CN110880622A - Equalization control method of battery pack - Google Patents

Equalization control method of battery pack Download PDF

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Publication number
CN110880622A
CN110880622A CN201910979954.4A CN201910979954A CN110880622A CN 110880622 A CN110880622 A CN 110880622A CN 201910979954 A CN201910979954 A CN 201910979954A CN 110880622 A CN110880622 A CN 110880622A
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equalization
time
voltage
submodule
battery
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吴凯
苏连旺
程睿
梁明华
郑礼生
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Jiangxi Hengdong New Energy Co Ltd
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Jiangxi Hengdong New Energy Co Ltd
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/4207—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells for several batteries or cells simultaneously or sequentially
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
    • H01M10/4257—Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/44—Methods for charging or discharging
    • H01M10/441—Methods for charging or discharging for several batteries or cells simultaneously or sequentially
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0013—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
    • H02J7/0014—Circuits for equalisation of charge between batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
    • H01M2010/4271—Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
    • H01M2010/4278—Systems for data transfer from batteries, e.g. transfer of battery parameters to a controller, data transferred between battery controller and main controller
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

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  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Charge And Discharge Circuits For Batteries Or The Like (AREA)
  • Secondary Cells (AREA)

Abstract

The invention discloses a battery pack equalization control method, which controls the equalization of a battery pack through a preprocessing module, an equalization information calculation module based on a charge state, an equalization information calculation module based on a charge terminal voltage and an equalization opening and closing control module. The invention has the advantages that: the balance control strategy takes the voltage and the battery charge state as balance variables, the voltage is taken as the balance variables, the voltage can be directly measured, the operation is simple, the response speed is high, and the voltage has large fluctuation in the working state, so the voltage can not comprehensively measure the battery consistency. Meanwhile, the battery charge state is used as a battery equalization variable, so that the batteries can keep consistent in dischargeable electric quantity, the energy utilization rate of the batteries can be improved better, equalization is allowed to be started when charging is started, and the equalization efficiency is improved.

Description

Equalization control method of battery pack
Technical Field
The invention relates to a balance control method of a battery pack, and belongs to the technical field of battery balance.
Background
When the lithium battery is used in the fields of electric vehicles, energy storage systems and the like, the lithium battery is limited by the voltage and the capacity of the single battery, and the battery pack is formed by corresponding series-parallel connection to improve the total voltage and the total capacity. The inconsistency of each single battery in the battery pack is necessarily caused by the following two reasons: 1 inconsistencies resulting from the manufacturing process of the cell: this mainly refers to the innate part of the battery inconsistency. As a chemical product, the battery has certain inconsistency when leaving a factory due to the restriction of materials, processes and other factors. For example, different batches of battery raw materials may result in certain inconsistencies in the chemical properties of the battery materials; for another example, even if raw materials of the same batch are ground and stirred, inconsistency of particle size, conductivity and the like of the electrode material may occur; for another example, during formation of a battery, the SEI film formed near the electrode has a certain randomness, which also causes inconsistency of the battery. These inconsistencies may manifest themselves in various aspects of battery performance: on the one hand, the battery capacities do not coincide, and on the other hand, the self-discharge coefficients of the batteries do not coincide. 2 operating environment of the cell leading to inconsistencies: this refers primarily to the acquired part of the battery inconsistency. The performance of the battery is greatly influenced by the working environment, and factors influencing the performance of the battery comprise temperature, vibration and the like, wherein the temperature is an important factor influencing the inconsistency of the power battery. The temperature field distribution in the battery pack is difficult to be uniform, and in short, the effective capacity and the charge-discharge performance of the single battery are possibly inconsistent due to the non-uniform temperature field; in the long term, such non-uniformity may lead to inconsistent degradation of the cell chemistry, i.e., inconsistent aging of each cell.
In the use process of the battery pack, for safety reasons, the battery management system takes the battery with the lowest voltage as the standard for forbidding discharge when the battery is lower than the discharge overvoltage protection threshold, and takes the battery with the highest voltage as the standard for forbidding charge when the battery is higher than the charge overvoltage protection threshold. When charging, the individual single battery reaches the charging cut-off voltage first to complete charging, and when discharging, the individual single battery reaches the discharging cut-off voltage first to stop discharging, thereby greatly reducing the available energy of the battery pack. And as the number of charging and discharging times is increased, the voltage difference between the batteries is larger and larger, and the electric quantity which can be effectively used by the battery pack is smaller and smaller.
