SOC correction method, computer readable storage medium and electronic equipment

Abstract

The invention relates to the technical field of batteries, particularly provides an SOC correction method, a computer readable storage medium and electronic equipment, and aims to solve the problem that the SOC correction accuracy is relatively poor as the condition under a combined working condition is not considered during SOC correction in the prior art. In order to achieve the purpose, the SOC correction method comprises the steps that the calculated SOC, the working condition type and the actual initial SOC of a battery with a composite negative electrode are obtained; based on the working condition type, obtaining a target SOC-OCV test relation corresponding to the actual initial SOC; according to a test relationship between the calculated SOC and the target SOC-OCV, judging whether the calculated SOC is in an OCV commutation interval or not; and if yes, SOC correction is carried out. According to the method, the OCV reversing rule of the combined working condition is considered, SOC correction can be carried out according to the OCV reversing interval and different working condition types, and the SOC correction accuracy can be improved.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and specifically provides a SOC correction method, a computer-readable storage medium and an electronic device. Background Art

[0002] In the prior art, correcting the SOC (State of Charge, battery charge) by looking up the SOC-OCV relationship table based on the open-circuit voltage (OCV) is one of the more classic methods in the SOC estimation method. Among them, the OCV calibration test is usually performed in a simple charging direction and / or a simple discharging direction to obtain the SOC-OCV relationship table. After using the ampere-hour integration to calculate the real-time battery charge, the calculated SOC is statically corrected based on the obtained SOC-OCV relationship table. However, in the prior art, when performing SOC correction, combined operating conditions such as charging to a certain SOC and then discharging or discharging to a certain SOC and then charging are not considered. If the method of looking up the SOC-OCV relationship table obtained based on the simple charging direction and / or the simple discharging direction is still used for the combined operating conditions, the accuracy of the SOC correction is affected. Summary of the invention

[0003] The present invention aims to solve the above technical problem, that is, to solve the problem that the accuracy of SOC correction is poor because the situation under combined working conditions is not taken into consideration when performing SOC correction.

[0004] In a first aspect, the present invention provides a method for correcting SOC, which is applied to a battery with a composite negative electrode, comprising:

[0005] Obtaining the calculated SOC, operating condition type, and actual initial SOC of the battery;

[0006] Based on the operating condition type, obtaining a target SOC-OCV test relationship corresponding to the actual initial SOC;

[0007] According to the calculated SOC and the target SOC-OCV test relationship, determining whether the calculated SOC is in the OCV switching interval;

[0008] In response to the determination being yes, SOC correction is performed.

[0009] In some embodiments, the OCV switching interval is set according to the following steps:

[0010] Obtaining a SOC-OCV standard relationship, and comparing the target SOC-OCV test relationship with the SOC-OCV standard relationship;

[0011] In response to the SOC interval corresponding to the OCV difference in the comparison result, the OCV switching interval is set.

[0012] In some embodiments, the method further includes pre-constructing a SOC-OCV standard relationship, wherein the SOC-OCV standard relationship includes a SOC-OCV standard discharge relationship corresponding to a fully charged to fully discharged condition and a SOC-OCV standard charge relationship corresponding to a fully discharged to fully charged condition.

[0013] In some embodiments, performing SOC correction includes:

[0014] determining a target OCV corresponding to the calculated SOC based on the target SOC-OCV test relationship;

[0015] Acquire a SOC-OCV standard relationship, and determine a standard SOC corresponding to the target OCV based on the SOC-OCV standard relationship;

[0016] The standard SOC is compared with the calculated SOC, and the SOC is corrected according to the comparison result.

[0017] In some embodiments, performing SOC correction includes:

[0018] determining a target OCV corresponding to the calculated SOC based on the target SOC-OCV test relationship;

[0019] Constructing an average standard SOC-OCV relationship based on the standard SOC-OCV discharge relationship and the standard SOC-OCV charge relationship;

[0020] determining a first standard SOC corresponding to the target OCV based on the SOC-OCV standard discharge relationship and the SOC-OCV standard charge relationship, and determining a second standard SOC corresponding to the target OCV based on the SOC-OCV average standard relationship;

[0021] The calculated SOC is compared with the first standard SOC and the second standard SOC respectively, and the SOC is corrected according to the comparison results.

[0022] In some embodiments, before obtaining the target SOC-OCV test relationship corresponding to the actual initial SOC based on the operating condition type, the method further includes:

[0023] A first SOC-OCV test relationship for a charge-to-discharge condition is constructed and / or a second SOC-OCV test relationship for a discharge-to-charge condition is constructed.

[0024] In some embodiments, a first SOC-OCV test relationship is constructed by the following steps:

[0025] Charging the battery to a first test initial SOC and obtaining a first OCV of the battery under a static condition; the first test initial SOC is less than 100%;

[0026] Discharging the battery from the first test initial SOC to 0% in stages, recording the second test initial SOC reached after each discharge stage and obtaining the second OCV of the battery under the current static working condition;

[0027] The first SOC-OCV test relationship corresponding to the first test initial SOC is constructed based on the first test initial SOC, the first OCV, and the second test initial SOC and the second OCV corresponding to each of the discharging stages.

[0028] In some embodiments, the second SOC-OCV test relationship is constructed by the following steps:

[0029] Discharging the battery to a third test initial SOC and obtaining a third OCV of the battery under a static condition; the third test initial SOC is greater than 0%;

[0030] charging the battery in stages from the third test initial SOC to 100%, recording a fourth test initial SOC reached after each charging stage and obtaining a fourth OCV of the battery under a current static working condition;

[0031] The second SOC-OCV test relationship corresponding to the third test initial SOC is constructed based on the third test initial SOC, the third OCV, and the fourth test initial SOC and the fourth OCV corresponding to each of the charging stages.

