Battery aging degree evaluation method, system and device and electronic equipment

Abstract

The invention provides a battery aging degree evaluation method, system and device and electronic equipment, and is applied to the technical field of batteries. The method comprises the steps that after it is monitored that the battery voltage of a lead-acid storage battery monomer is smaller than preset battery cut-off voltage, the target open-circuit voltage of the lead-acid storage battery monomer is obtained, and the target open-circuit voltage is determined according to the mass of components in gas separated out of an air overflow valve of the lead-acid storage battery monomer; determining a target charge state corresponding to the target open-circuit voltage based on a preset corresponding relationship between the charge state and the open-circuit voltage; according to the target charge state and the rated capacity of the lead-acid storage battery monomer, the battery health state of the lead-acid storage battery monomer is determined, and the battery health state reflects the battery aging degree. According to the application, the open-circuit voltage of the lead-acid storage battery monomer is determined according to the component quality in the gas separated out by the gas overflow valve, the accuracy of the open-circuit voltage is improved, the accuracy of a battery aging degree evaluation result is further improved, and online monitoring is facilitated.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and in particular, to a method, system, device, and electronic device for evaluating the aging degree of a battery. Background Art

[0002] Lead-acid batteries are applied to the DC power supply system of substations due to their advantages of safety and reliability, stable performance, long service life, and "maintenance-free". In the later stage of charging of lead-acid batteries, since the chemical reaction of the active substances inside the battery is basically completed, the excess electricity causes a side reaction of electrolyzing water in the battery, generating hydrogen and oxygen at both poles of the battery respectively. Under normal circumstances, the oxygen generated near the positive electrode will react with the hydrogen generated at the negative electrode to generate water again, maintaining the stability of the internal pressure of the battery and the concentration of the sulfuric acid electrolyte. However, when overcharging or too high internal temperature occurs, the gas generated inside the battery will carry sulfuric acid mist and precipitate out through the vent valve together, resulting in water loss and electrolyte leakage of the battery, causing the performance aging of the battery monomer. Due to the differences among lead-acid battery monomers, when a certain lead-acid battery monomer shows performance aging prematurely, it will expand the inconsistency of the battery pack, leading to a reduction in the service life of the entire battery pack. Therefore, evaluating the aging degree of the battery and replacing abnormal batteries in a timely manner are the keys to ensuring the safe and stable operation of the battery pack.

[0003] In the related art, evaluating the aging degree of a battery is specifically manifested as: obtaining the circuit parameter information of each battery in the battery pack, and evaluating the aging degree of the battery based on the constructed adaptive algorithm model according to the circuit parameter information. However, the accuracy of the adaptive algorithm model depends on sample data, resulting in poor credibility of the evaluation result and being not conducive to online monitoring. Summary of the Invention

[0004] The battery aging degree evaluation method, system, device, and electronic device provided by the present application are used to achieve the effect of improving the accuracy of the evaluation result and being conducive to online monitoring.

[0005] In a first aspect, the present application provides a method for evaluating the aging degree of a battery, including:

[0006] After detecting that the battery voltage of a lead-acid battery monomer is less than a preset battery cut-off voltage, obtaining the target open-circuit voltage of the lead-acid battery monomer, where the target open-circuit voltage is determined according to the component mass in the gas precipitated from the vent valve of the lead-acid battery monomer;

[0007] Based on the preset correspondence between the state of charge and the open-circuit voltage, determining the target state of charge corresponding to the target open-circuit voltage according to the target open-circuit voltage;

[0008] According to the target state of charge and the rated capacity of the lead-acid battery monomer, determining the battery health state of the lead-acid battery monomer, where the battery health state reflects the aging degree of the battery.

[0009] In a possible implementation, the target open-circuit voltage is determined as follows:

[0010] Obtain the component mass in the gas evolved from the vent valve of the lead-acid battery cell, where the component mass includes the sulfuric acid mass and the water mass;

[0011] Determine the molar concentration of the sulfuric acid electrolyte of the lead-acid battery cell based on the sulfuric acid mass and the water mass;

[0012] Determine the target open-circuit voltage of the lead-acid battery cell based on the molar concentration.

[0013] In a possible implementation, the target open-circuit voltage satisfies the following formula:

[0014]

[0015] Wherein, represents the potential of the positive electrode of the lead-acid battery cell relative to the hydrogen electrode potential, represents the potential of the negative electrode of the lead-acid battery cell relative to the hydrogen electrode potential, T represents the absolute temperature of the environment, represents the molar concentration of the sulfuric acid electrolyte of the lead-acid battery cell, and EOCV represents the target open-circuit voltage.

[0016] In a possible implementation, according to the target state of charge and the rated capacity of the lead-acid battery cell, determine the state of health of the lead-acid battery cell, including:

[0017] Determine the remaining available capacity of the lead-acid battery cell according to the target state of charge and the rated capacity;

[0018] Determine the state of health of the lead-acid battery cell according to the remaining available capacity and the rated capacity.

[0019] In a possible implementation, the remaining available capacity of the lead-acid battery cell satisfies the following formula:

[0020]

[0021] Wherein, represents the rated capacity of the lead-acid battery cell, represents the target state of charge corresponding to the target open-circuit voltage in the fully discharged state of the lead-acid battery cell, represents the remaining available capacity of the lead-acid battery cell.

