Battery SOC correction method and vehicle

Abstract

The present disclosure relates to a battery SOC correction method and a vehicle. The method comprises: determining the SOC of the battery according to the temperature of the battery; determining a correction speed according to the difference between the determined SOC of the battery and the currently output SOC of the battery; and correcting the currently output SOC of the battery according to the determined correction speed. In this way, the influence of the battery temperature on the battery SOC is taken into account, and the correction speed is determined according to the difference between the determined SOC of the battery and the currently output SOC of the battery, so that an appropriate correction speed matching the difference can be determined, and the corrected SOC is made more accurate and reliable, thereby improving the user experience.

Description

Technical Field

[0001] The present disclosure relates to the field of vehicles, and in particular, to a battery SOC correction method and a vehicle. Background Art

[0002] Batteries are the power source of new energy vehicles. The battery state of charge (SOC) is the ratio of the current remaining capacity of the battery to the rated capacity when fully charged. It is one of the important parameters of the battery. During the use of the battery, the estimated result of the battery SOC is inaccurate due to factors such as temperature and battery aging, and the battery SOC needs to be corrected. Summary of the invention

[0003] The purpose of the present disclosure is to provide a battery SOC correction method and a vehicle, which can accurately and reliably correct the SOC of the battery currently output.

[0004] In order to achieve the above object, the present disclosure provides a battery SOC correction method, the method comprising:

[0005] Determine the SOC of the battery based on the temperature of the battery;

[0006] Determining a correction speed according to a difference between the determined SOC of the battery and the SOC of the battery currently output;

[0007] The SOC of the battery currently being output is corrected according to the determined correction speed.

[0008] Optionally, determining the correction speed according to the difference between the determined SOC of the battery and the currently output SOC of the battery includes:

[0009] In a predetermined first corresponding relationship, a correction speed corresponding to a difference between the determined SOC of the battery and the output SOC of the battery is found as the determined correction speed.

[0010] Optionally, in the predetermined first corresponding relationship, the greater the difference between the determined SOC of the battery and the output SOC of the battery, the greater the corresponding correction speed.

[0011] Optionally, the method further comprises:

[0012] When the vehicle is powered on, if the SOC of the battery currently output is greater than a predetermined SOC threshold, it is determined whether the high-segment SOC correction condition is met according to the cell voltage of the battery;

[0013] If the SOC of the battery currently output is less than the SOC threshold, determining whether the low-segment SOC correction condition is met according to the cell voltage of the battery;

[0014] The determining the SOC of the battery according to the temperature of the battery includes:

[0015] If it is determined that the high-range SOC correction condition or the low-range SOC correction condition is satisfied, the SOC of the battery is determined based on the temperature of the battery.

[0016] Optionally, if it is determined that the high-range SOC correction condition or the low-range SOC correction condition is satisfied, determining the SOC of the battery according to the temperature of the battery includes:

[0017] If it is determined that the high-segment SOC correction condition or the low-segment SOC correction condition is satisfied, determining the SOC-open circuit voltage (OCV) curve of the battery according to the temperature of the battery;

[0018] The SOC of the battery corresponding to the current OCV of the battery is determined according to the SOC-OCV curve of the battery as the SOC of the battery.

[0019] Optionally, determining the SOC-open circuit voltage (OCV) curve of the battery according to the temperature of the battery includes:

[0020] A SOC-OCV curve corresponding to the temperature of the battery is searched out in a predetermined second correspondence relationship as the SOC-OCV curve of the battery, wherein the second correspondence relationship includes a correspondence relationship between the temperature of the battery and the SOC-OCV curve of the battery.

[0021] Optionally, if the SOC of the battery currently output is greater than a predetermined SOC threshold, judging whether a high-segment SOC correction condition is met according to the cell voltage of the battery includes:

[0022] When the vehicle is powered on, determining a dormancy time threshold of the vehicle according to the temperature of the battery;

[0023] If the timing time from the last time the vehicle was powered off is greater than the determined sleep time threshold, and the currently outputted SOC of the battery is greater than the SOC threshold, it is determined whether the high-segment SOC correction condition is met based on the battery cell voltage.

[0024] Optionally, if the timing duration from the last time the vehicle was powered off is greater than the determined sleep duration threshold, and the SOC of the battery currently output is greater than the SOC threshold, determining whether the high-segment SOC correction condition is met according to the cell voltage of the battery includes:

[0025] If the timing time starting from the last time the vehicle was powered off is greater than the determined sleep time threshold, the bus current of the vehicle is not greater than the predetermined static current threshold, and the SOC of the battery currently output is greater than the SOC threshold, then it is determined whether the high-segment SOC correction condition is met based on the battery cell voltage.

