Battery pack balancing method, device, battery management system, and storage medium

Abstract

An embodiment of the present invention provides a method, a device, a battery management system, and a storage medium for balancing a battery pack. The method includes: calculating specified battery pack parameters according to a heat dissipation formula and a specific heat capacity formula to generate a temperature rise per unit time corresponding to a balancing method; generating an accumulated temperature rise according to the temperature rise per unit time and a detected balancing time; calculating detected temperature parameters according to a preset relationship to generate a temperature difference; determining a change amount of a heat dissipation channel according to a ratio of the temperature difference to the accumulated temperature rise; and balancing the battery pack according to the change amount of the heat dissipation channel. The battery management system flexibly opens the heat dissipation channel within the upper limit of the temperature at which the chip can be used, improving the balancing efficiency and solving the problem of low utilization rate of the heat dissipation channel caused by a fixed number of opened heat dissipation channels.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of battery pack balancing, and in particular, to a method and device for balancing a battery pack, a battery management system, and a storage medium.

Background Art

[0002] Electric vehicles and hybrid electric vehicles usually use a battery pack as an energy storage system, and the battery pack is usually composed of multiple single cells connected together. Due to differences in manufacturing processes, working conditions, and battery aging degrees among the single cells, it may lead to different remaining charge values of the single cells in the battery pack. The phenomenon that the remaining charge values of the individual batteries in the battery pack are different is the imbalance phenomenon of the battery pack. The imbalance phenomenon may reduce the total capacity of the battery pack and may also damage the battery pack. In related technologies, for the imbalance phenomenon of the battery pack, the commonly used balancing methods usually include a passive balancing method with a fixed heat dissipation channel. Although the passive balancing method is simple and economical, the balancing efficiency is relatively low. The reason is that in order to prevent the chip and the daughter board from getting too hot due to resistance heat dissipation, the passive balancing method usually only opens a small number of heat dissipation channels, and the number of opened heat dissipation channels is fixed. The number of heat dissipation channels only accounts for a small part of the total number of channels, resulting in a low utilization rate of the channels.

Summary of the Invention

[0003] In view of this, the embodiments of the present invention provide a method and device for balancing a battery pack, a battery management system, and a storage medium, so as to solve the problems of low balancing efficiency and low utilization rate of heat dissipation channels in the passive balancing method.

[0004] In a first aspect, the embodiments of the present invention provide a method for balancing a battery pack, and the method includes:

[0005] Calculating specified battery pack parameters according to the heat dissipation formula and the specific heat capacity formula to generate the temperature rise per unit time corresponding to the balancing method;

[0006] Generating a cumulative temperature rise according to the temperature rise per unit time and the detected balancing time;

[0007] Generating a temperature difference according to the detected temperature parameters;

[0008] Determining the heat dissipation channel change amount according to the ratio of the temperature difference to the cumulative temperature rise;

[0009] Balancing the battery pack according to the heat dissipation channel change amount.

[0010] In a possible implementation manner, the balancing the battery pack according to the heat dissipation channel change amount includes:

[0011] Controlling the opening of the heat dissipation channels corresponding to the heat dissipation channel change amount according to the heat dissipation channel change amount;

[0012] Equalize the battery pack according to the heat dissipation channels corresponding to the set minimum number of heat dissipation channels and the heat dissipation channels corresponding to the change amount of the heat dissipation channels.

[0013] In a possible implementation, the equalization method includes voltage equalization, the temperature rise per unit time includes a first temperature rise, and the specified battery pack parameters include a voltage step and a value of an equalization resistance;

[0014] The calculation of the specified battery pack parameters according to the heat dissipation formula and the specific heat capacity formula to generate the temperature rise per unit time corresponding to the equalization method includes:

[0015] Set the voltage step according to the heat dissipation capacity of the battery pack and the high-temperature bearing capacity of the battery pack;

[0016] Calculate the voltage step and the value of the equalization resistance according to the heat dissipation formula to generate a first heat dissipation amount, and the first heat dissipation amount includes the heat dissipation amount per unit time corresponding to voltage equalization;

[0017] Calculate the first heat dissipation amount, the specific heat capacity of the slave board, and the mass of the slave board according to the specific heat capacity formula to generate the first temperature rise, and the first temperature rise includes the temperature rise per unit time corresponding to voltage equalization.