[0032] In some embodiments, after recording the second test initial SOC reached after each discharge stage and obtaining the second OCV of the battery under the current static working condition, the method further includes:

[0033] Determining whether the second test initial SOC is equal to 0%;

[0034] If yes, updating the first test initial SOC and constructing the first SOC-OCV test relationship corresponding to the updated first test initial SOC;

[0035] If not, the next discharging phase is entered based on the second test initial SOC until the second test initial SOC is equal to 0%.

[0036] In some embodiments, after updating the first test initial SOC and before constructing the first SOC-OCV test relationship corresponding to the updated first test initial SOC, the method further includes:

[0037] Determining whether the updated initial SOC of the first test is equal to a preset discharge test termination charge;

[0038] If yes, the test ends;

[0039] If not, the battery is charged from 0% to the updated first test initial SOC.

[0040] In some embodiments, the method further comprises:

[0041] Obtaining the number of charging times corresponding to the first test initial SOC before updating;

[0042] The updated first test initial SOC is determined according to a difference between the first test initial SOC before updating and a product of a first preset change amount and the number of charging times.

[0043] In some embodiments, after recording the fourth test initial SOC reached after each charging stage and obtaining the fourth OCV of the battery under the current static working condition, the method further includes:

[0044] determining whether the fourth test initial SOC is equal to 100%;

[0045] If yes, updating the third test initial SOC and constructing the second SOC-OCV test relationship corresponding to the updated third test initial SOC;

[0046] If not, the next charging stage is entered based on the fourth test initial SOC until the fourth test initial SOC is equal to 100%.

[0047] In some embodiments, after updating the third test initial SOC and before constructing the second SOC-OCV test relationship corresponding to the updated third test initial SOC, the method further includes:

[0048] Determining whether the updated third test initial SOC is equal to a preset charging test termination charge;

[0049] If yes, the test ends;

[0050] If not, the battery is discharged from 100% to the updated third test initial SOC.

[0051] In some embodiments, the method further comprises:

[0052] Obtaining the number of discharges corresponding to the third test initial SOC before updating;

[0053] The updated third test initial SOC is determined according to the sum of the third test initial SOC before updating and the product of the second preset change amount and the number of discharges.

[0054] In a second aspect, an embodiment of the present invention provides a computer-readable storage medium, wherein a computer program is stored in the computer-readable storage medium, and when the computer program is executed by a processor, the SOC correction method described in any one of the above is implemented.

[0055] In a third aspect, the present invention provides an electronic device, comprising:

[0056] at least one processor;

[0057] and, a memory communicatively coupled to the at least one processor;

[0058] Wherein, a computer program is stored in the memory, and when the computer program is executed by the at least one processor, any one of the above-mentioned SOC correction methods is implemented.

[0059] Solution 1. A SOC correction method, characterized in that the method is applied to a battery with a composite negative electrode, comprising:

[0060] Obtaining the calculated SOC, operating condition type, and actual initial SOC of the battery;

[0061] Based on the operating condition type, obtaining a target SOC-OCV test relationship corresponding to the actual initial SOC;

[0062] According to the calculated SOC and the target SOC-OCV test relationship, determining whether the calculated SOC is within the OCV switching interval;

[0063] In response to the determination being yes, SOC correction is performed.

[0064] Solution 2. The method according to Solution 1 is characterized in that the OCV switching interval is set according to the following steps:

[0065] Obtaining a SOC-OCV standard relationship, and comparing the target SOC-OCV test relationship with the SOC-OCV standard relationship;

[0066] In response to the SOC interval corresponding to the difference in OCV in the comparison result, the OCV switching interval is set.

[0067] Solution 3. The method according to Solution 1 is characterized in that the method also includes pre-building a SOC-OCV standard relationship, and the SOC-OCV standard relationship includes a SOC-OCV standard discharge relationship corresponding to a fully charged to fully discharged condition and a SOC-OCV standard charging relationship corresponding to a fully discharged to fully charged condition.

[0068] Solution 4. The method according to any one of solutions 1 to 3, characterized in that the SOC correction comprises:

[0069] determining a target OCV corresponding to the calculated SOC based on the target SOC-OCV test relationship;

[0070] Acquire a SOC-OCV standard relationship, and determine a standard SOC corresponding to the target OCV based on the SOC-OCV standard relationship;

[0071] The standard SOC is compared with the calculated SOC, and the SOC is corrected according to the comparison result.

[0072] Solution 5. The method according to Solution 3 is characterized in that the SOC correction comprises:

[0073] determining a target OCV corresponding to the calculated SOC based on the target SOC-OCV test relationship;

[0074] Constructing an average standard SOC-OCV relationship based on the standard SOC-OCV discharge relationship and the standard SOC-OCV charge relationship;

[0075] determining a first standard SOC corresponding to the target OCV based on the SOC-OCV standard discharge relationship and the SOC-OCV standard charge relationship, and determining a second standard SOC corresponding to the target OCV based on the SOC-OCV average standard relationship;

[0076] The calculated SOC is compared with the first standard SOC and the second standard SOC respectively, and the SOC is corrected according to the comparison results.

[0077] Solution 6. The method according to Solution 1 is characterized in that, before obtaining the target SOC-OCV test relationship corresponding to the actual initial SOC based on the operating condition type, the method further includes:

[0078] A first SOC-OCV test relationship for a charge-to-discharge condition is constructed and / or a second SOC-OCV test relationship for a discharge-to-charge condition is constructed.

[0079] Solution 7. The method according to Solution 6 is characterized in that the first SOC-OCV test relationship is established by the following steps:

[0080] Charging the battery to a first test initial SOC and obtaining a first OCV of the battery under a static condition; the first test initial SOC is less than 100%;

[0081] Discharging the battery from the first test initial SOC to 0% in stages, recording the second test initial SOC reached after each discharge stage and obtaining the second OCV of the battery under the current static working condition;

[0082] The first SOC-OCV test relationship corresponding to the first test initial SOC is constructed based on the first test initial SOC, the first OCV, and the second test initial SOC and the second OCV corresponding to each of the discharging stages.

