Method and device for determining residual electric quantity, controller and battery management system

Abstract

The invention provides a residual electric quantity determination method and device, a controller and a battery management system. The remaining capacity determination method comprises the following steps: acquiring charging and discharging times, battery voltage and battery temperature of a battery; a first data table and a second data table corresponding to the charging and discharging times are selected from a plurality of pre-stored data tables, and different data tables are used for indicating the corresponding relation between the residual electric quantity of the battery and the battery voltage and the battery temperature under different charging and discharging times; combining the first data table and the second data table into a third data table; and determining the remaining capacity of the battery according to the battery voltage, the battery temperature and the third data table. Therefore, the residual electric quantity of the battery is determined based on the corresponding relation between the residual electric quantity of the battery and the battery voltage and the battery temperature under different charging and discharging times, the influence of battery aging on the calculation precision of the residual electric quantity is considered, and the calculation precision of the residual electric quantity of the battery is improved.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a method and device for determining remaining power, a controller, and a battery management system. Background Art

[0002] At present, with the significant improvement of battery performance, more and more applications use battery packs to provide energy. In the battery management system, how to accurately estimate the battery's SOC (State of Charge, also known as the remaining power) is the key and difficult point that designers need to consider. Among them, SOC is often expressed as a percentage, SOC = 0 means that the battery is fully discharged, and SOC = 100% means that the battery is fully charged. SOC is widely used. Common photovoltaic energy storage power, mobile phone power, smart watch power, and electric vehicle power are all calculated based on SOC.

[0003] When estimating the SOC of a battery, the complex chemical properties of the battery will affect the accuracy of the SOC estimation. Therefore, the complex application conditions of the battery need to be considered when estimating the SOC. At the same time, multiple variables related to the electrochemical properties need to be introduced, and the SOC estimation method is complicated.

[0004] On this basis, the battery will inevitably age gradually as the charge and discharge process continues to cycle during use. Under the influence of battery aging, the SOC estimation error of the above-mentioned complex SOC estimation method will be increased, resulting in a decrease in the SOC estimation accuracy. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0006] To this end, a first aspect of the present invention is to provide a method for determining remaining power.

[0007] A second aspect of the present invention is to provide a device for determining remaining power.

[0008] A third aspect of the present invention is to provide a controller.

[0009] A fourth aspect of the present invention is to provide a battery management system.

[0010] A fifth aspect of the present invention is to provide a readable storage medium.

[0011] In view of this, according to a first aspect of the present invention, a method for determining a remaining power is proposed, the method comprising: obtaining the number of charge and discharge times of a battery, a battery voltage, and a battery temperature; selecting a first data table and a second data table corresponding to the number of charge and discharge times from a plurality of pre-stored data tables, different data tables being used to indicate the corresponding relationship between the remaining power of the battery and the battery voltage and the battery temperature under different charge and discharge times; merging the first data table and the second data table into a third data table; and determining the remaining power of the battery according to the battery voltage, the battery temperature, and the third data table.

[0012] In the method for determining the remaining power provided by the present invention, in the process of determining the remaining power of the battery, the current number of charge and discharge of the battery, the battery voltage and the battery temperature are obtained, and then according to the current number of charge and discharge of the battery, the first data table and the second data table corresponding to the current number of charge and discharge are selected from the pre-stored multiple data tables. Among them, different data tables are used to indicate the corresponding relationship between the remaining power of the battery and the battery voltage and the battery temperature under different number of charge and discharge, and the first data table and the second data table are respectively data tables corresponding to two number of charge and discharge adjacent to the current number of charge and discharge. On this basis, the first data table and the second data table are merged to obtain the third data table, and then the current remaining power of the battery is determined according to the current battery voltage, battery temperature and the third data table. In this way, based on the current number of charge and discharge, battery voltage and battery temperature of the battery, and the corresponding relationship between the remaining power of the battery and the battery voltage and battery temperature under different number of charge and discharge, the remaining power of the battery is determined, and the influence of battery aging on the calculation accuracy of the remaining power is considered, thereby improving the calculation accuracy of the remaining power of the battery.

[0013] The above-mentioned method for determining the remaining power according to the present invention may also have the following additional technical features:

[0014] In some technical solutions, optionally, a first data table and a second data table corresponding to the number of charge and discharge times are selected from multiple pre-stored data tables, including: based on dichotomy, determining the first value and the second value according to the number of charge and discharge times; selecting a first data table corresponding to the first value and a second data table corresponding to the second value from multiple pre-stored data tables.

[0015] In this technical solution, in the process of selecting the first data table and the second data table corresponding to the current charge and discharge times from the pre-stored multiple data tables, the first value and the second value are determined according to the current charge and discharge times of the battery based on the binary search method, and then the first data table corresponding to the first value and the second data table corresponding to the second value are selected from the pre-stored multiple data tables. In this way, based on the binary search method, two data tables corresponding to two charge and discharge times adjacent to the current charge and discharge times are selected, which ensures the accuracy of the data table selection, and then ensures the accuracy of the subsequent determination of the remaining power.