[0022] In a possible implementation, the method for evaluating the degree of battery aging further includes:

[0023] Visualize the state of health and / or state of charge of a lead-acid battery cell;

[0024] And / or, when the state of health of the battery is less than a preset state-of-health threshold of the battery, prompt abnormal information, where the abnormal information includes the identification information of the lead-acid battery cell and the state of health of the battery.

[0025] In a second aspect, the present application provides a device for evaluating the degree of battery aging, including:

[0026] An acquisition module, configured to obtain the target open-circuit voltage of the lead-acid battery cell after detecting that the battery voltage of the lead-acid battery cell is less than a preset battery cut-off voltage, where the target open-circuit voltage is determined according to the component mass in the gas evolved from the vent valve of the lead-acid battery cell;

[0027] A determination module, configured to determine the target state of charge corresponding to the target open-circuit voltage based on the preset correspondence between the state of charge and the open-circuit voltage, according to the target open-circuit voltage; and determine the state of health of the lead-acid battery cell according to the target state of charge and the rated capacity of the lead-acid battery cell, where the state of health of the battery reflects the degree of battery aging.

[0028] In a possible implementation manner, the target open-circuit voltage is determined by the following method:

[0029] Obtain the component mass in the gas evolved from the vent valve of the lead-acid battery cell, where the component mass includes the sulfuric acid mass and the moisture mass;

[0030] Determine the molar concentration of the sulfuric acid electrolyte of the lead-acid battery cell according to the sulfuric acid mass and the moisture mass;

[0031] Determine the target open-circuit voltage of the lead-acid battery cell according to the molar concentration.

[0032] In a possible implementation manner, the target open-circuit voltage satisfies the following formula:

[0033]

[0034] Wherein, represents the potential of the positive electrode of the lead-acid battery cell relative to the hydrogen electrode potential, represents the potential of the negative electrode of the lead-acid battery cell relative to the hydrogen electrode potential, T represents the absolute temperature of the environment, represents the molar concentration of the sulfuric acid electrolyte of the lead-acid battery cell, and EOCV represents the target open-circuit voltage.

[0035] In a possible implementation, the determination module is specifically configured to: determine the remaining available capacity of the lead-acid battery cell according to the target state of charge and the rated capacity; determine the battery health state of the lead-acid battery cell according to the remaining available capacity and the rated capacity.

[0036] In a possible implementation, the remaining available capacity of the lead-acid battery cell satisfies the following formula:

[0037]

[0038] Wherein, represents the rated capacity of the lead-acid battery cell, represents the target state of charge corresponding to the target open-circuit voltage of the lead-acid battery cell in the fully discharged state, represents the remaining available capacity of the lead-acid battery cell.

[0039] In a possible implementation, the battery aging degree evaluation device further includes a display module, and the display module is configured to: visually display the battery health state and / or the state of charge of the lead-acid battery cell; and / or, when the battery health state is less than a preset battery health state threshold, prompt abnormal information, and the abnormal information includes the identification information and the battery health state of the lead-acid battery cell.

[0040] In a third aspect, the present application provides an electronic device, including: a memory, a processor;

[0041] The memory stores computer execution instructions;

[0042] The processor executes the computer execution instructions stored in the memory, so that the processor executes the above first aspect and / or various possible implementations of the first aspect.

[0043] In a fourth aspect, the present application provides a battery aging degree evaluation system, including: a gas sensor and a signal processor, and the gas sensor and the signal processor are connected;

[0044] The gas sensor is configured to monitor the gas evolved from the overflow valve of the lead-acid battery cell, obtain the component mass in the gas, and transmit the component mass to the signal processor;

[0045] The signal processor is configured to process the received component mass based on the method according to any one of the first aspect to obtain the battery health state of the lead-acid battery cell, and the battery health state reflects the battery aging degree.

[0046] In a possible implementation, the battery aging degree evaluation system further includes: an analog-to-digital conversion device, and the analog-to-digital conversion device is respectively connected to the gas sensor and the signal processor;

[0047] A gas sensor, specifically used to monitor the gas evolved from the gas overflow valve of a lead-acid battery cell, obtain a component mass analog signal in the gas, and transmit the component mass analog signal to an analog-to-digital conversion device;

[0048] An analog-to-digital conversion device, configured to sequentially filter and amplify the received component content analog signal and then convert it into a component mass digital signal, and transmit the component mass digital signal to a signal processor;

[0049] A signal processor, configured to process the received component mass digital signal based on the method according to any one of the first aspect to obtain the battery health state of the lead-acid battery cell.

[0050] In a fifth aspect, the present application provides a computer-readable storage medium storing computer-executable instructions, which are used to implement the above first aspect and / or various possible implementation manners of the first aspect when executed.

[0051] In a sixth aspect, the present application provides a computer program product including a computer program, which implements the above first aspect and / or various possible implementation manners of the first aspect when executed by a processor.

