Calibration method, calibration device, battery pack and storage medium

Abstract

The invention discloses a calibration method, a calibration device, a battery pack and a storage medium. The method is used for a battery pack, and comprises the following steps: when the battery pack is in a standby state, acquiring the current voltage of the battery pack; based on the current voltage, determining a calibrated residual electric quantity, in the standby state, the voltage of the battery pack and the residual electric quantity having a preset mapping relationship; under the condition that the calibrated residual electric quantity is within a preset electric quantity range, estimating an electric quantity descending speed based on the calibrated residual electric quantity; and based on the electric quantity descending speed and an initial remaining electric quantity, displaying a target remaining electric quantity, the initial remaining electric quantity being calculated based on the current of the battery pack. The difference value between the initial residual electric quantity and the calibrated residual electric quantity can be gradually reduced until the initial residual electric quantity is the same as the calibrated residual electric quantity, calibration of the initial residual electric quantity is completed, the purpose of correcting the initial residual electric quantity is achieved, misjudgment of a user on the battery pack is avoided, and the use experience of the user is improved.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage power supply, and more specifically, to a calibration method, a calibration device, a battery pack, and a non-volatile computer-readable storage medium. Background Art

[0002] At present, for batteries with larger battery capacity (taking lithium iron phosphate batteries as an example), under low power consumption conditions, if the remaining charge percentage (State of Charge, SOC) is calculated based on the ampere-hour integration method through the collected battery current, due to the limitations of the hardware characteristics of the battery sensor, the collected battery current at this time usually has a large error, resulting in low accuracy of SOC, which affects the use of the battery. Summary of the invention

[0003] The embodiments of the present application provide a calibration method, a calibration device, a battery pack and a non-volatile computer-readable storage medium. The calculated SOC has a high accuracy, ensuring the normal use of the battery.

[0004] The calibration method of the present application is used for a calibration method for a battery pack, and the method includes: when the battery pack is in a standby state, obtaining the current voltage of the battery pack; determining the calibration remaining power based on the current voltage, and in the standby state, there is a preset mapping relationship between the voltage and the remaining power of the battery pack; when the calibration remaining power is within a preset power range, estimating the power decrease rate based on the calibration remaining power; based on the power decrease rate and the initial remaining power, displaying the target remaining power, and the initial remaining power is calculated based on the current of the battery pack.

[0005] In certain embodiments, when the current of the battery pack is less than a preset threshold, it is determined that the battery pack is in the standby state.

[0006] In some embodiments, the current voltage is the output voltage of the battery pack; or, the battery pack includes a plurality of battery cells, the plurality of battery cells are connected in parallel, and the current voltage is the voltage of any one of the battery cells.

[0007] In some embodiments, the preset power range includes multiple power ranges, and there is a positive correlation between the remaining power in the preset power range and the voltage of the battery pack.

[0008] In some embodiments, the preset power range includes a first preset power range and a second preset power range, the first preset power range is [0, 30%], and the second preset power range is [55%, 65%].

[0009] In some embodiments, the method further includes: displaying a target remaining power based on the initial remaining power when the calibrated remaining power is outside a preset power range.

[0010] In some embodiments, estimating the rate of power decrease based on the calibrated remaining power includes: estimating the rate of power decrease based on the calibrated remaining power and a detection current, wherein the detection current is determined based on at least one of a current current of the battery pack and a preset standby current.

[0011] In some embodiments, estimating the rate of power decrease based on the calibrated remaining power and the detection current includes: determining the time it takes for the calibrated remaining power to drop to the minimum power in a preset power range based on the calibrated remaining power and the detection current; and calculating the rate of power decrease based on the time and the initial remaining power.

[0012] In certain embodiments, the method further includes: displaying a target remaining power based on the initial remaining power when the battery pack is in a working state, and a current of the battery pack in the working state is greater than a current in the standby state.

