery stack based on the overall voltage; determine the voltage difference corresponding to each single cell based on the average cell voltage and the cell voltage of each single cell; and determine that the cell consistency evaluation result of the battery stack is qualified when the voltage difference corresponding to each single cell is less than the difference threshold.

[0139] In a possible implementation, the evaluation module 920 is specifically used to calculate a plurality of reference voltage difference values ​​corresponding to each other at a plurality of moments of the first single cell battery; the reference voltage difference value is the absolute value of the difference between the first voltage at the corresponding moment and the second voltage at the corresponding moment; the first voltage is the single cell voltage of the first single cell battery; the second voltage is the average single cell voltage of a plurality of single cells; and the maximum value among the reference voltage difference values ​​corresponding to each of the plurality of moments is determined as the voltage difference value corresponding to the first single cell battery.

[0140] In a possible implementation, the device further includes: a determination module; the determination module is specifically used to determine whether the battery stack is in a stable power supply state based on the overall voltage of the battery stack when the battery stack is in a power supply state; the acquisition module is specifically used to acquire the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack when the battery stack is in a stable power supply state and the battery stack is disturbed by a disturbance current.

[0141] In a possible implementation, the above-mentioned determination module is specifically used to calculate the overall average voltage corresponding to the battery stack in multiple time periods based on the overall voltage of the battery stack; and determine whether the battery stack is in a stable power supply state based on the overall average voltage corresponding to the battery stack in multiple time periods.

[0142] In a possible implementation, the above-mentioned determination module is specifically used to determine the fluctuation amplitudes of multiple overall average voltages according to the overall average voltages corresponding to the battery stack in multiple time periods; the fluctuation amplitude is the difference between the maximum value and the minimum value of the multiple overall average voltages; when the fluctuation amplitudes of the multiple overall average voltages are less than the fluctuation amplitude threshold, it is determined that the battery stack is in a stable power supply state.

[0143] In one possible embodiment, the battery stack is a hydrogen fuel cell stack; the hydrogen fuel cell stack is also connected to an air supply device, a hydrogen supply device, and a cooling device; the above-mentioned determination module is specifically used to determine that the battery stack is in a stable power supply state when the fluctuation amplitude of multiple overall average voltages is less than the fluctuation amplitude threshold, if the air supply device, the hydrogen supply device, and the cooling device meet the following conditions: the fluctuation of the air intake flow rate is less than the first flow fluctuation threshold; the fluctuation of the air intake pressure is less than the first pressure fluctuation threshold; the fluctuation of the air intake temperature is less than the first temperature fluctuation threshold; the fluctuation of the hydrogen intake flow rate is less than the second flow fluctuation threshold; the fluctuation of the hydrogen intake pressure is less than the second pressure fluctuation threshold; the fluctuation of the hydrogen intake temperature is less than the second temperature fluctuation threshold; the fluctuation of the coolant inlet flow rate is less than the third flow fluctuation threshold; the fluctuation of the coolant inlet pressure is less than the third pressure fluctuation threshold; the fluctuation of the coolant inlet temperature is less than the third temperature fluctuation threshold.

[0144] In a possible implementation manner, the disturbance current is a constant frequency current or a variable frequency current.

[0145] Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0146] Fig.10 FIG. 1 is a block diagram of an electronic device according to an exemplary embodiment. Fig.10 As shown, the electronic device 1000 includes but is not limited to: a processor 1001 and a memory 1002 .

[0147] The memory 1002 is used to store executable instructions of the processor 1001. It can be understood that the processor 1001 is configured to execute instructions to implement the method for evaluating the consistency of the battery stack cells in the above embodiment.

[0148] It should be noted that those skilled in the art can understand that Fig.10 The electronic device structure shown in the figure does not constitute a limitation on the electronic device, and the electronic device may include Fig.10 More or fewer components may be shown, or certain components may be combined, or the components may be arranged differently.

