Battery pack charging and discharging method, device, equipment and computer readable storage medium

Abstract

The present invention discloses a battery pack charging and discharging method, device, equipment and computer-readable storage medium, which belongs to the field of battery management and is used to manage the charging and discharging of the battery pack, solving the problems of low working efficiency and short life of the battery pack. When the battery pack starts to charge or discharge, the imbalance degree of the power of each battery in the battery pack is determined. When the imbalance degree is in a first preset interval, the power of each battery in the battery pack is made consistent by limiting the battery charging and discharging rate. When the imbalance degree is in a second preset interval (greater than the first preset interval), the power of each battery in the battery pack is made consistent by controlling the on and off of the battery charging and discharging circuit, which not only improves the working efficiency of the battery pack and prolongs the service life, but also improves the charging and discharging efficiency and reduces the waste of electric energy.

Description

Technical Field

[0001] The present invention relates to the field of battery management, and in particular to a method, device, equipment and computer-readable storage medium for charging and discharging a battery pack. Background Art

[0002] A battery pack composed of multiple batteries can be used as a power source in various fields. The working process of the battery pack involves the charging and discharging process of each battery. However, due to some reasons, it is difficult for each battery in the battery pack to achieve balanced charging and discharging, that is, it is difficult for each battery in the battery pack to complete charging and discharging at the same time. This phenomenon not only reduces the working efficiency of the battery pack, but also reduces the service life of the battery pack.

[0003] Therefore, how to provide a solution to the above technical problems is a problem that those skilled in the art need to solve at present. Summary of the invention

[0004] The object of the present invention is to provide a battery pack charging and discharging method, device, equipment and computer-readable storage medium, which not only improves the working efficiency of the battery pack and extends the service life of the battery pack, but also can reduce the impact on the charging and discharging efficiency by limiting the charging and discharging rate when the imbalance degree of the power is small, and reduce the waste of electric energy by controlling the on and off of the battery charging and discharging circuit when the imbalance degree of the power is high.

[0005] In order to solve the above technical problems, the present invention provides a charging and discharging method of a battery pack, comprising:

[0006] When the battery pack starts to charge or discharge, determine the imbalance degree of the power of each battery in the battery pack;

[0007] If the imbalance degree is within a first preset range, the charge and discharge rates of the batteries are limited so that the power levels of the batteries in the battery pack are consistent;

[0008] If the imbalance degree is within a second preset range, the charge and discharge circuits of the batteries are controlled to be on and off so that the charge levels of the batteries in the battery pack are consistent;

[0009] The maximum value of the first preset interval is not greater than the minimum value of the second preset interval.

[0010] On the other hand, when the battery pack starts to charge or discharge, determining the imbalance degree of the power of each battery in the battery pack includes:

[0011] When the battery pack starts to charge or discharge, the power difference between two batteries with the largest power difference in the battery pack is determined, and the power difference is used as the degree of imbalance of power of each battery in the battery pack.

[0012] On the other hand, limiting the battery charge and discharge rate so that the power of each battery in the battery pack reaches the same level includes:

[0013] Determine the two batteries with the largest current power difference in the battery pack as the target battery pair;

[0014] If the battery pack is in charging mode, the charging rate of the battery with higher charge in the target battery pair is limited; if the battery pack is in discharging mode, the discharging rate of the battery with lower charge in the target battery pair is limited until the charge levels of the two batteries in the target battery pair are consistent;

[0015] Determining whether the power levels of the batteries in the battery pack are consistent;

[0016] If the power levels of the batteries in the battery pack are not consistent, determining two batteries with the largest current power difference in the battery pack as the target battery pair;

[0017] If the power levels of the batteries in the battery pack are consistent, the process ends.

[0018] On the other hand, the method of controlling the on-off of the battery charging and discharging circuit to make the power of each battery in the battery pack consistent includes:

[0019] Determine the two batteries with the largest current power difference in the battery pack as the target battery pair;

[0020] If the battery pack is in charging mode, the charging circuit of the battery with higher charge in the target battery pair is cut off; if the battery pack is in discharging mode, the discharging circuit of the battery with lower charge in the target battery pair is cut off until the charge levels of the two batteries in the target battery pair are consistent;

[0021] Determining whether the power levels of the batteries in the battery pack are consistent;

[0022] If the power levels of the batteries in the battery pack are not consistent, determining two batteries with the largest current power difference in the battery pack as the target battery pair;

[0023] If the power levels of the batteries in the battery pack are consistent, the process ends.