[0026] Optionally, judging whether a high-segment SOC correction condition is met according to the cell voltage of the battery comprises: if the cell voltage of the battery is greater than a predetermined first voltage threshold, judging that the high-segment SOC correction condition is met;

[0027] The determining whether the low-segment SOC correction condition is met based on the battery cell voltage includes: if the battery cell voltage is greater than a predetermined second voltage threshold, determining that the low-segment SOC correction condition is met, and the first voltage threshold is greater than the second voltage threshold.

[0028] Optionally, determining the correction speed according to the difference between the determined SOC of the battery and the currently output SOC of the battery includes:

[0029] In a predetermined third corresponding relationship, a correction coefficient corresponding to a difference between the determined SOC of the battery and the currently output SOC of the battery is found;

[0030] The correction speed is determined according to the following formula:

[0031] V=(S k+1 -S k ) / Δt=K*I / Q

[0032] Wherein, V is the correction speed, K is the correction coefficient, I is the bus current of the vehicle, Q is the rated capacity of the battery, S k+1 is the SOC of the (k+1)th correction cycle, S k is the SOC of the kth correction cycle, and Δt is the duration of the correction cycle.

[0033] The present disclosure also provides a vehicle, comprising:

[0034] a memory having a computer program stored thereon;

[0035] The processor is used to execute the computer program in the memory to implement the steps of the above-mentioned battery SOC correction method.

[0036] Through the above technical solution, the SOC of the battery is determined according to the temperature of the battery, the correction speed is determined according to the difference between the determined SOC of the battery and the SOC of the battery currently output, and the SOC of the battery currently output is corrected according to the determined correction speed. In this way, the influence of the battery temperature on the battery SOC is taken into account, and the correction speed is determined according to the difference between the determined SOC of the battery and the SOC of the battery currently output, so that an appropriate correction speed matching the difference can be determined, and the corrected SOC is made more accurate and reliable, thereby improving the user experience.

[0037] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0039] Figure 1 is a flow chart of a battery SOC correction method provided by an exemplary embodiment.

[0040] Figure 2 is a flow chart of a battery SOC correction method provided by yet another exemplary embodiment.

[0041] Figure 3 is a block diagram of a battery SOC correction device provided by an exemplary embodiment. DETAILED DESCRIPTION

[0042] The specific implementation of the present disclosure is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0043] It should be noted that all actions of acquiring signals, information or data in the present disclosure are carried out in compliance with the relevant data protection laws and policies of the country where the device is located and with the authorization given by the owner of the corresponding device.

[0044] Figure 1 FIG. 1 is a flow chart of a battery SOC correction method provided by an exemplary embodiment. Figure 1 As shown, the method includes the following steps.

[0045] In step S101 , the SOC of the battery is determined according to the temperature of the battery.

[0046] Battery SOC is the ratio of the current remaining capacity of the battery to the rated capacity when fully charged. For example, when the battery SOC is 100%, the battery is fully charged; when the battery SOC is 0%, the battery is discharged. The temperature of the battery can be obtained based on the collected temperature of the battery module. The temperature of the battery module can be collected using a temperature sensor. The average value of the temperatures of multiple battery modules can be determined as the battery temperature, and the maximum value of the temperatures of multiple battery modules can be determined as the battery temperature.

[0047] When the battery is not in a charging or discharging state, the battery's SOC will also change with the change of temperature. For example, when the battery temperature is 30°C, the battery's SOC is 30%, and when the battery temperature increases to 35°C, the battery's SOC increases to 31%; for another example, when the temperature is 40°C, the battery's SOC is 40%, and when the battery temperature drops to 20°C, the battery's SOC is 37%. Therefore, different battery temperatures can correspond to different SOCs.

[0048] In step S102 , a correction speed is determined according to a difference between the determined battery SOC and the currently outputted battery SOC.

[0049] When the vehicle is powered on, the vehicle control unit (VCU) can calculate the battery SOC by methods in related technologies and output it. For example, the battery SOC can be displayed on an instrument screen inside the vehicle.

