Silicon battery discharge terminal voltage compensation method, device, equipment and storage medium

Abstract

The present application discloses a method, device, equipment and storage medium for compensating the discharge terminal voltage of a silicon battery, which belongs to the field of batteries. The method includes determining the initial discharge terminal voltage corresponding to the current discharge current rate and the current temperature of the silicon battery; obtaining the discharge terminal voltage compensation table corresponding to the silicon battery at the current discharge current rate, the discharge terminal voltage compensation table is used to characterize the mapping relationship between different temperatures, different cycle periods and the discharge terminal voltage compensation coefficient; determining the discharge terminal voltage compensation coefficient corresponding to the current temperature and the current cycle period of the silicon battery from the discharge terminal voltage compensation table; obtaining the first estimated full charge capacity based on the discharge terminal voltage compensation coefficient and the initial discharge terminal voltage. The present application aims to solve the technical problem of reduced accuracy of full charge capacity caused by deviation of the discharge terminal voltage of silicon batteries in the prior art.

Description

Technical Field

[0001] The present application belongs to the field of batteries, and specifically relates to a method, device, equipment and storage medium for compensating the voltage at the end of discharge of a silicon battery. Background Art

[0002] In the prior art, the change in discharge terminal voltage under the OCV (Open Circuit Voltage) curve of the silicon negative electrode material during the cycle process is more obvious than that of the graphite negative electrode, that is, there is an offset in the discharge terminal voltage change compared with the graphite negative electrode. The offset discharge terminal voltage will cause the update accuracy of the battery's full charge capacity (FCC) to decrease. Summary of the invention

[0003] Purpose of the invention: This application develops a silicon battery discharge terminal voltage compensation method, device, equipment and storage medium, aiming to solve the technical problem of reduced full charge capacity accuracy caused by silicon battery discharge terminal voltage deviation in the prior art.

[0004] Technical solution: In a first aspect, an embodiment of the present application provides a silicon battery discharge terminal voltage compensation method, comprising:

[0005] Determine the initial discharge terminal voltage corresponding to the current discharge current rate and current temperature of the silicon battery;

[0006] Obtain a discharge terminal voltage compensation table corresponding to the silicon battery at the current discharge current rate, where the discharge terminal voltage compensation table is used to characterize the mapping relationship between different temperatures, different cycle periods and the discharge terminal voltage compensation coefficient;

[0007] Determine the discharge terminal voltage compensation coefficient corresponding to the current temperature and the current cycle period of the silicon battery from the discharge terminal voltage compensation table;

[0008] Based on the discharge end voltage compensation coefficient and the initial discharge end voltage, a first estimated full charge capacity is obtained.

[0009] In some embodiments, determining the initial discharge terminal voltage corresponding to the current discharge current rate and the current temperature of the silicon battery includes:

[0010] Obtaining an initial discharge terminal voltage reference table of a silicon battery, where the initial discharge terminal voltage reference table is used to characterize the mapping relationship between different temperatures, different discharge current rates and initial discharge terminal voltages;

[0011] The initial discharge terminal voltage corresponding to the current discharge current rate and the current temperature of the silicon battery is determined from the initial discharge terminal voltage reference table.

[0012] In some embodiments, the initial discharge end voltage reference table is constructed by the following steps:

[0013] Perform charge-discharge cycle tests on multiple sample silicon batteries to determine the initial discharge terminal voltage corresponding to different temperatures and different discharge current rates at the beginning of the charge-discharge cycle test;

[0014] Based on the initial discharge terminal voltages corresponding to different temperatures and different discharge current rates at the beginning of the charge and discharge cycle test, an initial discharge terminal voltage reference table is determined.

[0015] In some embodiments, the end-of-discharge voltage compensation table is constructed by the following steps:

[0016] Perform charge and discharge cycle tests on multiple sample silicon batteries to determine the first discharge terminal voltage corresponding to each cycle at different temperatures and different discharge current rates;

[0017] The difference between the first discharge terminal voltage corresponding to each cycle at different temperatures and different discharge current rates and the initial discharge terminal voltage at the corresponding temperature and discharge current rate at the beginning of the charge and discharge cycle test is determined as the deviation corresponding to each cycle;

[0018] The quotient of the deviation corresponding to each cycle period and the initial discharge terminal voltage at the corresponding temperature and the corresponding discharge current rate at the beginning of the charge and discharge cycle test is determined as the discharge terminal voltage compensation coefficient corresponding to each cycle period;

[0019] Based on the discharge terminal voltage compensation coefficient corresponding to each cycle period and different temperatures, a discharge terminal voltage compensation table corresponding to each discharge current rate is constructed.

[0020] In some embodiments, obtaining a first estimated full charge capacity based on a discharge end voltage compensation coefficient and an initial discharge end voltage includes:

[0021] Based on the discharge end voltage compensation coefficient and the initial discharge end voltage, a second discharge end voltage is obtained;

[0022] Based on the second end of discharge voltage, a first estimated full charge capacity is determined.