[0052] The battery aging degree evaluation method, system, device and electronic device provided by the present application, after monitoring that the battery voltage of the lead-acid battery cell is less than a preset battery cut-off voltage, obtain the target open-circuit voltage of the lead-acid battery cell, where the target open-circuit voltage is determined according to the component mass in the gas evolved from the gas overflow valve of the lead-acid battery cell; based on the preset correspondence between the state of charge and the open-circuit voltage, determine the target state of charge corresponding to the target open-circuit voltage; according to the target state of charge and the rated capacity of the lead-acid battery cell, determine the battery health state of the lead-acid battery cell, and the battery health state reflects the battery aging degree. In the present application, the open-circuit voltage of the lead-acid battery cell is determined by the component mass in the gas evolved from the gas overflow valve, improving the accuracy of the open-circuit voltage. After monitoring that the battery voltage of the lead-acid battery cell is less than the preset battery cut-off voltage, the correspondence between the open-circuit voltage and the state of charge is applied to evaluate the aging degree of the lead-acid battery cell, improving the accuracy of the evaluation result and facilitating on-line monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The accompanying drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present application and used together with the specification to explain the principles of the present application.

[0054] Figure 1 It is a schematic structural diagram of a valve-regulated lead-acid battery cell;

[0055] Figure 2 It is a flowchart of the battery aging degree evaluation method provided by the present applicationFigure 1 ;

[0056] Figure 3 Schematic flow of the battery aging degree evaluation method provided by this application Figure 2 ;

[0057] Figure 4 Schematic structure of the battery aging degree evaluation system provided by this application Figure 1 ;

[0058] Figure 5 Schematic structure of the battery aging degree evaluation system provided by this application Figure 2 ;

[0059] Figure 6 Schematic diagram of the structure of the battery aging degree evaluation device provided by this application;

[0060] Figure 7 Schematic diagram of the structure of the electronic device provided by this application.

[0061] Through the above-mentioned drawings, specific embodiments of this application have been shown, and there will be more detailed descriptions hereinafter. These drawings and textual descriptions are not intended to limit the scope of the concept of this application in any way, but to illustrate the concept of this application to those skilled in the art by referring to specific embodiments. Detailed Description of the Invention

[0062] Here, the exemplary embodiments will be described in detail, and the examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. On the contrary, they are merely examples of devices and methods consistent with some aspects of this application as detailed in the appended claims.

[0063] The DC power supply system of a substation is generally composed of 52 or 104 lead-acid battery monomers, such as valve-regulated lead-acid battery monomers, connected in series to provide stable 110V or 220V DC power supply for the secondary equipment of the substation. The structure of its monomer is as Figure 1 shown, Figure 1 Schematic diagram of the structure of a valve-regulated lead-acid battery monomer, including a negative electrode, a positive electrode, and a gas overflow valve.

[0064] The valve-regulated lead-acid battery generates a chemical reaction through the active substances at the positive and negative electrodes, conducts ions through the sulfuric acid electrolyte, and forms a closed loop with the external circuit to provide electrical energy for the external circuit. The chemical reaction during its charging is as follows:

[0065]

[0066] In the later stage of lead-acid battery charging, since the chemical reactions of the active substances inside the battery are basically completed, the excess electricity causes a side reaction of electrolyzing water in the battery, generating hydrogen and oxygen at the two poles of the battery respectively. However, when overcharging or internal temperature is too high occurs, the gas generated inside the battery will carry sulfuric acid mist and precipitate out through the air vent valve together, resulting in water loss and electrolyte leakage of the battery, and causing the performance aging of the battery monomer. In practical applications, the gas evolution phenomenon of the air vent valve may occur at any moment during the charging or discharging process of the lead-acid battery. Therefore, it is crucial to timely evaluate the aging degree of the battery.

[0067] In the related art, by obtaining the circuit parameter information of the battery and building a corresponding adaptive algorithm model, the evaluation of the battery aging state is realized, without the need to consume labor costs for testing. However, this method requires a significant increase in the complexity of calculation and the amount of data storage. The calculation accuracy depends on the sample data, and the credibility of the calculation result is poor, which is not conducive to on-line monitoring.

[0068] Aiming at the above technical problems, the present application provides a method for evaluating the aging degree of a battery. By determining the open-circuit voltage based on the component mass in the gas evolved from the air vent valve of the lead-acid battery monomer, the accuracy of the open-circuit voltage is improved. By applying the correlation between the open-circuit voltage and the state of charge, the state of charge of the lead-acid battery monomer when the battery is fully discharged is determined, and then the aging degree of the lead-acid battery monomer is evaluated, improving the accuracy of the evaluation result and being conducive to on-line monitoring.

[0069] The following takes specific embodiments to elaborate in detail on the technical solutions of the present application and how the technical solutions of the present application solve the above technical problems. These several specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the drawings.

[0070] Figure 2 The flow chart of the method for evaluating the aging degree of the battery provided by the present application Figure 1 As Figure 2 shown, the method includes:

[0071] S201. After monitoring that the battery voltage of the lead-acid battery monomer is less than the preset battery cut-off voltage, obtain the target open-circuit voltage of the lead-acid battery monomer, where the target open-circuit voltage is determined according to the component mass in the gas evolved from the air vent valve of the lead-acid battery monomer.

[0072] Among them, the open-circuit voltage reflects the content of the remaining active substances inside the lead-acid battery monomer and is less affected by external factors. The content of the remaining active substances inside is associated with the gas evolved from the air vent valve. By analyzing the component mass in the gas evolved from the air vent valve, the determination of the open-circuit voltage can be realized.

[0073] During the charge and discharge cycle of a lead-acid battery cell, when the electricity stored in the lead-acid battery cell is completely released, the open circuit voltage at this time can be called the open circuit voltage in the fully discharged state, that is, the target open circuit voltage. Studying the performance of lead-acid battery cells in the fully discharged state can more accurately reflect the degree of battery aging.