[0016] In some technical solutions, optionally, the first data table and the second data table are merged into a third data table, including: performing linear interpolation on the first data table and the second data table according to the following formula to obtain the third data table; D3=D1+(D2-D1)×C / (NM); wherein D3 represents the data in the third data table, D1 represents the data in the first data table, D2 represents the data in the second data table, C represents the number of charge and discharge times, M represents the first value, and N represents the second value.

[0017] In this technical solution, in the process of merging the first data table and the second data table to obtain the third data table, the first data table and the second data table are linearly interpolated according to the formula D3=D1+(D2-D1)×C / (NM) to obtain the third data table. Wherein, D3 represents the data in the third data table, D1 represents the data in the first data table, D2 represents the data in the second data table, C represents the number of charge and discharge times, M represents the first value, and N represents the second value. In this way, the accuracy of the obtained third data table is guaranteed, and the accuracy of the subsequent determination of the remaining power based on the third data table is guaranteed.

[0018] In some technical schemes, optionally, the remaining battery power is determined based on the battery voltage, the battery temperature and a third data table, including: when the third data table includes corresponding data for the battery temperature, determining the remaining battery power based on the corresponding relationship indicated by the battery voltage, the battery temperature and the third data table; when the third data table does not include corresponding data for the battery temperature, determining the first temperature and the second temperature based on the battery temperature based on the dichotomy method; performing linear interpolation on the first data corresponding to the first temperature and the second data corresponding to the second temperature in the third data table to obtain the third data; and determining the remaining battery power based on the battery voltage and the third data.

[0019] In this technical solution, in the process of determining the current remaining power of the battery according to the current battery voltage, battery temperature and the third data table of the battery, when the third data table includes the corresponding data of the current battery temperature and the battery voltage, the remaining power of the battery is determined according to the corresponding relationship indicated by the battery voltage, the battery temperature and the third data table. When the third data table includes the corresponding data of the current battery temperature but does not include the corresponding data of the current battery voltage, the remaining power of the battery is determined based on the corresponding data of the current battery temperature in the third data table based on the dichotomy. When the third data table does not include the corresponding data of the current battery temperature, the first temperature and the second temperature are determined based on the dichotomy according to the current battery temperature, and the first data corresponding to the first temperature and the second data corresponding to the second temperature in the third data table are linearly interpolated to obtain the third data, and then the remaining power of the battery is determined based on the battery voltage and the third data. In this way, the calculation accuracy of the remaining power of the battery is improved, and the accuracy of the determined remaining power is guaranteed.

[0020] In some technical solutions, optionally, the method for determining the remaining power also includes: detecting the charge and discharge current of the battery; when the charge and discharge current is less than or equal to the current threshold, counting the battery shelf time until the battery shelf time is greater than the time threshold, and starting the process of determining the remaining power of the battery; when the charge and discharge current is greater than the current threshold, determining the charge power of the battery according to the charge and discharge current; when the charge power is greater than or equal to the power threshold, adding 1 to the number of charge and discharge times of the battery.

[0021] In this technical solution, after the controller starts working, the battery management system enters the working state and detects the charge and discharge current of the battery. When the charge and discharge current is less than or equal to the current threshold, it is determined that the battery is in a shelving state, and the battery shelving time is counted. Then, when the battery shelving time is greater than the time threshold, the process of determining the remaining power of the battery is started, and the remaining power of the battery is updated. Furthermore, when the charge and discharge current is greater than the current threshold, it is determined that the battery is in a charging state, and the charging power of the battery is determined based on the product of the charge and discharge current and the charging time. Then, when the charging power is greater than or equal to the power threshold, the number of charge and discharge times of the battery is increased by 1. In this way, the timeliness of updating the remaining power of the battery and the number of charge and discharge times is guaranteed, and the accuracy of the determined remaining power is improved.

[0022] In some technical solutions, optionally, the method for determining the remaining power also includes: fully charging the battery at different battery temperatures, discharging the battery multiple times according to a preset discharge amount and leaving it standing, recording the battery voltage after each standing until the battery is fully discharged, continuing to fully charge the battery and discharging it according to a preset discharge amount, so as to obtain multiple data tables at different battery temperatures, different charge and discharge times, and different remaining powers.

[0023] In this technical solution, in the process of calibrating the above data table, the battery can be fully charged at the same battery temperature, and then the battery is discharged multiple times according to the preset discharge amount and left to stand, and the battery voltage after each standing is recorded until the battery is fully discharged, and the battery is further fully charged and discharged according to the preset discharge amount to obtain the battery voltage data corresponding to different charge and discharge times and different remaining power at the battery temperature, and then the above data table corresponding to different charge and discharge times is obtained by merging the battery voltage data corresponding to different battery temperatures and different remaining power under the same charge and discharge times. In this way, the influence of battery aging on the calculation accuracy of the remaining power is taken into account, and the calculation accuracy of the remaining power of the battery is improved.