[0083] Solution 8. The method according to Solution 6 is characterized in that the second SOC-OCV test relationship is constructed by the following steps:

[0084] Discharging the battery to a third test initial SOC and obtaining a third OCV of the battery under a static condition; the third test initial SOC is greater than 0%;

[0085] charging the battery in stages from the third test initial SOC to 100%, recording a fourth test initial SOC reached after each charging stage and obtaining a fourth OCV of the battery under a current static working condition;

[0086] The second SOC-OCV test relationship corresponding to the third test initial SOC is constructed based on the third test initial SOC, the third OCV, and the fourth test initial SOC and the fourth OCV corresponding to each of the charging stages.

[0087] Solution 9. The method according to Solution 7 is characterized in that after recording the second test initial SOC reached after each discharge stage and obtaining the second OCV of the battery under the current static working condition, the method further includes:

[0088] Determining whether the second test initial SOC is equal to 0%;

[0089] If yes, updating the first test initial SOC and constructing the first SOC-OCV test relationship corresponding to the updated first test initial SOC;

[0090] If not, the next discharging phase is entered based on the second test initial SOC until the second test initial SOC is equal to 0%.

[0091] Solution 10. The method according to Solution 9 is characterized in that, after updating the first test initial SOC and before constructing the first SOC-OCV test relationship corresponding to the updated first test initial SOC, the method further includes:

[0092] Determining whether the updated initial SOC of the first test is equal to a preset discharge test termination charge;

[0093] If yes, the test ends;

[0094] If not, the battery is charged from 0% to the updated first test initial SOC.

[0095] Solution 11. The method according to solution 9 or 10, characterized in that the method further comprises:

[0096] Obtaining the number of charging times corresponding to the first test initial SOC before updating;

[0097] The updated first test initial SOC is determined according to a difference between the first test initial SOC before updating and a product of a first preset change amount and the number of charging times.

[0098] Solution 12. The method according to Solution 8 is characterized in that after recording the fourth test initial SOC reached after each charging stage and obtaining the fourth OCV of the battery under the current static working condition, the method further includes:

[0099] determining whether the fourth test initial SOC is equal to 100%;

[0100] If yes, updating the third test initial SOC and constructing the second SOC-OCV test relationship corresponding to the updated third test initial SOC;

[0101] If not, the next charging stage is entered based on the fourth test initial SOC until the fourth test initial SOC is equal to 100%.

[0102] Solution 13. The method according to Solution 12 is characterized in that, after updating the third test initial SOC and before constructing the second SOC-OCV test relationship corresponding to the updated third test initial SOC, the method further includes:

[0103] Determining whether the updated third test initial SOC is equal to a preset charging test termination charge;

[0104] If yes, the test ends;

[0105] If not, the battery is discharged from 100% to the updated third test initial SOC.

[0106] Solution 14. The method according to solution 12 or 13, characterized in that the method further comprises:

[0107] Obtaining the number of discharges corresponding to the third test initial SOC before updating;

[0108] The updated third test initial SOC is determined according to the sum of the third test initial SOC before updating and the product of the second preset change amount and the number of discharges.

[0109] Solution 15. A computer-readable storage medium, characterized in that a computer program is stored in the computer-readable storage medium, and when the computer program is executed by a processor, the SOC correction method described in any one of Solutions 1 to 14 is implemented.

[0110] Solution 16. An electronic device, comprising:

[0111] at least one processor;

[0112] and, a memory communicatively coupled to the at least one processor;

[0113] Wherein, a computer program is stored in the memory, and when the computer program is executed by the at least one processor, the SOC correction method described in any one of Schemes 1 to 14 is implemented.

[0114] In the case of adopting the above technical solution, the present invention can be applied to batteries with composite negative electrodes, by obtaining the calculated SOC, operating condition type and actual initial SOC of the battery; based on the operating condition type, obtaining the target SOC-OCV test relationship corresponding to the actual initial SOC; judging whether the calculated SOC is within the OCV commutation interval according to the calculated SOC and the target SOC-OCV test relationship; and performing SOC correction in response to a yes judgment result. This method takes into account the OCV commutation law of the combined operating condition when the SOC-OCV standard discharge relationship corresponding to the fully charged to fully discharged operating condition and the SOC-OCV standard charging relationship corresponding to the fully discharged to fully charged operating condition do not overlap, and can perform SOC correction for the OCV commutation interval and different operating condition types, which is beneficial to improving the accuracy of SOC correction. BRIEF DESCRIPTION OF THE DRAWINGS

[0115] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings, in which:

[0116] Figure 1 It is a schematic flow chart of the main steps of a SOC correction method provided by an embodiment of the present invention;

[0117] Figure 2 It is a schematic diagram of the SOC-OCV test relationship of the combined working condition provided by an embodiment of the present invention;

[0118] Figure 3 is a flow chart of a method for setting an OCV commutation interval provided by an embodiment of the present invention;

[0119] Figure 4 is a flow chart of a SOC correction method provided by an embodiment of the present invention;

[0120] Figure 5 is a schematic diagram of a local SOC-OCV test relationship of an embodiment of the present invention;

[0121] Figure 6 is a flow chart of a SOC correction method provided by another embodiment of the present invention;

[0122] Figure 7 is a flow chart of a method for constructing a first SOC-OCV test relationship provided by an embodiment of the present invention;

[0123] Figure 8 is a flowchart of a method for constructing multiple first SOC-OCV test relationships provided by a specific example of the present invention;

[0124] Fig. 9 is a schematic flow chart of a method for constructing a second SOC-OCV test relationship provided by an embodiment of the present invention;

[0125] Fig.10 is a flowchart of a method for constructing multiple second SOC-OCV test relationships provided by a specific example of the present invention;

