Calibration method and calibration system for state of charge of battery and vehicle

Abstract

The invention provides a battery charge state calibration method and calibration system, a vehicle, computer equipment and a computer readable storage medium. The calibration method comprises the following steps: acquiring real-time charge state data of a battery during a charging period; when the charge state data reaches a preset value, the battery is subjected to pulse charging for a preset time with a preset pulse current; obtaining a current voltage and a calibration voltage of the battery after pulse charging; obtaining current charge state data and calibration charge state data of the battery after pulse charging; and comparing the current voltage with the calibration voltage, and calibrating the state of charge through the calibration value based on the comparison result. According to the invention, the pulse current is increased during the battery charging period, and the charge state of the battery is calibrated through the voltage after pulse charging, so that the calibration precision is prevented from being reduced when the voltage of the battery is in a platform period, the calibration precision of the charge state is improved, and the mileage of the vehicle can be estimated more accurately.

Description

Technical Field

[0001] This invention relates to the field of vehicles, and more particularly to the field of battery systems for new energy vehicles. More specifically, it relates to a method for calibrating the state of charge of a battery, a calibration system, a vehicle using the calibration system, a computer device for implementing the calibration method, and a computer-readable storage medium for performing the calibration method. Background Technology

[0002] In recent years, new energy vehicles have become increasingly common in daily life. These vehicles typically use lithium batteries as their power source. Due to the unique characteristics of lithium batteries, overcharging, over-discharging, and overheating must be avoided during use. For example, over-discharging can cause serious damage to the battery, affecting the performance of the entire battery module and even leading to an explosion. A Battery Management System (BMS) is typically used to control the battery's state, which includes State of Charge (SOC), State of Health (SOH), and State of Power (SOP). Since the BMS's SOH and SOP calculations, as well as its power balancing functions, are all based on the SOC value, the accuracy of SOC calibration is particularly important.

[0003] State of Charge (SOC) typically reflects the ratio of the remaining battery charge to the total usable charge at a given discharge current, usually expressed as a percentage. SOC directly affects the battery's voltage and current. The SOC value ranges from 0 to 1; generally, SOC = 0 indicates a fully discharged battery, and SOC = 1 indicates a fully charged battery.

[0004] Currently, SOC calibration mainly employs methods such as open circuit voltage (OCV), ampere-hour integration, Kalman filtering, and neural network / deep learning. These methods are easily affected by factors such as charge / discharge range and temperature during use, especially for lithium iron phosphate batteries, where SOC calibration accuracy is significantly influenced by environmental factors. Therefore, it is necessary to improve the calibration accuracy of SOC. Summary of the Invention

[0005] The purpose of this invention is to solve the problems existing in the prior art and provide a method for calibrating the state of charge (SOC) of a battery in a cost-effective and reliable manner to improve the calibration accuracy of SOC.

[0006] Therefore, according to one aspect of the present invention, a method for calibrating the state of charge (SOC) of a battery is provided. The calibration method includes: acquiring real-time SOC data of the battery during charging; pulse charging the battery with a preset pulse current for a preset time when the SOC data reaches a preset value; acquiring the current voltage and a calibration voltage of the battery after pulse charging; acquiring the current SOC data and the calibration SOC data of the battery after pulse charging; comparing the current voltage with the calibration voltage; and calibrating the SOC based on the comparison result using a calibration value.

[0007] Based on the above-described technical concept, the present invention may further include any one or more of the following optional forms.

[0008] In some alternative forms, the calibration method includes: comparing the current voltage with the calibration voltage within a preset number of times, and calibrating the state of charge based on the comparison result using the calibration value.

[0009] In some alternative forms, the calibration method includes: within the preset number of times, when the current voltage is greater than the calibration voltage, subtracting the calibration value from the current state of charge data; and within the preset number of times, when the current voltage is less than the calibration voltage, adding the calibration value to the current state of charge data.

