Intelligent heating control method and system for battery pack

Abstract

The invention discloses a battery pack intelligent heating control method and system, and the method comprises the following steps: a BMS obtains the current cell temperature, and sends a request to an inverter based on the comparison result of the current cell temperature and a temperature threshold value; after the inverter receives the request, the power grid and / or the photovoltaic module are / is used for supplying power to the battery cell; the BMS provides a heating current for the battery cell by closing the heating relay, and the inverter obtains a heating current value and feeds back the heating current value to the BMS; and the BMS obtains the temperature value of the battery cell, and the BMS adjusts the magnitude of the heating current based on the obtained temperature value and the heating current value. The actual temperature and electric quantity condition of the battery are obtained through the BMS, the power grid or the photovoltaic module is controlled to adjust the heating current of the battery, and the stability of the working temperature of the battery is improved.

Description

Technical Field

[0001] The present application relates to the technical field of battery management systems, and in particular to a battery pack intelligent heating control method and system. Background Art

[0002] In cold environments, the electrochemical reaction efficiency of secondary batteries such as lithium batteries will be significantly reduced, resulting in slower charging speed, reduced discharge capacity, and may have a negative impact on battery life.

[0003] However, the existing heating control method cannot take into account the real-time power and temperature values ​​of the battery cell, and is not very safe. Summary of the invention

[0004] To solve the above problems, the present application discloses a battery pack intelligent heating control method, which obtains the actual temperature and power status of the battery through the BMS, controls the power grid or photovoltaic module to adjust the heating current of the battery, and improves the stability of the battery operating temperature. At the same time, a battery pack intelligent heating control system is provided, which can apply the above-mentioned battery pack intelligent heating control method.

[0005] The first technical solution adopted in this application is: providing a battery pack intelligent heating control method, comprising the following steps:

[0006] The BMS obtains the current battery cell temperature, and the BMS sends a request to the inverter based on a comparison result between the current battery cell temperature and a temperature threshold;

[0007] After receiving the request, the inverter uses the grid and / or photovoltaic modules to power the battery cells;

[0008] The BMS provides heating current to the battery cell by closing the heating relay, and the inverter obtains the heating current value and feeds it back to the BMS;

[0009] The BMS obtains the temperature value of the battery cell, and adjusts the magnitude of the heating current based on the obtained temperature value and the heating current value.

[0010] Among them, the temperature threshold includes a discharge temperature threshold and a charge temperature threshold; if the battery cell is in a discharge state, the current battery cell temperature is compared with the discharge temperature threshold; if the battery cell is in a charge state, the current battery cell temperature is compared with the charge temperature threshold.

[0011] Among them, it is characterized in that the BMS can obtain the power of the battery cell, and the BMS compares the power of the battery cell with the minimum heating power, and determines whether the battery cell can be heated based on the comparison result.

[0012] The BMS continuously obtains the heating current value, and if the duration of not obtaining the heating current value is greater than a threshold time, the heating process is terminated.

[0013] The BMS obtains the temperature values ​​of all cells in the battery pack, and if the temperature value of a single cell is greater than a safety temperature threshold, the heating process is terminated.

[0014] The BMS obtains the power values ​​of all cells in the battery pack, and if the power of a single cell is greater than a maximum power threshold, the heating process is terminated.

[0015] The second technical solution adopted in this application is to provide a battery pack intelligent heating control system, including:

[0016] BMS, used to monitor the temperature, power, and charge / discharge status of the cells in the battery pack;

[0017] The inverter receives the heating request from the BMS and decides whether to perform heating based on the status of the grid and the PV modules;

[0018] The heating relay is controlled by the BMS and is used to control the on and off of the heating current.

[0019] Wherein, the battery pack intelligent heating control system also includes a recording module, based on which the working parameters of the heating process are recorded.

[0020] The third technical solution adopted in the present application is: an electronic device is provided, which includes: a memory and a processor coupled to each other, and the processor is used to execute program instructions stored in the memory to implement the battery pack intelligent heating control method as described in any of the above items.