[0013] The calibration device of the embodiment of the present application is used for a battery pack, and the device may include an acquisition module, a determination module, an estimation module and a display module. The acquisition module is used to acquire the current voltage of the battery pack when the battery pack is in a standby state; the determination module is used to determine the calibration remaining power based on the current voltage, and in the standby state, there is a preset mapping relationship between the voltage and the remaining power of the battery pack; the estimation module is used to estimate the power decrease speed based on the calibration remaining power when the calibration remaining power is within a preset power range; the display module is used to display the target remaining power based on the power decrease speed and the initial remaining power, and the initial remaining power is calculated based on the current of the battery pack.

[0014] The battery pack of an embodiment of the present application includes a processor, a memory; and a computer program, wherein the computer program is stored in the memory and executed by the processor, and the computer program includes instructions for executing the calibration method described in any of the above embodiments.

[0015] The non-volatile computer-readable storage medium of the embodiment of the present application includes a computer program. When the computer program is executed by a processor, the processor executes the calibration method described in any of the above embodiments.

[0016] The calibration method, calibration device, battery pack, and non-volatile computer-readable storage medium of the embodiments of the present application obtain the current voltage of the battery pack when the battery pack is in a standby state; since in the standby state, there is a preset mapping relationship between the voltage and the remaining power of the battery pack, the calibration remaining power is determined based on the current voltage to monitor the remaining power of the battery pack; when the calibration remaining power is within a preset power range, it can be considered that the calibration remaining power can accurately reflect the actual remaining power of the battery pack, and then based on the calibration remaining power, the power decrease rate is estimated; finally, based on the power decrease rate and the initial remaining power, the target remaining power is displayed, and the difference between the initial remaining power and the calibration remaining power can be gradually reduced until the initial remaining power is the same as the calibration remaining power, thereby completing the calibration of the initial remaining power and achieving the purpose of correcting the initial remaining power.

[0017] Moreover, since during the calibration process, the displayed target remaining power gradually approaches the calibration remaining power over time, the user cannot perceive the calibration process of the initial remaining power when checking the remaining power of the battery pack, which can prevent the user from misjudging the battery pack and improve the user experience.

[0018] Additional aspects and advantages of the embodiments of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0020] Figure 1 is a flow chart of a calibration method according to certain embodiments of the present application;

[0021] Figure 2 is a schematic diagram of a scenario of a calibration method in certain embodiments of the present application;

[0022] Figure 3 is a flow chart of a calibration method according to certain embodiments of the present application;

[0023] Figure 4 is a flow chart of a calibration method according to certain embodiments of the present application;

[0024] Figure 5 is a flow chart of a calibration method according to certain embodiments of the present application;

[0025] Figure 6 is a flow chart of a calibration method according to certain embodiments of the present application;

[0026] Figure 7is a schematic diagram of a module of a calibration device according to certain embodiments of the present application;

[0027] Figure 8 It is a schematic diagram of the structure of an energy storage power supply in some embodiments of the present application;

[0028] Fig. 9 It is a schematic diagram of the connection status of a non-volatile computer-readable storage medium and a processor in certain embodiments of the present application. DETAILED DESCRIPTION

[0029] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions from beginning to end. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the embodiments of the present application, and cannot be understood as limiting the embodiments of the present application.

[0030] To facilitate understanding of this application, the terms appearing in this application are explained below:

[0031] When using a battery, monitoring the remaining charge percentage (State of Charge, SOC) of the battery is crucial to the battery's charge and discharge status and safety.

[0032] At present, the battery SOC is generally calculated based on the Coulomb Counting method through the battery management system (BMS) (BMS is the hub for managing and monitoring power batteries and is used to manage, maintain and monitor each battery module). The Coulomb Counting method requires calculation based on the collected battery current.

[0033] However, for batteries with larger battery capacity (for example, lithium iron phosphate batteries), since lithium iron phosphate batteries have larger battery capacity and larger discharge power, the collected current is also larger. However, due to the hardware characteristics of the battery sensor, current sensors that meet the requirements of collecting large currents (for example, currents greater than 100 amperes (A)) usually have errors when collecting small currents (for example, currents less than 0.5A), and the ratio between the error value and the actual current value is usually between 30% and 50%; even the current sensor may not be able to collect the battery current.