[0050] When the difference between the currently determined battery SOC and the currently outputted battery SOC is large, the currently outputted battery SOC can be corrected quickly, and when the difference between the currently determined battery SOC and the currently outputted battery SOC is small, the currently outputted battery SOC can be corrected at a slower rate. After the difference is determined in real time, the corresponding correction speed can be determined according to the difference.

[0051] In step S103, the SOC of the battery currently output is corrected according to the determined correction speed.

[0052] After the correction speed is determined, the SOC of the battery currently outputted may be corrected according to the determined correction speed.

[0053] This method can be applied to lithium iron phosphate batteries. The number of software runs can be preset, for example, 3 times. One second after the vehicle is powered on, it can be determined within the preset number of software runs whether the output battery SOC needs to be corrected.

[0054] Through the above technical solution, the SOC of the battery is determined according to the temperature of the battery, the correction speed is determined according to the difference between the determined SOC of the battery and the SOC of the battery currently output, and the SOC of the battery currently output is corrected according to the determined correction speed. In this way, the influence of the battery temperature on the battery SOC is taken into account, and the correction speed is determined according to the difference between the determined SOC of the battery and the SOC of the battery currently output, so that an appropriate correction speed matching the difference can be determined, and the corrected SOC is made more accurate and reliable, thereby improving the user experience.

[0055] In yet another embodiment, the method of determining the correction speed according to the difference between the determined battery SOC and the currently outputted battery SOC includes:

[0056] In the predetermined first corresponding relationship, a correction speed corresponding to the difference between the determined battery SOC and the output battery SOC is found as the determined correction speed.

[0057] The first corresponding relationship can be preset by the designer. For example, when the difference is 10%, the correction speed is determined to be 3% / s; when the difference is 5%, the correction speed is determined to be 2% / s; when the difference is 2%, the correction speed is determined to be 1% / s.

[0058] In this embodiment, a table lookup method is adopted to quickly determine the correction speed corresponding to the difference between the determined battery SOC and the output battery SOC. The method is simple and the data processing speed is fast.

[0059] In yet another embodiment, in the above-mentioned predetermined first corresponding relationship, the greater the difference between the determined battery SOC and the output battery SOC, the greater the corresponding correction speed.

[0060] The larger the difference between the determined battery SOC and the output battery SOC, the larger the error of the output battery SOC can be considered, and the faster the correction speed required to correct the output SOC is; the smaller the difference between the determined battery SOC and the output battery SOC is, the smaller the error of the output battery SOC is considered, and the slower the correction speed required to correct the output SOC is.

[0061] In yet another embodiment, the above method further includes:

[0062] When the vehicle is powered on, if the SOC of the battery currently output is greater than the predetermined SOC threshold, it is determined whether the high-segment SOC correction condition is met based on the battery cell voltage;

[0063] If the currently outputted battery SOC is less than the SOC threshold, it is determined whether the low-segment SOC correction condition is met based on the battery cell voltage.

[0064] In this embodiment, determining the SOC of the battery according to the temperature of the battery includes:

[0065] If it is determined that the high-range SOC correction condition or the low-range SOC correction condition is satisfied, the SOC of the battery is determined based on the temperature of the battery.

[0066] The SOC threshold can be preset by the designer, for example, it can be 50%. When the SOC of the battery currently output is greater than the predetermined SOC threshold, the SOC of the battery can be considered to be in the high-segment SOC, and when the SOC of the battery currently output is less than the predetermined SOC threshold, the SOC of the battery can be considered to be in the low-segment SOC. It can be determined whether the high-segment SOC correction condition or the low-segment SOC correction condition is met based on the battery cell voltage. The battery has multiple cells, and the voltage of each cell can be obtained. For example, the average value of the multiple cell voltages can be determined as the cell voltage of the battery, and the maximum value of the multiple cell voltages can also be determined as the cell voltage of the battery.

[0067] For example, the necessity of making a correction in the high-range SOC can be judged based on the battery cell voltage, and the conditions that need to be met to make a correction at this time can be set in advance as the high-range SOC correction conditions. The necessity of making a correction in the low-range SOC can also be judged based on the battery cell voltage, and the conditions that need to be met to make a correction at this time can be set in advance as the low-range SOC correction conditions.

[0068] When it is determined that the high-range SOC correction condition or the low-range SOC correction condition is satisfied, the VCU may correct the currently outputted battery SOC according to the battery temperature.

