CN117406096A - A voltage value updating method and device for SOC calibration point of lithium iron phosphate battery - Google Patents

Abstract

The invention discloses a voltage value updating method and a device of an SOC correction point of a lithium iron phosphate battery, which are characterized in that the maximum first voltage corresponding to each integral battery charge state variable is obtained based on the first voltage of each single core in the lithium iron phosphate battery, and the first differential pressure of the default voltage corresponding to each maximum first voltage and the integral battery charge state variable is calculated to obtain the maximum first differential pressure; when the maximum first differential pressure is determined to be larger than a preset differential pressure threshold value, calculating a second differential pressure of each maximum first voltage and the standby voltage corresponding to each integral battery charge state variable to obtain a maximum second differential pressure; when the maximum second differential pressure is not larger than the preset differential pressure threshold value, taking the maximum first voltage corresponding to each integral battery charge state variable as a default voltage; compared with the prior art, the technical scheme of the invention can realize the update of the voltage value of the SOC correction point of the lithium iron phosphate battery, and simultaneously avoid the problem of poor applicability of the correction point caused by inconsistent battery cells.

Description

A voltage value updating method and device for SOC calibration point of lithium iron phosphate battery

Technical field

The present invention relates to the technical field of battery management systems, and in particular to a method and device for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery.

Background technique

The SOC estimation of the power battery is one of the core functions of the battery management system. Accurate SOC estimation is important for ensuring the safe and reliable operation of the power battery, improving the efficient utilization of stored electric energy and power, optimizing energy management and safety management, and preventing overcharging of the power battery. It is of great significance to prevent over-discharge and ensure its long-life operation; however, power batteries have few measurable parameters, characteristic coupling, nonlinearity, strong time variability, etc., and the application of electric vehicles faces full working conditions and wide range of Temperature range and other requirements, high-precision and robust power battery state estimation faces great challenges. It has always been a difficult problem in industry technology research and a hot topic in international academic research; especially for lithium iron phosphate batteries, due to its OCV curve The platform nature brings great difficulty to the accurate estimation of SOC. Finding the point where SOC correction can be performed is particularly important to eliminate the SOC error accumulated during long-term operation in the platform period.

At present, there are two main methods for SOC error correction of lithium iron phosphate batteries: one is to perform OCV correction in the low SOC range, that is, the area with a large slope of the OCV curve; the other is to perform OCV correction based on the corresponding relationship between the voltage value and SOC at the charging end. , correct the SOC value, that is, within the correction range, how much it is charged and corrected to, it is corrected to 100% when it is full.

The conditions required by the first method are relatively harsh. The battery needs to be discharged to a lower SOC state and then left to stand for a long enough time. In actual vehicle applications, this condition is rarely met; the scenarios required by the second method In actual applications, it occurs more frequently, so it is more commonly used; however, because the correction method is mainly to set a set of fixed voltage and SOC corresponding points in the BMS, when the consistency of the cells in the battery pack is poor or the battery ages, This correspondence will lose accuracy, causing this method to be unable to eliminate errors well.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method and device for updating the voltage value of the SOC calibration point of the lithium iron phosphate battery, to realize the update of the voltage value of the SOC calibration point of the lithium iron phosphate battery, and at the same time to avoid the problems caused by inconsistent battery cells. The problem of poor applicability of calibration points.

In order to solve the above technical problems, the present invention provides a method for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery, which includes:

When it is determined that the lithium iron phosphate battery enters the charging state and the temperature of the lithium iron phosphate battery is greater than the preset temperature threshold, obtaining each integrated battery charge state variable within the preset integrated battery charge state variable range, the iron phosphate The first voltage of each single cell in the lithium battery, and based on the first voltage, obtain the maximum first voltage corresponding to the charge state variable of each integrated battery;

Select the default voltage corresponding to each integrated battery charge state variable, calculate the first voltage difference between each maximum first voltage and the corresponding default voltage, and obtain the maximum first voltage difference among all first voltage differences;

When it is determined that the maximum first voltage difference is greater than the preset voltage difference threshold, obtain the backup voltage corresponding to each integrated battery charge state variable, and calculate the second voltage difference between each maximum first voltage and the corresponding backup voltage, Obtain the maximum second pressure difference among all second pressure differences;

When it is determined that the maximum second voltage difference is not greater than the preset voltage difference threshold, the maximum first voltage corresponding to each integrated battery charge state variable is used as the maximum first voltage corresponding to each integrated battery charge state variable. the default voltage.

In a possible implementation, the first voltage of each single cell in the lithium iron phosphate battery is obtained for each integrated battery charge state variable within the preset integrated battery charge state variable range, and based on the The first voltage is described above to obtain the maximum first voltage corresponding to each integrated battery charge state variable, which specifically includes:

Obtain the default voltage sequence of the lithium iron phosphate battery, and simultaneously obtain the integrated battery charge state variable of the lithium iron phosphate battery;

Determine whether the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range. If not, obtain each unit in the lithium iron phosphate battery under the integrated battery charge state variable. Based on the first voltage of the single cell, the maximum first voltage corresponding to the integrated battery charge state variable is obtained based on the plurality of first voltages;

After obtaining the maximum first voltage corresponding to the integrated battery charge state variable, the default voltage sequence is shifted to the left, the first default voltage sequence variable in the default voltage sequence is deleted, and all The maximum first voltage is placed at the end of the default voltage sequence as the last default voltage sequence variable of the default voltage sequence;

Reacquire the current integrated battery charge state variable. When it is determined that there is a change between the current integrated battery charge state variable and the integrated battery charge state variable, use the current integrated battery charge state variable as the integrated battery charge state variable, and Re-determine whether the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range;

Until it is determined that the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range, and there is no change between the current integrated battery charge state variable and the integrated battery charge state variable, obtain Current default voltage sequence;

Based on the current default voltage sequence, the maximum first voltage corresponding to each integrated battery charge state variable is obtained.

In a possible implementation, before selecting the default voltage corresponding to each integrated battery charge state variable, the method further includes:

Select a plurality of first single cells, confirm that the first single cells are in an empty state, and place the plurality of first single cells in an environment at a first preset temperature for static processing Finally, the plurality of first single cells are charged respectively, and during the charging process, each first integrated battery charge state of each first single cell within the preset integrated battery charge state variable range is recorded. The voltage data corresponding to the variable;

All voltage data corresponding to each first integrated battery charge state variable are averaged to obtain average voltage data, and the average voltage data is used as each first integrated battery charge state variable at the first preset temperature. The corresponding first default voltage;

Select a plurality of second single cells, confirm that the second single cells are in an empty state, and place the plurality of second single cells in an environment at a second preset temperature for static processing Finally, the plurality of second single cells are charged respectively, and during the charging process, the charge state of each second integrated battery within the preset integrated battery charge state variable range is recorded. The voltage data corresponding to the variable;

All voltage data corresponding to each second integrated battery charge state variable are averaged to obtain average voltage data, and the average voltage data is used as each second integrated battery charge state variable at the second preset temperature. The corresponding second default voltage;

Select a plurality of third single cell cells, confirm that the third single cell cell is in an empty state, and place the plurality of third single cell cells in an environment at a second preset temperature for static processing Then, the plurality of third single cells are charged respectively, and during the charging process, the corresponding third integrated battery charge state variable of each third sample battery within the preset integrated battery charge state variable range is recorded. voltage data;

All voltage data corresponding to each third integrated battery charge state variable are averaged to obtain average voltage data, and the average voltage data is used as each third integrated battery charge state variable at the third preset temperature. Corresponding third default voltage.