[0023] In some embodiments, obtaining a second discharge end voltage based on a discharge end voltage compensation coefficient and an initial discharge end voltage includes:

[0024] The corresponding compensation amount is obtained by multiplying the discharge end voltage compensation coefficient by the initial discharge end voltage;

[0025] The sum of the compensation amount and the corresponding initial discharge end voltage is determined as the second discharge end voltage.

[0026] In some embodiments, determining a first estimated full charge capacity based on the second end-of-discharge voltage includes:

[0027] Determine the current estimated full charge capacity;

[0028] Integrate the current and time of the silicon battery being discharged from a fully charged state to a second discharge terminal voltage corresponding to a current cycle and a current temperature to obtain an integral result;

[0029] Based on the current estimated full charge capacity, the discharge full charge capacity update point, and the integration result, a first estimated full charge capacity is determined.

[0030] In a second aspect, an embodiment of the present application provides a silicon battery discharge terminal voltage compensation device, comprising:

[0031] The first processing module is used to determine the initial discharge terminal voltage corresponding to the current discharge current rate and the current temperature of the silicon battery;

[0032] The second processing module is used to obtain a discharge terminal voltage compensation table corresponding to the silicon battery at the current discharge current rate, where the discharge terminal voltage compensation table is used to characterize the mapping relationship between different temperatures, different cycle periods and the discharge terminal voltage compensation coefficient;

[0033] A third processing module is used to determine a discharge terminal voltage compensation coefficient corresponding to the current temperature and the current cycle of the silicon battery from a discharge terminal voltage compensation table;

[0034] The fourth processing module is used to obtain a first estimated full charge capacity based on the discharge end voltage compensation coefficient and the initial discharge end voltage.

[0035] In a third aspect, an embodiment of the present application further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned silicon battery discharge terminal voltage compensation method when executing the computer program.

[0036] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of the above-mentioned silicon battery discharge terminal voltage compensation method are implemented.

[0037] Beneficial effect: The embodiment of the present application provides a method for compensating the discharge terminal voltage of a silicon battery. In actual use, the corresponding initial discharge terminal voltage is determined based on the current discharge current rate and the current temperature of the silicon battery, and the corresponding discharge terminal voltage compensation coefficient is determined in combination with the number of cycle cycles. Based on the discharge terminal voltage compensation coefficient and the initial discharge terminal voltage, a first estimated full charge capacity is obtained, and the obtained first estimated full charge capacity is the updated full charge capacity. The obtained first estimated full charge capacity solves the technical problem of the decrease in the accuracy of the full charge capacity caused by the discharge terminal voltage offset of the silicon battery. That is, the present application obtains the first estimated full charge capacity by intelligently compensating the discharge terminal voltage according to the characteristics of the silicon battery (the deeper the cycle aging degree, the lower the update accuracy of the obtained full charge capacity), so as to improve the update accuracy of the current full charge capacity of the silicon battery without adding peripheral circuits. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0039] Figure 1 The overall flow chart of the silicon battery discharge terminal voltage compensation method provided in the embodiment of the present application;

[0040] Figure 2 The steps for constructing the initial discharge terminal voltage reference table provided in the embodiment of the present application;

[0041] Figure 3 The steps for constructing the discharge end voltage compensation table provided in the embodiment of the present application;

[0042] Figure 4 An example diagram of the OCV-SOC curve provided in the embodiment of the present application;

[0043] Figure 5 A specific flow chart of the silicon battery discharge terminal voltage compensation method provided in the embodiment of the present application;

[0044] Figure 6 A schematic diagram of the structure of a silicon battery discharge terminal voltage compensation device provided in an embodiment of the present application;

[0045] Figure 7 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0047] It should be understood that although the terms first, second, etc. may be used herein to describe various components, these components should not be limited by these terms. These terms are used to distinguish one component from another component. Therefore, the first component discussed below can be referred to as the second component without departing from the teachings of the concepts of the present application. As used herein, the term "and / or" includes any one of the associated listed items and all combinations of one or more.

[0048] Those skilled in the art will appreciate that the drawings are only schematic diagrams of example embodiments and may not be to scale. The modules or processes in the drawings are not necessarily required to implement the present application and therefore cannot be used to limit the scope of protection of the present application.

[0049] Si (silicon) negative electrode materials are widely considered to be promising materials for the next generation of lithium-ion batteries because of their relatively high theoretical capacity, that is, more lithium ions can be stored per gram of negative electrode material. In addition, Si negative electrode materials also have a smaller lithium deintercalation potential than traditional graphite negative electrode materials, which means that lithium ions can more easily enter and exit Si negative electrode materials during charging and discharging. Another important factor is low cost. Compared with other candidate materials, such as lithium cobalt oxide, silicon negative electrode materials are more abundant and cheaper, so they have lower production costs. However, the change in the discharge end voltage under the OCV curve of Si negative electrode materials during the cycle process is more obvious than that of graphite negative electrode. Therefore, the existing algorithm for estimating capacity is difficult to apply to Si negative electrode batteries, and it is impossible to accurately estimate the current full charge capacity of the battery. This is reflected in the fact that as the degree of cycle aging deepens, the discharge end voltage will deviate, making it impossible to accurately estimate the current full charge capacity of the battery, resulting in a decrease in the update accuracy of the full charge capacity of the battery.