[0034] Therefore, when the battery sensor cannot obtain the accurate current value (for example, the current value of the battery is less than the acquisition accuracy of the battery sensor; or the battery is in a low power consumption condition and the current value is small), since the error between the current collected by the current sensor and the actual current reaches 30% to 50%, the SOC calculated based on the ampere-hour integration method and the actual SOC of the battery will also have an error of 30% to 50%; and when the battery sensor cannot collect current, the BMS will not be able to calculate the SOC of the battery, resulting in abnormal discharge of the battery, etc., affecting the practical life of the battery.

[0035] Although it is possible to add a small current detection circuit and set up an additional current sensor to collect small current so that the BMS can calculate the SOC based on the ampere-hour integration method, the additional settings increase the production and use costs of the battery.

[0036] In order to solve the above technical problems, an embodiment of the present application provides a calibration method.

[0037] The calibration method of this application will be described in detail below:

[0038] See also Figure 1 The calibration method of the embodiment of the present application can be used for a battery pack, and the calibration method includes:

[0039] Step 011: When the battery pack is in standby mode, obtain the current voltage of the battery pack.

[0040] Optionally, the battery pack may be a battery pack including a lithium battery module (such as a ternary battery, a lithium iron phosphate battery, a lithium iron manganese phosphate battery, a sodium battery, etc.), a BMS module, a current acquisition module, a voltage acquisition module, an inverter system module, etc. This application is described by taking a lithium iron phosphate battery pack as an example.

[0041] Optionally, when the current of the battery pack is less than a preset current threshold, it is determined that the battery pack is in the standby state.

[0042] Among them, the preset current threshold can be 2, 1, 0.9, 0.8, 0.5 (unit: ampere (A)). It can be determined through experiments, table lookup, etc. that when the current of the battery pack is less than the preset current threshold, the battery pack is in standby mode.

[0043] It can be understood that when the current is less than 0.5A, the battery pack may have a problem of inaccurately collected current. Therefore, the preset current threshold may be greater than 0.5A and close to 0.5A.

[0044] Optionally, the current voltage of the battery pack is the output voltage of the battery pack; or, the battery pack includes a plurality of battery cells, the plurality of battery cells are connected in parallel, and the current voltage is the voltage of any battery cell.

[0045] The output voltage of the battery pack may be the output voltage across the battery pack when the battery pack is supplying power to a load or is in a standby state (a chemical reaction inside the battery pack is still ongoing).

[0046] The battery pack may include multiple battery cells, which are connected in parallel, and the voltage of the battery pack is basically the same as the voltage of any battery cell. Since the output voltage of the battery pack may be affected by the internal resistance of the battery pack or the resistance of the connection point, etc., the measured current voltage may have errors; while in the standby state, the electrochemical state of the battery cell is stable and can reflect the actual chemical state of the battery pack. Therefore, the voltage of any battery cell can be obtained as the current voltage of the battery pack. This application takes the current voltage of the battery pack as the voltage of any battery cell as an example for explanation.

[0047] It can be understood that if the selected battery cell has a fault, it will affect the accuracy of the current voltage of the battery pack. Therefore, by obtaining the output voltage of the battery and the voltage of any battery cell, when the voltage difference between the output voltage and the voltage of the battery cell is less than the preset voltage difference, it is considered that there is no fault in the battery cell, and the voltage of the battery cell is used as the output voltage of the battery pack.

[0048] Specifically, the voltage of the battery pack can be monitored (for example, by monitoring the voltage change threshold of the battery pack within a preset time, and determining that the battery pack is in a standby state when the voltage change threshold is less than the preset voltage threshold) or the current (when the current of the battery pack is less than the preset current threshold, determining that the battery pack is in a standby state), so that the BMS of the battery pack can determine that the battery pack is in a standby state (for another example, the controller of the battery pack may issue a standby control instruction, and the BMS switches the battery pack to a standby state in response to the standby control instruction). When the battery pack is in the standby state, the current voltage of the battery pack is obtained through, for example, a voltage sensor, a voltage collector, etc.

