A method, system, terminal and storage medium for estimating battery cell consistency difference

Abstract

The present invention discloses a method, system, terminal and storage medium for estimating cell consistency difference, belonging to the field of battery technology, respectively obtaining the average daily wake-up time of the vehicle, the average balancing current and the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, as well as the open circuit voltage, battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell to be balanced, respectively determining the basic capacity to be balanced and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced; respectively obtaining the historical cumulative balancing time, depolarization speed and the depolarization speed of the comparison cell in the database of each cell to be balanced, determining the historical cumulative balancing time coefficient and depolarization coefficient of each cell to be balanced; determining the capacity to be balanced of each cell to be balanced by the basic capacity to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient of each cell to be balanced. The present invention improves the accuracy of estimating cell consistency of the battery system.

Description

Technical Field

[0001] The invention discloses a method, system, terminal and storage medium for estimating consistency differences of electric cells, belonging to the technical field of batteries. Background Art

[0002] During the production and manufacturing process of lithium-ion batteries, due to the constraints of materials and process factors, there are certain inconsistencies when the batteries leave the factory. In addition, during the operation of power batteries, the inconsistency of the working environment will also have a greater impact on its inconsistency. In the short term, the uneven temperature field in the battery system may lead to inconsistent effective capacity and charge and discharge performance of single cells. In the long term, such unevenness will lead to inconsistent degradation of battery chemical properties, that is, the aging degree of each battery is inconsistent. Due to the "barrel effect" in battery performance, key performance indicators such as capacity and power will also decrease with the difference in single cell consistency, thereby affecting indicators such as the economy and power of the entire vehicle or energy storage system. Therefore, it is of great significance to accurately identify the inconsistency of battery cells, which can provide an important basis for balancing management and battery cell safety management.

[0003] According to the different ways of energy transfer, battery balancing methods can be divided into active balancing and passive balancing. The balancing method that uses resistors to dissipate the energy of cells with higher residual power is called passive balancing, and the balancing method that transfers the energy of cells with higher residual power to cells with lower residual power is called active balancing. Due to the poor reliability and high cost of active balancing and the high factory consistency of current cell products, almost all electric vehicles on the market currently use passive balancing solutions.

[0004] As high-voltage technology of 800V and above for electric vehicles and energy storage battery systems gradually advances, the number of battery strings has increased from about 100 in the previous 400V system to about 200, or even more. The possibility of consistency differences due to individual differences in batteries, temperature differences, and other reasons has also increased, which has led to increased difficulty in estimating cell consistency differences and safety management. Due to the "barrel effect" in battery performance, key performance indicators such as capacity and power will also decrease with differences in single-cell consistency, thereby affecting indicators such as the economy and power of the entire vehicle. Summary of the invention

[0005] In view of the defects of the prior art, the present invention proposes a method, system, terminal and storage medium for estimating the consistency difference of battery cells. By comprehensively considering factors such as the open circuit voltage of the battery, the battery health status, the self-discharge rate, the historical accumulated balancing time, the full depolarization speed, etc., the accuracy of the battery system cell consistency estimation is improved, and balancing is performed to avoid mis-balancing.

[0006] The technical solution of the present invention is as follows:

[0007] According to a first aspect of an embodiment of the present invention, a method for estimating cell consistency difference is provided, comprising:

[0008] The average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, as well as the open circuit voltage, battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell are obtained respectively, and the basic capacity to be balanced and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced are determined respectively;

[0009] The historical cumulative balancing time, depolarization speed and the depolarization speed of the comparison monomer in the database of each monomer to be balanced are obtained respectively, and the historical cumulative balancing time coefficient and depolarization coefficient of each monomer to be balanced are determined respectively according to the basic capacity to be balanced, the historical cumulative balancing time, the depolarization speed and the depolarization speed of the comparison monomer in the database of each monomer to be balanced;

[0010] The capacity to be balanced of each monomer to be balanced is determined by the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient. The passive balancing method is selected according to the capacity to be balanced of each monomer to be balanced to perform balanced discharge on each monomer to be balanced.

[0011] Preferably, the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, and the open circuit voltage, battery health status, battery rated capacity, and capacity error caused by voltage sampling error of each cell are obtained respectively, and the basic capacity to be balanced and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced are determined respectively, including:

[0012] The open circuit voltage, battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell are obtained respectively, and the basic capacity to be balanced of each cell to be balanced is determined;

[0013] The average daily wake-up time of the vehicle, the average balancing current, and the self-discharge rate difference between the lowest voltage cell and the cell to be balanced are obtained respectively; the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced is determined through the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, the battery health status of each cell to be balanced, the battery rated capacity and the basic capacity to be balanced.

[0014] Preferably, the open circuit voltage, battery health status and battery rated capacity of each cell are obtained respectively to determine the basic capacity to be balanced of each cell to be balanced, including:

[0015] Obtain the open circuit voltage of each cell respectively, and determine the charge data of each cell through the open circuit voltage and OCV-SOC table;

[0016] Get the battery rest time and determine whether it is greater than the preset rest time:

[0017] Yes, proceed to the next step;

[0018] No, the electrolyte distribution of each monomer is uneven, and the execution ends;

[0019] Determine the lowest voltage monomer charging data through each monomer charging data and open circuit voltage;

[0020] The difference between each monomer charge data and the lowest voltage monomer charge data is used to determine whether it is greater than the preset threshold:

[0021] Yes, the corresponding monomers are monomers to be balanced;

[0022] If not, the corresponding capacity to be balanced of each monomer is 0;

[0023] Obtain the battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell to be balanced and the cell with the lowest voltage respectively;

[0024] The basic capacity of each cell to be balanced is determined by the battery health status, the battery rated capacity and the capacity error caused by the voltage sampling error of each cell to be balanced and the cell with the lowest voltage.

[0025] Preferably, the capacity to be balanced caused by the self-discharge rate difference of each to-be-balanced cell is determined by the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the to-be-balanced cell, the battery health status of each to-be-balanced cell, the battery rated capacity of each cell and the basic to-be-balanced capacity, including:

[0026] Determine the self-discharge capacity difference of each to-be-balanced cell by the battery health status, the battery rated capacity and the self-discharge rate difference between the lowest voltage cell and the to-be-balanced cell;

[0027] The capacity to be balanced caused by the self-discharge rate difference of each to-be-balanced cell is determined by the average daily wake-up time of the vehicle, the average balancing current, the basic to-be-balanced capacity of each to-be-balanced cell, and the monthly self-discharge rate difference.

[0028] Preferably, the historical cumulative balancing time coefficient and the depolarization coefficient of each to-be-balanced monomer are determined respectively by the basic to-be-balanced capacity, the historical cumulative balancing time, the depolarization speed and the depolarization speed of the comparison monomer in the database, including:

[0029] Determine the average historical cumulative balancing time of all monomers to be balanced through the historical cumulative balancing time of each monomer to be balanced;

[0030] Determine the deviation ratio of the cumulative balancing time of each monomer to be balanced from the average value through the historical cumulative balancing time of each monomer to be balanced and the average historical cumulative balancing time of all monomers;

[0031] Determine the average capacity of all cells to be balanced by using the basic capacity of each cell to be balanced.