[0050] In view of this, an embodiment of the present application provides a silicon battery discharge terminal voltage compensation method, which determines the corresponding initial discharge terminal voltage based on the current discharge current rate and the current temperature of the silicon battery, and then determines the corresponding discharge terminal voltage compensation coefficient in combination with the number of cycle periods. The first estimated full charge capacity is obtained through the discharge terminal voltage compensation coefficient and the initial discharge terminal voltage, so as to improve the problem that the offset discharge terminal voltage will cause the update accuracy of the battery full charge capacity to decrease, thereby solving at least part of the above-mentioned technical problems.

[0051] See also Figure 1 , Figure 1The overall process of a silicon battery voltage discharge terminal voltage compensation method provided by an embodiment of the present application is illustrated. The method comprises the following steps:

[0052] Step 101: Determine the initial discharge terminal voltage corresponding to the current discharge current rate and the current temperature of the silicon battery.

[0053] Exemplarily, step 101 may be implemented in the following manner:

[0054] Obtain an initial discharge terminal voltage reference table for the silicon battery, which is used to characterize the mapping relationship between different temperatures, different discharge current rates and initial discharge terminal voltages; determine the initial discharge terminal voltage corresponding to the current discharge current rate and current temperature of the silicon battery from the initial discharge terminal voltage reference table.

[0055] In some embodiments, see Figure 2 , Figure 2 The steps for constructing the initial discharge terminal voltage reference table provided in the embodiment of the present application are illustrated. The initial discharge terminal voltage reference table can be constructed by the following steps:

[0056] Step 201: Perform a charge-discharge cycle test on a plurality of sample silicon batteries to determine the initial discharge terminal voltage corresponding to different temperatures and different discharge current rates at the beginning of the charge-discharge cycle test.

[0057] Specifically, assuming that the number of different temperature settings for the discharge end voltage is m and the number of different discharge current ratio settings is n, m×n initial discharge end voltages can be obtained based on m temperatures and n discharge current ratios.

[0058] It should be noted that the sample silicon battery is a silicon battery that has not undergone a discharge process. The temperature is the charging temperature of the battery, and the charging temperature of the battery is between 15°C and 45°C. Exemplarily, the temperature can be any one of 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, or any two of the range values. The discharge current rate is between 0.2C and 1.2C. Exemplarily, the discharge current rate can be any one of 0.2C, 0.3C, 0.4C, 0.5C, 0.6C, 0.7C, 0.8C, 0.9C, 1C, 1.1C, or 1.2C, or any two of the range values.

[0059] Step 202: Determine an initial discharge terminal voltage reference table based on the initial discharge terminal voltages corresponding to different temperatures and different discharge current rates at the beginning of the charge and discharge cycle test.

[0060] Specifically, assuming that the number of different temperature settings is m, and the number of different discharge current rate settings is n, based on the m temperatures and n discharge current rates, m×n corresponding initial discharge terminal voltages can be obtained, and the m×n corresponding initial discharge terminal voltages are sorted into a table to form an initial discharge terminal voltage reference table that characterizes the mapping relationship between different temperatures, different discharge current rates and initial discharge terminal voltages.

[0061] Please refer to Table 1, which is an example of the initial discharge terminal voltage reference table. Assuming the cycle period is 0-100 cycles, the temperature is 25°C, and the discharge terminal voltage at 0.5C discharge current rate is 3570mV as a benchmark, the corresponding initial discharge terminal voltage data is obtained based on the data of Si anode fresh batteries (Si anode fresh batteries are silicon batteries that have not undergone a discharge process) under different environments.

[0062] Table 1: Example of reference table for initial discharge end voltage

[0063]

[0064] In Table 1, Crate represents the discharge current rate, and the “-” in front of the discharge current rate represents the discharge state; Temp represents the charging temperature of the battery.

[0065] Through the above scheme, the current discharge current rate and current temperature of the silicon battery with known parameters are compared with the initial discharge terminal voltage reference table, and the initial discharge terminal voltage corresponding to the current discharge current rate and current temperature in the initial discharge terminal voltage reference table is selected to prepare for the subsequent calculation of the full charge capacity.

[0066] Step 102: Obtain a discharge terminal voltage compensation table corresponding to the silicon battery at the current discharge current rate, where the discharge terminal voltage compensation table is used to characterize the mapping relationship between different temperatures, different cycle periods and the discharge terminal voltage compensation coefficient.