[0074] When the battery voltage of the lead-acid battery cell is lower than the preset battery cut-off voltage, it can be regarded that the battery begins to enter the full discharge state.

[0075] For example, a battery inspection meter is used to monitor the battery voltage. Assuming that the normal operating voltage range of a lead-acid battery cell is 1.8V~2.35V, the battery cut-off voltage is 1.8V. As the battery is continuously discharged, its battery voltage decreases accordingly. When the battery voltage is monitored to be less than 1.8V, it is determined that the battery begins to enter a full discharge state, and the target open circuit voltage of the lead-acid battery cell is obtained.

[0076] It should be noted that the open circuit voltage is determined in real time based on the mass of the components in the gas released from the overflow valve of the lead-acid battery cell, and the timing for obtaining the target open circuit voltage starts from the time when the battery enters the fully discharged state.

[0077] S202 : Based on a preset correspondence between the state of charge and the open circuit voltage, and according to the target open circuit voltage, determine a target state of charge corresponding to the target open circuit voltage.

[0078] The open circuit voltage (OCV) of a battery can be used as an indicator to estimate the state of charge (SOC). Usually, there is a certain correspondence between the open circuit voltage and the state of charge, which can be measured by a staged discharge test method to obtain the correspondence between the state of charge and the open circuit voltage.

[0079] The corresponding relationship between SOC and OCV of lead-acid battery cells of different models or materials is different. For example, a new lead-acid battery cell of the same model is subjected to standard charging to ensure that the battery is fully charged to a SOC of 100%. After standing for 24 hours, intermittent discharge is started. For example, each time the SOC is discharged by 5%, the open circuit voltage is measured after standing for 24 hours until the SOC is 0. Finally, data fitting is performed based on the multiple sets of measured data to obtain the corresponding relationship between the charge state and the open circuit voltage.

[0080] The corresponding relationship between the state of charge and the open circuit voltage can be expressed in the form of a fitting function, a fitting curve, a data pair, etc. For example, after obtaining the target open circuit voltage, the target state of charge corresponding to the target open circuit voltage is obtained by indexing in multiple data pairs according to the target open circuit voltage. Alternatively, the target open circuit voltage is substituted into the fitting function or the fitting curve to obtain the target state of charge corresponding to the target open circuit voltage.

[0081] S203. Determine the state of health of the lead-acid battery cell according to the target state of charge and the rated capacity of the lead-acid battery cell. The state of health of the battery reflects the degree of battery aging.

[0082] The larger the state of health (SOH) of the battery, the smaller the degree of battery aging. Conversely, the smaller the SOH, the greater the degree of battery aging.

[0083] The state of health of the battery is related to the available capacity of the battery and the rated capacity at the time of factory. The available capacity of the battery is affected by the available charge. Given that the definition of the state of charge is the ratio of the available charge to the available capacity, the state of health of the lead-acid battery cell can be determined according to the target state of charge and the rated capacity of the lead-acid battery cell.

[0084] In the embodiments of the present application, the open circuit voltage is determined by using the component mass in the gas evolved from the vent valve of the lead-acid battery cell, which improves the accuracy of the open circuit voltage. By applying the correlation between the open circuit voltage and the state of charge, the target state of charge of the lead-acid battery cell when the battery is fully discharged is determined, and then the degree of aging of the lead-acid battery cell is evaluated. Compared with calculating the SOH by using the battery internal resistance and machine learning, there are problems such as large error and strong sample dependence. The embodiments of the present application improve the accuracy of the evaluation result and are conducive to online monitoring. Compared with obtaining the battery state information through time-consuming and laborious capacity verification and discharge testing, the embodiments of the present application save labor costs.

[0085] In addition, the embodiments of the present application improve the estimation accuracy of the battery aging degree without any algorithm optimization and data optimization, have good engineering application value, effectively improve the monitoring effect of the lead-acid battery, and have the ability to assist decision-making for the evaluation and prediction of battery performance.

[0086] In some embodiments, the target open circuit voltage is determined in the following manner: Obtain the component mass in the gas evolved from the vent valve of the lead-acid battery cell, where the component mass includes the sulfuric acid mass and the moisture mass; Determine the molar concentration of the sulfuric acid electrolyte of the lead-acid battery cell according to the sulfuric acid mass and the moisture mass; Determine the target open circuit voltage of the lead-acid battery cell according to the molar concentration.

[0087] During the use of the lead-acid battery cell, when overcharging or the internal temperature is too high occurs, the gas generated inside the battery will carry sulfuric acid mist and evolve through the vent valve together. For example, a gas sensor is arranged at the vent valve of the lead-acid battery cell, the component mass in the gas evolved from the vent valve is collected through the gas sensor, and then the component mass in the gas evolved from the vent valve is obtained in real time from the gas sensor for calculating the molar concentration of the sulfuric acid electrolyte.

[0088] Calculate the molar concentration of the sulfuric acid electrolyte of a single lead - acid battery cell based on the definition formula of molar concentration.

[0089]

[0090] Among them, is the mass of precipitated sulfuric acid, is the mass of precipitated water, is the mass of the initial sulfuric acid electrolyte of the battery, is the volume of the initial sulfuric acid electrolyte of the battery, is the density of water under standard conditions, is the density of sulfuric acid under standard conditions, is the relative molecular mass of sulfuric acid.