[0018] In a possible implementation, the equalization method includes capacity equalization, the temperature rise per unit time includes a second temperature rise, and the specified battery pack parameters include a capacity step and the actual voltage of the battery pack;

[0019] The calculation of the specified battery pack parameters according to the heat dissipation formula and the specific heat capacity formula to generate the temperature rise per unit time corresponding to the equalization method includes:

[0020] Set the capacity step according to the heat dissipation capacity of the battery pack and the high-temperature bearing capacity of the battery pack;

[0021] Generate the actual voltage of the battery pack according to the voltages of the individual battery cells in the battery pack detected;

[0022] Calculate the capacity step and the actual voltage of the battery pack according to the heat dissipation formula to generate a second heat dissipation amount, and the second heat dissipation amount includes the heat dissipation amount per unit time corresponding to capacity equalization;

[0023] Calculate the second heat dissipation amount, the specific heat capacity of the slave board, and the mass of the slave board according to the specific heat capacity formula to generate the second temperature rise, and the second temperature rise includes the temperature rise per unit time corresponding to capacity equalization.

[0024] In a possible implementation, the generating of the cumulative temperature rise according to the temperature rise per unit time and the detected equalization time includes:

[0025] Multiplying the first temperature rise by the equalization time to generate a cumulative temperature rise.

[0026] In a possible implementation, the generating of the cumulative temperature rise according to the temperature rise per unit time and the detected equalization time includes:

[0027] Multiplying the second temperature rise by the equalization time to generate a cumulative temperature rise.

[0028] In a possible implementation, the temperature parameter includes the ambient temperature, the upper limit of the chip's available temperature, and the temperature rise corresponding to the minimum number of heat dissipation channels;

[0029] The generating of the temperature difference according to the detected temperature parameters includes:

[0030] Adding the ambient temperature to the temperature rise corresponding to the minimum number of heat dissipation channels to generate a temperature sum value;

[0031] Subtracting the temperature sum value from the upper limit of the chip's available temperature to generate a temperature difference.

[0032] In a second aspect, an embodiment of the present invention provides an equalization device for a battery pack, the device includes:

[0033] A first generation module, configured to calculate specified battery pack parameters according to a heat dissipation formula and a specific heat capacity formula to generate a temperature rise per unit time corresponding to an equalization method;

[0034] A second generation module, configured to generate a cumulative temperature rise according to the temperature rise per unit time and the detected equalization time;

[0035] A third generation module, configured to generate a temperature difference according to the detected temperature parameters;

[0036] A determination module, configured to determine a heat dissipation channel change amount according to a ratio of the temperature difference to the cumulative temperature rise;

[0037] An equalization module, configured to equalize the battery pack according to the heat dissipation channel change amount.

[0038] In a third aspect, an embodiment of the present invention provides a battery management system, including: one or more processors; a memory; and one or more computer programs, where the one or more computer programs are stored in the memory, and the one or more computer programs include instructions that, when executed by the battery management system, cause the battery management system to execute the equalization method of the battery pack in the first aspect or any possible implementation of the first aspect.

[0039] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, which includes a stored program. When the program runs, it controls the device where the computer-readable storage medium is located to execute the equalization method of the battery pack in the first aspect or any possible implementation manner of the first aspect.

[0040] In the technical solution provided by the embodiment of the present invention, the specified battery pack parameters are calculated according to the heat dissipation formula and the specific heat capacity formula to generate the temperature rise per unit time corresponding to the equalization method; the cumulative temperature rise is generated according to the temperature rise per unit time and the detected equalization time; the detected temperature parameters are calculated according to a preset relationship to generate a temperature difference; according to the ratio of the temperature difference to the cumulative temperature rise, the change amount of the heat dissipation channel is determined; and the battery pack is equalized according to the change amount of the heat dissipation channel. The battery management system flexibly opens the heat dissipation channel within the upper limit of the temperature at which the chip can be used, improving the equalization efficiency and solving the problem of low utilization rate of the heat dissipation channel caused by the fixed number of opened heat dissipation channels.