[0024] On the other hand, the method of controlling the on-off of the battery charging and discharging circuit to make the power of each battery in the battery pack consistent includes:

[0025] Determine the two batteries with the largest current power difference in the battery pack as the target battery pair;

[0026] If the battery pack is in a charging mode, the charging circuit of the battery with a higher charge in the target battery pair is cut off until the battery with a lower charge in the target battery pair is fully charged; if the battery pack is in a discharging mode, the discharging circuit of the battery with a lower charge in the target battery pair is cut off until the battery with a higher charge in the target battery pair is discharged;

[0027] Determining whether the power levels of the batteries in the battery pack are consistent;

[0028] If the power levels of the batteries in the battery pack are not consistent, determining two batteries with the largest current power difference in the battery pack as the target battery pair;

[0029] If the power levels of the batteries in the battery pack are consistent, the process ends.

[0030] On the other hand, when the battery pack starts to charge or discharge, the power difference between the two batteries with the largest power difference in the battery pack is determined to include:

[0031] When the battery pack starts to charge or discharge, receiving the first real-time power of each battery collected by the battery management system BMS of each battery;

[0032] When the battery pack starts to charge or discharge, the second real-time power of each battery in the battery pack is collected by a preset power collection device;

[0033] For any battery in the battery pack, if the first real-time power level of the battery is consistent with the second real-time power level of the battery, either the first real-time power level of the battery or the second real-time power level of the battery is used as the actual power level of the battery;

[0034] For any battery in the battery pack, if the first real-time power level and the second real-time power level of the battery are inconsistent, the control prompter prompts a power collection error;

[0035] After the actual power of each battery in the battery pack is determined, the difference between the actual power of the battery with the highest power and the actual power of the battery with the lowest power in the battery pack is taken as the power difference between the two batteries with the largest power difference in the battery pack.

[0036] On the other hand, the charging and discharging method of the battery pack further includes:

[0037] After the power levels of the batteries in the battery pack are controlled to be consistent, the power balancing control times are increased by one;

[0038] The control prompter prompts the power balancing control times;

[0039] When the number of times of the power balancing control reaches a preset threshold, the control prompter prompts that the battery pack is abnormal.

[0040] In order to solve the above technical problems, the present invention also provides a charging and discharging device of a battery pack, comprising:

[0041] A determination module, used to determine the degree of imbalance of power of each battery in the battery pack when the battery pack starts to charge or discharge;

[0042] A first control module, configured to make the power of each battery in the battery pack consistent by limiting the battery charge and discharge rate if the imbalance degree is within a first preset interval;

[0043] A second control module is used to make the power of each battery in the battery pack consistent by controlling the on-off of the battery charging and discharging circuit if the imbalance degree is within a second preset interval;

[0044] The maximum value of the first preset interval is not greater than the minimum value of the second preset interval.

[0045] In order to solve the above technical problems, the present invention also provides a battery pack charging and discharging device, comprising:

[0046] Memory for storing computer programs;

[0047] The processor is used to implement the steps of the battery pack charging and discharging method as described above when executing the computer program.

[0048] In order to solve the above technical problem, the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the battery pack charging and discharging method as described above are implemented.

[0049] Beneficial effect: The present invention provides a charging and discharging method for a battery pack. Considering that different power balancing methods have corresponding advantages, the present invention first determines the imbalance degree of power of each battery in the battery pack when the battery pack starts to charge or discharge. When the imbalance degree is in a first preset interval, the power of each battery in the battery pack is made consistent by limiting the battery charging and discharging rate. When the imbalance degree is in a second preset interval (greater than the first preset interval), the power of each battery in the battery pack is made consistent by controlling the on-off of the battery charging and discharging circuit. This not only improves the working efficiency of the battery pack and extends the service life of the battery pack, but also can reduce the impact on the charging and discharging efficiency by limiting the charging and discharging rate when the power imbalance degree is small. When the power imbalance degree is high, the waste of electric energy is reduced by controlling the on-off of the battery charging and discharging circuit.

