SOC correction methods, battery modules and electronic devices

Abstract

This application provides a SOC correction method, a battery module, and an electronic device. The SOC correction method includes acquiring battery charging parameters, including displayed SOC and battery voltage, in each operating cycle; determining the target SOC of the battery when the charging parameters meet preset conditions; determining an SOC correction coefficient based on the target SOC and the displayed SOC; updating the displayed SOC based on the SOC correction coefficient, and displaying the updated displayed SOC. The SOC correction method provided by this application can effectively improve the accuracy of battery SOC display.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a SOC correction method, a battery module, and an electronic device. Background Technology

[0002] The State of Charge (SOC) of a battery is a crucial parameter describing its operating state, typically expressed as the ratio of remaining charge to actual battery capacity. Users can use SOC to determine the remaining charge of energy storage products or electronic devices. However, existing SOC calculation methods have inherent errors, especially at the end of the charging and discharging process, where these errors are amplified, leading to sudden changes in SOC or prolonged periods of instability. This results in low accuracy and significantly degrades the user experience. Summary of the Invention

[0003] In view of this, this application provides a SOC correction method, a storage medium, a control circuit, and an electronic device to solve the above problems.

[0004] This application provides a SOC correction method, comprising: acquiring battery charging parameters in each operating cycle, the charging parameters including displayed SOC and battery voltage; determining a target SOC of the battery when the battery charging parameters meet preset conditions; determining an SOC correction coefficient based on the target SOC and the displayed SOC; updating the displayed SOC based on the SOC correction coefficient, and displaying the updated displayed SOC. This solution acquires battery charging parameters in each operating cycle, and when the battery charging parameters meet preset conditions, determines a target SOC close to the actual SOC of the battery, determines a corresponding SOC correction coefficient based on the target SOC, and updates the displayed SOC using the SOC correction coefficient, so that the displayed SOC change trend follows the actual SOC change. Thus, the SOC correction method provided by this application can make the corrected SOC change more consistent with the actual SOC change trend, thereby avoiding sudden SOC changes or prolonged inactivity at the end of charging and effectively improving the SOC display accuracy of the battery.

[0005] In one embodiment, when the battery charging parameters meet preset conditions, the target SOC of the battery is determined, including: when the displayed SOC is greater than or equal to the preset SOC and the battery voltage is less than a first voltage threshold, the preset SOC is determined as the target SOC.

[0006] In one embodiment, the SOC correction method further includes: determining the charging mode of the battery; and determining a preset SOC and a first voltage threshold corresponding to the preset SOC based on the charging mode.

[0007] In one embodiment, when the battery charging parameters meet preset conditions, determining the target SOC of the battery includes: when the battery voltage is greater than or equal to a first voltage threshold, determining the target SOC of the battery based on the battery voltage and the battery charging mode.

[0008] In one embodiment, determining the target SOC of the battery based on the battery voltage and the battery charging mode includes: when the charging mode is a first charging mode, acquiring the battery charging current; determining the target SOC based on the charging current and the battery voltage; or when the charging mode is a second charging mode, determining the target SOC based on the battery voltage and a preset mapping relationship; wherein the charging current in the first charging mode is greater than the charging current in the second charging mode.

[0009] In one embodiment, determining the SOC correction coefficient based on the target SOC and the displayed SOC includes: calculating the difference between the target SOC and the displayed SOC to obtain a first SOC difference; calculating the difference between the SOC when the battery is fully charged and the target SOC to obtain a second SOC difference; determining an adjustment step size based on the first SOC difference and the second SOC difference; wherein the adjustment step size is positively correlated with the first SOC difference and negatively correlated with the second SOC difference; and calculating the sum of the initial correction coefficient and the adjustment step size to obtain the SOC correction coefficient.

[0010] In one implementation, updating the displayed SOC based on the SOC correction factor includes: calculating the SOC change of the battery during the operating cycle; determining a target SOC change based on the SOC correction factor and the SOC change; and updating the displayed SOC based on the target SOC change.

[0011] In one embodiment, the SOC correction method further includes: limiting the displayed SOC to not be greater than a preset SOC threshold when the battery voltage is less than a second voltage threshold; or updating the displayed SOC to the SOC when the battery voltage is greater than or equal to the second voltage threshold; wherein the preset SOC threshold is less than the SOC when the battery is fully charged.

[0012] A second aspect of this application provides a battery module, including a battery, a processor, and a memory, wherein the memory includes one or more computer instructions. The one or more computer instructions are executed by the processor to implement the SOC correction method described in any of the preceding claims.

[0013] A third aspect of this application provides an electronic device including the battery module described above.

[0014] The SOC correction method provided in this application introduces a target SOC that is close to the actual SOC after the battery charging parameters meet preset conditions. A corresponding SOC correction coefficient is determined based on the target SOC, and the displayed SOC is updated using this correction coefficient. This ensures that the displayed SOC change trend follows the actual SOC change. Therefore, the SOC correction method provided in this application makes the corrected SOC change more consistent with the actual SOC change trend, thereby avoiding sudden SOC changes or prolonged periods of inactivity at the end of charging and effectively improving the accuracy of the battery's SOC display. Attached Figure Description

[0015] Figure 1 This is a schematic diagram showing the SOC curve of an existing battery.

[0016] Figure 2 This is a schematic diagram showing the SOC curve of another existing battery.

[0017] Figure 3 A structural block diagram of a battery module for applying the SOC correction method of this application.

[0018] Figure 4 This is a flowchart illustrating a SOC correction method provided in an embodiment of this application.

[0019] Figure 5 As shown in one embodiment of this application Figure 4 The flowchart shows the specific steps of step S430.

[0020] Figure 6 As shown in one embodiment of this application Figure 4 The flowchart shows the specific steps of step S440.