[0049] Step 012: Determine and calibrate the remaining power based on the current voltage. In the standby state, there is a preset mapping relationship between the voltage and the remaining power of the battery pack.

[0050] The remaining power may be the SOC of the battery pack, and the calibrated remaining power may be the actual SOC of the battery pack.

[0051] Specifically, see Figure 2When the battery pack is in standby mode (or not being charged or discharged), there is a preset mapping relationship between the voltage of the battery pack (the voltage of the battery cell) and the remaining power of the battery pack. According to the mapping relationship, the following can be established: Figure 2 The mapping relationship diagram is shown.

[0052] The mapping relationship can be the mapping relationship between the voltage of the battery pack and the SOC when the battery pack is not charged or discharged. Therefore, although the battery pack still has power output in the standby state, it has been found through experiments that the voltage difference between the voltage of the battery pack in the standby state and the voltage of the battery pack that is not charged or discharged is within 10 millivolts (mv). When determining the SOC through the mapping relationship, 10mv does not affect the accuracy of SOV. Therefore, the calibration remaining power of the battery pack can be determined based on the mapping relationship between the current voltage and the remaining capacity of the battery pack, and the calibration remaining power has high precision and accuracy, so as to monitor the remaining capacity of the battery pack.

[0053] Step 013: When the calibrated remaining power is within a preset power range, estimate the power reduction speed based on the calibrated remaining power.

[0054] The estimated power reduction speed may be an estimated speed at which the calibration remaining power is reduced to a preset intermediate remaining power (for example, the minimum value of a preset power range).

[0055] Optionally, the preset power range includes multiple power levels, and there is a positive correlation between the remaining power level in the preset power range and the voltage of the battery pack.

[0056] Among them, there is a positive correlation between the remaining power in the preset power range and the voltage of the battery pack, that is, there is a one-to-one correspondence between the remaining power in the preset power range and the voltage of the battery pack, and within the preset power range, the greater the voltage of the battery pack, the greater the remaining power of the battery pack.

[0057] Optionally, the preset power range includes a first preset power range and a second preset power range, the first preset power range is [0, 30%], and the second preset power range is [55%, 65%].

[0058] Please continue to read Figure 2 When the remaining power of the battery pack is in the range of [30%, 90%], the voltage of the battery pack changes within 100mv. Due to the difference between the voltages corresponding to the same SOC in different battery packs during the production process, it can reach about 50mv. Therefore, if the remaining power of the battery pack is in the range of [30%, 90%], the calibration remaining power of the battery pack determined by the mapping relationship and the current voltage is prone to errors. And, for another example, please continue to refer to Figure 2For example, when the remaining power of the battery pack is in the range of [30%, 55%], the voltage of the battery pack is around 3300mv. In other words, when the remaining power of the battery pack is in the range of [30%, 55%], it is difficult to determine the calibrated output power through the output voltage of the battery pack. Similarly, when the remaining power of the battery pack is in the range of [65%, 95%], it is also difficult to determine the calibrated output power.

[0059] When the remaining power of the battery pack is in the power range of [5%, 10%], although it is difficult to determine the actual calibrated output power of the battery pack through the output voltage of the battery pack, it is generally believed that the SOC error is tolerable within 5%. Therefore, the first preset power range is [0, 30%], and the second preset power range is [55%, 65%].

[0060] Optionally, the preset power range may further include a third preset power range, and the third preset power range is [95%, 100%].

[0061] Specifically, when the calibration remaining power is within the preset power range, it can be considered that the calibration remaining power can accurately reflect the actual remaining power of the battery pack. For example, the intermediate remaining power can be set (less than the calibration remaining power and within the preset power range), the remaining power difference between the calibration remaining power and the intermediate remaining power can be calculated, and then the ratio of the remaining power difference to the current of the battery pack can be calculated to determine the decrease time of the calibration remaining power to the intermediate remaining power, and the power decrease speed can be estimated according to the change of the calibration remaining power with the decrease time.

