Battery management method and device, storage medium, electronic device, and vehicle

Abstract

The application provides a battery management method and device, a storage medium, an electronic device and a vehicle. The battery has a plurality of battery cells for supplying power to the vehicle. The battery management method comprises: a battery cell voltage sampling step of sampling the voltage of each battery cell in the battery; a fault determination step of determining whether the sampling of the battery cell voltage has failed; a residual capacity calculation step of calculating the residual capacity of the battery; a residual capacity comparison step of comparing the residual capacity of the battery with a specified capacity value; and a current limitation step of determining whether to limit the discharge current or the charging current of the battery according to the comparison result of the residual capacity comparison step when it is determined that the sampling of the battery cell voltage has failed.

Description

Technical Field

[0001] This invention relates to battery management methods, battery management devices, storage media, electronic devices, and vehicles, and more particularly to battery management methods, battery management devices, storage media, electronic devices, and vehicles for judging faults that occur when sampling the cell voltage of a battery. Background Technology

[0002] In recent years, the use of battery-powered electric vehicles has become increasingly widespread. The voltage of the batteries supplying these vehicles is not constant. As the battery is charged, its voltage gradually increases; as it is discharged, its voltage gradually decreases. Both excessively high and low voltages can damage the battery and even lead to safety accidents. Therefore, it is essential to understand the voltage of the battery and its constituent cells.

[0003] In existing technologies, voltage sampling is typically performed on each battery cell to determine its voltage. However, if a sampling failure occurs, the battery's discharge or recharging process is usually stopped to prevent damage.

[0004] However, not all detected cell voltage sampling faults necessitate stopping battery discharge or recharging. This is because the battery can still discharge when its charge level is high, and it can still recharge when its charge level is low. Therefore, existing technology sometimes incorrectly limits the battery's discharge or recharge capabilities, resulting in a shorter driving range. Summary of the Invention

[0005] In view of the above-mentioned technical problems, the present invention provides a battery management method, a battery management device, a storage medium, an electronic device, and a vehicle, which avoids the shortening of the vehicle's driving range due to incorrect limitation of the battery's discharge or recharge capabilities when a fault occurs in the sampling of the battery cell voltage.

[0006] A first aspect of the present invention provides a battery management method, the battery having a plurality of cells for supplying power to a vehicle, the battery management method comprising: a cell voltage sampling step for sampling the voltage of each cell in the battery; a fault determination step for determining whether a fault has occurred in the sampling of the cell voltage; a remaining capacity calculation step for calculating the remaining capacity of the battery; a remaining capacity comparison step for comparing the remaining capacity of the battery with a predetermined capacity value; and a current limiting step for determining whether to limit the discharge current or charging current of the battery based on the comparison result of the remaining capacity comparison step if a fault has occurred in the sampling of the cell voltage.

[0007] By employing the battery management method of the first aspect, the present invention can achieve the following technical effects: even if the sampling of the cell voltage fails, it can ensure the vehicle can continue to drive to the maximum extent while preventing damage to the battery from the continued driving of the vehicle.

[0008] In some embodiments, when the battery is in a discharging state, the predetermined charge value is set to a first charge value. In the current limiting step, based on the comparison result of the remaining charge comparison step, it is determined whether to limit the discharge current of the battery. When the battery is in a charging state, the predetermined charge value is set to a second charge value that is greater than the first charge value. In the current limiting step, based on the comparison result of the remaining charge comparison step, it is determined whether to limit the charging current of the battery.

[0009] In this embodiment, even if the sampling of the cell voltage fails, the vehicle can continue to drive to the maximum extent possible while preventing the battery from overcharging or over-discharging.

[0010] In some embodiments, the battery management method further includes a sampling fault notification step: when it is determined that a sampling fault has occurred in the cell voltage sampling, notifying the vehicle that a sampling fault has occurred in the cell voltage sampling.

[0011] In this embodiment of the application, the battery management method includes a sampling fault notification step that notifies the vehicle driver that a sampling fault has occurred in the cell voltage sampling. This enables the vehicle driver to be aware of the situation where a sampling fault has occurred in the cell voltage sampling.

[0012] In some embodiments, during the current limiting step, if the remaining charge of the battery is greater than the first charge value, the discharge current of the battery is not limited.

[0013] In this embodiment of the application, the discharge current of the battery is not limited when the remaining charge of the battery is greater than the first charge value, so that the vehicle can continue to drive in its original state even if the sampling of the cell voltage fails.

[0014] In some embodiments, during the current limiting step, when the remaining charge of the battery is below the first charge value, the discharge current of the battery is limited to be less than the discharge current in the state where no sampling fault has occurred.

[0015] In this embodiment, even if the sampling of the cell voltage fails, the vehicle can continue to drive to the maximum extent possible while preventing damage to the battery from continued driving.