[0021] Figure 7a This is a schematic diagram of the SOC curves before and after the SOC correction method provided in an embodiment of this application for battery application in fast charging mode.

[0022] Figure 7b This is a schematic diagram of the SOC curves before and after the SOC correction method provided in an embodiment of this application for battery application in slow charging mode.

[0023] Figure 7c This is a schematic diagram of the SOC curves before and after the SOC correction method provided in an embodiment of this application for battery applications in low-current charging mode.

[0024] Figure 8a A schematic diagram showing the change in battery voltage over time during fast charging mode.

[0025] Figure 8b A schematic diagram showing the change of charging current over time in fast charging mode.

[0026] Figure 9 A schematic diagram showing the change in battery voltage over time during charging in low-current mode.

[0027] Figure 10a This is a schematic diagram of the SOC curves before and after the SOC correction method provided in another embodiment of this application for battery application in fast charging mode.

[0028] Figure 10b This is a schematic diagram of the SOC curves before and after the SOC correction method provided in another embodiment of this application is applied to the battery in slow charging mode.

[0029] Figure 10c This is a schematic diagram of the SOC curves before and after the SOC correction method provided in another embodiment of this application for battery applications in low current mode.

[0030] Figure 11 This is a functional block diagram of a battery module provided in one embodiment of this application.

[0031] Figure 12 This is a structural block diagram of an electronic device provided in an embodiment of this application.

[0032] Explanation of main component symbols

[0033] 10—Battery module; 11—Battery management system (BMS); 12—Battery

[0034] 121—Battery cell; 13—Processor; 14—Memory

[0035] 1—Electronic devices Detailed Implementation

[0036] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0037] The flowchart shown in the attached diagram is for illustrative purposes only and does not necessarily include all content and operations / steps, nor does it necessarily have to be performed in the described order. For example, some operations / steps can be broken down, combined, or partially merged, and some steps can be deleted. Therefore, the actual execution order may change depending on the actual situation.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0039] It should be noted that the terms "first" and "second" in the specification, claims and drawings of this application are used to distinguish similar objects, rather than to describe a specific order or sequence.

[0040] The State of Charge (SOC) of a battery is a crucial parameter describing its operating state, typically expressed as the ratio of remaining battery capacity to the battery's actual capacity. Users can use the displayed SOC to determine the remaining power of energy storage products or electronic devices. However, existing methods for calculating displayed SOC have inherent errors, especially at the end of the charging and discharging process, where these errors are amplified. This can lead to sudden changes in the displayed SOC or prolonged periods of instability, resulting in low accuracy and significantly degrading the user experience.

[0041] For example, in fast or slow charging mode, the displayed SOC at the charging end remains stuck at 99% for an extended period. Please refer to... Figure 1 , Figure 1 This is a schematic diagram showing the SOC (State of Charge) increasing over time in fast charging mode. Figure 1 It can be seen that in fast charging mode, the SOC increases relatively steadily from 0 to 99%, but the charging end remains at 99% for a long time, for example... Figure 1 The displayed SOC at points a and b is 99%, but there is a pause of approximately 41 minutes between points a and b. The same phenomenon occurs when using slow charging mode, where the displayed SOC remains stuck at 99% for an extended period.

[0042] For example, in low-current mode, the displayed SOC at the end of the charging process shows a sudden change. Please refer to [link / reference needed]. Figure 2 , Figure 2 This is a schematic diagram showing the SOC (State of Charge) increase over time during battery charging in low-current mode (charging current between 1.2A and 3A). From... Figure 2 It can be seen that in low current mode, the displayed SOC increases to 93% (refer to...). Figure 2 After point C), it rapidly increases to 100% within 5 seconds (see point C). Figure 2 (point d).

[0043] Therefore, this application provides a SOC correction method, a battery module, and an electronic device to improve the display accuracy of the battery's displayed SOC. These embodiments will be described in detail below with reference to the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0044] First, please refer to Figure 3 , Figure 3 This is a schematic diagram of one implementation environment involved in this application. This implementation environment uses battery module 10 as an example. Figure 3In this configuration, the battery module 10 includes a Battery Management System (BMS) 11 and a battery 12. The Battery Management System 11 controls the charging and discharging of the battery 12. The battery 12 includes at least one cell 121. Figure 3 In the example shown, the battery management system 11 in the battery module 10 is also used to perform SOC correction on the battery 12 of the battery module 10. That is, the SOC correction method provided in this application is executed by the battery management system 11. Further, it can be executed by a processor (not shown in the figure) loaded with the battery management system 11.

[0045] It is understood that in some embodiments, the battery management system 11 may also be configured outside the battery module 10, for example, loaded on a processor independent of the battery module 10. In this case, the SOC correction method of this application is executed by the processor independent of the battery module 10.

[0046] Please refer to Figure 4 This is a flowchart illustrating a SOC correction method provided in an embodiment of this application. The SOC correction method includes:

[0047] Step S410: In each operating cycle, acquire the battery charging parameters, including the displayed SOC and battery voltage.

[0048] In step S410, the operating cycle can be the controller's operating cycle, during which the controller acquires battery parameters to execute the SOC correction method. That is, the controller periodically executes the SOC correction method and updates the displayed SOC in each operating cycle. This allows for timed refreshing of the battery's displayed SOC, with the refresh frequency depending on the controller's operating cycle. When the operating cycle is extremely short, the displayed SOC is close to the real-time SOC.