The invention provides a method for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery, which also includes:

Obtain the first battery temperature corresponding to each integrated battery charge state variable within the preset integrated battery charge state variable range of the lithium iron phosphate battery, and obtain the first battery temperature corresponding to multiple integrated battery charge state variables.

In a possible implementation, selecting the default voltage corresponding to each integrated battery charge state variable also includes:

Obtain the first battery temperature corresponding to each integrated battery charge state variable to obtain a plurality of first battery temperatures, calculate an average of the plurality of first battery temperatures, and obtain an average first battery temperature;

According to the first battery temperature average, a preset temperature corresponding to each integrated battery charge state variable is determined, and based on the preset temperature, a default voltage corresponding to each integrated battery charge state variable is selected.

The invention provides a method for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery, which also includes:

When it is determined that the maximum second voltage difference is greater than the preset voltage difference threshold, the maximum first voltage corresponding to each integrated battery charge state variable is used as the maximum first voltage corresponding to each integrated battery charge state variable. Describe the backup voltage.

The invention provides a method for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery, which also includes:

When it is determined that the maximum first voltage difference is not greater than the preset voltage difference threshold, the maximum first voltage corresponding to each integrated battery charge state variable is used as the corresponding to each integrated battery charge state variable. Default voltage.

The invention also provides a voltage value updating device for SOC calibration point of lithium iron phosphate battery, including: a first voltage acquisition module, a first verification module, a second verification module and a first default voltage update module;

Wherein, the first voltage acquisition module is used to acquire each voltage within the preset integrated battery charge state variable range when it is determined that the lithium iron phosphate battery enters the charging state and the temperature of the lithium iron phosphate battery is greater than a preset temperature threshold. Under the integrated battery charge state variables, the first voltage of each single cell in the lithium iron phosphate battery, and based on the first voltage, obtain the maximum first voltage corresponding to each integrated battery charge state variable;

The first verification module is used to select the default voltage corresponding to each integrated battery charge state variable, calculate the first voltage difference between each maximum first voltage and the corresponding default voltage, and obtain all first voltage differences. The maximum first pressure difference in;

The second verification module is configured to obtain the backup voltage corresponding to each integrated battery charge state variable when it is determined that the maximum first voltage difference is greater than the preset voltage difference threshold, and calculate the relationship between each maximum first voltage and the corresponding The second voltage difference of the standby voltage is used to obtain the maximum second voltage difference among all second voltage differences;

The first default voltage update module is configured to, when determining that the maximum second voltage difference is not greater than the preset voltage difference threshold, use the maximum first voltage corresponding to each integrated battery charge state variable as The default voltage corresponding to each integrated battery charge state variable.

In a possible implementation, the first voltage acquisition module is used to acquire, for each integrated battery charge state variable within a preset integrated battery charge state variable range, each cell in the lithium iron phosphate battery. The first voltage of a single cell, and based on the first voltage, the maximum first voltage corresponding to each integrated battery charge state variable is obtained, specifically including:

Obtain the default voltage sequence of the lithium iron phosphate battery, and simultaneously obtain the integrated battery charge state variable of the lithium iron phosphate battery;

Determine whether the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range. If not, obtain each unit in the lithium iron phosphate battery under the integrated battery charge state variable. Based on the first voltage of the single cell, the maximum first voltage corresponding to the integrated battery charge state variable is obtained based on the plurality of first voltages;

After obtaining the maximum first voltage corresponding to the integrated battery charge state variable, the default voltage sequence is shifted to the left, the first default voltage sequence variable in the default voltage sequence is deleted, and all The maximum first voltage is placed at the end of the default voltage sequence as the last default voltage sequence variable of the default voltage sequence;

Reacquire the current integrated battery charge state variable. When it is determined that there is a change between the current integrated battery charge state variable and the integrated battery charge state variable, use the current integrated battery charge state variable as the integrated battery charge state variable, and Re-determine whether the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range;

Until it is determined that the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range, and there is no change between the current integrated battery charge state variable and the integrated battery charge state variable, obtain Current default voltage sequence;

Based on the current default voltage sequence, the maximum first voltage corresponding to each integrated battery charge state variable is obtained.

In a possible implementation, the first verification module, before selecting the default voltage corresponding to each integrated battery charge state variable, further includes:

Select a plurality of first single cells, confirm that the first single cells are in an empty state, and place the plurality of first single cells in an environment at a first preset temperature for static processing Finally, the plurality of first single cells are charged respectively, and during the charging process, each first integrated battery charge state of each first single cell within the preset integrated battery charge state variable range is recorded. The voltage data corresponding to the variable;

All voltage data corresponding to each first integrated battery charge state variable are averaged to obtain average voltage data, and the average voltage data is used as each first integrated battery charge state variable at the first preset temperature. The corresponding first default voltage;

Select a plurality of second single cells, confirm that the second single cells are in an empty state, and place the plurality of second single cells in an environment at a second preset temperature for static processing Finally, the plurality of second single cells are charged respectively, and during the charging process, the charge state of each second integrated battery within the preset integrated battery charge state variable range is recorded. The voltage data corresponding to the variable;

All voltage data corresponding to each second integrated battery charge state variable are averaged to obtain average voltage data, and the average voltage data is used as each second integrated battery charge state variable at the second preset temperature. The corresponding second default voltage;

Select a plurality of third single cell cells, confirm that the third single cell cell is in an empty state, and place the plurality of third single cell cells in an environment at a second preset temperature for static processing Then, the plurality of third single cells are charged respectively, and during the charging process, the corresponding third integrated battery charge state variable of each third sample battery within the preset integrated battery charge state variable range is recorded. voltage data;

All voltage data corresponding to each third integrated battery charge state variable are averaged to obtain average voltage data, and the average voltage data is used as each third integrated battery charge state variable at the third preset temperature. Corresponding third default voltage.

The invention provides a device for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery, further comprising: a first battery temperature acquisition module;

The first battery temperature acquisition module is used to obtain the first battery temperature corresponding to each integrated battery charge state variable of the lithium iron phosphate battery within the preset integrated battery charge state variable range, and obtain multiple integrated battery charge state variables. corresponding to the first battery temperature.