[0021] The fourth technical solution adopted in the present application is: providing a computer-readable storage medium, wherein the computer-readable storage medium stores program data, and the program data can be executed by a processor to implement the battery pack intelligent heating control method as described in any one of the above items.

[0022] Beneficial effects of the present application: Different from the prior art, the present application discloses a battery pack intelligent heating control method and system, wherein the battery pack intelligent heating control method includes the following steps: BMS obtains the current battery cell temperature, and BMS sends a request to the inverter based on the comparison result between the current battery cell temperature and the temperature threshold; after receiving the request, the inverter uses the power grid and / or photovoltaic module to power the battery cell; BMS provides heating current to the battery cell by closing the heating relay, and the inverter obtains the heating current value and feeds it back to BMS; BMS obtains the temperature value of the battery cell, and BMS adjusts the size of the heating current based on the obtained temperature value and heating current value. The actual temperature and power status of the battery are obtained by BMS, and the power grid or photovoltaic module is controlled to adjust the heating current of the battery, thereby improving the stability of the battery operating temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] in:

[0025] Figure 1 A schematic diagram of a flow chart of an embodiment of a battery pack intelligent heating control method provided in the present application;

[0026] Figure 2 A schematic diagram of the structure of an embodiment of a battery pack intelligent heating control system provided in this application;

[0027] Figure 3 This is a schematic diagram of the structure of an embodiment of a computer device of the present application;

[0028] Figure 4 This is a schematic diagram of the structure of an embodiment of a computer-readable storage medium of the present application. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It will be appreciated that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some but not all structures related to the present application are shown in the drawings. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the art without making creative work are within the scope of protection of the present application.

[0030] The terms "first", "second", etc. in this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0031] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0032] The present application provides a battery pack intelligent heating control method and system thereof. The battery pack intelligent heating control method can provide appropriate heating current to the battery through the power grid or photovoltaic module according to the actual temperature and power of the battery, thereby maintaining the operating temperature of the battery within a safe and effective range, such as Figure 1 As shown, Figure 1 The flowchart of an embodiment of the battery pack intelligent heating control method provided in this application includes the following steps:

[0033] Step S11: BMS (battery management system) obtains the current battery cell temperature, and sends a request to the inverter based on the comparison result between the current battery cell temperature and the temperature threshold; BMS monitors the temperature of each battery cell regularly or in real time, and can obtain the temperature of the battery cells in the battery pack through the temperature sensor. In order to facilitate BMS to identify the temperature values ​​of different battery cells, each battery cell has a corresponding serial number; BMS compares the measured temperature with the preset temperature threshold; if the battery cell temperature is lower than the set threshold, BMS will determine that the battery cell needs to be heated and send a heating request to the inverter.

[0034] By continuously monitoring the battery cell temperature, it is possible to accurately determine when heating needs to be initiated, avoiding unnecessary energy consumption; preventing the battery cell from operating at too low a temperature, reducing performance degradation and potential damage caused by low temperature.

[0035] Step S12: After receiving the request, the inverter uses the grid and / or photovoltaic modules to power the battery cells; after receiving the heating request from the BMS, the inverter will evaluate the current grid status and the availability of the photovoltaic modules; based on the evaluation results, the inverter selects the most suitable power source (such as the grid, photovoltaics, or a combination of the two) to provide the power required for heating. It should be clear that the priority of grid power supply and photovoltaic power supply is not limited here. For example, in one embodiment, when both the grid and photovoltaics are available, photovoltaic modules are used for power supply first.

[0036] The best power source can be selected according to actual conditions, which not only ensures the heating effect but also improves the flexibility and adaptability of the system; when one power source is unavailable, the system can switch to another power source, enhancing the stability and reliability of the entire system.

[0037] Step S13: BMS provides heating current to the battery cell by closing the heating relay, and the inverter obtains the heating current value and feeds it back to the BMS; after determining the power supply, the BMS closes the heating relay to form a path for the heating circuit, thereby providing heating current to the battery cell; the inverter continuously monitors the size of the heating current and feeds this information back to the BMS for subsequent regulation.