[0049] In this embodiment, the displayed SOC can be calculated based on the battery capacity information. Furthermore, the method for calculating the displayed SOC can vary; for example, it can be calculated using the ampere-hour integration method or based on the extended Kalman filter (EKF). This application does not limit the method of calculating the displayed SOC; in other embodiments, other methods can also be used to calculate the displayed SOC. It is understood that the battery management system 11 can directly obtain the currently calculated displayed SOC from memory or registers. However, as... Figure 1 and Figure 2This indicates that existing SOC calculation methods have certain errors, especially at the end of the charge and discharge cycle where the error is amplified, resulting in low accuracy. Therefore, the displayed SOC obtained in step S410 contains some error and may not necessarily represent the actual SOC of the battery.

[0050] In this embodiment, the battery management system 11 can acquire battery parameters through a front-end analog chip to obtain the battery voltage. Understandably, the method for acquiring battery charging parameters can be set according to actual needs, and this application does not limit this.

[0051] Step S420: When the battery charging parameters meet the preset conditions, determine the target SOC of the battery.

[0052] In step S420, the preset condition refers to the condition that triggers the SOC correction method. Thus, when the battery charging parameters meet the preset condition, it indicates that the current displayed SOC has a large error. At this time, the controller triggers the SOC correction method and obtains the target SOC of the battery.

[0053] In step S420, the target SOC is the SOC value that is close to the actual SOC of the battery when the battery charging parameters meet preset conditions. Since the battery parameters include the displayed SOC and the battery voltage, the target SOC can be determined in step S420 when the displayed SOC and the battery voltage meet the preset conditions.

[0054] Specifically, in some embodiments, a lookup table can be established regarding the displayed SOC, battery voltage, and target SOC. Thus, after obtaining the displayed SOC and battery voltage in step S420, a lookup operation can be performed to determine the target SOC. In other embodiments, the battery module 10 may further include a memory that stores functional relationships regarding the displayed SOC, battery voltage, and target SOC. Thus, after obtaining the displayed SOC and battery voltage in step S420, the target SOC can be calculated based on these functional relationships. The lookup table and functional relationships can be obtained based on multiple sets of test data from the battery module in a laboratory setting.

[0055] Understandably, existing SOC correction methods typically trigger SOC correction based on battery voltage. However, taking fast or slow charging modes as an example, there is a constant-voltage charging phase during battery charging. Thus, when the SOC is artificially high (i.e., the displayed SOC is greater than the actual SOC), and the battery is in the constant-voltage charging phase (battery voltage remains constant), even if the battery voltage has not reached the voltage value that triggers SOC correction, issues such as… Figure 1The image shows a battery SOC that remains stagnant at 99% for an extended period. When the battery SOC is artificially low (i.e., the displayed SOC is lower than the actual SOC), the battery voltage may, at the moment it reaches the voltage value that triggers SOC correction, adjust the battery's SOC, causing a sudden surge in SOC, resulting in... Figure 2 The image shows a sudden increase in battery SOC.

[0056] In step S420 of this application, the battery parameters include the displayed SOC and the battery voltage, and SOC correction is triggered only when the displayed SOC and the battery voltage meet preset conditions. Thus, step S420 comprehensively considers both battery voltage and displayed SOC, enabling more accurate SOC correction.

[0057] Step S430: Determine the SOC correction factor based on the target SOC and the displayed SOC.

[0058] In step S430, the correction coefficient is related to both the target SOC and the displayed SOC. The SOC correction coefficient characterizes the difference between the displayed SOC and the target SOC within the operating cycle; that is, it characterizes the difference between the displayed SOC and the actual SOC within the operating cycle. A larger absolute value of the SOC correction coefficient indicates a greater deviation of the current displayed SOC from the actual SOC, resulting in a faster correction rate; conversely, a smaller absolute value indicates a smaller deviation of the current displayed SOC from the actual SOC, resulting in a smaller correction rate.

[0059] Step S440: Update the displayed SOC according to the SOC correction coefficient, and display the updated displayed SOC.

[0060] In step S440, the displayed SOC is adjusted according to the SOC correction factor to narrow the gap between the displayed SOC and the actual SOC, and the updated displayed SOC is displayed. Thus, by adjusting the displayed SOC based on the SOC correction factor determined by the target SOC, the trend of the battery's displayed SOC change can follow the target SOC change, making the battery's displayed SOC change more consistent with the actual SOC change trend.

[0061] It is understood that the SOC correction method provided in this application obtains the battery's charging parameters, and when the battery's charging parameters meet preset conditions, introduces a target SOC that is close to the actual SOC. A SOC correction coefficient is then determined based on the displayed SOC and the target SOC, and the displayed SOC is updated according to the SOC correction coefficient, so that the displayed SOC change trend follows the actual SOC change. Thus, the SOC correction method provided in this application can make the corrected SOC change more consistent with the actual SOC change trend, thereby reducing sudden SOC changes or prolonged periods of inactivity at the end of charging and effectively improving the accuracy of the battery's SOC display.

[0062] Furthermore, the charging parameters include the displayed SOC and battery voltage. Compared to the existing method that only triggers SOC correction based on battery voltage, this method can comprehensively consider the battery voltage and the displayed SOC, thereby achieving more accurate SOC correction.

[0063] It is understood that after executing step S410, if there is an error in the displayed SOC obtained in step S410, the obtained displayed SOC may be either falsely high or falsely low. The following embodiments of this application further illustrate the specific working process of the SOC correction method provided by this application in two scenarios: falsely high displayed SOC triggering correction, or falsely low displayed SOC triggering correction.

[0064] Scenario 1: Displaying an excessively high SOC triggers SOC correction.

[0065] It's understandable that the displayed SOC and battery voltage generally increase with charging time. Multiple sets of tests conducted in the laboratory can obtain test data on the relationship between battery voltage and the corresponding actual SOC during the charging process. Furthermore, these test data can be used to determine the minimum battery voltage corresponding to a specific actual SOC value, or the maximum actual SOC corresponding to a specific battery voltage value. Thus, based on multiple sets of test data, it can be determined whether the obtained displayed SOC is artificially inflated.

