Battery cell balance management method and system

Abstract

The invention discloses a battery cell balance management method and system, and belongs to the technical field of battery cell balance management, and the method comprises the steps: S1, designing main monitoring, regional monitoring and individual monitoring, dividing a plurality of groups of batteries in a battery cell into a plurality of groups of regions, and monitoring the divided regions through the main monitoring; s2, setting a difference value between the battery and the regional battery pack; s3, collecting parameters between the plurality of groups of batteries and the regional battery pack; s4, the data collected in the step S3 is compared with the parameters set in the step S2, and when the data collected in the step S3 is larger than or smaller than the parameters set in the step S2, the battery and the battery pack are different; s5, after the difference exists in the step S4, analyzing and calculating the existing difference; s6, after the difference analysis calculation in the step S5 is completed, adjusting the difference between the battery and the battery pack through balance management; balance management in the battery pack is subjected to regional division, so that the pressure during balance management is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery cell balance management, and in particular relates to a battery cell balance management method and system. Background Art

[0002] Battery cell balancing management refers to the use of a series of technologies and methods to achieve a balance in the state of charge (SOC) and voltage between cells in a battery pack to improve the overall performance and safety of the battery. The existing battery cell balancing management can basically meet daily usage needs, but there are still some shortcomings that need to be improved.

[0003] In the balancing management of battery cells, the battery cells in the battery pack are balanced through balancing management. During the balancing management of battery cells, data of several groups of single battery cells are collected, and the collected data are analyzed and calculated. When differences occur in the battery cells, the battery cells are balanced. However, due to the large number of batteries that need to be monitored and collected, the load may be heavy when the battery cells are balanced. For this reason, we propose a battery cell balancing management method and system to solve the above problems. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, the present invention provides a battery cell balancing management method and system.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: A battery cell balance management method, the battery cell management method is as follows: S1. Design main monitoring, regional monitoring and individual monitoring, divide several groups of batteries in the battery cell into several groups of areas, and monitor the divided groups of areas through the main monitoring; S2, setting the difference between the battery and the regional battery group; S3, collecting parameters between several groups of batteries and regional battery groups; S4, comparing the data collected in step S3 with the parameters set in step S2, when the data collected in step S3 is greater than or less than the parameters set in step S2, there is a difference between the battery and the battery pack; S5, after the differences exist in step S4, the differences are analyzed and calculated; S6. After the difference analysis calculation in step S5 is completed, the difference between the battery and the battery pack is adjusted through balancing management.

[0006] As a preferred technical solution of the present invention, in step S1, the area monitoring can be divided according to the physical layout and electrical connection method of the battery.

[0007] As a preferred technical solution of the present invention, the parameters in step S3 include attenuation of battery capacitance, temperature change of the battery, voltage, and a predetermined basic voltage difference between each group of batteries.

[0008] As a preferred technical solution of the present invention, in step S5, the capacitance attenuation, voltage and base voltage difference between each group of batteries are calculated to obtain the average capacitance attenuation, voltage and base voltage difference.

[0009] A battery cell balance management system, the system comprising: Main monitoring: The main monitoring summarizes the data of the battery groups in the divided regional monitoring. After the summary is completed, it is analyzed, calculated and judged. After the difference is determined, the balance management of several groups of areas is carried out; Regional monitoring: Regional monitoring summarizes the data of several groups of batteries in the region, analyzes, calculates and judges after the summary is completed, and performs balancing management on several groups of regions after judging whether there are differences. Regional monitoring will also transmit the data of battery capacitance attenuation, battery temperature change, voltage, and predetermined basic voltage difference between each group of batteries in the region to the main monitoring; Individual monitoring: Single data collection is performed on each group of batteries and the collected data is passed to regional monitoring.

[0010] As a preferred technical solution of the present invention, the main monitoring is provided with a data caching mechanism and a self-diagnosis function, and the data collected by the regional monitoring are summarized, analyzed, calculated and judged, and its own hardware and software are checked regularly.

[0011] As a preferred technical solution of the present invention, a local database is provided in the regional monitoring, and a data preprocessing function is added.

[0012] As a preferred technical solution of the present invention, in addition to transmitting the collected data to the regional monitoring, the individual monitoring performs a simple local analysis on the data, and the sensor of the individual monitoring has a self-calibration function.