[0010] In some alternative forms, the calibration method includes: calculating the difference between the current voltage and the calibration voltage, comparing the calculated difference with the calibration difference, and calibrating the state of charge based on the comparison result using the calibration value.

[0011] In some alternative forms, the calibration method includes: within the preset number of times, if the difference between the current voltage and the calibration voltage is greater than the calibration difference, subtracting the calibration value from the current state of charge data; and within the preset number of times, if the difference between the current voltage and the calibration voltage is less than the calibration difference, adding the calibration value to the current state of charge data.

[0012] According to another aspect of the present invention, a calibration system for the state of charge (SOC) of a battery is provided. The calibration system includes: a first acquisition module configured to acquire real-time SOC data of the battery during charging; a processing module configured to pulse charge the battery with a preset pulse current for a preset time when the SOC data reaches a preset value; a second acquisition module configured to acquire the current voltage and a calibration voltage of the battery after pulse charging; a third acquisition module configured to acquire the current SOC data and the calibration SOC data of the battery after pulse charging; and a calibration module configured to compare the current voltage with the calibration voltage and calibrate the SOC based on the comparison result using a calibration value.

[0013] In some alternative forms, the calibration module includes a timer, the calibration module being configured to: compare the current voltage with the calibration voltage within a preset number of times, and calibrate the state of charge based on the comparison result using the calibration value.

[0014] In some alternative configurations, the calibration module is configured to: calculate the difference between the current voltage and the calibration voltage, compare the calculated difference with the calibration difference, and calibrate the state of charge based on the comparison result using the calibration value.

[0015] In some alternative forms, the calibration difference is in the range of 0.004 to 0.007.

[0016] In some alternative configurations, the processing module is configured to send a power adjustment signal to the charging device and instruct the charging device to adjust the current charging current to the preset pulse current.

[0017] In some alternative forms, the first acquisition module includes a battery management system, and / or the processing module includes a microcontroller or an embedded system, and / or the second acquisition module includes a voltage sensor and an electronic control unit of the battery, and / or the third acquisition module includes a battery management system and an electronic control unit of the battery, and / or the calibration module includes a microcontroller or an embedded system.

[0018] In some alternative configurations, the preset pulse current is in the range of 50A to 100A, and the preset time is in the range of 10s to 40s.

[0019] In some alternative configurations, the preset value is 30%, and the calibration value is in the range of 1% to 2%.

[0020] According to another aspect of the present invention, a vehicle is provided, the vehicle including a battery pack, the battery pack including a plurality of battery modules and a calibration system for the state of charge of the batteries, wherein the calibration system is integrated with the battery management system of the vehicle, and the second acquisition module includes a voltage sensor of the vehicle.

[0021] According to another aspect of the present invention, a computer device is provided, the computer device including a memory, a processor and instructions stored in the memory and executable by the processor, wherein the processor executes the instructions to implement the above-described method for calibrating the state of charge of a battery.

[0022] According to another aspect of the present invention, a computer-readable storage medium is provided having computer-executable instructions stored thereon for performing the above-described method for calibrating the state of charge of a battery.

[0023] This invention calibrates the battery's state of charge by adding a pulse current during battery charging and using the voltage after pulse charging. This prevents the calibration accuracy from decreasing when the battery voltage is at a plateau, improves the calibration accuracy of the state of charge, allows for more accurate estimation of vehicle mileage, further enhances vehicle safety, and improves the user experience. Attached Figure Description

[0024] Other features and advantages of the present invention will be better understood through the following detailed description of optional embodiments in conjunction with the accompanying drawings, wherein:

[0025] Figure 1 A flowchart of a method for calibrating the state of charge of a battery according to an embodiment of the present invention is shown;

[0026] Figure 2 A graph showing the relationship between the current and voltage of a battery and charging time according to an embodiment of the present invention is shown.

[0027] Figure 3 A graph showing the relationship between battery voltage and state of charge data after pulse charging is presented.

