Failure processing method and system for series battery pack in storage battery power supply

Abstract

The invention relates to a series battery pack failure processing method and system in a storage battery power supply, and the method comprises the steps: carrying out the periodic detection of the internal resistance of each cell in a battery pack through a DC discharge method, and recognizing a fault cell; and after the fault battery cell is confirmed, the storage battery management system controls the relay to disconnect the fault battery cell, and the standby battery cell is connected to the battery pack. And after the standby battery cell is put into use, the storage battery management system performs performance test on the internal resistance of the battery cells in the battery pack so as to confirm whether each battery cell in the battery pack meets the use requirement or not. According to the invention, the internal resistance of each battery cell in the battery pack is periodically detected during self-maintenance of the battery, so that the fault battery cell is identified. For the battery cells with abnormal internal resistance and influence on normal work of the battery pack, the system automatically bypasses the fault battery cell by using the standby battery cell, so that the problem that the performance of the whole lithium battery pack is reduced due to poor health degree of individual battery cells of the battery pack in the mining high-reliability storage battery power supply is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery failure processing, and in particular to a method and system for processing failure of a series-connected battery pack in a battery power source. Background Art

[0002] In the field of mining battery power, battery packs are widely used due to their high energy density, long cycle life, etc. However, when the battery pack is used in series, if a single cell has a sudden change in internal resistance, it will often cause the performance of the entire battery pack to decline or even fail, seriously affecting the normal operation of mining equipment.

[0003] In the prior art, several types of processing methods for battery cell failures in battery packs and their defects are as follows: 1. Fault isolation method is used to isolate the battery cell with increased internal resistance. However, this method is only applicable to a series battery pack system with multiple batteries connected in parallel and then in series, and is not suitable for a battery pack with a single battery cell directly connected in series. 2. Active or passive balancing methods are used to balance the battery so that the terminal voltage of the individual battery cell is kept within a reasonable range. However, since the change in the internal resistance of the battery is a physical failure, relying on balancing to reduce the terminal voltage of the individual battery cell can only reduce the failure risk caused by the increase in the internal resistance of the battery cell to a certain extent, and cannot fundamentally solve the problem of battery pack failure caused by a single battery cell. 3. Consistency screening, when assembling the battery pack, a series of methods are used to screen the battery cells with consistent internal resistance, capacity and performance to assemble the battery pack. However, due to differences in the battery cell canning process, material consistency, use environment, and selection method, the battery cells change during use, which will lead to different electrochemical properties between the batteries, and the decay rate of the electrochemical performance of individual batteries increases exponentially. The internal resistance of the battery cell increases rapidly, resulting in a decrease in battery pack performance and a significant shortening of the battery pack life. In summary, although the existing technology can increase the service life of the battery pack to a certain extent, it cannot fundamentally solve the problem of battery pack failure caused by increased internal resistance of the battery cell. Summary of the invention

[0004] In view of this, it is necessary to provide a method and system for handling failure of series-connected battery packs in a battery power source to solve the above-mentioned defects of the prior art.

[0005] In order to solve the above problems, in a first aspect, an embodiment of the present invention provides a method for handling failure of a series-connected battery pack in a battery power source, comprising:

[0006] Step S1, periodically testing the internal resistance of each battery cell in the battery pack by a direct current discharge method to identify the faulty battery cell;

[0007] Step S2, after confirming the faulty battery cell, the battery management system controls the relay to disconnect the faulty battery cell and connect the spare battery cell to the battery pack.

[0008] Preferably, the method further comprises:

[0009] Step S3, after the spare battery cells are put into use, the battery management system performs a performance test on the internal resistance of the battery cells in the battery pack to confirm whether each battery cell in the battery pack meets the use requirements.

[0010] Preferably, in step S1, the step of periodically detecting the internal resistance of each battery cell in the battery pack by a DC discharge method to identify the faulty battery cell specifically includes:

[0011] S11, measuring the terminal voltage V1 of each battery cell in the no-load state of the battery pack;

[0012] S12, turn on the constant current electronic load, discharge the battery pack with a given constant current I, and continuously detect the cell terminal voltage until it stabilizes;

[0013] S13, after confirming that the cell terminal voltage is stable, record the cell voltage value V2 and collect the temperature of each cell;

[0014] S14, after determining that the temperature of each battery cell is stable according to the preset conditions, determining that the battery cell voltage value is valid;

[0015] S15, calculating the internal resistance of each battery cell according to the initial voltage V1 in the no-load state, the voltage value V2 after the battery cell terminal voltage is stabilized, and the applied constant current I;

[0016] S16, when the internal resistance of the battery cell exceeds the preset internal resistance threshold, return to steps S12 to S15 to perform a second measurement on the internal resistance of the battery cell. If the internal resistance of the battery cell still exceeds the preset internal resistance threshold after the second measurement, it is determined to be a faulty battery cell.