[0050] The present invention also provides a battery pack charging and discharging device, equipment and computer-readable storage medium, which have the same beneficial effects as the above battery pack charging and discharging method. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the relevant technologies and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0052] Figure 1 A schematic flow chart of a charging and discharging method of a battery pack provided by the present invention;

[0053] Figure 2 A schematic diagram of the structure of a charging and discharging circuit of a battery pack provided by the present invention;

[0054] Figure 3 A schematic diagram of the structure of a charging and discharging device of a battery pack provided by the present invention;

[0055] Figure 4 A schematic structural diagram of a charging and discharging device for a battery pack provided by the present invention. DETAILED DESCRIPTION

[0056] The core of the present invention is to provide a battery pack charging and discharging method, device, equipment and computer-readable storage medium, which not only improves the working efficiency of the battery pack and extends the service life of the battery pack, but also can reduce the impact on the charging and discharging efficiency by limiting the charging and discharging rate when the imbalance degree of the power is small, and reduce the waste of electric energy by controlling the on and off of the battery charging and discharging circuit when the imbalance degree of the power is high.

[0057] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0058] Please refer to Figure 1 , Figure 1 A schematic flow chart of a charging and discharging method of a battery pack provided by the present invention, wherein the charging and discharging method of the battery pack comprises:

[0059] S101: When the battery pack starts to charge or discharge, determining the degree of imbalance of power of each battery in the battery pack;

[0060] Specifically, taking into account the technical problems in the above background technology, and considering the situation of unbalanced power among the batteries in the battery pack, different power balancing methods have corresponding advantages. Therefore, in the embodiment of the present invention, it is first desired to determine the degree of unbalance in power among the batteries in the battery pack when the battery pack is working, and then adopt different power balancing methods according to the interval of the unbalanced degree, so as to obtain a more optimized power balancing solution. Therefore, in the embodiment of the present invention, the degree of unbalance in power among the batteries in the battery pack can be determined when the battery pack starts to charge or discharge, so as to use it as the data basis for subsequent steps.

[0061] Among them, the battery pack can be applied to various fields, which includes at least two batteries.

[0062] Specifically, considering that if the batteries in the battery pack have unbalanced charge before charging or discharging begins, the subsequent charging or discharging process will undoubtedly affect the efficiency or life of the battery pack. Therefore, in an embodiment of the present invention, the degree of imbalance in the charge of each battery in the battery pack can be determined when the battery pack starts charging or discharging, so as to perform subsequent charge balancing actions.

[0063] S102: if the degree of imbalance is within a first preset range, limiting the battery charge and discharge rate so that the power of each battery in the battery pack reaches a consistent level;

[0064] Specifically, in order to distinguish the magnitude of the imbalance, a first preset interval and a second preset interval are set in the embodiment of the present invention. The first preset interval is smaller than the second preset interval, and there is no intersection between the first preset interval and the second preset interval.

[0065] Specifically, considering that "the method of limiting the battery charge and discharge rate" can keep the charge and discharge actions of each battery uninterrupted, there is a problem of power loss. When the degree of imbalance is small, since the process of power balance control is short, the power loss is relatively small. Therefore, in this step, when the degree of imbalance is in the first preset interval, the power of each battery in the battery pack can be made consistent by limiting the battery charge and discharge rate, thereby keeping the charge and discharge actions of each battery uninterrupted with a small power loss, thereby ensuring the charge and discharge efficiency.

[0066] The first preset interval and the second preset interval can be set independently, and the embodiment of the present invention does not limit this.

[0067] S103: if the imbalance degree is within the second preset range, the charge and discharge circuits of the batteries are controlled to be on and off so that the power levels of the batteries in the battery pack are consistent;

[0068] The maximum value of the first preset interval is not greater than the minimum value of the second preset interval.