[0028] Figure 4 A flowchart of a method for calibrating the state of charge of a battery according to another embodiment of the present invention is shown;

[0029] Figure 5 A flowchart of a method for calibrating the state of charge of a battery according to another embodiment of the present invention is shown;

[0030] Figure 6 A schematic diagram of a battery state-of-charge calibration system according to an embodiment of the present invention is shown; and

[0031] Figure 7 A schematic diagram of a computer device according to an embodiment of the present invention is shown. Detailed Implementation

[0032] The implementation and use of the embodiments are discussed in detail below. However, it should be understood that the specific embodiments discussed are merely illustrative of particular ways of implementing and using the invention, and are not intended to limit the scope of the invention.

[0033] Furthermore, the flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions, and operations of the methods and systems according to various embodiments of the present invention. It should be noted that the functions marked in the boxes may occur in a different order than that shown in the drawings. For example, two consecutively indicated boxes may actually be executed substantially in parallel, or they may sometimes be executed in reverse order, depending on the functions involved.

[0034] New energy vehicles typically use lithium iron phosphate (LFP) batteries as their power source. Compared to other lithium batteries such as ternary lithium batteries, LFP batteries have better material stability, and their battery structure remains largely unchanged during charging and discharging, resulting in higher safety and a longer lifespan. Furthermore, LFP batteries are cheaper due to their lower content of heavy and rare metals. Therefore, LFP batteries are widely used in the new energy field. The inventors discovered that LFP batteries experience a plateau during SOC calibration using methods such as the open-circuit voltage method. During this plateau, the battery's OCV (Open Voltage Characteristic) remains essentially unchanged with SOC, affecting the calibration accuracy. If the ampere-hour integration method is used to calibrate the SOC during this plateau, the calibration accuracy will be affected by the cumulative error of the current sensor, thus reducing the battery's safety performance.

[0035] The following will refer to Figures 1 to 3 This invention describes a method for calibrating the state of charge of a battery according to one embodiment of the present invention.

[0036] A method for calibrating the state of charge of a battery according to an embodiment of the present invention includes the following steps.

[0037] Step S101: Obtain real-time state of charge data of the battery during charging.

[0038] In step S101, the real-time state of charge data of the battery during charging can be obtained through the BMS.

[0039] Step S102: When the state of charge data reaches a preset value, the battery is pulse-charged with a preset pulse current for a preset time.

[0040] In step S102, when the state of charge (OCC) data reaches a preset value, a power adjustment signal can be sent to the charging device (e.g., a charging pile) via an MCU (microcontroller) or embedded system. Based on this power adjustment signal, the charging device adjusts the current charging current to a preset pulse current and pulse-charges the battery with this preset pulse current for a preset time. In some embodiments, the preset value can be 30%, at which point the OCV is in a plateau phase. Furthermore, the preset pulse current can be in the range of 50A to 100A, for example, 60A or 90A, and the preset pulse charging time can be in the range of 10s to 40s, for example, 15s or 30s. It is understood that the values ​​of the preset value, preset pulse current, and preset time are not limited to these and can be changed as needed.

[0041] Step S103: Obtain the current voltage and calibration voltage of the battery after pulse charging.

[0042] In step S103, the current voltage of the battery after pulse charging can be obtained by the existing voltage sensor in the vehicle, and the battery-related parameters of the vehicle, i.e. the battery-related parameters calibrated at the time of vehicle manufacturing, can be found through the battery's electronic control unit (ECU) to obtain the calibrated voltage that the battery should reach after pulse charging for a preset time under a preset pulse current.

[0043] Step S104: Obtain the current state of charge data and calibrated state of charge data of the battery after pulse charging.

[0044] In step S104, the current state of charge data of the battery after pulse charging can be obtained through the BMS, and the calibrated state of charge data corresponding to the battery's calibrated voltage can be obtained by searching the battery-related parameters of the vehicle through the battery's electronic control unit (ECU).

[0045] Step S105: Compare the current voltage with the calibrated voltage, and calibrate the state of charge based on the comparison result using the calibration value.