[0149] The processor 1001 is the control center of the electronic device. It uses various interfaces and lines to connect various parts of the entire electronic device. By running or executing software programs and / or modules stored in the memory 1002, and calling data stored in the memory 1002, it performs various functions of the electronic device and processes data, thereby monitoring the electronic device as a whole. The processor 1001 may include one or more processing units. Optionally, the processor 1001 may integrate an application processor and a modem processor, wherein the application processor mainly processes the operating system, user interface, and application programs, and the modem processor mainly processes wireless communications. It is understandable that the above-mentioned modem processor may not be integrated into the processor 1001.

[0150] The memory 1002 may be used to store software programs and various data. The memory 1002 may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application program required by at least one functional module (such as a determination unit, a processing unit, etc.), etc. In addition, the memory 1002 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0151] In an exemplary embodiment, a computer-readable storage medium including instructions is also provided, such as a memory 1002 including instructions. The above instructions can be executed by the processor 1001 of the electronic device 1000 to implement the method in the above embodiment.

[0152] In actual implementation, Fig. 9 The functions of the acquisition module 910 and the evaluation module 920 in Fig.10 The processor 1001 in the embodiment calls the computer program stored in the memory 1002 to implement. The specific execution process can refer to the description of the method part in the above embodiment, which will not be repeated here.

[0153] Optionally, the computer-readable storage medium may be a non-temporary computer-readable storage medium, for example, the non-temporary computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc.

[0154] In an exemplary embodiment, the present application also provides a computer program product including one or more instructions, and the one or more instructions can be executed by the processor 1001 of the electronic device to complete the method in the above embodiment.

[0155] It should be noted that when the instructions in the above-mentioned computer-readable storage medium or one or more instructions in the computer program product are executed by the processor of the electronic device, the various processes of the above-mentioned method embodiment are implemented, and the same technical effect as the above-mentioned method can be achieved. To avoid repetition, they will not be repeated here.

[0156] Through the description of the above implementation methods, technical personnel in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0157] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0158] The units described as separate components may or may not be physically separated, and the components shown as units may be one physical unit or multiple physical units, that is, they may be located in one place or distributed in multiple different places. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0159] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0160] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes to the prior art or the full classification part or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium, including a number of instructions to enable a device (which can be a single-chip microcomputer, chip, etc.) or a processor (processor) to execute the full classification part or part of the steps of each embodiment method of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, ROM, RAM, disk or CD and other media that can store program code.

[0161] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto, and any changes or substitutions within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for evaluating the consistency of a battery stack, characterized in that: include: When the battery stack is in a power supply state and the battery stack is disturbed by a disturbance current, obtaining the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack; the battery stack is a fuel cell battery stack; The cell consistency of the stack is evaluated based on the overall voltage and the cell voltage.

2. The method according to claim 1, characterized in that The step of evaluating the cell consistency of the stack according to the overall voltage and the cell voltage includes: Calculating an average cell voltage of a plurality of cells in the battery stack according to the overall voltage; Determine a voltage difference corresponding to each single cell according to the average single cell voltage and the single cell voltage of each single cell; When the voltage difference corresponding to each single cell is less than the difference threshold, it is determined that the single cell consistency evaluation result of the battery stack is qualified.

3. The method according to claim 2, characterized in that For any first single cell in the battery stack, determining the voltage difference corresponding to each single cell according to the average single cell voltage and the single cell voltage of each single cell includes: Calculate a plurality of reference voltage differences corresponding to the first single cell at a plurality of moments; the reference voltage difference is the absolute value of the difference between the first voltage at the corresponding moment and the second voltage at the corresponding moment; the first voltage is the single cell voltage of the first single cell; the second voltage is the average single cell voltage of the plurality of single cells; The maximum value of the reference voltage difference values ​​corresponding to the multiple moments is determined as the voltage difference value corresponding to the first single cell.

4. The method according to claim 1, characterized in that: When the battery stack is in a power supply state and the battery stack is disturbed by a disturbance current, before obtaining the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack, the method further includes: When the battery stack is in a power supply state, determining whether the battery stack is in a stable power supply state according to the overall voltage of the battery stack; The step of obtaining the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack when the battery stack is in a power supply state and the battery stack is disturbed by a disturbance current comprises: When the battery stack is in a stable power supply state and the battery stack is disturbed by a disturbance current, the overall voltage of the battery stack and the single cell voltage of each single cell in the battery stack are obtained.