[0062] Step 014: Display the target remaining power based on the power decrease rate and the initial remaining power. The initial remaining power is calculated based on the current of the battery pack.

[0063] The initial remaining power can be obtained by collecting the current of the battery pack through a current sensor or the like, and calculating the current through the ampere-hour integration method.

[0064] Specifically, in the standby state, the initial remaining power calculated by the BMS based on the current of the battery pack through the ampere-hour integration method is difficult to reflect the actual remaining power of the battery pack. Therefore, the power decrease rate of the initial remaining power can be adjusted by estimating the power decrease rate of the actual remaining power of the battery pack (i.e., the calibration remaining power), and the target remaining power during the display process. The BMS can also control the battery pack to charge and discharge based on the target remaining power. For example, continuing with the previous example, the power decrease rate can be estimated and the decrease time can be determined based on the calibration remaining power and the intermediate remaining power. According to the decrease time, the decrease rate of the initial remaining power is adjusted so that the time for the displayed initial remaining power to drop to the intermediate remaining power is the same as the time for the calibration remaining power to drop to the intermediate remaining power, so as to complete the calibration of the initial remaining power and achieve the purpose of correcting the initial remaining power.

[0065] It can be understood that after determining the calibrated remaining power, if the calibrated remaining power is directly displayed as the target remaining power, it will manifest as an abnormal phenomenon of rapid or sudden changes in SOC, which may easily cause users to misjudge the status and health of the battery pack, affecting the user's experience.

[0066] However, in the calibration method of the present application, during the calibration process, the displayed target remaining power gradually approaches the calibration remaining power over time. When the user checks the remaining power of the battery pack, he cannot perceive the calibration process of the initial remaining power, which can avoid the user from misjudging the battery pack and improve the user experience.

[0067] In this way, when the battery pack is in standby mode, the current voltage of the battery pack is obtained; since in the standby mode, there is a preset mapping relationship between the voltage and the remaining power of the battery pack, the calibration remaining power is determined based on the current voltage to monitor the remaining power of the battery pack; when the calibration remaining power is within the preset power range, it can be considered that the calibration remaining power can accurately reflect the actual remaining power of the battery pack, and then based on the calibration remaining power, the power decrease rate is estimated; finally, based on the power decrease rate and the initial remaining power, the target remaining power is displayed, and the initial remaining power is calculated based on the current of the battery pack to obtain the time for the displayed initial remaining power to drop to the intermediate remaining power, which is the same as the time for the calibration remaining power to drop to the intermediate remaining power, so as to complete the calibration of the initial remaining power and achieve the purpose of correcting the initial remaining power.

[0068] Moreover, since during the calibration process, the displayed target remaining power gradually approaches the calibration remaining power over time, the user cannot perceive the calibration process of the initial remaining power when checking the remaining power of the battery pack, which can prevent the user from misjudging the battery pack and improve the user experience.

[0069] In addition, compared to the current method of obtaining current to improve the accuracy of SOC by adding a small current detection circuit, the present application does not require additional detection circuits, which can save the production and use costs of the battery pack.

[0070] See also Figure 3 In some embodiments, the calibration method further comprises:

[0071] Step 015: When the calibrated remaining power is outside the preset power range, the target remaining power is displayed based on the initial remaining power.

[0072] The amount outside the preset power range may include at least one of [30%, 55%] and [65%, 100%].

[0073] Specifically, when the calibration remaining power is outside the preset power range, the calibration remaining power determined at this time cannot reflect the actual remaining power of the battery pack. If the calibration remaining power is still used to perform relevant calculations to determine and display the target remaining power, the error in the determined and displayed target remaining power may be greater than the target remaining power determined and realized based on the initial remaining power, affecting the user's experience. Therefore, when the calibration remaining power is outside the preset power range, the target remaining power can be displayed based on the initial remaining power.

[0074] See also Figure 4 In some embodiments, step 013: estimating the rate of power reduction based on the calibration remaining power includes:

[0075] Step 0131: Based on the calibration of the remaining power and the detection current, the power reduction rate is estimated, and the detection current is determined based on at least one of the current current of the battery pack and the preset standby current.