[0126] Fig.11 It is a schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0127] Some embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0128] As described in the background technology section, the prior art usually performs OCV calibration tests in a simple charging direction and / or a simple discharging direction to construct a SOC-OCV relationship table without considering the situation under combined working conditions. Due to the difference in battery electrode materials, in some cases, there will be differences in the corresponding OCV when the same SOC value is taken for the OCV-SOC relationship obtained for the simple charging direction and the SOC-OCV relationship obtained for the simple discharging direction. Furthermore, for combined working conditions such as charging first and then discharging or discharging first and then charging, when the charge and discharge working condition conversion occurs, the corresponding OCV value at a certain SOC does not belong to the value of the SOC-OCV relationship obtained in the simple charging direction nor the value of the SOC-OCV relationship obtained in the simple discharging direction. If the SOC correction is still performed based on the SOC-OCV relationship obtained in the simple charging direction and / or the SOC-OCV relationship obtained in the simple discharging direction in the prior art, the error is large, which affects the accuracy of the SOC correction. In view of this, the present invention provides an SOC correction method, and the specific description can be referred to below.

[0129] See also Figure 1 As shown, Figure 1 1 is a flow chart of the main steps of a SOC correction method provided by an embodiment of the present invention, which can be applied to a battery with a composite negative electrode. The method comprises:

[0130] Step S11: Obtain the calculated SOC, operating condition type, and actual initial SOC of the battery;

[0131] Step S12: based on the operating condition type, obtaining a target SOC-OCV test relationship corresponding to the actual initial SOC;

[0132] Step S13: judging whether the calculated SOC is within the OCV switching interval according to the calculated SOC and the target SOC-OCV test relationship;

[0133] Step S14: In response to the judgment result being yes, SOC correction is performed.

[0134] In some embodiments, the calculated SOC of the battery in step S11 may be obtained by using an ampere-hour integration method. In other embodiments, other conventional methods in the art may be used to obtain the calculated SOC.

[0135] In some embodiments, the battery of the composite negative electrode may include a ternary lithium battery with a negative electrode doped with silicon. Specifically, a graphite doped with silicon material may be used as the negative electrode. When the negative electrode uses a graphite doped with silicon material, the difference between the charging OCV and the discharging OCV is large, that is, there will be a SOC-OCV relationship obtained in a pure charging direction and a SOC-OCV relationship obtained in a pure discharging direction, and there will be a situation where the corresponding OCV is different at the same SOC.

[0136] It should be noted that the SOC-OCV test relationship is constructed for an initial SOC greater than 0% and less than 100%, while the SOC-OCV standard relationship is constructed for a fully charged to fully discharged condition, i.e., an initial SOC=100%, and / or for a fully discharged to fully charged condition, i.e., an initial SOC=0%. The SOC-OCV standard relationship includes a SOC-OCV standard discharge relationship obtained for a fully charged to fully discharged condition and / or a SOC-OCV standard charge relationship obtained for a fully discharged to fully charged condition.

[0137] In some embodiments, the operating condition type may include a charge-to-discharge operating condition and / or a discharge-to-charge operating condition, and the actual initial SOC may be greater than 0% and less than 100%. Different operating condition types may correspond to the same or different actual initial SOCs.

[0138] In some embodiments, when the operating condition type is a charge-to-discharge condition, the actual initial SOC may be the SOC reached after charging, and the SOC is used as the SOC for starting discharge for discharge; when the operating condition type is a discharge-to-charge condition, the actual initial SOC may be the SOC reached after discharge, and the SOC is used as the SOC for starting charge for charging. As an example, when the operating condition type is a charge-to-discharge condition, the actual initial SOC may be 85%; when the operating condition type is a discharge-to-charge condition, the actual initial SOC may be 5%.

[0139] In some embodiments, before executing step S12, SOC-OCV test relationships corresponding to different operating conditions and different initial SOCs may be pre-constructed. For details, please refer to the description of constructing the first SOC-OCV test relationship for the charge-to-discharge operating condition and / or constructing the second SOC-OCV test relationship for the discharge-to-charge operating condition below.

[0140] Step S12 may specifically be to determine the target SOC-OCV test relationship from a plurality of pre-constructed first SOC-OCV test relationships and / or second SOC-OCV test relationships corresponding to different test initial SOCs according to the operating condition type and the actual initial SOC.

[0141] by Figure 2 For example, Figure 2 The first SOC-OCV test relationship S corresponding to the first test initial SOC of 85% is shown in FIG. 21 , and the operating condition type is the discharge-to-charge operating condition, and the initial SOC of the third test is 5% corresponding to the second SOC-OCV test relationship S 11When the current operating condition type is discharge-to-charge and the actual initial SOC is 5%, the second SOC-OCV test relationship S can be determined. 11 Test the relationship for target SOC-OCV.

[0142] In some embodiments, before executing step S13, see Figure 3 As shown, Figure 3 is a flow chart of a method for setting an OCV commutation interval provided by an embodiment of the present invention, which may include:

[0143] Step S31: obtaining a SOC-OCV standard relationship, and comparing the target SOC-OCV test relationship with the SOC-OCV standard relationship;

[0144] Step S32: In response to the SOC interval corresponding to the difference in OCV in the comparison result, the SOC interval is set as the OCV switching interval.

[0145] In some embodiments, the method provided by the embodiment of the present invention may further include pre-building a SOC-OCV standard relationship. The SOC-OCV standard relationship may include: a SOC-OCV standard charging relationship corresponding to a fully discharged to fully charged condition, such as Figure 2 Medium S 10 As shown in FIG. 1 , and the SOC-OCV standard discharge relationship corresponding to the fully charged to fully discharged condition, as shown in FIG. Figure 2 Medium S 20 shown.