[0032] Determine the average deviation ratio of the current capacity to be balanced of each to-be-balanced cell through the basic capacity to be balanced of each to-be-balanced cell and the average capacity to be balanced of all to-be-balanced cells;

[0033] The historical cumulative balancing time coefficient of each to-be-balanced cell is determined by the ratio of the cumulative balancing time of each to-be-balanced cell to deviate from the average value and the ratio of the current to-be-balanced capacity to deviate from the average value;

[0034] The depolarization coefficient of each monomer to be balanced is determined by the depolarization speed of each monomer to be balanced and the depolarization speed of the comparison monomer in the database.

[0035] Preferably, the capacity to be balanced of each to-be-balanced monomer is determined by formula 1 through the basic capacity to be balanced of each to-be-balanced monomer, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient:

[0036] Q=Q selfdis +Q demand ×K1×K2 (1)

[0037] Where: Q is the capacity of each unit to be balanced, Q selfdis is the basic capacity of each unit to be balanced, Q demand is the capacity to be balanced caused by the difference in self-discharge rates of each to-be-balanced monomer, K1 is the historical cumulative balancing time coefficient of each to-be-balanced monomer, and K2 is the depolarization coefficient of each to-be-balanced monomer.

[0038] According to a second aspect of an embodiment of the present invention, a battery cell consistency difference estimation system is provided, comprising:

[0039] The preliminary estimation module is used to obtain the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, as well as the open circuit voltage of each cell, the battery health status, the battery rated capacity and the capacity error caused by the voltage sampling error, and respectively determine the basic capacity to be balanced and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced;

[0040] The coefficient estimation module is used to obtain the historical cumulative balancing time, depolarization speed and depolarization speed of the comparison monomer in the database of each monomer to be balanced, and determine the historical cumulative balancing time coefficient and depolarization coefficient of each monomer to be balanced according to the basic capacity to be balanced, the historical cumulative balancing time, the depolarization speed and the depolarization speed of the comparison monomer in the database of each monomer to be balanced;

[0041] The final estimation module is used to determine the capacity to be balanced of each monomer to be balanced through the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient, and select the passive balancing method to perform balanced discharge on each monomer to be balanced based on the capacity to be balanced of each monomer to be balanced.

[0042] Preferably, the final estimation module is used to:

[0043] The capacity to be balanced of each monomer to be balanced is determined by formula 1 through the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient:

[0044] Q=Q selfdis +Q demand ×K1×K2 (1)

[0045] Wherein: Q is the capacity to be balanced of each monomer to be balanced, Q selfdis is the basic capacity to be balanced of each monomer to be balanced, Q demand is the capacity to be balanced caused by the self-discharge rate difference of each monomer to be balanced, K1 is the historical cumulative balancing time coefficient of each monomer to be balanced, and K2 is the depolarization coefficient of each monomer to be balanced.

[0046] According to a third aspect of an embodiment of the present invention, a terminal is provided, including:

[0047] one or more processors;

[0048] a memory for storing the one or more processor-executable instructions;

[0049] Wherein, the one or more processors are configured to:

[0050] Execute the method described in the first aspect of the embodiment of the present invention.

[0051] According to a fourth aspect of an embodiment of the present invention, a non-temporary computer-readable storage medium is provided. When instructions in the storage medium are executed by a processor of a terminal, the terminal is enabled to execute the method described in the first aspect of the embodiment of the present invention.

[0052] According to a fifth aspect of the embodiments of the present invention, an application product is provided. When the application product is running on a terminal, the terminal executes the method described in the first aspect of the embodiments of the present invention.

[0053] The beneficial effects of the present invention are:

[0054] This patent provides a method, system, terminal and storage medium for estimating the consistency difference of battery cells, which comprehensively considers the consistency difference of battery cells in the future through the following dimensions, and then accurately estimates the capacity of battery cells to be balanced: (1) Identify the current capacity of different battery cells in the battery pack through the current open circuit voltage, temperature, battery health status, etc.; (2) Determine the capacity change of the battery cells in the future by identifying the self-discharge rate of the battery cells, which is used to calculate the capacity to be balanced caused by the self-discharge rate difference; (3) Determine the capacity difference of each battery cell before by the historical cumulative balancing time of the battery cells, which is used to correct the capacity to be balanced of the battery cells; (4) Identify the electrochemical characteristics of the battery cells through the depolarization of the battery after fast charging, especially the concentration polarization recovery state, and correct the capacity to be balanced of the battery cells.

[0055] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 is a flow chart of a method for estimating cell consistency differences according to an exemplary embodiment;

[0057] Figure 2 is a flow chart of a method for estimating cell consistency differences according to an exemplary embodiment;

[0058] Figure 3 is a flow chart of a method for estimating cell consistency differences according to an exemplary embodiment;

[0059] Figure 4 is a partial flow chart of a method for estimating cell consistency differences according to an exemplary embodiment;

[0060] Figure 5 is a partial flow chart of a method for estimating cell consistency differences according to an exemplary embodiment;

[0061] Figure 6 is a structural schematic block diagram of a battery cell consistency difference estimation system according to an exemplary embodiment;

[0062] Figure 7 The present invention is a schematic block diagram of a terminal structure according to an exemplary embodiment. DETAILED DESCRIPTION

[0063] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0064] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0065] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0066] An embodiment of the present invention provides a method for estimating battery cell consistency differences, which is implemented by a terminal. The terminal may be a smart phone, a desktop computer, or a laptop computer, etc. The terminal at least includes a CPU, a voice acquisition device, etc.

[0067] Embodiment 1

[0068] Figure 1 The present invention is a flow chart of a method for estimating cell consistency difference according to an exemplary embodiment. The method is used in a terminal, and the method includes the following steps:

[0069] Step 101, respectively obtain the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, as well as the open circuit voltage, battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell, and respectively determine the basic capacity to be balanced and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced;

[0070] Step 102, respectively obtaining the historical cumulative balancing time, depolarization speed and the comparison monomer depolarization speed in the database of each monomer to be balanced, and determining the historical cumulative balancing time coefficient and depolarization coefficient of each monomer to be balanced according to the basic capacity to be balanced, the historical cumulative balancing time, the depolarization speed and the comparison monomer depolarization speed in the database of each monomer to be balanced;

[0071] Step 103, determine the capacity to be balanced of each monomer to be balanced through the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient, and select a passive balancing method to perform balanced discharge on each monomer to be balanced based on the capacity to be balanced of each monomer to be balanced.

[0072] Preferably, the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, and the open circuit voltage, battery health status, battery rated capacity, and capacity error caused by voltage sampling error of each cell are obtained respectively, and the basic capacity to be balanced and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced are determined respectively, including:

[0073] The open circuit voltage, battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell are obtained respectively, and the basic capacity to be balanced of each cell to be balanced is determined;

[0074] The average daily wake-up time of the vehicle, the average balancing current, and the self-discharge rate difference between the lowest voltage cell and the cell to be balanced are obtained respectively; the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced is determined through the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, the battery health status of each cell to be balanced, the battery rated capacity and the basic capacity to be balanced.