[0024] According to a second aspect of the present invention, a device for determining a remaining power is proposed, the device comprising: an acquisition unit, used to acquire the number of charge and discharge times of a battery, a battery voltage and a battery temperature; the acquisition unit, further used to select a first data table and a second data table corresponding to the number of charge and discharge times from a plurality of pre-stored data tables, different data tables being used to indicate the corresponding relationship between the remaining power of the battery and the battery voltage and the battery temperature under different charge and discharge times; a processing unit, used to merge the first data table and the second data table into a third data table; the processing unit, further used to determine the remaining power of the battery based on the battery voltage, the battery temperature and the third data table.

[0025] The device for determining the remaining power provided by the present invention comprises an acquisition unit and a processing unit. In the process of determining the remaining power of the battery, the acquisition unit acquires the current charge and discharge times, battery voltage and battery temperature of the battery, and then selects the first data table and the second data table corresponding to the current charge and discharge times from a plurality of pre-stored data tables according to the current charge and discharge times of the battery. Among them, different data tables are used to indicate the corresponding relationship between the remaining power of the battery and the battery voltage and the battery temperature under different charge and discharge times, and the first data table and the second data table are respectively data tables corresponding to two charge and discharge times adjacent to the current charge and discharge times. On this basis, the processing unit merges the first data table and the second data table to obtain a third data table, and then determines the current remaining power of the battery according to the current battery voltage, battery temperature and the third data table. In this way, based on the current charge and discharge times, battery voltage and battery temperature of the battery, and the corresponding relationship between the remaining power of the battery and the battery voltage and battery temperature under different charge and discharge times, the remaining power of the battery is determined, the influence of battery aging on the calculation accuracy of the remaining power is taken into account, and the calculation accuracy of the remaining power of the battery is improved.

[0026] According to the third aspect of the present invention, a controller is proposed, comprising a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the method for determining the remaining power in any of the above technical solutions are implemented. Therefore, the controller proposed in the third aspect of the present invention has all the beneficial effects of the method for determining the remaining power in any of the above technical solutions in the first aspect, and will not be repeated here.

[0027] According to the fourth aspect of the present invention, a battery management system is proposed, comprising: the controller in the technical solution of the third aspect above. The battery management system proposed in the fourth aspect of the present invention comprises the controller in the technical solution of the third aspect above. Therefore, the battery management system proposed in the fourth aspect of the present invention has all the beneficial effects of the controller in the technical solution of the third aspect above, which will not be repeated here.

[0028] According to the fifth aspect of the present invention, a readable storage medium is provided, on which a program or instruction is stored, and when the program or instruction is executed by a processor, a method for determining the remaining power in any of the above technical solutions is implemented. Therefore, the readable storage medium provided in the fifth aspect of the present invention has all the beneficial effects of the method for determining the remaining power in any of the technical solutions in the first aspect, and will not be described in detail here.

[0029] Additional aspects and advantages of the present invention will become apparent from the following description or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0031] Figure 1 A schematic diagram of a flow chart of a method for determining the remaining power according to an embodiment of the present invention is shown;

[0032] Figure 2 A second flow chart of a method for determining the remaining power according to an embodiment of the present invention is shown;

[0033] Figure 3 A third flow chart of a method for determining the remaining power according to an embodiment of the present invention is shown;

[0034] Figure 4 A curve diagram showing the relationship between the remaining power and the battery voltage according to an embodiment of the present invention is shown;

[0035] Figure 5 A structural block diagram of a device for determining remaining power according to an embodiment of the present invention is shown;

[0036] Figure 6A structural block diagram of a controller according to an embodiment of the present invention is shown;

[0037] Figure 7 A structural block diagram of a battery management system according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0038] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0039] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0040] Combine the following Figures 1 to 7 , the remaining power determination method and device, controller and battery management system provided in the embodiments of the present application are described in detail through specific embodiments and their application scenarios.

[0041] In one embodiment of the present invention, Figure 1 As shown, the method for determining the remaining power may specifically include the following steps 102 to 108:

[0042] Step 102, obtaining the number of charge and discharge times, battery voltage and battery temperature of the battery;

[0043] Step 104, selecting a first data table and a second data table corresponding to the number of charge and discharge times from a plurality of pre-stored data tables;

[0044] Step 106, merging the first data table and the second data table into a third data table;

[0045] Step 108, determining the remaining power of the battery according to the battery voltage, the battery temperature and the third data table;

[0046] Among them, different data tables are used to indicate the corresponding relationship between the remaining power of the battery and the battery voltage and battery temperature under different charge and discharge times.

[0047] In the method for determining the remaining power provided by the present invention, in the process of determining the remaining power of the battery, the current number of charge and discharge of the battery, the battery voltage and the battery temperature are obtained, and then according to the current number of charge and discharge of the battery, the first data table and the second data table corresponding to the current number of charge and discharge are selected from the pre-stored multiple data tables. Among them, different data tables are used to indicate the corresponding relationship between the remaining power of the battery and the battery voltage and the battery temperature under different number of charge and discharge, and the first data table and the second data table are respectively data tables corresponding to two number of charge and discharge adjacent to the current number of charge and discharge. On this basis, the first data table and the second data table are merged to obtain the third data table, and then the current remaining power of the battery is determined according to the current battery voltage, battery temperature and the third data table. In this way, based on the current number of charge and discharge, battery voltage and battery temperature of the battery, and the corresponding relationship between the remaining power of the battery and the battery voltage and battery temperature under different number of charge and discharge, the remaining power of the battery is determined, and the influence of battery aging on the calculation accuracy of the remaining power is considered, thereby improving the calculation accuracy of the remaining power of the battery.