[0067] In some embodiments, see Figure 3 , Figure 3 The steps for constructing the discharge end voltage compensation table provided in the embodiment of the present application are illustrated. The discharge end voltage compensation table is constructed by the following steps:

[0068] Step 301: Perform charge-discharge cycle tests on a plurality of sample silicon batteries to determine a first discharge terminal voltage corresponding to each cycle at different temperatures and different discharge current rates.

[0069] See also Figure 4 , Figure 4 An example diagram of an OCV-SOC curve provided in an embodiment of the present application is illustrated, with the horizontal axis representing SOC and the vertical axis representing OCV. Figure 4Curve a is the OCV-SOC curve of the silicon battery that has not undergone the discharge process, curve b is the OCV-SOC curve of the silicon battery after 400 cycles, curve c is the OCV-SOC curve of the silicon battery after 600 cycles, curve d is the OCV-SOC curve of the silicon battery after 800 cycles, and curve e is the OCV-SOC curve of the silicon battery after 1000 cycles. It should be noted that it is known that the degree of aging of the battery increases after continuous cycling. Through the OCV-SOC curve, it can be clearly observed that as the number of cycles increases, the discharge end voltage point shifts compared to the initial discharge end voltage point. Figure 4 As shown, point B represents the point on the OCV-SOC curve corresponding to the discharge end voltage after 1000 cycles, and point A represents the point on the OCV-SOC curve corresponding to the initial discharge end voltage. After 1000 cycles, point A shifts to point B.

[0070] Regarding the determination of the cycle period, a sample silicon battery is taken for charge and discharge cycle test. When the offset of the discharge end voltage point in the OCV-SOC curve of this sample silicon battery exceeds the accuracy range, the current cycle number is recorded as the number of one cycle period. In order to make the cycle period range more accurate, multiple sample silicon batteries can be taken for charge and discharge cycle test. The same method is used to obtain the cycle number of multiple cycles. The average of the cycle number of multiple cycles is taken as the cycle number of a single cycle required for the full charge capacity calculation of the same battery. For example, sample silicon battery a is subjected to charge and discharge cycle test. When the cycle is 199 cycles (battery charge and discharge cycle), the offset of the discharge end voltage point in the OCV-SOC curve of sample silicon battery a exceeds the accuracy range. 199 cycles are recorded as the cycle number of the cycle period. Sample silicon battery b is subjected to charge and discharge cycle test. When the cycle is 201 cycles, the offset of the discharge end voltage point in the OCV-SOC curve of sample silicon battery b exceeds the accuracy range. 201 cycles are recorded as the cycle number of the cycle period. Then the cycle number of the cycle period of this type of battery is determined to be 200 cycles.

[0071] Wherein, assuming that the number of cycles of a cycle is 100 cycles, the cycle cycles of a sample silicon battery for charge and discharge cycle test are 0-100 cycles, 100-200 cycles, 200-300 cycles, 300-400 cycles, and 400-500 cycles, respectively. Step 301 is to determine the first discharge terminal voltage corresponding to different temperatures and different discharge current rates when the sample silicon battery cycles 0-100 cycles, the first discharge terminal voltage corresponding to different temperatures and different discharge current rates when the sample silicon battery cycles 100-200 cycles, the first discharge terminal voltage corresponding to different temperatures and different discharge current rates when the sample silicon battery cycles 200-300 cycles, the first discharge terminal voltage corresponding to different temperatures and different discharge current rates when the sample silicon battery cycles 300-400 cycles, and the first discharge terminal voltage corresponding to different temperatures and different discharge current rates when the sample silicon battery cycles 400-500 cycles.

[0072] Step 302: Determine the difference between the first discharge terminal voltage corresponding to each cycle at different temperatures and different discharge current rates and the initial discharge terminal voltage at the corresponding temperature and discharge current rate at the beginning of the charge and discharge cycle test as the deviation corresponding to each cycle.

[0073] It should be noted that, assuming that when the silicon battery cycles 0-100 cycles, the first discharge terminal voltage is 3600mV at a temperature of 25°C and a discharge current rate of 0.5C; from the initial discharge terminal voltage reference table, the corresponding initial discharge terminal voltage is 3580mV at a temperature of 25°C and a discharge current rate of 0.5C, then the deviation corresponding to the cycle period of 0-100 cycles is 20 mV. Based on this method, the deviation corresponding to other cycle periods can be obtained.

[0074] Step 303: Determine the quotient of the deviation corresponding to each cycle and the initial discharge terminal voltage at the corresponding temperature and the corresponding discharge current rate at the beginning of the charge and discharge cycle test as the discharge terminal voltage compensation coefficient corresponding to each cycle.

[0075] It should be noted that, assuming that when the silicon battery cycles 0-100 cycles, the first discharge terminal voltage is 3600mV at a temperature of 25°C and a discharge current rate of 0.5C; the initial discharge terminal voltage is 3580mV at a temperature of 25°C and a discharge current rate of 0.5C, and the deviation corresponding to this cycle of 0-100 cycles is 20mV. The quotient of the deviation 20mV and the initial discharge terminal voltage 3580mV at a temperature of 25°C and a discharge current rate of 0.5C is determined as the discharge terminal voltage compensation coefficient corresponding to the cycle of 0-100 cycles. Based on this method, the discharge terminal voltage compensation coefficient corresponding to each cycle can be obtained.