[0069] In this embodiment, different SOC correction conditions are used in the low-segment SOC and high-segment SOC to determine whether to make a correction. In this way, the correction of the low-segment SOC is more consistent with the battery state of the low-segment SOC, and the correction of the high-segment SOC is more consistent with the battery state of the high-segment SOC, thereby being able to accurately and reliably make corrections when the battery is in the low-segment SOC or high-segment SOC.

[0070] In another embodiment, if it is determined that the high-range SOC correction condition or the low-range SOC correction condition is satisfied, the SOC of the battery is determined according to the temperature of the battery, including:

[0071] If it is determined that the high-segment SOC correction condition or the low-segment SOC correction condition is met, then the SOC-open circuit voltage (OCV) curve of the battery is determined according to the temperature of the battery;

[0072] The SOC of the battery corresponding to the current OCV of the battery is determined according to the SOC-OCV curve of the battery as the determined SOC.

[0073] The OCV of a battery is the terminal voltage of the battery in an open circuit state. The SOC-OCV curve of a battery represents the corresponding relationship between SOC and OCV during the charge and discharge process of the battery. When the battery is not in a charging or discharging state, the SOC of the battery will also change with changes in temperature. For example, when the temperature of the battery is 30°C, the SOC of the battery is 30%. When the temperature of the battery increases to 35°C, the SOC of the battery increases to 31%. For example, when the temperature is 40°C, the SOC of the battery is 40%. When the temperature of the battery drops to 20°C, the SOC of the battery is 37%. Therefore, different battery temperatures can correspond to different SOC-OCV curves, that is, the corresponding relationship between SOC and OCV can change with changes in temperature.

[0074] After determining that the high-segment SOC correction condition or the low-segment SOC correction condition is met, the SOC-OCV curve of the battery can be determined according to the battery temperature. After determining the SOC-OCV curve of the battery, the current OCV of the battery can be obtained, and the SOC of the battery corresponding to the current OCV is determined in the determined SOC-OCV curve as the determined SOC. The SOC corresponding to the current OCV takes into account the influence of the battery temperature on the battery SOC and is closer to the actual SOC.

[0075] In this embodiment, the SOC-OCV curve of the battery is determined according to the battery temperature, and the SOC of the battery corresponding to the current OCV of the battery is determined according to the SOC-OCV curve of the battery. The effect of temperature on the battery SOC is taken into account, and the battery SOC can be accurately and reliably determined.

[0076] In yet another embodiment, the above-mentioned determining the SOC-OCV curve of the battery according to the temperature of the battery includes:

[0077] The SOC-OCV curve corresponding to the battery temperature is found in a predetermined second corresponding relationship as the SOC-OCV curve of the battery. The second corresponding relationship includes a corresponding relationship between the battery temperature and the battery SOC-OCV curve.

[0078] The second corresponding relationship between the battery temperature and the battery SOC-OCV curve can be preset by the designer according to the test. For example, when the battery temperature is 0-10°C, the SOC-OCV curve is determined to be the first SOC-OCV curve; when the battery temperature is 10-20°C, the SOC-OCV curve is determined to be the second SOC-OCV curve; when the battery temperature is greater than 20°C, the SOC-OCV curve is determined to be the third SOC-OCV curve.

[0079] In this embodiment, a table lookup method is adopted to quickly determine the SOC-OCV curve corresponding to the current battery temperature. The method is simple and the data processing speed is fast.

[0080] In another embodiment, if the SOC of the battery currently output is greater than a predetermined SOC threshold, determining whether the high-segment SOC correction condition is met according to the battery cell voltage includes:

[0081] When the vehicle is powered on, the vehicle's sleep time threshold is determined based on the battery temperature;

[0082] If the timing time from the last time the vehicle was powered off is greater than the determined sleep time threshold, and the currently outputted battery SOC is greater than the SOC threshold, it is determined whether the high-segment SOC correction condition is met based on the battery cell voltage.

[0083] When the vehicle is powered on, the VCU of the vehicle will first perform a fault self-check on each component of the vehicle. If it is determined that no fault has occurred, the vehicle will be powered on. Therefore, the battery temperature can be obtained 1 second after the vehicle is powered on and the VCU determines that no fault has occurred.

[0084] The battery will be polarized when working, and it will take a while for the vehicle to recover to a stable state after it is powered off. The sleep time threshold represents the time it takes for the battery to recover to a stable state after the vehicle is powered off. When the time from the last time the vehicle was powered off is greater than the determined sleep time threshold, it can be considered that the battery has recovered to a stable state, and it is more accurate to perform SOC correction at this time.