[0066] For example, in some embodiments, step S420 may include step S421 as follows:

[0067] Step S421: When the displayed SOC is greater than or equal to the preset SOC and the battery voltage is less than the first voltage threshold, the preset SOC is determined as the target SOC.

[0068] In step S421, the minimum battery voltage corresponding to the preset SOC is set as a first voltage threshold. Specifically, when the displayed SOC is greater than or equal to the preset SOC, and its corresponding battery voltage is greater than the first voltage threshold, it indicates that the obtained displayed SOC is not artificially high. When the displayed SOC is greater than or equal to the preset SOC, and its corresponding battery voltage is less than the first voltage threshold, it indicates that the obtained displayed SOC is artificially high. Thus, by comparing the obtained displayed SOC and battery voltage with the preset SOC and the first voltage threshold respectively, it can be confirmed whether the current displayed SOC is artificially high.

[0069] In step S421, when it is confirmed that the displayed SOC is artificially high, a preset SOC is determined as the target SOC to trigger SOC correction. Clearly, when the acquired displayed SOC is artificially high, the preset SOC is closer to the actual SOC than the acquired displayed SOC. Thus, by using the preset SOC as the target SOC to participate in correcting the displayed SOC, the trend of displayed SOC changes can be corrected.

[0070] Furthermore, considering that the preset SOC and the first voltage threshold may differ depending on the battery's charging mode, in some embodiments, before performing step S421, step S420 of the SOC correction method provided in this application further includes the following steps:

[0071] Step S422: Determine the battery charging mode.

[0072] In some embodiments, the battery parameters further include charging current. In step S422, the current charging mode of the battery can be determined by acquiring the charging current. For example, when the detected charging current is between 1.2A (Amperes) and 3A, the battery is considered to be charging in a first charging mode; when the detected charging current is greater than 3A, the battery is considered to be charging in a second charging mode. The first charging mode can be a low-current mode; the second charging mode can be a fast charging mode or a slow charging mode.

[0073] In some embodiments, the battery voltage or charging power differs for different charging modes. Thus, the battery charging mode can be determined by performing a lookup operation using the obtained battery voltage or charging power. This application does not limit the method for determining the battery charging mode. For example, in other embodiments, the battery management system 11 can also communicate with the power supply device via a charging protocol and determine the corresponding charging mode by reading the charging setting parameters in the charging protocol.

[0074] Step S423: Determine the preset SOC and the first voltage threshold corresponding to the preset SOC according to the charging mode.

[0075] In this embodiment, when the battery is confirmed to be in the first charging mode in step S422, the preset SOC can be 90% and the first voltage threshold can be 4040mV (millivolts); when the battery is confirmed to be in the second charging mode in step S422, the preset SOC can be 87.7% and the first voltage threshold can be 4110mV (millivolts). For example, the first charging mode can be a fast charging mode or a slow charging mode, and the second charging mode can be a low-current charging mode.

[0076] It is understood that in this embodiment, the preset SOC and the first voltage threshold values ​​in step S423 can be obtained from multiple sets of laboratory test data. This application does not limit the values ​​of the preset SOC and the first voltage threshold. In other embodiments, the preset SOC and the first voltage threshold can be adjusted according to different battery specifications, battery charging modes, and corresponding laboratory test data.

[0077] Thus, in some embodiments, by performing the above step S421 (or performing steps S422, S423 and S421), the determination of the target SOC in step S420 can be achieved.

[0078] Please continue reading. Figure 5 In some embodiments, after determining the target SOC, step S430 includes the following steps:

[0079] Step S510: Calculate the difference between the target SOC and the displayed SOC to obtain the first SOC difference.

[0080] For example, if the target SOC is e and the displayed SOC is f, then the first SOC difference is ef.

[0081] Step S520: Calculate the difference between the SOC when the battery is fully charged and the target SOC to obtain the second SOC difference.

[0082] Understandably, the SOC when the battery is fully charged is 100%. Thus, the second SOC difference is 100% - e.

[0083] Step S530: Determine the adjustment step size based on the first SOC difference and the second SOC difference; wherein the adjustment step size is positively correlated with the first SOC difference and negatively correlated with the second SOC difference.

[0084] For example, in some embodiments, the formula for calculating the adjustment step size may be:

[0085] g=k*(ef) / (100%-e) (1)

[0086] In formula (1), g is the adjustment step size and k is the adjustment coefficient. The adjustment coefficient is used to limit the adjustment step size to keep its value within a suitable range. Understandably, in other embodiments, the adjustment step size can be calculated using other formulas, as long as the adjustment step size and the difference between the first SOC are positively correlated and the difference between the adjustment step size and the second SOC are negatively correlated. This application does not impose any restrictions on this.

[0087] Step S540: Calculate the sum of the initial correction coefficient and the adjustment step size to obtain the SOC correction coefficient.

[0088] In this embodiment, the initial correction factor is 1. Therefore, the formula for calculating the SOC correction factor is:

[0089] m = 1 + g; that is,

[0090] m=1+k*(ef) / (100%-e) (2)

[0091] In formula (2), m is the SOC correction coefficient.

[0092] Please continue reading. Figure 6 After obtaining the SOC correction coefficient, step S440 includes the following steps:

[0093] Step S610: Calculate the change in SOC of the battery during the operating cycle.

[0094] In step S610, the SOC change refers to the change in battery SOC during the current operating cycle. For example, in some embodiments, when the displayed SOC is calculated using the ampere-hour integration method, the SOC change can be the integral value of SOC obtained by integrating the battery capacity, battery current, and charge / discharge efficiency during the operating cycle.

[0095] Step S620: Determine the target SOC change based on the SOC correction coefficient and the SOC change.

