CN112541260B - Battery balancing control method, system, storage medium and electronic device - Google Patents

Abstract

The present invention discloses a battery balancing control method, system, storage medium and electronic device, and relates to the technical field of battery management systems. The method comprises: obtaining the average capacity and target capacity of a battery pack according to the capacity of each battery cell; determining the target battery cell that meets the preset conditions as the battery cell to be balanced, wherein the preset conditions include that the first parameter of the target battery cell is within the preset balancing mark threshold range, and the capacity of the target battery cell is greater than the average capacity and the target capacity; then obtaining the balancing time of the battery cell to be balanced according to the capacity of the battery cell to be balanced and the preset balancing current; finally, balancing the battery cell to be balanced within the balancing time. The present invention solves the problem that the existing battery passive balancing scheme is prone to over-balancing or mis-balancing, and achieves the technical effect of improving the energy utilization rate of the battery and extending the battery life.

Description

Battery balancing control method, system, storage medium and electronic device

Technical Field

The present invention relates to the technical field of battery management systems, and in particular to a battery balancing control method, system, storage medium and electronic equipment.

Background technique

When the battery pack leaves the factory, there are differences in the consistency of the manufacturing process. During use, due to the influence of running time and self-discharge, there are also differences in the consistency of its capacity. Therefore, the battery pack needs to be balanced to ensure the consistency of the battery throughout its life cycle. The current mainstream battery balancing methods are active balancing and passive balancing. Among them, the passive balancing solution includes voltage balancing and capacity balancing. The voltage balancing is started and turned on and off in real time through the voltage difference; the capacity balancing is controlled by the SOC difference.

At present, the passive balancing control in the power battery system calculates the average remaining capacity of each battery cell in the power battery system by differentiating the remaining charging capacity and voltage of the battery at the end of charging, and controls the battery cells in the power battery system with a remaining capacity higher than the average, so as to dissipate the discharge of the battery cells with high remaining capacity during the next charge and discharge cycle. This scheme increases the daily balancing time from a few minutes to 8 to 10 hours, thereby improving the efficiency of passive balancing. However, this scheme is prone to the risk of over-balancing and mis-balancing, which is not conducive to the stability of the battery, thereby reducing the energy utilization of the battery.

Therefore, the existing passive battery balancing solutions have technical problems of over-balancing or mis-balancing.

The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art.

Summary of the invention

The main purpose of the present invention is to provide a battery balancing control method, system, storage medium and electronic device, aiming to solve the technical problem that the battery passive balancing solution in the prior art easily leads to over-balancing or mis-balancing.

The technical solution adopted by the present invention is as follows:

To achieve the above objectives, in a first aspect, the present invention provides a battery balancing control method, comprising the following steps:

Obtaining the first parameter and capacity of each battery cell in the battery pack;

According to the capacity of each battery cell, obtaining the minimum capacity and average capacity of the battery pack;

Obtaining a target capacity of the battery pack according to the minimum capacity;

Determine a target cell that meets a preset condition as a cell to be balanced, wherein the preset condition includes: a first parameter of the target cell is within a preset balancing mark threshold range, and a capacity of the target cell is greater than the average capacity and the target capacity;

Obtaining a balancing time of the battery cell to be balanced according to the capacity of the battery cell to be balanced and a preset balancing current;

The battery cells to be balanced are balanced within the balancing time of the battery cells to be balanced.

Optionally, in the above battery balancing control method, the first parameter includes real-time voltage, real-time temperature, real-time current and static time;

The step of determining the target battery cells that meet the preset conditions as the battery cells to be balanced specifically includes:

Determine whether the real-time voltage, real-time temperature, real-time current and static time of the target battery cell are all within the corresponding preset balancing mark threshold range;

When the real-time voltage, real-time temperature, real-time current and standing time of the target battery cell are all within the preset marking threshold range, further determining whether the capacity of the target battery cell is greater than the average capacity and the target capacity;

If the capacity of the target cell is greater than the average capacity and greater than the target capacity, the target cell is determined to be a cell to be balanced.

Optionally, in the above battery balancing control method, after the step of obtaining the balancing time of the battery cell to be balanced according to the capacity of the battery cell to be balanced and the preset balancing current, the method further includes:

The serial numbers corresponding to the cells to be balanced and their balancing durations are stored.

Optionally, in the above battery balancing control method, the step of balancing the battery cells to be balanced within the balancing time of the battery cells to be balanced specifically includes:

During the balanced discharge of the battery cells to be balanced, if the battery pack is powered off, the current balancing is interrupted, and the serial numbers and remaining balancing time corresponding to the battery cells to be balanced are stored.

Optionally, in the above battery balancing control method, the step of balancing the battery cells to be balanced within the balancing time of the battery cells to be balanced specifically includes:

According to the stored serial number corresponding to the battery cell to be balanced, determining whether the second parameter of the battery cell to be balanced is within a preset balancing execution threshold range;

If the stored second parameter of the battery cell to be balanced is within a preset balancing execution threshold range, the battery cell to be balanced is balanced according to the stored remaining balancing time of the battery cell to be balanced.