In a possible implementation, the first verification module is used to select the default voltage corresponding to each integrated battery charge state variable, and further includes:

Obtain the first battery temperature corresponding to each integrated battery charge state variable to obtain a plurality of first battery temperatures, calculate an average of the plurality of first battery temperatures, and obtain an average first battery temperature;

According to the first battery temperature average, a preset temperature corresponding to each integrated battery charge state variable is determined, and based on the preset temperature, a default voltage corresponding to each integrated battery charge state variable is selected.

The invention provides a voltage value updating device for the SOC calibration point of a lithium iron phosphate battery, further comprising: a backup voltage updating module;

The backup voltage update module is also configured to use the maximum first voltage corresponding to each integrated battery charge state variable as the maximum second voltage difference when it is determined that the maximum second voltage difference is greater than the preset voltage difference threshold. The backup voltage corresponding to each integrated battery charge state variable.

The invention provides a device for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery, further comprising: a second default voltage update module;

The second default voltage update module is configured to use the maximum first voltage corresponding to each integrated battery charge state variable as the maximum first voltage when it is determined that the maximum first voltage difference is not greater than a preset voltage difference threshold. The default voltage corresponding to each integrated battery charge state variable.

The present invention also provides a terminal device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, any of the above is implemented. A method for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery.

The present invention also provides a computer-readable storage medium. The computer-readable storage medium includes a stored computer program, wherein when the computer program is running, the device where the computer-readable storage medium is located is controlled to execute any one of the above steps. The method for updating the voltage value of the SOC calibration point of the lithium iron phosphate battery described in the item.

The embodiment of the present invention is a method and device for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery. Compared with the existing technology, it has the following beneficial effects:

When it is determined that the lithium iron phosphate battery enters the charging state and the temperature of the lithium iron phosphate battery is greater than the preset temperature threshold, obtain each integrated battery charge state variable within the preset integrated battery charge state variable range. The first voltage of each single cell is obtained, and based on the first voltage, the maximum first voltage corresponding to the charge state variable of each integrated battery is obtained; the default voltage corresponding to the charge state variable of each integrated battery is selected, and each maximum first voltage is calculated. The first voltage difference between the voltage and the corresponding default voltage is obtained to obtain the maximum first voltage difference among all first voltage differences; when it is determined that the maximum first voltage difference is greater than the preset voltage difference threshold, the corresponding value of each integrated battery charge state variable is obtained of the backup voltage, calculate the second pressure difference between each maximum first voltage and the corresponding backup voltage, and obtain the maximum second pressure difference among all second pressure differences; after determining that the maximum second pressure difference is not greater than the preset pressure difference threshold When The voltage value can effectively solve the problems faced when the voltage value of the current calibration point is fixed, so that the accuracy of subsequent correction of the SOC error can be improved based on the updated voltage value.

Description of the drawings

Figure 1 is a schematic flow chart of an embodiment of a method for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery provided by the present invention;

Figure 2 is a schematic structural diagram of an embodiment of a device for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery provided by the present invention;

Figure 3 is a schematic diagram of the second table variable U16_ChgVvsSOC_Def according to an embodiment of the present invention;

Figure 4 is a schematic diagram of the temporary table variable U16_ChgVvsSOC_temp of the charging process according to an embodiment of the present invention;

Figure 5 is a schematic diagram of a default voltage sequence according to an embodiment of the present invention;

Figure 6 is a schematic diagram of default voltage sequence movement according to an embodiment of the present invention;

Figure 7 is a diagram illustrating a charging map according to an embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention.

Embodiment 1. Refer to Figure 1. Figure 1 is a flow chart of an embodiment of a method for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery provided by the present invention. As shown in Figure 1, the method includes steps 101- Step 104 is as follows:

Step 101: When it is determined that the lithium iron phosphate battery enters the charging state and the temperature of the lithium iron phosphate battery is greater than the preset temperature threshold, obtain each integrated battery charge state variable within the preset integrated battery charge state variable range. The first voltage of each single cell in the lithium iron phosphate battery is obtained, and based on the first voltage, the maximum first voltage corresponding to the charge state variable of each integrated battery is obtained.

In one embodiment, a first table variable U16_ChgVvsSOC_Upt is set inside the battery management system BMS program. The data type is uint16 and the size is 3×11. It is used to store the voltage points for battery charge state variable correction during actual operation. At the same time, the The variable table is also used to store new corrected voltage points obtained by subsequent program self-learning.

In one embodiment, a second table variable U16_ChgVvsSOC_Def is set inside the battery management system BMS program. The data type is uint16 and the size is 3×11. It is used to store the measured default relationship data. Each row represents a temperature point ( (0°C, 15°C, 25°C respectively), each column represents the voltage value corresponding to the SOC point (from 90% to 100%); as shown in Figure 3, Figure 3 is a schematic diagram of the second table variable U16_ChgVvsSOC_Def.

In one embodiment, it is determined whether the battery management system BMS is powered on for the first time. If so, the default data stored in U16_ChgVvsSOC_Def is assigned to the new variable U16_ChgVvsSOC_Upt so that it can be used during actual operation.

In one embodiment, when it is determined that the temperature of the lithium iron phosphate battery is not greater than the preset temperature threshold, the program is run this time and no online learning of new data is performed. Preferably, the preset temperature threshold is 0°C.

In one embodiment, the charging process temporary table variable U16_ChgVvsSOC_temp is set inside the battery management system BMS program. The data type is uint16 and the size is 3×11. It is used to record the voltage of each single cell of the lithium iron phosphate battery during the charging process. , current and temperature data; as shown in Figure 4, Figure 4 is a schematic diagram of the temporary table variable U16_ChgVvsSOC_temp during the charging process.

In one embodiment, the first voltage of each single cell in the lithium iron phosphate battery is obtained for each integrated battery charge state variable within the preset integrated battery charge state variable range, and based on the first voltage , when the maximum first voltage corresponding to each integrated battery charge state variable is obtained, steps S11-S16 are specifically included.

S11: Obtain the default voltage sequence of the lithium iron phosphate battery, and at the same time obtain the integrated battery charge state variable of the lithium iron phosphate battery.

In step S11, the charging process temporary table variable U16_ChgVvsSOC_temp is obtained, and the voltage values stored in the charging process temporary table variable U16_ChgVvsSOC_temp are sorted to obtain the default voltage sequence of the lithium iron phosphate battery; wherein, based on its size: It can be seen from 3×11 that the length of the default voltage sequence is a numerical variable of 11, as shown in Figure 5, which is a schematic diagram of the default voltage sequence.

