Battery SOC correction method and system, storage medium and vehicle

Abstract

The invention provides a battery SOC correction method, a storage medium, a system and a vehicle. The battery SOC correction method comprises the following steps: acquiring a current vehicle end SOC of a power battery; the current vehicle end SOC is sent to a cloud end, and the cloud end is used for feeding back correction information and a correction instruction when the difference value between the current vehicle end SOC and the current cloud end SOC corresponding to the current vehicle end SOC reaches a preset difference value; the correction information comprises a current cloud SOC; and when the correction instruction is received, correcting the current vehicle end SOC based on the current cloud end SOC. According to the method and the device, the SOC of the cloud end is compared with the SOC of the vehicle end, the accurate SOC is determined according to the comparison result, and then the current SOC of the battery is corrected according to the accurate SOC of the battery, so that the vehicle presents the accurate SOC of the vehicle end battery, and abnormal operation of the vehicle is avoided.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a battery SOC correction method, storage medium, system and vehicle. Background Art

[0002] The battery state of charge (SOC) is used to reflect the current remaining power of the vehicle's power battery, and the battery state of health (SOH) is used to reflect the degradation performance of the battery. During the operation of the power battery, it is necessary to detect the accuracy of the battery SOC in real time. Once the battery SOC is not detected accurately, it is easy to cause abnormal vehicle operation. For example, when the battery SOC is high, the battery SOC is insufficient, but the battery SOC recognized by the vehicle is still sufficient, the vehicle may not be able to drive normally due to insufficient remaining SOC due to misjudgment.

[0003] The above-mentioned problem of inaccurate battery SOC is usually circumvented by correcting the battery SOC; however, in the vehicle's battery SOC correction process, an accurate battery SOC value is required. If the battery SOC used for correction is an inaccurate value, it is difficult to accurately correct the battery SOC.

[0004] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

[0005] The main purpose of the present invention is to provide a battery SOC correction method, storage medium, system and vehicle, aiming to solve the technical problem that it is difficult to accurately correct the battery SOC in the prior art.

[0006] To achieve the above object, the present invention proposes a battery SOC correction method, the battery SOC correction method comprising:

[0007] Get the current vehicle-side SOC of the power battery;

[0008] The current vehicle-side SOC is sent to the cloud, and the cloud is used to feedback correction information and correction instructions when the difference between the current vehicle-side SOC and its corresponding current cloud-side SOC reaches a preset difference; the correction information includes the current cloud-side SOC;

[0009] When the correction instruction is received, the current vehicle-side SOC is corrected based on the current cloud-side SOC.

[0010] Optionally, when receiving the correction instruction, correcting the current vehicle-side SOC based on the current cloud-side SOC includes:

[0011] Detecting a current current of the power battery and a duration of the current current;

[0012] When the current current is not greater than the preset current threshold and the duration reaches the preset duration, the current vehicle-side SOC is adjusted to the current cloud-side SOC.

[0013] Optionally, after detecting the current current of the power battery and the duration of the current current, the method further includes:

[0014] When the current current is greater than a preset current threshold or the duration does not reach a preset duration, detecting a vehicle operation mode and whether the current cloud SOC is within a SOC limit range;

[0015] When the current cloud SOC is within the SOC limit range, determining a battery SOC correction factor according to the vehicle operation mode, the current cloud SOC, and the current vehicle-side SOC;

[0016] The current vehicle-side SOC is corrected according to the battery SOC correction coefficient and the current current.

[0017] Optionally, the correcting the current vehicle-side SOC according to the battery SOC correction coefficient and the current current includes:

[0018] Determining the current direction and current value of the current;

[0019] Determine the corrected SOC within a correction period using the battery SOC correction coefficient, the current value, and the current direction;

[0020] The current vehicle-side SOC is corrected according to the corrected battery SOC within the correction period.

[0021] Optionally, the detecting the vehicle operation mode and whether the current cloud SOC is within the SOC limit range includes:

[0022] When the current cloud-side SOC is not within the SOC limit range, determining a corrected SOC within a correction period according to the vehicle operation mode and the current vehicle-side SOC;

[0023] The current vehicle-side SOC is corrected according to the corrected battery SOC within the correction period.

[0024] Optionally, the correction information further includes: battery model parameters; the current vehicle-side SOC is sent to the cloud, and the cloud is used to feedback the correction information and the correction instruction when the difference between the current vehicle-side SOC and its corresponding current cloud-side SOC reaches a preset difference, and further includes:

[0025] Upon receiving the correction instruction, detecting a correction method of the current vehicle-side SOC;

[0026] When the correction method is a model correction method, the battery model is corrected using the battery model parameters;

[0027] The target vehicle-side SOC is determined according to the modified battery model.