Optionally, in the above battery balancing control method, the second parameter includes real-time voltage and real-time temperature;

The step of judging whether the second parameter of the battery cell to be balanced is within a preset balancing execution threshold range according to the stored serial number corresponding to the battery cell to be balanced specifically includes:

According to the stored serial numbers of the cells to be balanced, the real-time voltage and the real-time temperature of the cells to be balanced are obtained;

Determine whether the real-time voltage and the real-time temperature of the battery cell to be balanced are both within the corresponding preset balancing execution threshold range;

If the stored second parameter of the battery cell to be balanced is within a preset balancing execution threshold range, the step of balancing the battery cell to be balanced according to the stored remaining balancing time of the battery cell to be balanced specifically includes:

When the stored real-time voltage and real-time temperature of the battery cell to be balanced are both within the corresponding preset balancing execution threshold range, the battery cell to be balanced is balanced according to the stored remaining balancing time of the battery cell to be balanced.

Optionally, in the above battery balancing control method, after the step of balancing the battery cells to be balanced within the balancing time of the battery cells to be balanced, the method further includes:

When the balancing time ends, the stored serial numbers corresponding to the cells to be balanced are cleared, and the current balancing is terminated.

In a second aspect, the present invention provides a battery balancing control system, the system comprising:

A parameter acquisition module, used for acquiring a first parameter of each battery cell in the battery pack;

A capacity module, connected to the parameter acquisition module, for obtaining the capacity of each battery cell according to the first parameter of each battery cell, and obtaining the minimum capacity and average capacity of the battery pack according to the capacity of each battery cell;

a target capacity module, connected to the capacity module, and configured to obtain a target capacity of the battery pack according to the minimum capacity;

a balancing marking module, connected to the parameter acquisition module and the target capacity module, and configured to determine a target cell that meets a preset condition as a cell to be balanced, wherein the preset condition includes: a first parameter of the target cell is within a preset balancing marking threshold range, and a capacity of the target cell is greater than the average capacity and the target capacity;

A balancing time module, connected to the balancing mark module, for obtaining the balancing time of the battery cell to be balanced according to the capacity of the battery cell to be balanced and a preset balancing current;

The balancing execution module is connected to the balancing duration module and is used to balance the battery cells to be balanced within the balancing duration of the battery cells to be balanced.

In a third aspect, the present invention provides a storage medium having a computer program stored thereon, wherein the computer program can be executed by one or more processors to implement the battery balancing control method as described above.

In a fourth aspect, the present invention provides an electronic device, comprising a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the battery balancing control method as described above is executed.

One or more technical solutions provided by the present invention have at least the following advantages or technical effects:

The present invention proposes a battery balancing control method, system, storage medium and electronic device. By setting a target capacity according to the minimum capacity of a battery pack, a target cell that satisfies a first parameter within a preset balancing mark threshold range and whose capacity is greater than the average capacity and the target capacity is determined as a cell to be balanced, thereby ensuring the consistency of battery balancing and preventing over-balancing and mis-balancing. After obtaining the balancing time of the cell to be balanced according to the capacity of the cell to be balanced and a preset balancing current, the cell to be balanced is discharged within the balancing time of the cell to be balanced, thereby ensuring sufficient balancing power while reducing the consistency difference caused by different factory specifications of the battery and different battery life, thereby achieving the technical effect of improving the energy utilization rate of the battery and extending the battery life.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

FIG1 is a schematic flow chart of a battery balancing control method provided in Embodiment 1 of the present invention;

FIG2 is another schematic flow chart of a battery balancing control method provided by Embodiment 2 of the present invention;

FIG. 3 is a schematic diagram of functional modules of a battery balancing control system provided in Embodiment 3 of the present invention.

The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings.

Detailed ways

In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all 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.

It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" 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 an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and/or" appearing in the full text includes three parallel schemes. Taking "A and/or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Analysis of the prior art shows that, at present, there are some problems with the passive balancing control scheme designed to ensure the life of the battery and to ensure the balance between battery inconsistency and balancing amount. For example, the voltage difference balancing scheme used in the battery charging process cannot ensure the consistency of the battery pack when the battery capacity difference and internal resistance difference are large due to the limitation of balancing conditions and the insufficient balancing time and balancing current, especially at the end of the battery life. For another example, the capacity balancing control in the power battery system calculates the average remaining capacity of each battery cell in the power battery system by the battery remaining charging capacity and voltage differentiation at the end of charging, and controls the battery cells with higher than the average remaining capacity in the power battery system to dissipate the discharge of the battery cells with high remaining capacity during the next charge and discharge cycle; the scheme does not limit the balancing capacity for the balancing current and balancing time, and is prone to the risk of over-balancing. For example, a battery cell needs to be balanced at the beginning of its life due to inconsistent capacity, and needs to be protected at the end of its life due to excessive self-discharge. At this time, the above scheme will maintain balance throughout the life cycle, which will lead to the risk of misbalancing, which will be detrimental to the stability of the battery, thereby reducing the energy utilization rate of the battery.