[0091] It can be understood that the volume and mass of the initial sulfuric acid electrolyte of the battery can be provided at the time of factory. In the embodiments of the present application, only the component masses ( and ) in the gas precipitated from the vent valve need to be obtained and substituted into the formula.

[0092] In addition, and are both the cumulative component masses precipitated from the vent valve at the moment of obtaining the target open - circuit voltage up to the current time.

[0093] The molar concentration of the sulfuric acid electrolyte can determine the target open - circuit voltage of a single lead - acid battery cell. As the battery discharges, the molar concentration decreases.

[0094] In the embodiments of the present application, by obtaining the component masses in the gas precipitated from the vent valve in real time to determine the molar concentration of the sulfuric acid electrolyte of a single lead - acid battery cell, the molar concentration can truly reflect the concentration of the active substances inside the battery, and the target open - circuit voltage of the single lead - acid battery cell is determined using the molar concentration, improving the accuracy of the open - circuit voltage.

[0095] Furthermore, in some embodiments, the target open - circuit voltage satisfies the following formula:

[0096]

[0097] Among them, represents the potential of the positive electrode of a single lead - acid battery cell relative to the hydrogen electrode, represents the potential of the negative electrode of a single lead - acid battery cell relative to the hydrogen electrode, T represents the absolute temperature of the environment, represents the molar concentration of the sulfuric acid electrolyte of a single lead - acid battery cell, and EOCV represents the target open - circuit voltage.

[0098] It should be noted that, and is a fixed value determined by the battery material. T represents the absolute temperature of the environment where the lead-acid battery cell is located in the nuclear power plant.

[0099] In some embodiments, according to the target state of charge and the rated capacity of the lead-acid battery cell, the battery health state of the lead-acid battery cell is determined, including: determining the remaining available capacity of the lead-acid battery cell according to the target state of charge and the rated capacity; determining the battery health state of the lead-acid battery cell according to the remaining available capacity and the rated capacity.

[0100] It can be understood that as the battery performance decays, the target open-circuit voltage under the full discharge state of the battery gradually rises, the storable electricity gradually decreases, and the corresponding available capacity also gradually decreases. For example, for a brand-new battery or an unaged battery, the SOC is 100% when fully charged, and the SOC is 0 after full discharge; for an aged battery, the SOC may still be greater than 0 after full discharge, and this part of the SOC belongs to invalid electricity, resulting in a decrease in the storable electricity. As the battery ages, the invalid electricity will gradually increase.

[0101] Further, the remaining available capacity of the lead-acid battery cell is expressed as , and the remaining available capacity of the lead-acid battery cell satisfies the following formula:

[0102]

[0103] Among them, represents the rated capacity of the lead-acid battery cell, represents the target state of charge corresponding to the target open-circuit voltage under the full discharge state of the lead-acid battery cell.

[0104] It can be seen from the definition of SOH that SOH is the ratio of the remaining available capacity to the rated capacity, that is:

[0105]

[0106] To facilitate relevant personnel to grasp the health state of the lead-acid battery cell in real time, optionally, in some embodiments, the battery aging degree evaluation method may further include: visually displaying the battery health state and / or the state of charge of the lead-acid battery cell; and / or, when the battery health state is less than a preset battery health state threshold, prompting abnormal information, where the abnormal information includes the identification information and the battery health state of the lead-acid battery cell.

[0107] One implementation method is to visually display the battery health state and / or the state of charge of the lead-acid battery cell.

[0108] Exemplarily, through a visual large screen, at least one of the battery health state and the state of charge is monitored and displayed in real time.

[0109] In another implementation, when the state of health of the battery is less than a preset state-of-health threshold of the battery, a prompt for abnormal information is given.

[0110] Exemplarily, the state-of-health threshold of the battery is 80%. When the SOH is less than 80%, it indicates that the lead-acid battery cell is aged and fails. The identification information of the aged and failed lead-acid battery cell, such as the number, and the SOH are displayed through a visualization large screen or other means. Optionally, voice alarms, information notifications, and other methods can also be provided to remind the user to pay attention to the abnormality. When the SOH is greater than or equal to 80%, it indicates that the lead-acid battery cell has not aged and failed, and then the state of health of the lead-acid battery cell continues to be monitored.

[0111] Optionally, the open-circuit voltage can also be visually displayed.

[0112] In one implementation, the state of health and / or state of charge of the lead-acid battery cell is visually displayed, and when the state of health of the battery is less than a preset state-of-health threshold of the battery, a prompt for abnormal information is given.

[0113] In the embodiments of the present application, through visual display, the user can monitor the SOC and SOH of the battery in real time, helping the user to timely understand the current state and performance of the battery. Through timely prompt of abnormal information, the user can quickly identify and handle potential battery failures, reduce safety risks, and have the warning ability to detect and handle early the battery that is abnormally gassing, losing water, and aging and failing. It effectively prevents the occurrence of potential faults in the DC system caused by the deterioration of the battery pack.

[0114] Figure 3 Schematic flow of the battery aging degree evaluation method provided by the present application Figure 2 , as Figure 3 shown. Based on the above embodiments, a specific embodiment is used to illustrate the battery aging degree evaluation method. The battery aging degree evaluation method includes:

[0115] S301. Initialize the rated capacity, open-circuit voltage at full charge state, open-circuit voltage at full discharge state, current SOC, and SOH parameters of the individual battery cells in the battery pack.