[0028] Optionally, the battery SOC correction method further includes:

[0029] Detect battery storage data in the vehicle;

[0030] When the battery storage data is detected to be abnormal, a flag request is sent to the cloud, wherein the flag request is used to control the cloud to feedback the cloud storage data; the cloud storage data includes the initial cloud SOC;

[0031] When the cloud storage data is received, the SOC of the power battery is corrected by using the initial cloud SOC in the cloud storage data as the initial corrected SOC.

[0032] In addition, to achieve the above-mentioned purpose, the present application also provides a storage medium, on which a battery SOC correction program is stored. When the battery SOC correction program is executed by a processor, the steps of the battery SOC correction method are implemented.

[0033] In addition, to achieve the above-mentioned purpose, the present application also provides a battery SOC correction system, the battery SOC correction system includes: a cloud and a battery management system, and the battery management system is used to execute the battery SOC correction method.

[0034] In addition, to achieve the above-mentioned purpose, the present application also provides a vehicle, which includes the battery SOC correction system.

[0035] The present application provides a battery SOC correction method, storage medium, system and vehicle, the battery SOC correction method includes: obtaining the current vehicle-side SOC of the power battery; sending the current vehicle-side SOC to the cloud, the cloud is used to feedback correction information and correction instructions when the difference between the current vehicle-side SOC and its corresponding current cloud-side SOC reaches a preset difference; the correction information includes the current cloud-side SOC; when the correction instruction is received, the current vehicle-side SOC is corrected based on the current cloud-side SOC. In the present application, the SOC of the cloud and the vehicle are compared, the accurate SOC is determined according to the comparison result, and then the current SOC of the battery is corrected according to the accurate battery SOC, so that the vehicle presents an accurate vehicle-side battery SOC to avoid abnormal vehicle operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0037] Figure 1 A schematic flow chart of a first embodiment of a battery SOC correction method proposed by the present invention;

[0038] Figure 2 A first flow chart of a second embodiment of the battery SOC correction method proposed by the present invention;

[0039] Figure 3 A second flow chart of the second embodiment of the battery SOC correction method proposed by the present invention;

[0040] Figure 4 A third flow chart of the second embodiment of the battery SOC correction method proposed by the present invention;

[0041] Figure 5 A schematic flow chart of a third embodiment of a battery SOC correction method according to the present invention;

[0042] Figure 6 It is a flowchart diagram of a fourth embodiment of a battery SOC correction method proposed by the present invention.

[0043] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0044] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0047] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0048] Reference Figure 1 , Figure 1 This is a flow chart of the first embodiment of the battery SOC correction method proposed in the invention. Figure 1 A first embodiment of a battery SOC correction method of the present invention is provided.

[0049] In a first embodiment, the battery SOC correction method includes:

[0050] Step S10: Obtain the current vehicle-side SOC of the power battery.

[0051] It should be understood that in this embodiment, the executing entity can be the battery management system of the power battery. The battery management system can monitor the usage status, usage time, battery cell temperature and other information of the power battery, and can also interact with the cloud to transmit the power battery data to the cloud for storage or processing, and receive data output from the cloud when the vehicle-side data is lost.

[0052] It should be understood that in the case of long-term use, the vehicle SOC may be inaccurate, and the correction strategy on the vehicle side may not be triggered or the correction may be inaccurate. At this time, the battery SOC in the vehicle may be falsely high or falsely low. The large SOC error may lead to a decline in battery performance, shortened vehicle range, or even vehicle breakdown, causing customer complaints.

[0053] It should be noted that the current vehicle-side SOC is the remaining power of the power battery obtained after the vehicle detects the power battery during normal operation. If the current vehicle-side SOC is falsely low, it may cause the user to believe that the remaining SOC of the power battery is insufficient and the power battery needs to be charged frequently; if the current vehicle-side SOC is falsely high, it may cause the user to misjudge the endurance of the power battery and cause the vehicle to break down on the road.

[0054] In order to avoid the above problems, it is necessary to estimate the current vehicle-side SOC of the power battery in real time during the normal operation of the vehicle. The specific estimation process can be carried out by collecting the output electrical parameters of the power battery, then determining the remaining SOC change value of the power battery according to the change of the electrical parameters of the power battery, and finally determining the current vehicle-side SOC of the power battery according to the initial value and change value of the power battery; of course, the current vehicle-side SOC of the power battery can be estimated by other methods, which are not specifically limited here.

[0055] Step S20: Send the current vehicle-side SOC to the cloud, and the cloud is used to feedback correction information and correction instructions when the difference between the current vehicle-side SOC and its corresponding current cloud-side SOC reaches a preset difference.