In order to avoid the uniformity deterioration of the batteries, a common solution is to design an equalization circuit inside the battery pack, and the equalization circuit is used to control each single battery to be equalized to be uniform when the single batteries are not uniform. At present, equalizing circuits can be classified according to different modes, 1 is classified according to the working state of a battery pack, and can be divided into charging equalization, namely the equalization is started in the charging process of a battery, and discharging equalization, namely the equalization is started in the discharging process of the battery, and bidirectional equalization is started in the whole charging and discharging process. And 2, classifying according to the initiative of equalization, and classifying into active equalization and passive equalization, wherein the active equalization is that an equalization device can automatically and actively start equalization operation according to the state of the battery pack, and the passive equalization can not actively judge the state of the battery pack and only passively start equalization operation. The 3 is classified according to energy mode, and can be divided into energy dissipation type and energy non-dissipation type, namely, a passive equalization mode and an active equalization mode. The active equalization mainly comprises an energy storage element, a switching element, a diode and the like, the energy with high cell energy is transferred to the cell with low energy, and the mode can not cause the energy loss of the battery, but the active equalization circuit is complex, the integration level is not high, the stability is low and the cost is high. The passive balance is formed by a switch element and a dissipation resistor, the energy of a high-energy battery core is released through a parallel resistor, the energy of the battery is consumed in the mode, the utilization rate of the battery is reduced, and the implementation mode is simple and reliable and high in integration level.
In the method, the voltage of the battery cell can be directly measured, so that the voltage-based equalization is most easily realized and is generally adopted. This method is intended to discharge a battery cell or a battery string having a relatively high voltage by using an equalizing resistor and a switch when a battery system is in a charged or stationary state. In the method, the voltage trend of each single battery or battery pack string in the same battery system is always the same as the balancing target, so that the voltage of the single battery or battery pack string is used as a main judgment basis to judge whether the single battery needs to be balanced.
In practical use, the disadvantages of cell voltage equalization mainly include: 1 if only the charge termination voltage is aligned, the equalization can be turned on for a very short time and the equalization efficiency is low because the state is now close to full. The terminal voltage of the single battery can be approximately calculated as
Vt＝Vocv+I*Rdc
(Vt represents terminal voltage; Vocv is open-circuit voltage of the battery monomer in the current state; I is charge-discharge current, the charge is positive value, the discharge is negative value; Rdc is direct-current internal resistance of the battery monomer or the battery pack string); this means that if the direct-current internal resistances of the battery cells are different, the terminal voltage of the battery cell or the battery string in actual use depends not only on the open-circuit voltage Vocv but also on the direct-current internal resistance Rdc and the charge-discharge current I, which also means that the battery cell having a higher voltage in the charged state may not have a higher voltage in the rest state because of the presence of the charge current I and the internal resistance Rdc of the battery cell; moreover, even in the same charge-discharge cycle, the direct current internal resistance Rdc of the battery cell is not a fixed value, and in the same cycle, the direct current internal resistance Rdc of the same battery cell at different SOCs is also different, and the direct current internal resistance of the battery cell is not taken into account based on the balancing of the voltage of the battery cell, so that the probability of misjudging the balancing is increased. Therefore, if only the voltage value is considered but the difference in the charge amount of each unit cell is not considered when the equalization information is calculated, the equalization information may be calculated inaccurately.
Disclosure of Invention
The present invention provides a method for controlling equalization of a battery pack.
The invention is realized by the following scheme: the battery pack equalization control method controls the equalization of a battery pack through a preprocessing module, an equalization information calculation module based on a charge state, an equalization information calculation module based on a charge terminal voltage and an equalization opening and closing control module.
The pretreatment module consists of a current treatment submodule, a temperature treatment submodule and a long-time standing judgment submodule.
And the long-time standing judgment submodule judges whether the time of subtracting the time of the real-time clock at the last power-off time from the time of the real-time clock at the power-on time is greater than the SOC static correction time threshold value or not within a certain time before the system is powered on again, if so, the long-time standing judgment submodule judges that the flag bit is set, and if not, the flag bit is cleared.