[0016] In some embodiments, the battery management method further includes: a pre-undervoltage judgment step of determining whether the minimum value among the sampled valid cell voltage values ​​is below the cell undervoltage threshold; comparing the remaining battery capacity with a third capacity value that is less than the first capacity value in the remaining capacity comparison step; and limiting the discharge current of the battery to stop the battery from discharging when the minimum value among the valid cell voltage values ​​is below the cell undervoltage threshold or the remaining battery capacity is below the third capacity value in the current limiting step.

[0017] In this embodiment, the vehicle can be stopped when the minimum effective cell voltage value is below the cell undervoltage threshold or the remaining battery charge is below the third charge value, thus preventing damage to the battery from continued driving.

[0018] In some embodiments, during the current limiting step, the charging current of the battery is not limited if the remaining charge of the battery is less than a second charge value.

[0019] In this embodiment, the charging current of the battery is not limited when the remaining battery power is less than the second power value, so that the battery can continue to be charged even if the sampling of the cell voltage fails.

[0020] In some embodiments, there is also a pre-overvoltage judgment step of determining whether the maximum value among the valid cell voltage values ​​obtained by sampling is above the cell full charge voltage threshold. In the current limiting step, if the maximum value among the valid cell voltage values ​​is above the cell full charge voltage threshold or the remaining capacity of the battery is above the second capacity value, the charging current of the battery is limited to stop the battery from charging.

[0021] In this embodiment, when the maximum value among the effective cell voltage values ​​is above the cell full charge voltage threshold or the remaining battery capacity is above the second capacity value, the charging current of the battery is limited. By stopping the charging of the battery, damage to the battery due to overcharging can be prevented.

[0022] A second aspect of the present invention provides a battery management device, wherein the battery has a plurality of cells for supplying power to a vehicle, the battery management device comprising: a cell voltage acquisition module for acquiring cell voltages obtained by sampling the voltages of each cell in the battery; a fault judgment module for determining whether a fault has occurred in the sampling of the cell voltages; a remaining capacity calculation module for calculating the remaining capacity of the battery; a remaining capacity comparison module for comparing the remaining capacity of the battery with a predetermined capacity value; and a current limiting module for determining whether to limit the discharge current or charging current of the battery based on the comparison result of the remaining capacity comparison module when a fault has occurred in the sampling of the cell voltages.

[0023] In this embodiment of the application, even if the sampling of the cell voltage fails, it is possible to ensure the vehicle can continue to drive to the maximum extent while preventing damage to the battery from the continued driving of the vehicle.

[0024] In some embodiments, when the battery is in a discharging state, the predetermined charge value is set to a first charge value, and the current limiting module determines whether to limit the battery's discharge current based on the comparison result of the remaining charge comparison step. When the battery is in a charging state, the predetermined charge value is set to a second charge value that is greater than the first charge value, and the current limiting module determines whether to limit the battery's charging current based on the comparison result of the remaining charge comparison step.

[0025] In this embodiment of the application, even if the sampling of the cell voltage fails, it is possible to ensure the vehicle can continue to drive to the maximum extent while preventing the battery from overcharging or over-discharging while the vehicle continues to drive.

[0026] In some embodiments, the battery management device further includes a sampling fault notification module that notifies the vehicle that a sampling fault has occurred when it is determined that a sampling fault has occurred in the cell voltage sampling.

[0027] In this embodiment, the vehicle driver can be informed that a fault has occurred in the sampling of the battery cell voltage.

[0028] In some embodiments, the current limiting module does not limit the discharge current of the battery when the remaining charge of the battery is greater than a first charge value.

[0029] In this embodiment of the application, even if the sampling of the cell voltage fails, the vehicle can still maintain its original state of operation.

[0030] In some embodiments, when the remaining charge of the battery is below a first charge value, the current limiting module limits the discharge current of the battery to be less than the discharge current in the state where no sampling fault has occurred.

[0031] In this embodiment of the application, even if the sampling of the cell voltage fails, it is possible to ensure the vehicle can continue to drive to the maximum extent while preventing damage to the battery from the continued driving of the vehicle.

[0032] In some embodiments, the battery management device further includes a pre-undervoltage judgment module for determining whether the minimum value among the valid cell voltage values ​​obtained by sampling is below the cell undervoltage threshold. The remaining power comparison module compares the remaining power of the battery with a third power value that is less than the first power value. The current limiting module limits the discharge current of the battery to stop the battery from discharging when the minimum value among the valid cell voltage values ​​is below the cell undervoltage threshold or the remaining power of the battery is below the third power value.

[0033] In this embodiment, the vehicle can be stopped from moving to prevent damage to the battery from continued driving.

[0034] In some embodiments, the current limiting module does not limit the charging current of the battery when the remaining charge of the battery is less than a second charge value.

[0035] In this embodiment of the application, the battery can continue to be charged even if the sampling of the cell voltage fails.

[0036] In some embodiments, the battery management device further includes a pre-overvoltage judgment module that determines whether the maximum value among the valid cell voltage values ​​obtained by sampling is above the cell full charge voltage threshold. The current limiting module limits the charging current of the battery to stop charging the battery when the maximum value among the valid cell voltage values ​​is above the cell full charge voltage threshold or the remaining capacity of the battery is above the second capacity value.