[0056] It should be noted that the current cloud SOC refers to the remaining SOC of the power battery obtained by the cloud after the battery SOC estimation model based on the neural network is calculated according to the actual vehicle data. The preset difference is a pre-set difference used to determine whether the current vehicle-side SOC has a false high or false low abnormality. For example, the preset difference is 5%. If the SOC difference between the current vehicle-side SOC and the current cloud-side SOC reaches 5%, it is determined that the current vehicle-side SOC is abnormal. Correction information refers to the information required to correct the current vehicle-side SOC for a false high or false low abnormality. The correction information may include information such as the current cloud SOC and the current cloud degradation rate. Of course, when the SOC difference between the current vehicle-side SOC and the current cloud SOC is very small, for example, less than 1%, it can be determined that the current vehicle-side SOC does not have a false high or false low abnormality. The correction instruction is an instruction used to control the power battery system to start correcting the remaining SOC of the power battery.

[0057] It should be understood that a battery SOC estimation model based on a neural network is set up in the cloud, through which a relatively accurate remaining SOC of the power battery can be obtained. In order to determine whether the current vehicle-side SOC is falsely high or falsely low, it is necessary to compare the current vehicle-side SOC with the current cloud-side SOC, and determine whether the current vehicle-side SOC is abnormal based on the difference between the two and the preset difference. If there is an abnormality, correction information and correction instructions can be fed back.

[0058] Step S30: When the correction instruction is received, the current vehicle-side SOC is corrected based on the current cloud-side SOC.

[0059] It should be understood that, when the correction instruction and correction information are received, the current vehicle-side SOC can be directly corrected according to the current cloud-side SOC. The specific correction process can be to adjust the current vehicle-side SOC to the current cloud-side SOC. This process can be adjusted directly in a short time according to the actual situation, or it can be adjusted according to a certain period, which is not specifically limited here.

[0060] This embodiment provides a battery SOC correction method, which includes: obtaining the current vehicle-side SOC of the power battery; sending the current vehicle-side SOC to the cloud, and the cloud is used to feedback correction information and correction instructions when the difference between the current vehicle-side SOC and its corresponding current cloud-side SOC reaches a preset difference; the correction information includes the current cloud-side SOC; when the correction instruction is received, the current vehicle-side SOC is corrected based on the current cloud-side SOC. By comparing the SOC of the cloud and the vehicle, the accurate SOC is determined according to the comparison result, and then the current SOC of the battery is corrected according to the accurate battery SOC, so that the vehicle presents an accurate vehicle-side battery SOC to avoid abnormal vehicle operation.

[0061] Reference Figure 2 , Figure 2 This is a first flow chart of the second embodiment of the battery SOC correction method of the present application. The step S30 specifically includes:

[0062] Step S31: Detect the current current of the power battery and the duration of the current current.

[0063] It should be understood that when correcting the current vehicle-side SOC, the specific method for correcting the current vehicle-side SOC of the power battery can be determined according to the output state of the power battery. For example, when the power battery is in the process of discharging to provide power to the vehicle, directly correcting the current vehicle-side battery SOC to the current cloud SOC may cause a sudden change in the output power of the power battery, thereby resulting in a poor driving experience for the user. Of course, when the vehicle is not driving, the power battery does not need to output a large power. At this time, directly adjusting the current vehicle-side SOC to the current cloud SOC will not affect the user's driving experience.

[0064] Therefore, when correcting the current vehicle-side SOC, it is necessary to determine the output state of the power battery. Among them, the current current is the current output or input of the power battery in the current working state. The duration is used to accurately determine the duration of the power battery output state. When the current current is small, it can be preliminarily determined that the power battery has no need for high-power input or output. In order to avoid accidental situations, accidental situations can be eliminated based on the duration of the current current to obtain the accurate power output requirements of the power battery. The duration can be set according to the user's car usage habits. For example, when waiting for a traffic light, it can be set to 1min.

[0065] In a specific implementation, the current output by the power battery can be collected, and the duration of the current can be recorded at the same time, so that the current current and the duration of the current current can be obtained.

[0066] Step S32: When the current current is not greater than a preset current threshold and the duration reaches a preset duration, the current vehicle-side SOC is adjusted to the current cloud-side SOC.

[0067] It should be understood that when the current current is not greater than the preset current threshold, it can be determined that the power battery has no need for high-power input or output. At the same time, when the duration reaches the preset duration, it can be determined that the power battery does not have a request for high-power output or input, and the vehicle may be in an idling state. At this time, the current vehicle-side SOC can be directly adjusted to the current cloud SOC, which can quickly complete the adjustment of the current vehicle-side SOC without affecting the user experience.