[0048] Among them, the above-mentioned battery voltage can specifically be the OCV (Open Circuit Voltage) of the battery, and the above-mentioned data table can specifically be an OCV-T-SOC (open circuit voltage-temperature-remaining power) table under different charge and discharge times. One data table corresponds to one charge and discharge number, and one data table contains OCV values ​​corresponding to different temperatures and different remaining powers under the same charge and discharge number.

[0049] For example, the OCV-T-SOC table when the number of charge and discharge times is 0 may be specifically shown in the following Table 1:

[0050] Table 1: OCV-T-SOC table when the number of charge and discharge times is 0

[0051]

[0052] For example, the OCV-T-SOC table with a charge and discharge cycle of 750 times may be specifically shown in the following Table 2:

[0053] Table 2: OCV-T-SOC table when the number of charge and discharge cycles is 750

[0054]

[0055]

[0056] Among them, for the temperature range corresponding to a data table, those skilled in the art can set it according to actual conditions, and no specific limitation is made here.

[0057] In actual application, the battery can be subjected to cycle testing, and then the OCV of the battery can be calibrated at different charge and discharge times, different temperatures and different remaining capacities to obtain a data table corresponding to different charge and discharge times.

[0058] Furthermore, the rated charge and discharge times of the battery are defined as 1500 times. In order to reduce the storage space occupied by the data table, the data table corresponding to the charge and discharge times of 0, 375, 750, 1125 and 1500 can be calibrated for pre-storage, and no specific limitation is made here.

[0059] Furthermore, if Figure 4 As shown, when the SOC is in the range of 20% to 100%, the difference between the SOC-OCV curves of different charge and discharge times is not large, and when the SOC is in the range of 0% to 20%, the difference between the SOC-OCV curves of different charge and discharge times is large. Moreover, in the range of 0% to 20%, the change trend of the SOC-OCV curve is that as the charge and discharge times increase, the OCV corresponding to the same SOC decreases. Based on this, the above calibrated data table is further subjected to differential linearization processing, and only the data table when the charge and discharge times are 0, 750, and 1500 is stored to further save storage space.

[0060] In addition, in actual application, the remaining power determination method proposed in the present invention can be applied not only to traditional SOC estimation methods, but also to ampere-hour integral SOC estimation methods, model estimation SOC methods, etc., to improve the accuracy of SOC estimation.

[0061] In some embodiments of the present invention, optionally, Figure 2 As shown, the above step 104 may specifically include the following steps 104a and 104b:

[0062] Step 104a, determining a first value and a second value according to the number of charge and discharge times based on a dichotomy method;

[0063] Step 104b, selecting a first data table corresponding to the first value and a second data table corresponding to the second value from a plurality of pre-stored data tables.

[0064] In this embodiment, in the process of selecting the first data table and the second data table corresponding to the current charge and discharge times from the pre-stored multiple data tables, the first value and the second value are determined according to the current charge and discharge times of the battery based on the binary search method, and then the first data table corresponding to the first value and the second data table corresponding to the second value are selected from the pre-stored multiple data tables. In this way, based on the binary search method, two data tables corresponding to two charge and discharge times adjacent to the current charge and discharge times are selected, which ensures the accuracy of the data table selection, and further ensures the accuracy of the subsequent determination of the remaining power.

[0065] Exemplarily, the controller pre-stores data tables with charge and discharge times of 0, 750, and 1500, and the current charge and discharge times of the battery is 375. Based on the dichotomy method, two data tables with charge and discharge times of 0 and 1500 are selected from the pre-stored multiple data tables as the first data table and the second data table.

[0066] In some embodiments of the present invention, optionally, the above step 106 may specifically include the following step 106a:

[0067] Step 106a, according to the formula D3=D1+(D2-D1)×C / (NM), linear interpolation is performed on the first data table and the second data table to obtain a third data table;

[0068] Among them, D3 represents the data in the third data table, D1 represents the data in the first data table, D2 represents the data in the second data table, C represents the number of charge and discharge times, M represents the first value, and N represents the second value.

[0069] In this embodiment, in the process of merging the first data table and the second data table to obtain the third data table, the first data table and the second data table are linearly interpolated according to the formula D3=D1+(D2-D1)×C / (NM) to obtain the third data table. Wherein, D3 represents the data in the third data table, D1 represents the data in the first data table, D2 represents the data in the second data table, C represents the number of charge and discharge times, M represents the first value, and N represents the second value. In this way, the accuracy of the obtained third data table is guaranteed, and the accuracy of the subsequent determination of the remaining power based on the third data table is guaranteed.