[0046] In step S105, the current voltage can be compared with the calibrated voltage using an MCU or embedded system, and the state of charge (SOC) can be calibrated based on the comparison result using a calibration value. Specifically, if the current voltage is greater than the calibrated voltage, the calibration value is subtracted from the current SOC data; if the current voltage is less than the calibrated voltage, the calibration value is added to the current SOC data. In some embodiments, the calibration value depends on factors such as system error, battery health, and the sensing accuracy of the voltage sensor. For example, when the voltage sensor has high sensing accuracy, such as 0.1 mV or 0.5 mV, the calibration value can be 1% or 2%. In this case, the BMS can adjust the current SOC data by 1% or 2% based on the comparison result to calibrate the SOC.

[0047] In this way, the present invention increases the pulse current during battery charging and senses the voltage after pulse charging. By comparing the voltage after pulse charging with the calibrated voltage, the state of charge is calibrated to prevent the calibration accuracy from decreasing when the voltage is at a plateau. This improves the calibration accuracy of the state of charge, enabling more accurate estimation of vehicle mileage, further enhancing vehicle safety and improving the user experience.

[0048] In this embodiment, an example is given with a preset value of 30%, a preset pulse current of 60A, and a preset pulse charging time of 15s. Table 1 below illustrates the relationship between the current and the preset pulse charging time and the State of Charge (SOC) during the charging phase. It can be seen that in this embodiment, no pulse current is added when the SOC is between 0% and 30%. From the point the SOC reaches 30%, a pulse current is added during charging. At this time, the battery is charged with a preset pulse current of 60A for 15s. Because the pulse current is relatively small, the SOC changes slowly, and the SOC may be, for example, 30.5%. Therefore, after the pulse charging ends, charging continues with the calibrated charging current (185A when the SOC is between 30% and 35%) until the SOC reaches 35%. This process is repeated until the SOC reaches 80%, at which point no more pulse current is added. It should be noted that after the SOC reaches 80%, the voltage changes more significantly with the SOC; that is, the voltage is no longer in a plateau period, and the calibration accuracy of the SOC is higher at this point. Understandably, pulse current can also be added throughout the battery charging process to further improve the calibration accuracy of the SOC.

[0049] Table 1. Relationship between charging current and preset pulse charging time with SOC during the charging phase.

[0050]

[0051]

[0052] Combination Figure 2 and Figure 3 As shown, A-A1 is the current curve, B-B1 is the voltage curve, and C-C1 is the voltage curve after pulse charging. Figure 2 The O-O1 box shows the current and voltage after a pulsed current is applied during charging. It can be seen that... Figure 2 At point X, the charging current drops from 220A to 60A, indicating that a pulse current has been applied, and the voltage also decreases accordingly. At this point, the SOC is 30%. After 15 seconds of pulse charging, the current voltage is obtained. Figure 2 At point Y, the charging current is increased to 185A, and the voltage also increases accordingly. When the state of charge (SOC) reaches 35%, a pulse current is added again, and the above process is repeated until the SOC reaches 80%. At this point, the charging current is 97A. Figure 2 At point X1 in the diagram, the voltage corresponds to Figure 2 At point Y1 in the above process, the battery voltage after pulse charging at different SOCs is obtained, and the voltage is linearly fitted to obtain the C-C1 curve. It can be seen that the voltage after pulse charging changes linearly and does not plateau; therefore, the state of charge can be calibrated using the voltage after pulse charging. Conversely, the voltage after charging at the rated current, for example... Figure 2 The Z-points and Z1-points in the calibration remain essentially unchanged. This means that if charged according to the rated current, the voltage will plateau when the State of Charge (SOC) is between 30% and 80%, affecting the accuracy of the SOC calibration. It is understood that in this embodiment, the SOC corresponding to the voltage plateau is 30% to 80%, but for different battery models, the SOC corresponding to the voltage plateau may differ; for example, the SOC could be between 20% and 90%, etc., which is not limited here.