[0116] The individual battery cells in the battery pack are the lead-acid battery cells described in the above embodiments.

[0117] The open-circuit voltage at full discharge state is the target open-circuit voltage described in the above embodiments.

[0118] S302. Obtain the component mass in the gas evolved from the gas overflow valve of each individual battery cell in the battery pack.

[0119] For example, obtain the component mass in the gas evolved from the vent valve of a lead-acid battery cell from a gas sensor.

[0120] S303. Calculate the remaining active material content data of the battery body using the gas evolution data.

[0121] Based on the gas evolution data (the sulfuric acid mass and water mass included in the component mass of the gas evolved from the vent valve), determine the molar concentration of the sulfuric acid electrolyte of the lead-acid battery cell.

[0122] The remaining active material content data is the molar concentration of the sulfuric acid electrolyte.

[0123] S304. Use the remaining active material content data to determine parameters such as the OCV and SOC of the battery.

[0124] Based on the molar concentration, the open circuit voltage (and the target open circuit voltage) of the lead-acid battery cell can be determined. Then, based on the preset correspondence between the state of charge and the open circuit voltage, the state of charge corresponding to the open circuit voltage can be determined.

[0125] S305. Calculate the SOH parameter of the battery using the measured OCV and SOC data.

[0126] After the lead-acid battery cell is in the fully discharged state, the open circuit voltage at this time is the target open circuit voltage EOCV. Obtain the target open circuit voltage. Based on the preset correspondence between the state of charge and the open circuit voltage, the target state of charge corresponding to the target open circuit voltage can be determined. 。

[0127]

[0128] Then calculate the SOH through this formula.

[0129] S306. Display the SOC and SOH parameters of all single battery cells.

[0130] Visualize the battery health state and / or the state of charge of the lead-acid battery cell.

[0131] S306. Determine whether the SOH is less than 80%.

[0132] Judge whether the battery health state is less than the preset battery health state threshold.

[0133] S307. Display the numbers of the single battery cells with SOH exceeding the limit and their SOH parameters.

[0134] When the battery health state is less than the preset battery health state threshold, give a prompt for abnormal information. The abnormal information includes the identification information and the battery health state of the lead-acid battery cell. For example, the identification information is the battery number.

[0135] In summary, the present application has at least the following advantages:

[0136] 1. By determining the open-circuit voltage using the component mass in the gas evolved from the vent valve of a lead-acid battery cell, the accuracy of the open-circuit voltage is improved. Applying the correlation between the open-circuit voltage and the state of charge, the target state of charge of the lead-acid battery cell when the battery is fully discharged is determined, and then the aging degree of the lead-acid battery cell is evaluated. Compared with using battery internal resistance and machine learning to calculate SOH, there are problems such as large errors and strong sample dependence. The present application improves the accuracy of the evaluation results and is conducive to online monitoring. Compared with obtaining the battery state information through time-consuming and laborious capacity discharge tests, the present application saves labor costs.

[0137] 2. Without applying any algorithm optimization and data optimization, the present application improves the estimation accuracy of the battery aging degree, has good engineering application value, effectively improves the monitoring effect of lead-acid batteries, and has the ability to assist in decision-making for the evaluation and prediction of battery performance.

[0138] 3. Through visual display, users can monitor the SOC and SOH of the battery in real time, helping users to understand the current state and performance of the battery in a timely manner. Through timely abnormal information prompts, users can quickly identify and handle potential battery failures, reduce safety risks, and have the ability to detect and handle early the aging and failure of batteries due to abnormal gas evolution and water loss. It effectively prevents the occurrence of potential faults in the DC system caused by the deterioration of the battery pack.

[0139] Figure 4 For the structural schematic of the battery aging degree evaluation system provided by the present application Figure 1 , as Figure 4 shown, the battery aging degree evaluation system 40 provided in this embodiment includes: a gas sensor 41 and a signal processor 42, and the gas sensor 41 and the signal processor 42 are connected;

[0140] The gas sensor 41 is used to monitor the gas evolved from the vent valve of the lead-acid battery cell, obtain the component mass in the gas, and transmit the component mass to the signal processor 42;

[0141] The signal processor 42 is used to process the received component mass based on the battery aging degree evaluation method in the above embodiment to obtain the battery health state of the lead-acid battery cell, and the battery health state reflects the battery aging degree.

[0142] In a possible implementation manner, as Figure 5 For the structural schematic of the battery aging degree evaluation system provided by the present application Figure 2 shown, the battery aging degree evaluation system 40 further includes: an analog-to-digital conversion device 43, and the analog-to-digital conversion device 43 is respectively connected to the gas sensor 41 and the signal processor 42;

[0143] A gas sensor 41, specifically used for monitoring the gas evolved from the vent valve of a lead-acid battery cell, obtaining a component mass analog signal in the gas, and transmitting the component mass analog signal to an analog-to-digital conversion device 43;

[0144] The analog-to-digital conversion device 43 is used to sequentially filter and amplify the received component content analog signal and then convert it into a component mass digital signal, and transmit the component mass digital signal to a signal processor 42;

[0145] The signal processor 42 is used to process the received component mass digital signal based on the battery aging degree evaluation method in the above embodiments to obtain the battery health state of the lead-acid battery cell.