[0085] Since the time required for the battery to return to a stable state after the vehicle is powered off is highly correlated with the battery temperature, different battery temperatures may correspond to different sleep time thresholds. For example, the correspondence between the battery temperature and the sleep time threshold may be set in advance through an experimental method, and the sleep time threshold corresponding to the battery temperature may be found in the correspondence as the vehicle's sleep time threshold. The battery temperature and the sleep time threshold may have a negative correlation. For example, when the battery temperature is -20°C, the sleep time threshold is determined to be 2h; when the battery temperature is -10°C, the sleep time threshold is determined to be 1.5h; when the battery temperature is -5°C, the sleep time threshold is determined to be 1.2h; when the battery temperature is 25°C, the sleep time threshold is determined to be 1h.

[0086] In this embodiment, the vehicle's sleep time threshold is determined based on the battery temperature to determine whether the high-segment SOC correction condition is met. This is performed under the conditions that the timing time since the vehicle was last powered off is greater than the determined sleep time threshold, and the current output battery SOC is greater than the SOC threshold. This reduces the impact of the battery polarization phenomenon on the correction result and improves the correction accuracy.

[0087] In another embodiment, if the time length from the last time the vehicle was powered off is greater than the determined sleep time length threshold, and the SOC of the battery currently output is greater than the SOC threshold, then judging whether the high-segment SOC correction condition is met according to the battery cell voltage includes:

[0088] If the timing time since the vehicle was last powered off is greater than the determined sleep time threshold, the bus current of the vehicle is not greater than the predetermined static current threshold, and the current output SOC of the battery is greater than the SOC threshold, then it is determined whether the high-segment SOC correction conditions are met based on the battery cell voltage.

[0089] The busbar of the vehicle is the wire leading out from the positive and negative poles of the vehicle's power battery, and the busbar current of the vehicle is the current at the positive and negative poles of the power battery. The static current threshold can be preset by the designer, for example, it can be 2A. When the busbar current of the vehicle is not greater than the predetermined static current threshold, it can be considered that the vehicle is powered on but not in driving state, the battery has not yet supplied power to the outside, and the battery has not been polarized.

[0090] In this embodiment, it is determined whether the high-range SOC correction condition is met, and is further limited to be executed when the bus current of the vehicle is not greater than a predetermined static current threshold, thereby improving the accuracy of the correction.

[0091] In yet another embodiment, judging whether the high-range SOC correction condition is met according to the battery cell voltage includes: if the battery cell voltage is greater than a predetermined first voltage threshold, judging that the high-range SOC correction condition is met.

[0092] In this embodiment, the above-mentioned determination of whether the low-segment SOC correction condition is met based on the battery cell voltage includes: if the battery cell voltage is greater than a predetermined second voltage threshold, it is determined that the low-segment SOC correction condition is met, and the first voltage threshold is greater than the second voltage threshold.

[0093] The first voltage threshold can be preset by the designer, for example, it can be 3V. When the battery SOC is in the high-segment SOC, when the battery cell voltage is less than the first voltage threshold, the difference between the battery SOCs corresponding to different battery cell voltages is small, and the necessity to correct the output SOC is not great, and the effect is not obvious, so no correction is required; when the battery cell voltage is greater than the first voltage threshold, the difference between the battery SOCs corresponding to different battery cell voltages is large, and the effect of correcting the battery SOC is obvious. At this time, it can be determined that the high-segment SOC correction condition is met.

[0094] Similar to the correction of the high-range SOC mentioned above, when the battery SOC is in the low-range SOC, when the battery cell voltage is less than the second voltage threshold, the difference between the battery SOCs corresponding to different battery cell voltages is small, and there is little need to correct the output SOC, and the effect is not obvious, so no correction is required; when the battery cell voltage is greater than the second voltage threshold, the difference between the battery SOCs corresponding to different battery cell voltages is large, and the effect of correcting the battery SOC is obvious. At this time, it can be determined that the low-range SOC correction conditions are met.

[0095] In this embodiment, whether the high-range SOC correction condition or the low-range SOC correction condition is satisfied is simply determined based on the threshold comparison result, and the data processing speed is fast and the reliability is high.