[0053] After pulse charging, the current SOC, calibrated SOC, current voltage, and calibrated voltage are acquired. Table 2 below illustrates the relevant data for pulse charging. For example, after pulse charging with a pulse current of 60A for 15 seconds at an SOC of 30%, the calibrated SOC should be 30.31%, and the calibrated voltage should be 3.364645A. The current voltage is compared with the calibrated voltage. If the current voltage is greater than the calibrated voltage, it indicates that the current SOC exceeds 30.31%, and the calibrated value is subtracted from the current SOC. If the current voltage is less than the calibrated voltage, it indicates that the current SOC is less than 30.31%, and the calibrated value is added to the current SOC to calibrate the state of charge.

[0054] Table 2. Relevant data on pulse charging

[0055] SOC Pulse current Pulse time Initial SOC Calibrating SOC Calibration voltage Difference 30％-35％ 60 15 30.00％ 30.31％ 3.364645 35％-40％ 60 15 35.00％ 35.50％ 3.369436 0.004789 40％-45％ 60 15 40.00％ 40.70％ 3.376052 0.006618 45％-50％ 60 15 45.00％ 45.89％ 3.381337 0.005285 50％-55％ 60 15 50.00％ 51.09％ 3.386454 0.005117 55％-60％ 60 15 55.00％ 56.28％ 3.392251 0.005797 60％-65％ 60 15 60.00％ 61.48％ 3.399081 0.00683 65％-70％ 60 15 65.00％ 66.67％ 3.405716 0.006635 70％-75％ 60 15 70.00％ 71.87％ 3.411721 0.006005 75％-80％ 60 15 75.00％ 77.06％ 3.41779 0.006069

[0056] The following will refer to Figure 4 A method for calibrating the state of charge of a battery according to another embodiment of the present invention is described.

[0057] A method for calibrating the state of charge of a battery according to another embodiment of the present invention includes the following steps.

[0058] Step S201: Obtain real-time state of charge data of the battery during charging.

[0059] Step S202: When the state of charge data reaches a preset value, pulse charge the battery with a preset pulse current for a preset time.

[0060] Step S203: Obtain the current voltage and calibration voltage of the battery after pulse charging.

[0061] Step S204: Obtain the current state of charge data and calibrated state of charge data of the battery after pulse charging.

[0062] Step S205: Compare the current voltage with the calibrated voltage within a preset number of times, and calibrate the state of charge based on the comparison result using the calibration value.

[0063] In this embodiment, steps S201 to S204 are the same as in the above embodiment and will not be described again. In step S205, a timer can be set in the MCU or embedded system to compare the current voltage with the calibration voltage within a preset number of times. In some embodiments, the timer can be, for example, a hardware timer or a software-simulated timer, which is not limited here. In addition, the preset number of times can be, for example, 2 times or 3 times. Specifically, if the current voltage is greater than the calibration voltage within the preset number of times, it means that the current state of charge data exceeds the calibration state of charge data. At this time, the calibration value is subtracted from the current state of charge data; if the current voltage is less than the calibration voltage within the preset number of times, it means that the current state of charge data is lower than the calibration state of charge data. At this time, the calibration value is added to the current state of charge data to calibrate the state of charge.

[0064] Since the sensing accuracy of voltage sensors may be affected by factors such as environmental conditions and power supply stability, by comparing the current voltage with the calibrated voltage within a preset number of times, the accuracy of the sensed current voltage can be ensured when the voltage sensor's error fluctuates. This reduces the risk of false calibration caused by error fluctuations, improves system stability, and further enhances the calibration accuracy of the state of charge.

[0065] The following will refer to Figure 5 A method for calibrating the state of charge of a battery according to another embodiment of the present invention is described.

[0066] A method for calibrating the state of charge of a battery according to another embodiment of the present invention includes the following steps.

[0067] Step S301: Obtain real-time state of charge data of the battery during charging.

[0068] Step S302: When the state of charge data reaches a preset value, the battery is pulse-charged with a preset pulse current for a preset time.