[0096] In some embodiments, the formula for calculating the target SOC change is:

[0097] ΔSOC=j*m*n+d (3)

[0098] In formula (3), ΔSOC represents the target SOC change; j is the first adjustment parameter; n is the SOC change; and d is the second adjustment parameter. It can be understood that the first adjustment parameter j and the second adjustment parameter d are used to jointly adjust the target SOC change to limit its amplitude. Here, j is a percentage less than or equal to 1; d is a constant, and d can be positive or negative.

[0099] In this embodiment, the first adjustment parameter j is 1, and the second adjustment parameter d is 0. That is, in this embodiment, the target SOC change is the product of the SOC correction coefficient m and the SOC change n. It can be understood that in other embodiments, the values ​​of the first adjustment parameter j and the second adjustment parameter d can be adjusted according to the debugging situation to obtain the target SOC change.

[0100] Step S630: Update the displayed SOC based on the target SOC change.

[0101] In this embodiment of the application, the updated display SOC is the sum of the changes in the obtained display SOC and the target SOC.

[0102] Understandably, since the adjustment step size *m* is positively correlated with the first SOC difference and negatively correlated with the second SOC difference, the larger the difference between the target SOC and the acquired display SOC (i.e., the larger the value of *ef*), the larger the absolute value of the adjustment step size, and the faster the correction rate. Conversely, when the target SOC is closer to the SOC at which the battery is fully charged (i.e., the smaller the value of 100% - *e*), the larger the absolute value of the adjustment step size, the faster the correction rate. Thus, the adjustment step size in this embodiment is a dynamic value based on the changes in the display SOC and the target SOC, enabling dynamic correction of the display SOC with higher adjustment accuracy.

[0103] Understandably, when the displayed SOC is artificially high, the first SOC difference is negative. Therefore, the adjustment step size calculated according to the formula is negative, and the SOC correction coefficient is less than 1. Thus, the target SOC change remains positive, but is less than the actual SOC change, causing the displayed SOC updated based on the target SOC change to grow at a slower pace, making the updated displayed SOC more consistent with the actual SOC growth trend of the battery.

[0104] Understandably, when the adjustment step size is too large, it can easily cause a jump in the corrected displayed SOC; when the adjustment step size is too small, the change in the target SOC is too small to quickly keep up with the change in the battery's actual SOC. Therefore, this embodiment of the application sets an adjustment coefficient k to keep the adjustment step size within a reasonable range, thereby enabling the calculated change in the target SOC to better correct the gap between the displayed SOC and the actual SOC, so that the updated displayed SOC approaches the battery's actual SOC.

[0105] Understandably, this application does not impose specific limitations on the value of the adjustment coefficient k, and the adjustment coefficient k can be adjusted accordingly based on the debugging situation.

[0106] Understandably, when the SOC correction method is executed again in the next operating cycle, the displayed SOC obtained in step S410 is the updated displayed SOC. In this way, after SOC correction in multiple operating cycles, the development trend of the battery's displayed SOC can be made closer to the development trend of the battery's actual SOC, reducing the occurrence of sudden changes or long-term stagnation in the displayed SOC, and effectively improving the SOC display accuracy of the battery.

[0107] In some embodiments, after updating the obtained display SOC, the SOC correction method provided in this application further includes the following steps:

[0108] When the battery voltage is lower than the second voltage threshold, the displayed SOC is limited to not exceed the preset SOC threshold; or

[0109] When the battery voltage is greater than or equal to the second voltage threshold, the displayed SOC will be updated to the SOC when the battery is fully charged.

[0110] It can be understood that the second voltage threshold is the battery voltage when the battery is fully charged, and overvoltage protection will be triggered when the battery voltage reaches the second voltage threshold. That is, when the battery voltage is greater than or equal to the second voltage threshold, it indicates that the battery is fully charged; when the battery voltage is less than the second voltage threshold, it indicates that the battery is not fully charged. Furthermore, since the preset SOC threshold is less than the SOC when the battery is fully charged (100%), when the battery voltage is less than the second voltage threshold, the updated displayed SOC is limited to be less than or equal to the preset SOC threshold, ensuring that the updated displayed SOC is less than 100%, thus preventing the updated displayed SOC from incorrectly indicating that the battery is fully charged. When the battery voltage is greater than or equal to the second voltage threshold, the displayed SOC is updated to 100%, allowing for timely correction of the displayed SOC. In some embodiments, the preset SOC threshold is 99%.

[0111] Please see Figure 7a , Figure 7b and Figure 7c , Figures 7a-7c These are schematic diagrams showing the SOC curves before and after the SOC correction method for the first scenario of battery application in fast charging mode, slow charging mode, and low current mode. Figure 7a Curve S1 represents the original SOC curve of the battery during fast charging mode. Figure 7a Curve S2 is the SOC curve after the displayed SOC is corrected according to the SOC correction method provided in the above embodiment when the battery is charging in fast charging mode. Figure 7b Curve S3 is the SOC curve in relevant technologies when the battery is charging in slow charging mode. Figure 7b Curve S4 is the SOC curve after the displayed SOC is corrected according to the SOC correction method provided in the above embodiment when the battery is charging in slow charging mode. Figure 7c Curve S5 is the original SOC curve of the battery when it is charging in low current mode. Figure 7c Curve S6 represents the SOC curve after correcting the displayed SOC according to the SOC correction method provided in the above embodiment during battery charging in low-current mode. Clearly, according to... Figures 7a-7c It can be seen that by applying the SOC correction method provided in this application, the SOC sudden change phenomenon at the end of charging can be reduced in various charging modes, and the time length for which the SOC remains unchanged can be reduced, making the SOC change more consistent with the actual SOC change trend, and effectively improving the SOC display accuracy of the battery.

[0112] The second scenario: Low SOC triggers SOC correction.