[0068] Reference Figure 3 , Figure 3 After step S31 in the second flow chart of the second embodiment of the battery SOC correction method of the present application, the method further includes:

[0069] Step S33: When the current current is greater than a preset current threshold or the duration does not reach a preset duration, detect the vehicle operation mode and whether the current cloud SOC is within a SOC limit range.

[0070] It should be noted that the vehicle operation mode is the mode corresponding to the current working state of the vehicle, that is, the mode of the input or output power demand of the power battery. The operation mode can be a vehicle running mode, a vehicle charging mode, a vehicle shutdown mode, etc. The SOC limit range refers to the range of the SOC that the power battery can reach during the charging or discharging process. For example, the charging process can charge the SOC of the power battery to 95%, and the discharging process can release the SOC of the power battery to 10%, then the SOC limit range is [10% to 95%]. When the current cloud SOC is within the SOC limit range, it can be determined that the power battery is not overcharged or over-discharged, and the current cloud SOC is not abnormal, and the current cloud SOC can be directly used to correct the current vehicle-side SOC; on the contrary, when the current cloud SOC is not within the SOC limit range, there may be a situation of overcharge or over-discharge of the power battery, or the current vehicle-side SOC of the power battery is abnormal, and then it can be determined whether the current vehicle-side SOC needs to be corrected according to the current cloud SOC. For example, in the vehicle driving mode, the power battery is over-discharged, causing the current cloud SOC to be lower than the lower limit of the SOC limit range. In order to avoid the impact of long-term over-discharge on the power battery, the current vehicle-side SOC of the power battery can be directly adjusted to the lower limit as soon as possible.

[0071] In a specific implementation, when it is determined that the current current is greater than the preset current threshold or the duration does not reach the preset duration, that is, when the power battery has a large power demand, the vehicle operation mode can be detected first, and then the current cloud SOC is compared with the upper limit and lower limit of the SOC limit range, respectively, to determine the vehicle operation mode and whether the current cloud SOC is within the SOC limit range.

[0072] Step S34: When the current cloud SOC is within the SOC limit range, a battery SOC correction factor is determined according to the vehicle operation mode, the current cloud SOC and the current vehicle-side SOC.

[0073] It is understandable that when it is determined that the current cloud SOC is within the SOC limit range, it is determined that the current cloud SOC is normal and the power battery is not over-discharged or over-charged. Considering the power demand of the power battery, it is necessary to slowly adjust the current vehicle-side SOC to reduce the impact on the user's driving experience. In this embodiment, a battery SOC correction factor is also set, which can control the current vehicle-side SOC to be slowly corrected to the current cloud SOC over a period of time, thereby avoiding reducing the user's driving experience.

[0074] It should be noted that since the vehicle operation mode will cause the charging or discharging process of the power battery to change, the current cloud battery SOC correction process target value, the current vehicle-side SOC is the initial value of the correction process. At this time, the battery SOC correction factor can be directly determined according to the vehicle operation mode, the current cloud SOC and the current vehicle-side SOC.

[0075] In a specific implementation, if the vehicle is in driving mode, k = (SOC vehicle - SOC lower limit) / (SOC cloud - SOC lower limit), where k is the correction coefficient, SOC vehicle is the current vehicle-side SOC, SOC lower limit is the lower limit of the SOC limit range, and SOC cloud is the current cloud-side SOC; if the vehicle is in charging mode, k = (SOC upper limit - SOC vehicle) / (SOC upper limit - SOC cloud), where SOC upper limit is the upper limit of the SOC limit range; when the vehicle operating mode is in other modes (non-idle mode, non-driving mode, and non-charging mode), the battery SOC correction coefficient is deemed to be 1.

[0076] Step S35: Correct the current vehicle-side SOC according to the battery SOC correction coefficient and the current current.

[0077] It can be understood that when the battery SOC correction coefficient and the current current are determined, the correction coefficient can be directly used to correct the current current during the entire correction time period, and then the current vehicle-side SOC during the correction process can be determined using the ampere-hour integration method until the current vehicle-side battery SOC is corrected to the current cloud-side SOC.

[0078] The step S35 specifically includes:

[0079] Step S351: Determine the current direction and current value of the current.