[0037] In this embodiment of the application, by stopping the charging of the battery, damage to the battery due to overcharging can be prevented.

[0038] A third aspect of the present invention provides a storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the battery management method described in the first aspect.

[0039] A fourth aspect of the present invention provides an electronic device, comprising: a processor, a storage medium as described in the third aspect, and a bus, wherein the processor and the storage medium communicate with each other via the bus.

[0040] A fifth aspect of the invention provides a vehicle, comprising: a battery for supplying power to the vehicle and a battery management device as described in the second aspect.

[0041] By employing any one of the storage medium of the third aspect, the electronic device of the fourth aspect, and the vehicle of the fifth aspect, the present invention can achieve the following technical effect: even if the sampling of the cell voltage fails, it can ensure the vehicle continues to run to the maximum extent while preventing damage to the battery from the continued running of the vehicle. Attached Figure Description

[0042] The accompanying drawings, which are provided to further illustrate this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application.

[0043] Figure 1 This is a schematic diagram of the cell voltage sampling unit sampling the voltage of each cell in the battery.

[0044] Figure 2 This is a schematic diagram showing the connection between the battery management system and the cell voltage sampling unit.

[0045] Figure 3 This is a schematic diagram illustrating the interaction between the battery management system and the vehicle control system.

[0046] Figure 4 This is a flowchart of the battery management method of the present invention in a discharged state.

[0047] Figure 5 This is a block diagram illustrating the battery management device of Embodiment 1.

[0048] Figure 6 This is a flowchart illustrating the battery management method of Example 2.

[0049] Figure 7 This is a flowchart illustrating the battery management method of Example 3.

[0050] Figure 8 This is a flowchart illustrating the battery management method of Example 4.

[0051] Figure 9 This is a block diagram illustrating the battery management device of Embodiment 4.

[0052] Figure 10 This is a schematic diagram illustrating the electronic device of Embodiment 5.

[0053] Figure 11 This is a block diagram representing the vehicle of Embodiment 5. Specific Implementation

[0054] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0055] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0056] In this application, "multiple" means two or more (including two).

[0057] In this specification, "below...value" includes both cases of "equal to...value" and "less than...value". For example, the previously mentioned "below the first charge value" includes both cases of "equal to the first charge value" and "less than the first charge value". Similarly, "above...value" includes both cases of "equal to...value" and "greater than...value". For example, the previously mentioned "above the full charge voltage threshold of the battery cell" includes both cases of "equal to the full charge voltage threshold of the battery cell" and "greater than the full charge voltage threshold of the battery cell".

[0058] Example 1

[0059] During the operation of an electric vehicle, whether the battery with multiple cells is in a discharging or charging state, the voltage of each cell needs to be monitored and sampled in real time. This is necessary for effective battery management, to prevent cells from being overcharged or over-discharged, and thus to ensure battery safety and lifespan.

[0060] Figure 1 This is a schematic diagram of the cell voltage sampling unit sampling the voltage of each cell in the battery. Figure 2 This is a schematic diagram showing the connection between the battery management system and the cell voltage sampling unit.

[0061] Figure 1 The battery 12 includes n cells (i.e., cell 1, cell 2, ..., cell n) for powering the vehicle, where n is a natural number greater than 2.

[0062] like Figure 1 As shown, the cell voltage sampling unit 11 includes one sampling chip and n sampling circuits. The n sampling circuits are set up one-to-one with the n cells, and the sampling chip is used to sample the voltage of each cell.

[0063] When the cell voltage sampling unit 11 samples the voltage of each cell of the battery 12, the sampling faults described below ①-④ may occur.

[0064] ① Unreliable cell voltage fault

[0065] The so-called unreliable cell voltage fault refers to a situation where the sum of the voltages of each cell sampled by the sampling chip differs too much from the voltage supplied to the sampling chip and sampled by the sampling chip.

[0066] For example in Figure 1 In this diagram, n battery cells are connected in series. Assume the voltages sampled from cell 1, cell 2, ..., cell n are v1, v2, ..., vn, respectively, and the sum of these voltages is v1 + v2 + ... + vn = Vh. Furthermore, assume the voltage supplied to the sampling chip and sampled by the sampling chip is Vx. Under normal sampling conditions, Vh and Vx should be the same or very close. If the difference between them exceeds a specified value (or a specified range), then the sampling of the cell voltage is considered to have failed ① (i.e., the cell voltage is unreliable). This specified value (or specified range) can be set according to actual needs and is not necessarily fixed.

[0067] ② Cell voltage over-limit fault

[0068] The so-called cell voltage over-limit fault refers to a situation where the voltage value of one or more cells is outside the reasonable range.