The charge state-based equalization information calculation module consists of five submodules, namely an equalization information calculation function enabling judgment submodule, an equalization time matrix calculation submodule, a residual time submodule for updating equalization during equalization, a battery cell sequence and time submodule for outputting battery cell sequences and time required to be stored in a power-off mode, and a battery cell serial number submodule for calculating the longest equalization time.
The balance information calculation function enabling judgment submodule judges whether the absolute value of the monomer current is smaller than or equal to a small current threshold, whether the minimum temperature of the system is larger than or equal to the minimum temperature of an enabling OCV (open control voltage) table lookup, whether the maximum voltage of the system is smaller than or equal to an SOC (state of charge) correction low-end voltage threshold, whether a standing mark position is set for a long time, whether the four conditions are met, if so, the balance information calculation function enabling mark position is set, and if not, the balance information calculation function enabling mark position is cleared.
When the equalization information calculation function of the equalization time matrix calculation submodule is set, the input voltage signal group and the system minimum voltage are used for obtaining SOC difference values of all the input electric cores through table lookup, the electric cores of which the SOC difference values are larger than the overlarge SOC difference values are selected as the electric cores needing equalization, and the equalization time of the electric cores is calculated: calculating the required equalization time of the corresponding battery cell according to the following formula:
Figure BDA0002234872900000041
in the above formula,. DELTA.socIs the difference between the corresponding cell SOC and the lowest SOC, CnomIs the nominal capacity of the cell, NparaIs a number of cells connected in parallel, IbaiFor equalizing the current, TcallIs the scheduling period of the equalization module.
When the balance information calculation function enabling flag bit of the balance time submodule which updates balance in the balance process is in a set state, the updated calculated balance time matrix is the calculated balance time matrix, the cell serial number which needs to be updated is selected as the serial number of the cell with the voltage equal to the highest voltage in the next step, and if the balance information calculation function enabling flag bit is cleared, the updated calculated balance time matrix is the balance time matrix calculated in the next step; selecting the serial number of the electric core needing to be updated as the serial number of the initial electric core for electrifying or the serial number of the electric core which is started in balance last time; updating the equalization time matrix again: in a scheduling period, if the balance is started, subtracting a calling period from the balance residual time, and judging whether the voltage difference of the maximum and minimum voltages is less than the balance stopping voltage difference value, and clearing the balance time. And outputting the battery cell sequence and time submodule which need to be stored after power down, and storing the balance time of which the balance time is greater than the lower limit time value which needs to be stored in the balance time.
The sub-module for calculating the serial number of the battery cell with the longest balancing time subtracts the minimum value of the residual balancing time matrix to obtain a difference matrix of all balancing times, subtracts the minimum value of the maximum value of the residual balancing time matrix to obtain a maximum and minimum balancing time difference, the maximum and minimum balancing time difference is greater than a balancing opening time threshold, and finds the serial number of the battery cell with the longest residual balancing time: and finding out the electric core which is equal to the maximum and minimum balancing time difference from all the balancing time difference matrixes, and using the electric core as the electric core to be balanced, wherein the electric core is obtained by balancing calculation based on the SOC.
The charge tail end voltage-based equalization calculation module consists of a charge tail end judgment submodule and a cell serial number submodule needing to be equalized and calculated according to voltage, wherein the charge tail end judgment submodule sets a charge tail end flag bit if the highest voltage of a system is greater than a charge tail end voltage threshold, the cell serial number submodule needing to be equalized is calculated according to the voltage, the input voltage signal group subtracts the lowest voltage of the system to obtain all voltage difference matrixes, the lowest voltage of the system subtracts the highest voltage of the system to obtain a maximum and minimum voltage difference value, and if the maximum and minimum voltage difference value is greater than a starting equalization pressure difference value, the serial number of the cell serial number needing to be equalized is the serial number of the cell with the maximum voltage is calculated until the maximum and minimum voltage difference value is less than a stopping equalization.
The equalizing opening and closing control module consists of a sub-module for opening and closing the equalizing module at intervals. And after the upper limit time of the equalizing opening time is set every other, equalizing is opened and closed, whether the mark position of the charging tail end is set is judged, if so, the serial number of the battery cell needing equalizing is a calculated value based on the voltage of the charging tail end, and if not, the serial number of the battery cell needs equalizing is a calculated value based on the state of charge.