In step S11, the initial value of the integrated battery charge state variable is obtained, and the initial value of the integrated battery charge state variable is substituted into the integrated battery charge state variable calculation formula to calculate the integrated battery charge state variable of the lithium iron phosphate battery, where , the calculation formula of the integrated battery charge state variable is as follows:

Among them, SOC ₀ is the initial value of the integrated battery charge state variable, which is the SOC _AH stored when the power was last turned off. It is obtained as the initial value by reading the memory when the power is turned on this time; i is the current; Q_max is the normal temperature nominal rating of the battery. capacity.

S12: Determine whether the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range. If not, obtain each of the lithium iron phosphate batteries under the integrated battery charge state variable. Based on the first voltages of each single cell, the maximum first voltage corresponding to the integrated battery charge state variable is obtained based on the plurality of first voltages.

In step S12, the maximum integrated battery charge state variable is 100%. When it is determined that the integrated battery charge state variable is not the maximum integrated battery charge state variable within the preset integrated battery charge state variable range, it is considered that the phosphoric acid The lithium iron battery is still charging.

In step S12, since in common lithium iron phosphate batteries, the number of single cells is generally about 2 to 20, therefore, based on the currently calculated integrated battery charge state variable, the integrated battery charge state variable is obtained Based on the first voltage of each single cell in the lithium iron phosphate battery, based on multiple first voltages, the maximum first voltage corresponding to the integrated battery charge state variable is obtained, that is, the integrated battery charge state variable is determined The maximum voltage of a single cell in a lithium iron phosphate battery.

In step S12, the first current of each single cell in the lithium iron phosphate battery under the integrated battery charge state variable is also obtained. Based on the multiple first currents, the integrated battery charge state variable corresponding to the first current is obtained. Maximum first current.

In step S12, the first temperature of each single cell in the lithium iron phosphate battery under the integrated battery charge state variable is also obtained, and based on the multiple first temperatures, the value corresponding to the integrated battery charge state variable is obtained. Minimum first temperature.

S13: After obtaining the maximum first voltage corresponding to the integrated battery charge state variable, perform leftward translation processing on the default voltage sequence, delete the first default voltage sequence variable in the default voltage sequence, and The maximum first voltage is placed at the last position of the default voltage sequence as the last default voltage sequence variable of the default voltage sequence.

In step S13, the default voltage sequence is moved as shown in Figure 6. Figure 6 is a schematic diagram of the movement of the default voltage sequence. Starting from the left, the previous unit is overwritten with the data of the next unit in sequence, and finally covered with new data. The data of the last unit completes the translation processing of the data.

In step S13, when it is determined that the integrated battery charge state variable of the lithium iron phosphate battery changes by 1%, the voltage, current and temperature data corresponding to each single cell in the current lithium iron phosphate battery are recorded, based on The voltage, current and temperature data corresponding to each single cell are obtained, and the maximum first voltage, maximum first current and minimum first temperature corresponding to the integrated battery charge state variable are obtained, and the maximum first voltage, maximum first The current and the lowest first temperature are respectively stored in the charging process temporary table variable U16_ChgVvsSOC_temp set internally in the battery management system BMS program. When the default voltage sequence is moved, the current, voltage and temperature in the charging process temporary table variable U16_ChgVvsSOC_temp are simultaneously stored. Shift the entire data one space to the left, and then record the current maximum first voltage, maximum first current, and minimum first temperature at the corresponding places at the end of the table.

S14: Reacquire the current integrated battery charge state variable. When it is determined that there is a change between the current integrated battery charge state variable and the integrated battery charge state variable, use the current integrated battery charge state variable as the integrated battery charge state variable. , and re-determine whether the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range.

S15: Until it is determined that the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range, and there is no change between the current integrated battery charge state variable and the integrated battery charge state variable. , obtain the current default voltage sequence.

S16: Based on the current default voltage sequence, obtain the maximum first voltage corresponding to each integrated battery charge state variable.

Step 102: Select the default voltage corresponding to each integrated battery charge state variable, calculate the first voltage difference between each maximum first voltage and the corresponding default voltage, and obtain the maximum first voltage among all first voltage differences. Difference.

In one embodiment, a plurality of first single cells are selected, and after confirming that the first single cells are in a discharged state, the plurality of first single cells are placed in an environment with a first preset temperature. After the static treatment, the plurality of first single cells are charged respectively, and during the charging process, each first single cell is recorded within the preset integrated battery charge state variable range. The voltage data corresponding to the integrated battery charge state variable.

Specifically, a plurality of first single cell cells are selected, and the plurality of first single cell cells are discharged at normal temperature until the voltage of the plurality of first single cell cells reaches the cut-off voltage, It is determined that the first single cell is in a discharged state.

Preferably, the number of the plurality of first single cells is set to three.

Specifically, the plurality of first single cells are placed in an environment with a first preset temperature for 6 hours, where the first preset temperature is 0°C.

Specifically, it is charged with the specified current in the charging map table until SOC = 100%, that is, fully charged, as shown in Figure 7, which is a representation of the charging map.

Specifically, the preset integrated battery charge state variable range is SOC=90%-100%, and each first integrated battery charge state variable is SOC=90%, 91%, 92%, 93%, 94%, 95 %, 96%, 97%, 98%, 99% and 100%. During the charging process, the voltage data of each 1% SOC of multiple first single cells in the process of SOC=90%-100% are respectively recorded.

In one embodiment, all voltage data corresponding to each first integrated battery charge state variable are averaged to obtain first average voltage data, and the first average voltage data is used as the first average voltage data at the first preset temperature. The first default voltage corresponding to each first integrated battery charge state variable.

Specifically, voltage data of multiple first single cells under each first integrated battery charge state variable are obtained, and first average voltage data is calculated for all voltage data under each first integrated battery charge state variable.

In one embodiment, a plurality of second single cells are selected, and after confirming that the second single cells are in a discharged state, the plurality of second single cells are placed in an environment with a second preset temperature. After the static treatment, the plurality of second single cells are charged respectively, and during the charging process, each second single cell is recorded within the preset integrated battery charge state variable range. The voltage data corresponding to the two integrated battery charge state variables.

Specifically, a plurality of second single cell cells are selected, and the plurality of second single cell cells are discharged at normal temperature until the voltage of the plurality of second single cell cells reaches the cut-off voltage, It is determined that the second single cell is in a discharged state.

Preferably, the number of the plurality of second single cells is set to three.

Specifically, the plurality of second single cells are placed in an environment with a second preset temperature for 6 hours, where the second preset temperature is 15°C.

Specifically, charge it with the specified current in the charging map table until SOC = 100%, that is, full charge.

Specifically, the preset integrated battery charge state variable range is SOC=90%-100%, and each second integrated battery charge state variable is SOC=90%, 91%, 92%, 93%, 94%, 95 %, 96%, 97%, 98%, 99% and 100%. During the charging process, the voltage data of each 1% SOC of multiple second single cells during the SOC=90%-100% process are respectively recorded.