[0070] For example, the current charge and discharge times C = 375, based on the binary method, the first value M = 0, the second value N = 750, that is, the first data table is the above Table 1, and the second data table is the above Table 2. Based on this, according to the formula D3 = D1 + (D2-D1) × C / (NM), the third data table when the charge and discharge times C = 375 can be obtained, and the third data table is shown in the following Table 3:

[0071] Table 3: OCV-T-SOC table when the number of charge and discharge times is 375

[0072]

[0073] In some embodiments of the present invention, optionally, the above step 108 may specifically include the following steps 108a and 108b:

[0074] Step 108a, when the third data table includes corresponding data of the battery temperature, determining the remaining power of the battery according to the corresponding relationship between the battery voltage, the battery temperature and the third data table;

[0075] Step 108b, when the third data table does not include corresponding data for the battery temperature, determine the first temperature and the second temperature based on the battery temperature based on the dichotomy method; perform linear interpolation on the first data corresponding to the first temperature and the second data corresponding to the second temperature in the third data table to obtain third data; determine the remaining power of the battery based on the battery voltage and the third data.

[0076] In this embodiment, in the process of determining the current remaining capacity of the battery according to the current battery voltage, battery temperature and the third data table of the battery, when the third data table includes the corresponding data of the current battery temperature and the battery voltage, the remaining capacity of the battery is determined according to the corresponding relationship indicated by the battery voltage, the battery temperature and the third data table. When the third data table includes the corresponding data of the current battery temperature but does not include the corresponding data of the current battery voltage, the remaining capacity of the battery is determined according to the corresponding data of the current battery temperature in the third data table based on the dichotomy. When the third data table does not include the corresponding data of the current battery temperature, the first temperature and the second temperature are determined according to the current battery temperature based on the dichotomy, and the first data corresponding to the first temperature and the second data corresponding to the second temperature in the third data table are linearly interpolated to obtain the third data, and then the remaining capacity of the battery is determined according to the battery voltage and the third data. In this way, the calculation accuracy of the remaining capacity of the battery is improved, and the accuracy of the determined remaining capacity is guaranteed.

[0077] For example, the current battery temperature is 10° C. and the battery voltage is 4060 mV. Based on this, it can be directly found from Table 3 that the current remaining battery power is 80%.

[0078] For example, the current battery temperature is 15°C and the battery voltage is 4018mV. The above Table 3 does not include the corresponding data of 15°C. At this time, according to the battery temperature of 15°C, the first data corresponding to 10°C and the second data corresponding to 20°C are found from the above Table 3, and linear interpolation is performed to obtain the third data, and then based on the dichotomy, the remaining power when the battery voltage is 4018mV is determined according to the third data.

[0079] In some embodiments of the present invention, optionally, the above method for determining the remaining power may further include the following steps 110 to 114:

[0080] Step 110, detecting the charge and discharge current of the battery;

[0081] Step 112, when the charge and discharge current is less than or equal to the current threshold, counting the battery shelf time until the battery shelf time is greater than the time threshold, and starting the process of determining the remaining battery power;

[0082] Step 114, when the charge and discharge current is greater than the current threshold, determine the charge capacity of the battery according to the charge and discharge current; when the charge capacity is greater than or equal to the capacity threshold, add 1 to the number of charge and discharge times of the battery.

[0083] In this embodiment, after the controller starts working, the battery management system enters the working state and detects the charge and discharge current of the battery. When the charge and discharge current is less than or equal to the current threshold, it is determined that the battery is in a shelving state, and the battery shelving time is counted. Then, when the battery shelving time is greater than the time threshold, the process of determining the remaining power of the battery is started, and the remaining power of the battery is updated. Further, when the charge and discharge current is greater than the current threshold, it is determined that the battery is in a charging state, and the charging power of the battery is determined based on the product of the charge and discharge current and the charging time. Then, when the charging power is greater than or equal to the power threshold, the number of charge and discharge times of the battery is increased by 1. In this way, the timeliness of updating the remaining power of the battery and the number of charge and discharge times is guaranteed, and the accuracy of the determined remaining power is improved.

[0084] Among them, the specific value of the above current threshold can be set by those skilled in the art according to actual conditions, such as setting the current threshold to 50mA, which is not specifically limited here.

[0085] In some embodiments of the present invention, optionally, the above method for determining the remaining power may further include the following step 116:

[0086] Step 116, fully charge the battery at different battery temperatures, discharge the battery multiple times according to a preset discharge amount and let it stand, record the battery voltage after each standing, until the battery is fully discharged, continue to fully charge the battery and discharge it according to the preset discharge amount, so as to obtain multiple data tables under different battery temperatures, different charge and discharge times and different remaining power.

[0087] In this embodiment, in the process of calibrating the above data table, the battery can be fully charged at the same battery temperature, and then the battery is discharged multiple times according to the preset discharge amount and left to stand, and the battery voltage after each standing is recorded until the battery is fully discharged, and the battery is continuously fully charged and discharged according to the preset discharge amount to obtain the battery voltage data corresponding to different charge and discharge times and different remaining power at the battery temperature, and then the above data table corresponding to different charge and discharge times is obtained by merging the battery voltage data corresponding to different battery temperatures and different remaining power under the same charge and discharge times. In this way, the influence of battery aging on the calculation accuracy of the remaining power is taken into account, and the calculation accuracy of the remaining power of the battery is improved.