[0075] Preferably, the open circuit voltage, battery health status and battery rated capacity of each cell are obtained respectively to determine the basic capacity to be balanced of each cell to be balanced, including:

[0076] Obtain the open circuit voltage of each cell respectively, and determine the charge data of each cell through the open circuit voltage and OCV-SOC table;

[0077] Get the battery rest time and determine whether it is greater than the preset rest time:

[0078] Yes, proceed to the next step;

[0079] No, the electrolyte distribution of each monomer is uneven, and the execution ends;

[0080] Determine the lowest voltage monomer charging data through each monomer charging data and open circuit voltage;

[0081] The difference between each monomer charge data and the lowest voltage monomer charge data is used to determine whether it is greater than the preset threshold:

[0082] Yes, the corresponding monomers are monomers to be balanced;

[0083] If not, the corresponding capacity to be balanced of each monomer is 0;

[0084] Obtain the battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell to be balanced and the cell with the lowest voltage respectively;

[0085] The basic capacity of each cell to be balanced is determined by the battery health status, the battery rated capacity and the capacity error caused by the voltage sampling error of each cell to be balanced and the cell with the lowest voltage.

[0086] Preferably, the capacity to be balanced caused by the self-discharge rate difference of each to-be-balanced cell is determined by the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the to-be-balanced cell, the battery health status of each to-be-balanced cell, the battery rated capacity of each cell and the basic to-be-balanced capacity, including:

[0087] Determine the self-discharge capacity difference of each to-be-balanced cell by the battery health status, the battery rated capacity and the self-discharge rate difference between the lowest voltage cell and the to-be-balanced cell;

[0088] The capacity to be balanced caused by the self-discharge rate difference of each to-be-balanced cell is determined by the average daily wake-up time of the vehicle, the average balancing current, the basic to-be-balanced capacity of each to-be-balanced cell, and the monthly self-discharge rate difference.

[0089] Preferably, the historical cumulative balancing time coefficient and the depolarization coefficient of each to-be-balanced monomer are determined respectively by the basic to-be-balanced capacity, the historical cumulative balancing time, the depolarization speed and the depolarization speed of the comparison monomer in the database, including:

[0090] Determine the average historical cumulative balancing time of all monomers to be balanced through the historical cumulative balancing time of each monomer to be balanced;

[0091] Determine the deviation ratio of the cumulative balancing time of each monomer to be balanced from the average value through the historical cumulative balancing time of each monomer to be balanced and the average historical cumulative balancing time of all monomers;

[0092] Determine the average capacity of all cells to be balanced by using the basic capacity of each cell to be balanced.

[0093] Determine the average deviation ratio of the current capacity to be balanced of each to-be-balanced cell through the basic capacity to be balanced of each to-be-balanced cell and the average capacity to be balanced of all to-be-balanced cells;

[0094] The historical cumulative balancing time coefficient of each to-be-balanced cell is determined by the ratio of the cumulative balancing time of each to-be-balanced cell to deviate from the average value and the ratio of the current to-be-balanced capacity to deviate from the average value;

[0095] The depolarization coefficient of each monomer to be balanced is determined by the depolarization speed of each monomer to be balanced and the depolarization speed of the comparison monomer in the database.

[0096] Preferably, the capacity to be balanced of each to-be-balanced monomer is determined by formula 1 through the basic capacity to be balanced of each to-be-balanced monomer, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient:

[0097] Q=Q selfdis +Q demand ×K1×K2 (1)

[0098] Where: Q is the capacity of each unit to be balanced, Q selfdis is the basic capacity of each unit to be balanced, Q demand is the capacity to be balanced caused by the difference in self-discharge rates of each to-be-balanced monomer, K1 is the historical cumulative balancing time coefficient of each to-be-balanced monomer, and K2 is the depolarization coefficient of each to-be-balanced monomer.

[0099] Embodiment 2

[0100] Figure 2-3 The present invention is a flow chart of a method for estimating cell consistency difference according to an exemplary embodiment. The method is used in a terminal, and the method includes the following steps:

[0101] Step 201, respectively obtain the open circuit voltage, battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell, and determine the basic capacity to be balanced of each cell to be balanced. The specific contents are as follows:

[0102] Obtain the open circuit voltage of each cell respectively, and determine the charge data of each cell through the open circuit voltage and OCV-SOC table;

[0103] Get the battery rest time and determine whether it is greater than the preset rest time:

[0104] If yes, it means that the monomer electrolyte is evenly distributed. The preset time depends on the characteristics of the monomer itself. The goal is to ensure that the battery electrolyte is evenly distributed, and then proceed to the next step;

[0105] No, the electrolyte distribution of each monomer is uneven, and the execution ends;

[0106] The lowest voltage single cell charging data is determined by each single cell charging data and the open circuit voltage, and the difference between each single cell charging data and the lowest voltage single cell charging data is respectively determined to determine whether it is greater than a preset threshold value, which is determined according to the charge and discharge characteristics of the single cell battery, with the goal of ensuring that the battery pack has a sufficiently high available capacity:

[0107] Yes, the corresponding monomers are monomers to be balanced;

[0108] If not, the corresponding capacity to be balanced of each monomer is 0;

[0109] Obtain the battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell to be balanced and the cell with the lowest voltage respectively;

[0110] The basic capacity of each cell to be balanced is determined by the battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell to be balanced and the cell with the lowest voltage. The specific contents are as follows:

[0111] The calculation formula for the capacity of each monomer to be balanced is:

[0112] The capacity of the single cell battery to be balanced = single cell battery charge data × battery health status × battery rated capacity.

[0113] The basic capacity to be balanced of each unit to be balanced is Q demand The calculation formula is:

[0114] Basic capacity to be balanced Q demand =Capacity of the single cell to be balanced - capacity of the single cell with the lowest voltage - capacity error caused by voltage sampling error.

[0115] Among them, the capacity of the lowest voltage single battery is the battery capacity corresponding to the lowest voltage single battery; the capacity error caused by the voltage sampling error is the battery capacity calculation error caused by the single battery voltage sampling error (for example, the single battery voltage sampling error is 10mV, the rated capacity of the battery single battery is 100AH, and the open circuit voltage difference corresponding to SOC 0% to SOC100% is 1000mV, then the capacity error caused by the voltage sampling error is 100AH*10mV*1000mV=1AH); therefore, the capacity error caused by the voltage sampling error is determined according to the single battery voltage sampling error and the charge and discharge characteristics of the single battery.

[0116] The following is an example based on the method described above:

[0117] Assume that there are 96 cells in the battery pack. After being fully rested for 2 hours, the electrolyte of the cells is evenly distributed. At this time, the BMS measures the voltage of the first cell to be 3.667V, the voltage of the second cell to be 3.692V, and the voltage of the remaining cells to be 3.67V. Through the OCV-SOC curve query, it is known that the SOC of the first cell is 50%, the SOC of the second cell is 55%, and the SOC of the remaining cells is 51%. It can be judged that the first cell is the lowest voltage cell at this time, the SOC difference between the second cell and the first cell is 5%, and the SOC difference between the remaining cells and the first cell is 1%. The preset threshold of the SOC difference of the cell to be balanced is 3%, so only the second cell is the cell to be balanced.