[0069] For example, suppose the reasonable range for the cell voltage is 0.5V-4.8V. If one or more of the values ​​of v1, v2, ..., vn are less than 0.5V or greater than 4.8V, then the cell voltage is considered to be outside the reasonable range, and a cell voltage over-limit fault has occurred.

[0070] ③ Incomplete cell voltage data

[0071] Incomplete cell voltage data refers to a situation where the battery management system has not received the voltage values ​​of all cells (i.e., one or more cell voltage values ​​are missing).

[0072] For example in Figure 2In this system, there are n battery cells. The battery management system 13 should receive n cell voltage values ​​(v1, v2, ..., vn) corresponding to these n cells (cell 1, cell 2, ..., cell n) from the cell voltage sampling unit 11. If the battery management system 13 fails to receive one or more of these n cell voltage values ​​from the cell voltage sampling unit 11, it is considered that a sampling fault of incomplete cell voltage data has occurred.

[0073] ④ Sampling chip voltage over-limit fault

[0074] The so-called sampling chip voltage over-limit fault refers to a situation where the voltage Vx supplied to the sampling chip and sampled by the sampling chip exceeds the reasonable range.

[0075] When the battery management system 13 receives the cell voltage value from the cell voltage sampling unit 11, it can determine whether the sampling of the cell voltage has experienced the sampling fault described above.

[0076] Figure 3 This is a schematic diagram illustrating the interaction between the battery management system and the vehicle control system. Figure 3 This indicates the discharge state of battery 12, where DC power is supplied from n cells (cell 1, cell 2, ..., cell n) to bidirectional DC / AC converter 15. This DC power is converted into three-phase AC power by bidirectional DC / AC converter 15 and then supplied to the vehicle's motor 16 to enable the vehicle to move. In the battery's discharge state, motor 16 rotates forward.

[0077] When the vehicle reverses the motor 16 due to going downhill or braking, it can charge the battery 12. In the charging state (return charging state) of the battery, the AC power generated by the reverse rotation of the motor 16 is converted into DC power by the bidirectional DC / AC converter 15 and supplied to the battery 12 to charge the battery 12.

[0078] When the battery management system 13 determines that a sampling fault has occurred in the cell voltage sampling as described above, based on the cell voltage value obtained from the cell voltage sampling unit 11, it can limit the battery's discharge current and charging current, and notify the vehicle control system 14 of the sampling fault via the vehicle communication bus. The vehicle control system 14, based on the feedback from the battery management system 13, controls the vehicle display screen 17 to display a fault light to inform the driver that a sampling fault has occurred in the cell voltage sampling, and controls the forward and reverse rotation speeds of the motor 16 to control the vehicle speed and braking torque.

[0079] Figure 4 This is a flowchart of the battery management method of the present invention in a discharged state.

[0080] First, in step S1, the voltage of each cell in battery 12 is sampled to obtain the voltage of each cell. Specifically, as follows... Figure 1 , 2 As shown, the cell voltage sampling unit 11 samples the voltage of each cell in the battery 12 and sends the sampled cell voltage values ​​to the battery management system 13.

[0081] Then, in step S2, it is determined whether a sampling fault has occurred in the sampling of the cell voltage. The method for determining the sampling fault can refer to the previous explanations of sampling faults ① to ④. For example, if the difference between the sum Vh of the cell voltages v1, v2, ..., vn corresponding to cell 1, cell 2, ..., cell n, and the voltage Vx supplied to the sampling chip and sampled by the sampling chip exceeds a specified value (i.e., exceeds a specified range), then it is determined that the sampling of the cell voltage has experienced fault ① (i.e., an unreliable cell voltage fault).

[0082] If a sampling failure is determined in step S2, the vehicle is notified of the sampling failure in step S3 so that the driver is aware of the situation. For example, the notification could be sent to the vehicle display screen 17 (e.g., ...). Figure 3 The warning light (as shown) is displayed.

[0083] If it is determined in step S2 that there is no sampling failure in the sampling of the cell voltage, then this process ends.

[0084] In step S4, the remaining battery charge is compared with the charge value A (corresponding to the "first charge value" in the invention description). The remaining battery charge refers to the battery's state of charge (SOC), that is, how much charge the battery can currently discharge. The charge value A can be set to, for example, 30% of the battery's full charge capacity, but is not limited to 30% and can be other values.

[0085] Before comparing the remaining battery capacity with the capacity value A, the remaining battery capacity can be calculated based on the integral values ​​of the charging current and discharging current. In this embodiment, the battery is in a discharging state, therefore the remaining battery capacity is calculated based on the integral value of the battery's discharging current.

[0086] The calculation of the battery's remaining capacity is performed independently from the sampling of the cell voltage. Therefore, even if a sampling failure occurs during the sampling of the cell voltage, it will not affect the accuracy of the calculation of the battery's remaining capacity.

[0087] Since the method for calculating the remaining battery capacity is existing technology, it will not be described in detail in this manual.

[0088] In step S4, if it is determined that the remaining battery charge is greater than the charge value A, the battery discharge current is not limited, and the vehicle continues to drive in its original state, thus ending the process.