[0096] In yet another embodiment, the method of determining the correction speed according to the difference between the determined battery SOC and the currently outputted battery SOC includes:

[0097] In a predetermined third corresponding relationship, a correction coefficient corresponding to a difference between the determined battery SOC and the currently output battery SOC is found;

[0098] The correction speed is determined according to the following formula:

[0099] V=(S k+1 -S k ) / Δt=K*I / Q

[0100] Where V is the corrected speed, K is the correction coefficient, I is the bus current of the vehicle, Q is the rated capacity of the battery, S k+1 is the SOC of the (k+1)th correction cycle, S k is the SOC of the kth correction cycle, and Δt is the duration of the correction cycle.

[0101] The correction cycle may be a predetermined time length, such as 1 second. The correction is performed once in each correction cycle until the determined battery SOC is reached, or the difference between the determined battery SOC and the currently output battery SOC is less than a preset value, then the correction ends.

[0102] The correction coefficient determines the speed of the correction. The larger the correction coefficient, the faster the correction speed, and the smaller the correction coefficient, the slower the correction speed. The third corresponding relationship can be preset by the designer based on the test. After determining the difference between the battery SOC and the current output battery SOC, the correction coefficient can be determined according to the third corresponding relationship, and then the correction speed can be calculated by the above formula.

[0103] In this embodiment, the correction speed can be quickly calculated according to the above formula, the method is simple, and the data processing speed is fast.

[0104] Figure 2 is a flow chart of a battery SOC correction method provided by yet another exemplary embodiment. Figure 2 The steps in the embodiment are a combination of the steps in the above multiple embodiments, and specifically include the following steps.

[0105] 1. When the vehicle is powered on, the vehicle's sleep time threshold is determined based on the battery temperature.

[0106] 2. If the timing time from the last time the vehicle was powered off is greater than the determined sleep time threshold, the bus current of the vehicle is not greater than 2A (static current threshold), the current output SOC of the battery is less than 50% (SOC threshold), and the battery cell voltage is greater than 3V (second voltage threshold), then find the SOC-OVC curve corresponding to the battery temperature in the predetermined second corresponding relationship as the SOC-OVC curve of the battery.

[0107] 3. Determine the SOC of the battery corresponding to the current OCV of the battery based on the SOC-OVC curve of the battery.

[0108] 4. In the predetermined third corresponding relationship, find the correction coefficient corresponding to the difference between the determined battery SOC and the currently output battery SOC.

[0109] 5. According to the formula V = (S k+1 -S k ) / Δt=K*I / Q determines the correction speed.

[0110] 6. According to the determined correction speed, the SOC of the battery currently output is corrected.

[0111] 7. If the time from when the vehicle was last powered off is less than the determined sleep time threshold, the SOC of the battery currently output is not corrected.

[0112] 8. If the bus current of the vehicle is greater than 2A, the SOC of the current output battery will not be corrected.

[0113] 9. If the timing time from the last time the vehicle was powered off is greater than the determined sleep time threshold, the bus current of the vehicle is not greater than 2A, the current output SOC of the battery is greater than 50%, and the battery cell voltage is greater than 3.8V (first voltage threshold), then find the SOC-OVC curve corresponding to the battery temperature in the predetermined second corresponding relationship as the SOC-OVC curve of the battery.

[0114] 10. Determine the SOC of the battery corresponding to the current OCV of the battery based on the SOC-OVC curve of the battery.

[0115] 11. In the predetermined third corresponding relationship, find a correction coefficient corresponding to the difference between the determined battery SOC and the currently output battery SOC.

[0116] 12. According to the formula V = (S k+1 -S k ) / Δt=K*I / Q determines the correction speed.

[0117] 13. According to the determined correction speed, the SOC of the battery currently output is corrected.

[0118] 14. If the timing time from the last time the vehicle was powered off is greater than the determined sleep time threshold, the bus current of the vehicle is not greater than 2A, the SOC of the current output battery is greater than 50%, and the battery cell voltage is less than 3.8V, the SOC of the current output battery will not be corrected.

[0119] 15. If the timing time from the last time the vehicle was powered off is greater than the determined sleep time threshold, the bus current of the vehicle is not greater than 2A, the SOC of the current output battery is less than 50%, and the battery cell voltage is less than 3V, then the SOC of the current output battery will not be corrected.

[0120] Figure 3 FIG. 1 is a block diagram of a battery SOC correction device provided by an exemplary embodiment. Figure 3 As shown, the battery SOC correction device 300 includes: a first determination module 301 , a second determination module 302 and a correction module 303 .

[0121] The first determination module 301 is used to determine the SOC of the battery according to the temperature of the battery.