[0118] Assume that the health status of all 96 cells is 99%, the rated capacity is 150AH, and the capacity error caused by voltage sampling error is 1.2AH. It can be seen that the battery capacity of the second cell is 150AH*55%*99%, recorded as 81.68AH; the battery capacity of the first cell is 150AH*50%*99%, recorded as 74.25AH. Basic capacity to be balanced Q demand =Capacity of the single cell to be balanced - capacity of the single cell with the lowest voltage - capacity error caused by voltage sampling error = 81.68AH - 74.25AH - 1.2AH = 6.23AH.

[0119] Step 202, respectively obtain the average daily wake-up time of the vehicle, the average balancing current, and the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, and determine the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced according to the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, and the battery health status, battery rated capacity and basic capacity to be balanced of each cell to be balanced. The specific contents are as follows:

[0120] like Figure 4 As shown in the figure, when the electric vehicle is dormant, the battery can be equivalent to the static process. If the vehicle's dormant time exceeds the preset static time Tsleep, the BMS records the voltage of each monomer through self-wake-up, and then determines that the vehicle continues to dormant for more than 5 days (due to the limitation of BMS sampling accuracy, the monomer needs to be static for a sufficient time to have a significant capacity change):

[0121] If yes, proceed to the next step;

[0122] If not, the BMS records the voltage of each monomer by self-wake-up.

[0123] The starting and ending capacities of the cells can be calculated through the starting and ending open circuit voltages and OCV-SOC curves, the battery health status, and the rated capacity of the cells, and then the self-discharge rate △Q / △t of each cell can be calculated.

[0124] The self-discharge capacity difference of each to-be-balanced cell is determined by the following formula based on the battery health status, battery rated capacity, and the self-discharge rate difference between the lowest voltage cell and the to-be-balanced cell:

[0125] Self-discharge capacity difference Q diff =Battery rated capacity*battery health status*self-discharge rate difference between the lowest voltage cell and the cell to be balanced

[0126] Average daily wake-up time by vehicle T wakeup , average balancing current I avg And the basic capacity to be balanced Q of each unit to be balanced demand The self-discharge rate difference of each to-be-balanced monomer is used to determine the capacity Q to be balanced due to the self-discharge rate difference of each to-be-balanced monomer through formula 1. selfdis :

[0127] Q selfdis =Q diff ×Q demand / (T wakeup ×I avg ) (1)

[0128] The following is an example based on the method described above:

[0129] Assume that there are 96 cells in the battery pack, the battery health status is 99%, the rated capacity is 150AH, and the average daily wake-up time of the vehicle is T wakeup For 5 hours, the average balanced current I avg The current is 50mA, the monthly self-discharge rate difference between the lowest voltage monomer and the monomer to be balanced is 1%, and the monthly self-discharge capacity difference is Q diff =Battery rated capacity*battery health status*difference in self-discharge rate between the lowest voltage cell and the cell to be balanced=150AH*99%*1%=1.485AH; The basic capacity of the cell to be balanced Q calculated in the first step demand is 6.23AH, then:

[0130] The capacity to be balanced Q caused by the difference in self-discharge rate selfdis :

[0131] Q selfdis =Q diff ×Q demand / (T wakeup ×I avg )

[0132] =1.485AH×6.23AH / (5hour*0.05A*30day)=1.234AH

[0133] Step 203, respectively obtain the historical cumulative balancing time of each to-be-balanced monomer, and determine the historical cumulative balancing time coefficient of each to-be-balanced monomer according to the historical cumulative balancing time of each to-be-balanced monomer and the basic to-be-balanced capacity. The specific contents are as follows:

[0134] like Figure 5 As shown, the BMS counts the cumulative execution time of balancing of each cell, and stores it in the EEPROM after sleep, and reads it when it is powered on next time, and determines the average historical cumulative balancing time of all cells to be balanced through the historical cumulative balancing time of each cell to be balanced;

[0135] The historical cumulative balancing time of a single cell is proportional to the capacity of the single cell to be balanced. The longer the historical cumulative balancing time of a single cell, the longer the capacity to be balanced; the shorter the historical cumulative balancing time of a single cell, the shorter the capacity to be balanced. Define K1 as the historical cumulative balancing time coefficient of each single cell to be balanced, and:

[0136] The historical cumulative balancing time coefficient K1 of each to-be-balanced cell = the ratio of the cumulative balancing time of each to-be-balanced cell to deviate from the average value / the ratio of the current to-be-balanced capacity to deviate from the average value,

[0137] First, the deviation ratio of the cumulative balancing time of each monomer to be balanced from the average value is determined through the historical cumulative balancing time of each monomer to be balanced and the average historical cumulative balancing time of all monomers;

[0138] The ratio of cumulative equilibrium time deviation from the average value = (historical cumulative equilibrium time - average historical cumulative equilibrium time of all monomers) / average historical cumulative equilibrium time of all monomers

[0139] Determine the average capacity of all cells to be balanced by the basic capacity of each cell to be balanced; determine the average deviation ratio of the current capacity of each cell to be balanced by the basic capacity of each cell to be balanced and the average capacity of all cells to be balanced;

[0140] The current average deviation ratio of the capacity to be balanced = (the basic capacity to be balanced of each monomer to be balanced - the average capacity to be balanced of all monomers to be balanced) / the average capacity to be balanced of all monomers to be balanced

[0141] Finally, the historical cumulative balancing time coefficient of each to-be-balanced cell is determined by the ratio of the cumulative balancing time of each to-be-balanced cell to deviate from the average value and the ratio of the current to-be-balanced capacity to deviate from the average value.

[0142] For the monomers not to be balanced identified in S201, the monomer historical cumulative balancing time coefficient K1 is set to 0; and in order to control the excessive correction of the historical cumulative balancing time to the capacity to be balanced, the upper and lower limits of the historical cumulative balancing time coefficient K1 of each monomer to be balanced need to be set.

[0143] The following is an example based on the method described above:

[0144] Assuming that there are 96 cells in the battery pack, the BMS reads the historical cumulative balancing time of each cell stored in the EEPROM after power-on. The historical cumulative balancing time of the first cell is 100 hours, the historical cumulative balancing time of the second cell is 800 hours, and the cumulative balancing time of the remaining cells is 200 hours. If only the second cell is balanced in this driving cycle and 5 hours of balancing are performed, the cumulative balancing time of the second cell stored in the EEPROM is updated to 805 hours, and the historical cumulative balancing time of the remaining cells remains unchanged.

[0145] Assume that there are 96 cells in the battery pack, the historical cumulative balancing time of the first cell is 100 hours, the historical cumulative balancing time of the second cell is 800 hours, and the cumulative balancing time of the remaining cells is 200 hours. The average historical cumulative balancing time of all cells is 205.2 hours. The deviation ratio of the cumulative balancing time of the first cell from the average value is: (100-205.2) / 205.2=-0.51267; the deviation ratio of the cumulative balancing time of the second cell from the average value is: (800-205.2) / 205.2=2.89864; the deviation ratio of the cumulative balancing time of the remaining cells from the average value is: (200-205.2) / 205.2=-0.02534.