In view of the technical problem that the passive battery balancing solution in the prior art easily leads to over-balancing or mis-balancing, the present invention provides a battery balancing control method, and the overall idea is as follows:

Obtain the first parameter and capacity of each battery cell in the battery pack; obtain the minimum capacity and average capacity of the battery pack according to the capacity of each battery cell; obtain the target capacity of the battery pack according to the minimum capacity; determine the target battery cell that meets the preset conditions as the battery cell to be balanced, wherein the preset conditions include: the first parameter of the target battery cell is within the preset balancing mark threshold range, and the capacity of the target battery cell is greater than the average capacity and the target capacity; obtain the balancing time of the battery cell to be balanced according to the capacity of the battery cell to be balanced and the preset balancing current; balance the battery cell to be balanced within the balancing time of the battery cell to be balanced.

Through the above technical solution, the consistency of battery balancing and the effectiveness of the battery cells to be balanced are guaranteed, and over-balancing and mis-balancing are effectively prevented. In addition, while ensuring sufficient balanced power, the consistency differences caused by different factory specifications of batteries and different battery life are reduced, thereby improving the energy utilization of the battery.

Embodiment 1

Referring to FIG. 1 , FIG. 1 is a flow chart of a battery balancing control method of the present invention. In view of the defects of the prior art and the causes of the defects, this embodiment proposes a battery balancing control method, which is applied to the power battery system of a new energy vehicle and is used to control the passive balancing of the power battery charging process so that the voltage deviation of the battery pack is kept within the expected range, thereby ensuring that each single cell maintains the same state during normal use and avoiding overcharging and over-discharging. The method can be directly improved on the basis of the existing hardware of the automotive power battery system.

The battery balancing control method provided by this embodiment is described in detail below in conjunction with FIG. 1 . The method specifically includes the following steps:

Step 101: Obtain the first parameter and capacity of each battery cell in the battery pack.

When a car using a power battery stops running and needs to charge its power battery, the user plugs in the power cord, connects the battery pack to the charging device to start charging, and the battery pack is powered on. At this time, the first parameter and capacity of each cell in the battery pack are collected.

Specifically, there are several groups of battery cells connected in series in the battery pack, and the first parameter and capacity are collected for each individual battery cell, wherein the first parameter can be set according to the actual operating requirements of the power battery. For example, in one implementation, the first parameter of this embodiment may include real-time voltage, real-time temperature, real-time current and other operating parameters, as well as the cooling time or standing time of the battery pack, wherein the standing time may be the time from when the car stops running to when the parameters are collected; in another implementation, the first parameter of this embodiment may include real-time voltage, real-time temperature, real-time current and other operating parameters, as well as the cooling time or standing time of the battery pack, and may also include detection results such as whether there is a fault in the battery pack or whether there is a fault in the balancing circuit.

Capacity (SOC, State of Charge), that is, the state of charge, is used to reflect the remaining capacity of the battery. The capacity cannot be measured directly, and can only be estimated through parameters such as battery terminal voltage, charge and discharge current, and internal resistance. These parameters will also be affected by various uncertain factors such as battery aging, ambient temperature changes, and vehicle driving conditions. Therefore, this implementation calculates the capacity of each battery cell after obtaining the real-time first parameter. The calculation method can adopt traditional calculation methods such as discharge test method, ampere-hour measurement method, battery internal resistance method, open circuit voltage method, load voltage method, etc., or Kalman filtering method, fuzzy logic theory method, neural network method, etc. The specific selection is based on the actual situation of the power battery or the set first parameter.

Step 102: Obtain the minimum capacity and average capacity of the battery pack according to the capacity of each battery cell.

Since the actual capacity of each battery cell is not unique and constant, and will decrease or be consumed with use, when the capacity of all battery cells is collected, the minimum capacity can be obtained, and then the average capacity of the battery pack can be calculated based on the capacity of all battery cells.

Step 103: Obtain a target capacity of the battery pack according to the minimum capacity.

In the specific implementation process, the target capacity can be specifically set according to the specifications of the power battery system. By adopting the target capacity as a benchmark instead of directly using the original capacity or actual capacity of a certain battery cell, the consistency of battery balancing can be ensured to prevent over-balancing of certain batteries with small capacity.

Among them, the target capacitance can be a multiple of the minimum capacitance, or can be set by directly adding a fixed value to the minimum capacitance, and the specific multiple value or added value needs to be set according to the actual situation of the power battery system. For example, the target capacitance can be 1.02 times the minimum capacitance.

Step 104: Determine a target cell that meets a preset condition as a cell to be balanced, wherein the preset condition includes: a first parameter of the target cell is within a preset balancing mark threshold range, and a capacitance of the target cell is greater than the average capacitance and the target capacitance.

Specifically, a single battery cell is taken as a target battery cell, and a preset condition is judged on the target battery cell. First, it is judged whether a first parameter of the target battery cell is within a corresponding preset balance mark threshold range, wherein the preset balance mark threshold range is set according to the actual situation of the power battery system. After the type of the first parameter is determined as mentioned above, the balance mark threshold range is set corresponding to a single parameter in the first parameter; then, it is judged whether the capacity of the target battery cell meets the preset capacity condition, that is, the capacity of the target battery cell is greater than the average capacity and greater than the target capacity.

In one implementation, the target battery cells meeting the preset conditions may be determined as the battery cells to be balanced through the following steps 104.1 to 104.3:

Step 104.1: Determine whether the real-time voltage, real-time temperature, real-time current and rest time of the target battery cell are all within the corresponding preset balance mark threshold range.