Description of the Drawings

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0042] Figure 1 It is a flowchart of an equalization method for a battery pack provided by an embodiment of the present invention;

[0043] Figure 2 It is a schematic structural diagram of an equalization device for a battery pack provided by an embodiment of the present invention;

[0044] Figure 3 It is a schematic diagram of a battery management system provided by an embodiment of the present invention.

Detailed Embodiments

[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0046] It should be clear that the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0047] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms "a", "the", and "said" used in the embodiments of the present invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0048] It should be understood that the term "and / or" used herein is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0049] Depending on the context, the word "if" as used herein can be interpreted as "when" or "while" or "in response to determining" or "in response to detecting". Similarly, depending on the context, the phrase "if determined" or "if detected (stated condition or event)" can be interpreted as "when determined" or "in response to determining" or "when detected (stated condition or event)" or "in response to detecting (stated condition or event)".

[0050] Figure 1 A flowchart of an equalization method for a battery pack provided for the embodiments of the present invention, as Figure 1 shown, the method includes:

[0051] Step 101, set the minimum number of heat dissipation channels according to the heat dissipation capacity of the battery pack.

[0052] In the embodiments of the present invention, each step can be executed by a Battery Management System (BMS for short). The BMS includes a main board and slave boards. Each slave board corresponds to a single cell in the battery pack. The slave board is used to detect the voltage and temperature of the corresponding single cell, and transmit the voltage and temperature of the single cell to the main board through a circuit. The main board is used to determine whether the voltage and temperature of the single cell are within the normal operating range based on the voltage and temperature of the single cell. If the main board determines that the voltage and / or temperature of the single cell is not within the normal operating range, it calls the program set in the main board corresponding to the problem that the voltage and / or temperature of the single cell is not within the normal operating range, and issues a control instruction so that each module in the BMS responds to the control instruction and executes the processing of the problem. For example, after the slave board transmits the detected voltage and temperature of the single cell to the main board, if the main board determines that the temperature of the single cell is higher than the highest temperature in the normal operating temperature range, the main board requests thermal management of the single cell to reduce the temperature of the single cell.

[0053] In this step, the heat dissipation capacity of the battery pack is based on the internal structure design of the heat dissipation channels. For example, the internal structure design of the heat dissipation channels can include the size of the internal space of the heat dissipation channels. Specifically, if the heat dissipation capacity of the battery pack is good, the minimum number of heat dissipation channels can be set to a larger value; if the heat dissipation capacity of the battery pack is poor, the minimum number of heat dissipation channels can be set to a smaller value. Among them, the minimum number of heat dissipation channels is a positive integer. For example, the minimum number of heat dissipation channels is 3.

[0054] Step 102: Calculate the specified battery pack parameters according to the heat dissipation formula and the specific heat capacity formula to generate the temperature rise per unit time corresponding to the equalization method.

[0055] As an alternative solution, the specified battery pack parameters include the voltage step and the equalization resistance value, the equalization method includes voltage equalization, the temperature rise per unit time includes the first temperature rise, and the voltage equalization includes an equalization method of equalizing the battery pack according to the voltage to be equalized. At this time, step 102 specifically includes:

[0056] Step 1021a: Set the voltage step according to the heat dissipation capacity of the battery pack and the high-temperature bearing capacity of the battery pack.

[0057] In this step, the heat dissipation capacity of the battery pack is based on the internal structure of the heat dissipation channels. For example, the internal structure of the heat dissipation channels may include the size of the internal space of the heat dissipation channels. The high-temperature bearing capacity of the battery pack is based on the highest temperature that the battery pack can bear under normal conditions. The highest temperature that the battery pack can bear under normal conditions includes the upper limit temperature of the operating temperature of the battery pack. For example, if the operating temperature of the battery pack is -20 to 60 °C, then the upper limit temperature of the operating temperature is 60 °C, and the highest temperature that the battery pack can bear under normal conditions is 60 °C. In actual use, it can be determined according to the actual situation whether the high-temperature bearing capacity of the battery pack is good or poor when the highest temperature that the battery pack can bear under normal conditions is 60 °C.

[0058] Step 1022a: Calculate the voltage step and the value of the balancing resistance according to the heat dissipation formula to generate the first heat dissipation amount.