[0122] The second determination module 302 is used to determine the correction speed according to the difference between the determined battery SOC and the currently output battery SOC.

[0123] The correction module 303 is used to correct the SOC of the battery currently output according to the determined correction speed.

[0124] Optionally, the second determining module 302 includes a first searching submodule.

[0125] The first search submodule is used to search for a correction speed corresponding to a difference between the determined battery SOC and the output battery SOC in a predetermined first corresponding relationship as the determined correction speed.

[0126] Optionally, in the predetermined first corresponding relationship, the greater the difference between the determined battery SOC and the output battery SOC, the greater the corresponding correction speed.

[0127] Optionally, the battery SOC correction device 300 further includes a first judgment module and a second judgment module.

[0128] The first judgment module is used to judge whether a high-segment SOC correction condition is met according to the battery cell voltage when the vehicle is powered on if the SOC of the battery currently output is greater than a predetermined SOC threshold.

[0129] The second judgment module is used to judge whether the low-segment SOC correction condition is met according to the battery cell voltage if the currently outputted battery SOC is less than the SOC threshold.

[0130] The first determining module 301 includes a first determining submodule.

[0131] The first determination submodule is used to determine the SOC of the battery according to the temperature of the battery if it is determined that the high-range SOC correction condition or the low-range SOC correction condition is satisfied.

[0132] Optionally, the first determination submodule is further configured to determine a SOC-open circuit voltage OCV curve of the battery according to the temperature of the battery if it is determined that the high-segment SOC correction condition or the low-segment SOC correction condition is met;

[0133] The SOC of the battery corresponding to the current OCV of the battery is determined according to the SOC-OCV curve of the battery as the SOC of the battery.

[0134] Optionally, the first determination submodule is further used to find out a SOC-OCV curve corresponding to the battery temperature in a predetermined second correspondence as the battery SOC-OCV curve, and the second correspondence includes a correspondence between the battery temperature and the battery SOC-OCV curve.

[0135] Optionally, the first judging module includes a second determining submodule and a judging submodule.

[0136] The second determination submodule is used to determine the vehicle's sleep duration threshold according to the battery temperature when the vehicle is powered on.

[0137] The judgment submodule is used to judge whether the high-segment SOC correction condition is met according to the battery cell voltage if the timing time from the last time the vehicle was powered off is greater than the determined sleep time threshold and the current output battery SOC is greater than the SOC threshold.

[0138] Optionally, the judgment submodule is also used to judge whether the high-segment SOC correction conditions are met based on the battery cell voltage if the timing time starting from the last time the vehicle was powered off is greater than the determined sleep time threshold, the bus current of the vehicle is not greater than a predetermined static current threshold, and the SOC of the battery currently output is greater than the SOC threshold.

[0139] Optionally, the first determination module includes a first determination submodule.

[0140] The first determination submodule is used to determine that a high-range SOC correction condition is met if the cell voltage of the battery is greater than a predetermined first voltage threshold.

[0141] The second judgment module includes a second judgment submodule.

[0142] The second determination submodule is used to determine that the low-segment SOC correction condition is met if the cell voltage of the battery is greater than a predetermined second voltage threshold, and the first voltage threshold is greater than the second voltage threshold.

[0143] Optionally, the second determining module 302 includes a second searching submodule and a calculating submodule.

[0144] The second search submodule is used to search for a correction coefficient corresponding to a difference between the determined battery SOC and the currently output battery SOC in a predetermined third corresponding relationship.

[0145] The calculation submodule is used to determine the correction speed according to the following formula:

[0146] V=(S k+1 -S k ) / Δt=K*I / Q

[0147] Wherein, V is the correction speed, K is the correction coefficient, I is the bus current of the vehicle, Q is the rated capacity of the battery, Sk+1 is the SOC of the (k+1)th correction cycle, Sk is the SOC of the kth correction cycle, and Δt is the duration of the correction cycle.

[0148] Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0149] Through the above technical solution, the SOC of the battery is determined according to the temperature of the battery, the correction speed is determined according to the difference between the determined SOC of the battery and the SOC of the currently output battery, and the SOC of the currently output battery is corrected according to the determined correction speed. In this way, the influence of the battery temperature on the battery SOC is taken into account, and the correction speed is determined according to the difference between the determined SOC of the battery and the SOC of the currently output battery, and an appropriate correction speed matching the difference can be determined, so that the corrected SOC is more accurate and reliable, and the user experience is improved.