The invention has the beneficial effects that: the voltage and the battery charge state are used as balance variables of the balance control strategy, the voltage is used as the balance variable, the voltage can be directly measured, the operation is simple, the response speed is high, and the voltage has large fluctuation in the working state, so that the voltage can not comprehensively measure the battery consistency. Meanwhile, the battery charge state is used as a battery equalization variable, so that the batteries can keep consistent in dischargeable electric quantity, the energy utilization rate of the batteries can be improved better, equalization is allowed to be started when charging is started, and the equalization efficiency is improved.
Drawings
Fig. 1 is a schematic structural diagram of a method for controlling equalization of a battery pack according to the present invention.
Fig. 2 is a logic flow diagram of an equalization information calculation function enabling determination sub-module in the equalization control method of a battery pack according to the present invention.
Fig. 3 is a logic flow diagram of a remaining time submodule for updating equalization during equalization in the equalization control method of a battery pack according to the present invention.
Detailed Description
The invention will be further described with reference to fig. 1-3, without limiting the scope of the invention.
In the following description, for purposes of clarity, not all features of an actual implementation are described, well-known functions or constructions are not described in detail since they would obscure the invention with unnecessary detail, it being understood that in the development of any actual embodiment, numerous implementation details must be set forth in order to achieve the developer's specific goals, such as compliance with system-related and business-related constraints, changing from one implementation to another, and it being recognized that such development effort might be complex and time consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art.
Take passive equalization of lithium iron phosphate batteries as an example.
The method is realized by the following scheme: a battery pack equalization control method controls the equalization of a battery pack through a preprocessing module, an equalization information calculation module based on a charge state, an equalization information calculation module based on a charge terminal voltage and an equalization opening and closing control module.
The pretreatment module consists of a current treatment submodule, a temperature treatment submodule and a long-time standing judgment submodule.
Further, the long-time standing judgment submodule judges whether the difference value of the real-time clock RTC time at the power-on time minus the real-time clock RTC time at the last power-off time is larger than the SOC static correction time threshold value by 1 hour in the first 1S after the system is powered on again, sets the long-time standing flag bit if the difference value is larger than the SOC static correction time threshold value, and clears the long-time standing flag bit if the difference value is not larger than the SOC static correction time threshold value.
The charge state-based equalization information calculation module consists of an equalization information calculation function enabling judgment submodule and an equalization time matrix calculation submodule, wherein the equalization time matrix calculation submodule updates the equalized residual time submodule during equalization, outputs a battery cell sequence and a time submodule which need to be stored in a power-off mode, and calculates the battery cell serial number submodule with the longest equalization time.
Further, the logic flow of the equalization information calculation function enable determination submodule is as shown in fig. 2, the step S11 determines whether the absolute value of the cell current is less than or equal to a low current threshold 2A, if not, the equalization information calculation function enable flag is set to zero, if yes, the next step is performed, the step S12 determines whether the minimum temperature of the system is greater than or equal to the minimum temperature 10 degrees enabling OCV table lookup, if not, the equalization information calculation function enable flag is set to zero, if yes, the next step is performed, the step S13 determines whether the maximum voltage of the system is less than or equal to an SOC correction low-end voltage threshold 3.28V, if not, the equalization information calculation function enable flag is set to zero, if yes, the next step S14 determines whether the long-time standing flag is set, if not, the equalization information calculation function enable flag is set to zero, if so, the equalization information calculation function enable flag bit is set.
Further, a sub-module for calculating an equalization time matrix judges whether an enabling flag bit of an equalization information calculation function is set or not, if so, the voltage values and the lowest voltage values of all batteries are used for obtaining SOC values and the lowest SOC values of all batteries through an SOC-OCV data table lookup, the SOC values of all batteries minus the lowest SOC value are used for obtaining the SOC lowest difference value of all batteries, the battery with the SOC lowest difference value larger than 6% of the overlarge SOC difference value is selected as the battery needing equalization, and the time for starting equalization of the batteries is calculated, wherein the calculation formula is as follows: ,
Figure BDA0002234872900000071
in the above formula, CnomIs the nominal capacity (in Ah) of the battery, 90Ah, NparaIs the number of parallel cells, 2 and, DeltasocIs the difference value (in%) between the corresponding battery SOC and the lowest SOCbaiFor the equalizing current (in A), 0.05A, TcaliIs the scheduling period (unit is S) of the equalization module, 0.1S.