[0069] Specifically, considering that when the degree of imbalance is high (that is, it is in the second preset interval), the process required for power balance control is long, so if the "method of limiting the battery charging and discharging rate" is adopted, a large amount of electric energy will be lost. Considering that the method of "controlling the on-off of the battery's charging and discharging circuit" will not increase the power loss, in this step, when the degree of imbalance is in the second preset interval, the power of each battery in the battery pack can be made consistent by controlling the on-off of the battery's charging and discharging circuit, thereby avoiding power loss.

[0070] The present invention provides a charging and discharging method for a battery pack. Considering that different power balancing methods have corresponding advantages, the present invention first determines the imbalance degree of power of each battery in the battery pack when the battery pack starts to charge or discharge. When the imbalance degree is in a first preset interval, the power of each battery in the battery pack is made consistent by limiting the battery charging and discharging rate. When the imbalance degree is in a second preset interval (greater than the first preset interval), the power of each battery in the battery pack is made consistent by controlling the on-off of the battery charging and discharging circuit. This not only improves the working efficiency of the battery pack and extends the service life of the battery pack, but also can reduce the impact on the charging and discharging efficiency by limiting the charging and discharging rate when the power imbalance degree is small. When the power imbalance degree is high, the waste of electric energy is reduced by controlling the on-off of the battery charging and discharging circuit.

[0071] Based on the above embodiments:

[0072] As an optional embodiment, when the battery pack starts to charge or discharge, determining the imbalance degree of power of each battery in the battery pack includes:

[0073] When the battery pack starts to charge or discharge, the power difference between two batteries with the largest power difference in the battery pack is determined, and the power difference is used as the degree of imbalance of power among the batteries in the battery pack.

[0074] Specifically, considering that "the charge difference between the two batteries with the largest charge difference in the battery pack" can, to a large extent, represent the degree of imbalance in the charge of each battery in the battery pack, that is, "the charge difference between the two batteries with the largest charge difference in the battery pack" is usually proportional to "the degree of imbalance in the charge of each battery in the battery pack", and the method for determining "the charge difference between the two batteries with the largest charge difference in the battery pack" is relatively simple, therefore, in an embodiment of the present invention, the charge difference between the two batteries with the largest charge difference in the battery pack can be determined when the battery pack starts to charge or discharge, and the charge difference can be used as the degree of imbalance in the charge of each battery in the battery pack, which can simplify the calculation process and improve work efficiency.

[0075] Among them, in an embodiment of the present invention, the first preset interval and the second preset interval can be specifically in various forms. For example, the first preset interval can be a first preset power to a second preset power, and the second preset interval can be a third preset power to a fourth preset power. The first preset power to the fourth preset power increase sequentially, and the first preset power to the fourth preset power can be flexibly set. For example, the first preset power can be 5% of the capacity of a single battery (in the battery pack), the second preset power can be 20% of the capacity of a single battery, the third preset power can be 21% of the capacity of a single battery, the fourth preset power can be 40% of the capacity of a single battery, etc. The embodiment of the present invention is not limited here.

[0076] Of course, in addition to this specific method, when the battery pack starts to charge or discharge, determining the imbalance degree of the power of each battery in the battery pack can also be achieved in other ways, which are not limited in the embodiment of the present invention.

[0077] As an optional embodiment, limiting the battery charge and discharge rate so that the power of each battery in the battery pack reaches the same level includes:

[0078] Determine the two batteries with the largest current power difference in the battery pack as the target battery pair;

[0079] If the battery pack is in charging mode, the charging rate of the battery with higher charge in the target battery pair is limited; if the battery pack is in discharging mode, the discharging rate of the battery with lower charge in the target battery pair is limited until the charge levels of the two batteries in the target battery pair are consistent;

[0080] Determine whether the power levels of all batteries in the battery pack are consistent;

[0081] If the power levels of the batteries in the battery pack are not consistent, determining two batteries with the largest current power difference in the battery pack as the target battery pair;

[0082] If the power levels of the batteries in the battery pack are consistent, the process ends.

[0083] Specifically, in the embodiment of the present invention, the two batteries with the largest current power difference in the battery pack can be determined each time as the target battery pair. For the target battery pair, the power of the two batteries in the target battery pair can be adjusted to a consistent power by "limiting the battery charging and discharging rate", and this cycle is repeated until the power of each battery in the battery pack is consistent.