[0080] It should be understood that in different operation modes, different current directions require different ways of correcting the current. For example, when the vehicle operation mode is the vehicle running mode, if the current current is the discharge current of the power battery, the correction current for the current current correction process is k*I; if the current current is the charging current of the power battery, the current direction is completely opposite to the discharge current direction, and the correction current for the current current correction process is I / k, that is, when there is energy recovery during the discharge process, the current current can be quickly corrected. For example, the lower limit is 2% and the upper limit is 100%. If the current vehicle-side SOC is too high, the current vehicle-side SOC is 50%; the current cloud-side SOC is 40%; when the vehicle operation mode is the running mode, k = (50-2) / (40-2)>1; at this time, the discharge current is k*I, and the SOC decreases rapidly; the charging current is I / k, and the SOC increases slowly; when the vehicle operation mode is the charging mode, k = (100-50) / (100-40)<1; at this time, the discharge current is I / k, and the SOC decreases rapidly; the charging current is k *I, SOC slows down the increase; similarly, if the current vehicle-side SOC is low, the current vehicle-side SOC is 30%; the current cloud-side SOC is 40%; when the vehicle operation mode is the running mode, k=(30-2) / (40-2)<1; the discharge current is k*I, and the SOC slows down the decrease; the charging current is I / k, and the SOC accelerates the increase; when the vehicle operation mode is the charging mode, k=(100-30) / (100-40)>1; the discharge current is I / k, and the SOC slows down the decrease; the charging current is k*I, and the SOC accelerates the increase.

[0081] Step S352: Determine the corrected SOC within a correction period by using the battery SOC correction coefficient, the current value, and the current direction.

[0082] Step S353: Correct the current vehicle-side SOC according to the corrected battery SOC within the correction period.

[0083] It should be understood that when the battery SOC correction coefficient, the current value and the current direction are determined, the battery SOC correction coefficient, the current value and the current direction can be directly used as parameters for calculation to determine the value of the battery SOC that can be corrected per unit time. When the correction period is determined, the corrected battery SOC within the correction period can be determined. The correction period is a correction time that does not affect the user's driving experience. The correction period is related to the specific corrected battery SOC, that is, the SOC difference between the current vehicle-side SOC and the current cloud-side SOC. Correcting the current vehicle-side SOC within the correction period will not affect the user's driving experience.

[0084] In the specific implementation: if the vehicle operation mode is the running mode, the current current is the discharge current, then SOC(n+1)=SOC(n)-k*abs(I)*T / Q*100; if the current current is the charging current, then SOC(n+1)=SOC(n)+abs(I)*T / Q / k*100, where abs(I) is the absolute value of the current current; Q is the capacity (i.e. the product of the rated capacity and SOH), SOC(n) is the current vehicle-side SOC, SOC(n+1) is the current vehicle-side SOC corrected for one calculation cycle, and T is the calculation cycle. If the vehicle is in the charging mode and the current current is the discharge current, then SOC(n+1)=SOC(n)-abs(I)*T / Q / k*100; if the current current is the charging current, then SOC(n+1)=SOC(n)+k*abs(I)*T / Q*100.

[0085] When the vehicle operation mode is in other modes (non-idle mode, non-driving mode and non-charging mode), k is directly deemed to be 1, and the current vehicle-side SOC is corrected according to SOC(n+1)=SOC(n)-I*T / Q*100, where I is the current current, discharge is a positive value, and charge is a negative value.

[0086] Reference Figure 4 , Figure 4 After step S33 in the third flow chart of the second embodiment of the battery SOC correction method of the present application, the following steps are included:

[0087] Step S36: when the current cloud SOC is not within the SOC limit range, determining a corrected SOC within a correction period according to the vehicle operation mode and the current vehicle-side SOC;

[0088] Step S37: Correcting the current vehicle-side SOC according to the corrected battery SOC within the correction period.

[0089] In a specific implementation, if the vehicle operation mode is the running mode, when the SOC cloud is greater than the SOC lower limit, k = (SOC vehicle - SOC lower limit) / (SOC cloud - SOC lower limit). When the SOC cloud is less than or equal to the SOC lower limit, the current vehicle-side SOC is corrected to the SOC lower limit within T2, and the correction rate k2 = (SOC vehicle - SOC lower limit) / T2, T2 is the correction period when the SOC cloud is less than or equal to the SOC lower limit; at this time, when the current correction period is completed, SOC (n + 1) = SOC (n) - k2 * T. If the vehicle is in charging mode, when the SOC cloud is less than the SOC upper limit, k = (SOC upper limit - SOC car) / (SOC upper limit - SOC cloud); when the SOC cloud is greater than or equal to the SOC upper limit, the current vehicle-side SOC is corrected to the SOC upper limit within T2, and the correction rate k2 = (SOC upper limit - SOC car) / T2, then SOC(n+1) = SOC(n)+k2*T.

[0090] Based on the first embodiment or the second embodiment, a third embodiment of the battery SOC correction method of the present application is proposed.

[0091] Reference Figure 5 , Figure 5 This is a flow chart of a third embodiment of a battery SOC correction method of the present application.

[0092] In this embodiment, the correction information further includes: battery model parameters; after step S20, it also includes:

[0093] Step S201: upon receiving the correction instruction, detecting the correction method of the current vehicle-side SOC.