[0146] In some embodiments, step S31 may be specifically to determine whether the OCV determined by the target SOC-OCV test relationship and the SOC-OCV standard relationship are the same when the SOC is the same. If the OCV is different, the corresponding SOC interval is the OCV switching interval. Figure 2 For example, when the target SOC-OCV test relationship is the first SOC-OCV test relationship S 21 When the target SOC-OCV test relationship is the second SOC-OCV test relationship S 11 When the OCV commutation interval is 5% to 20% of the SOC corresponding interval, the OCV commutation interval can be determined to perform SOC correction for different SOC intervals, thereby overcoming the problem of poor accuracy of correction in the prior art that combined working conditions and OCV commutation rules are not considered and the SOC-OCV relationship obtained in the pure charging direction and / or the SOC-OCV relationship obtained in the pure discharging direction is directly looked up in a table.

[0147] In some embodiments, see Figure 4 As shown, Figure 4is a flow chart of a SOC correction method provided by an embodiment of the present invention. Step S14 can be performed by Figure 4 The following steps are shown to achieve:

[0148] Step S41: determining a target OCV corresponding to the calculated SOC based on a target SOC-OCV test relationship;

[0149] Step S42: obtaining a SOC-OCV standard relationship, and determining a standard SOC corresponding to the target OCV based on the SOC-OCV standard relationship;

[0150] Step S43: Compare the standard SOC and the calculated SOC, and correct the SOC according to the comparison result.

[0151] In some embodiments, see Figure 5 As shown, Figure 5 Schematic diagram of the local SOC-OCV test relationship of an embodiment of the present invention, which includes S 10 , S 20 , S 11 and S 21 Part of.

[0152] When the target SOC-OCV test relationship is S 11 And when the SOC is 6%, the corresponding S 11 Point A in the figure, the ordinate corresponding to point A is taken as the target OCV; when the calculated SOC is 18%, the corresponding S 11 Point B in the figure, the ordinate corresponding to point B is taken as the target OCV; when the calculated SOC is 12%, the corresponding S 11 Point C in the figure, the ordinate corresponding to point C is taken as the target OCV; when the calculated SOC is 8%, the corresponding S 11 Point D in the figure takes the ordinate corresponding to point D as the target OCV.

[0153] In some embodiments, step S42 may be specifically based on the SOC-OCV standard charging relationship S 10 Determine a standard SOC corresponding to the target OCV, and / or, based on a SOC-OCV standard discharge relationship S 20 Determine the standard SOC corresponding to the target OCV.

[0154] As an example, Figure 5 As shown, based on the SOC-OCV standard discharge relationship S 20 Determine the standard SOC corresponding to the target OCV at point A, that is, the target OCV at S 20 The corresponding horizontal axis SOC value of point A1. Based on the SOC-OCV standard charging relationship S 10 Determine the standard SOC corresponding to the target OCV at point B, that is, the target OCV at S10 The corresponding horizontal axis SOC value of point B1.

[0155] In some embodiments, step S43 may specifically be to correct the calculated SOC based on the standard SOC in response to the absolute value of the difference between the quasi-SOC and the calculated SOC being less than or equal to a preset threshold, wherein the preset threshold may be set as required, and as an example, the preset threshold may be 1%.

[0156] In some embodiments, the SOC correction of the calculated SOC based on the standard SOC may be to calculate the average of the standard SOC and the calculated SOC, and use the average as the final SOC. In other embodiments, other conventional methods in the art may also be used to correct the calculated SOC based on the standard SOC.

[0157] In other embodiments, step S43 may be specifically that in response to the absolute value of the difference between the standard SOC and the calculated SOC being greater than a preset threshold, the calculated SOC is not corrected and the standard SOC is calculated as the final SOC. Figure 5 As shown, for points between point A and point B, no SOC correction will be performed.

[0158] In other embodiments, see Figure 6 As shown, Figure 6 is a flow chart of a SOC correction method provided by another embodiment of the present invention. Step S14 can be performed by Figure 6 The following steps are shown to achieve:

[0159] Step S61: determining a target OCV corresponding to the calculated SOC based on a target SOC-OCV test relationship;

[0160] Step S62: constructing an average standard SOC-OCV relationship based on the standard SOC-OCV discharge relationship and the standard SOC-OCV charge relationship;

[0161] Step S63: determining a first standard SOC corresponding to the target OCV based on the SOC-OCV standard discharge relationship and the SOC-OCV standard charge relationship, and determining a second standard SOC corresponding to the target OCV based on the SOC-OCV average standard relationship;

[0162] Step S64: Compare the calculated SOC with the first standard SOC and the second standard SOC respectively, and perform SOC correction according to the comparison results.

[0163] Step S61 can be implemented in the same way as step S41, which will not be described here for brevity. For details, please refer to the above description.

[0164] In some embodiments, step S62 may specifically be to calculate the OCV corresponding to each SOC in the SOC-OCV standard discharge relationship and the SOC-OCV standard charge relationship and calculate the average value, and construct the SOC-OCV average standard relationship with the average value and the corresponding SOC, such as Figure 5 S0 in.

[0165] In some embodiments, determining the first standard SOC corresponding to the target OCV based on the SOC-OCV standard discharge relationship and the SOC-OCV standard charge relationship in step S63 can be implemented using the same method as step S42, which will not be repeated here for the sake of brevity.

[0166] As an example, Figure 5 As shown, the standard SOC corresponding to the target OCV at point C can be determined based on the average SOC-OCV standard relationship S0, that is, the horizontal coordinate SOC value of the target OCV at point C1 corresponding to S0. Alternatively, the standard SOC corresponding to the target OCV at point D can be determined based on the average SOC-OCV standard relationship S0, that is, the horizontal coordinate SOC value of the target OCV at point D1 corresponding to S0.

[0167] In some embodiments, step S64 may specifically include:

[0168] In response to an absolute value of a difference between the first standard SOC and the calculated SOC being less than or equal to a preset threshold, performing SOC correction on the calculated SOC based on the first standard SOC;

[0169] In response to an absolute value of a difference between the second standard SOC and the calculated SOC being less than or equal to a preset threshold, performing SOC correction on the calculated SOC based on the second standard SOC;

[0170] In response to the absolute values ​​of the differences between the calculated SOC and the first standard SOC and the second standard SOC being greater than the preset threshold, the calculated SOC will not be corrected.