[0017] Preferably, in step S2, after confirming the faulty battery cell, the battery management system controls the relay to disconnect the faulty battery cell and connects the spare battery cell to the battery pack, which specifically includes:

[0018] S21, when the battery management system confirms the faulty cell, the system controls the single-pole single-throw relay to disconnect the faulty cell; wherein each cell is connected to a single-pole single-throw relay, and the single-pole single-throw relay is closed in the initial state;

[0019] The spare battery cell is connected to one contact of a single-pole double-throw relay, and the other contact of the single-pole double-throw relay is connected to the series circuit of the battery pack;

[0020] S22, the battery management system connects the disconnected fault line with the spare battery cell through the single-pole double-throw relay, and connects the spare battery cell to the battery pack;

[0021] Among them, the battery management system adopts a mutually exclusive signal method to control the single-pole single-throw relay and the single-pole double-throw relay respectively to ensure that the two relays are not closed at the same time.

[0022] Preferably, in step S3, after the spare battery cell is put into use, the battery management system performs a performance test on the internal resistance of the battery cell in the battery pack to confirm whether each battery cell in the battery pack meets the use requirements, specifically including:

[0023] S31, after the spare battery cell is put into use, the battery management system detects the internal resistance of the battery cell in the battery pack to determine whether the internal resistance is less than a preset internal resistance threshold; wherein the preset internal resistance threshold = the initial value of the battery cell internal resistance × 150%;

[0024] S32, if it is determined that the internal resistance of each battery cell is less than the preset internal resistance threshold, the battery pack is subjected to a load discharge test until the battery pack is under voltage protection;

[0025] S33, charging the battery pack with low voltage protection at full power until the battery pack is over-voltage protected;

[0026] S34, after charging is completed, let it stand for a given time, wait for the temperature of the battery pack to drop to the ambient temperature, and then measure the internal resistance.

[0027] S35, repeat the internal resistance test according to steps S32 to S34, and obtain the internal resistance of each battery cell by using an average method;

[0028] S36, after obtaining the internal resistance of each battery cell, determine whether the internal resistance of each battery cell is less than 130% of the initial value of the internal resistance of the battery cell;

[0029] If the internal resistance of each battery cell is less than 130% of the initial value of the battery cell internal resistance, the battery cell is determined to meet the use requirements and the battery pack fault is eliminated;

[0030] If the internal resistance of at least one battery cell is greater than 130% of the initial value of the battery cell internal resistance, the battery pack is determined to be faulty. The battery management system reports the battery health and gives corresponding replacement recommendations.

[0031] In a second aspect, an embodiment of the present invention provides a system for handling failure of a series-connected battery pack in a battery power source, comprising:

[0032] A battery pack, composed of a plurality of battery cells connected in series, wherein the battery cells are respectively connected to a single-pole single-throw relay and a BMS control board;

[0033] A relay group, including a plurality of single-pole single-throw relays and a plurality of single-pole double-throw relays, wherein the single-pole single-throw relays are respectively connected to the battery cells and the BMS control board, and the single-pole double-throw relays are respectively connected to the spare battery cells, the BMS control board and the battery pack;

[0034] A spare battery cell connected to the single-pole double-throw relay;

[0035] The BMS control board is connected to the battery pack, the relay group and the constant current load respectively, and is used to periodically detect the internal resistance of each battery cell in the battery pack and identify the faulty battery cell; after confirming the faulty battery cell, the single-pole single-throw relay is controlled to disconnect the faulty battery cell, and the single-pole double-throw relay is controlled to connect the disconnected fault line with the spare battery cell, and the spare battery cell is connected to the battery pack;

[0036] The constant current load is connected to the battery pack and the BMS control board respectively, and is used to apply a constant current load to detect the terminal voltage and internal resistance of the battery cell.