In the specific implementation process, after determining that the first parameter includes real-time voltage, real-time temperature, real-time current and standing time, and setting the corresponding balance mark threshold range according to these parameters, the judgment is made, wherein the preset balance mark threshold range corresponding to the first parameter is set according to the actual situation of the power battery system. For example, when the battery pack is a ternary polymer lithium battery, the first parameter of the ternary battery cell in the battery pack is set to include real-time voltage, real-time temperature, real-time current and standing time. Correspondingly, the balance mark threshold corresponding to the voltage of the ternary battery cell can be set to 4.0-4.15V, the balance mark threshold corresponding to the temperature of the ternary battery cell can be set to 10-35°C, the balance mark threshold corresponding to the current of the ternary battery cell can be set to rated current ±3A, the balance mark threshold corresponding to the standing time of the battery pack can be set to 20min or more than 1h, the above conditions are judged for the target battery cell, and step 104.2 is entered.

Step 104.2: When the real-time voltage, real-time temperature, real-time current and rest time of the target battery cell are all within a preset marking threshold range, further determine whether the capacity of the target battery cell is greater than the average capacity and the target capacity.

Specifically, when the real-time voltage, real-time temperature, real-time current and standing time of the target battery cell are all within the preset marking threshold range, it is further determined whether the capacity of the target battery cell is greater than the average capacity and the target capacity; when one of the real-time voltage, real-time temperature, real-time current and standing time of the target battery cell is not within the preset marking threshold range, return to step 101 to continue to obtain the real-time parameters of the battery cell.

Conditionally limiting the target battery cell to the equalization mark threshold range corresponding to the set first parameter can prevent blindly balancing all the batteries, and can also prevent balancing batteries that are not suitable for balancing, thereby preventing misbalancing from occurring.

In the specific implementation process, the real-time voltage, real-time temperature, real-time current and static time of the target battery cell are all within the preset marked threshold range, which means that the threshold ranges corresponding to these parameters are met at the same time. If one of the above parameters of a target battery cell does not meet the threshold range, it means that the target battery cell is not suitable for balancing, and no further judgment is made on it. Then, the next target battery cell is judged within the preset marked threshold range, or the process returns to step 101 to continue to obtain the real-time parameters of the target battery cell until the target battery cell meets the preset standard threshold range, and then further judgment is made.

Specifically, it is further determined whether the capacity of the target battery cell is greater than the average capacity and the target capacity. When the capacity of the target battery cell is greater than the average capacity and less than or equal to the target capacity, or when the capacity of the target battery cell is less than or equal to the average capacity and greater than the target capacity, it is deemed that the capacity determination condition is not met. Only when the capacity of the target battery cell is greater than the average capacity and greater than the target capacity, step 104.3 is entered.

Step 104.3: If the capacitance of the target cell is greater than the average capacitance and greater than the target capacitance, the target cell is determined to be a cell to be balanced.

Specifically, when the capacitance of the target cell is greater than the average capacitance and greater than the target capacitance, the target cell is determined to be a cell to be balanced, and the process proceeds to step 105 ; otherwise, the process returns to step 101 to continue acquiring the real-time parameters of the cell.

The actual capacity of the target cell is used to determine whether it meets the capacity standard set according to its actual capacity, so as to determine the cell to be balanced and ensure the real-time accuracy of the capacity. The standard is set according to the actual situation to prevent the situation where the actual capacity is smaller than the original capacity due to battery loss and other reasons, and the over-balancing situation caused by the unrealistic capacity setting standard can be prevented. This can ensure the effectiveness of the cell to be balanced.

In the specific implementation process, the target cell is determined to be the cell to be balanced, that is, the target cell is marked, indicating that the target cell is the cell that really needs to be balanced, which can prevent the occurrence of misbalancing. Since there are many cells in the battery pack, each single cell is generally numbered. Therefore, marking the target cell can determine that it is the cell to be balanced by determining the number of the target cell, so that when balancing is performed later, the cell corresponding to the number can be directly balanced.

Step 105: Obtaining a balancing time of the battery cell to be balanced according to the capacity of the battery cell to be balanced and a preset balancing current.

Specifically, setting a reasonable balancing time can not only ensure that the battery cells reach sufficient balanced power, but also prevent the battery cells from being balanced all the time during the entire charging or discharging process, which may easily lead to over-balancing.

In the specific implementation process, the balancing power = balancing time * balancing current. In this embodiment, according to this relationship, the balancing time of the battery cell to be balanced is set = the capacity of the battery cell to be balanced / preset balancing current. The balancing time is a comprehensive indicator affected by the hardware circuit and the battery consistency requirements. A reasonable time can prevent over-balancing. The preset balancing current is adjusted according to the strategy requirements of the power battery system and the performance of the power battery. Correspondingly, the balancing time is set specifically for the capacity of the battery cell to be balanced. The balancing time of the batteries that need to be balanced in the entire battery pack may be inconsistent, so that the battery balancing object and balancing time are more targeted.

Step 106: Balancing the battery cells to be balanced within the balancing time of the battery cells to be balanced.