[0076] The preset standby current may be an experimental value, an empirical value, etc. The preset standby current may be the current of the battery pack in the standby state. For example, assuming that the current values ​​of multiple battery packs in the standby state are obtained through experiments, the average value of the multiple current values ​​may be taken as the preset standby current.

[0077] The preset standby current may also be the power consumption current of the battery pack in the standby state, which is generally less than 0.05A. During calculation, the preset standby current may be considered as a fixed value (0.05A).

[0078] Specifically, taking the preset standby current as the power consumption current (0.05A) of the battery pack in the standby state as an example, the detection current can be the sum of the current current of the battery pack collected by the current sensor of the battery pack and the preset standby current. Since in the standby state, the current collected by the current sensor of the battery pack has an error of 30% to 50%, and since the discharge process of the battery in the standby state is relatively stable, the current reduction rate is usually proportional to the SOC decrease rate.

[0079] It can be understood that when calibrating the remaining power, take 1% remaining power as the intermediate remaining power as an example. If the detection current is directly determined based on the sum of the current current of the battery pack collected by the current sensor and the preset standby current, and the calibration remaining power is calculated to estimate the power drop rate, it may happen that during the calibration of the initial remaining power, the actual remaining capacity of the battery pack (calibration remaining power) has reached 1%, but the displayed target remaining power has not yet reached 1%. Since the SOC has reached 1%, the current voltage of the battery pack has dropped to the over-discharge protection voltage (the lowest voltage to protect the battery from damage due to excessive discharge when the battery pack is discharged). At this time, the BMS will force calibration of the displayed target remaining power, and the displayed target remaining power will jump to 1% (or 0%), affecting the user experience.

[0080] Therefore, when estimating the rate of power decrease based on the remaining power and the detection current, the detection current can be modulated with a maximum error, that is, the detection current is 1.5 times the sum of the current current of the battery pack and the preset standby current. Even if the error between the current current and the actual current is less than 50%, when the target power is displayed according to the rate of power decrease, the target power will only stay at 1% for a relatively long time, and there will be no SOC jump.

[0081] See also Figure 5 Optionally, step 0131: estimating the rate of power reduction based on the calibration remaining power and the detection current, including:

[0082] Step 01311: based on the calibration remaining power and the detection current, determining the time for the calibration remaining power to drop to the minimum power of the preset power range;

[0083] Step 01312: Calculate the rate at which the power level decreases based on the duration and the initial remaining power.

[0084] Specifically, see Figure 2, if the power drop speed is calculated directly based on the time it takes for the calibrated remaining power (assuming the preset power range is [55%, 65%]) to drop to any preset power range (taking [0, 30%] as an example), since the minimum difference between the two preset power ranges is also greater than the minimum error of 5% that can be tolerated when calculating SOC, it will cause a large error in the target remaining power during the display process. Therefore, the time T1 for the calibrated remaining power to drop to the minimum power of the preset power range can be determined by the calibrated remaining power and the detection current, and can be calculated by the following formula:

[0085] T1=(SOC1-SOC0)*C / (I*1.5)

[0086] Among them, SOC1 is the calibration remaining power, SOC0 is the minimum power in the preset power range where the calibration remaining power is located, C is the rated capacity of the battery pack, the unit is ampere-hour (Ah), I is the detection current, the detection current I is the sum of the current current I1 of the battery pack collected by the current sensor of the battery pack and the preset standby current I2, that is, I=I1+I2, where I2=0.05A; the units of I, I1 and I2 can all be A; the unit of T1 is hour (h).

[0087] In order to make the time length T2 for the initial remaining power SOC2 to drop to the minimum power of the preset power range where the calibration remaining power SOC1 is located the same as the time length T1 for the calibration remaining power SOC1 to drop to the minimum power of the preset power range where the calibration remaining power is located, so as to complete the correction and calibration of the initial remaining power SOC2, the power drop speed K can be calculated according to the time length T1 and the initial remaining power SOC2, which can be calculated by the following formula:

[0088] K=(SOC2-SOC0)*C / T2

[0089] T2=T1

[0090] The unit of K is ampere-hour per hour (Ah / H).