[0088] For example, when the battery temperature is 20° C. and the number of charge and discharge times is 0, the battery voltage data corresponding to different remaining capacities are shown in the following Table 4:

[0089] Table 4: Battery voltage data table when battery temperature = 20°C and charge and discharge times = 0

[0090]

[0091]

[0092] For example, when the battery temperature is 20° C. and the number of charge and discharge times is 375, the battery voltage data corresponding to different remaining capacities are shown in the following Table 5:

[0093] Table 5: Battery voltage data table when battery temperature = 20°C and charge and discharge times = 375

[0094]

[0095] For example, when the battery temperature is 20° C. and the number of charge and discharge times is 750, the battery voltage data corresponding to different remaining capacities are shown in the following Table 6:

[0096] Table 6: Battery voltage data table when battery temperature = 20°C and charge and discharge times = 750

[0097]

[0098]

[0099] For example, when the battery temperature is 20° C. and the number of charge and discharge times is 1125, the battery voltage data corresponding to different remaining capacities are shown in the following Table 7:

[0100] Table 7: Battery voltage data table when battery temperature = 20°C and charge and discharge times = 1125

[0101]

[0102] For example, when the battery temperature is 20° C. and the number of charge and discharge cycles is 1500, the battery voltage data corresponding to different remaining capacities are shown in Table 8 below:

[0103] Table 8: Battery voltage data table when battery temperature = 20°C and charge and discharge times = 1500

[0104]

[0105] The preset discharge amount may be 10% or other values. Those skilled in the art may set the specific value of the preset discharge amount according to actual conditions, and no specific limitation is made here.

[0106] Furthermore, the resting time of the battery may be 2 hours or other durations. Those skilled in the art may set the resting time of the battery each time according to actual conditions, and no specific limitation is made here.

[0107] In summary, if Figure 3 As shown, the method for determining the remaining power provided by the present invention may specifically include the following steps 202 to 218:

[0108] Step 202, determine: the battery is in a standby state, if so, execute step 204, if not, execute step 216;

[0109] Step 204, counting the battery shelf time;

[0110] Step 206, determine: battery storage time> time threshold, if yes, execute step 208, if no, execute step 204;

[0111] Step 208, starting a process for determining the remaining power of the battery;

[0112] Step 210, selecting a first data table and a second data table according to the number of charge and discharge times;

[0113] Step 212, performing linear interpolation on the first data table and the second data table to obtain a third data table;

[0114] Step 214, determining the remaining power of the battery according to the battery voltage, the battery temperature and the third data table;

[0115] Step 216, determine: the battery is in a charging state, if so, execute step 218, if not, end the process;

[0116] Step 218: When the charging power of the battery is greater than or equal to the power threshold, the number of times the battery is charged and discharged is increased by 1.

[0117] After step 218 is completed, step 210 is continued.

[0118] In one embodiment of the present invention, a device for determining the remaining power is also provided. Figure 5 As shown, Figure 5 The structure block diagram of the remaining power determination device 300 according to the embodiment of the present invention is shown. The remaining power determination device 300 may specifically include the following acquisition unit 302 and processing unit 304:

[0119] An acquisition unit 302 is used to acquire the number of charge and discharge times of the battery, the battery voltage and the battery temperature;

[0120] The acquisition unit 302 is further used to select a first data table and a second data table corresponding to the number of charge and discharge times from a plurality of pre-stored data tables, and different data tables are used to indicate the corresponding relationship between the remaining power of the battery and the battery voltage and the battery temperature under different charge and discharge times;

[0121] A processing unit 304 is used to merge the first data table and the second data table into a third data table;

[0122] The processing unit 304 is further configured to determine the remaining power of the battery according to the battery voltage, the battery temperature and the third data table.

[0123] The remaining power determination device 300 provided by the embodiment of the present invention includes an acquisition unit 302 and a processing unit 304. In the process of determining the remaining power of the battery, the acquisition unit 302 acquires the current charge and discharge times, battery voltage and battery temperature of the battery, and then selects the first data table and the second data table corresponding to the current charge and discharge times from the pre-stored multiple data tables according to the current charge and discharge times of the battery. Among them, different data tables are used to indicate the corresponding relationship between the remaining power of the battery and the battery voltage and the battery temperature under different charge and discharge times, and the first data table and the second data table are respectively data tables corresponding to two charge and discharge times adjacent to the current charge and discharge times. On this basis, the processing unit 304 merges the first data table and the second data table to obtain a third data table, and then determines the current remaining power of the battery according to the current battery voltage, battery temperature and the third data table. In this way, based on the current charge and discharge times, battery voltage and battery temperature of the battery, and the corresponding relationship between the remaining power of the battery and the battery voltage and battery temperature under different charge and discharge times, the remaining power of the battery is determined, and the influence of battery aging on the calculation accuracy of the remaining power is considered, thereby improving the calculation accuracy of the remaining power of the battery.