Further, when the remaining time submodule of equalization is updated during equalization, as shown in fig. 3, in step S21, if the equalization information calculation function enable flag bit is in a set state, the updated calculated equalization time matrix is the calculated equalization time matrix above, and then the serial number of the battery cell that needs to be updated is the serial number of the battery whose voltage is equal to the highest voltage. Step S22, if the balance information calculation function enables the zone bit reset state, the updated calculated balance time matrix is the balance time matrix calculated next, and then the battery cell serial number needing to be updated is selected as the initial battery cell for electrifying or the battery serial number which is balanced last time when being started. Step S23, the equalization time matrix is updated again: and (4) judging in a scheduling period, if the balance is started, subtracting a calling period from the balance residual time by 0.1S, and in step 24, judging that the balance time is cleared if the differential pressure of the maximum and minimum voltage is less than the stop balance differential pressure value by 15 mV.
Further, outputting the battery cell sequence and the time submodule which need to be powered down for storage, and storing the balance time of which the balance time is greater than the lower limit of the balance time which needs to be stored by 0.5 hour, wherein the number of the balance time is 5.
Further, calculating the cell serial number submodule with the longest balancing time, subtracting the minimum value from the residual balancing time matrix to obtain all balancing time difference value matrixes, subtracting the minimum value from the maximum value of the residual balancing time matrix to obtain the maximum and minimum balancing time difference value, wherein the maximum and minimum balancing time difference value is greater than the balancing opening time threshold value for 30 minutes, and finding the cell serial number with the longest residual balancing time: and finding out the electric core which is equal to the maximum and minimum balancing time difference from all the balancing time difference matrixes, and using the electric core as the electric core to be balanced, wherein the electric core is obtained by balancing calculation based on the SOC.
The charge terminal voltage-based equalization calculation module consists of a charge terminal judgment submodule and a battery cell serial number submodule for calculating the battery cell serial number to be equalized according to the voltage.
Further, the charging end judgment submodule sets the charging end flag bit if the highest system voltage is greater than the charging end voltage threshold value by 3.6V.
And further, calculating a sub-module of the cell serial number required to be balanced according to the voltage, subtracting the lowest voltage of the system from the input voltage signal group to obtain all voltage difference matrixes, subtracting the lowest voltage of the system from the highest voltage of the system to obtain the maximum and minimum voltage difference value, and if the maximum and minimum voltage difference value is greater than the starting balanced voltage difference value by 20mV, taking the cell serial number required to be balanced as the serial number of the cell with the maximum voltage until the maximum and minimum voltage difference value is less than the stopping balanced voltage difference value by 15 mV.
The equalization opening and closing control module is formed by opening and closing the equalization submodule at intervals. And after the upper limit time of the equalizing opening time is 0.5H, equalizing is opened and closed, whether the flag bit is set at the charging tail end is judged, if so, the serial number of the battery cell needing equalizing is a calculated value based on the voltage of the charging tail end, and otherwise, the serial number of the battery cell needs equalizing is a calculated value based on the state of charge.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A battery pack equalization control method is characterized in that: the battery pack balancing method is characterized in that the battery pack balancing is controlled by a preprocessing module, a charge state-based balancing information calculating module, a charging tail end voltage-based balancing information calculating module and a balancing opening and closing control module.
2. The method of claim 1, wherein: the pretreatment module consists of a current treatment submodule, a temperature treatment submodule and a long-time standing judgment submodule.
3. The equalization control method of a battery pack according to claim 2, wherein: and the long-time standing judgment submodule judges whether the time of subtracting the time of the real-time clock at the last power-off time from the time of the real-time clock at the power-on time is greater than the SOC static correction time threshold value or not within a certain time before the system is powered on again, if so, the long-time standing judgment submodule judges that the flag bit is set, and if not, the flag bit is cleared.
4. The method of claim 1, wherein: the charge state-based equalization information calculation module consists of five submodules, namely an equalization information calculation function enabling judgment submodule, an equalization time matrix calculation submodule, a residual time submodule for updating equalization during equalization, a battery cell sequence and time submodule for outputting battery cell sequences and time required to be stored in a power-off mode, and a battery cell serial number submodule for calculating the longest equalization time.