[0037] In a third aspect, the present invention further provides a BMS control board, comprising:

[0038] The battery cell internal resistance measurement module is used to periodically detect the internal resistance of each battery cell in the battery pack through the DC discharge method to identify the faulty battery cell;

[0039] The spare cell switching control module is used to control the battery management system to control the relay to disconnect the faulty cell and connect the spare cell to the battery pack after confirming the faulty cell;

[0040] The battery performance test module is used for the battery management system to perform performance tests on the internal resistance of the battery cells in the battery pack after the spare battery cells are put into use, so as to confirm whether each battery cell in the battery pack meets the use requirements.

[0041] In a fourth aspect, the present invention further provides an electronic device, comprising a memory and a processor, wherein:

[0042] The memory is used to store programs;

[0043] The processor is coupled to the memory and is used to execute the program stored in the memory to implement the steps in the method for handling failure of series-connected battery packs in a battery power source as described in the embodiment of the first aspect of the present invention.

[0044] In a fifth aspect, the present invention further provides a computer-readable storage medium for storing computer-readable programs or instructions, which, when executed by a processor, can implement the steps in the method for handling failure of a series battery pack in a battery power supply as described in the embodiment of the first aspect of the present invention.

[0045] Compared with the prior art, the method and system for handling failure of series-connected battery packs in a battery power supply provided by the present invention have the following beneficial effects:

[0046] 1) Compared with the traditional battery fault handling method that screens and weakens faults before and during the event, the present invention can detect and identify the faulty cells in the battery pack after the battery fault occurs and replace them with spare cells, thereby eliminating the fault immediately and ensuring the continuous and stable operation of the battery pack. By replacing the faulty cells immediately, the present invention avoids the risk of performance degradation or failure of the entire battery pack due to a single cell failure, thereby improving the reliability and stability of the system.

[0047] 2) The present invention aims at the problem of failure of battery cells in series in mining battery power sources. The internal resistance of the battery cells is periodically detected by a DC discharge method, and abnormal battery cells are identified and replaced in time, thereby fundamentally solving the problem of battery pack failure caused by the increase of the internal resistance of a single battery cell.

[0048] 3) By timely replacing faulty cells, the present invention can significantly extend the service life of the battery pack, thereby increasing the usage time and economic benefits, which is particularly important for unmanned high-reliability mining equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 A flow chart of a method for handling failure of a series-connected battery pack in a battery power supply provided by the present invention;

[0050] Figure 2 A schematic diagram of a method for handling failure of a series-connected battery pack in a battery power source provided by the present invention;

[0051] Figure 3 A structural block diagram of a failure processing system for series-connected battery packs in a battery power source provided by the present invention;

[0052] Figure 4 A circuit diagram of a failure processing system for series-connected battery packs in a battery power source provided by the present invention;

[0053] Figure 5 This is a structural block diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0054] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0055] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0056] Existing methods for handling battery cell faults, such as fault isolation, active / passive balancing, and consistency screening, are all designed to screen and weaken faults before and during the event to postpone the occurrence of the fault. Although this can increase the service life of the battery pack to a certain extent, it cannot fundamentally solve the problem of battery pack failure caused by increased internal resistance of the battery cell.

[0057] In view of this, the present invention provides a method for handling failure of a series battery pack in a battery power source, which periodically detects (such as 48 hours) the internal resistance of each battery cell in the battery pack during battery self-maintenance to identify the faulty battery cell. For the battery cell with abnormal internal resistance that affects the normal operation of the battery pack, the system automatically bypasses the faulty battery cell with a spare battery cell, thereby solving the problem of the battery pack in a high-reliability battery power source for mining causing the performance of the entire lithium battery pack to decline due to the poor health of individual batteries. The following will be explained and introduced through multiple embodiments.

[0058] It is understandable that when lithium iron phosphate batteries leave the factory, usually 10% to 20% of the cells will show significant internal resistance differences. In order to reduce this difference, we use consistency screening and active or passive balancing technology, which can effectively control the internal resistance difference within 2%. However, in the field of mining battery power supplies, especially in high-power and high-reliability application scenarios, battery packs are often composed of 16 to 168 single-string cells. As the number of single-string cells increases, the probability of cell failure also increases. It is precisely to this challenge that the present invention proposes an innovative solution to effectively solve the problem of cell failure in a single-string battery pack and ensure the stable operation and long-term use of the battery pack.

[0059] Figure 1 A flow chart of a method for handling failure of a series-connected battery pack in a battery power source provided by the present invention, Figure 2 The schematic diagram of the method for handling failure of series-connected battery packs in the battery power source provided by the present invention is shown in FIG. Figure 1 As shown, the method for handling failure of a series battery pack in a battery power source includes at least the following steps:

[0060] Step S1, performing periodic detection on the internal resistance of each battery cell in the battery pack by a direct current discharge method to identify the faulty battery cell.