[0124] Among them, the above-mentioned battery voltage can specifically be the OCV of the battery, and the above-mentioned data table can specifically be an OCV-T-SOC (open circuit voltage-temperature-remaining power) table under different charge and discharge times. One data table corresponds to one charge and discharge number, and one data table contains OCV values ​​corresponding to different temperatures and different remaining powers under the same charge and discharge number.

[0125] Furthermore, for the temperature range corresponding to a data table, those skilled in the art may set it according to actual conditions, and no specific limitation is made here.

[0126] In actual application, the battery can be subjected to cycle testing, and then the OCV of the battery can be calibrated at different charge and discharge times, different temperatures and different remaining capacities to obtain a data table corresponding to different charge and discharge times.

[0127] Furthermore, the rated charge and discharge times of the battery are defined as 1500 times. In order to reduce the storage space occupied by the data table, the data table corresponding to the charge and discharge times of 0, 375, 750, 1125 and 1500 can be calibrated for pre-storage, and no specific limitation is made here.

[0128] Furthermore, if Figure 4 As shown, when the SOC is in the range of 20% to 100%, the difference between the SOC-OCV curves of different charge and discharge times is not large, and when the SOC is in the range of 0% to 20%, the difference between the SOC-OCV curves of different charge and discharge times is large. Moreover, in the range of 0% to 20%, the change trend of the SOC-OCV curve is that as the charge and discharge times increase, the OCV corresponding to the same SOC decreases. Based on this, the above calibrated data table is further subjected to differential linearization processing, and only the data table when the charge and discharge times are 0, 750, and 1500 is stored to further save storage space.

[0129] In some embodiments of the present invention, optionally, the processing unit 304 is also used to: determine the first value and the second value based on the number of charge and discharge times based on the dichotomy method; the acquisition unit 302 is specifically used to: select a first data table corresponding to the first value and a second data table corresponding to the second value from multiple pre-stored data tables.

[0130] In some embodiments of the present invention, optionally, the processing unit 304 is specifically used to: perform linear interpolation on the first data table and the second data table according to the following formula to obtain a third data table; D3 = D1 + (D2-D1) × C / (NM); wherein D3 represents the data in the third data table, D1 represents the data in the first data table, D2 represents the data in the second data table, C represents the number of charge and discharge times, M represents the first value, and N represents the second value.

[0131] In some embodiments of the present invention, optionally, the processing unit 304 is specifically used to: determine the remaining power of the battery according to the corresponding relationship between the battery voltage, the battery temperature and the indication of the third data table when the third data table includes corresponding data of the battery temperature; determine the first temperature and the second temperature according to the battery temperature based on the dichotomy method when the third data table does not include corresponding data of the battery temperature; perform linear interpolation on the first data corresponding to the first temperature and the second data corresponding to the second temperature in the third data table to obtain third data; and determine the remaining power of the battery according to the battery voltage and the third data.

[0132] In some embodiments of the present invention, optionally, the processing unit 304 is also used to: detect the charge and discharge current of the battery; when the charge and discharge current is less than or equal to the current threshold, count the battery shelf time until the battery shelf time is greater than the time threshold, and start the process of determining the remaining battery power; when the charge and discharge current is greater than the current threshold, determine the charge power of the battery according to the charge and discharge current; when the charge power is greater than or equal to the power threshold, add 1 to the number of charge and discharge times of the battery.

[0133] In some embodiments of the present invention, optionally, the processing unit 304 is also used to: fully charge the battery at different battery temperatures, discharge the battery multiple times according to a preset discharge amount and let it stand, record the battery voltage after each standing until the battery is fully discharged, continue to fully charge the battery and discharge it according to a preset discharge amount, so as to obtain multiple data tables under different battery temperatures, different charge and discharge times and different remaining powers.

[0134] In one embodiment of the present invention, a controller is also provided. Figure 6 As shown, Figure 6 FIG. 4 is a block diagram of a controller 400 according to an embodiment of the present invention. The controller 400 includes:

[0135] Memory 402, where programs or instructions are stored;

[0136] Processor 404, when executing the above program or instruction, implements the steps of the method for determining the remaining power in any of the above embodiments.

[0137] The controller 400 provided in this embodiment includes a memory 402 and a processor 404. When the program or instructions in the memory 402 are executed by the processor 404, the steps of the method for determining the remaining power in any of the above embodiments are implemented. Therefore, the controller 400 has all the beneficial effects of the method for determining the remaining power in any of the above embodiments, which will not be repeated here.

[0138] Specifically, the memory 402 and the processor 404 may be connected via a bus or other means. The processor 404 may include one or more processing units, and the processor 404 may be a central processing unit (CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), and other chips.

[0139] In one embodiment of the present invention, a battery management system is also provided. Figure 7 As shown, Figure 7 FIG. 5 is a block diagram of a battery management system 500 provided in an embodiment of the present invention. The battery management system 500 includes the controller 400 in the above embodiment. Therefore, the battery management system 500 has all the technical effects of the controller 400 in the above embodiment, which will not be described in detail here.