[0089] In step S4, if it is determined that the remaining battery charge is below charge value A, then step S5 is executed. In step S5, it is determined whether the remaining battery charge is below charge value B (corresponding to the "third charge value" in the invention description), or whether the cell voltage sampled in step S1 has a pre-undervoltage condition.

[0090] In this case, the power value B is less than the power value A. For example, it can be set to 10% of the power when the battery is fully charged, but it is not limited to 10% of the power when the battery is fully charged. It can also be other values.

[0091] The term "pre-undervoltage" refers to the fact that the smallest cell voltage value among the valid cell voltage values ​​obtained from sampling in step S1 is below the cell undervoltage threshold.

[0092] A valid cell voltage value refers to one of the cell voltage values ​​v1, v2, ... vn obtained in step S1 that falls within the reasonable range (0.5V-4.8V). Cell voltage values ​​outside the reasonable range (0.5V-4.8V) are not valid values. For information on the reasonable range (0.5V-4.8V), please refer to the explanation regarding cell voltage over-limit fault ②.

[0093] The cell undervoltage threshold mentioned above is the cell voltage value when the battery has zero remaining charge in a non-discharged and non-charged state, for example, 2.8V. When the cell voltage is below this cell undervoltage threshold (2.8V), the cell may be damaged.

[0094] If the minimum value among the valid cell voltage values ​​obtained by sampling in step S1 is below the aforementioned cell undervoltage threshold, then it is determined that the cell voltage obtained by sampling in step S1 has a pre-undervoltage condition.

[0095] In step S5, if it is determined that the remaining battery charge is below the charge value B, or if the cell voltage sampled in step S1 has a pre-undervoltage condition, then step S6 is executed. In step S6, the battery discharge current is reduced to 0 (i.e., the vehicle is stopped) to prevent further battery discharge from damaging the battery.

[0096] As described above, in step S6, in order to prevent the battery from being damaged by continued discharge, the discharge current is made zero as long as one of the following two conditions I and II is met.

[0097] I. The remaining battery power is below level B;

[0098] II. The cell voltage sampled in step S1 has a pre-undervoltage condition.

[0099] The reason why the discharge current is zero as long as either of the above two conditions I or II is met is as follows.

[0100] During charging and discharging, the remaining battery capacity is calculated based on the charging and discharging current, and the battery cell itself exhibits polarization. During charging, the cell voltage will appear artificially high due to the current; similarly, during discharging, the cell voltage will appear artificially low. Therefore, even though the remaining battery capacity has not yet decreased to 0% during discharging, cell polarization caused by the discharging current can result in a cell voltage below the cell undervoltage threshold (2.8V). To prevent battery damage caused by continued discharging when the cell voltage is below the cell undervoltage threshold, in addition to setting the discharging current to 0 based on condition I above, condition II above is also used to set the discharging current to 0 to prevent cell damage.

[0101] In step S5, if it is determined that the remaining battery charge is greater than the charge value B, and the cell voltage sampled in step S1 does not have a pre-undervoltage condition, then step S7 is executed. In step S7, the battery discharge current is limited (i.e., the battery discharge current is reduced) to make the discharge current less than the discharge current under the condition that no sampling fault occurred.

[0102] Compared to the discharge current value under conditions where no sampling failure occurred, the reduced discharge current value due to limitations can be a specified value. For example, this specified value could be 60A or the minimum discharge current value of the battery.

[0103] The reduced discharge current value due to limitations can also be a variable value. For example, as the remaining battery charge decreases, the closer it gets to the charge value B, the smaller the discharge current value becomes; or, the closer the sampled effective cell voltage value is to the cell undervoltage threshold, the smaller the discharge current value becomes.

[0104] By employing the battery management method described above, this invention can ensure the vehicle can continue driving to the maximum extent possible while preventing damage to the battery from continued driving, even in the event of a failure in the sampling of the cell voltage.

[0105] exist Figure 4 In the flowchart of the battery management method shown, step S3 is performed between steps S2 and S4. However, it is not limited to this; step S3 can also be performed simultaneously with any of steps S4, S5, S6, and S7. That is, as long as it is determined in step S2 that a fault has occurred in the sampling of the cell voltage, the vehicle can be notified of the fault at any step or time after step S2.

[0106] Figure 5 This is a block diagram illustrating the battery management device 50 of Embodiment 1.

[0107] The battery management device 50 includes: a cell voltage acquisition module 51 for acquiring cell voltages obtained by sampling the voltages of each cell in the battery; a fault judgment module 52 for determining whether a cell voltage sampling failure has occurred; a remaining capacity calculation module 53 for calculating the remaining capacity of the battery; a remaining capacity comparison module 54 for comparing the remaining capacity of the battery with a specified capacity value; a current limiting module 55 for determining whether to limit the battery discharge current based on the comparison result of the remaining capacity comparison module when a cell voltage sampling failure is detected; a sampling fault notification module 56 for notifying the vehicle that a cell voltage sampling failure has occurred when a cell voltage sampling failure is detected; and a pre-undervoltage judgment module 57 for determining whether the minimum value among the valid cell voltage values ​​obtained by sampling is below a cell undervoltage threshold.