[0094] It should be understood that the process of correcting the current vehicle-side SOC is not limited to the ampere-hour integration method, and other methods can also be used, but the correction process under different methods is not the same. Therefore, when it is determined that the current vehicle-side SOC needs to be corrected, the correction method of the current vehicle-side SOC can also be detected. Specifically, it can be detected based on the correction method of the current vehicle-side SOC fed back by the battery management system after receiving the correction instruction from the cloud. The battery model parameters may include the battery ohmic internal resistance, the battery polarization internal resistance, and the battery polarization capacitance.

[0095] Step S202: when the correction method is a model correction method, the battery model is corrected using the battery model parameters.

[0096] It can be understood that the model correction method is a method of correcting the current vehicle-side SOC through the model stored in the battery management system. The battery model can be a first-order RC model. When the correction method is determined to be the model correction method, the more accurate battery model parameters output by the cloud can be used to adjust the model parameters in the battery management system to obtain a corrected battery model. In the vehicle running mode, the current vehicle-side SOC is falsely high or falsely low. Since the cloud battery model has been trained a lot, the battery model parameters in the cloud battery model are more accurate. Therefore, the cloud battery model parameters are used to correct the vehicle-side battery model parameters, and then the corrected battery model is used to effectively improve the SOC calculation accuracy.

[0097] Considering the extremely complex characteristics of lithium batteries, it is difficult to conduct full life cycle characteristic testing, modeling and calibration within a limited development cycle. After the battery life decays, the battery model parameters cannot be changed, resulting in poor SOC calculation accuracy in the later stage. Therefore, after the battery model is corrected, the battery model parameters fed back by the cloud can be used as the battery model parameters of the vehicle and stored for further correction of the battery model.

[0098] Step S203: Determine the target vehicle-side SOC according to the modified battery model.

[0099] It should be understood that when the corrected battery model is obtained, the target vehicle-side SOC can be directly determined based on the corrected battery model and the actual vehicle parameters, and then the current vehicle-side battery SOC can be corrected to the target vehicle-side SOC to achieve the correction of the current vehicle-side SOC.

[0100] A fourth embodiment of the battery SOC correction method of the present application is proposed based on any one of the first to third embodiments described above.

[0101] Reference Figure 6 , Figure 6 This is a flow chart of a fourth embodiment of a battery SOC correction method of the present application.

[0102] Battery SOC processing usually includes SOC estimation and SOC correction. The ampere-hour integration method is usually used to estimate the battery SOC. When there is a deviation in the battery SOC, the open circuit voltage method, Kalman filter and other methods can be used to correct the SOC. Since each method has certain shortcomings, the battery SOC estimation and correction process is not accurate. For example, the open circuit voltage method is usually related to the specific type of battery. The voltage of the lithium iron phosphate cell has a platform area, and the SOC cannot be corrected in real time in the entire use range.

[0103] The ampere-hour integration method requires knowing the SOC and SOH of the power battery. Parameters such as the SOC and SOH of the power battery are usually stored inside the vehicle. Once the data stored inside the vehicle is lost or changed, the current SOC and SOH of the power battery cannot be accurately obtained when the vehicle is powered on, making the subsequent ampere-hour integration calculation inaccurate, resulting in large SOC estimation errors or even the inability to estimate the battery SOC.

[0104] In this embodiment, the battery SOC correction method further includes:

[0105] Step S40: Detect the battery storage data in the vehicle.

[0106] It should be noted that the battery storage data is data stored inside the vehicle that reflects the state of the power battery. The battery storage data may include the SOC, SOH, etc. of the battery. Whether the battery storage data is normal directly affects whether the above-mentioned parameter battery state can be used to determine or adjust.

[0107] It is understandable that in the process of estimating SOC using the ampere-hour integration method, the SOC in the battery storage data is required as the initial value, and during the charging or discharging process of the power battery, the SOH value is also required. Therefore, in the case of abnormal battery storage data, it may lead to the inability to accurately estimate the SOC of the power battery.

[0108] In a specific implementation, the battery storage data in the vehicle can be extracted. When the data cannot be extracted normally, the battery storage data can be determined to be abnormal. When the data can be extracted normally, the battery storage data needs to be verified to confirm whether there are abnormalities such as data loss, data errors, etc. When the battery storage data verification fails, the battery storage data can be determined to be abnormal. If the verification passes, the battery storage data is determined to be normal.

[0109] Step S50: When the battery storage data is detected to be abnormal, a flag request is sent to the cloud, wherein the flag request is used to control the cloud to feedback the cloud storage data; the cloud storage data includes an initial cloud SOC.