[0146] Assume that the basic capacity of the monomer to be balanced in the first section is Q demand 0AH, which is a non-balanced monomer. The basic balance capacity of the second section monomer to be balanced is Q demand The basic capacity of the remaining monomers to be balanced is Q demand is 0.35AH, then the average basic capacity to be balanced of all monomers is Q demand It is 0.359AH. The average value of the current monomer capacity to be balanced in the first section is (0-0.359) / 0.359=-1; the average value of the current monomer capacity to be balanced in the second section is (1.6-0.359) / 0.359=3.45682; the average value of the current monomer capacity to be balanced in the remaining sections is (0.35-0.359) / 0.359=-0.02507.

[0147] The historical cumulative balancing time coefficient K1 of the first section's monomer to be balanced is -0.51267 / -1=0.51267; the historical cumulative balancing time coefficient K1 of the second section's monomer to be balanced is 2.89864 / 3.457=0.83853, and the historical cumulative balancing time coefficient K1 of the remaining monomers to be balanced is -0.02534 / -0.02507=1.01077.

[0148] Finally, assume that the upper and lower limits of the historical cumulative balancing time coefficient K1 of each monomer to be balanced are [0.8, 1.1]. Therefore, the K1 of the first section monomer is 0.8, the K1 of the second section monomer is 0.83853, and the remaining monomers are 1.01077.

[0149] Step 204, respectively obtain the depolarization speed of each to-be-balanced monomer and the depolarization speed of the comparison monomer in the database, and respectively determine the depolarization coefficient of each to-be-balanced monomer by the depolarization speed of each to-be-balanced monomer and the depolarization speed of the comparison monomer in the database. The specific contents are as follows:

[0150] Test cells at different temperatures and aging states, collect depolarization data (changes in cell voltage over time after full charge) from different starting SOCs through fast charging, and then create a basic database. (2) When the vehicle is fast-charging, the BMS records the starting SOC of charging, cell temperature and other data, and evaluates whether the fast-charging condition matches the data in the database when the vehicle is fully charged. If so, store the voltage of each cell in the EEPROM; (3) If the vehicle is in sleep mode, the BMS wakes itself up at a certain time interval (depolarization is fast in the early stage of sleep mode, and the wake-up time interval is short; depolarization is slow in the later stage, and the wake-up time interval is long. When the temperature is high, the depolarization is fast and the wake-up time interval is short; when the temperature is low, the depolarization is slow and the wake-up time interval is long), records the changes in battery voltage, and evaluates the depolarization of the cell.

[0151] If the depolarization of the monomer is consistent with the data in the database, the capacity to be balanced does not need to be corrected; if the depolarization of the monomer is inconsistent with the data in the database, the capacity to be balanced of the monomer needs to be corrected. The monomer depolarization rate is proportional to the monomer capacity to be balanced. The faster the monomer depolarization, the larger the capacity to be balanced; the slower the monomer depolarization, the smaller the capacity to be balanced.

[0152] Define K2 as the depolarization coefficient of each monomer to be balanced, and its calculation formula is:

[0153] K2 = depolarization speed of each monomer to be balanced / depolarization speed of the comparison monomer in the database

[0154] In addition, if the depolarization coefficient judgment condition is not met, the depolarization coefficient K2 of each to-be-balanced cell is set to 1. In order to control the excessive correction of the to-be-balanced capacity by the cell depolarization, the upper and lower limits of K2 need to be set.

[0155] The following is an example based on the method described above:

[0156] Assuming that the vehicle goes into sleep mode after being fully charged, and the fast charging process matches the fast charging process in the database, the BMS will record the current charging status in the EEPROM. At normal temperature, the BMS needs to wake up every two minutes for the first half hour after sleep, every five minutes for the second half hour, and every 10 minutes thereafter, until the voltage change amplitude of the cell does not exceed 2mV after three wake-ups. If the cell temperature is 35 degrees Celsius, the wake-up interval is reduced by 1 / 2 based on the normal temperature; if the cell temperature is 5 degrees Celsius, the wake-up interval is increased by 1 / 3 based on the normal temperature.

[0157] Assume that there are 96 cells in the battery pack, the vehicle goes into sleep mode after being fully charged with fast charging, and the fast charging process matches the fast charging process in the database. After the BMS wakes up, it identifies that the depolarization of the cells is inconsistent with the data in the database. The depolarization speed V1 of the first cell is 1.25mV / S, the depolarization speed V2 of the second cell is 1.5mV / S, the depolarization speed V2 of the third cell is 1mV / S, the depolarization speed V2 of the fourth cell is 1.15mV / S, and the depolarization speeds of the remaining cells are The speed is 1.21mV / S, and the comparison monomer depolarization speed in the database is 1.20mV / S. Then the depolarization coefficient of the first monomer is K2=1.25 / 1.2=1.04, the depolarization coefficient of the second monomer is K2=1.5 / 1.2=1.25, the depolarization coefficient of the third monomer is K2=1 / 1.2=0.83, the depolarization coefficient of the fourth monomer is K2=1.15 / 1.2=0.96, and the depolarization coefficients of the remaining monomers are K2=1.21 / 1.2=1.01.

[0158] Assuming that the upper and lower limits of the monomer depolarization coefficient K2 are [0.9, 1.1], the depolarization coefficient K2 of the first section monomer is 1.04, the depolarization coefficient K2 of the second section is 1.1, the depolarization coefficient K2 of the third section is 0.9, the depolarization coefficient K2 of the fourth section is 0.96, and the depolarization coefficient K2 of the remaining monomers is 1.01.

[0159] Step 205, determine the capacity to be balanced of each monomer to be balanced according to the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient, and select a passive balancing method to perform balanced discharge on each monomer to be balanced according to the capacity to be balanced of each monomer to be balanced.

[0160] The capacity to be balanced of each monomer to be balanced is determined by formula 2 through the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient:

[0161] Q=Q selfdis +Q demand ×K1×K2 (1)

[0162] Where: Q is the capacity of each unit to be balanced, Q selfdis is the basic capacity of each unit to be balanced, Q demand is the capacity to be balanced caused by the difference in self-discharge rates of each to-be-balanced monomer, K1 is the historical cumulative balancing time coefficient of each to-be-balanced monomer, and K2 is the depolarization coefficient of each to-be-balanced monomer.

[0163] Passive balancing is adopted to discharge each monomer to be balanced by using the capacity to be balanced of each monomer to be balanced.

[0164] This patent comprehensively considers the consistency differences of the monomers in the future through the following dimensions, and then accurately estimates the monomer capacity to be balanced: (1) Identify the current capacity of different monomers in the battery pack through the current open circuit voltage, temperature, battery health status, etc.; (2) Determine the capacity change of the monomer in the future by identifying the self-discharge rate of the monomer, which is used to calculate the capacity to be balanced caused by the self-discharge rate difference; (3) Determine the capacity difference between each monomer through the historical cumulative balancing time of the monomer, which is used to correct the monomer capacity to be balanced; (4) Identify the electrochemical characteristics of the monomer through the depolarization of the battery after fast charging, especially the concentration polarization recovery state, and correct the monomer capacity to be balanced.