5. The method of claim 4, wherein: the balance information calculation function enabling judgment submodule judges whether the absolute value of the monomer current is smaller than or equal to a small current threshold value, whether the minimum temperature of the system is larger than or equal to the minimum temperature of an enabling OCV (open control voltage) table lookup, whether the maximum voltage of the system is smaller than or equal to an SOC (state of charge) correction low-end voltage threshold value, whether a standing mark position is set for a long time, judges whether the four conditions are met, if so, the balance information calculation function enabling mark position is set, and if not, the balance information calculation function enabling mark position is reset.
6. The method of claim 4, wherein: and when the equalization information calculation function enabling setting is performed by the equalization time matrix calculation submodule, the input voltage signal group and the system lowest voltage are used for obtaining SOC difference values input into all the battery cells through table lookup, the battery cells with the SOC difference values larger than the overlarge SOC difference values are selected as the battery cells needing equalization, and the equalization time of the battery cells is calculated.
7. The method of claim 4, wherein: and when the balance time remaining submodule for updating balance in the balance process is in a set state at the balance information calculation function enabling flag bit, the updated calculated balance time matrix is the calculated balance time matrix, the cell serial number to be updated is selected as the serial number of the cell with the voltage equal to the highest voltage, the cell sequence and the time submodule which need to be stored in a power-off state are output, and the balance time of which the balance time is greater than the lower limit time value which needs to be stored in the balance time is stored.
8. The method of claim 4, wherein: and the submodule for calculating the serial number of the battery cell with the longest equalization time subtracts the minimum value of the residual equalization time matrix to obtain a difference matrix of all equalization time, subtracts the maximum value of the residual equalization time matrix from the minimum value to obtain a maximum and minimum equalization time difference value, wherein the maximum and minimum equalization time difference value is greater than an equalization starting time threshold value, finds the serial number of the battery cell with the longest residual equalization time, finds the battery cell equal to the maximum and minimum equalization time difference value from all the equalization time difference value matrixes, and uses the battery cell to be equalized obtained by equalization calculation based on the SOC.
9. The method of claim 1, wherein: the charge tail end voltage-based equalization calculation module consists of a charge tail end judgment submodule and a battery cell sequence number submodule needing to be equalized according to voltage, the work flow of the charge tail end judgment submodule is that if the highest voltage of a system is greater than the voltage threshold of the charge tail end, the charge tail end is set at a mark position, the battery cell sequence number submodule needing to be equalized is calculated according to the voltage, the input voltage signal group subtracts the lowest voltage of the system to obtain all voltage difference matrixes, and the highest voltage of the system subtracts the lowest voltage of the system to obtain the maximum and minimum voltage difference value.
10. The method of claim 1, wherein: the equalization opening and closing control module is composed of a sub-module for opening and closing equalization at intervals, equalization is opened and closed after the upper limit time of the equalization opening time, whether the charging tail end flag bit is set or not is judged, if yes, the serial number of the battery cell needing equalization is a calculated value based on the voltage of the charging tail end, and if not, the serial number of the battery cell needing equalization is a calculated value based on the state of charge.
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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111864844A (en) * 2020-07-27 2020-10-30 中航锂电（洛阳）有限公司 Equalization method and equalization device of battery system and intelligent equipment
CN112133976A (en) * 2020-08-25 2020-12-25 合肥国轩高科动力能源有限公司 Battery pack module balancing method
CN112350400A (en) * 2020-10-30 2021-02-09 湖北工业大学 Lithium battery pack non-hierarchical active and passive equalization circuit and method