[0146] The following is an embodiment of the device of the present application, which can be used to execute the embodiment of the method of the present application. For details not disclosed in the embodiment of the device of the present application, please refer to the embodiment of the method of the present application.

[0147] Figure 6 It is a schematic structural diagram of the battery aging degree evaluation device provided by the present application, as Figure 6 shown, the battery aging degree evaluation device 60 provided in this embodiment includes: an acquisition module 61 and a determination module 62. Among them:

[0148] The acquisition module 61 is used to obtain the target open-circuit voltage of the lead-acid battery cell after monitoring that the battery voltage of the lead-acid battery cell is less than the preset battery cut-off voltage, and the target open-circuit voltage is determined according to the component mass in the gas evolved from the vent valve of the lead-acid battery cell;

[0149] The determination module 62 is used to determine the target state of charge corresponding to the target open-circuit voltage based on the pre-set correspondence between the state of charge and the open-circuit voltage, according to the target open-circuit voltage; and, determine the battery health state of the lead-acid battery cell according to the target state of charge and the rated capacity of the lead-acid battery cell, and the battery health state reflects the degree of battery aging.

[0150] In a possible implementation manner, the target open-circuit voltage is determined by the following method:

[0151] Obtain the component mass in the gas evolved from the vent valve of the lead-acid battery cell, and the component mass includes the sulfuric acid mass and the moisture mass;

[0152] Determine the molar concentration of the sulfuric acid electrolyte of the lead-acid battery cell according to the sulfuric acid mass and the moisture mass;

[0153] Determine the target open-circuit voltage of the lead-acid battery cell according to the molar concentration.

[0154] In a possible implementation manner, the target open-circuit voltage satisfies the following formula:

[0155]

[0156] Among them, represents the relative hydrogen electrode potential of the positive electrode of the lead-acid battery cell, represents the relative hydrogen electrode potential of the negative electrode of the lead-acid battery cell, T represents the absolute temperature of the environment, represents the molar concentration of the sulfuric acid electrolyte of the lead-acid battery cell, and EOCV represents the target open-circuit voltage.

[0157] In a possible implementation manner, the determining module 62 is specifically configured to: determine the remaining available capacity of the lead-acid battery cell according to the target state of charge and the rated capacity; determine the state of health of the lead-acid battery cell according to the remaining available capacity and the rated capacity.

[0158] In a possible implementation manner, the remaining available capacity of the lead-acid battery cell satisfies the following formula:

[0159]

[0160] Among them, represents the rated capacity of the lead-acid battery cell, represents the target state of charge corresponding to the target open-circuit voltage in the fully discharged state of the lead-acid battery cell, represents the remaining available capacity of the lead-acid battery cell.

[0161] In a possible implementation manner, the battery aging degree evaluation device further includes a display module, and the display module is configured to: visually display the state of health and / or the state of charge of the lead-acid battery cell; and / or, when the state of health is less than a preset state of health threshold, prompt abnormal information, and the abnormal information includes the identification information and the state of health of the lead-acid battery cell.

[0162] The battery aging degree evaluation device provided in this embodiment can execute the method provided in the above method embodiment, and its implementation principle and technical effects are similar, and will not be elaborated here in this embodiment.

[0163] Figure 7 is a schematic structural diagram of the electronic device provided in this application. As Figure 7 shown, the electronic device 70 provided in this embodiment includes: at least one processor 701 and a memory 702. Optionally, the device 70 further includes a communication component 703. Among them, the processor 701, the memory 702, and the communication component 703 are connected through a bus 704.

[0164] In a specific implementation process, at least one processor 701 executes computer-executable instructions stored in a memory 702, so that at least one processor 701 executes the above-mentioned method.

[0165] For the specific implementation process of the processor 701, reference may be made to the above method embodiment. The implementation principle and technical effect are similar, and will not be elaborated here in this embodiment.

[0166] In the above embodiment, it should be understood that the processor may be a central processing unit (Central Processing Unit, CPU for short), or other general-purpose processors, digital signal processors (Digital Signal Processor, DSP for short), application specific integrated circuits (Application Specific Integrated Circuit, ASIC for short), etc. The general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the method disclosed in combination with the invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules in the processor.

[0167] The memory may include a high-speed memory (Random Access Memory, RAM), and may also include a non-volatile memory (Non-volatile Memory, NVM), such as at least one disk memory.

[0168] The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, the bus in the drawings of this application is not limited to only one bus or one type of bus.

[0169] This application also provides a computer program product, including a computer program, which implements the above method when executed by a processor.

[0170] This application also provides a computer-readable storage medium, in which computer-executable instructions are stored, and when the processor executes the computer-executable instructions, the above method is implemented.

[0171] The above-readable storage medium may be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, a magnetic disk, or an optical disk. The readable storage medium may be any available medium accessible by a general-purpose or special-purpose computer.

[0172] An exemplary readable storage medium is coupled to the processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium may also be an integral part of the processor. The processor and the readable storage medium may be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium may also exist as discrete components in a device.

[0173] The division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other may be indirect couplings or communication connections through some interfaces, devices, or units, and may be in electrical, mechanical, or other forms.

[0174] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0175] In addition, in each embodiment of the present invention, the functional units may be integrated in a processing unit, may exist separately as individual physical units, or two or more units may be integrated in one unit.

[0176] If a function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes: USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs, and other various media that can store program codes.