[0059] In this step, the first heat dissipation amount includes the heat dissipation amount per unit time corresponding to voltage balancing. The heat dissipation formula includes:

[0060]

[0061] Among them, Q 1 represents the first heat dissipation amount, △U represents the voltage step, R represents the value of the balancing resistance, and t represents the unit time. Among them, the unit time includes 1 min.

[0062] Step 1023a: Calculate the first heat dissipation amount, the specific heat capacity of the slave board, and the mass of the slave board according to the specific heat capacity formula to generate the first temperature rise.

[0063] In this step, the first temperature rise includes the temperature rise per unit time corresponding to voltage balancing. The specific heat capacity formula includes:

[0064] Q 1 = CM△T 1

[0065] Among them, Q 1 represents the first heat dissipation amount, C represents the specific heat capacity of the slave board, M represents the mass of the slave board, and △T 1 represents the first temperature rise.

[0066] As another alternative, the specified battery pack parameters include the capacity step and the actual voltage of the battery pack, the balancing method includes capacity balancing, the temperature rise per unit time includes the second temperature rise, and capacity balancing includes a balancing method of balancing the battery pack according to the capacity to be balanced. At this time, step 102 specifically includes:

[0067] Step 1021b: Set the capacity step according to the heat dissipation capacity of the battery pack and the high-temperature bearing capacity of the battery pack.

[0068] Step 1022b: Generate the actual voltage of the battery pack based on the voltages of the individual battery cells in the detected battery pack.

[0069] In this step, the BMS detects the voltages of the individual battery cells in the battery pack, calculates the maximum and minimum individual battery cell voltages, and generates the actual voltage of the battery pack. The maximum individual battery cell voltage includes the maximum voltage among the voltages of the individual battery cells, and the minimum individual battery cell voltage includes the minimum voltage among the voltages of the individual battery cells. Specifically, the BMS calculates the maximum and minimum individual battery cell voltages through the formula "Actual voltage of the battery pack = (Maximum individual battery cell voltage + Minimum individual battery cell voltage) / 2" to generate the actual voltage of the battery pack.

[0070] Step 1023b: Calculate the capacity step and the actual voltage of the battery pack according to the heat dissipation formula to generate the second heat dissipation.

[0071] In this step, the second heat dissipation includes the heat dissipation per unit time corresponding to capacity equalization. The heat dissipation formula includes:

[0072]

[0073] where Q 2 represents the second heat dissipation, △q represents the capacity step, and U represents the actual voltage of the battery pack.

[0074] Step 1024b: Calculate the second heat dissipation, the specific heat capacity of the slave board, and the mass of the slave board according to the specific heat capacity formula to generate the second temperature rise.

[0075] In this step, the second temperature rise includes the temperature rise per unit time corresponding to capacity equalization. The specific heat capacity formula includes:

[0076] Q 2 = CM△T 2

[0077] where Q 2 represents the second heat dissipation, C represents the specific heat capacity of the slave board, M represents the mass of the slave board, and △T 2 represents the second temperature rise.

[0078] Step 103: Generate the cumulative temperature rise based on the temperature rise per unit time and the detected equalization time.

[0079] As an optional solution, the equalization method includes voltage equalization, the temperature rise per unit time includes the first temperature rise, and the BMS multiplies the first temperature rise by the equalization time to generate the cumulative temperature rise. Specifically, the equalization time of the battery pack includes the equalization time of the battery pack detected by the BMS when the vehicle is powered on.

[0080] As another alternative, the balancing method includes capacity balancing, the temperature rise per unit time includes a second temperature rise, and the BMS multiplies the second temperature rise by the balancing time to generate an accumulated temperature rise. Specifically, the BMS detects the balancing time of the battery pack in real time, and there is a time difference of milliseconds between the obtained multiple balancing times. In the embodiments of the present invention, for the convenience of calculation, the balancing time of the battery pack detected by the BMS when the vehicle is powered on is used as the balancing time of the battery pack here.

[0081] Step 104: Generate a temperature difference according to the detected temperature parameters.