Specifically, in order to reduce the consistency difference caused by different factory specifications of batteries and different battery life, it is necessary to balance the cells to be balanced in the battery pack that meet the conditional restrictions in the above steps. Specifically, balancing is performed according to the existing hardware in the power battery system, including a passive balancing circuit for balancing. As the balancing time decreases, the cells to be balanced are balanced and discharged. After the balancing time ends, the balancing is terminated to ensure sufficient balancing power, improve the battery capacity, and extend the battery life.

In a battery balancing control method provided in this embodiment, the user can retain the original passive balancing design circuit according to the battery consistency difference, and perform passive balancing control under the balancing current and hardware conditions. This embodiment achieves the technical effect of improving the electrical performance difference of a single cell in a battery pack, increasing the battery usage capacity, and extending the battery life. Specifically, the cells whose real-time parameters are within the preset balancing mark threshold range are first screened, and then the cells to be balanced are determined according to the average capacity and the target capacity, which can ensure the effectiveness of the cells to be balanced and effectively avoid misbalancing; and, the target capacity is set according to the minimum capacity, and only the cells greater than the average capacity and greater than the target capacity are balanced, which effectively avoids over-balancing and improves the energy utilization rate of the battery; finally, within the balancing time of the cells to be balanced, the determined cells to be balanced are balanced and discharged, while ensuring sufficient balancing power, reducing the consistency difference caused by different factory specifications and different battery life, so as to maximize the short-term energy of the battery, prevent over-balancing and misbalancing, and effectively ensure that the cell with the smallest capacity in the battery pack achieves capacity maximization within the full life cycle of the battery, thereby maximizing the capacity of the battery pack.

Embodiment 2

Based on the same inventive concept, referring to another flow chart of a battery balancing control method shown in FIG. 2 , this embodiment further provides a battery balancing control method based on the first embodiment, specifically comprising the following steps:

Step 201: Obtain the first parameter and capacity of each battery cell in the battery pack.

Specifically, the battery pack is powered on, and the first parameter and capacity of each battery cell in the battery pack are obtained; in one embodiment, the first parameter includes the real-time voltage, real-time temperature, real-time current and static time of the battery cell;

Step 202: Obtain the minimum capacity and average capacity of the battery pack according to the capacity of each battery cell.

Step 203: Obtain a target capacity of the battery pack according to the minimum capacity.

Step 204: Determine a target cell that meets a preset condition as a cell to be balanced, wherein the preset condition includes: a first parameter of the target cell is within a preset balancing mark threshold range, and a capacity of the target cell is greater than the average capacity and the target capacity.

In one implementation, the target battery cells meeting the preset conditions may be determined as the battery cells to be balanced through the following steps 104.1 to 104.3:

Step 204.1: Determine whether the real-time voltage, real-time temperature, real-time current and rest time of the target battery cell are all within the corresponding preset balance mark threshold range.

Step 204.2: When the real-time voltage, real-time temperature, real-time current and rest time of the target battery cell are all within a preset marking threshold range, further determine whether the capacity of the target battery cell is greater than the average capacity and the target capacity.

Specifically, when the real-time voltage, real-time temperature, real-time current and standing time of the target battery cell are all within the preset marking threshold range, it is further determined whether the capacity of the target battery cell is greater than the average capacity and the target capacity; when one of the real-time voltage, real-time temperature, real-time current and standing time of the target battery cell is not within the preset marking threshold range, return to step 201 to continue to obtain the real-time parameters of the battery cell;

Step 204.3: If the capacitance of the target cell is greater than the average capacitance and greater than the target capacitance, the target cell is determined to be a cell to be balanced.

Specifically, when the capacitance of the target cell is greater than the average capacitance and greater than the target capacitance, the target cell is determined to be a cell to be balanced, and the process proceeds to step 205; otherwise, the process returns to step 201 to continue acquiring the real-time parameters of the cell;

Step 205: Obtaining a balancing time of the battery cell to be balanced according to the capacity of the battery cell to be balanced and a preset balancing current.

For more implementation details in the implementation based on steps 201 to 205 , reference may be made to the description in the implementation based on steps 101 to 105 in Example 1, and for the sake of brevity of the specification, they will not be repeated here.

Step 206: storing the serial numbers and balancing durations of the cells to be balanced.

Specifically, the serial number corresponding to the battery cell to be balanced and the balancing time thereof are stored in a storage device such as a memory or a storage unit based on the power battery system. After the battery cell to be balanced is determined in step 204, the serial number corresponding to the battery cell to be balanced and the balancing time of the battery cell to be balanced calculated in step 205 are stored together until the balancing is completed and cleared when the balancing is exited. This is convenient for calling the information when the balancing is executed and for continuing the balancing after resolving the problem if a system failure or balancing interruption occurs.

After storing the corresponding serial numbers of the cells to be balanced and their balancing durations, the following steps 207 to 208 may be executed in sequence, thereby realizing passive balancing control of the battery during a complete charging process with an interruption; or steps 207 to 208 may be independently executed step branches, thereby realizing independent passive balancing control of multiple cells. When steps 201 to 206 perform balancing marking, steps 207 to 208 perform balancing on the stored cells to be balanced.

Step 207: Balancing the battery cells to be balanced within the balancing time of the battery cells to be balanced.

In one implementation, the following steps 207.1 to 207.3 may be used to achieve balancing of the battery cells to be balanced within the balancing time of the battery cells to be balanced:

Step 207.1: During the balanced discharge of the battery cell to be balanced, if the battery pack is powered off, the current balancing is interrupted, and the serial number and the remaining balancing time corresponding to the battery cell to be balanced are stored.