[0038] The heating request is executed immediately after it is received, which reduces the waiting time and quickly increases the battery cell temperature. Through the feedback mechanism, the BMS can understand the current situation during the heating process in real time to ensure the safety and effectiveness of the heating operation.

[0039] Step S14: BMS obtains the temperature value of the battery cell, and adjusts the heating current based on the obtained temperature value and heating current value; BMS continues to monitor the temperature change of the battery cell, and refers to the actual value of the heating current; based on the latest temperature and current information, BMS dynamically adjusts the heating current to maintain the battery cell within an ideal temperature range; automatically adjusts the heating intensity according to actual needs to avoid overheating or insufficient heating, ensuring that the battery cell is always in the best working condition; through dual monitoring of temperature and current, abnormal conditions can be discovered in time, and measures can be taken quickly to ensure system safety.

[0040] In summary, the intelligent heating control method of the battery pack of this embodiment includes the following steps: BMS obtains the current battery cell temperature, and BMS sends a request to the inverter based on the comparison result between the current battery cell temperature and the temperature threshold; after receiving the request, the inverter uses the power grid and / or photovoltaic module to power the battery cell; BMS provides heating current to the battery cell by closing the heating relay, and the inverter obtains the heating current value and feeds it back to BMS; BMS obtains the temperature value of the battery cell, and BMS adjusts the size of the heating current based on the obtained temperature value and heating current value. The actual temperature and power status of the battery are obtained through BMS, and the power grid or photovoltaic module is controlled to adjust the heating current of the battery, thereby improving the stability of the battery operating temperature.

[0041] Optionally, the temperature threshold includes a discharge temperature threshold and a charge temperature threshold; if the battery cell is in a discharge state, the current battery cell temperature is compared with the discharge temperature threshold; if the battery cell is in a charge state, the current battery cell temperature is compared with the charge temperature threshold; the discharge temperature threshold refers to the minimum safe operating temperature that the battery cell should maintain in the discharge state. If the battery cell temperature is lower than this threshold, it may lead to reduced discharge efficiency, reduced capacity, and even irreversible damage to the battery; the charge temperature threshold refers to the minimum safe operating temperature that the battery cell should maintain in the charge state. Low-temperature charging may cause lithium ions to deposit on the electrode surface, which will not only reduce the battery capacity, but also may cause safety hazards, such as internal short circuits.

[0042] When the BMS detects that the battery cell is in a discharge state, it compares the current battery cell temperature with the preset discharge temperature threshold. If the current temperature is lower than the discharge temperature threshold, the BMS will start the heating process to ensure that the battery cell is discharged within a safe temperature range.

[0043] When the BMS detects that the battery cell is in a charging state, it will compare the current battery cell temperature with the preset charging temperature threshold. If the current temperature is lower than the charging temperature threshold, the BMS will also start the heating process to ensure that the battery cell is charged within a safe temperature range.

[0044] By setting the discharge and charge temperature thresholds separately, it can be ensured that the battery is in the optimal temperature range during each charge and discharge process, thereby optimizing the charge and discharge cycle and improving the overall performance of the battery; setting different temperature thresholds according to different states can make heating control more precise, avoid unnecessary heating operations, and save energy.

[0045] Optionally, the BMS can obtain the power of the battery cell, compare the power of the battery cell with the minimum heating power, and determine whether the battery cell can be heated based on the comparison result; the BMS monitors the power status of each battery cell regularly or in real time. This is usually done by measuring parameters such as the voltage, current and temperature of the battery cell to estimate the remaining power (SOC) of the battery cell. The minimum heating power refers to the minimum power level that the battery cell must maintain in order to safely start the heating process; the specific value of the minimum heating power is not limited here, for example, the specific value of the minimum heating power is 20% of the rated capacity. In other embodiments, the minimum heating circuit can take other values, which are not limited here.