[0108] Example 2

[0109] Figure 6 This is a flowchart illustrating the battery management method of Example 2 of Example 1.

[0110] exist Figure 4 The flowchart of the battery management method in Embodiment 1 shows a step S3 in which a fault is detected in the sampling of the vehicle's battery cell voltage. However, step S3 is not essential for the battery management method of the present invention. Figure 6 This is a flowchart indicating the battery management method with step S3 omitted.

[0111] In this embodiment 2 Figure 6 Steps S1, S2, S4-S7 and Figure 4 Steps S1, S2, and S4-S7 are the same, so their explanations are omitted here.

[0112] This invention employs Figure 6 The battery management method shown can achieve the following technical effects: even if the sampling of the cell voltage fails, it can ensure the vehicle can continue to run to the maximum extent while preventing damage to the battery from the continued driving of the vehicle.

[0113] The battery management device 50 of Example 1 is capable of... Figure 6 The battery management method shown omits the sampling fault notification module 56 accordingly. In this case, the following technical effect can still be achieved: even if a sampling fault occurs in the cell voltage, the vehicle can continue to operate to the maximum extent possible while preventing damage to the battery from continued operation.

[0114] Example 3

[0115] Figure 7 This is a flowchart illustrating the battery management method of Example 3.

[0116] Figure 7 The battery management method shown is compared to Figure 4 Step S3 has been omitted and replaced with step S71. Figure 4 Steps S5-S7 in the process.

[0117] Specifically, in this embodiment 3, in step S4, the remaining battery charge is compared with the charge value A. If it is determined that the remaining battery charge is greater than the charge value A, the battery discharge current is not limited, allowing the vehicle to continue driving in its original state.

[0118] In step S4, if it is determined that the remaining battery charge is below charge value A, step S71 is executed. In step S71, the battery discharge current is limited to be less than the discharge current under conditions where no sampling fault has occurred.

[0119] This invention employs Figure 7 The battery management method shown can achieve the following technical effect: in the event of a failure in the sampling of the cell voltage, compared with the case where the vehicle continues to drive in its original state without limiting the discharge current of the battery, it can prevent damage to the battery from the continued driving of the vehicle.

[0120] The battery management device 50 of Example 1 is capable of... Figure 7 The battery management method shown omits the sampling fault notification module 56 and the pre-undervoltage judgment module 57 accordingly. In this case, the following technical effect can still be achieved: when a cell voltage sampling failure occurs, compared to continuing to drive the vehicle without limiting the battery discharge current, it can prevent damage to the battery from continued driving.

[0121] Example 4

[0122] Figure 8 This is a flowchart of the battery management method of the present invention in the charging (recharging) state.

[0123] First, in step S1, the voltage of each cell in battery 12 is sampled to obtain the cell voltage of each cell. Specifically, as follows... Figure 1 , 2 As shown, the cell voltage sampling unit 11 samples the voltage of each cell in the battery 12 and sends the sampled cell voltage to the battery management system 13.

[0124] Then, in step S2, it is determined whether a sampling fault has occurred in the sampling of the cell voltage. The method for determining the sampling fault is the same as in Example 1, and its detailed description is omitted here.

[0125] If a sampling failure is determined in step S2, the vehicle is notified of the sampling failure in step S3 so that the driver is aware of the situation. Then, step S84 is executed.

[0126] If it is determined in step S2 that there is no sampling failure in the sampling of the cell voltage, then this process ends.

[0127] In step S84, it is determined whether the remaining charge of the battery is greater than or equal to the charge value C (corresponding to the "second charge value" in the invention) or whether the cell voltage sampled in step S1 has been over-voltaged.

[0128] Among them, the power value C is greater than the power value A. For example, it can be set to 80% of the power when the battery is fully charged, but it is not limited to 80% of the power when the battery is fully charged. It can also be other values.

[0129] The term "pre-overvoltage" refers to the situation where the largest cell voltage value among the cell voltage values ​​v1, v2, ... vn obtained in step S1 is above the cell overvoltage threshold. Here, the cell overvoltage threshold is the cell voltage value when the battery is fully charged, for example, 3.7V. When the cell voltage rises above this cell overvoltage threshold (3.7V), the cell may be damaged.

[0130] If vn is the maximum value among the effective cell voltage values ​​v1, v2, ... vn obtained by sampling in step S1, and the cell voltage value vn is above the cell overvoltage threshold mentioned above, then it is determined that the cell voltage obtained by sampling in step S1 has pre-overvoltage.

[0131] In step S84, if it is determined that the remaining battery capacity is above the capacity value C, or if the cell voltage sampled in step S1 has pre-overvoltage, then step S85 is executed. In step S85, the battery charging current (recharge current) is limited to 0 to prevent damage to the battery from recharging.