[0113] In the second scenario, after obtaining the displayed SOC and battery voltage through step S410, step S420 includes:

[0114] Step S424: When the battery voltage is greater than or equal to the first voltage threshold, determine the target SOC of the battery based on the battery voltage and the battery charging mode.

[0115] Similarly, based on multiple sets of tests conducted in the laboratory comparing battery voltage with the actual SOC of the battery, it was confirmed that when the battery voltage is greater than or equal to a first voltage threshold, the displayed SOC of the battery is usually falsely low. Therefore, in step S424, when the battery voltage is greater than or equal to the first voltage threshold, it is determined that the displayed SOC of the battery is falsely low. In other words, when the displayed SOC is falsely low, SOC correction is triggered by the battery voltage.

[0116] It is understood that the target SOC is related to the battery's charging mode and battery voltage. In some embodiments, based on multiple sets of test data on the relationship between battery voltage and target SOC obtained in the laboratory, a mapping relationship between battery voltage and target SOC can be established under different charging modes, and a lookup table or calculation function can be generated. Thus, in step S424, when the battery voltage corresponding to a certain charging mode is obtained, the processor in the battery management system 11 can perform a lookup operation or calculation to confirm the corresponding target SOC, thereby correcting the displayed SOC.

[0117] Furthermore, this application also provides some embodiments for determining the target SOC of a battery based on the battery voltage and the battery charging mode. For example, in some embodiments, step S424 may include:

[0118] Step S425: When the charging mode is the first charging mode, obtain the battery charging current; determine the target SOC based on the charging current and battery voltage.

[0119] The first charging mode can be either fast charging or slow charging. The battery charging current can be obtained by the battery management system 11 through the front-end analog chip. The following content uses fast charging as an example to illustrate the process by which the battery determines the target SOC based on the charging current and battery voltage.

[0120] First, select the first voltage V1 and the second voltage V2 (refer to...) Figure 8aThe system establishes a first equation regarding the virtual correction voltage based on a first voltage V1 and a second voltage V2. In some embodiments, the first voltage V1 is a first voltage threshold. This first voltage threshold can be the voltage value corresponding to a battery's actual SOC of 90%, for example, 4110 mV (millivolts). The second voltage V2 is the battery voltage value when the battery enters the constant-voltage charging stage during charging, for example, 4175 mV. In some embodiments, the second voltage V2 can also be the difference between the battery voltage value in the constant-voltage charging stage and a preset voltage value. Thus, by subtracting the preset voltage value, the occurrence of extreme situations can be reduced, improving the charging safety of the battery.

[0121] Then, based on the first voltage V1 and the second voltage V2, a first virtual voltage coordinate (V1,4) and a second virtual voltage coordinate (V2,0) are constructed. Finally, based on the first virtual voltage coordinate (V1,4) and the second virtual voltage coordinate (V2,0), the first equation regarding the virtual corrected voltage is obtained:

[0122] Yvolt = -X1 / 15 + 278

[0123] Where Yvolt is the virtual correction voltage, and X1 is the battery voltage value used to determine the target SOC.

[0124] Next, select the first current I1 and the second current I2 (refer to...) Figure 8b A second equation regarding the virtual corrected current is established based on the first current I1 and the second current I2. In some embodiments, the first current I1 is the charging current during the last constant current charging stage in the battery charging process, for example, 16000mA. The second current I2 is the sum of the charging cutoff current (e.g., 3000mA) and the initial current (e.g., 1A), thus the second current I2 can be 4000mA. It can be understood that by adding the initial current to the cutoff current, the occurrence of extreme situations can be reduced, and the charging safety of the battery can be improved.

[0125] Then, based on the first current I1 and the second current I2, a first virtual current coordinate (I1, 5) and a second virtual current coordinate (I2, 9) are constructed. Finally, based on the first virtual current coordinate (I1, 5) and the second virtual current coordinate (I2, 9), the second equation regarding the virtual corrected current is obtained:

[0126] Ycur=-X2 / 3000+31 / 3

[0127] Where Ycur is the virtual correction current and X2 is the charging current value used to determine the target SOC.

[0128] Please refer to the following: Figure 8a and Figure 8b . Figure 8a and Figure 8b The figures show the voltage and current change curves of the same battery in fast charging mode. Figure 8a and Figure 8b As can be seen, towards the end of the battery charging process, the charging current decreases as the battery voltage increases. Since both battery voltage and charging current affect the battery SOC in commonly used SOC calculation methods (such as the ampere-hour integration method), virtual correction points (e.g., 4, 0, 5, 9, etc.) are introduced into the first virtual voltage coordinate, second virtual voltage coordinate, first virtual current coordinate, and second virtual current coordinate to calculate the target SOC. Specifically, 4 and 0 in the first and second virtual voltage coordinates are the boundary values ​​for the virtual correction points of voltage; that is, during the voltage increase at the end of the charging process, the corresponding virtual correction points can be 4, 3, 2, 1, and 0 respectively. Similarly, 5 and 9 in the first and second virtual current coordinates are the boundary values ​​for the virtual correction points of current; that is, during the current decrease at the end of the charging process, the corresponding virtual correction points can be 5, 6, 7, 8, and 9 respectively. Understandably, these virtual correction points have no specific physical meaning; they are merely intermediate values ​​used to calculate the mapping relationship between the target SOC and the battery voltage and charging current.