[0046] The following describes in detail the comparison process between the battery cell power and the minimum heating power:

[0047] If the battery cell power is higher than or equal to the minimum heating power, the BMS will consider that the battery cell has enough energy for heating and continue the heating process.

[0048] If the battery cell power is lower than the minimum heating power, the BMS will determine that the battery cell power is insufficient and suspend or terminate the heating operation to prevent the battery cell from over-discharging.

[0049] By obtaining the battery power through the BMS and comparing it with the minimum heating power, the battery can be effectively prevented from over-discharging during the heating process, protecting the battery health and extending its service life. At the same time, this method can also improve system safety, optimize energy management, and enhance user experience.

[0050] Optionally, the BMS continuously obtains the heating current value. If the duration of not obtaining the heating current value is greater than the threshold time, the heating process is terminated; the BMS will continuously check whether the heating current value can be received. If the heating current value is not received within a continuous period of time, the BMS will consider that the heating circuit may be faulty or abnormal; once the duration of not obtaining the heating current value exceeds the set threshold time, the BMS will take measures to end the heating process. For example, in this embodiment, the threshold time is 2s, and in other embodiments, the threshold time can be other values, which are not limited here.

[0051] If the heating current is interrupted but the heating process is not terminated in time, energy may be wasted. By setting the threshold time, the BMS can ensure that heating stops immediately when the heating current is interrupted, saving energy. The heating process can be interrupted by disconnecting the heating relay, stopping the supply of heating current, and preventing overheating or other safety hazards caused by heating circuit failure.

[0052] Optionally, the BMS obtains the temperature values ​​of all cells in the battery pack. If the temperature value of a single cell is greater than the safety temperature threshold, the heating process ends; when the cell temperature of a single cell is greater than the temperature threshold, the heating process starts; the temperature of other cells in the battery pack will also rise, which can easily cause thermal runaway if not controlled. The BMS will compare the current temperature of each cell with the preset safety temperature threshold; if the temperature of any cell exceeds the safety temperature threshold, the BMS will consider that the cell has entered a dangerous state, and the BMS will immediately disconnect the heating relay and stop the supply of heating current to prevent the cell temperature from further rising.

[0053] It should be clarified that the present application does not limit the specific values ​​of the safety temperature threshold, the discharge temperature threshold and the charging temperature threshold; however, the safety temperature threshold must be greater than the discharge temperature threshold and the charging temperature threshold; the discharge temperature threshold and the charging temperature threshold may be the same or different, and no limitation is imposed on this.

[0054] By continuously monitoring the temperature of each battery cell, the BMS can detect temperature anomalies at the first opportunity and take prompt action. This rapid response mechanism helps improve the overall reliability of the system and reduce downtime caused by temperature issues.

[0055] Optionally, the BMS obtains the charge values ​​of all the cells in the battery pack. If the charge of a single cell is greater than a maximum charge threshold, the heating process is terminated. The maximum charge threshold refers to the maximum safe charge level that the cell should maintain during the charging and discharging process to ensure that the cell does not pose a safety hazard due to overcharging. The maximum charge threshold can be set between 90% and 95% of the rated capacity of the cell to leave a certain safety margin to prevent the cell from entering an overcharged state.

[0056] Even if most of the cells in the battery pack are charged normally, a single cell with too high a charge may cause problems. By monitoring the charge of all cells, the safety of the entire battery pack can be ensured, avoiding the risks of partial overcharging.

[0057] like Figure 2 As shown, Figure 2 A structural schematic diagram of an embodiment of a battery pack intelligent heating control system provided in the present application includes: a BMS, an inverter and a heating relay.

[0058] BMS is used to monitor the temperature, power, and charge / discharge status of the cells in the battery pack;

[0059] The inverter is used to receive heating requests from the BMS components and decide whether to perform heating based on the status of the grid and the photovoltaic module;

[0060] The heating relay is controlled by the BMS and is used to control the on and off of the heating current.