[0171] As an example, Figure 5As shown, when the calculated SOC and the first standard SOC correspond to point A and point A1 respectively, and the absolute value of the difference between the SOCs corresponding to point A and point A1 is less than or equal to the preset threshold, the calculated SOC can be corrected based on the SOC corresponding to point A1. Similarly, the calculated SOC can be corrected based on the SOC corresponding to point B1. When the calculated SOC and the second standard SOC correspond to point C and point C1 respectively, and the absolute value of the difference between the SOCs corresponding to point C and point C1 is less than or equal to the preset threshold, the calculated SOC can be corrected based on the SOC corresponding to point C1. Similarly, the calculated SOC can also be corrected based on the SOC corresponding to point D1. For points A and D and between C and B, the absolute values ​​of the differences between the calculated SOC and the first standard SOC and the second standard SOC are greater than the preset threshold, and the calculated SOC of this area will not be corrected.

[0172] The above is a SOC correction method provided by the present invention, which can be used for batteries with composite negative electrodes, by obtaining the calculated SOC, operating condition type and actual initial SOC of the battery; based on the operating condition type, obtaining the target SOC-OCV test relationship corresponding to the actual initial SOC; judging whether the calculated SOC is in the OCV commutation interval according to the calculated SOC and the target SOC-OCV test relationship; and performing SOC correction in response to a yes judgment result. This method takes into account the OCV commutation law of the combined operating condition when the SOC-OCV standard discharge relationship corresponding to the fully charged to fully discharged operating condition and the SOC-OCV standard charging relationship corresponding to the fully discharged to fully charged operating condition do not overlap, and can perform SOC correction for the OCV commutation interval and different operating condition types, which is beneficial to improving the accuracy of SOC correction.

[0173] In some other embodiments, before step S12, the method may further include: constructing a first SOC-OCV test relationship of a charge-to-discharge condition and / or constructing a second SOC-OCV test relationship of a discharge-to-charge condition.

[0174] See also Figure 7 As shown, Figure 7 : is a schematic flow chart of a method for establishing a first SOC-OCV test relationship provided by an embodiment of the present invention, which may include:

[0175] Step S71: charging the battery to a first test initial SOC and obtaining a first OCV of the battery under a static condition; the first test initial SOC is less than 100%;

[0176] Step S72: discharging the battery from the first test initial SOC to 0% in stages, recording the second test initial SOC reached after each discharge stage, and obtaining the second OCV of the battery under the current static working condition;

[0177] Step S73: constructing a first SOC-OCV test relationship corresponding to the first test initial SOC based on the first test initial SOC, the first OCV, and the second test initial SOC and the second OCV corresponding to each discharge stage.

[0178] In some embodiments, obtaining the first OCV of the battery under static conditions in step S71 may specifically be to leave the battery at rest for a first preset time and obtain the first OCV of the battery after the first preset time. In some embodiments, constant current discharge may be performed, for example, constant current discharge may be performed with a charge of 0.33C, and the first preset time may be 30h.

[0179] In some embodiments, discharging the battery from the first test initial SOC to 0% in stages in step S72 may specifically be discharging the battery from the first test initial SOC in stages, wherein the discharge capacity corresponding to each discharge stage may be the same. As an example, the first test initial SOC may be 95%, and the discharge capacity corresponding to each stage may be 5%, so that 95% and multiple second test initial SOCs such as 90%, 85%...5% and multiple second OCVs corresponding to the second test initial SOCs may be obtained in sequence.

[0180] In some embodiments, after recording the second test initial SOC reached after each discharge stage and obtaining the second OCV of the battery under the current static working condition in step S72, the following may also be included:

[0181] Determine whether the second test initial SOC is equal to 0%;

[0182] If yes, updating the first test initial SOC and constructing a first SOC-OCV test relationship corresponding to the updated first test initial SOC;

[0183] If not, the next discharge phase is entered based on the second test initial SOC until the second test initial SOC equals 0%.

[0184] In some embodiments, after updating the first test initial SOC and before constructing a first SOC-OCV test relationship corresponding to the updated first test initial SOC, the method further includes:

[0185] Determine whether the updated first test initial SOC is equal to the preset discharge test termination charge;

[0186] If yes, the test ends;

[0187] If not, charge the battery from 0% to the updated first test initial SOC.

[0188] In some embodiments, the method may further include:

[0189] Obtaining the number of charging times corresponding to the first test initial SOC before updating;

[0190] The updated first test initial SOC is determined according to the difference between the first test initial SOC before updating and the product of the first preset change amount and the number of charging times.

[0191] In some other embodiments, after the first test initial SOC is updated, the charging times may also be updated.

[0192] As a specific example, Figure 8 As shown, Figure 8 It is a flowchart of a method for constructing multiple first SOC-OCV test relationships provided by a specific example of the present invention. The charging times Numer=1 can be recorded first, and the battery with a composite negative electrode of 95% SOC is charged at a constant current of 0.33C to the first test initial SOC, and the first test initial SOC_X is set to 95%. The first OCV is recorded after the battery with a composite negative electrode of 95% SOC is left to stand for 3 hours, and then discharged at a discharge capacity of 5% SOC to obtain a second test initial SOC of 90%. The second OCV is recorded after the battery with a current SOC of 90% is left to stand for 3 hours. Determine whether the current SOC is equal to 0. If not, continue to discharge at a discharge capacity of 5%, and record the second test initial SOC value after the discharge stage as 85%. The battery with a current SOC of 85% is left to stand for 3 hours and the second OCV is recorded. Similarly, the steps of discharging, standing, recording the second OCV, and determining whether the SOC is equal to 0% are cyclically executed until SOC=0. SOCs of 95%, 90%, 85%, ..., 5%, and 0% and the OCVs corresponding to the respective SOCs may be obtained, thereby constructing a first SOC-OCV test relationship corresponding to the first test initial SOC of 95% SOC.