[0069] Step S303: Obtain the current voltage and calibration voltage of the battery after pulse charging.

[0070] Step S304: Obtain the current state of charge data and calibrated state of charge data of the battery after pulse charging.

[0071] Step S305: Calculate the difference between the current voltage and the calibrated voltage, compare the calculated difference with the calibrated difference, and calibrate the state of charge based on the comparison result using the calibrated calibration value.

[0072] In this embodiment, steps S301 to S304 are the same as in the above embodiment and will not be repeated. In step S305, the difference between the current voltage and the calibration voltage can be calculated by an MCU or embedded system. The calculated difference is compared with the calibration difference, and the state of charge is calibrated based on the comparison result using a calibration value. The calibration difference is the difference between the voltage sensor output value determined by actual testing at the time of vehicle delivery and the actual value, and is calibrated in the software. In some embodiments, the calibration difference can be in the range of 0.004 to 0.007, for example, 0.005. It is understood that the range of the calibration difference is not limited to this and can be changed as needed.

[0073] Specifically, if the difference between the current voltage and the calibrated voltage is greater than the calibrated difference within a preset number of cycles, it indicates that the current state of charge (SOC) data exceeds the calibrated SOC data. In this case, the calibrated calibration value is subtracted from the current SOC data. If the difference between the current voltage and the calibrated voltage is less than the calibrated difference within a preset number of cycles, it indicates that the current SOC data is lower than the calibrated SOC data. In this case, the calibrated calibration value is added to the current SOC data to calibrate the SOC. For example, when the calibrated difference is 0.005, referring to the difference in Table 2 above, which represents the difference between the current voltage and the calibrated voltage, after pulse charging with a 60A pulse current for 15 seconds at a SOC of 35%, the difference between the current voltage and the calibrated voltage is 0.004789, which is less than 0.005. This indicates that the current SOC is lower than the calibrated SOC. In this case, the calibrated calibration value is added to the current SOC to calibrate the SOC. It should be noted that the difference used when the SOC is 30% to 35% is the same as the difference calculated when the SOC is 35% to 40%. This is because the voltage characteristics are similar when the SOC is 30% to 35% and when the SOC is 35% to 40%. Therefore, using the difference calculated when the SOC is 35% to 40% can save software computing power and improve calibration efficiency.

[0074] In this way, by calculating the difference between the current voltage and the calibrated voltage and comparing the calculated difference with the calibrated difference within a preset number of times, the uncertainty caused by voltage measurement error and voltage sensor error fluctuation can be eliminated, the risk of false calibration can be reduced, the system stability can be improved, and the calibration accuracy of the state of charge can be further improved.

[0075] Reference Figure 6 The present invention also provides a calibration system for the state of charge (SOC) of a battery. The calibration system 100 includes: a first acquisition module 110 configured to acquire real-time SOC data of the battery during charging; a processing module 120 configured to pulse charge the battery with a preset pulse current for a preset time when the SOC data reaches a preset value; a second acquisition module 130 configured to acquire the current voltage and a calibration voltage of the battery after pulse charging; a third acquisition module 140 configured to acquire the current SOC data and the calibration SOC data of the battery after pulse charging; and a calibration module 150 configured to compare the current voltage with the calibration voltage and calibrate the SOC based on the comparison result using a calibration value.

[0076] For the technical effects of the battery state-of-charge calibration system according to this embodiment, please refer to the information on... Figures 1 to 3 The description will not be repeated here.

[0077] In some implementations, the calibration module 150 may be configured to: compare the current voltage with the calibration voltage within a preset number of times, and calibrate the state of charge based on the comparison result using the calibration value.

[0078] For the technical effects of the battery state-of-charge calibration system according to this embodiment, please refer to the information on... Figure 4 The description will not be repeated here.

[0079] In some implementations, the calibration module 150 may be configured to: calculate the difference between the current voltage and the calibration voltage, compare the calculated difference with the calibration difference, and calibrate the state of charge based on the comparison result using a calibration value.