Specifically, passive balancing is performed during the charging process of the power battery. When the car is no longer charged, the user unplugs the battery pack from the charging device and the battery pack is powered off. At this time, the current balancing has not been completed, so the current balancing is interrupted and the serial number corresponding to the battery cell to be balanced and the remaining balancing time of this balancing are stored. When the remaining balancing time is stored, it will replace the storage time of the battery cell to be balanced that has been stored in the storage device in step 206.

Step 207.2: judging whether the second parameter of the battery cell to be balanced is within a preset balancing execution threshold range according to the stored serial number of the battery cell to be balanced.

Among them, the second parameter is different from the first parameter, and the specific parameters of the second parameter may be less than the first parameter. For example, in one implementation, the first parameter of this embodiment may include working parameters such as real-time voltage, real-time temperature, real-time current, and the cooling time or static time of the battery pack, and the corresponding second parameter may include working parameters such as real-time voltage, real-time temperature, and the like; in another implementation, the first parameter of this embodiment may include working parameters such as real-time voltage, real-time temperature, real-time current, and the cooling time or static time of the battery pack, and may also include detection results such as detecting whether the battery pack has a fault or whether the balancing circuit has a fault, and the corresponding second parameter may include working parameters such as real-time voltage, real-time temperature, and the like, and detection results such as detecting whether the battery pack has a fault or whether the balancing circuit has a fault.

Specifically, in one embodiment, the preset equalization execution threshold range corresponding to the second parameter is set according to the actual situation of the power battery system, and some parameters are less determined. For example, it is no longer necessary to determine whether the standing time meets the requirements. At the same time, the preset equalization execution threshold range of the real-time second parameter is also wider than the preset equalization mark threshold range. For example, the battery pack in the specific implementation details of step 104.1 of embodiment 1 sets the equalization mark threshold corresponding to the temperature of the ternary battery cell to 10-35°C. Here, the equalization execution threshold corresponding to the temperature of the ternary battery cell can be set to 0-50°C corresponding to the equalization mark threshold.

In one embodiment, specifically, judging whether the second parameter of the battery cell to be balanced is within a preset balancing execution threshold range according to the stored serial number of the battery cell to be balanced may include the following steps 207.2.1 to 207.2.2:

Step 207.2.1: When the battery pack is powered on again, the real-time voltage and real-time temperature of the battery cell to be balanced are obtained according to the stored serial number of the battery cell to be balanced;

Specifically, in one embodiment, the second parameter includes two parameters, namely, real-time voltage and real-time temperature. When the user connects the battery pack to the charging device again and starts charging, the battery pack is powered on again, and firstly, the numbers corresponding to the cells to be balanced stored in the storage device are retrieved, and the real-time voltage and real-time temperature of the corresponding cells to be balanced are obtained according to the numbers of the cells to be balanced stored.

When the battery pack is powered on again, balancing can be continued according to the stored information without re-determining the cells to be balanced, which can not only ensure the completeness of the current balancing, but also reduce the steps of re-determining the cells to be balanced, thereby improving the battery balancing efficiency;

Step 207.2.2: Determine whether the real-time voltage and the real-time temperature of the battery cell to be balanced are both within the corresponding preset balancing execution threshold range;

In the specific implementation process, the judgment is made only after it is determined that the second parameter includes the real-time voltage and the real-time temperature, and the corresponding equalization execution threshold range is set according to these parameters. The method of setting the second parameter content and the equalization execution threshold range corresponding to the second parameter can be set by the user himself or by the manufacturer before the car leaves the factory.

Step 207.3: If the stored second parameter of the battery cell to be balanced is within a preset balancing execution threshold range, balancing the battery cell to be balanced according to the stored remaining balancing time of the battery cell to be balanced.

Specifically, when the stored real-time voltage and real-time temperature of the battery cells to be balanced are both within the corresponding preset equalization execution threshold range, the battery cells to be balanced are balanced according to the stored remaining equalization time of the battery cells to be balanced; when one of the stored real-time voltage and real-time temperature of the battery cells to be balanced is not within the preset equalization execution threshold range, return to step 201 to re-acquire the real-time parameters of the battery cells.

Step 208: When the balancing time ends, clear the stored serial numbers corresponding to the cells to be balanced, and terminate the current balancing.

Specifically, according to the existing hardware in the power battery system, including a passive balancing circuit for balancing, balancing is performed. As the balancing time decreases, the battery cells to be balanced are discharged. After the balancing time ends, the balancing is terminated, which can ensure sufficient balancing power, improve the battery capacity, and extend the battery life.

In a battery balancing control method provided in this embodiment, the steps of storing the numbers of the cells to be balanced and the balancing time, and storing the numbers of the cells to be balanced and the remaining balancing time again when the battery pack is powered off are added. When the battery pack is powered on again, balancing can be continued according to the stored information without re-determining the cells to be balanced. At the same time, after the battery pack is powered on again, the second parameter of the stored cells to be balanced is obtained, and it is determined whether the second parameter is within the preset balancing execution threshold range, which can ensure that the current balancing does not affect the normal discharge of the battery, thereby improving the working efficiency of the power battery system.