[0084] Among them, the control method in the embodiment of the present invention is simple, efficient and not prone to errors.

[0085] Of course, in addition to this specific form, "limiting the battery charge and discharge rates so that the power levels of the batteries in the battery pack are consistent" may also be other specific implementations, which are not limited in the embodiments of the present invention.

[0086] Specifically, there are many ways to "limit the battery charge and discharge rate". For example, an adjustable resistor can be connected in parallel to each battery, and then the charge and discharge efficiency of the battery to which the adjustable resistor belongs can be changed by adjusting the resistance value of the adjustable resistor. This adjustment method has the advantages of being simple and low-cost.

[0087] Of course, “limiting the battery charge and discharge rate” may also be achieved through other methods, which are not limited in the embodiments of the present invention.

[0088] As an optional embodiment, the method of controlling the on-off of the charging and discharging circuit of the battery so that the power of each battery in the battery pack reaches the same level includes:

[0089] Determine the two batteries with the largest current power difference in the battery pack as the target battery pair;

[0090] If the battery pack is in charging mode, the charging circuit of the battery with higher charge in the target battery pair is cut off; if the battery pack is in discharging mode, the discharging circuit of the battery with lower charge in the target battery pair is cut off until the charge levels of the two batteries in the target battery pair are consistent;

[0091] Determine whether the power levels of all batteries in the battery pack are consistent;

[0092] If the power levels of the batteries in the battery pack are not consistent, determining two batteries with the largest current power difference in the battery pack as the target battery pair;

[0093] If the power levels of the batteries in the battery pack are consistent, the process ends.

[0094] To better illustrate the embodiments of the present invention, please refer to Figure 2 , Figure 2A schematic diagram of the structure of a charging and discharging circuit of a battery pack provided by the present invention, wherein the battery pack includes n batteries from 1 to n, each battery corresponds to a controllable switch ki, i=1,2,3,...,n; the charging module can charge each battery with "controllable switch closed" through a charging and discharging inverter, and each battery with "controllable switch closed" can discharge to the power grid through the charging and discharging inverter, and the charging and discharging inverter can select the battery pack to be in charging mode or discharging mode.

[0095] Specifically, similar to the step of "making the charge of each battery in the battery pack consistent by limiting the battery charge and discharge rate" in the aforementioned embodiment, when "making the charge of each battery in the battery pack consistent by controlling the on and off of the battery charge and discharge circuit", the embodiment of the present invention can determine the two batteries with the largest current charge difference in the battery pack as the target battery pair, and then "control the on and off of the battery charge and discharge circuit" to make the charge of the two batteries in the target battery pair consistent, and repeat this cycle until the charge of each battery in the battery pack is consistent.

[0096] Specifically, the implementation method in the embodiment of the present invention is simple, efficient and error-prone.

[0097] Of course, in addition to this specific implementation, "controlling the on and off of the battery charging and discharging circuits to make the power levels of the batteries in the battery pack consistent" may also be other implementations, which are not limited in the embodiments of the present invention.

[0098] As an optional embodiment, the method of controlling the on-off of the charging and discharging circuit of the battery so that the power of each battery in the battery pack reaches the same level includes:

[0099] Determine the two batteries with the largest current power difference in the battery pack as the target battery pair;

[0100] If the battery pack is in charging mode, the charging circuit of the battery with higher charge in the target battery pair is cut off until the battery with lower charge in the target battery pair is fully charged; if the battery pack is in discharging mode, the discharging circuit of the battery with lower charge in the target battery pair is cut off until the battery with higher charge in the target battery pair is discharged;

[0101] Determine whether the power levels of all batteries in the battery pack are consistent;

[0102] If the power levels of the batteries in the battery pack are not consistent, determining two batteries with the largest current power difference in the battery pack as the target battery pair;

[0103] If the power levels of the batteries in the battery pack are consistent, the process ends.