[0165] Embodiment 3

[0166] In an exemplary embodiment, Figure 6 is a block diagram of a monomer consistency difference estimation system according to an exemplary embodiment, the system comprising:

[0167] The preliminary estimation module 310 is used to obtain the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, and the open circuit voltage, battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell, and respectively determine the basic capacity to be balanced and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced;

[0168] The coefficient estimation module 320 is used to respectively obtain the historical cumulative balancing time, depolarization speed and the comparative monomer depolarization speed in the database of each monomer to be balanced, and determine the historical cumulative balancing time coefficient and depolarization coefficient of each monomer to be balanced according to the basic capacity to be balanced, the historical cumulative balancing time, the depolarization speed and the comparative monomer depolarization speed in the database of each monomer to be balanced;

[0169] The final estimation module 330 is used to determine the capacity to be balanced of each monomer to be balanced through the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient, and select the passive balancing method to perform balanced discharge on each monomer to be balanced through the capacity to be balanced of each monomer to be balanced.

[0170] Preferably, the final estimation module 330 is used to:

[0171] The capacity to be balanced of each monomer to be balanced is determined by formula 1 through the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient:

[0172] Q=Q selfdis +Q demand ×K1×K2 (1)

[0173] Wherein: Q is the capacity to be balanced of each monomer to be balanced, Q selfdis is the basic capacity to be balanced of each monomer to be balanced, Q demand is the capacity to be balanced caused by the self-discharge rate difference of each monomer to be balanced, K1 is the historical cumulative balancing time coefficient of each monomer to be balanced, and K2 is the depolarization coefficient of each monomer to be balanced.

[0174] The present invention can predict the sound pressure level and spectrum changes of the low-speed pedestrian warning sound in advance by measuring the frequency response characteristics of the low-speed pedestrian warning sound system of the electric vehicle and the transfer function on its transmission path. Therefore, by designing the sound source, the sound pressure level and spectrum changes can be compensated in advance, thereby solving the problem of distortion of the warning sound heard by pedestrians.

[0175] Embodiment 4

[0176] Figure 7 400 is a block diagram of a terminal provided in an embodiment of the present application, and the terminal may be a terminal in the above embodiment. The terminal 400 may be a portable mobile terminal, such as a smart phone or a tablet computer. The terminal 400 may also be referred to as a user equipment, a portable terminal, or other names.

[0177] Typically, the terminal 400 includes a processor 401 and a memory 402 .

[0178] The processor 401 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 401 may be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). The processor 401 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 401 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 401 may also include an AI (Artificial Intelligence) processor, which is used to process computing operations related to machine learning.

[0179] The memory 402 may include one or more computer-readable storage media, which may be tangible and non-transitory. The memory 402 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In some embodiments, the non-transitory computer-readable storage medium in the memory 402 is used to store at least one instruction, which is used to be executed by the processor 401 to implement a cell consistency difference estimation method provided in the present application.

[0180] In some embodiments, the terminal 400 may further include: a peripheral device interface 403 and at least one peripheral device. Specifically, the peripheral device includes: at least one of a radio frequency circuit 404 , a touch screen 405 , a camera 406 , an audio circuit 407 , a positioning component 408 and a power supply 409 .

[0181] The peripheral device interface 403 may be used to connect at least one peripheral device related to I / O (Input / Output) to the processor 401 and the memory 402. In some embodiments, the processor 401, the memory 402, and the peripheral device interface 403 are integrated on the same chip or circuit board; in some other embodiments, any one or two of the processor 401, the memory 402, and the peripheral device interface 403 may be implemented on a separate chip or circuit board, which is not limited in this embodiment.

[0182] The radio frequency circuit 404 is used to receive and transmit RF (Radio Frequency) signals, also known as electromagnetic signals. The radio frequency circuit 404 communicates with the communication network and other communication devices through electromagnetic signals. The radio frequency circuit 404 converts the electrical signal into an electromagnetic signal for transmission, or converts the received electromagnetic signal into an electrical signal. Optionally, the radio frequency circuit 404 includes: an antenna system, an RF transceiver, one or more amplifiers, a tuner, an oscillator, a digital signal processor, a codec chipset, a user identity module card, etc. The radio frequency circuit 404 can communicate with other terminals through at least one wireless communication protocol. The wireless communication protocol includes but is not limited to: the World Wide Web, a metropolitan area network, an intranet, various generations of mobile communication networks (2G, 3G, 4G and 5G), a wireless local area network and / or a WiFi (Wireless Fidelity) network. In some embodiments, the radio frequency circuit 404 may also include circuits related to NFC (Near Field Communication), which is not limited in this application.

[0183] The touch display screen 405 is used to display the UI (User Interface). The UI may include graphics, text, icons, videos and any combination thereof. The touch display screen 405 also has the ability to collect touch signals on the surface or above the surface of the touch display screen 405. The touch signal can be input to the processor 401 as a control signal for processing. The touch display screen 405 is used to provide virtual buttons and / or virtual keyboards, also known as soft buttons and / or soft keyboards. In some embodiments, the touch display screen 405 can be one, and the front panel of the terminal 400 is set; in other embodiments, the touch display screen 405 can be at least two, which are respectively set on different surfaces of the terminal 400 or are folded; in some other embodiments, the touch display screen 405 can be a flexible display screen, which is set on the curved surface or folded surface of the terminal 400. Even, the touch display screen 405 can also be set to a non-rectangular irregular shape, that is, a special-shaped screen. The touch display screen 405 can be made of materials such as LCD (Liquid Crystal Display), OLED (Organic Light-Emitting Diode, organic light-emitting diode).

[0184] The camera assembly 406 is used to capture images or videos. Optionally, the camera assembly 406 includes a front camera and a rear camera. Typically, the front camera is used to realize video calls or selfies, and the rear camera is used to realize the shooting of photos or videos. In some embodiments, there are at least two rear cameras, which are any one of a main camera, a depth of field camera, and a wide-angle camera, so as to realize the fusion of the main camera and the depth of field camera to realize the background blur function, and the fusion of the main camera and the wide-angle camera to realize panoramic shooting and VR (Virtual Reality) shooting functions. In some embodiments, the camera assembly 406 may also include a flash. The flash can be a monochrome temperature flash or a dual-color temperature flash. A dual-color temperature flash refers to a combination of a warm light flash and a cold light flash, which can be used for light compensation at different color temperatures.

[0185] The audio circuit 407 is used to provide an audio interface between the user and the terminal 400. The audio circuit 407 may include a microphone and a speaker. The microphone is used to collect sound waves from the user and the environment, and convert the sound waves into electrical signals and input them into the processor 401 for processing, or input them into the radio frequency circuit 404 to achieve voice communication. For the purpose of stereo acquisition or noise reduction, there may be multiple microphones, which are respectively arranged at different parts of the terminal 400. The microphone may also be an array microphone or an omnidirectional acquisition microphone. The speaker is used to convert the electrical signal from the processor 401 or the radio frequency circuit 404 into sound waves. The speaker may be a traditional film speaker or a piezoelectric ceramic speaker. When the speaker is a piezoelectric ceramic speaker, it can not only convert the electrical signal into sound waves audible to humans, but also convert the electrical signal into sound waves inaudible to humans for purposes such as ranging. In some embodiments, the audio circuit 407 may also include a headphone jack.