[0129] Furthermore, the virtual correction point, virtual correction voltage, and virtual correction current satisfy a third-party program:

[0130] Ysoc=Ycur–Yvolt,Ysoc∈[1,9]

[0131] Finally, Figure 8a and Figure 8b The voltage and current values ​​of the battery at the same time point are obtained and substituted into the first equation in the third-party program. The actual SOC of the battery at that time point is then obtained. This yields a mapping table between the virtual correction point and the actual SOC of the battery. For example, please refer to the table below:

[0132] Mapping table between virtual correction point Ysoc and battery SOC

[0133]

[0134] Furthermore, the Ysoc in the table above is fitted to the target SOC to generate the corresponding fourth equation, for example:

[0135] Tsoc=h*Ysoc 2 +i*Ysoc+p

[0136] Where h = -0.02435, i = 1.662, p = 86.06, and Tsoc represents the target SOC, with Tsoc ∈ [87.7, 99]. Thus, a mapping relationship between the target SOC and the charging current and battery voltage can be established through the virtual correction point Ysoc. That is, in step S425, based on the battery voltage, charging current, the first equation, the second equation, and the third-party program, the virtual correction point corresponding to the battery voltage and charging current can be calculated first; then, based on the calculated virtual correction point and the fourth equation, the target SOC corresponding to the current battery voltage and charging current can be obtained.

[0137] In other embodiments, step S424 may include:

[0138] Step S426: When the charging mode is the second charging mode, determine the target SOC based on the battery voltage and the preset mapping relationship.

[0139] The second charging mode can be a low-current charging mode. The charging current in the first charging mode is greater than the charging current in the second charging mode. For example, in some embodiments, the charging current in the first charging mode is greater than 3A (amperes), and the charging current in the second charging mode is greater than or equal to 1.2A and less than or equal to 3A.

[0140] Please refer to Figure 9 , Figure 9 This is a curve showing the battery voltage change over charging time in low-current mode. Furthermore, in low-current mode, there is no switching between constant-current and constant-voltage phases during battery charging; that is, there is no current reduction process during charging. Therefore, the two voltages and their corresponding SOC values ​​can be directly obtained from the voltage change curve in low-current mode, thus establishing a mapping relationship between battery voltage and the target SOC.

[0141] For example, select Figure 9 The third voltage V3 and the fourth voltage V4 are given. The third voltage V3 is the voltage value corresponding to a battery SOC of 90%, for example, 4040mV; the fourth voltage V4 is the voltage value corresponding to a battery SOC of 100%, for example, 4140mV. Thus, the fifth equation representing the mapping relationship between battery voltage and target SOC in low-current mode can be obtained:

[0142] Tsoc = X3 / 10 – 314

[0143] Where X3 is the battery voltage value under low current mode, and Tsoc represents the target SOC.

[0144] Thus, in step S426, the target SOC corresponding to the battery voltage can be determined based on the battery voltage and the fifth equation mentioned above.

[0145] It is understandable that in the second scenario, steps S510-S540 and S610-S630 described in the first scenario can continue to be executed to update the displayed SOC. That is to say, in the second scenario, simply replacing step S240 of obtaining the target SOC in the first scenario with step S420 in the second scenario will achieve the update of the displayed SOC in the second scenario.

[0146] Please continue reading. Figure 10a , Figure 10b and Figure 10c . Figure 10a , Figure 10b and Figure 10c These are schematic diagrams showing the SOC curves before and after the SOC correction method in the second scenario of battery application, under fast charging mode, slow charging mode, and low current mode. Figure 10a Curve S7 is the displayed SOC curve in the relevant scheme when the battery is charging in fast charging mode. Figure 10a Curve S8 is the display SOC curve after the display SOC is corrected according to the SOC correction method provided in the above embodiment when the battery is charging in fast charging mode. Figure 10b Curve S9 is the displayed SOC curve in the relevant scheme when the battery is charging in slow charging mode. Figure 10b Curve S10 is the display SOC curve after the display SOC is corrected according to the SOC correction method provided in the above embodiment when the battery is charging in slow charging mode. Figure 10c Curve S11 is the displayed SOC curve in the relevant scheme when the battery is charging in low current mode. Figure 10c Curve S12 represents the display SOC curve after correcting the display SOC according to the SOC correction method provided in the above embodiment during battery charging in low-current mode. Clearly, according to... Figures 10a-10b It can be seen that in one scenario, the displayed SOC curve in the relevant scheme is artificially low at the beginning of charging. Therefore, the displayed SOC increases rapidly in the later stages of charging to compensate for the previous slow growth. However, this results in the displayed SOC in the relevant scheme increasing to an artificially high level, and then stagnating for a long time at the end of charging. According to Figure 10c It can be seen that in another scenario, if the displayed SOC in the relevant solution remains artificially low, when the battery voltage increases to a value that triggers SOC correction during charging, the displayed SOC is corrected, causing a sudden surge in displayed SOC. Clearly, existing solutions cannot resolve the abnormal increase in displayed SOC in either of these scenarios. However, according to... Figures 10a-10cAs can be seen, by applying the SOC correction method provided in this application, the displayed SOC follows the actual SOC change more gradually, and the gap between it and the actual SOC gradually narrows. This reduces the SOC sudden change phenomenon at the end of charging in various charging modes and reduces the length of time that the SOC remains unchanged, making the SOC change more consistent with the actual SOC change trend and effectively improving the SOC display accuracy of the battery.

[0147] It is understood that the embodiments of this application only illustrate the working principle and process of the SOC correction method provided in this application using fast charging mode, slow charging mode, and low current mode as examples. This application does not limit the charging mode mentioned in the SOC correction method. In other embodiments, the values ​​of parameters such as the first voltage threshold and preset SOC can also be adjusted according to the corresponding charging mode to realize the SOC correction method provided in this application.