[0080] For the technical effects of the battery state-of-charge calibration system according to this embodiment, please refer to the information on... Figure 5 The description will not be repeated here.

[0081] Reference Figure 7 , Figure 7 This is a schematic diagram of a computer device according to one embodiment of the present invention.

[0082] The present invention also provides a computer device 200, such as Figure 7 As shown, the computer device 200 may include a memory 210 and a processor 220. The memory 210 may store instructions 211, which may be executed by the processor 220. When the processor 220 executes the instructions 211, it implements the battery state of charge calibration method according to the above embodiment.

[0083] The computer device 200 in this embodiment can be a laptop, desktop computer, or cloud server, etc. It is understood that the components included in the computer device 200 are not limited to the memory 210 and processor 220, and can vary depending on different needs. Exemplarily, the computer device 200 may also include multiple components connected to its input / output interfaces (…). Figure 7 (Not shown in the image), including but not limited to: input units, such as keyboards, mice, etc.; output units, such as displays, speakers, etc.; storage units, such as semiconductor storage devices, magnetic surface storage devices, optical storage devices, etc.; and communication units, such as network interface cards, wireless communication transceivers, etc.

[0084] In some implementations, memory 210 may include, for example, random access memory (RAM) or read-only memory (ROM). Memory 210 may be used to store instructions, programs, code, and other programs and data required by the computer device 200, but is not limited thereto.

[0085] In addition, the processor 220 can be a central processing unit (CPU) or other general-purpose processors, such as digital signal processing (DSP), field-programmable gate array (FPGA), programmable logic array (PLA), etc.

[0086] In an exemplary embodiment of the present invention, a computer-readable storage medium is also provided having computer-executable instructions stored thereon for performing a method for calibrating the state of charge of a battery according to the above embodiments.

[0087] Alternatively, the computer-readable storage medium according to this embodiment may be a ROM, RAM, semiconductor storage device, magnetic surface storage device, and optical storage device, etc.

[0088] This invention calibrates the state of charge (SOC) by adding a pulse current during battery charging and using voltage correlation values. This allows for SOC calibration to be completed during vehicle charging, unaffected by voltage plateaus, thus improving calibration accuracy. Furthermore, this invention utilizes the vehicle's existing voltage sensor, eliminating the need for additional hardware. Moreover, the calibration system can be integrated into the Battery Management System (BMS). Therefore, by improving the BMS algorithm, the calibration process of this invention can be implemented, reducing manufacturing costs.

[0089] It should be understood that the embodiments shown in the figures only illustrate an optional configuration of the calibration system for the state of charge of the battery according to the present invention; however, it is only illustrative and not limiting, and other configurations may be adopted without departing from the spirit and scope of the present invention.

[0090] The technical content and features of the present invention have been disclosed above. However, it is understood that those skilled in the art can make various changes and improvements to the disclosed concepts under the inventive concept of the present invention, all of which fall within the protection scope of the present invention. The description of the above embodiments is illustrative rather than restrictive, and the protection scope of the present invention is determined by the claims.

Claims

1. A method for calibrating the state of charge of a battery, characterized in that, The calibration method includes: Acquire real-time state of charge data of the battery during charging (S101; S201; S301); When the state of charge data reaches a preset value, the battery is pulse-charged with a preset pulse current for a preset time (S102; S202; S302). Obtain the current voltage and calibration voltage of the battery after pulse charging (S103; S203; S303); Acquire the current state of charge (SOC) data and calibrated SOC data of the battery after pulse charging (S104; S204; S304); The current voltage is compared with the calibration voltage, and the state of charge is calibrated based on the comparison result using a calibration value (S105).

2. The method for calibrating the state of charge of a battery according to claim 1, characterized in that, The calibration method includes: The current voltage is compared with the calibration voltage within a preset number of times, and the state of charge is calibrated based on the comparison result using the calibration value (S205).