Preferably, each second integrated battery charge state variable within the preset integrated battery charge state variable range has the same value as each first integrated battery charge state variable within the preset integrated battery charge state variable range.

In one embodiment, all voltage data corresponding to each second integrated battery charge state variable are averaged to obtain second average voltage data, and the second average voltage data is used as the second preset temperature. The second default voltage corresponding to each second integrated battery charge state variable.

Specifically, second voltage data of multiple second single cells under each second integrated battery charge state variable are obtained, and second average voltage data is calculated for all voltage data under each second integrated battery charge state variable. .

In one embodiment, a plurality of third single cell cells are selected, and after confirming that the third single cell cell is in a discharged state, the plurality of third single cell cells are placed in an environment with a second preset temperature. After the static treatment, the plurality of third single cells are charged respectively, and during the charging process, each third integral of each third sample battery within the preset integral battery charge state variable range is recorded. Voltage data corresponding to the battery charge state variable.

Specifically, a plurality of third single cell cells are selected, and the plurality of third single cell cells are discharged at normal temperature until the voltage of the plurality of third single cell cells reaches the cut-off voltage, It is determined that the third single cell is in a discharged state.

Preferably, the number of the plurality of third single cells is set to three.

Specifically, the plurality of third single cells are placed in an environment at a third preset temperature for 6 hours, where the second preset temperature is 25°C.

Specifically, charge it with the specified current in the charging map table until SOC = 100%, that is, full charge.

Specifically, the preset integrated battery charge state variable range is SOC=90%-100%, and each third integrated battery charge state variable is SOC=90%, 91%, 92%, 93%, 94%, 95 %, 96%, 97%, 98%, 99% and 100%. During the charging process, the voltage data of each 1% SOC of multiple third single cells in the process of SOC=90%-100% are recorded.

Preferably, each third integrated battery charge state variable within the preset integrated battery charge state variable range is respectively associated with each first integrated battery charge state variable within the preset integrated battery charge state variable range and the The value of each second integrated battery charge state variable within the preset integrated battery charge state variable range is the same.

In one embodiment, all voltage data corresponding to each third integrated battery charge state variable are averaged to obtain third average voltage data, and the third average voltage data is used as the third preset temperature. The third default voltage corresponding to each third integrated battery charge state variable.

Specifically, third voltage data of multiple third single cells under each third integrated battery charge state variable are obtained, and third average voltage data is calculated for all voltage data under each third integrated battery charge state variable. .

In one embodiment, after obtaining the first average voltage data, the second average voltage data and the third average voltage data, based on the first average voltage data, the second average voltage data and the third average voltage data , an initial voltage and SOC relationship data table is obtained. The initial voltage and SOC relationship data table records a set of corresponding relationship tables between voltages and SOC at different temperatures.

Preferably, the obtained data table of the relationship between initial voltage and SOC is stored in the second table variable U16_ChgVvsSOC_Def set internally in the BMS program of the battery management system.

In one embodiment, the first battery temperature corresponding to each integrated battery charge state variable within the preset integrated battery charge state variable range of the lithium iron phosphate battery is obtained, and the first battery temperature corresponding to multiple integrated battery charge state variables is obtained. battery temperature.

Specifically, based on the temporary table variables of the charging process, the first battery temperature corresponding to each integrated battery charge state variable within the preset integrated battery charge state variable range during the charging process of the lithium iron phosphate battery is obtained.

In one embodiment, the first battery temperature corresponding to each integrated battery charge state variable is obtained to obtain multiple first battery temperatures, and the average value of the multiple first battery temperatures is calculated to obtain the first battery temperature. Average value; determine the preset temperature corresponding to each integrated battery charge state variable based on the first battery temperature average, and select the default voltage corresponding to each integrated battery charge state variable based on the preset temperature .

Specifically, after the first battery temperature average is calculated, the first battery temperature average is compared with a preset temperature, where the preset temperatures include 0°C, 15°C and 25°C; when the first When the average battery temperature is greater than 0°C, but not greater than 15°C, determine the preset temperature corresponding to each integrated battery charge state variable to be 0°C. When the average temperature of the first battery is greater than 15°C, but not greater than 25°C When the first battery temperature average value is greater than 25°C, the preset temperature corresponding to each integrated battery charge state variable is determined to be 25°C. ℃.

Specifically, based on the preset temperature, the default voltage corresponding to each integrated battery charge state variable is selected from the initial voltage and SOC relationship data table.

In one embodiment, after obtaining the maximum first voltage corresponding to each integrated battery charge state variable, it is also necessary to perform a validity judgment on the obtained maximum first voltage corresponding to each integrated battery charge state variable, by The maximum first voltage corresponding to each integrated battery charge state variable is subtracted from the default voltage corresponding to each integrated battery charge state variable, and the first voltage difference corresponding to each integrated battery charge state variable is calculated, and based on all The first pressure difference is to obtain the maximum first pressure difference.

Step 103: When it is determined that the maximum first voltage difference is greater than the preset voltage difference threshold, obtain the backup voltage corresponding to each integrated battery charge state variable, and calculate the second value of each maximum first voltage and the corresponding backup voltage. pressure difference to obtain the largest second pressure difference among all second pressure differences.

In one embodiment, the preset pressure difference threshold is 5mv.

In one embodiment, when it is determined that the maximum first voltage difference is greater than the preset voltage difference threshold, it is considered that the learning data this time is doubtful, and the backup voltage corresponding to each integrated battery charge state variable is obtained, where the backup voltage is The voltage data is stored in the backup variable U16_ChgVvsSOC_Bckup.

In one embodiment, the second maximum voltage corresponding to each integrated battery charge state variable is calculated by subtracting the maximum first voltage corresponding to each integrated battery charge state variable from the backup voltage corresponding to each integrated battery charge state variable. pressure difference, and based on all second pressure differences, obtain the maximum second pressure difference.

Preferably, when it is determined that the maximum first pressure difference is greater than the preset pressure difference threshold, it is also determined whether U8_NeedSecondVerify is set. If not, the adjustment variable U8_NeedSecondVerify is set, and the corresponding value of each integrated battery charge state variable is set. The maximum first voltage is stored in the backup variable U16_ChgVvsSOC_Bckup, which is used for the secondary validity judgment of the next learned data. At the same time, the flag U8_NeedSecondVerify is set to stop this learning.

In one embodiment, when it is determined that the maximum first voltage difference is not greater than the preset voltage difference threshold, this learning is considered to be effective, and the maximum first voltage corresponding to each integrated battery charge state variable is used as the The default voltage corresponding to each integrated battery charge state variable, and the default voltage corresponding to each integrated battery charge state variable is stored in the first table variable U16_ChgVvsSOC_Upt to complete this learning and realize the online SOC correction point renew.