[0076] Step 304: constructing a discharge end voltage compensation table corresponding to each discharge current ratio based on the discharge end voltage compensation coefficient corresponding to each cycle period and different temperatures.

[0077] It should be noted that, for the number of designed discharge current ratios, a corresponding discharge end voltage compensation table is constructed based on the discharge end voltage compensation coefficient corresponding to each cycle period and different temperatures.

[0078] Step 103: Determine the discharge terminal voltage compensation coefficient corresponding to the current temperature and the current cycle period of the silicon battery from the discharge terminal voltage compensation table.

[0079] Specifically, determine the current discharge current rate, find the discharge terminal voltage compensation table corresponding to the current discharge current rate, and then determine the discharge terminal voltage compensation coefficient corresponding to the current temperature and the current cycle of the silicon battery from the discharge terminal voltage compensation table. For example, assuming that the current discharge current rate is 0.5C, the current temperature is 25°C, and the current cycle is 0-100 cycles; find the discharge terminal voltage compensation table corresponding to the discharge current rate of 0.5C, and find the discharge terminal voltage compensation coefficient corresponding to the temperature of 25°C and the cycle of 0-100 cycles in this discharge terminal voltage compensation table.

[0080] It should be noted that in this embodiment, the compensation coefficient within the same cycle period can be regarded as a constant value. For example, if the offset is 10mV at 200 cycles, 100 cycles are regarded as an offset of 5mV. That is, when constructing the discharge end voltage compensation table, the discharge end voltage compensation coefficient in the discharge end voltage compensation table is the discharge end voltage compensation coefficient corresponding to the larger threshold in each cycle period.

[0081] Step 104: Obtain a first estimated full charge capacity based on the discharge end voltage compensation coefficient and the initial discharge end voltage.

[0082] Specifically, the discharge end voltage compensation coefficient corresponding to the current discharge current rate, the current temperature, and the current cycle period obtained in step 103 is combined with the initial discharge end voltage corresponding to the current discharge current rate and the current temperature in step 101, and the full charge capacity is calculated using the CEDV algorithm or the impedance tracking algorithm to obtain the first estimated full charge capacity.

[0083] In some embodiments, the specific steps of obtaining the first estimated full charge capacity based on the discharge end voltage compensation coefficient and the initial discharge end voltage are as follows:

[0084] Step 401: obtaining a second discharge end voltage based on a discharge end voltage compensation coefficient and an initial discharge end voltage.

[0085] In particular, step 401 is to multiply the discharge end voltage compensation coefficient by the initial discharge end voltage to obtain a corresponding compensation amount, and to determine the sum of the compensation amount and the corresponding initial discharge end voltage as the second discharge end voltage.

[0086] Specifically, step 401 is to multiply the discharge terminal voltage compensation coefficient corresponding to the current discharge current rate, current temperature, and current cycle period obtained in step 103 by the initial discharge terminal voltage corresponding to the current discharge current rate and current temperature in step 101 to obtain the actual compensation amount required. Then, the actual compensation amount required is summed with the initial discharge terminal voltage corresponding to the current discharge current rate and current temperature in step 101 to obtain the second discharge terminal voltage.

[0087] Step 402: Determine a first estimated full charge capacity based on the second end-of-discharge voltage.

[0088] Among them, step 402 is specifically to determine the current estimated full charge capacity; integrate the current and time of the silicon battery discharging from the fully charged state to the second discharge terminal voltage corresponding to the current cycle period and the current temperature to obtain the integration result; based on the current estimated full charge capacity, the discharge full charge capacity update point, and the integration result, determine the first estimated full charge capacity.

[0089] Specifically, step 402 satisfies the following formula:

[0090] (1);

[0091] In formula (1), is the first estimated full charge capacity, is the second discharge end voltage, is the current estimated full charge capacity, Update point for discharge to full charge capacity.

[0092] Exemplarily, based on the settings in the aforementioned Table 1, an example of the discharge end voltage compensation table corresponding to the 0.5C discharge current rate discharge is shown in Table 2.

[0093] Table 2: Discharge end voltage compensation table corresponding to 0.5C discharge current rate discharge

[0094]

[0095] In Table 2, Cycle represents the number of cycles.

[0096] If the current number of cycles is 200, and EDV at 25°C is 3570+3570×0.016=3627mV, then the current full charge capacity (current estimated full charge capacity) is the integral of the current and time from full charge and discharge to 3627mV plus 7%×the current estimated full charge capacity to obtain the new estimated full charge capacity (first estimated full charge capacity).