[0061] Specifically, internal resistance is an important indicator that reflects the health status of the battery cell. By measuring the internal resistance, abnormal changes in the battery cell can be discovered in time. In this embodiment, in order to detect the failure of the battery pack in time, the battery management system (Battery Management System, referred to as BMS) will regularly perform internal resistance detection on each battery cell in the battery pack. The detection cycle in this embodiment is set to 48 hours, which can be adjusted as needed in actual applications. During the periodic detection process, the battery management system will analyze the internal resistance data of each battery cell and compare it with the preset internal resistance threshold to identify battery cells that may have faults.

[0062] Figure 3 A structural block diagram of a failure processing system for series-connected battery packs in a battery power source provided by the present invention; Figure 4 A circuit diagram of a series battery pack failure processing system in a battery power source provided by the present invention; Figure 3 and Figure 4 The series battery pack failure processing system in the battery power supply provided by the present invention comprises a battery pack, a relay pack, a spare battery cell, a BMS control board and a constant current load; wherein:

[0063] The battery pack is formed by connecting a plurality of cells in series, and the cells are respectively connected to a single-pole single-throw relay and a BMS control board. The battery pack in this embodiment can be a lithium battery pack.

[0064] The relay group includes a plurality of single-pole single-throw relays and a plurality of single-pole double-throw relays, wherein the single-pole single-throw relays are respectively connected to the battery cells and the BMS control board, and the single-pole double-throw relays are respectively connected to the spare battery cells, the BMS control board and the battery pack.

[0065] A spare battery cell is connected to the single-pole double-throw relay.

[0066] The BMS control board is connected to the battery pack, the relay group and the constant current load respectively, and is used to periodically detect the internal resistance of each battery cell in the battery pack and identify the faulty battery cell; after confirming the faulty battery cell, the single-pole single-throw relay is controlled to disconnect the faulty battery cell, and the single-pole double-throw relay is controlled to connect the disconnected fault line with the spare battery cell, and the spare battery cell is connected to the battery pack. In the embodiment of the present invention, the BMS control board refers to the battery management system.

[0067] The constant current load is connected to the battery pack and the BMS control board respectively, and is used to apply a constant current load to detect the terminal voltage and internal resistance of the battery cell.

[0068] In a preferred embodiment of the present invention, step S1 may specifically include the following steps S11 to S16:

[0069] S11, measuring the terminal voltage V1 of each battery cell in the no-load state of the battery pack;

[0070] Obtain the voltage reference of the battery pack in the no-load state. By measuring the terminal voltage of each battery cell, the initial state of the battery pack can be understood, providing an accurate initial voltage value for the subsequent internal resistance calculation.

[0071] S12, turn on the constant current electronic load, discharge the battery pack with a given constant current I, and continuously detect the cell terminal voltage until it stabilizes.

[0072] In this embodiment, the battery pack is discharged at a constant current of 0.5C, and the change of the cell terminal voltage can be observed. Continuously detecting the cell terminal voltage until it is stable can ensure that the cell voltage is stable during the discharge process, so that the internal resistance can be accurately calculated.

[0073] S13, after confirming that the cell terminal voltage is stable, record the cell voltage value V2 and collect the temperature of each cell.

[0074] In this embodiment, when the fluctuation of the terminal voltage of the battery cell is less than 0.02V within 30S, the terminal voltage is considered to be stable, and the battery cell voltage at this time is recorded, with the value retained to three decimal places, and the temperature of each battery cell is collected synchronously.

[0075] S14, after determining that the temperature of each battery cell is stable according to the preset conditions, determining that the battery cell voltage value is valid.

[0076] Specifically, since temperature has a certain influence on internal resistance, in order to ensure that the recorded cell voltage value is valid when the temperature is stable, in this embodiment, the cell temperature is within ±1°C, that is, the cell terminal voltage value under loading is considered valid.

[0077] S15, calculating the internal resistance of each battery cell according to the initial voltage V1 in the no-load state, the voltage value V2 after the battery cell terminal voltage is stabilized, and the applied constant current I;

[0078] Specifically, using Ohm's law, the internal resistance of each battery cell can be calculated based on the initial voltage, the stabilized voltage, and the applied current. The internal resistance of the battery cell can be calculated according to the following formula:

[0079]

[0080] Where V1 is the initial voltage under no-load condition, V2 is the voltage value after the cell terminal voltage stabilizes, and I is the applied constant current.