[0132] As described above, in step S84, in order to prevent the battery from being damaged by continued recharging, the charging current of the battery is made to be 0 as long as one of the following two conditions III and IV is met.

[0133] III. The remaining battery capacity is above the capacity value C;

[0134] IV. The cell voltage sampled in step S1 has a pre-overvoltage.

[0135] The reason why the charging current of the battery is 0 as long as either of the above two conditions III or IV is met is as follows.

[0136] During charging and discharging, the remaining battery capacity is calculated based on the charging and discharging current, and the battery cell itself exhibits polarization. During charging, the cell voltage will artificially inflate due to the presence of current. Therefore, even though the battery's remaining capacity has not yet reached 100% during charging, the cell voltage may exceed the cell overvoltage threshold (3.7V) due to cell polarization caused by the charging current. To avoid battery damage caused by continuing charging when the cell voltage exceeds the cell overvoltage threshold, in addition to setting the charging current to 0 based on condition III above, condition IV above is also used to set the charging current to 0 to prevent cell damage.

[0137] In step S84, if it is determined that the remaining battery capacity is less than the capacity value C, and the cell voltage sampled in step S1 has not been over-voltaged, then the charging current is not limited, and the process ends.

[0138] By employing the battery management method described above, this invention can ensure the vehicle can continue to operate to the maximum extent possible while preventing damage to the battery from recharging, even in the event of a failure in the sampling of the cell voltage.

[0139] Figure 9 This is a block diagram illustrating the battery management device 90 of Embodiment 4.

[0140] The battery management device 90 includes: a cell voltage acquisition module 51 for acquiring cell voltages obtained by sampling the voltages of each cell in the battery; a fault judgment module 52 for determining whether a cell voltage sampling failure has occurred; a remaining capacity calculation module 53 for calculating the remaining capacity of the battery; a remaining capacity comparison module 54 for comparing the remaining capacity of the battery with a specified capacity value; a current limiting module 55 for determining whether to limit the battery discharge current based on the comparison result of the remaining capacity comparison module when a cell voltage sampling failure is detected; a sampling fault notification module 56 for notifying the vehicle that a cell voltage sampling failure has occurred when a cell voltage sampling failure is detected; and a pre-overvoltage judgment module 97 for determining whether the maximum value among the valid cell voltage values ​​obtained by sampling is above a cell overvoltage threshold.

[0141] By employing the aforementioned battery management device, the present invention can also achieve the following technical effects: even if the sampling of the cell voltage fails, it can ensure the vehicle continues to operate to the maximum extent while preventing damage to the battery from recharging.

[0142] Example 5

[0143] Figure 10 This is a schematic diagram of the electronic device in this embodiment. (As shown...) Figure 6 As shown, the electronic device 100 includes a processor 101, a memory 102, and a bus 103. The processor 101 and the memory 102 communicate with each other via the bus 103. The processor 101 is used to call program instructions in the memory 102 to execute the battery management methods provided in the above embodiments.

[0144] Processor 101 can be an integrated circuit chip with signal processing capabilities. Processor 101 can be a general-purpose processor, including a central processing unit (CPU), a network processor, etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0145] The memory 102 may include, but is not limited to, random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable read-only memory (EPROM), electrically erasable read-only memory (EEPROM), etc.

[0146] This embodiment provides a non-transitory computer-readable storage medium that stores computer instructions. When executed by a processor, the computer instructions cause the processor to perform the battery management methods provided in the above embodiments.

[0147] Figure 11 This is a block diagram of an electric vehicle provided as an embodiment of this application. Figure 11 As shown, the electric vehicle includes a battery for supplying power to the electric vehicle and a battery management device provided in the above embodiments for managing the battery.

[0148] By employing the aforementioned storage medium, electronic device, and vehicle, the present invention achieves the following technical effects: even in the event of a failure in the sampling of the battery cell voltage, it can ensure the vehicle continues to operate to the maximum extent possible while preventing damage to the battery from recharging.

[0149] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features. However, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A battery management method, characterized in that, The battery has multiple cells for supplying power to the vehicle, and the battery management method includes: A cell voltage sampling step that samples the voltage of each cell in the battery; Fault diagnosis steps to determine whether a sampling failure has occurred in the cell voltage; The remaining power calculation steps for calculating the remaining power of the battery; A remaining capacity comparison step that compares the remaining capacity of the battery with a predetermined capacity value; and, If a fault is detected in the sampling of the cell voltage, a current limiting step is performed to determine whether to limit the discharge current or charging current of the battery, based on the comparison result of the remaining power comparison step.

2. The battery management method as described in claim 1, characterized in that, When the battery is in a discharging state, the specified charge value is set to a first charge value. In the current limiting step, based on the comparison result of the remaining charge comparison step, it is determined whether to limit the discharge current of the battery. When the battery is in a charging state, the specified charge value is set to a second charge value that is greater than the first charge value. In the current limiting step, based on the comparison result of the remaining charge comparison step, it is determined whether to limit the charging current of the battery.