[0150] The present disclosure also provides a vehicle, comprising:

[0151] a memory having a computer program stored thereon;

[0152] The processor is used to execute the computer program in the memory to implement the steps of the above-mentioned battery SOC correction method.

[0153] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0154] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0155] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A battery state of charge (SOC) correction method, characterized in that: The method comprises: determining the SOC of the battery according to the temperature of the battery; determining a correction speed according to a difference between the determined SOC of the battery and the currently output SOC of the battery; Correcting the SOC of the battery currently output according to the determined correction speed; When the vehicle is powered on, if the SOC of the battery currently output is greater than a predetermined SOC threshold, it is determined whether the high-segment SOC correction condition is met according to the cell voltage of the battery; If the SOC of the battery currently output is less than the SOC threshold, determining whether the low-segment SOC correction condition is met according to the cell voltage of the battery; Wherein, determining the SOC of the battery according to the temperature of the battery includes: If it is determined that the high-range SOC correction condition or the low-range SOC correction condition is satisfied, determining the SOC of the battery according to the temperature of the battery; Wherein, if the SOC of the battery currently output is greater than a predetermined SOC threshold, judging whether a high-segment SOC correction condition is met according to the cell voltage of the battery, includes: When the vehicle is powered on, determining a sleep time threshold of the vehicle according to the temperature of the battery, the sleep time threshold representing the time required for the battery to recover to a stable state after the vehicle is powered off; If the time length from the last time the vehicle was powered off is greater than the determined sleep time length threshold, and the SOC of the battery currently output is greater than the SOC threshold, determining whether the high-segment SOC correction condition is met based on the cell voltage of the battery; Wherein, determining the correction speed according to the difference between the determined SOC of the battery and the currently output SOC of the battery includes: In a predetermined third corresponding relationship, a correction coefficient corresponding to a difference between the determined SOC of the battery and the currently output SOC of the battery is found; The correction speed is determined according to the following formula: V=(S k+1 -S k ) / Δt=K•I / Q Wherein, V is the correction speed, K is the correction coefficient, I is the bus current of the vehicle, Q is the rated capacity of the battery, S k+1 is the SOC of the (k+1)th correction cycle, S k is the SOC of the kth correction cycle, and Δt is the duration of the correction cycle.

2. The method according to claim 1, characterized in that If it is determined that the high-range SOC correction condition or the low-range SOC correction condition is satisfied, determining the SOC of the battery according to the temperature of the battery includes: If it is determined that the high-segment SOC correction condition or the low-segment SOC correction condition is satisfied, determining the SOC-open circuit voltage (OCV) curve of the battery according to the temperature of the battery; The SOC of the battery corresponding to the current OCV of the battery is determined according to the SOC-OCV curve of the battery as the SOC of the battery.

3. The method according to claim 2, characterized in that The step of determining the SOC-open circuit voltage (OCV) curve of the battery according to the temperature of the battery comprises: A SOC-OCV curve corresponding to the temperature of the battery is searched out in a predetermined second correspondence relationship as the SOC-OCV curve of the battery, wherein the second correspondence relationship includes a correspondence relationship between the temperature of the battery and the SOC-OCV curve of the battery.

4. The method according to claim 1, characterized in that If the time length from the last time the vehicle was powered off is greater than the determined sleep time length threshold, and the SOC of the battery currently output is greater than the SOC threshold, determining whether the high-segment SOC correction condition is met according to the cell voltage of the battery, including: If the timing time starting from the last time the vehicle was powered off is greater than the determined sleep time threshold, the bus current of the vehicle is not greater than the predetermined static current threshold, and the SOC of the battery currently output is greater than the SOC threshold, then it is determined whether the high-segment SOC correction condition is met based on the battery cell voltage.

5. The method according to claim 1, characterized in that The determining whether the high-segment SOC correction condition is met according to the cell voltage of the battery comprises: if the cell voltage of the battery is greater than a predetermined first voltage threshold, determining that the high-segment SOC correction condition is met; The determining whether the low-segment SOC correction condition is met based on the battery cell voltage includes: if the battery cell voltage is greater than a predetermined second voltage threshold, determining that the low-segment SOC correction condition is met, and the first voltage threshold is greater than the second voltage threshold.

6. A vehicle, characterized in that: include: a memory having a computer program stored thereon; A processor, configured to execute the computer program in the memory to implement the steps of the method according to any one of claims 1 to 5.

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