[0081] S16, when the internal resistance of the battery cell exceeds the preset internal resistance threshold, return to steps S12 to S15 to perform a second measurement on the internal resistance of the battery cell. If the internal resistance of the battery cell still exceeds the preset internal resistance threshold after the second measurement, it is determined to be a faulty battery cell.

[0082] Specifically, the preset internal resistance threshold = the initial value of the battery cell internal resistance × 150%. When the battery cell internal resistance rises to 150% of the initial value, the secondary battery cell internal resistance measurement is started. When the battery cell internal resistance is still greater than 150% of the initial value after two measurements, it is determined that the battery cell is faulty and needs to be replaced.

[0083] In this embodiment, in order to ensure the accuracy of the internal resistance measurement, when the internal resistance of the battery cell exceeds the preset internal resistance threshold, a secondary measurement is performed to eliminate the error caused by accidental factors. If the internal resistance of the battery cell still exceeds the threshold after the secondary measurement, it can be determined that the battery cell is a faulty battery cell and needs to be replaced.

[0084] Step S2, after confirming the faulty battery cell, the battery management system controls the relay to disconnect the faulty battery cell and connect the spare battery cell to the battery pack.

[0085] In a preferred embodiment of the present invention, step S2 may specifically include the following steps:

[0086] S21, when the battery management system confirms the faulty cell, the system controls the single-pole single-throw relay to disconnect the faulty cell; wherein each cell is connected to a single-pole single-throw relay, and the single-pole single-throw relay is closed in the initial state; the spare cell is connected to one contact of the single-pole double-throw relay, and the other contact of the single-pole double-throw relay is connected to the series circuit of the battery pack.

[0087] Specifically, after detecting and identifying the faulty cell in step S1, the battery management system BMS will immediately send a signal to the corresponding single-pole single-throw relay to disconnect it from the faulty cell. In this way, the faulty cell is effectively isolated from the battery pack to prevent it from continuing to affect the performance and life of the entire battery pack.

[0088] S22, the battery management system connects the disconnected fault line with the spare battery cell through the single-pole double-throw relay, and connects the spare battery cell to the battery pack; wherein, the battery management system adopts a mutually exclusive signal method to control the single-pole single-throw relay and the single-pole double-throw relay respectively to ensure that the two relays are not closed at the same time.

[0089] Specifically, after the faulty cell is isolated, the battery management system will immediately control the single-pole double-throw relay to connect the spare cell to the position of the original faulty cell, thereby maintaining the integrity and continuity of the battery pack. The timely connection of the spare cell ensures that the battery pack can continue to work normally and will not cause the failure of the entire battery pack due to the failure of one cell.

[0090] Furthermore, in order to prevent the faulty battery cell and the spare battery cell from being put into use at the same time due to a BMS control failure, resulting in the abnormality of two battery cells being connected in parallel, the battery management system BMS uses a mutually exclusive signal method to control the two relays separately. The contacts of the single-pole single-throw relay and the single-pole double-throw relay are closed mutually exclusive. When the single-pole single-throw relay disconnects the faulty battery cell, the single-pole double-throw relay will close and connect the spare battery cell to the battery pack. This control strategy greatly improves the reliability and safety of the switching process.

[0091] Step S3, after the spare battery cells are put into use, the battery management system performs a performance test on the internal resistance of the battery cells in the battery pack to confirm whether each battery cell in the battery pack meets the use requirements.

[0092] In a preferred embodiment of the present invention, step S3 may specifically include the following steps:

[0093] S31, after the spare battery cell is put into use, the battery management system detects the internal resistance of the battery cell in the battery pack to determine whether the internal resistance is less than a preset internal resistance threshold; wherein the preset internal resistance threshold = the initial value of the battery cell internal resistance × 150%.

[0094] Specifically, in order to confirm whether the overall internal resistance of the battery pack remains within a reasonable range after the backup cell is connected. By setting a preset internal resistance threshold (initial value of the cell internal resistance × 150%), possible abnormal cells can be quickly screened out. If the internal resistance exceeds the preset internal resistance threshold, it means that the cell may be faulty or have degraded performance, and further inspection or processing is required. This step ensures the stability and reliability of the battery pack after the backup cell is connected.

[0095] S32, if it is determined that the internal resistance of each battery cell is less than the preset internal resistance threshold, a load discharge test is performed on the battery pack until the battery pack is under voltage protection.