[0186] Positioning component 408 is used to locate the current geographical location of terminal 400 to implement navigation or LBS (Location Based Service). Positioning component 408 can be a positioning component based on the US GPS (Global Positioning System), China's Beidou system or Russia's Galileo system.

[0187] The power supply 409 is used to power various components in the terminal 400. The power supply 409 can be an alternating current, a direct current, a disposable battery, or a rechargeable battery. When the power supply 409 includes a rechargeable battery, the rechargeable battery can be a wired rechargeable battery or a wireless rechargeable battery. A wired rechargeable battery is a battery charged through a wired line, and a wireless rechargeable battery is a battery charged through a wireless coil. The rechargeable battery can also be used to support fast charging technology.

[0188] In some embodiments, the terminal 400 further includes one or more sensors 410 , including but not limited to: an acceleration sensor 411 , a gyroscope sensor 412 , a pressure sensor 413 , a fingerprint sensor 414 , an optical sensor 415 , and a proximity sensor 416 .

[0189] The acceleration sensor 411 can detect the magnitude of acceleration on the three coordinate axes of the coordinate system established by the terminal 400. For example, the acceleration sensor 411 can be used to detect the components of gravity acceleration on the three coordinate axes. The processor 401 can control the touch display screen 405 to display the user interface in a horizontal view or a vertical view according to the gravity acceleration signal collected by the acceleration sensor 411. The acceleration sensor 411 can also be used for collecting game or user motion data.

[0190] The gyroscope sensor 412 can detect the body direction and rotation angle of the terminal 400. The gyroscope sensor 412 can cooperate with the acceleration sensor 411 to collect the user's 3D (3 Dimensions) action on the terminal 400. The processor 401 can implement the following functions based on the data collected by the gyroscope sensor 412: motion sensing (such as changing the UI according to the user's tilt operation), image stabilization during shooting, game control, and inertial navigation.

[0191] The pressure sensor 413 can be set in the side frame of the terminal 400 and / or the lower layer of the touch display screen 405. When the pressure sensor 413 is set in the side frame of the terminal 400, it can detect the user's holding signal of the terminal 400, and perform left and right hand recognition or shortcut operation according to the holding signal. When the pressure sensor 413 is set in the lower layer of the touch display screen 405, it can control the operability control on the UI interface according to the user's pressure operation on the touch display screen 405. The operability control includes at least one of a button control, a scroll bar control, an icon control, and a menu control.

[0192] The fingerprint sensor 414 is used to collect the user's fingerprint to identify the user's identity based on the collected fingerprint. When the user's identity is identified as a trusted identity, the processor 401 authorizes the user to perform relevant sensitive operations, including unlocking the screen, viewing encrypted information, downloading software, paying, and changing settings. The fingerprint sensor 414 can be set on the front, back, or side of the terminal 400. When a physical button or a manufacturer logo is set on the terminal 400, the fingerprint sensor 414 can be integrated with the physical button or the manufacturer logo.

[0193] The optical sensor 415 is used to collect the ambient light intensity. In one embodiment, the processor 401 can control the display brightness of the touch display screen 405 according to the ambient light intensity collected by the optical sensor 415. Specifically, when the ambient light intensity is high, the display brightness of the touch display screen 405 is increased; when the ambient light intensity is low, the display brightness of the touch display screen 405 is reduced. In another embodiment, the processor 401 can also dynamically adjust the shooting parameters of the camera assembly 406 according to the ambient light intensity collected by the optical sensor 415.

[0194] The proximity sensor 416, also called a distance sensor, is usually arranged on the front of the terminal 400. The proximity sensor 416 is used to collect the distance between the user and the front of the terminal 400. In one embodiment, when the proximity sensor 416 detects that the distance between the user and the front of the terminal 400 is gradually decreasing, the processor 401 controls the touch display screen 405 to switch from the screen-on state to the screen-off state; when the proximity sensor 416 detects that the distance between the user and the front of the terminal 400 is gradually increasing, the processor 401 controls the touch display screen 405 to switch from the screen-off state to the screen-on state.

[0195] Those skilled in the art will understand that Figure 7 The structure shown in the figure does not constitute a limitation on the terminal 400, and the terminal 400 may include more or less components than those shown in the figure, or combine some components, or adopt a different component arrangement.

[0196] Embodiment 5

[0197] In an exemplary embodiment, a computer-readable storage medium is also provided, on which a computer program is stored. When the program is executed by a processor, a method for estimating battery cell consistency differences as provided in all the inventive embodiments of the present application is implemented.

[0198] Any combination of one or more computer-readable media may be used. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, device, or device.

[0199] Computer-readable signal media may include a data signal propagated in baseband or as part of a carrier wave, which carries a computer-readable program code. Such propagated data signals may take a variety of forms, including, but not limited to, electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0200] Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0201] Computer program code for performing the operations of the present invention may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0202] Embodiment 6

[0203] In an exemplary embodiment, an application product is also provided, including one or more instructions, which can be executed by the processor 401 of the above-mentioned device to complete the above-mentioned method for estimating the consistency difference of battery cells.

[0204] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and the embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily realized. Therefore, without departing from the general concept defined by the claims and equivalent scope, the present invention is not limited to the specific details and the illustrations shown and described here.

Claims

1. A method for estimating cell consistency difference, characterized in that: include: The average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, as well as the open circuit voltage, battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell are obtained respectively, and the basic capacity to be balanced and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced are determined respectively; The historical cumulative balancing time, depolarization speed and the depolarization speed of the comparison monomer in the database of each monomer to be balanced are obtained respectively, and the historical cumulative balancing time coefficient and depolarization coefficient of each monomer to be balanced are determined respectively according to the basic capacity to be balanced, the historical cumulative balancing time, the depolarization speed and the depolarization speed of the comparison monomer in the database of each monomer to be balanced; The capacity to be balanced of each monomer to be balanced is determined by the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient, and the passive balancing method is selected to perform balanced discharge on each monomer to be balanced according to the capacity to be balanced of each monomer to be balanced; The average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, the open circuit voltage of each cell, the battery health status, the battery rated capacity, and the capacity error caused by the voltage sampling error are obtained respectively, and the basic capacity to be balanced and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced are determined respectively, including: The open circuit voltage, battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell are obtained respectively, and the basic capacity to be balanced of each cell to be balanced is determined; The average daily wake-up time of the vehicle, the average balancing current, and the self-discharge rate difference between the lowest voltage cell and the cell to be balanced are obtained respectively, and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced is determined by the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, and the battery health status, battery rated capacity, and basic capacity to be balanced of each cell to be balanced; Obtain the open circuit voltage, battery health status and battery rated capacity of each cell respectively, and determine the basic capacity to be balanced of each cell to be balanced, including: Obtain the open circuit voltage of each cell respectively, and determine the charge data of each cell through the open circuit voltage and OCV-SOC table; Get the battery rest time and determine whether it is greater than the preset rest time: Yes, proceed to the next step; No, the electrolyte distribution of each monomer is uneven, and the execution ends; Determine the lowest voltage monomer charging data through each monomer charging data and open circuit voltage; The difference between each monomer charge data and the lowest voltage monomer charge data is used to determine whether it is greater than the preset threshold: Yes, the corresponding monomers are monomers to be balanced; If not, the corresponding capacity to be balanced of each monomer is 0; Obtain the battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell to be balanced and the cell with the lowest voltage respectively; Determine the basic capacity of each cell to be balanced by the battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell to be balanced and the cell with the lowest voltage; The capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced is determined by the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, the battery health status of each cell to be balanced, the battery rated capacity of each cell and the basic capacity to be balanced, including: Determine the self-discharge capacity difference of each to-be-balanced cell by the battery health status, the battery rated capacity and the self-discharge rate difference between the lowest voltage cell and the to-be-balanced cell; The capacity to be balanced caused by the self-discharge rate difference of each to-be-balanced cell is determined by the average daily wake-up time of the vehicle, the average balancing current, the basic to-be-balanced capacity of each to-be-balanced cell, and the monthly self-discharge rate difference.