[0082] In this step, the temperature parameters include the ambient temperature, the upper limit of the temperature at which the chip can be used, and the temperature rise corresponding to the minimum number of heat dissipation channels. Specifically, the BMS adds the detected ambient temperature to the temperature rise corresponding to the minimum number of heat dissipation channels to generate a temperature sum value; subtracts the temperature sum value from the upper limit of the temperature at which the chip can be used to generate a temperature difference. Among them, the BMS calculates the heat dissipation corresponding to the minimum number of heat dissipation channels, the minimum number of heat dissipation channels, the capacity to be balanced, the maximum single-cell battery voltage, and the minimum single-cell battery voltage through the formula "heat dissipation corresponding to the minimum number of heat dissipation channels = minimum number of heat dissipation channels * capacity to be balanced * (maximum single-cell battery voltage + minimum single-cell battery voltage) / 2", generates the heat dissipation corresponding to the minimum number of heat dissipation channels, and then calculates the heat dissipation corresponding to the minimum number of heat dissipation channels, the specific heat capacity of the daughter board, and the mass of the daughter board according to the formula "temperature rise corresponding to the minimum number of heat dissipation channels = heat dissipation corresponding to the minimum number of heat dissipation channels / (specific heat capacity of the daughter board * mass of the daughter board)" to generate the temperature rise corresponding to the minimum number of heat dissipation channels.

[0083] Step 105: Determine the change amount of the heat dissipation channels according to the ratio of the temperature difference to the accumulated temperature rise.

[0084] In this step, the change amount of the heat dissipation channels includes the number of additional heat dissipation channels on the basis of the minimum number of heat dissipation channels. The change amount of the heat dissipation channels is a positive integer. The heat dissipation channels include balancing resistors and channel switches, and the BMS controls the opening or closing of the channel switches to control the opening or closing of the heat dissipation channels. In the embodiments of the present invention, in actual use, the change amount of the heat dissipation channels can be slightly adjusted according to the actual situation to make the battery pack safer. For example, the change amount of the heat dissipation channels can be appropriately subtracted by 1 or 2.

[0085] Step 106: Control the opening of the heat dissipation channels corresponding to the change amount of the heat dissipation channels according to the change amount of the heat dissipation channels.

[0086] In this step, the BMS controls the opening of the channel switches corresponding to the change amount of the heat dissipation channels, thereby controlling the opening of the heat dissipation channels corresponding to the channel switches. For example, if the minimum number of heat dissipation channels is 3 and the change amount of the heat dissipation channels is 4, and the BMS controls the opening of 4 channel switches, then the 4 heat dissipation channels corresponding to the 4 channel switches are opened, and at this time, a total of 7 heat dissipation channels are in the open state.

[0087] Step 107: Balance the battery pack according to the heat dissipation channels corresponding to the minimum number of heat dissipation channels and the heat dissipation channels corresponding to the change amount of the heat dissipation channels.

[0088] In this step, the BMS dissipates heat from the battery pack through the heat dissipation channels corresponding to the minimum number of heat dissipation channels and the heat dissipation channels corresponding to the change amount of the heat dissipation channels, balances the battery pack, and improves the imbalance phenomenon of the battery pack.

[0089] In the technical solution of the battery pack balancing method provided by the embodiments of the present invention, the specified battery pack parameters are calculated according to the heat dissipation formula and the specific heat capacity formula to generate the temperature rise per unit time corresponding to the balancing method; the cumulative temperature rise is generated according to the temperature rise per unit time and the detected balancing time; the temperature difference is generated by calculating the detected temperature parameters according to the preset relationship; the change amount of the heat dissipation channels is determined according to the ratio of the temperature difference to the cumulative temperature rise; and the battery pack is balanced according to the change amount of the heat dissipation channels. The battery management system flexibly opens the heat dissipation channels within the upper limit of the available temperature of the chip, improves the balancing efficiency, and solves the problem of low utilization rate of the heat dissipation channels caused by the fixed number of opened heat dissipation channels.

[0090] Figure 2 FIG. is a schematic structural diagram of a battery pack balancing device provided by an embodiment of the present invention, as Figure 2 shown. The device includes: a first generation module 11, a second generation module 12, a third generation module 13, a determination module 14, and a balancing module 15. The first generation module 11 is connected to the second generation module 12, the second generation module 12 is connected to the determination module 14, the third generation module 13 is connected to the determination module 14, and the determination module 14 is connected to the balancing module 15.