Step 104: When it is determined that the maximum second voltage difference is not greater than the preset voltage difference threshold, use the maximum first voltage corresponding to the charge state variable of each integrated battery as the charge state of each integrated battery. The variable corresponds to the default voltage.

In one embodiment, when it is determined that the maximum second voltage difference is not greater than the preset pressure difference threshold, this learning is considered to be effective, and the maximum first voltage corresponding to each integrated battery charge state variable is regarded as After the default voltage corresponding to each integrated battery charge state variable is stored, the default voltage corresponding to each integrated battery charge state variable is stored in the first table variable U16_ChgVvsSOC_Upt to complete this learning and realize SOC correction. Points of online updates.

In one embodiment, when it is determined that the maximum second pressure difference is greater than the preset pressure difference threshold, it is considered that the learning data this time is doubtful, and it is also determined whether U8_NeedSecondVerify is set. If not, the adjustment variable U8_NeedSecondVerify is set, and The maximum first voltage corresponding to each integrated battery charge state variable is used as the backup voltage corresponding to each integrated battery charge state variable, and is stored in the backup variable U16_ChgVvsSOC_Bckup for the next acquisition of data. The second validity is determined, and the flag U8_NeedSecondVerify is set at the same time to stop this learning.

Embodiment 2. Refer to Figure 2. Figure 2 is a schematic structural diagram of an embodiment of a device for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery provided by the present invention. As shown in Figure 2, the device includes a first voltage The acquisition module 201, the first verification module 202, the second verification module 203 and the first default voltage update module 204 are as follows:

The first voltage acquisition module 201 is used to acquire each voltage within the preset integrated battery charge state variable range when it is determined that the lithium iron phosphate battery enters the charging state and the temperature of the lithium iron phosphate battery is greater than the preset temperature threshold. Under the integrated battery charge state variable, the first voltage of each single cell in the lithium iron phosphate battery is obtained, and based on the first voltage, the maximum first voltage corresponding to each integrated battery charge state variable is obtained.

The first verification module 202 is used to select the default voltage corresponding to each integrated battery charge state variable, calculate the first voltage difference between each maximum first voltage and the corresponding default voltage, and obtain all first voltages. The largest first pressure difference among the differences.

The second verification module 203 is configured to obtain the backup voltage corresponding to each integrated battery charge state variable when it is determined that the maximum first voltage difference is greater than the preset voltage difference threshold, and calculate the corresponding maximum first voltage and The second voltage difference of the backup voltage is the largest second voltage difference among all second voltage differences.

The first default voltage update module 204 is configured to update the maximum first voltage corresponding to each integrated battery charge state variable when it is determined that the maximum second voltage difference is not greater than the preset voltage difference threshold. As the default voltage corresponding to each integrated battery charge state variable.

In one embodiment, the first voltage acquisition module 201 is used to obtain the voltage of each single cell in the lithium iron phosphate battery under each integrated battery charge state variable within the preset integrated battery charge state variable range. The first voltage, and based on the first voltage, obtain the maximum first voltage corresponding to each integrated battery charge state variable, specifically including: obtaining the default voltage sequence of the lithium iron phosphate battery, and obtaining the lithium iron phosphate battery at the same time The integrated battery charge state variable; determine whether the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range; if not, obtain the phosphoric acid under the integrated battery charge state variable The first voltage of each single cell in the lithium iron battery is based on multiple first voltages to obtain the maximum first voltage corresponding to the integrated battery charge state variable; and after obtaining the integrated battery charge state variable corresponding to the first voltage After the maximum first voltage is reached, the default voltage sequence is shifted to the left, the first default voltage sequence variable in the default voltage sequence is deleted, and the maximum first voltage is placed at the end of the default voltage sequence. The last bit, as the last bit of the default voltage sequence variable of the default voltage sequence; re-obtain the current integrated battery charge state variable, and when it is determined that there is a change between the current integrated battery charge state variable and the integrated battery charge state variable, The current integrated battery charge state variable is used as the integrated battery charge state variable, and it is re-determined whether the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range; until it is determined that the integrated battery charge state variable is When the integrated battery charge state variable is the maximum integrated battery charge state variable within the preset integrated battery charge state variable range, and there is no change between the current integrated battery charge state variable and the integrated battery charge state variable, the current default voltage sequence is obtained ; Based on the current default voltage sequence, obtain the maximum first voltage corresponding to each integrated battery charge state variable.

In one embodiment, the first verification module 202 is used to select the default voltage corresponding to each integrated battery charge state variable, and further includes: selecting a plurality of first single cells, and confirming that the first The single battery cells are in an empty state, and after the plurality of first single battery cells are placed in an environment with a first preset temperature for static treatment, the plurality of first single battery cells are charged respectively. , and during the charging process, record the voltage data corresponding to each first integrated battery charge state variable of each first single cell within the preset integrated battery charge state variable range; for each first integrated battery charge state variable All corresponding voltage data are averaged to obtain average voltage data, and the average voltage data is used as the first default voltage corresponding to each first integrated battery charge state variable at the first preset temperature; select multiple For the second single cell, after confirming that the second single cell is in an empty state and placing the plurality of second single cells in an environment with a second preset temperature for static processing, respectively Charge the plurality of second single cells, and during the charging process, record the value of each second single cell corresponding to each second integrated battery charge state variable within the preset integrated battery charge state variable range. Voltage data; average all voltage data corresponding to the charge state variable of each second integrated battery to obtain average voltage data, and use the average voltage data as each second integrated battery at the second preset temperature. The second default voltage corresponding to the charge state variable; select a plurality of third single cell cells, confirm that the third single cell cell is in a discharge state, and place the plurality of third single cell cells in the second After standing in an environment with a preset temperature, the plurality of third single cells are charged respectively, and during the charging process, it is recorded that each third sample battery is within the preset integrated battery charge state variable range. Voltage data corresponding to each third integrated battery charge state variable; average all voltage data corresponding to each third integrated battery charge state variable to obtain average voltage data, and use the average voltage data as the third integrated battery charge state variable A third default voltage corresponding to each third integrated battery charge state variable at three preset temperatures.

In one embodiment, an embodiment of the present invention provides a device for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery, further comprising: a first battery temperature acquisition module.

In one embodiment, the first battery temperature acquisition module is used to acquire the first battery temperature corresponding to each integrated battery charge state variable of the lithium iron phosphate battery within the preset integrated battery charge state variable range, and obtain multiple The first battery temperature corresponding to the integrated battery state of charge variable.

In one embodiment, the first verification module 202 is used to select the default voltage corresponding to each integrated battery charge state variable, and further includes: obtaining the first battery corresponding to each integrated battery charge state variable. temperature, obtain multiple first battery temperatures, calculate the average of the multiple first battery temperatures, and obtain the first battery temperature average; determine the charge state of each integrated battery based on the first battery temperature average The preset temperature corresponding to the variable is based on the preset temperature, and the default voltage corresponding to each integrated battery charge state variable is selected.