[0061] Optionally, the battery pack intelligent heating control system also includes a recording module (not shown), which records the working parameters of the heating process based on the recording module. The working parameters include but are not limited to: temperature data, power data, current data, voltage data and timestamp.

[0062] For the above embodiment, the present application provides a computer device, see Figure 3 , Figure 3 This is a schematic diagram of the structure of an embodiment of a computer device of the present application. The computer device includes a memory and a processor, wherein the memory and the processor are coupled to each other, the memory stores program data, and the processor is used to execute the program data to implement the steps of any embodiment of the above-mentioned battery pack intelligent heating control method.

[0063] In this embodiment, the processor may also be referred to as a CPU (Central Processing Unit). The processor may be an integrated circuit chip having signal processing capabilities. The processor may also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0064] The method of the above embodiment can be implemented in the form of a computer program, so the present application proposes a computer readable storage medium, see Figure 4 , Figure 4 This is a schematic diagram of the structure of an embodiment of a computer-readable storage medium of the present application. The computer-readable storage medium stores program data that can be run by a processor, and the program data can be executed by the processor to implement the steps of any embodiment of the above-mentioned battery pack intelligent heating control method.

[0065] The computer-readable storage medium in this embodiment may be a medium that can store program data, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, or may be a server that stores the program data. The server may send the stored program data to other devices for execution, or may execute the stored program data by itself.

[0066] In the several embodiments provided in this application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device implementation described above is only illustrative, for example, the division of the modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0067] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0068] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0069] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A battery pack intelligent heating control method, characterized in that: The steps include: The BMS obtains the current battery cell temperature, and the BMS sends a request to the inverter based on a comparison result between the current battery cell temperature and a temperature threshold; After receiving the request, the inverter uses the grid and / or photovoltaic modules to power the battery cells; The BMS provides heating current to the battery cell by closing the heating relay, and the inverter obtains the heating current value and feeds it back to the BMS; The BMS obtains the temperature value of the battery cell, and adjusts the magnitude of the heating current based on the obtained temperature value and the heating current value.

2. The battery pack intelligent heating control method according to claim 1, characterized in that: The temperature threshold includes a discharge temperature threshold and a charge temperature threshold; if the battery cell is in a discharge state, the current battery cell temperature is compared with the discharge temperature threshold; if the battery cell is in a charge state, the current battery cell temperature is compared with the charge temperature threshold.

3. The battery pack intelligent heating control method according to claim 2, characterized in that: The BMS may obtain the power of the battery cell, compare the power of the battery cell with the minimum heating power, and determine whether the battery cell can be heated based on the comparison result.

4. The battery pack intelligent heating control method according to claim 3, characterized in that: The BMS continuously obtains the heating current value, and if the duration of not obtaining the heating current value is greater than a threshold time, the heating process is terminated.

5. The battery pack intelligent heating control method according to claim 4, characterized in that: The BMS obtains the temperature values ​​of all cells in the battery pack. If the temperature value of a single cell is greater than a safety temperature threshold, the heating process is terminated.

6. The battery pack intelligent heating control method according to claim 5, characterized in that: The BMS obtains the power values ​​of all the cells in the battery pack. If the power of a single cell is greater than the maximum power threshold, the heating process is terminated.

7. A battery pack intelligent heating control system, characterized in that: include: BMS, used to monitor the temperature, power, and charge / discharge status of the cells in the battery pack; The inverter receives the heating request from the BMS and decides whether to perform heating based on the status of the grid and the PV modules; The heating relay is controlled by the BMS and is used to control the on and off of the heating current.

8. The battery pack intelligent heating control system according to claim 7, characterized in that: The battery pack intelligent heating control system also includes a recording module, based on which the working parameters of the heating process are recorded.

9. An electronic device, characterized in that: The electronic device comprises: a memory and a processor coupled to each other, wherein the processor is used to execute program instructions stored in the memory to implement the battery pack intelligent heating control method as described in any one of claims 1-6.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores program data, and the program data can be executed by a processor to implement the battery pack intelligent heating control method as described in any one of claims 1-6.

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