Embodiment 3

Based on the same inventive concept, referring to a functional module diagram of a battery balancing control system shown in FIG3 , this embodiment provides a battery balancing control system, the system is connected to a power battery system, and performs passive balancing on the charging process of a battery pack in the power battery system, the system comprising:

A parameter acquisition module, used for acquiring a first parameter of each battery cell in the battery pack;

A capacity module, connected to the parameter acquisition module, for obtaining the capacity of each battery cell according to the first parameter of each battery cell, and obtaining the minimum capacity and average capacity of the battery pack according to the capacity of each battery cell;

a target capacity module, connected to the capacity module, and configured to obtain a target capacity of the battery pack according to the minimum capacity;

a balancing marking module, connected to the parameter acquisition module and the target capacity module, for determining a target cell that meets a preset condition as a cell to be balanced, and outputting information corresponding to the cell to be balanced, wherein the preset condition includes: a first parameter of the target cell is within a preset balancing marking threshold range, and a capacity of the target cell is greater than the average capacity and the target capacity;

A balancing time module, connected to the balancing mark module, for obtaining the balancing time of the battery cell to be balanced according to the capacity of the battery cell to be balanced and a preset balancing current;

a balancing execution module, connected to the balancing duration module, and configured to balance the battery cells to be balanced within the balancing duration of the battery cells to be balanced; and further configured to determine whether the second parameter of the battery cells to be balanced is within a preset balancing execution threshold range according to the serial numbers corresponding to the stored battery cells to be balanced, so as to balance the battery cells to be balanced according to the remaining balancing duration of the stored battery cells to be balanced;

The storage module is connected to the balancing time module and the balancing execution module, and is used to store the serial numbers corresponding to the cells to be balanced and their balancing time, and to store the remaining balancing time of the cells to be balanced when balancing is interrupted.

A battery balancing control system provided in this embodiment achieves the technical effects of improving the electrical performance differences of individual battery cells in a battery pack, increasing the battery's usable capacity, and extending the battery life, preventing over-balancing and mis-balancing, and effectively ensuring that the capacity of the battery cell with the smallest capacitance in the battery pack is maximized over the entire life cycle of the battery, thereby maximizing the capacity of the battery pack.

Embodiment 4

Based on the same inventive concept, this embodiment provides a computer-readable storage medium, such as a flash memory, a hard disk, a multimedia card, a card-type memory (for example, an SD or DX memory, etc.), a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a disk, an optical disk, a server, an App application store, etc., on which a computer program is stored. When the computer program is executed by a processor, the following method steps can be implemented:

Step 301: Obtaining first parameters and capacity of each battery cell in the battery pack; the first parameters include real-time voltage, real-time temperature, real-time current and rest time of the battery cell;

Step 302: Obtaining the minimum capacity and average capacity of the battery pack according to the capacity of each battery cell;

Step 303: Obtaining a target capacity of the battery pack according to the minimum capacity;

Step 304: Determine a target cell that meets a preset condition as a cell to be balanced, wherein the preset condition includes: a first parameter of the target cell is within a preset balancing mark threshold range, and a capacity of the target cell is greater than the average capacity and the target capacity;

Step 305: Obtaining a balancing time of the battery cell to be balanced according to the capacity of the battery cell to be balanced and a preset balancing current;

Step 306: Balancing the battery cells to be balanced within the balancing time of the battery cells to be balanced.

The specific implementation process of the above method steps can be found in Example 1, and this embodiment will not be repeated here.

Embodiment 5

Based on the same inventive concept, this embodiment provides an electronic device, which may be a mobile phone, a computer or a tablet computer, etc., including a memory and a processor, wherein a computer program is stored on the memory, and when the computer program is executed by the processor, the battery balancing control method described in the above embodiment 1 is implemented. It can be understood that the electronic device may also include a multimedia component, an input/output (I/O) interface, and a communication component.

The processor is used to execute all or part of the steps in the battery balancing control method described in the first embodiment. The memory is used to store various types of data, which may include instructions of any application or method in the electronic device, and data related to the application.

The processor may be an application specific integrated circuit (ASIC), a digital signal processor (DSP), a digital signal processing device (DSPD), a programmable logic device (PLD), a field programmable gate array (FPGA), a controller, a microcontroller, a microprocessor or other electronic components, and is used to execute all or part of the steps in the battery balancing control method described in the first embodiment.

The memory can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk or optical disk.

The multimedia component may include a screen and an audio component, wherein the screen may be a touch screen, and the audio component is used to output and/or input audio signals. For example, the audio component may include a microphone, and the microphone is used to receive external audio signals. The received audio signal may be further stored in a memory or sent via a communication component. The audio component also includes at least one speaker for outputting audio signals.

The I/O interface provides an interface between the processor and other interface modules, and the other interface modules may be a keyboard, a mouse, buttons, etc. These buttons may be virtual buttons or physical buttons.

The communication component is used for wired or wireless communication between the electronic device and other devices. Wireless communication, such as Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G or 4G, or one or a combination of them, so the corresponding communication component may include: Wi-Fi module, Bluetooth module, NFC module.