[0104] Specifically, the embodiment of the present invention provides another implementation method of "making the power of each battery in the battery pack consistent by controlling the on and off of the battery charging and discharging circuits". First, the two batteries with the largest current power difference in the battery pack are determined as the target battery pair. However, in the embodiment of the present invention, the charging and discharging work of the battery with "lagging charging and discharging progress" in the target battery pair can be completed. That is, if the battery pack is in the charging mode, the charging circuit of the battery with higher power in the target battery pair is cut off until the battery with lower power in the target battery pair is fully charged. If the battery pack is in the discharging mode, the discharging circuit of the battery with lower power in the target battery pair is cut off until the battery with higher power in the target battery pair is discharged. Then the target battery pair is re-determined until the power of each battery in the battery pack is consistent (here, all are charged or discharged).

[0105] Among them, considering that even after the power of each battery in the battery pack is controlled to be consistent, the power of each battery may still deviate again during the subsequent charging and discharging process, the control method of sequentially controlling the charging or discharging of each battery in the embodiment of the present invention can make each battery more reliably achieve the state of "fully charged or fully discharged", which can further improve the use efficiency of the battery pack and extend the service life of the battery pack.

[0106] As an optional embodiment, when the battery pack starts to charge or discharge, determining the power difference between two batteries with the largest power difference in the battery pack includes:

[0107] When the battery pack starts to charge or discharge, receiving the first real-time power of each battery collected by the battery management system BMS of each battery;

[0108] When the battery pack starts to charge or discharge, the second real-time power of each battery in the battery pack is collected by a preset power collection device;

[0109] For any battery in the battery pack, if the first real-time power level of the battery is consistent with the second real-time power level of the battery, either the first real-time power level of the battery or the second real-time power level of the battery is used as the actual power level of the battery;

[0110] For any battery in the battery pack, if the first real-time power level of the battery is inconsistent with the second real-time power level, the control prompter prompts that the power collection error occurs;

[0111] After the actual power of each battery in the battery pack is determined, the difference between the actual power of the battery with the highest power and the actual power of the battery with the lowest power in the battery pack is taken as the power difference between the two batteries with the largest power difference in the battery pack.

[0112] Specifically, in order to more accurately determine the degree of imbalance in the power of each battery in the battery pack, the embodiment of the present invention can collect the battery power through two sets of methods. Only when the battery power collected by the two sets of methods is consistent, the collected battery power is considered reliable. Otherwise, it can prompt that the power collection error is for the staff to repair, which can improve the reliability of power balancing control.

[0113] Each battery may be equipped with a BMS (Battery Management System), so in the embodiment of the present invention, the BMS of the battery and an additional power collection device are used as two sets of power collection methods.

[0114] Of course, in addition to this specific form, the power difference between the two batteries with the largest power difference in the battery pack may also be determined in other ways, which are not limited in the embodiment of the present invention.

[0115] As an optional embodiment, the charging and discharging method of the battery pack further includes:

[0116] After the power of each battery in the battery pack is controlled to be consistent, the power balancing control times are increased by one;

[0117] The control reminder prompts the number of power balancing controls;

[0118] When the number of power balancing controls reaches a preset threshold, the control indicator prompts that the battery pack is abnormal.

[0119] Specifically, considering that the more times the power balancing control is performed, the more serious the power imbalance problem in the battery pack is, in order to facilitate the staff to discover the problem and deal with it in time, in the embodiment of the present invention, after the power of each battery in the battery pack is controlled to be consistent, the power balancing control times can be increased by one. On the one hand, the control prompter can be controlled to prompt the power balancing control times, and on the other hand, when the power balancing control times reaches a preset threshold, the control prompter can be controlled to prompt that the battery pack is abnormal. The staff can not only independently discover the situation of "too many times" through the prompted power balancing control times, but also learn that "the power balancing control times have reached the preset threshold" through the prompted battery pack abnormality.

[0120] The preset threshold value may be set independently, for example, 10 times, etc., and the embodiment of the present invention does not limit this.