[0091] It can be understood that when the preset power range is [0, 30%], if the minimum value (0%) of the preset power range is directly used for calculation, when displaying the target remaining power, 0% SOC may be displayed for a long time, which is also easy to cause users to misjudge. Therefore, when the preset power range is [0, 30%], the power reduction speed K can be estimated by calculating the time it takes to calibrate the remaining power to 1% SOC, that is:

[0092] T1=(SOC1-1%)*C / (I*1.5)

[0093] K=(SOC2-1%)*C / T1

[0094] Among them, SOC1 is in the range of [0, 30%].

[0095] When the preset power range is [55%, 65%], K can be calculated by the following formula:

[0096] T1 = (SOC1-55%) * C / (I * 1.5)

[0097] K=(SOC2-55%)*C / T1

[0098] When the preset power range is [95%, 100%], K can be calculated by the following formula:

[0099] T1 = (SOC1-95%)*C / (I*1.5)

[0100] K=(SOC2-95%)*C / T1

[0101] It is understandable that in order to avoid the displayed target remaining power jumping upward, SOC1 <SOC2。

[0102] See also Figure 6 , optionally, the calibration method comprises:

[0103] Step 016: When the battery pack is in working state, the target remaining power is displayed based on the initial remaining power, and the current of the battery pack in the working state is greater than the current in the standby state.

[0104] Specifically, when the battery pack is in working condition, the current collected by the current sensor is no longer limited by accuracy and causes errors. Therefore, the current collected by the current sensor and the initial remaining power calculated by the ampere-hour integration method can reflect the SOC of the battery pack, and the target remaining power can be displayed based on the initial remaining power.

[0105] See also Figure 7In order to facilitate the better implementation of the calibration method of the embodiment of the present application, the embodiment of the present application also provides a calibration device 300. The calibration device 300 is used for a battery pack. The calibration device 300 may include an acquisition module 301, a determination module 302, an estimation module 303 and a display module 304. The acquisition module 301 is used to acquire the current voltage of the battery pack when the battery pack is in a standby state; the determination module 302 is used to determine the calibration remaining power based on the current voltage. In the standby state, there is a preset mapping relationship between the voltage and the remaining power of the battery pack; the estimation module 303 is used to estimate the power reduction speed based on the calibration remaining power when the calibration remaining power is within a preset power range; the display module 304 is used to display the target remaining power based on the power reduction speed and the initial remaining power, and the initial remaining power is calculated based on the current of the battery pack.

[0106] In some embodiments, the display module 304 may also be configured to display a target remaining power based on the initial remaining power when the calibrated remaining power is outside a preset power range.

[0107] In some embodiments, the estimation module 303 is specifically used to estimate the rate of power reduction based on the calibrated remaining power and the detection current, where the detection current is determined based on at least one of the current current of the battery pack and a preset standby current.

[0108] In some embodiments, the estimation module 303 is specifically used to determine the time it takes for the calibrated remaining power to drop to the minimum power of the preset power range based on the calibrated remaining power and the detection current; and calculate the power drop speed based on the time and the initial remaining power.

[0109] In some embodiments, the display module 304 can also be used to display the target remaining power based on the initial remaining power when the battery pack is in the working state, and the current of the battery pack in the working state is greater than the current in the standby state.

[0110] The calibration device 300 is described above from the perspective of functional modules in conjunction with the accompanying drawings. The functional modules can be implemented in hardware form, can be implemented in software form, or can be implemented in combination with hardware and software modules. Specifically, the steps of the method embodiments in the embodiments of the present application can be completed by hardware integrated logic circuits in the processor and / or software form instructions. The steps of the method disclosed in the embodiments of the present application can be directly embodied as a hardware coding processor for execution, or can be completed by a combination of hardware and software modules in the coding processor. Optionally, the software module can be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory, and completes the steps in the above method embodiments in combination with its hardware.