[0097] For example, the battery used in the electronic device usually has a fuel gauge chip with a CEDV algorithm. During the use of the battery, the fuel gauge chip can evaluate the full charge capacity based on the CEDV algorithm. In addition to the fuel gauge chip with the CEDV algorithm, there is also a fuel gauge chip with an impedance tracking algorithm. During the use of the battery, the fuel gauge chip can evaluate the full charge capacity based on the impedance tracking algorithm.

[0098] Among them, the fuel gauge is responsible for estimating the battery capacity. Its basic functions are to monitor the voltage, charge and discharge current and battery temperature, and estimate the battery state of charge (SOC) and the battery's full charge capacity.

[0099] The CEDV (Compensated End of Discharge Voltage) algorithm is a method of calculating the amount of electricity based on Coulomb integration. It evaluates the battery capacity by obtaining data from charging and discharging the battery. When using the CEDV algorithm, during the battery discharge process, it is usually necessary to pay attention to the discharge end voltage corresponding to 7% of the battery cell capacity. The discharge end voltage at 7% of the battery cell capacity will affect the accuracy of the estimated full charge capacity.

[0100] In some embodiments, see Figure 5 , Figure 5 The specific process of the silicon battery discharge terminal voltage compensation method is illustrated. In this embodiment, the initial discharge terminal voltage of the silicon battery under different environments is initially collected, and the discharge terminal voltage compensation coefficient corresponding to the current environment is obtained through calculation. The current estimated full charge capacity is calculated according to the measured value, and the corresponding discharge terminal voltage compensation coefficient is intelligently called according to the actual use based on the estimated full charge capacity and the corresponding discharge terminal voltage compensation coefficient for compensation, that is, the first estimated full charge capacity in step 104 is obtained.

[0101] It can be understood that the silicon battery discharge terminal voltage compensation method of the embodiment of the present application determines the corresponding initial discharge terminal voltage based on the current discharge current rate and current temperature of the silicon battery in actual use, and then determines the corresponding discharge terminal voltage compensation coefficient in combination with the number of cycle cycles. Based on the discharge terminal voltage compensation coefficient and the initial discharge terminal voltage, a first estimated full charge capacity is obtained, and the obtained first estimated full charge capacity is the updated full charge capacity. The obtained first estimated full charge capacity solves the technical problem of the decrease in the accuracy of the full charge capacity caused by the discharge terminal voltage offset of the silicon battery. That is, the present application obtains the first estimated full charge capacity by intelligently compensating the discharge terminal voltage according to the characteristics of the silicon battery (the deeper the cycle aging degree, the lower the update accuracy of the obtained full charge capacity), so as to improve the update accuracy of the current full charge capacity of the silicon battery without adding peripheral circuits.

[0102] Accordingly, see Figure 6 , Figure 6 The structure of a silicon battery discharge terminal voltage compensation device in an embodiment of the present application is illustrated. A silicon battery discharge terminal voltage compensation device provided in an embodiment of the present application includes a first processing module, a second processing module, a third processing module, and a fourth processing module, wherein:

[0103] The first processing module is used to determine the initial discharge terminal voltage corresponding to the current discharge current rate and the current temperature of the silicon battery.

[0104] The second processing module is used to obtain a discharge terminal voltage compensation table corresponding to the silicon battery at the current discharge current rate, and the discharge terminal voltage compensation table is used to characterize the mapping relationship between different temperatures, different cycle periods and discharge terminal voltage compensation coefficients.

[0105] The third processing module is used to determine the discharge terminal voltage compensation coefficient corresponding to the current temperature and the current cycle period of the silicon battery from the discharge terminal voltage compensation table.

[0106] The fourth processing module is used to obtain a first estimated full charge capacity based on the discharge end voltage compensation coefficient and the initial discharge end voltage.

[0107] In some embodiments, the first processing module determines the initial discharge terminal voltage corresponding to the current discharge current rate and the current temperature of the silicon battery, including the following steps:

[0108] Obtaining an initial discharge terminal voltage reference table of a silicon battery, where the initial discharge terminal voltage reference table is used to characterize the mapping relationship between different temperatures, different discharge current rates and initial discharge terminal voltages;

[0109] The initial discharge terminal voltage corresponding to the current discharge current rate and the current temperature of the silicon battery is determined from the initial discharge terminal voltage reference table.

[0110] In some embodiments, the initial discharge end voltage reference table is constructed by the following steps:

[0111] Perform charge-discharge cycle tests on multiple sample silicon batteries to determine the initial discharge terminal voltage corresponding to different temperatures and different discharge current rates at the beginning of the charge-discharge cycle test;

[0112] Based on the initial discharge terminal voltages corresponding to different temperatures and different discharge current rates at the beginning of the charge and discharge cycle test, an initial discharge terminal voltage reference table is determined.