[0193] When it is determined that the current SOC = 0%, the first test initial SOC and the number of charges can also be updated. Specifically, the updated setting SOC_X = SOC_X-Number*5%, and the updated Number = Number+1. Determine whether the updated setting SOC_X is equal to the preset discharge test termination charge of 5%. If so, the test is over; if not, charge the battery from 100% to the updated setting SOC_X at a constant current of 0.33C, and let the battery charged to the updated setting SOC_X stand for 3 hours, record the first OCV, and then discharge in stages at a discharge capacity of 5% until SOC = 0, so that the first SOC-OCV test relationship corresponding to the updated first test initial SOC can be obtained. The steps of determining whether the updated setting SOC_X is equal to the preset discharge test termination charge of 5%, charging from 0% to the updated setting SOC_X, and testing the first SOC-OCV test relationship corresponding to the updated first test initial SOC are executed cyclically until the updated setting SOC_X is equal to the preset discharge test termination charge of 5%. Thus, the first SOC-OCV test relationships corresponding to a plurality of different first test initial SOCs can be obtained.

[0194] See also Fig. 9 As shown, Fig. 9 : is a schematic flow chart of a method for constructing a second SOC-OCV test relationship provided by an embodiment of the present invention, which may include:

[0195] Step S91: discharging the battery to a third test initial SOC and obtaining a third OCV of the battery under static conditions; the third test initial SOC is greater than 0%;

[0196] Step S92: charging the battery from the third test initial SOC to 100% in stages, recording the fourth test initial SOC reached after each charging stage and obtaining the fourth OCV of the battery under the current static working condition;

[0197] Step S93: constructing a second SOC-OCV test relationship corresponding to the third test initial SOC based on the third test initial SOC, the third OCV, and the fourth test initial SOC and the fourth OCV corresponding to each charging stage.

[0198] In some embodiments, after recording the fourth test initial SOC reached after each charging stage and obtaining the fourth OCV of the battery under the current static working condition in step S92, the following may also be included:

[0199] Determining whether the fourth test initial SOC is equal to 100%;

[0200] If yes, updating the third test initial SOC and constructing a second SOC-OCV test relationship corresponding to the updated third test initial SOC;

[0201] If not, the next charging stage is entered based on the fourth test initial SOC until the fourth test initial SOC is equal to 100%.

[0202] In some embodiments, after updating the third test initial SOC and before constructing a second SOC-OCV test relationship corresponding to the updated third test initial SOC, the method further includes:

[0203] Determine whether the updated third test initial SOC is equal to the preset charging test termination charge;

[0204] If yes, the test ends;

[0205] If not, discharge the battery from 100% to the updated third test initial SOC.

[0206] In some embodiments, the method may further include:

[0207] Obtaining the number of discharges corresponding to the third test initial SOC before updating;

[0208] The updated third test initial SOC is determined according to the sum of the third test initial SOC before updating and the product of the second preset change amount and the number of discharges.

[0209] The second preset change amount may be the same as or different from the first preset change amount, and may be set according to specific requirements.

[0210] As a specific example, Fig.10 As shown, Fig.10It is a flowchart of a method for constructing multiple second SOC-OCV test relationships provided by a specific example of the present invention. The discharge number Numer=1 can be recorded first, and the battery with a composite negative electrode of the current 5% SOC is discharged at a constant current of 0.33C to the third test initial SOC, and the third test initial SOC_X is set to 5%. The third OCV is recorded after the battery with the current 10% SOC is left to stand for 3 hours, and then charged with a 5% SOC charging capacity to obtain a fourth test initial SOC of 10%. The fourth OCV is recorded after the battery with the current 10% SOC is left to stand for 3 hours. Determine whether the current SOC is equal to 100%. If not, continue to charge with a 5% SOC charging capacity, and record the fourth test initial SOC value after the charging stage as 15%. The fourth OCV is recorded after the battery with the current 15% SOC is left to stand for 3 hours. Similarly, the steps of charging, standing, recording the fourth OCV, and determining whether the SOC is equal to 100% are cyclically executed until SOC=100%. SOCs of 5%, 10%, 15%, ..., 95%, and 100% and the OCVs corresponding to the respective SOCs may be obtained, thereby constructing a second SOC-OCV test relationship corresponding to the third test initial SOC of 5% SOC.

[0211] When it is determined that the current SOC=100%, the third test initial SOC and the number of discharges can also be updated, specifically the updated setting SOC_X=SOC_X+Number*5%, the updated Number=Number+1. Determine whether the updated setting SOC_X is equal to the preset charge test termination charge of 95%. If so, the test is over; if not, discharge the battery from 0% to the updated setting SOC_X at a constant current of 0.33C, and let the battery discharged to the updated setting SOC_X stand for 3 hours, record the third OCV, and then perform staged charging with a charging capacity of 5% until SOC=100%, so as to obtain the second SOC-OCV test relationship corresponding to the updated third test initial SOC. The steps of determining whether the updated setting SOC_X is equal to the preset charge test termination charge of 95%, discharging from 100% to the updated setting SOC_X, and testing the second SOC-OCV test relationship corresponding to the updated third test initial SOC are executed cyclically until the updated setting SOC_X is equal to the preset charge test termination charge of 95%. Thus, the second SOC-OCV test relationships corresponding to a plurality of different third test initial SOCs can be obtained.

[0212] By constructing the first SOC-OCV test relationship and / or the second SOC-OCV test relationship based on the above method, the SOC-OCV test relationship under the combined working condition can be obtained for the case where the SOC-OCV standard discharge relationship and the SOC-OCV standard charge relationship do not overlap, and the OCV commutation law can be further determined to obtain the OCV commutation interval. This is conducive to correcting different SOC intervals separately when performing SOC correction, thereby improving the accuracy of SOC correction.