[0013] Compared with the prior art, the present invention can achieve the following beneficial effects: The battery cell balancing management method and system are provided with main monitoring, regional monitoring and individual monitoring. Voltage battery data is collected through individual monitoring, and the collected data is transmitted to regional monitoring. Regional monitoring processes, calculates, analyzes and judges the data collected by individual monitoring, and then balances the batteries in the area. The regional monitoring transmits the collected data to the main monitoring, and the main monitoring performs balance management on the voltage, capacitance and other data in the area. By dividing the balance management in the battery pack into regions, the pressure during balance management is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the management method structure of the present invention; Figure 2 It is a schematic diagram of the process structure of the present invention. DETAILED DESCRIPTION

[0015] In order to make the technical means, creative features, and purpose and efficacy of the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work all belong to the protection scope of the present invention. The experimental methods in the following embodiments are conventional methods unless otherwise specified, and the materials and reagents used in the following embodiments are all commercially available unless otherwise specified. Example

[0016] like Figure 1-2 A battery cell balancing management method is shown, and the battery cell management method is as follows: S1. Design main monitoring, regional monitoring and individual monitoring, divide several groups of batteries in the battery cell into several groups of areas, and monitor the divided groups of areas through the main monitoring, poll the regional monitoring data every 10 seconds to ensure timely acquisition of battery status. When dividing the areas, in addition to physical layout and electrical connection, it is also necessary to be close to the thermal characteristics of the battery. Batteries with the same heat dissipation effect can be divided together, and can also be divided according to production date or production batch; Since the main monitoring is set in the core control unit of the battery management system (BMS), it is connected to the central control system of the vehicle or energy storage system to transmit the battery status information to the entire system. The regional monitoring can be divided according to the physical grouping or electrical connection logic of the battery. Each regional monitoring is responsible for the information collection and preliminary processing of the battery in one or more modules. Individual monitoring is directly targeted at each battery cell, and accurate monitoring of a single battery is achieved by installing micro sensors on the battery cell or using built-in detection circuits; S2. Set the difference between the battery and the regional battery pack. At normal temperature, the voltage difference is set to ±0.1V. At -20℃, the voltage drop is obvious, so the voltage difference can be adjusted to ±0.2V. The threshold of the charge cut-off voltage is set at around 4.2V; The discharge cut-off voltage threshold is set between 2.5 and 3.0V; The current threshold is ±15% of the rated current; The high temperature threshold during charging is set at 40-60°C; The low temperature threshold during charging is set to -5 to 5°C; The high temperature threshold during discharge is set at 65-75°C; The low temperature threshold during discharge is set to -20 to -10°C; S3. Collect parameters between several groups of batteries and regional battery groups, including battery capacitance attenuation, battery temperature change, voltage, and a predetermined basic voltage difference between each group of batteries. The sensors that collect data can be accurate to the millivolt level to obtain the most accurate battery status information. At the same time, the current sensor can monitor the current size and direction of the battery during charging and discharging in real time. The temperature sensors are distributed on the batteries and battery groups to ensure that their thermal status can be accurately reflected. S4, comparing the data collected in step S3 with the parameters set in step S2. When the data collected in step S3 is greater than or less than the parameters set in step S2, there is a difference between the battery and the battery pack. When analyzing, the cause of the difference is analyzed. The cause of the difference may be due to manufacturing differences of battery cells, different degrees of aging during use, uneven ambient temperature and other factors. Then, according to the type and size of the difference, a specific mathematical model is used for accurate calculation; S5, after the differences exist in step S4, the differences are analyzed and calculated; S6. After the difference analysis calculation in step S5 is completed, the difference between the battery and the battery group is adjusted through balance management, and the capacitance decay, voltage and basic voltage difference between each group of batteries are calculated to obtain the average capacitance decay, voltage and basic voltage difference.

[0017] A battery cell balance management system, the system comprising: The main monitoring system aggregates the data of the battery groups in the divided regional monitoring. After the aggregation is completed, it performs analysis, calculation and judgment. After determining that there are differences, it performs balancing management on several groups of areas. The main monitoring system is equipped with a data cache mechanism. In the process of summarizing, analyzing, calculating and judging the data of regional monitoring, due to the large amount of data and complex processing, setting up data cache can avoid data loss and improve processing efficiency; The main monitoring system should have a self-diagnosis function and regularly check its own hardware and software. If a fault is found, it can promptly issue an alarm and try to switch to the backup monitoring mode to ensure the normal operation of the battery management system. When performing balancing management, the main monitor can interact with the external devices of the battery pack. When it is determined that the battery pack needs to be charged and balanced, the main monitor sends instructions to the charger to adjust the charging strategy, such as changing the charging current, voltage and other parameters, to achieve more effective battery balancing management; Regional monitoring: Regional monitoring summarizes the data of several groups of batteries in the region, analyzes, calculates and judges after the summary is completed, and performs balancing management on several groups of regions after judging whether there are differences. Regional monitoring will also transmit the data of battery capacitance attenuation, battery temperature change, voltage, and predetermined basic voltage difference between each group of batteries in the region to the main monitoring; Regional monitoring adds a data preprocessing function. Before passing the data to the main monitoring, the data is denoised and digital filtering technology is used to remove high-frequency noise in the collected data, thereby improving the data quality and enabling the main monitoring to receive more accurate original data.