[0091] The first generation module 11 is configured to calculate the specified battery pack parameters according to the heat dissipation formula and the specific heat capacity formula to generate the temperature rise per unit time corresponding to the balancing method; the second generation module 12 is configured to generate the cumulative temperature rise according to the temperature rise per unit time and the detected balancing time; the third generation module 13 is configured to generate the temperature difference according to the detected temperature parameters; the determination module 14 is configured to determine the change amount of the heat dissipation channels according to the ratio of the temperature difference to the cumulative temperature rise; and the balancing module 15 is configured to balance the battery pack according to the change amount of the heat dissipation channels.

[0092] In the embodiment of the present invention, the balancing module 15 is specifically configured to control the opening of the heat dissipation channels corresponding to the heat dissipation channel change amount according to the heat dissipation channel change amount; and balance the battery pack according to the heat dissipation channels corresponding to the set minimum number of heat dissipation channels and the heat dissipation channels corresponding to the heat dissipation channel change amount.

[0093] In the embodiment of the present invention, the first generation module 11 is specifically configured to set a voltage step according to the heat dissipation capacity of the battery pack and the high-temperature bearing capacity of the battery pack; calculate the voltage step and the resistance value of the balancing resistor according to the heat dissipation formula to generate a first heat dissipation amount, where the first heat dissipation amount includes the heat dissipation amount per unit time corresponding to voltage balancing; calculate the first heat dissipation amount, the specific heat capacity of the slave board, and the mass of the slave board according to the specific heat capacity formula to generate a first temperature rise, where the first temperature rise includes the temperature rise per unit time corresponding to voltage balancing.

[0094] In the embodiment of the present invention, the first generation module 11 is specifically further configured to set a capacity step according to the heat dissipation capacity of the battery pack and the high-temperature bearing capacity of the battery pack; generate the actual voltage of the battery pack according to the voltages of the individual cells in the battery pack detected; calculate the capacity step and the actual voltage of the battery pack according to the heat dissipation formula to generate a second heat dissipation amount, where the second heat dissipation amount includes the heat dissipation amount per unit time corresponding to capacity balancing; calculate the second heat dissipation amount, the specific heat capacity of the slave board, and the mass of the slave board according to the specific heat capacity formula to generate a second temperature rise, where the second temperature rise includes the temperature rise per unit time corresponding to capacity balancing.

[0095] In the embodiment of the present invention, the second generation module 12 is specifically configured to multiply the first temperature rise by the balancing time to generate an accumulated temperature rise.

[0096] In the embodiment of the present invention, the second generation module 12 is specifically further configured to multiply the second temperature rise by the balancing time to generate an accumulated temperature rise.

[0097] In the embodiment of the present invention, the third generation module 13 is specifically configured to add the ambient temperature to the temperature rise corresponding to the minimum number of heat dissipation channels to generate a temperature sum value; subtract the temperature sum value from the upper limit of the temperature at which the chip can be used to generate a temperature difference.

[0098] In the technical solution of the battery pack balancing device provided in the embodiment of the present invention, the specified battery pack parameters are calculated according to the heat dissipation formula and the specific heat capacity formula to generate the temperature rise per unit time corresponding to the balancing method; the accumulated temperature rise is generated according to the temperature rise per unit time and the detected balancing time; the detected temperature parameters are calculated according to the preset relationship to generate a temperature difference; the heat dissipation channel change amount is determined according to the ratio of the temperature difference to the accumulated temperature rise; and the battery pack is balanced according to the heat dissipation channel change amount. The battery management system flexibly opens the heat dissipation channels within the upper limit of the temperature at which the chip can be used, improving the balancing efficiency and solving the problem of low utilization rate of the heat dissipation channels caused by the fixed number of opened heat dissipation channels.

[0099] An embodiment of the present invention provides a computer-readable storage medium, which includes a stored program. When the program runs, it controls the device where the computer-readable storage medium is located to execute the embodiment of the above-mentioned battery pack equalization method.