[0121] Please refer to Figure 3 , Figure 3 This is a schematic diagram of the structure of a charging and discharging device of a battery pack provided by the present invention, and the charging and discharging device of the battery pack includes:

[0122] The determination module 31 is used to determine the degree of imbalance of the power of each battery in the battery pack when the battery pack starts to charge or discharge;

[0123] A first control module 32 is used to make the power of each battery in the battery pack reach the same level by limiting the battery charge and discharge rate if the imbalance degree is within a first preset range;

[0124] The second control module 33 is used to make the power of each battery in the battery pack consistent by controlling the on-off of the battery charging and discharging circuit if the imbalance degree is within the second preset range;

[0125] The maximum value of the first preset interval is not greater than the minimum value of the second preset interval.

[0126] For an introduction to the charging and discharging device of the battery pack provided by the embodiment of the present invention, please refer to the embodiment of the charging and discharging method of the battery pack described above, and the embodiment of the present invention will not be described in detail here.

[0127] Please refer to Figure 4 , Figure 4 This is a schematic diagram of the structure of a charging and discharging device of a battery pack provided by the present invention, and the charging and discharging device of the battery pack includes:

[0128] A memory 41, used for storing computer programs;

[0129] The processor 42 is used to implement the steps of the battery pack charging and discharging method in the above-mentioned embodiment when executing the computer program.

[0130] For an introduction to the charging and discharging device of the battery pack provided by the embodiment of the present invention, please refer to the embodiment of the charging and discharging method of the battery pack described above, and the embodiment of the present invention will not be described in detail here.

[0131] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the battery pack charging and discharging method in the aforementioned embodiment are implemented.

[0132] For an introduction to the computer-readable storage medium provided in the embodiment of the present invention, please refer to the aforementioned embodiment of the battery pack charging and discharging method, and the embodiment of the present invention will not be described in detail here.

[0133] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description. It should also be noted that in this specification, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements that are not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or equipment including the element.

[0134] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for charging and discharging a battery pack, characterized in that: include: When the battery pack starts to charge or discharge, determine the imbalance degree of the power of each battery in the battery pack; If the imbalance degree is within a first preset range, the charge and discharge rates of the batteries are limited so that the power levels of the batteries in the battery pack are consistent; If the imbalance degree is within a second preset range, the charge and discharge circuits of the batteries are controlled to be on and off so that the charge levels of the batteries in the battery pack are consistent; Wherein, the maximum value of the first preset interval is not greater than the minimum value of the second preset interval; The method of limiting the battery charge and discharge rate so that the power of each battery in the battery pack reaches the same level includes: Determine the two batteries with the largest current power difference in the battery pack as the target battery pair; If the battery pack is in charging mode, the charging rate of the battery with higher charge in the target battery pair is limited; if the battery pack is in discharging mode, the discharging rate of the battery with lower charge in the target battery pair is limited until the charge levels of the two batteries in the target battery pair are consistent; Determining whether the power levels of the batteries in the battery pack are consistent; If the power levels of the batteries in the battery pack are not consistent, determining two batteries with the largest current power difference in the battery pack as the target battery pair; If the power levels of the batteries in the battery pack are consistent, the process ends; The method of controlling the on-off of the battery charging and discharging circuit to make the power of each battery in the battery pack consistent includes: Determine the two batteries with the largest current power difference in the battery pack as the target battery pair; If the battery pack is in charging mode, the charging circuit of the battery with higher charge in the target battery pair is cut off; if the battery pack is in discharging mode, the discharging circuit of the battery with lower charge in the target battery pair is cut off until the charge levels of the two batteries in the target battery pair are consistent; Determining whether the power levels of the batteries in the battery pack are consistent; If the power levels of the batteries in the battery pack are not consistent, determining two batteries with the largest current power difference in the battery pack as the target battery pair; If the power levels of the batteries in the battery pack are consistent, the process ends.

2. The charging and discharging method of a battery pack according to claim 1, characterized in that: When the battery pack starts to charge or discharge, the degree of imbalance of the power of each battery in the battery pack is determined including: When the battery pack starts to charge or discharge, the power difference between two batteries with the largest power difference in the battery pack is determined, and the power difference is used as the degree of imbalance of power of each battery in the battery pack.