[0140] In one embodiment of the present invention, a readable storage medium is also provided, on which a program or instruction is stored, and when the program or instruction is executed by a processor, the steps of the method for determining the remaining power in any of the above embodiments are implemented.

[0141] The readable storage medium provided in the embodiment of the present invention can implement the steps of the method for determining the remaining power in any of the above embodiments when the program or instruction stored in the medium is executed by the processor. Therefore, the readable storage medium has all the beneficial effects of the method for determining the remaining power in any of the above embodiments, which will not be described in detail here.

[0142] Specifically, the above-mentioned readable storage medium may include any medium capable of storing or transmitting information. Examples of readable storage media include electronic circuits, semiconductor memory devices, read-only memory (ROM), random access memory (RAM), compact disc read-only memory (CD-ROM), flash memory, erasable ROM (EROM), magnetic tape, floppy disk, optical disk, hard disk, optical fiber medium, radio frequency (RF) link, optical data storage device, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0143] In the description of this specification, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance unless otherwise clearly specified and limited; the terms "connection", "installation", "fixation" and the like should be understood in a broad sense, for example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0144] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0145] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0146] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for determining remaining power, characterized in that: include: Obtain the battery charge and discharge times, battery voltage and battery temperature; Selecting a first data table and a second data table corresponding to the charge and discharge times from a plurality of pre-stored data tables, wherein different data tables are used to indicate the corresponding relationship between the remaining power of the battery and the battery voltage and the battery temperature under different charge and discharge times; Merge the first data table and the second data table into a third data table; The remaining power of the battery is determined according to the battery voltage, the battery temperature and the third data table.

2. The method for determining the remaining power according to claim 1, characterized in that: The selecting a first data table and a second data table corresponding to the charge and discharge times from a plurality of pre-stored data tables comprises: Based on a dichotomy method, determining a first value and a second value according to the number of charge and discharge times; The first data table corresponding to the first value and the second data table corresponding to the second value are selected from a plurality of pre-stored data tables.

3. The method for determining the remaining power according to claim 2, characterized in that: The step of merging the first data table and the second data table into a third data table includes: According to the following formula, linear interpolation is performed on the first data table and the second data table to obtain the third data table; D3 = D1 + (D2 - D1) × C / (NM); Among them, D3 represents the data in the third data table, D1 represents the data in the first data table, D2 represents the data in the second data table, C represents the number of charge and discharge times, M represents the first value, and N represents the second value.

4. The method for determining the remaining power according to any one of claims 1 to 3, characterized in that: The determining the remaining power of the battery according to the battery voltage, the battery temperature and the third data table includes: In a case where the third data table includes corresponding data of the battery temperature, determining the remaining power of the battery according to the corresponding relationship between the battery voltage, the battery temperature and the third data table; In a case where the third data table does not include corresponding data of the battery temperature, determining a first temperature and a second temperature according to the battery temperature based on a binary search method; Performing linear interpolation on first data corresponding to the first temperature and second data corresponding to the second temperature in the third data table to obtain third data; The remaining power of the battery is determined according to the battery voltage and the third data.

5. The method for determining the remaining power according to any one of claims 1 to 3, characterized in that: Also includes: Detect the charge and discharge current of the battery; When the charge and discharge current is less than or equal to the current threshold, counting the battery shelf time until the battery shelf time is greater than the time threshold, and starting a process for determining the remaining power of the battery; When the charge and discharge current is greater than the current threshold, determining the charge capacity of the battery according to the charge and discharge current; When the charging power is greater than or equal to the power threshold, the number of times the battery is charged and discharged is increased by 1.

6. The method for determining the remaining power according to any one of claims 1 to 3, characterized in that: Also includes: The battery is fully charged at different battery temperatures, discharged multiple times according to a preset discharge amount and left to stand, and the battery voltage after each standing is recorded until the battery is fully discharged. The battery is further fully charged and discharged according to the preset discharge amount to obtain multiple data tables under different battery temperatures, different charge and discharge times, and different remaining capacities.

7. A device for determining remaining power, characterized in that: include: An acquisition unit, used to acquire the number of charge and discharge times of the battery, the battery voltage and the battery temperature; The acquisition unit is further used to select a first data table and a second data table corresponding to the charge and discharge times from a plurality of pre-stored data tables, and different data tables are used to indicate the corresponding relationship between the remaining power of the battery and the battery voltage and the battery temperature under different charge and discharge times; a processing unit, configured to merge the first data table and the second data table into a third data table; The processing unit is further used to determine the remaining power of the battery according to the battery voltage, the battery temperature and the third data table.

8. A controller, characterized in that: The method comprises a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the method for determining the remaining power as described in any one of claims 1 to 6 are implemented.

9. A battery management system, characterized in that: include: A controller as claimed in claim 8.

10. A readable storage medium, characterized in that: The readable storage medium stores a program or an instruction, and when the program or the instruction is executed by the processor, the steps of the method for determining the remaining power according to any one of claims 1 to 6 are implemented.

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