[0213] It is understood by those skilled in the art that all or part of the processes in the method for implementing the above-mentioned embodiments of the present invention can also be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a computer-readable storage medium, and when the computer program is executed by a processor, the steps of each of the above-mentioned method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable storage medium may include: any entity or device, medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory, random access memory, electric carrier signal, telecommunication signal and software distribution medium, etc. that can carry the computer program code.

[0214] In another aspect of the present invention, a computer-readable storage medium is provided, in which a computer program is stored, and when the computer program is executed by a processor, the SOC correction method described in any of the above embodiments is implemented. The computer-readable storage medium may be a storage device formed by various electronic devices. Optionally, the computer-readable storage medium in the embodiment of the present invention is a non-temporary computer-readable storage medium.

[0215] Another aspect of the present invention provides an electronic device, which may include at least one processor; and a memory communicatively connected to the at least one processor; wherein a computer program is stored in the memory, and when the computer program is executed by the at least one processor, the SOC correction method described in any of the above embodiments is implemented.

[0216] See also Fig.11 As shown, Fig.11 exemplarily shows a structure in which the memory 101 and the processor 102 are connected via a bus, and only one of the memory 101 and the processor 102 is provided.

[0217] In other embodiments, the electronic device may include multiple memories 101 and multiple processors 102. The program for executing the SOC correction method of any of the above embodiments may be divided into multiple subprograms, each of which may be loaded and run by the processor 102 to execute different steps of the SOC correction method of the above method embodiment. Specifically, each subprogram may be stored in different memories 101, and each processor 102 may be configured to execute the programs in one or more memories 101 to jointly implement the SOC correction method of the above method embodiment.

[0218] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A SOC correction method, characterized in that: The method is applied to a battery with a composite negative electrode, comprising: Obtaining the calculated SOC, operating condition type, and actual initial SOC of the battery; Based on the operating condition type, obtaining a target SOC-OCV test relationship corresponding to the actual initial SOC; According to the calculated SOC and the target SOC-OCV test relationship, determining whether the calculated SOC is within the OCV switching interval; In response to the determination being yes, SOC correction is performed.

2. The method according to claim 1, characterized in that The OCV commutation interval is set according to the following steps: Obtaining a SOC-OCV standard relationship, and comparing the target SOC-OCV test relationship with the SOC-OCV standard relationship; In response to the SOC interval corresponding to the difference in OCV in the comparison result, the OCV switching interval is set.

3. The method according to claim 1, characterized in that The method also includes pre-constructing a SOC-OCV standard relationship, wherein the SOC-OCV standard relationship includes a SOC-OCV standard discharge relationship corresponding to a fully charged to fully discharged condition and a SOC-OCV standard charge relationship corresponding to a fully discharged to fully charged condition.

4. The method according to any one of claims 1 to 3, characterized in that The SOC correction comprises: determining a target OCV corresponding to the calculated SOC based on the target SOC-OCV test relationship; Acquire a SOC-OCV standard relationship, and determine a standard SOC corresponding to the target OCV based on the SOC-OCV standard relationship; The standard SOC is compared with the calculated SOC, and the SOC is corrected according to the comparison result.

5. The method according to claim 3, characterized in that: The SOC correction comprises: determining a target OCV corresponding to the calculated SOC based on the target SOC-OCV test relationship; Constructing an average standard SOC-OCV relationship based on the standard SOC-OCV discharge relationship and the standard SOC-OCV charge relationship; determining a first standard SOC corresponding to the target OCV based on the SOC-OCV standard discharge relationship and the SOC-OCV standard charge relationship, and determining a second standard SOC corresponding to the target OCV based on the SOC-OCV average standard relationship; The calculated SOC is compared with the first standard SOC and the second standard SOC respectively, and the SOC is corrected according to the comparison results.

6. The method according to claim 1, characterized in that Before obtaining the target SOC-OCV test relationship corresponding to the actual initial SOC based on the operating condition type, the method further includes: A first SOC-OCV test relationship for a charge-to-discharge condition is constructed and / or a second SOC-OCV test relationship for a discharge-to-charge condition is constructed.

7. The method according to claim 6, characterized in that The first SOC-OCV test relationship is constructed by the following steps: Charging the battery to a first test initial SOC and obtaining a first OCV of the battery under a static condition; the first test initial SOC is less than 100%; Discharging the battery from the first test initial SOC to 0% in stages, recording the second test initial SOC reached after each discharge stage and obtaining the second OCV of the battery under the current static working condition; The first SOC-OCV test relationship corresponding to the first test initial SOC is constructed based on the first test initial SOC, the first OCV, and the second test initial SOC and the second OCV corresponding to each of the discharging stages.

8. The method according to claim 6, characterized in that The second SOC-OCV test relationship is constructed by the following steps: Discharging the battery to a third test initial SOC and obtaining a third OCV of the battery under a static condition; the third test initial SOC is greater than 0%; charging the battery in stages from the third test initial SOC to 100%, recording a fourth test initial SOC reached after each charging stage and obtaining a fourth OCV of the battery under a current static working condition; The second SOC-OCV test relationship corresponding to the third test initial SOC is constructed based on the third test initial SOC, the third OCV, and the fourth test initial SOC and the fourth OCV corresponding to each of the charging stages.

9. The method according to claim 7, characterized in that: After recording the second test initial SOC reached after each discharge stage and obtaining the second OCV of the battery under the current static working condition, the method further includes: Determining whether the second test initial SOC is equal to 0%; If yes, updating the first test initial SOC and constructing the first SOC-OCV test relationship corresponding to the updated first test initial SOC; If not, the next discharging phase is entered based on the second test initial SOC until the second test initial SOC is equal to 0%.

10. The method according to claim 9, characterized in that After updating the first test initial SOC and before constructing the first SOC-OCV test relationship corresponding to the updated first test initial SOC, the method further includes: Determining whether the updated initial SOC of the first test is equal to a preset discharge test termination charge; If yes, the test ends; If not, the battery is charged from 0% to the updated first test initial SOC.

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