[0148] Please see Figure 11 This application also provides a battery module 10 in one embodiment. The battery module 10 includes a battery 12, a processor 13, and a memory 14. The processor 13 is connected to the battery 12 and the memory 14. The memory 14 includes one or more computer instructions. The one or more computer instructions are executed by the processor 13 to implement the SOC correction method described in any of the above embodiments. It is understood that in some embodiments, at least one of the processor 13 and the memory 14 may be integrated into the battery management system 11. In other embodiments, the processor 13 may also be a standalone controller. The battery 12 includes, but is not limited to, rechargeable batteries such as nickel-cadmium batteries, nickel-metal hydride batteries, lithium-ion batteries, and secondary alkaline zinc-manganese batteries; this application does not limit the type of battery 12.

[0149] Please continue reading. Figure 12 An embodiment of this application also provides an electronic device 1. The electronic device 1 includes a battery module 10 as described above. The electronic device 1 includes at least two battery modules 10 as described above.

[0150] It is understood that electronic device 1 can be an independent power supply device, and electronic device 1 can also integrate a power conversion device. In this way, electronic device 1 can form a microgrid system with an external power supply, such as an AC power supply or a DC power supply. For example, electronic device 1 can be a large household battery, a portable outdoor power supply, etc. In some other embodiments, electronic device 1 can be a device with an integrated battery module, including but not limited to robots, robot vacuum cleaners, lawnmowers, laptops, and other devices that need to display the battery SOC.

[0151] This application also provides a computer-readable medium storing a computer program thereon, which, when executed by a processor, implements the SOC correction method as described in the above technical solutions. The computer-readable medium may be a portable compact disc read-only memory (CD-ROM) and include program code, and may run on a terminal device, such as a personal computer. However, the program product of this invention is not limited thereto. In this document, the readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, apparatus, or device.

[0152] The above-described program product may employ any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: electrical connections having one or more wires, portable disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0153] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, carrying readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A readable signal medium may also be any readable medium other than a readable storage medium, capable of sending, propagating, or transmitting programs for use by or in conjunction with an instruction execution system, apparatus, or device.

[0154] The program code contained on the readable medium may be transmitted using any suitable medium, including but not limited to wireless, wired, optical fiber, RF, etc., or any suitable combination thereof.

[0155] Program code for performing the operations of this invention can be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java and C++, and conventional procedural programming languages ​​such as C or similar languages. The program code can execute entirely on the user's computing device, partially on the user's device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server. In cases involving remote computing devices, the remote computing device can be connected to the user's computing device via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0156] Furthermore, the above figures are merely illustrative of the processes included in the method according to exemplary embodiments of the present invention, and are not intended to be limiting. It is readily understood that the processes shown in the above figures do not indicate or limit the temporal order of these processes. Additionally, it is readily understood that these processes may be executed synchronously or asynchronously, for example, in multiple modules.

[0157] Furthermore, those skilled in the art should recognize that the above embodiments are merely illustrative of this application and are not intended to limit this application. Any appropriate changes and variations made to the above embodiments within the essential spirit and scope of this application fall within the scope of this application's disclosure.

Claims

1. A SOC correction method, characterized in that, The SOC correction method includes: In each operating cycle, the battery charging parameters are acquired, including the displayed SOC and battery voltage; The charging mode of the battery is determined. When the charging parameters of the battery meet the preset conditions corresponding to the charging mode, the target SOC of the battery corresponding to the charging mode is determined. Determine the SOC correction coefficient based on the target SOC and the displayed SOC; The display SOC is updated according to the SOC correction coefficient, and the updated display SOC is displayed. When the charging parameters of the battery meet the preset conditions corresponding to the charging mode, determining the target SOC of the battery corresponding to the charging mode includes: When the displayed SOC is greater than or equal to the preset SOC and the battery voltage is less than the first voltage threshold, the preset SOC is determined to be the target SOC, wherein the preset SOC and the first voltage threshold are determined according to the charging mode; When the battery voltage is greater than or equal to a first voltage threshold, the target SOC of the battery is determined according to the battery voltage and the charging mode of the battery, wherein the first voltage threshold is determined according to the charging mode; Wherein, determining the target SOC of the battery based on the battery voltage and the battery charging mode includes: When the charging mode is the first charging mode, the charging current of the battery is acquired; the target SOC is determined based on the charging current and the battery voltage; or When the charging mode is the second charging mode, the target SOC is determined according to the battery voltage and a preset mapping relationship; the charging current in the first charging mode is greater than the charging current in the second charging mode.

2. The SOC correction method as described in claim 1, characterized in that, The step of determining the SOC correction coefficient based on the target SOC and the displayed SOC includes: Calculate the difference between the target SOC and the displayed SOC to obtain the first SOC difference; Calculate the difference between the SOC when the battery is fully charged and the target SOC to obtain the second SOC difference; The adjustment step size is determined based on the first SOC difference and the second SOC difference; wherein the adjustment step size is positively correlated with the first SOC difference and negatively correlated with the second SOC difference. The SOC correction coefficient is obtained by calculating the sum of the initial correction coefficient and the adjustment step size.

3. The SOC correction method as described in claim 1, characterized in that, The step of updating the display SOC according to the SOC correction coefficient includes: Calculate the change in SOC of the battery during the operating cycle; The target SOC change is determined based on the SOC correction coefficient and the SOC change. The displayed SOC is updated based on the change in the target SOC.

4. The SOC correction method according to any one of claims 1-3, characterized in that, The method further includes: When the battery voltage is less than a second voltage threshold, the displayed SOC is limited to not exceed a preset SOC threshold; or When the battery voltage is greater than or equal to the second voltage threshold, the displayed SOC is updated to the SOC when the battery is fully charged; wherein the preset SOC threshold is less than the SOC when the battery is fully charged.

5. A battery module, characterized in that, The battery module includes a battery, a processor, and a memory. The memory includes one or more computer instructions, which are executed by the processor to implement the SOC correction method as described in any one of claims 1-4.

6. An electronic device, characterized in that, The electronic device includes the battery module as described in claim 5.

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