In one embodiment, an embodiment of the present invention provides a device for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery, further comprising: a backup voltage update module.

In one embodiment, the backup voltage update module is further configured to, when it is determined that the maximum second voltage difference is greater than the preset voltage difference threshold, update the maximum third value corresponding to each integrated battery charge state variable. A voltage is used as the backup voltage corresponding to each integrated battery charge state variable.

In one embodiment, an embodiment of the present invention provides a device for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery, further comprising: a second default voltage update module.

In one embodiment, the second default voltage update module is configured to update the maximum first voltage corresponding to each integrated battery charge state variable when it is determined that the maximum first voltage difference is not greater than a preset voltage difference threshold. A voltage serves as the default voltage corresponding to each integrated battery charge state variable.

Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working process of the device described above can be referred to the corresponding process in the foregoing method embodiment, and will not be described again here.

It should be noted that the above embodiments of the voltage value updating device for the SOC correction point of the lithium iron phosphate battery are only illustrative. The modules described as separate components may or may not be physically separated and are shown as modules. The components may or may not be physical units, that is, they may be located in one place, or they may be distributed across multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

Based on the above embodiments of the method for updating the voltage value of the SOC calibration point of the lithium iron phosphate battery, another embodiment of the present invention provides a terminal device for updating the voltage value of the SOC calibration point of the lithium iron phosphate battery. A terminal device for updating the voltage value of a battery SOC correction point includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, the present invention is implemented. A method for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery according to any embodiment of the invention is disclosed.

For example, in this embodiment, the computer program can be divided into one or more modules, and the one or more modules are stored in the memory and executed by the processor to complete the present invention. invention. The one or more modules may be a series of computer program instruction segments capable of completing specific functions. The instruction segments are used to describe the execution of the computer program in the voltage value update terminal device of the lithium iron phosphate battery SOC calibration point. process.

The terminal device for updating the voltage value of the SOC calibration point of the lithium iron phosphate battery can be a computing device such as a desktop computer, a notebook, a handheld computer, a cloud server, etc. The terminal device for updating the voltage value of the SOC calibration point of the lithium iron phosphate battery may include, but is not limited to, a processor and a memory.

The so-called processor can be a central processing unit (Central Processing Unit, CPU), or other general-purpose processor, digital signal processor (Digital Signal Processor, DSP), application specific integrated circuit (Application Specific Integrated Circuit, ASIC), off-the-shelf processor Programmable gate array (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general processor can be a microprocessor or the processor can be any conventional processor, etc. The processor is the control center of the terminal device for updating the voltage value of the SOC calibration point of the lithium iron phosphate battery, using various interfaces. The voltage value of the SOC calibration point of the entire lithium iron phosphate battery is connected with the line to update various parts of the terminal equipment.

The memory may be used to store the computer program and/or module, and the processor implements the phosphate by running or executing the computer program and/or module stored in the memory, and calling data stored in the memory. The voltage value of the SOC calibration point of the iron lithium battery updates various functions of the terminal equipment. The memory may mainly include a stored program area and a stored data area, wherein the stored program area may store an operating system, at least one application required for a function, etc.; the stored data area may store data created based on the use of the mobile phone, etc. In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart memory card (SmartMedia Card, SMC), secure digital (Secure Digital, SD) card, Flash Card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.

Based on the above embodiment of the method for updating the voltage value of the SOC correction point of the lithium iron phosphate battery, another embodiment of the present invention provides a storage medium, the storage medium includes a stored computer program, wherein in the computer When the program is running, the device where the storage medium is located is controlled to execute the voltage value updating method of the SOC calibration point of the lithium iron phosphate battery according to any embodiment of the present invention.

In this embodiment, the above-mentioned storage medium is a computer-readable storage medium, and the computer program includes computer program code. The computer program code may be in the form of source code, object code, executable file, or some intermediate form, etc. . The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording media, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM, Read-OnlyMemory) , Random Access Memory (RAM, Random Access Memory), electrical carrier signals, telecommunications signals, and software distribution media, etc. It should be noted that the content contained in the computer-readable medium can be appropriately added or deleted according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium Excludes electrical carrier signals and telecommunications signals.

In summary, the present invention provides a method and device for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery. When it is determined that the lithium iron phosphate battery enters the charging state and the temperature of the lithium iron phosphate battery is greater than the preset temperature threshold, Obtain the first voltage of each single cell in the lithium iron phosphate battery under each integrated battery charge state variable within the preset integrated battery charge state variable range, and obtain each integral based on the first voltage The maximum first voltage corresponding to the battery charge state variable; select the default voltage corresponding to each integrated battery charge state variable, calculate the first voltage difference between each maximum first voltage and the corresponding default voltage, and obtain all first The maximum first pressure difference in the pressure difference; when it is determined that the maximum first pressure difference is greater than the preset pressure difference threshold, the backup voltage corresponding to each integrated battery charge state variable is obtained, and each maximum first voltage and the corresponding The second pressure difference of the backup voltage is used to obtain the maximum second pressure difference among all second pressure differences; when it is determined that the maximum second pressure difference is not greater than the preset pressure difference threshold, each integral The maximum first voltage corresponding to the battery charge state variable is used as the default voltage corresponding to each integrated battery charge state variable; compared with the existing technology, the technical solution of the present invention can achieve SOC correction of lithium iron phosphate batteries The voltage value of the point is updated while avoiding the problem of poor applicability of the calibration point caused by inconsistent battery cells.

The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be made. regarded as the protection scope of the present invention.

Claims (10)

1. The method for updating the voltage value of the SOC correction point of the lithium iron phosphate battery is characterized by comprising the following steps of:

when it is determined that a lithium iron phosphate battery enters a charging state and the temperature of the lithium iron phosphate battery is greater than a preset temperature threshold, acquiring a first voltage of each single core in the lithium iron phosphate battery under each integral battery charge state variable in a preset integral battery charge state variable range, and acquiring a maximum first voltage corresponding to each integral battery charge state variable based on the first voltage;

selecting a default voltage corresponding to each integrated battery charge state variable, and calculating a first differential pressure between each maximum first voltage and the corresponding default voltage to obtain a maximum first differential pressure in all first differential pressures;

when the maximum first differential pressure is determined to be larger than a preset differential pressure threshold, acquiring standby voltage corresponding to each integral battery charge state variable, and calculating second differential pressure of each maximum first voltage and the corresponding standby voltage to obtain the maximum second differential pressure in all second differential pressures;

And when the maximum second differential pressure is not larger than the preset differential pressure threshold, taking the maximum first voltage corresponding to each integral battery charge state variable as the default voltage corresponding to each integral battery charge state variable.