5. The method according to claim 4, characterized in that The determining, according to the overall voltage of the battery stack, whether the battery stack is in a stable power supply state comprises: Calculating the overall average voltage of the battery stack corresponding to each of the plurality of time periods according to the overall voltage of the battery stack; Whether the battery stack is in a stable power supply state is determined according to the overall average voltages corresponding to the battery stack in multiple time periods.

6. The method according to claim 5, characterized in that The determining whether the battery stack is in a stable power supply state according to the overall average voltages corresponding to the battery stack in multiple time periods includes: Determine the fluctuation amplitudes of the plurality of overall average voltages according to the overall average voltages corresponding to the stack in the plurality of time periods; the fluctuation amplitude is the difference between the maximum value and the minimum value of the plurality of overall average voltages; When the fluctuation amplitudes of the plurality of overall average voltages are smaller than a fluctuation amplitude threshold, it is determined that the fuel cell stack is in a stable power supply state.

7. The method according to claim 6, characterized in that The stack is a hydrogen fuel cell stack; the hydrogen fuel cell stack is also connected to an air supply device, a hydrogen supply device, and a cooling device; When the fluctuation amplitudes of the plurality of overall average voltages are less than a fluctuation amplitude threshold, determining that the battery stack is in a stable power supply state includes: When the fluctuation amplitudes of the plurality of overall average voltages are less than the fluctuation amplitude threshold, if the air supply device, the hydrogen supply device, and the cooling device meet the following conditions, it is determined that the fuel cell stack is in a stable power supply state: The fluctuation of the air intake flow rate is less than a first flow fluctuation threshold; The fluctuation of the air intake pressure is less than a first pressure fluctuation threshold; The fluctuation of the air intake temperature is less than a first temperature fluctuation threshold; The fluctuation of the hydrogen intake flow rate is less than a second flow fluctuation threshold; The fluctuation of the hydrogen inlet pressure is less than a second pressure fluctuation threshold; The fluctuation of the hydrogen intake temperature is less than a second temperature fluctuation threshold; The fluctuation of the coolant inlet flow rate is less than a third flow fluctuation threshold; The fluctuation of the coolant inlet pressure is less than the third pressure fluctuation threshold; The fluctuation of the coolant inlet temperature is less than the third temperature fluctuation threshold.

8. The method according to any one of claims 1 to 7, characterized in that: The disturbance current is a constant frequency current or a variable frequency current.

9. A system for evaluating the consistency of a battery stack, characterized in that: include: A first load, a battery stack, a second load, and an evaluation device; Wherein, the first load is connected to the positive and negative electrodes of the battery stack respectively; The second load is connected to the positive and negative electrodes of the battery stack respectively, and the second load is connected to the positive and negative electrodes of each single cell in the battery stack respectively; The second load is used to apply a disturbance current to the fuel cell stack and collect the overall voltage of the fuel cell stack and the single cell voltage of each single cell in the fuel cell stack when the fuel cell stack supplies power to the first load; the evaluation device is used to evaluate the single cell consistency of the fuel cell stack based on the overall voltage and the single cell voltage.

10. The system according to claim 9, characterized in that The stack is a hydrogen fuel cell stack; the system further comprises: an air supply device, a hydrogen supply device, and a cooling device; the air supply device, the hydrogen supply device, and the cooling device are all connected to the hydrogen fuel cell stack; The air supply device is used to supply air to the hydrogen fuel cell stack; The hydrogen supply device is used to supply hydrogen to the hydrogen fuel cell stack; The cooling device is used to control the temperature of the hydrogen fuel cell stack through a coolant.

11. An electronic device, characterized in that: include: processor; a memory for storing instructions executable by the processor; The processor is configured to execute the instructions to implement the method according to any one of claims 1 to 8.

12. A computer-readable storage medium, characterized in that: When the computer-executable instructions stored in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device can perform the method as claimed in any one of claims 1 to 8.

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