[0111] See also Figure 8 The battery pack of the embodiment of the present application includes a processor 401, a memory 402 and a computer program, wherein the computer program is stored in the memory 402 and executed by the processor 401, and the computer program includes instructions for executing the calibration method of any of the above embodiments.

[0112] See also Fig. 9 The embodiment of the present application also provides a computer-readable storage medium 600 on which a computer program 610 is stored. When the computer program 610 is executed by a processor 620, the steps of the calibration method of any of the above-mentioned embodiments are implemented. For the sake of brevity, they are not repeated here.

[0113] In the description of this specification, the descriptions with reference to the terms "certain embodiments", "in an example", "exemplarily", etc., mean that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0114] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0115] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A calibration method, characterized in that: For a battery pack, the method comprises: When the battery pack is in a standby state, obtaining a current voltage of the battery pack; Determine and calibrate the remaining power based on the current voltage, wherein in the standby state, there is a preset mapping relationship between the voltage and the remaining power of the battery pack; When the calibrated remaining power is within a preset power range, estimating a power reduction rate based on the calibrated remaining power; The target remaining power is displayed based on the power decrease speed and the initial remaining power, where the initial remaining power is calculated based on the current of the battery pack.

2. The calibration method according to claim 1, characterized in that: When the current of the battery pack is less than a preset current threshold, it is determined that the battery pack is in the standby state.

3. The calibration method according to claim 1, characterized in that: The current voltage is the output voltage of the battery pack; or, the battery pack includes a plurality of battery cells, the plurality of battery cells are connected in parallel, and the current voltage is the voltage of any of the battery cells.

4. The calibration method according to claim 1, characterized in that: The preset power range includes multiple ones, and there is a positive correlation between the remaining power in the preset power range and the voltage of the battery pack.

5. The calibration method according to claim 1 or 4, characterized in that: The preset power range includes a first preset power range and a second preset power range, the first preset power range is [0, 30%], and the second preset power range is [55%, 65%].

6. The calibration method according to claim 1, characterized in that: The method further comprises: In a case where the calibrated remaining power is outside the preset power range, a target remaining power is displayed based on the initial remaining power.

7. The calibration method according to claim 1, characterized in that: The estimating the rate of power reduction based on the calibrated remaining power includes: Based on the calibrated remaining power and the detection current, the power reduction speed is estimated, and the detection current is determined based on at least one of the current current of the battery pack and the preset standby current.

8. The calibration method according to claim 7, characterized in that: The estimating the rate of power reduction based on the calibrated remaining power and the detected current includes: Based on the calibration remaining power and the detection current, determining the time duration for the calibration remaining power to drop to the minimum power of the preset power range; The power reduction speed is calculated based on the duration and the initial remaining power.

9. The calibration method according to claim 1, characterized in that: The method further comprises: When the battery pack is in an operating state, a target remaining power is displayed based on the initial remaining power, and a current of the battery pack in the operating state is greater than a current in the standby state.

10. A calibration device, characterized in that: For a battery pack, the device comprises: An acquisition module, used for acquiring a current voltage of the battery pack when the battery pack is in a standby state; A determination module, configured to determine and calibrate the remaining power based on the current voltage, wherein in the standby state, there is a preset mapping relationship between the voltage and the remaining power of the battery pack; An estimation module, configured to estimate a rate of power reduction based on the calibration remaining power when the calibration remaining power is within a preset power range; The display module is used to display the target remaining power based on the power decrease speed and the initial remaining power, and the initial remaining power is calculated based on the current of the battery pack.

11. A battery pack, characterized in that: include: Processor, memory; and A computer program, wherein the computer program is stored in the memory and executed by the processor, and the computer program includes instructions for executing the calibration method according to any one of claims 1 to 9.

12. A non-volatile computer-readable storage medium, characterized in that: The method comprises a computer program, and when the computer program is executed by a processor, the processor is caused to execute the calibration method according to any one of claims 1 to 9.

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