CN112782587A (en) * 2020-12-24 2021-05-11 金龙联合汽车工业（苏州）有限公司 Power battery monomer abnormal change detection method and system
CN113036845A (en) * 2021-03-05 2021-06-25 万向一二三股份公司 Battery pack balancing strategy based on available capacity of battery cell
WO2021217314A1 (en) * 2020-04-26 2021-11-04 深圳市大疆创新科技有限公司 Battery equalization method, intelligent battery, charging system and storage medium
CN113629810A (en) * 2021-08-10 2021-11-09 湖北亿纬动力有限公司 Battery management system matching method and device
CN114696425A (en) * 2022-04-29 2022-07-01 无锡锐祺通讯技术有限公司 Equalization method of lithium iron phosphate battery pack and battery equalization charging system

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104052087A (en) * 2013-03-13 2014-09-17 中国科学院沈阳自动化研究所 Intelligent lithium ion battery management system for electric vehicle and balance control method thereof
JP2016005288A (en) * 2014-06-13 2016-01-12 パナソニックＩｐマネジメント株式会社 Equalization processing device
CN106655408A (en) * 2017-02-06 2017-05-10 中航锂电（洛阳）有限公司 Balancing control method and control device of battery pack
CN107369858A (en) * 2017-08-02 2017-11-21 河南理工大学 A kind of battery pack Bi-objective equalizing circuit control strategy stage by stage
CN107839500A (en) * 2017-07-11 2018-03-27 苏州大学 A kind of dynamic corrections SOC lithium battery group balance control method and system
JP2018125977A (en) * 2017-02-01 2018-08-09 トヨタ自動車株式会社 Control apparatus of battery module
CN108539300A (en) * 2018-04-27 2018-09-14 上海蓝诺新能源技术有限公司 The electric quantity balancing method and system of battery pack
CN109017381A (en) * 2018-07-31 2018-12-18 电子科技大学 A kind of power battery pack composite balancing control method
CN109995102A (en) * 2019-03-01 2019-07-09 中国第一汽车股份有限公司 A kind of equal balance system of Prospect of EVS Powered with Batteries and control method
CN110071540A (en) * 2019-03-28 2019-07-30 江西恒动新能源有限公司 A kind of balance charging method of lithium-ions battery packet

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104052087A (en) * 2013-03-13 2014-09-17 中国科学院沈阳自动化研究所 Intelligent lithium ion battery management system for electric vehicle and balance control method thereof
JP2016005288A (en) * 2014-06-13 2016-01-12 パナソニックＩｐマネジメント株式会社 Equalization processing device
JP2018125977A (en) * 2017-02-01 2018-08-09 トヨタ自動車株式会社 Control apparatus of battery module
CN106655408A (en) * 2017-02-06 2017-05-10 中航锂电（洛阳）有限公司 Balancing control method and control device of battery pack
CN107839500A (en) * 2017-07-11 2018-03-27 苏州大学 A kind of dynamic corrections SOC lithium battery group balance control method and system
CN107369858A (en) * 2017-08-02 2017-11-21 河南理工大学 A kind of battery pack Bi-objective equalizing circuit control strategy stage by stage
CN108539300A (en) * 2018-04-27 2018-09-14 上海蓝诺新能源技术有限公司 The electric quantity balancing method and system of battery pack
CN109017381A (en) * 2018-07-31 2018-12-18 电子科技大学 A kind of power battery pack composite balancing control method
CN109995102A (en) * 2019-03-01 2019-07-09 中国第一汽车股份有限公司 A kind of equal balance system of Prospect of EVS Powered with Batteries and control method
CN110071540A (en) * 2019-03-28 2019-07-30 江西恒动新能源有限公司 A kind of balance charging method of lithium-ions battery packet

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
何忠霖等: "基于扩展卡尔曼滤波的车用锂离子电池SOC估算", 《汽车零部件》 *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021217314A1 (en) * 2020-04-26 2021-11-04 深圳市大疆创新科技有限公司 Battery equalization method, intelligent battery, charging system and storage medium
CN111864844A (en) * 2020-07-27 2020-10-30 中航锂电（洛阳）有限公司 Equalization method and equalization device of battery system and intelligent equipment
CN112133976A (en) * 2020-08-25 2020-12-25 合肥国轩高科动力能源有限公司 Battery pack module balancing method
CN112350400A (en) * 2020-10-30 2021-02-09 湖北工业大学 Lithium battery pack non-hierarchical active and passive equalization circuit and method
CN112782587A (en) * 2020-12-24 2021-05-11 金龙联合汽车工业（苏州）有限公司 Power battery monomer abnormal change detection method and system
CN112782587B (en) * 2020-12-24 2023-02-28 金龙联合汽车工业（苏州）有限公司 Power battery monomer abnormal change detection method and system
CN113036845A (en) * 2021-03-05 2021-06-25 万向一二三股份公司 Battery pack balancing strategy based on available capacity of battery cell
CN113629810A (en) * 2021-08-10 2021-11-09 湖北亿纬动力有限公司 Battery management system matching method and device
CN113629810B (en) * 2021-08-10 2023-09-01 湖北亿纬动力有限公司 Battery management system matching method and device
CN114696425A (en) * 2022-04-29 2022-07-01 无锡锐祺通讯技术有限公司 Equalization method of lithium iron phosphate battery pack and battery equalization charging system

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Application publication date: 20200313