2. The method for updating a voltage value of an SOC correction point of a lithium iron phosphate battery according to claim 1, wherein the method for updating a voltage value of an SOC correction point of a lithium iron phosphate battery is characterized by obtaining a first voltage of each single cell in the lithium iron phosphate battery under each integrated battery state of charge variable within a preset integrated battery state of charge variable range, and obtaining a maximum first voltage corresponding to each integrated battery state of charge variable based on the first voltage, and specifically includes:

acquiring a default voltage sequence of the lithium iron phosphate battery, and simultaneously acquiring an integral battery charge state variable of the lithium iron phosphate battery;

judging whether the integral battery charge state variable is the maximum integral battery charge state variable within a preset integral battery charge state variable range, if not, acquiring first voltage of each single core of the lithium iron phosphate battery under the integral battery charge state variable, and acquiring the maximum first voltage corresponding to the integral battery charge state variable based on a plurality of first voltages;

After the maximum first voltage corresponding to the integral battery charge state variable is obtained, carrying out left translation processing on the default voltage sequence, deleting a first default voltage sequence variable in the default voltage sequence, and placing the maximum first voltage at the last position of the default voltage sequence as a last default voltage sequence variable of the default voltage sequence;

acquiring a current integral battery charge state variable again, taking the current integral battery charge state variable as the integral battery charge state variable when judging that the current integral battery charge state variable and the integral battery charge state variable change, and judging whether the integral battery charge state variable is the maximum integral battery charge state variable within a preset integral battery charge state variable range again;

acquiring a current default voltage sequence until the integral battery charge state variable is judged to be the maximum integral battery charge state variable within a preset integral battery charge state variable range and the current integral battery charge state variable and the integral battery charge state variable are unchanged;

And obtaining the maximum first voltage corresponding to each integrated battery charge state variable based on the current default voltage sequence.

3. The method for updating the voltage value of the SOC calibration point of a lithium iron phosphate battery according to claim 1, further comprising, before selecting the default voltage corresponding to each integrated battery state of charge variable:

selecting a plurality of first single battery cells, after confirming that the first single battery cells are in an empty state, placing the plurality of first single battery cells in an environment with a first preset temperature for standing treatment, respectively charging the plurality of first single battery cells, and recording voltage data corresponding to each first integral battery charge state variable of each first single battery cell in a preset integral battery charge state variable range in the charging process;

averaging all voltage data corresponding to each first integrated battery charge state variable to obtain average voltage data, and taking the average voltage data as a first default voltage corresponding to each first integrated battery charge state variable at the first preset temperature;

selecting a plurality of second single battery cells, after confirming that the second single battery cells are in an empty state, placing the second single battery cells in an environment with a second preset temperature for standing treatment, respectively charging the second single battery cells, and recording voltage data corresponding to each second integral battery charge state variable of each second single battery cell in a preset integral battery charge state variable range in the charging process;

Carrying out averaging treatment on all voltage data corresponding to each second integral battery charge state variable to obtain average voltage data, and taking the average voltage data as a second default voltage corresponding to each second integral battery charge state variable at the second preset temperature;

selecting a plurality of third single battery cells, after confirming that the third single battery cells are in an empty state, placing the third single battery cells in an environment with a second preset temperature for standing treatment, respectively charging the third single battery cells, and recording voltage data corresponding to each third integrated battery charge state variable of each third sample battery in a preset integrated battery charge state variable range in the charging process;

and carrying out averaging treatment on all voltage data corresponding to each third integrated battery charge state variable to obtain average voltage data, and taking the average voltage data as a third default voltage corresponding to each third integrated battery charge state variable at the third preset temperature.

4. The method for updating a voltage value of an SOC calibration point of a lithium iron phosphate battery according to claim 3, further comprising:

And acquiring a first battery temperature corresponding to each integral battery charge state variable of the lithium iron phosphate battery in a preset integral battery charge state variable range, and acquiring the first battery temperatures corresponding to a plurality of integral battery charge state variables.

5. The method for updating a voltage value of an SOC calibration point of a lithium iron phosphate battery according to claim 4, wherein selecting a default voltage corresponding to each integrated battery state of charge variable further comprises:

acquiring the first battery temperature corresponding to each integrated battery charge state variable to obtain a plurality of first battery temperatures, and calculating an average value of the plurality of first battery temperatures to obtain a first battery temperature average value;

and determining a preset temperature corresponding to each integral battery charge state variable according to the first battery temperature average value, and selecting a default voltage corresponding to each integral battery charge state variable based on the preset temperature.

6. The method for updating the voltage value of the SOC correction point of a lithium iron phosphate battery according to claim 1, further comprising:

and when the maximum second differential pressure is determined to be larger than the preset differential pressure threshold, taking the maximum first voltage corresponding to each integrated battery charge state variable as the standby voltage corresponding to each integrated battery charge state variable.

7. The method for updating the voltage value of the SOC correction point of a lithium iron phosphate battery according to claim 1, further comprising:

and when the maximum first differential pressure is not larger than a preset differential pressure threshold, taking the maximum first voltage corresponding to each integral battery charge state variable as the default voltage corresponding to each integral battery charge state variable.

8. The utility model provides a voltage value updating device of lithium iron phosphate battery SOC correction point which characterized in that includes: the device comprises a first voltage acquisition module, a first verification module, a second verification module and a first default voltage updating module;

the first voltage obtaining module is used for obtaining a first voltage of each single core of the lithium iron phosphate battery under each integral battery charge state variable in a preset integral battery charge state variable range when the lithium iron phosphate battery is determined to enter a charge state and the temperature of the lithium iron phosphate battery is greater than a preset temperature threshold value, and obtaining a maximum first voltage corresponding to each integral battery charge state variable based on the first voltage;

the first verification module is used for selecting a default voltage corresponding to each integrated battery charge state variable, and calculating a first differential pressure between each maximum first voltage and the corresponding default voltage to obtain a maximum first differential pressure in all first differential pressures;

The second verification module is used for acquiring standby voltage corresponding to each integral battery charge state variable when the maximum first differential pressure is determined to be greater than a preset differential pressure threshold value, and calculating second differential pressures of each maximum first voltage and the corresponding standby voltage to obtain the maximum second differential pressure in all the second differential pressures;

and the first default voltage updating module is configured to, when it is determined that the maximum second differential pressure is not greater than the preset differential pressure threshold, use the maximum first voltage corresponding to each integrated battery charge state variable as the default voltage corresponding to each integrated battery charge state variable.

9. A terminal device comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, the processor implementing the method for updating the voltage value of the lithium iron phosphate battery SOC correction point according to any of claims 1 to 7 when the computer program is executed.

10. A computer readable storage medium, characterized in that the computer readable storage medium comprises a stored computer program, wherein the computer program when run controls a device in which the computer readable storage medium is located to perform the method for updating the voltage value of the SOC correction point of the lithium iron phosphate battery according to any one of claims 1 to 7.