[0096] Specifically, after confirming that the internal resistance of each cell in the battery pack is normal, the actual performance of the battery pack can be further verified by loading and discharging test. Discharging to low voltage protection simulates the discharge process of the battery pack in actual use to test the discharge capacity and stability of the battery pack. This step helps to discover possible hidden faults or performance problems.

[0097] S33, charging the battery pack with low voltage protection at full power until the battery pack is over-voltage protected.

[0098] Specifically, charging to overvoltage protection can simulate the charging process of the battery pack in actual use. By charging at full power, the charging performance and safety of the battery pack can be tested.

[0099] S34, after charging is completed, let it stand for a given time, wait for the temperature of the battery pack to drop to the ambient temperature, and then measure the internal resistance.

[0100] Specifically, leaving the battery pack to stand still after charging and waiting for the temperature of the battery pack to drop to the ambient temperature can eliminate the influence of the heat generated during the charging process on the internal resistance measurement.

[0101] S35, repeat the internal resistance test according to steps S32 to S34, and obtain the internal resistance of each battery cell by using an average method.

[0102] In this embodiment, by repeating the internal resistance test and obtaining the internal resistance of each battery cell by the averaging method, the accuracy and reliability of the battery cell internal resistance measurement can be improved. Multiple measurements and averaging can reduce the influence of errors and accidental factors, making the results more representative.

[0103] S36, after obtaining the internal resistance of each battery cell, determine whether the internal resistance of each battery cell is less than 130% of the initial value of the battery cell internal resistance; if the internal resistance of each battery cell is less than 130% of the initial value of the battery cell internal resistance, it is determined that the battery cell meets the usage requirements and the battery pack fault is eliminated; if the internal resistance of at least one battery cell is greater than 130% of the initial value of the battery cell internal resistance, it is determined that the battery pack has a fault, and the battery management system reports the battery health and gives corresponding replacement suggestions.

[0104] Specifically, after obtaining the internal resistance of each battery cell, if the internal resistance of each battery cell is less than 130% of the initial value of the internal resistance of the battery cell, it is determined that the battery cell meets the usage requirements and the battery pack fault is eliminated.

[0105] If the internal resistance of at least one battery cell is greater than 130% of the initial value of the battery cell internal resistance and greater than 150% of the initial value of the battery cell internal resistance, the battery management system BMS reports that the battery health is 70%, and it is recommended that the battery pack be replaced within 60 days.

[0106] If the internal resistance of at least one battery cell is greater than 150% of the initial value of the battery cell internal resistance and less than 250% of the initial value of the battery cell internal resistance, the battery management system BMS system reports that the battery health is 50%, and it is recommended to replace the battery pack as soon as possible.

[0107] If the internal resistance of at least one battery cell is greater than 250% of the initial value of the battery cell internal resistance, the battery management system BMS system reports that the battery health is 30%, and it is recommended to replace the battery pack immediately.

[0108] Compared with the prior art, the method for handling failure of a series-connected battery pack in a battery power source provided by the present invention has the following beneficial effects:

[0109] 1) Compared with the traditional battery fault handling method that screens and weakens faults before and during the event, the present invention can detect and identify the faulty cells in the battery pack after the battery fault occurs and replace them with spare cells, thereby eliminating the fault immediately and ensuring the continuous and stable operation of the battery pack. By replacing the faulty cells immediately, the present invention avoids the risk of performance degradation or failure of the entire battery pack due to a single cell failure, thereby improving the reliability and stability of the system.

[0110] 2) The present invention aims at the problem of failure of battery cells in series in mining battery power sources. The internal resistance of the battery cells is periodically detected by a DC discharge method, and abnormal battery cells are identified and replaced in time, thereby fundamentally solving the problem of battery pack failure caused by the increase of the internal resistance of a single battery cell.

[0111] 3) By timely replacing faulty cells, the present invention can significantly extend the service life of the battery pack, thereby increasing the usage time and economic benefits, which is particularly important for unmanned high-reliability mining equipment.

[0112] In a preferred embodiment of the present invention, the present invention further provides a BMS control board, comprising:

[0113] The battery cell internal resistance measurement module is used to periodically detect the internal resistance of each battery cell in the battery pack through the DC discharge method to identify the faulty battery cell;

[0114] The spare cell switching control module is used to control the battery management system to control the relay to disconnect the faulty cell and connect the spare cell to the battery pack after confirming the faulty cell;

[0115] The battery performance test module is used for the battery management system to perform performance tests on the internal resistance of the battery cells in the battery pack after the spare battery cells are put into use, so as to confirm whether each battery cell in the battery pack meets the use requirements.