[0113] In some embodiments, the end-of-discharge voltage compensation table is constructed by the following steps:

[0114] Perform charge and discharge cycle tests on multiple sample silicon batteries to determine the first discharge terminal voltage corresponding to each cycle at different temperatures and different discharge current rates;

[0115] The difference between the first discharge terminal voltage corresponding to each cycle at different temperatures and different discharge current rates and the initial discharge terminal voltage at the corresponding temperature and discharge current rate at the beginning of the charge and discharge cycle test is determined as the deviation corresponding to each cycle;

[0116] The quotient of the deviation corresponding to each cycle period and the initial discharge terminal voltage at the corresponding temperature and the corresponding discharge current rate at the beginning of the charge and discharge cycle test is determined as the discharge terminal voltage compensation coefficient corresponding to each cycle period;

[0117] Based on the discharge terminal voltage compensation coefficient corresponding to each cycle period and different temperatures, a discharge terminal voltage compensation table corresponding to each discharge current rate is constructed.

[0118] In some embodiments, the fourth processing module obtains a first estimated full charge capacity based on the discharge end voltage compensation coefficient and the initial discharge end voltage, comprising the following steps:

[0119] Based on the discharge end voltage compensation coefficient and the initial discharge end voltage, a second discharge end voltage is obtained;

[0120] Based on the second end of discharge voltage, a first estimated full charge capacity is determined.

[0121] In some embodiments, the fourth processing module obtains the second discharge end voltage based on the discharge end voltage compensation coefficient and the initial discharge end voltage, comprising the following steps:

[0122] The corresponding compensation amount is obtained by multiplying the discharge end voltage compensation coefficient by the initial discharge end voltage;

[0123] The sum of the compensation amount and the corresponding initial discharge end voltage is determined as the second discharge end voltage.

[0124] In some embodiments, the fourth processing module determines the first estimated full charge capacity based on the second end-of-discharge voltage, comprising the following steps:

[0125] Determine the current estimated full charge capacity;

[0126] Integrate the current and time of the silicon battery being discharged from a fully charged state to a second discharge terminal voltage corresponding to a current cycle and a current temperature to obtain an integral result;

[0127] Based on the current estimated full charge capacity, the discharge full charge capacity update point, and the integration result, a first estimated full charge capacity is determined.

[0128] It can be understood that the silicon battery discharge terminal voltage compensation device of the embodiment of the present application, when actually used, determines the corresponding initial discharge terminal voltage based on the current discharge current rate and current temperature of the silicon battery through the first processing module, and then determines the corresponding discharge terminal voltage compensation coefficient through the third processing module in combination with the number of cycle cycles; the fourth processing module obtains the first estimated full charge capacity based on the discharge terminal voltage compensation coefficient and the initial discharge terminal voltage, and the obtained first estimated full charge capacity is the updated full charge capacity. The obtained first estimated full charge capacity solves the technical problem of the decrease in the accuracy of the full charge capacity caused by the discharge terminal voltage offset of the silicon battery. That is, the present application obtains the first estimated full charge capacity by intelligently compensating the discharge terminal voltage according to the characteristics of the silicon battery (the deeper the cycle aging degree, the lower the update accuracy of the obtained full charge capacity), so as to improve the update accuracy of the current full charge capacity of the silicon battery without adding peripheral circuits.

[0129] Accordingly, the present application also provides an electronic device, see Figure 7 , Figure 7 The structure of the electronic device of the embodiment of the present application is illustrated. The electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the silicon battery discharge terminal voltage compensation method when executing the computer program.

[0130] The electronic device of the embodiment of the present application may be a mopping machine, an electric vehicle, an energy storage system, a testing device, etc. The embodiment of the present application does not impose any special restrictions on the above electronic devices. It is understandable that since the silicon battery discharge terminal voltage compensation method is described in detail above, it will not be repeated here.

[0131] It is understandable that the electronic device of the embodiment of the present application, in the actual use process, has always used the silicon battery discharge terminal voltage compensation method to estimate the first estimated full charge capacity, that is, the update accuracy of the silicon battery full charge capacity is high, so that the electronic device has a longer service life. Accordingly, the embodiment of the present application also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by the processor, the steps of the above-mentioned silicon battery discharge terminal voltage compensation method are implemented. Since the silicon battery discharge terminal voltage compensation method is described in detail above, it will not be repeated here.

[0132] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0133] The above is a detailed introduction to the silicon battery discharge terminal voltage compensation method, device, equipment and storage medium provided in the embodiments of the present application, and the principles and implementation methods of the present application are explained by using specific examples. The description of the above embodiments is only used to help understand the technical solution and its core idea of ​​the present application; ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present application.