2. A method for estimating cell consistency differences according to claim 1, characterized in that: The historical cumulative balancing time coefficient and depolarization coefficient of each to-be-balanced monomer are determined respectively by the basic to-be-balanced capacity, historical cumulative balancing time, depolarization speed and depolarization speed of the comparison monomer in the database, including: Determine the average historical cumulative balancing time of all monomers to be balanced through the historical cumulative balancing time of each monomer to be balanced; Determine the deviation ratio of the cumulative balancing time of each monomer to be balanced from the average value through the historical cumulative balancing time of each monomer to be balanced and the average historical cumulative balancing time of all monomers; Determine the average capacity of all cells to be balanced by using the basic capacity of each cell to be balanced. Determine the average deviation ratio of the current capacity to be balanced of each to-be-balanced cell through the basic capacity to be balanced of each to-be-balanced cell and the average capacity to be balanced of all to-be-balanced cells; The historical cumulative balancing time coefficient of each to-be-balanced cell is determined by the ratio of the cumulative balancing time of each to-be-balanced cell to deviate from the average value and the ratio of the current to-be-balanced capacity to deviate from the average value; The depolarization coefficient of each monomer to be balanced is determined by the depolarization speed of each monomer to be balanced and the depolarization speed of the comparison monomer in the database.

3. A method for estimating cell consistency differences according to claim 1, characterized in that: The capacity to be balanced of each monomer to be balanced is determined by formula 1 through the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient: Q=Q selfdis +Q demand ×K1×K2 (1) Where: Q is the capacity of each unit to be balanced, Q selfdis is the basic capacity of each unit to be balanced, Q demand is the capacity to be balanced caused by the difference in self-discharge rates of each to-be-balanced monomer, K1 is the historical cumulative balancing time coefficient of each to-be-balanced monomer, and K2 is the depolarization coefficient of each to-be-balanced monomer.

4. A battery cell consistency difference estimation system, characterized in that: include: The preliminary estimation module is used to obtain the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, as well as the open circuit voltage of each cell, the battery health status, the battery rated capacity and the capacity error caused by the voltage sampling error, and respectively determine the basic capacity to be balanced and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced; The coefficient estimation module is used to obtain the historical cumulative balancing time, depolarization speed and depolarization speed of the comparison monomer in the database of each monomer to be balanced, and determine the historical cumulative balancing time coefficient and depolarization coefficient of each monomer to be balanced according to the basic capacity to be balanced, the historical cumulative balancing time, the depolarization speed and the depolarization speed of the comparison monomer in the database of each monomer to be balanced; The final estimation module is used to determine the capacity to be balanced of each monomer to be balanced through the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient, and select the passive balancing method to balance the discharge of each monomer to be balanced according to the capacity to be balanced of each monomer to be balanced; The average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, the open circuit voltage of each cell, the battery health status, the battery rated capacity, and the capacity error caused by the voltage sampling error are obtained respectively, and the basic capacity to be balanced and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced are determined respectively, including: The open circuit voltage, battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell are obtained respectively, and the basic capacity to be balanced of each cell to be balanced is determined; The average daily wake-up time of the vehicle, the average balancing current, and the self-discharge rate difference between the lowest voltage cell and the cell to be balanced are obtained respectively, and the capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced is determined by the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, and the battery health status, battery rated capacity, and basic capacity to be balanced of each cell to be balanced; Obtain the open circuit voltage, battery health status and battery rated capacity of each cell respectively, and determine the basic capacity to be balanced of each cell to be balanced, including: Obtain the open circuit voltage of each cell respectively, and determine the charge data of each cell through the open circuit voltage and OCV-SOC table; Get the battery rest time and determine whether it is greater than the preset rest time: Yes, proceed to the next step; No, the electrolyte distribution of each monomer is uneven, and the execution ends; Determine the lowest voltage monomer charging data through each monomer charging data and open circuit voltage; The difference between each monomer charge data and the lowest voltage monomer charge data is used to determine whether it is greater than the preset threshold: Yes, the corresponding monomers are monomers to be balanced; If not, the corresponding capacity to be balanced of each monomer is 0; Obtain the battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell to be balanced and the cell with the lowest voltage respectively; Determine the basic capacity of each cell to be balanced by the battery health status, battery rated capacity and capacity error caused by voltage sampling error of each cell to be balanced and the cell with the lowest voltage; The capacity to be balanced caused by the self-discharge rate difference of each cell to be balanced is determined by the average daily wake-up time of the vehicle, the average balancing current, the self-discharge rate difference between the lowest voltage cell and the cell to be balanced, the battery health status of each cell to be balanced, the battery rated capacity of each cell and the basic capacity to be balanced, including: Determine the self-discharge capacity difference of each to-be-balanced cell by the battery health status, the battery rated capacity and the self-discharge rate difference between the lowest voltage cell and the to-be-balanced cell; The capacity to be balanced caused by the self-discharge rate difference of each to-be-balanced cell is determined by the average daily wake-up time of the vehicle, the average balancing current, the basic to-be-balanced capacity of each to-be-balanced cell, and the monthly self-discharge rate difference.

5. A battery cell consistency difference estimation system according to claim 4, characterized in that: The final estimation module is used to: The capacity to be balanced of each monomer to be balanced is determined by formula 1 through the basic capacity to be balanced of each monomer to be balanced, the capacity to be balanced caused by the self-discharge rate difference, the historical cumulative balancing time coefficient and the depolarization coefficient: Q=Q selfdis +Q demand ×K1×K2 (1) Where: Q is the capacity of each unit to be balanced, Q selfdis is the basic capacity of each unit to be balanced, Q demand is the capacity to be balanced caused by the difference in self-discharge rates of each to-be-balanced monomer, K1 is the historical cumulative balancing time coefficient of each to-be-balanced monomer, and K2 is the depolarization coefficient of each to-be-balanced monomer.

6. A terminal, characterized in that: include: one or more processors; a memory for storing the one or more processor-executable instructions; Wherein, the one or more processors are configured to: Execute a method for estimating battery cell consistency differences as described in any one of claims 1 to 3.

7. A non-transitory computer-readable storage medium, characterized in that: When the instructions in the storage medium are executed by the processor of the terminal, the terminal is enabled to execute a method for estimating battery cell consistency differences as described in any one of claims 1 to 3.

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