3. The method for calibrating the state of charge of a battery according to claim 2, characterized in that, The calibration method includes: Within the preset number of times, if the current voltage is greater than the calibration voltage, the calibration value is subtracted from the current state of charge data; Within the preset number of times, if the current voltage is less than the calibration voltage, the current state of charge data is added to the calibration value.

4. The method for calibrating the state of charge of a battery according to claim 2, characterized in that, The calibration method includes: Calculate the difference between the current voltage and the calibration voltage, compare the calculated difference with the calibration difference, and calibrate the state of charge based on the comparison result using the calibration value (S305).

5. The method for calibrating the state of charge of a battery according to claim 4, characterized in that, The calibration method includes: Within the preset number of times, if the difference between the current voltage and the calibration voltage is greater than the calibration difference, the calibration value is subtracted from the current state of charge data; Within the preset number of times, if the difference between the current voltage and the calibration voltage is less than the calibration difference, the current state of charge data is added to the calibration value.

6. A calibration system for the state of charge of a battery, characterized in that, The calibration system (100) includes: A first acquisition module (110) is configured to acquire real-time state of charge data of the battery during charging. The processing module (120) is configured to pulse charge the battery with a preset pulse current for a preset time when the state of charge data reaches a preset value; The second acquisition module (130) is configured to acquire the current voltage and calibration voltage of the battery after pulse charging; The third acquisition module (140) is configured to acquire the current state of charge data and the calibrated state of charge data of the battery after pulse charging. A calibration module (150) is configured to compare the current voltage with the calibration voltage and calibrate the state of charge based on the comparison result by a calibration value.

7. The battery state-of-charge calibration system according to claim 6, characterized in that, The calibration module (150) includes a timer and is configured to: compare the current voltage with the calibration voltage within a preset number of times, and calibrate the state of charge based on the comparison result using the calibration value.

8. The battery state-of-charge calibration system according to claim 7, characterized in that, The calibration module (150) is configured to: calculate the difference between the current voltage and the calibration voltage, compare the calculated difference with the calibration difference, and calibrate the state of charge based on the comparison result using the calibration value.

9. The battery state-of-charge calibration system according to claim 8, characterized in that, The calibration difference is in the range of 0.004 to 0.

007.

10. The battery state-of-charge calibration system according to claim 6, characterized in that, The processing module (120) is configured to send a power adjustment signal to the charging device and instruct the charging device to adjust the current charging current to the preset pulse current.

11. The calibration system for the state of charge of a battery according to any one of claims 6 to 10, characterized in that, The first acquisition module (110) includes a battery management system, and / or the processing module (120) includes a microcontroller or an embedded system, and / or the second acquisition module (130) includes a voltage sensor and an electronic control unit of the battery, and / or the third acquisition module (140) includes a battery management system and an electronic control unit of the battery, and / or the calibration module (150) includes a microcontroller or an embedded system.

12. The calibration system for the state of charge of a battery according to any one of claims 6 to 10, characterized in that, The preset pulse current is in the range of 50A to 100A, and the preset time is in the range of 10s to 40s.

13. The calibration system for the state of charge of a battery according to any one of claims 6 to 10, characterized in that, The preset value is 30%, and the calibration value is in the range of 1% to 2%.

14. A vehicle, characterized in that, The vehicle includes a battery pack comprising a plurality of battery modules and a calibration system for the state of charge of the battery according to any one of claims 6 to 13, wherein the calibration system (100) is integrated with the battery management system of the vehicle, and the second acquisition module (130) includes a voltage sensor of the vehicle.

15. A computer device, characterized in that, The computer device (200) includes a memory (210), a processor (220), and instructions (211) stored in the memory (210) and executable by the processor (220), wherein the processor (220) implements the method for calibrating the state of charge of a battery according to any one of claims 1 to 5 when executing the instructions (211).

16. A computer-readable storage medium, characterized in that, The computer-readable storage medium has computer-executable instructions stored thereon for performing a method for calibrating the state of charge of a battery according to any one of claims 1 to 5.

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