[0100] Figure 3 FIG. 5 is a schematic diagram of a battery management system provided by an embodiment of the present invention, including: The battery management system 3 of this embodiment includes: a processor 31, a memory 32, and a computer program 33 stored in the memory 32 and executable on the processor 31. When the computer program 33 is executed by the processor 31, it implements the battery pack equalization method in the embodiment. To avoid repetition, it will not be elaborated here one by one.

[0101] The battery management system 3 includes, but is not limited to, a processor 31 and a memory 32. Those skilled in the art can understand that Figure 3 This is only an example of the battery management system 3 and does not constitute a limitation on the battery management system 3. It may include more or fewer components than shown in the figure, or combine certain components, or different components. For example, the network device may also include input / output devices, network access devices, buses, etc.

[0102] The so-called processor 31 may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0103] The memory 32 may be an internal storage unit of the battery management system 3, such as the hard disk or memory of the battery management system 3. The memory 32 may also be an external storage device of the battery management system 3, such as a plug-in hard disk equipped on the battery management system 3, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. Further, the memory 32 may also include both an internal storage unit and an external storage device of the battery management system 3. The memory 32 is used to store computer programs and other programs and data required by the network device. The memory 32 may also be used to temporarily store data that has been output or will be output.

[0104] Those skilled in the art can clearly understand that for the convenience and conciseness of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated herein.

[0105] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0106] Any process or method description in a flowchart or described in other ways herein can be understood to represent a module, segment, or part of code including one or more executable instructions for implementing a customized logical function or process, and the scope of the preferred embodiments of the present invention includes additional implementations, where the functions can be executed in a manner not shown or discussed, including in a substantially simultaneous manner according to the involved functions or in a reverse order, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0107] Depending on the context, the word "if" as used herein can be interpreted as "when" or "while" or "in response to determining" or "in response to detecting". Similarly, depending on the context, the phrase "if determined" or "if detecting (stated condition or event)" can be interpreted as "when determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)".

[0108] In several embodiments provided by the present invention, it should be understood that the disclosed systems and methods can be implemented in other ways. For example, the system embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there can be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection between each other can be through some interfaces, and the indirect coupling or communication connection of devices or units can be in electrical, mechanical, or other forms.

[0109] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. An equalization method for a battery pack, characterized in that, the method is applied to a battery management system BMS, and the method includes: Calculating the heat dissipation per unit time, the specific heat capacity, and the mass of the slave board corresponding to the equalization method according to the specific heat capacity formula to generate the temperature rise per unit time of the slave board corresponding to the equalization method, and the heat dissipation per unit time of the slave board is calculated according to the heat dissipation formula for specified battery pack parameters; Generating a cumulative temperature rise according to the temperature rise per unit time of the slave board and the detected equalization time; Generating a temperature difference according to the detected temperature parameters; Determining the change amount of the heat dissipation channel according to the ratio of the temperature difference to the cumulative temperature rise; Equalizing the battery pack according to the change amount of the heat dissipation channel; The temperature parameters include the ambient temperature, the upper limit of the usable temperature of the chip, and the temperature rise corresponding to the minimum number of heat dissipation channels; The generating a temperature difference according to the detected temperature parameters includes: Adding the ambient temperature and the temperature rise corresponding to the minimum number of heat dissipation channels to generate a temperature sum value; Subtracting the upper limit of the usable temperature of the chip from the temperature sum value to generate a temperature difference.

2. The method according to claim 1, characterized in that, the equalizing the battery pack according to the change amount of the heat dissipation channel includes: Controlling the opening of the heat dissipation channel corresponding to the change amount of the heat dissipation channel according to the change amount of the heat dissipation channel; Equalizing the battery pack according to the heat dissipation channel corresponding to the set minimum number of heat dissipation channels and the heat dissipation channel corresponding to the change amount of the heat dissipation channel.