3. The battery management method as described in claim 2, characterized in that, Also includes: In the event that a sampling failure has occurred in the cell voltage sampling, a sampling failure notification step is performed to notify the vehicle that a sampling failure has occurred in the cell voltage sampling.

4. The battery management method as described in claim 2 or 3, characterized in that, In the current limiting step, if the remaining charge of the battery is greater than the first charge value, the discharge current of the battery is not limited.

5. The battery management method according to any one of claims 2-4, characterized in that, In the current limiting step, when the remaining charge of the battery is below the first charge value, the discharge current of the battery is limited so that the discharge current of the battery is less than the discharge current in the state where no sampling fault has occurred.

6. The battery management method according to any one of claims 2-5, characterized in that, The method further includes: The step involves determining whether the minimum value among the valid cell voltage values ​​obtained from sampling is below the cell undervoltage threshold, thus triggering a pre-undervoltage judgment. In the remaining power comparison step, the remaining power of the battery is compared with a third power value that is less than the first power value; In the current limiting step, if the minimum of the effective cell voltage values ​​is below the cell undervoltage threshold or the remaining charge of the battery is below the third charge value, the discharge current of the battery is limited to stop the battery from discharging.

7. The battery management method according to any one of claims 2-6, characterized in that, In the current limiting step, if the remaining charge of the battery is less than the second charge value, the charging current of the battery is not limited.

8. The battery management method according to any one of claims 2-7, characterized in that, The method further includes: The step is to determine whether the maximum value among the valid cell voltage values ​​obtained from the sampling is above the cell full charge voltage threshold for pre-overvoltage judgment. In the current limiting step, if the maximum value among the effective cell voltage values ​​is above the cell full charge voltage threshold or the remaining capacity of the battery is above the second capacity value, the charging current of the battery is limited to stop the battery from charging.

9. A battery management device, characterized in that, The battery has multiple cells for supplying power to the vehicle, and the battery management device includes: A cell voltage acquisition module that obtains the cell voltage by sampling the voltage of each cell in the battery; A fault detection module to determine whether a fault has occurred in the sampling of the cell voltage; A remaining power calculation module for calculating the remaining power of the battery; A remaining power comparison module that compares the remaining power of the battery with a predetermined power value; and, If a fault is detected in the sampling of the cell voltage, the system determines whether to limit the discharge current or the charging current of the battery based on the comparison result of the remaining power comparison module.

10. The battery management device as claimed in claim 9, characterized in that, When the battery is in a discharging state, the specified charge value is set to a first charge value, and the current limiting module determines whether to limit the battery's discharge current based on the comparison result of the remaining charge comparison step. When the battery is in a charging state, the specified charge value is set to a second charge value that is greater than the first charge value. The current limiting module determines whether to limit the charging current of the battery based on the comparison result of the remaining charge comparison step.

11. The battery management device as claimed in claim 10, characterized in that, Also includes: If a sampling failure is detected in the cell voltage sampling, a sampling failure notification module is notified that the sampling of the vehicle's cell voltage has failed.

12. The battery management device as claimed in claim 10 or 11, characterized in that, The current limiting module does not limit the discharge current of the battery when the remaining charge of the battery is greater than the first charge value.

13. The battery management device as claimed in any one of claims 10-12, characterized in that, When the remaining charge of the battery is below the first charge value, the current limiting module limits the discharge current of the battery so that the discharge current of the battery is less than the discharge current in the state where no sampling fault has occurred.

14. The battery management device as claimed in any one of claims 10-13, characterized in that, Also includes: The module determines whether the minimum value among the valid cell voltage values ​​obtained from sampling is below the cell undervoltage threshold. The remaining power comparison module compares the remaining power of the battery with a third power value that is less than the first power value; The current limiting module limits the discharge current of the battery to stop the battery from discharging when the minimum effective cell voltage value is below the cell undervoltage threshold or when the remaining charge of the battery is below the third charge value.

15. The battery management device as claimed in any one of claims 10-14, characterized in that, The current limiting module does not limit the charging current of the battery when the remaining battery power is less than the second power value.

16. The battery management device as claimed in any one of claims 10-15, characterized in that, Also includes: A pre-overvoltage judgment module that determines whether the maximum value among the valid cell voltage values ​​obtained from sampling is above the cell full charge voltage threshold. When the maximum effective cell voltage value is above the cell full charge voltage threshold or the remaining battery capacity is above the second capacity value, the current limiting module limits the charging current of the battery, thereby stopping the battery from charging.

17. A storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, causes the processor to perform the battery management method according to any one of claims 1-8.

18. An electronic device, characterized in that, include: The processor, the storage medium as described in claim 17, and the bus, wherein the processor and the storage medium communicate with each other via the bus.

19. A vehicle, characterized in that, include: A battery for supplying power to a vehicle, and a battery management device as claimed in any one of claims 10-16.

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