[0110] It should be noted that when the battery storage data is abnormal, there is nothing in the vehicle that can be used as the basic parameter in the ampere-hour integration, and the SOC cannot be accurately estimated. The cloud refers to the server set up in the cloud space, and the cloud can interact with the battery management system. A data processing model is set up in the cloud, which can determine the SOC and SOH parameters of the power battery in the vehicle in real time when the vehicle's power battery is running. The data processing model set up in the cloud can be a battery SOC estimation model based on a neural network. The model is trained using a large amount of vehicle operation data in the background, and the obtained battery SOC estimation model can determine the SOC of the power battery during the operation of the power battery. The estimation of the battery SOC estimation model can specifically obtain the associated data required for model building and training through background services or data collection, and then clear the abnormal data in the management data, such as null value data or error data; then extract the characteristic factors in the associated data, and use the characteristic factors to build a battery SOC estimation model based on a neural network. The characteristic factors can be the current, voltage, temperature, vehicle status, etc. of the power battery. After the neural network-based battery SOC estimation model is built, it is necessary to use a large amount of related data to train the model to obtain a battery SOC estimation model that meets the accuracy requirements; the battery SOC estimation model after training can accurately estimate the SOC and other parameters of the power battery based on the data of the vehicle in operation.

[0111] It can be understood that the flag request is a signal requesting the cloud to output power battery related parameters. When the battery storage data is abnormal, a flag request can be sent to the cloud, and the cloud can determine that the flag request is 1; of course, when the battery storage data is normal, there is no need to send a flag request, and the cloud can determine that the flag request is 0. Cloud storage data refers to the parameters currently displayed by the power battery, which can include battery SOC, SOH, etc.

[0112] In a specific implementation, when it is confirmed that the battery storage data is abnormal, a flag request can be sent to the cloud. When the cloud receives the flag request or detects that the flag request is 1, it can determine that the battery storage data is abnormal and feedback the cloud storage data.

[0113] Step S60: When the cloud storage data is received, the SOC of the power battery is corrected by using the initial cloud SOC in the cloud storage data as the initial corrected SOC.

[0114] It should be noted that the initial corrected SOC is the initial value for estimating the SOC of the power battery. For example, if the initial corrected SOC is 50% of the current vehicle-side display, and the actual SOC of the power battery is only 40%, the initial corrected SOC needs to be adjusted from 50% to 40% to achieve the battery SOC correction of the power battery.

[0115] It should be understood that when receiving cloud storage data, the SOC and SOH in the cloud storage data can be directly identified as the currently stored SOC and SOH; then the SOC is used to correct the battery SOC in the current state. Of course, considering the prediction of the battery SOC in the vehicle, in the absence of SOH data, the SOH data will be defaulted to 100%, which will lead to inaccurate battery SOC estimation and correction. Therefore, the SOH in the cloud storage data can also be identified as the SOH in the battery storage data, and combined with the currently stored SOH in the subsequent evaluation of the battery SOC.

[0116] In the specific implementation, after the vehicle is powered on again, it is necessary to calculate the initial SOC value first, which will be used as the initial corrected SOC in the subsequent ampere-hour integral calculation formula. The ampere-hour integral method estimates the SOC by integrating current and time, and the initial corrected SOC is required in the calculation formula. Therefore, this embodiment can directly use the received initial cloud SOC as the initial corrected SOC, and then correct the SOC of the power battery according to the initial corrected SOC. For example, using the initial cloud SOC as input, the initial SOC of the battery can be directly corrected and used as the initial SOC in the ampere-hour integral calculation.

[0117] In addition, when the battery storage data is normal, the SOC of the power battery can be corrected by extracting the initial vehicle-side SOC and then using the initial vehicle-side SOC as the initial corrected SOC.

[0118] In order to further ensure the accuracy of the initial corrected SOC, the present embodiment can also use the relationship table between the open circuit voltage and the SOC, collect the open circuit voltage, and then use the relationship table and the open circuit voltage to obtain the table lookup SOC; the initial corrected SOC is selected by the table lookup SOC obtained by looking up the initial vehicle-side SOC stored on the vehicle side and the open circuit voltage. The open circuit voltage is an accurate relationship between voltage and SOC based on the characteristics of the battery cell itself, and it is considered more accurate to use the table lookup SOC as the initial corrected SOC. The cloud-based initial SOC estimation model can also use the relationship between the open circuit voltage and the battery SOC, so it can have the advantages of both the vehicle-side SOC algorithm and the cloud-based algorithm, and has accuracy.