3. The method according to claim 1, characterized in that, the equalization method includes voltage equalization, and the temperature rise per unit time of the slave board includes a first temperature rise, and the first temperature rise is used to characterize the temperature rise per unit time of the slave board corresponding to voltage equalization; The heat dissipation per unit time of the slave board includes a first heat dissipation, and the first heat dissipation is used to characterize the heat dissipation per unit time of the slave board corresponding to voltage equalization; the specified battery pack parameters include a voltage step and an equalization resistance value; The calculation of the first heat dissipation includes: Setting the voltage step according to the heat dissipation capacity of the battery pack and the high-temperature bearing capacity of the battery pack; Calculating the voltage step and the equalization resistance value according to the heat dissipation formula to generate the first heat dissipation; The calculating the heat dissipation per unit time, the specific heat capacity, and the mass of the slave board corresponding to the equalization method according to the specific heat capacity formula to generate the temperature rise per unit time of the slave board corresponding to the equalization method includes: Calculating the first heat dissipation, the specific heat capacity of the slave board, and the mass of the slave board according to the specific heat capacity formula to generate the first temperature rise.

4. The method according to claim 1, characterized in that, the equalization method includes capacity equalization, and the temperature rise per unit time of the slave board includes a second temperature rise, and the second temperature rise is used to characterize the temperature rise per unit time of the slave board corresponding to capacity equalization; The heat dissipation of the slave board per unit time includes a second heat dissipation amount, and the second heat dissipation amount is used to characterize the heat dissipation of the slave board corresponding to capacity balancing per unit time; the specified battery pack parameters include a capacity step and the actual voltage of the battery pack; The calculation of the second heat dissipation amount includes: Setting the capacity step according to the heat dissipation capacity of the battery pack and the high-temperature bearing capacity of the battery pack; Generating the actual voltage of the battery pack according to the voltages of the individual cells in the battery pack detected; Calculating the capacity step and the actual voltage of the battery pack according to the heat dissipation formula to generate the second heat dissipation amount; The calculating, according to the specific heat capacity formula, the temperature rise per unit time of the slave board corresponding to the balancing method, the specific heat capacity of the slave board, and the mass of the slave board to generate the temperature rise per unit time of the slave board corresponding to the balancing method includes: Calculating the second heat dissipation amount, the specific heat capacity of the slave board, and the mass of the slave board according to the specific heat capacity formula to generate the second temperature rise.

5. The method according to claim 3, characterized in that the generating the cumulative temperature rise according to the temperature rise per unit time of the slave board and the detected balancing time includes: Multiplying the first temperature rise by the balancing time to generate the cumulative temperature rise.

6. The method according to claim 4, characterized in that the generating the cumulative temperature rise according to the temperature rise per unit time of the slave board and the detected balancing time includes: Multiplying the second temperature rise by the balancing time to generate the cumulative temperature rise.

7. An equalization device for a battery pack, characterized in that the device includes: A first generation module, configured to calculate, according to the specific heat capacity formula, the heat dissipation per unit time of the slave board corresponding to the balancing method, the specific heat capacity of the slave board, and the mass of the slave board, to generate the temperature rise per unit time of the slave board corresponding to the balancing method, and the heat dissipation per unit time of the slave board is obtained by calculating the specified battery pack parameters according to the heat dissipation formula; A second generation module, configured to generate a cumulative temperature rise according to the temperature rise per unit time of the slave board and the detected balancing time; A third generation module, configured to generate a temperature difference according to the detected temperature parameters; A determination module, configured to determine a heat dissipation channel change amount according to a ratio of the temperature difference to the cumulative temperature rise; An equalization module, configured to equalize the battery pack according to the heat dissipation channel change amount; The temperature parameters include the ambient temperature, the upper limit of the usable temperature of the chip, and the temperature rise corresponding to the minimum number of heat dissipation channels; The third generation module is further configured to: add the ambient temperature to the temperature rise corresponding to the minimum number of heat dissipation channels to generate a temperature sum value; subtract the temperature sum value from the upper limit of the usable temperature of the chip to generate a temperature difference.

8. A battery management system, characterized in that it includes: One or more processors; A memory; And one or more computer programs, wherein the one or more computer programs are stored in the memory, and the one or more computer programs include instructions that, when executed by the battery management system, cause the battery management system to execute the method according to any one of claims 1 to 6.

9. A computer-readable storage medium, It is characterized in that the computer-readable storage medium includes a stored program, wherein when the program runs, it controls the device where the computer-readable storage medium is located to execute the method according to any one of claims 1 to 6.

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