Claims

1. A method for compensating the voltage at the end of discharge of a silicon battery, characterized in that: include: Determine the initial discharge terminal voltage corresponding to the current discharge current rate and current temperature of the silicon battery; Obtaining a discharge terminal voltage compensation table corresponding to the silicon battery at the current discharge current rate, wherein the discharge terminal voltage compensation table is used to characterize a mapping relationship between different temperatures, different cycle periods and discharge terminal voltage compensation coefficients; Determining the discharge terminal voltage compensation coefficient corresponding to the current temperature and the current cycle of the silicon battery from the discharge terminal voltage compensation table; Obtaining a first estimated full charge capacity based on the discharge end voltage compensation coefficient and the initial discharge end voltage; The obtaining a first estimated full charge capacity based on the discharge end voltage compensation coefficient and the initial discharge end voltage includes: Based on the discharge end voltage compensation coefficient and the initial discharge end voltage, obtaining a second discharge end voltage; determining the first estimated full charge capacity based on the second discharge end voltage; The determining the first estimated full charge capacity based on the second discharge end voltage includes: Determine the current estimated full charge capacity; Integrate the current and time of the silicon battery being discharged from a fully charged state to the second discharge terminal voltage corresponding to the current cycle and the current temperature to obtain an integration result; The first estimated full charge capacity is determined based on the current estimated full charge capacity, the discharge full charge capacity update point, and the integration result.

2. A silicon battery discharge terminal voltage compensation method according to claim 1, characterized in that: The step of determining the initial discharge terminal voltage corresponding to the current discharge current rate and the current temperature of the silicon battery includes: Obtaining an initial discharge terminal voltage reference table of the silicon battery, wherein the initial discharge terminal voltage reference table is used to characterize a mapping relationship between different temperatures, different discharge current rates and the initial discharge terminal voltage; The initial discharge terminal voltage corresponding to the current discharge current rate and the current temperature of the silicon battery is determined from the initial discharge terminal voltage reference table.

3. A silicon battery discharge terminal voltage compensation method according to claim 2, characterized in that: The initial discharge terminal voltage reference table is constructed by the following steps: Performing a charge-discharge cycle test on a plurality of sample silicon batteries to determine the initial discharge terminal voltage corresponding to different temperatures and different discharge current rates at the beginning of the charge-discharge cycle test; The initial discharge terminal voltage reference table is determined based on the initial discharge terminal voltage corresponding to different temperatures and different discharge current rates at the beginning of the charge and discharge cycle test.

4. A silicon battery discharge terminal voltage compensation method according to claim 3, characterized in that: The discharge end voltage compensation table is constructed by the following steps: Performing charge and discharge cycle tests on a plurality of the sample silicon batteries to determine a first discharge terminal voltage corresponding to each cycle at different temperatures and different discharge current rates; Determine the difference between the first discharge terminal voltage corresponding to each cycle at different temperatures and different discharge current rates and the initial discharge terminal voltage at the corresponding temperature and discharge current rate at the beginning of the charge and discharge cycle test as the deviation corresponding to each cycle; Determine the quotient of the deviation corresponding to each cycle and the initial discharge terminal voltage at the corresponding temperature and the corresponding discharge current rate at the beginning of the charge-discharge cycle test as the discharge terminal voltage compensation coefficient corresponding to each cycle; Based on the discharge end voltage compensation coefficient corresponding to each of the cycle periods and different temperatures, the discharge end voltage compensation table corresponding to each of the discharge current ratios is constructed.

5. The method for compensating the voltage at the end of discharge of a silicon battery according to claim 1, characterized in that: The obtaining of a second discharge end voltage based on the discharge end voltage compensation coefficient and the initial discharge end voltage comprises: Multiplying the discharge end voltage compensation coefficient by the initial discharge end voltage to obtain a corresponding compensation amount; The sum of the compensation amount and the corresponding initial discharge end voltage is determined as the second discharge end voltage.

6. A silicon battery discharge terminal voltage compensation device, characterized in that: include: A first processing module, used to determine the initial discharge terminal voltage corresponding to the current discharge current rate and the current temperature of the silicon battery; A second processing module is used to obtain a discharge terminal voltage compensation table corresponding to the silicon battery at the current discharge current rate, wherein the discharge terminal voltage compensation table is used to characterize a mapping relationship between different temperatures, different cycle periods and discharge terminal voltage compensation coefficients; A third processing module, used to determine the discharge end voltage compensation coefficient corresponding to the current temperature and the current cycle of the silicon battery from the discharge end voltage compensation table; a fourth processing module, configured to obtain a first estimated full charge capacity based on the discharge end voltage compensation coefficient and the initial discharge end voltage; The obtaining a first estimated full charge capacity based on the discharge end voltage compensation coefficient and the initial discharge end voltage includes: Based on the discharge end voltage compensation coefficient and the initial discharge end voltage, obtaining a second discharge end voltage; determining the first estimated full charge capacity based on the second discharge end voltage; The determining the first estimated full charge capacity based on the second discharge end voltage includes: Determine the current estimated full charge capacity; Integrate the current and time of the silicon battery being discharged from a fully charged state to the second discharge terminal voltage corresponding to the current cycle and the current temperature to obtain an integration result; The first estimated full charge capacity is determined based on the current estimated full charge capacity, the discharge full charge capacity update point, and the integration result.

7. An electronic device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the silicon battery discharge terminal voltage compensation method according to any one of claims 1 to 5 when executing the computer program.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the silicon battery discharge terminal voltage compensation method described in any one of claims 1 to 5 are implemented.

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