[0119] This embodiment provides a battery SOC correction method, which includes: detecting battery storage data in a vehicle; when the battery storage data is detected to be abnormal, sending a flag request to the cloud, the flag request is used to control the cloud to feedback the cloud storage data; the cloud storage data includes an initial cloud SOC; when the cloud storage data is received, the initial cloud SOC in the cloud storage data is used as the initial correction SOC to correct the SOC of the power battery. When it is confirmed that the battery storage data is abnormal, the cloud storage data can be obtained through the cloud, and then the initial cloud SOC in the cloud storage data is used as the initial correction SOC to correct the SOC of the power battery, so that in the case of loss of storage data, the SOC of the power battery can still be effectively corrected.

[0120] In addition, to achieve the above-mentioned purpose, the present invention further provides a storage medium, on which a battery SOC correction program is stored, and when the battery SOC correction program is executed by a processor, the steps of the battery SOC correction method are implemented.

[0121] In addition, to achieve the above objectives, the present invention also provides a battery SOC correction system, the battery SOC correction system comprising: a cloud and a battery management system, the battery management system being used to execute the battery SOC correction method described in any of the above embodiments.

[0122] In addition, to achieve the above-mentioned purpose, the present invention also provides a vehicle including the battery SOC correction system.

[0123] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A battery SOC correction method, characterized in that: Applied to battery management systems; The battery SOC correction method comprises: Get the current vehicle-side SOC of the power battery; The current vehicle-side SOC is sent to the cloud, and the cloud is used to feedback correction information and correction instructions when the difference between the current vehicle-side SOC and its corresponding current cloud-side SOC reaches a preset difference; the correction information includes the current cloud-side SOC; When the correction instruction is received, the current vehicle-side SOC is corrected based on the current cloud-side SOC.

2. The battery SOC correction method according to claim 1, characterized in that: When the correction instruction is received, correcting the current vehicle-side SOC based on the current cloud-side SOC includes: Detecting a current current of the power battery and a duration of the current current; When the current current is not greater than the preset current threshold and the duration reaches the preset duration, the current vehicle-side SOC is adjusted to the current cloud-side SOC.

3. The battery SOC correction method according to claim 2, characterized in that: After detecting the current current of the power battery and the duration of the current current, the method further includes: When the current current is greater than a preset current threshold or the duration does not reach a preset duration, detecting a vehicle operation mode and whether the current cloud SOC is within a SOC limit range; When the current cloud SOC is within the SOC limit range, determining a battery SOC correction factor according to the vehicle operation mode, the current cloud SOC, and the current vehicle-side SOC; The current vehicle-side SOC is corrected according to the battery SOC correction coefficient and the current current.

4. The battery SOC correction method according to claim 3, characterized in that: The correcting the current vehicle-side SOC according to the battery SOC correction coefficient and the current current includes: Determining the current direction and current value of the current; Determine the corrected SOC within a correction period using the battery SOC correction coefficient, the current value, and the current direction; The current vehicle-side SOC is corrected according to the corrected battery SOC within the correction period.

5. The battery SOC correction method according to claim 3, characterized in that: The detecting the vehicle operation mode and whether the current cloud SOC is within the SOC limit range includes: When the current cloud-side SOC is not within the SOC limit range, determining a corrected SOC within a correction period according to the vehicle operation mode and the current vehicle-side SOC; The current vehicle-side SOC is corrected according to the corrected battery SOC within the correction period.

6. The battery SOC correction method according to claim 1, characterized in that: The correction information also includes: battery model parameters; the current vehicle-side SOC is sent to the cloud, and the cloud is used to feedback the correction information and correction instructions when the difference between the current vehicle-side SOC and its corresponding current cloud-side SOC reaches a preset difference, and further includes: Upon receiving the correction instruction, detecting a correction method of the current vehicle-side SOC; When the correction method is a model correction method, the battery model is corrected using the battery model parameters; The target vehicle-side SOC is determined according to the modified battery model.

7. The battery SOC correction method according to claim 1, characterized in that: The battery SOC correction method further includes: Detect battery storage data in the vehicle; When the battery storage data is detected to be abnormal, a flag request is sent to the cloud, wherein the flag request is used to control the cloud to feedback the cloud storage data; the cloud storage data includes the initial cloud SOC; When the cloud storage data is received, the SOC of the power battery is corrected by using the initial cloud SOC in the cloud storage data as the initial corrected SOC.

8. A storage medium, characterized in that: The storage medium stores a battery SOC correction program, and when the battery SOC correction program is executed by the processor, the steps of the battery SOC correction method according to any one of claims 1 to 7 are implemented.

9. A battery SOC correction system, characterized in that: The battery SOC correction system comprises: a cloud and a battery management system, and the battery management system is used to execute the battery SOC correction method according to any one of claims 1 to 7.

10. A vehicle, characterized in that: The vehicle includes the battery SOC correction system according to claim 9.

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