The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structures or equivalent process changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly or indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims (8)

1. A battery equalization control method, characterized in that the method comprises the steps of:

acquiring a first parameter and a capacitance of each electric core in the battery pack, wherein the first parameter comprises real-time voltage, real-time temperature, real-time current and standing time;

obtaining the minimum capacitance and the average capacitance of the battery pack according to the capacitance of each battery cell;

obtaining a target capacitance of the battery pack according to the minimum capacitance;

judging whether the real-time voltage, the real-time temperature, the real-time current and the standing time length of the target battery cell are all within the corresponding preset balance mark threshold value range or not;

When the real-time voltage, the real-time temperature, the real-time current and the standing time length of the target battery cell are all within the preset marking threshold value range, further judging whether the capacitance of the target battery cell is larger than the average capacitance and the target capacitance;

If the capacitance of the target battery cell is larger than the average capacitance and larger than the target capacitance, determining the target battery cell as a battery cell to be balanced;

Obtaining the equalization time length of the battery cell to be equalized according to the capacitance of the battery cell to be equalized and preset equalization current;

equalizing the battery cells to be equalized within the equalization time length of the battery cells to be equalized;

wherein, balance the battery cell to be balanced, include:

Acquiring a second parameter of the battery cell to be balanced, wherein the second parameter comprises real-time voltage and real-time temperature;

Judging whether the real-time voltage and the real-time temperature of the battery cell to be balanced are both in a corresponding preset balancing execution threshold range;

And when the real-time voltage and the real-time temperature of the battery cell to be balanced are both in the corresponding preset balanced execution threshold ranges, balancing the battery cell to be balanced according to the residual balanced time length of the battery cell to be balanced.

2. The battery equalization control method of claim 1, wherein after the step of obtaining the equalization duration of the cells to be equalized according to the capacitance of the cells to be equalized and a preset equalization current, the method further comprises:

And storing the number corresponding to the cell to be balanced and the balancing duration thereof.

3. The battery equalization control method according to claim 1, wherein the step of equalizing the battery cells to be equalized in the equalization period of the battery cells to be equalized specifically includes:

and in the process of carrying out balanced discharge on the battery cells to be balanced, if the battery pack is powered down, interrupting the balancing and storing the number corresponding to the battery cells to be balanced and the residual balancing duration.

4. The battery equalization control method as set forth in claim 2 or 3, wherein the step of equalizing the cells to be equalized in the equalization period of the cells to be equalized specifically includes:

in the balancing time length of the battery cells to be balanced, balancing the battery cells to be balanced according to the stored numbers corresponding to the battery cells to be balanced;

The balancing the battery cell to be balanced according to the remaining balancing duration of the battery cell to be balanced comprises the following steps:

And balancing the battery cells to be balanced according to the stored residual balancing duration of the battery cells to be balanced.

5. The battery equalization control method of claim 4, wherein after the step of equalizing the cells to be equalized within an equalization period of the cells to be equalized, the method further comprises:

and when the balance duration time is finished, clearing the stored number corresponding to the battery cell to be balanced, and ending the balance.

6. A battery equalization control system, the system comprising:

The parameter acquisition module is used for acquiring first parameters of each electric core in the battery pack, wherein the first parameters comprise real-time voltage, real-time temperature, real-time current and standing time;

The electric capacity module is connected with the parameter acquisition module and is used for obtaining the electric capacity of each electric core according to the first parameter of each electric core and obtaining the minimum electric capacity and the average electric capacity of the battery pack according to the electric capacity of each electric core;

The target capacitance module is connected with the capacitance module and is used for obtaining the target capacitance of the battery pack according to the minimum capacitance;

The balancing marking module is connected with the parameter acquisition module and the target capacitance module and is used for judging whether the real-time voltage, the real-time temperature, the real-time current and the standing time length of the target battery cell are all in the corresponding preset balancing marking threshold value range, when the real-time voltage, the real-time temperature, the real-time current and the standing time length of the target battery cell are all in the preset marking threshold value range, further judging whether the capacitance of the target battery cell is larger than the average capacitance and the target capacitance, and if the capacitance of the target battery cell is larger than the average capacitance and the target capacitance, determining that the target battery cell is a battery cell to be balanced;

the equalization duration module is connected with the equalization marking module and is used for obtaining the equalization duration of the battery cell to be equalized according to the capacitance of the battery cell to be equalized and the preset equalization current;

The equalization execution module is connected with the equalization duration module and is used for equalizing the battery cells to be equalized in the equalization duration of the battery cells to be equalized; wherein, balance the battery cell to be balanced, include: and acquiring a second parameter of the battery cell to be balanced, wherein the second parameter comprises real-time voltage and real-time temperature, judging whether the real-time voltage and the real-time temperature of the battery cell to be balanced are both in a corresponding preset balanced execution threshold range, and balancing the battery cell to be balanced according to the residual balanced time length of the battery cell to be balanced when the real-time voltage and the real-time temperature of the battery cell to be balanced are both in the corresponding preset balanced execution threshold range.

7. A storage medium having stored thereon a computer program executable by one or more processors to implement the battery equalization control method of any of claims 1 to 5.

8. An electronic device comprising a memory and a processor, wherein the memory has stored thereon a computer program which, when executed by the processor, implements the battery equalization control method of any of claims 1 to 5.