[0177] Those of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When this program is executed, it executes the steps including the above method embodiments; and the aforementioned storage medium includes: ROMs, RAMs, magnetic disks, or optical discs, and other various media that can store program codes.

[0178] Finally, it should be noted that: After considering the specification and practicing the invention disclosed herein, those skilled in the art will easily think of other implementation manners of the present invention. The present invention is intended to cover any variations, uses, or adaptive changes of the present invention. These variations, uses, or adaptive changes follow the general principles of the present invention and include common general knowledge or conventional technical means in the technical field not disclosed in the present invention. It is not limited to the exact structure already described and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present invention is only limited by the appended claims.

Claims

1. A method for evaluating battery aging, characterized in that: include: After monitoring that the battery voltage of the lead-acid battery cell is less than a preset battery cut-off voltage, obtaining a target open circuit voltage of the lead-acid battery cell, wherein the target open circuit voltage is determined according to the mass of the components in the gas released from the overflow valve of the lead-acid battery cell; Based on a preset correspondence relationship between the state of charge and the open circuit voltage, and according to the target open circuit voltage, determining a target state of charge corresponding to the target open circuit voltage; The battery health state of the lead-acid battery cell is determined according to the target state of charge and the rated capacity of the lead-acid battery cell, and the battery health state reflects the degree of battery aging.

2. The battery aging evaluation method according to claim 1, characterized in that: The target open circuit voltage is determined by: Obtaining the mass of components in the gas released by the overflow valve of the lead-acid battery cell, wherein the mass of the components includes the mass of sulfuric acid and the mass of water; Determining the molar concentration of the sulfuric acid electrolyte of the lead-acid battery monomer according to the mass of the sulfuric acid and the mass of the water; The target open circuit voltage of the lead-acid battery cell is determined according to the molar concentration.

3. The battery aging evaluation method according to claim 2, characterized in that: The target open circuit voltage satisfies the following formula: in, Indicates the potential of the positive electrode of a lead-acid battery relative to the hydrogen electrode. represents the potential of the negative electrode of the lead-acid battery relative to the hydrogen electrode, T represents the absolute temperature of the environment, It represents the molar concentration of sulfuric acid electrolyte in the lead-acid battery monomer, and EOCV represents the target open circuit voltage.

4. The battery aging degree assessment method according to any one of claims 1 to 3, characterized in that: The step of determining the battery health state of the lead-acid battery cell according to the target state of charge and the rated capacity of the lead-acid battery cell comprises: Determining the remaining available capacity of the lead-acid battery cell according to the target state of charge and the rated capacity; The battery health state of the lead-acid battery cell is determined according to the remaining available capacity and the rated capacity.

5. The battery aging evaluation method according to claim 4, characterized in that: The remaining available capacity of the lead-acid battery monomer satisfies the following formula: in, Indicates the rated capacity of a lead-acid battery cell. Indicates the target state of charge corresponding to the target open circuit voltage of the lead-acid battery cell when it is fully discharged. Indicates the remaining available capacity of a lead-acid battery cell.

6. The battery aging degree assessment method according to any one of claims 1 to 3, characterized in that: Also includes: Visually displaying the battery health status and / or charge status of the lead-acid battery cells; And / or, when the battery health status is less than a preset battery health status threshold, an abnormal information prompt is given, and the abnormal information includes identification information and battery health status of the lead-acid battery cell.

7. A battery aging evaluation device, characterized in that: include: An acquisition module, for acquiring a target open circuit voltage of a lead-acid battery cell after monitoring that the battery voltage of the lead-acid battery cell is less than a preset battery cut-off voltage, wherein the target open circuit voltage is determined according to the mass of components in the gas released by the overflow valve of the lead-acid battery cell; a determination module, configured to determine a target state of charge corresponding to the target open circuit voltage based on a preset correspondence relationship between the state of charge and the open circuit voltage and according to the target open circuit voltage; And, according to the target state of charge and the rated capacity of the lead-acid battery cell, the battery health state of the lead-acid battery cell is determined, and the battery health state reflects the degree of battery aging.

8. An electronic device, characterized in that: include: Memory, processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory, so that the processor performs the method according to any one of claims 1 to 6.

9. A battery aging assessment system, characterized in that: include: A gas sensor and a signal processor, wherein the gas sensor and the signal processor are connected; The gas sensor is used to monitor the gas released from the overflow valve of the lead-acid battery monomer, obtain the mass of the components in the gas, and transmit the mass of the components to the signal processor; The signal processor is used to process the received component mass based on the method according to any one of claims 1 to 6 to obtain the battery health status of the lead-acid battery cell, and the battery health status reflects the degree of battery aging.

10. The battery aging evaluation system according to claim 9, characterized in that: Also includes: an analog-to-digital conversion device, the analog-to-digital conversion device being connected to the gas sensor and the signal processor respectively; The gas sensor is specifically used to monitor the gas released from the overflow valve of the lead-acid battery cell, obtain the mass analog signal of the components in the gas, and transmit the mass analog signal of the components to the analog-to-digital conversion device; The analog-to-digital conversion device is used to sequentially filter and amplify the received component content analog signal and convert it into a component mass digital signal, and transmit the component mass digital signal to the signal processor; The signal processor is used to process the received component quality digital signal based on the method according to any one of claims 1 to 6 to obtain the battery health status of the lead-acid battery cell.

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