[0116] The BMS control board provided by the present invention executes the method for handling failure of series-connected battery packs in the battery power supply provided by the above-mentioned embodiments through the above-mentioned modules. The method for handling failure of series-connected battery packs in the battery power supply has been described in detail in the above-mentioned embodiments, and will not be repeated in this embodiment.

[0117] Figure 5 The structural block diagram of the electronic device provided by the present invention is as follows: Figure 5 As shown, the present invention also provides an electronic device, and the electronic device 500 can be a computing device such as a mobile terminal, a desktop computer, a notebook, a palm computer, and a server. The electronic device 500 includes a processor 501 and a memory 502, wherein the memory 502 stores a failure processing program 503 for a series battery pack in a battery power source.

[0118] In some embodiments, the memory 502 may be an internal storage unit of a computer device, such as a hard disk or memory of the computer device. In other embodiments, the memory 502 may also be an external storage device of a computer device, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the computer device. Furthermore, the memory 502 may also include both an internal storage unit and an external storage device of the computer device. The memory 502 is used to store application software and various types of data installed in the computer device, such as program codes installed in the computer device. The memory 502 may also be used to temporarily store data that has been output or is to be output. In one embodiment, when the series battery pack failure handling program 503 in the battery power supply is executed by the processor 501, the following steps are implemented:

[0119] Step S1, periodically testing the internal resistance of each battery cell in the battery pack by a direct current discharge method to identify the faulty battery cell;

[0120] Step S2, after confirming the faulty battery cell, the battery management system controls the relay to disconnect the faulty battery cell and connect the spare battery cell to the battery pack.

[0121] In some embodiments, the processor 501 may be a central processing unit (CPU), a microprocessor or other data processing chip, used to run program codes or process data stored in the memory 502, such as executing a failure handling program for series battery packs in a battery power source.

[0122] This embodiment further provides a computer-readable storage medium on which a failure processing program for a series-connected battery pack in a battery power source is stored. When the failure processing program 503 for a series-connected battery pack in a battery power source is executed by a processor, the following steps are implemented:

[0123] Step S1, periodically testing the internal resistance of each battery cell in the battery pack by a direct current discharge method to identify the faulty battery cell;

[0124] Step S2, after confirming the faulty battery cell, the battery management system controls the relay to disconnect the faulty battery cell and connect the spare battery cell to the battery pack.

[0125] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

[0126] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for handling failure of a series-connected battery pack in a battery power source, characterized in that: include: Step S1, periodically testing the internal resistance of each battery cell in the battery pack by a direct current discharge method to identify the faulty battery cell; Step S2, after confirming the faulty battery cell, the battery management system controls the relay to disconnect the faulty battery cell and connect the spare battery cell to the battery pack.

2. The method for handling failure of series-connected battery packs in a battery power source according to claim 1, characterized in that: Also includes: Step S3, after the spare battery cells are put into use, the battery management system performs a performance test on the internal resistance of the battery cells in the battery pack to confirm whether each battery cell in the battery pack meets the use requirements.

3. The method for handling failure of series-connected battery packs in a battery power source according to claim 1, characterized in that: In step S1, the internal resistance of each battery cell in the battery pack is periodically detected by a DC discharge method to identify a faulty battery cell, which specifically includes: S11, measure the terminal voltage of each cell in the no-load state of the battery pack V 1; S12, turn on the constant current electronic load, with a given constant current I Discharge the battery pack and continuously detect the cell terminal voltage until it stabilizes; S13, after confirming that the cell terminal voltage is stable, record the cell voltage value V 2. Collect the temperature of each battery cell; S14, after determining that the temperature of each battery cell is stable according to the preset conditions, determining that the battery cell voltage value is valid; S15, according to the initial voltage under no-load condition V 1. Voltage value after the cell terminal voltage stabilizes V 2 and the constant current applied I , calculate the internal resistance of each battery cell; S16, when the internal resistance of the battery cell exceeds the preset internal resistance threshold, return to steps S12 to S15 to perform a second measurement on the internal resistance of the battery cell. If the internal resistance of the battery cell still exceeds the preset internal resistance threshold after the second measurement, it is determined to be a faulty battery cell.