[0018] A local database is set up in the regional monitoring to store the historical data of the batteries in the region. By analyzing the historical data, we can better understand the performance trend of the batteries in the region and provide more references for difference analysis and judgment. When performing balancing management, the regional monitoring interacts directly with the battery balancing circuit in the region. When it is determined that there is a battery voltage difference in the region, the regional monitoring directly controls the balancing circuit to achieve power transfer or voltage regulation between batteries, thereby improving the response speed of balancing management. Individual monitoring: collect single data for each battery group and pass the collected data to regional monitoring; In addition to transmitting the collected data to the regional monitoring, the individual monitoring system also performs simple local analysis on the data. When it detects that the temperature of a battery suddenly rises above a certain threshold, the individual monitoring system can issue a preliminary alarm locally to indicate possible battery abnormalities and quickly transmit the data to the regional monitoring system. The sensors for individual monitoring have a self-calibration function. The sensors are self-calibrated regularly to ensure the accuracy of the data. The voltage sensor is calibrated by an internal reference voltage source, and the temperature sensor is calibrated according to a known standard temperature environment. Individual monitoring adopts a low-power design, which reduces its own power consumption while ensuring the accuracy of data collection. For battery-powered monitoring systems, this extends the battery life and reduces the energy consumption of the battery pack.

[0019] The effects of the above steps are: In the management method and system, a larger battery group is divided into several groups of areas, and the batteries in each group of areas are managed regionally. Then the area is monitored by the main monitoring system, which reduces the pressure of completely managing the batteries in the battery master at one time and increases the pressure of balanced management.

[0020] The above shows and describes the basic principles of the present invention; the main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A battery cell balancing management method, characterized in that: The battery cell management method is as follows: S1. Design main monitoring, regional monitoring and individual monitoring, divide several groups of batteries in the battery cell into several groups of areas, and monitor the divided groups of areas through the main monitoring; S2, setting the difference between the battery and the regional battery group; S3, collecting parameters between several groups of batteries and regional battery groups; S4, comparing the data collected in step S3 with the parameters set in step S2, when the data collected in step S3 is greater than or less than the parameters set in step S2, there is a difference between the battery and the battery pack; S5, after the differences exist in step S4, the differences are analyzed and calculated; S6. After the difference analysis calculation in step S5 is completed, the difference between the battery and the battery pack is adjusted through balancing management.

2. A battery cell balancing management method according to claim 1, characterized in that: In the step S1, the area monitoring may be divided according to the physical layout and electrical connection mode of the battery.

3. A battery cell balancing management method according to claim 1, characterized in that: The parameters in step S3 include the attenuation of battery capacitance, temperature change of the battery, voltage, and a predetermined basic voltage difference between each group of batteries.

4. A battery cell balancing management method according to claim 1, characterized in that: In the step S5, the capacitance decay, voltage and base voltage difference between each group of batteries are calculated, so as to obtain the average capacitance decay, voltage and base voltage difference.

5. A battery cell balance management system, characterized in that: According to a battery cell balancing management method according to any one of claims 1 to 4, the system comprises: Main monitoring: The main monitoring summarizes the data of the battery groups in the divided regional monitoring. After the summary is completed, it is analyzed, calculated and judged. After the difference is determined, the balance management of several groups of areas is carried out; Regional monitoring: Regional monitoring summarizes the data of several groups of batteries in the region, analyzes, calculates and judges after the summary is completed, and performs balancing management on several groups of regions after judging whether there are differences. Regional monitoring will also transmit the data of battery capacitance attenuation, battery temperature change, voltage, and predetermined basic voltage difference between each group of batteries in the region to the main monitoring; Individual monitoring: Single data collection is performed on each group of batteries and the collected data is passed to regional monitoring.

6. A battery cell balance management system according to claim 5, characterized in that: The main monitoring system is provided with a data caching mechanism and a self-diagnosis function, and summarizes, analyzes, calculates and judges the data collected by the regional monitoring system, and regularly checks its own hardware and software.

7. A battery cell balance management system according to claim 5, characterized in that: The regional monitoring is provided with a local database and an additional data preprocessing function.

8. A battery cell balance management system according to claim 5, characterized in that: In addition to transmitting the collected data to the regional monitoring, the individual monitoring performs a simple local analysis on the data, and the sensor of the individual monitoring has a self-calibration function.

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