3. The charging and discharging method of a battery pack according to claim 2, characterized in that: The method of controlling the on-off of the battery charging and discharging circuit to make the power of each battery in the battery pack consistent includes: Determine the two batteries with the largest current power difference in the battery pack as the target battery pair; If the battery pack is in a charging mode, the charging circuit of the battery with a higher charge in the target battery pair is cut off until the battery with a lower charge in the target battery pair is fully charged; if the battery pack is in a discharging mode, the discharging circuit of the battery with a lower charge in the target battery pair is cut off until the battery with a higher charge in the target battery pair is discharged; Determining whether the power levels of the batteries in the battery pack are consistent; If the power levels of the batteries in the battery pack are not consistent, determining two batteries with the largest current power difference in the battery pack as the target battery pair; If the power levels of the batteries in the battery pack are consistent, the process ends.

4. The charging and discharging method of a battery pack according to claim 2, characterized in that: When the battery pack starts to charge or discharge, the power difference between the two batteries with the largest power difference in the battery pack is determined to include: When the battery pack starts to charge or discharge, receiving the first real-time power of each battery collected by the battery management system BMS of each battery; When the battery pack starts to charge or discharge, the second real-time power of each battery in the battery pack is collected by a preset power collection device; For any battery in the battery pack, if the first real-time power level of the battery is consistent with the second real-time power level of the battery, either the first real-time power level of the battery or the second real-time power level of the battery is used as the actual power level of the battery; For any battery in the battery pack, if the first real-time power level and the second real-time power level of the battery are inconsistent, the control prompter prompts a power collection error; After the actual power of each battery in the battery pack is determined, the difference between the actual power of the battery with the highest power and the actual power of the battery with the lowest power in the battery pack is taken as the power difference between the two batteries with the largest power difference in the battery pack.

5. The charging and discharging method of a battery pack according to any one of claims 1 to 4, characterized in that: The charging and discharging method of the battery pack further includes: After the power levels of the batteries in the battery pack are controlled to be consistent, the power balancing control times are increased by one; The control prompter prompts the power balancing control times; When the number of times of the power balancing control reaches a preset threshold, the control prompter prompts that the battery pack is abnormal.

6. A charging and discharging device for a battery pack, characterized in that: include: A determination module, used to determine the degree of imbalance of power of each battery in the battery pack when the battery pack starts to charge or discharge; A first control module, configured to make the power of each battery in the battery pack consistent by limiting the battery charge and discharge rate if the imbalance degree is within a first preset interval; A second control module is used to make the power of each battery in the battery pack consistent by controlling the on-off of the battery charging and discharging circuit if the imbalance degree is within a second preset interval; Wherein, the maximum value of the first preset interval is not greater than the minimum value of the second preset interval; The method of limiting the battery charge and discharge rate so that the power of each battery in the battery pack reaches the same level includes: Determine the two batteries with the largest current power difference in the battery pack as the target battery pair; If the battery pack is in charging mode, the charging rate of the battery with higher charge in the target battery pair is limited; if the battery pack is in discharging mode, the discharging rate of the battery with lower charge in the target battery pair is limited until the charge levels of the two batteries in the target battery pair are consistent; Determining whether the power levels of the batteries in the battery pack are consistent; If the power levels of the batteries in the battery pack are not consistent, determining two batteries with the largest current power difference in the battery pack as the target battery pair; If the power levels of the batteries in the battery pack are consistent, the process ends; The method of controlling the on-off of the battery charging and discharging circuit to make the power of each battery in the battery pack consistent includes: Determine the two batteries with the largest current power difference in the battery pack as the target battery pair; If the battery pack is in charging mode, the charging circuit of the battery with higher charge in the target battery pair is cut off; if the battery pack is in discharging mode, the discharging circuit of the battery with lower charge in the target battery pair is cut off until the charge levels of the two batteries in the target battery pair are consistent; Determining whether the power levels of the batteries in the battery pack are consistent; If the power levels of the batteries in the battery pack are not consistent, determining two batteries with the largest current power difference in the battery pack as the target battery pair; If the power levels of the batteries in the battery pack are consistent, the process ends.

7. A battery pack charging and discharging device, characterized in that: include: Memory for storing computer programs; A processor, configured to implement the steps of the battery charging and discharging method according to any one of claims 1 to 5 when executing the computer program.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the battery pack charging and discharging method according to any one of claims 1 to 5 are implemented.

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