4. The method for handling failure of series-connected battery packs in a battery power source according to claim 1, characterized in that: In step S2, after confirming the faulty cell, the battery management system controls the relay to disconnect the faulty cell and connect the spare cell to the battery pack, which specifically includes: S21, when the battery management system confirms the faulty cell, the system controls the single-pole single-throw relay to disconnect the faulty cell; wherein each cell is connected to a single-pole single-throw relay, and the single-pole single-throw relay is closed in the initial state; The spare battery cell is connected to one contact of a single-pole double-throw relay, and the other contact of the single-pole double-throw relay is connected to the series circuit of the battery pack; S22, the battery management system connects the disconnected fault line with the spare battery cell through the single-pole double-throw relay, and connects the spare battery cell to the battery pack; Among them, the battery management system adopts a mutually exclusive signal method to control the single-pole single-throw relay and the single-pole double-throw relay respectively to ensure that the two relays are not closed at the same time.

5. The method for handling failure of series-connected battery packs in a battery power source according to claim 2, characterized in that: In step S3, after the spare battery cell is put into use, the battery management system performs a performance test on the internal resistance of the battery cell in the battery pack to confirm whether each battery cell in the battery pack meets the use requirements, specifically including: S31, after the spare battery cell is put into use, the battery management system detects the internal resistance of the battery cell in the battery pack to determine whether the internal resistance is less than a preset internal resistance threshold; wherein the preset internal resistance threshold = the initial value of the battery cell internal resistance × 150%; S32, if it is determined that the internal resistance of each battery cell is less than the preset internal resistance threshold, the battery pack is subjected to a load discharge test until the battery pack is under voltage protection; S33, charging the battery pack with low voltage protection at full power until the battery pack is over-voltage protected; S34, after charging is completed, let the battery pack stand for a given period of time, wait for the battery pack temperature to drop to the ambient temperature, and then measure the internal resistance; S35, repeat the internal resistance test according to steps S32 to S34, and obtain the internal resistance of each battery cell by using an average method; S36, after obtaining the internal resistance of each battery cell, determine whether the internal resistance of each battery cell is less than 130% of the initial value of the internal resistance of the battery cell; If the internal resistance of each battery cell is less than 130% of the initial value of the battery cell internal resistance, the battery cell is determined to meet the use requirements and the battery pack fault is eliminated; If the internal resistance of at least one battery cell is greater than 130% of the initial value of the battery cell internal resistance, the battery pack is determined to be faulty. The battery management system reports the battery health and gives corresponding replacement recommendations.

6. A system for handling failure of series-connected battery packs in a battery power source, characterized in that: include: A battery pack, composed of a plurality of battery cells connected in series, wherein the battery cells are respectively connected to a single-pole single-throw relay and a BMS control board; A relay group, including a plurality of single-pole single-throw relays and a plurality of single-pole double-throw relays, wherein the single-pole single-throw relays are respectively connected to the battery cells and the BMS control board, and the single-pole double-throw relays are respectively connected to the spare battery cells, the BMS control board and the battery pack; A spare battery cell connected to the single-pole double-throw relay; The BMS control board is connected to the battery pack, the relay group and the constant current load respectively, and is used to periodically detect the internal resistance of each battery cell in the battery pack and identify the faulty battery cell; after confirming the faulty battery cell, the single-pole single-throw relay is controlled to disconnect the faulty battery cell, and the single-pole double-throw relay is controlled to connect the disconnected fault line with the spare battery cell, and the spare battery cell is connected to the battery pack; The constant current load is connected to the battery pack and the BMS control board respectively, and is used to apply a constant current load to detect the terminal voltage and internal resistance of the battery cell.

7. A BMS control board, characterized in that: include: The battery cell internal resistance measurement module is used to periodically detect the internal resistance of each battery cell in the battery pack through the DC discharge method to identify the faulty battery cell; The spare cell switching control module is used to control the battery management system to control the relay to disconnect the faulty cell and connect the spare cell to the battery pack after confirming the faulty cell; The battery performance test module is used for the battery management system to perform performance tests on the internal resistance of the battery cells in the battery pack after the spare battery cells are put into use, so as to confirm whether each battery cell in the battery pack meets the use requirements.

8. An electronic device, It is characterized in that comprising a memory and a processor, wherein: The memory is used to store programs; The processor is coupled to the memory and is used to execute the program stored in the memory to implement the steps in the method for handling failure of a series battery pack in a battery power source as described in any one of claims 1 to 5 above.

9. A computer-readable storage medium, characterized in that: Used to store computer-readable programs or instructions, which, when executed by a processor, can implement the steps of the method for handling failure of a series battery pack in a battery power source as described in any one of claims 1 to 5 above.

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