Current control method of battery pack

Abstract

The invention relates to a current control method of a battery pack. The method comprises the steps that in the charging and discharging process of a battery pack, target state data of all battery cells in the battery pack are acquired, and the target state data comprise at least one of a voltage value and a temperature value; according to a preset current control curve and the target state data, target reference current of the battery pack is determined, and the current control curve comprises a mapping relation between the state data of the battery cell and the reference current; and performing current control on the battery pack according to a preset current control condition and the target reference current. By adopting the method, the timeliness of current control of the battery pack can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a current control method of a battery pack. BACKGROUND

[0002] With the continuous development of battery technology, battery pack products composed of multiple battery cells have also been introduced. During use, the battery pack product will undergo a charging-discharging-charging cycle. During each repeated charging and discharging process, excessive current will affect the raw materials of the battery cells, thereby shortening the service life of the battery cells and affecting the product quality.

[0003] In the prior art, the charging capacity and discharging capacity are usually controlled to avoid full charging and full discharging of the battery pack, thereby improving the service life of the battery pack. However, this method has the problem of insufficient timeliness of control. SUMMARY

[0004] Therefore, it is necessary to provide a current control method of a battery pack capable of improving the timeliness of current control of the battery pack.

[0005] In a first aspect, the present application provides a current control method of a battery pack, comprising: obtaining target state data of each battery cell in the battery pack during charging and discharging of the battery pack, the target state data comprising at least one of a voltage value and a temperature value; determining a target reference current of the battery pack according to a preset current control curve and the target state data, the current control curve comprising a mapping relationship between the state data of the battery cell and the reference current; and reducing a target current value of the battery pack according to a preset current control condition and the target reference current, the target current value comprising an input current value and / or an output current value of the battery pack, the current control condition being related to the target reference current and the target current value.

[0006] In one embodiment, reducing the target current value of the battery pack according to the preset current control condition and the target reference current comprises: detecting whether the target current value satisfies the current control condition; and if the target current value satisfies the current control condition, reducing the target current value to the target reference current.

[0007] In one embodiment, reducing the current value of the battery pack to the target reference current comprises: generating a current control instruction according to the target reference current, and sending the current control instruction to an inverter corresponding to the battery pack, the current control instruction being used to instruct the inverter to reduce the current value of the battery pack to the target reference current.

[0008] In one embodiment, after sending the current control instruction to the inverter corresponding to the battery pack, the method further comprises: obtaining the current value of the battery pack, and if the current value of the battery pack is greater than the target reference current, controlling the battery pack to stop charging and discharging.

[0009] In one of the embodiments, the current control condition comprises: the target current value is greater than the target reference current, and the duration of the target current value is greater than a time threshold, and / or, the target current value is greater than a current lower threshold.

[0010] In one of the embodiments, the target reference current of the battery pack is determined according to the preset current control curve and the target state data, comprising: determining a first current control curve corresponding to the voltage and a second current control curve corresponding to the temperature in the plurality of current control curves according to the use state of the battery pack, the use state comprising the charging state and the discharging state; determining the first target reference current according to the first current control curve and the voltage value, and determining the second target reference current according to the second current control curve and the temperature value; determining the minimum value of the first target reference current and the second target reference current as the target reference current.

[0011] In one of the embodiments, the first target reference current is determined according to the first current control curve and the voltage value, comprising: in the case of the use state being the charging state, screening out the maximum voltage value in the voltage value, and obtaining the first target reference current corresponding to the maximum voltage value by traversing the first current control curve according to the maximum voltage value; and / or, in the case of the use state being the discharging state, screening out the minimum voltage value in the voltage value, and obtaining the first target reference current corresponding to the minimum voltage value by traversing the first current control curve according to the minimum voltage value.

[0012] In one of the embodiments, the second target reference current is determined according to the second current control curve and the temperature value, comprising: screening out the maximum temperature value in the temperature value; and obtaining the second target reference current corresponding to the maximum temperature value by traversing the second current control curve according to the maximum temperature value.

[0013] In one of the embodiments, the current control curve comprises at least one of: a third current control curve representing the mapping relationship between the current value and the maximum voltage value in each battery cell in the charging state; a fourth current control curve representing the mapping relationship between the current value and the maximum voltage value in each battery cell in the discharging state; a fifth current control curve representing the mapping relationship between the current value and the maximum temperature value in each battery cell in the charging state; and a sixth current control curve representing the mapping relationship between the current value and the maximum temperature value in each battery cell in the discharging state.

[0014] In one of the embodiments, the target current value of the battery pack is reduced according to the preset current control condition and the target reference current, comprising: obtaining the first target reference current of the first battery pack connected in parallel with the battery pack, the current value of the first battery pack satisfying the current control condition; screening out the minimum target reference current from the first target reference current and the target reference current; and reducing the target current value and the first current value of the first battery pack to the minimum target reference current.

[0015] Secondly, this application also provides a current control device for a battery pack, comprising: a data acquisition module for acquiring target state data of each cell in the battery pack during the charging and discharging process of the battery pack, the target state data including at least one of voltage and temperature values; a reference current determination module for determining a target reference current of the battery pack based on a preset current control curve and the target state data, the current control curve including a mapping relationship between the cell state data and the reference current; and a current control module for reducing the target current value of the battery pack according to preset current control conditions and the target reference current, the target current value including the input current value and / or output current value of the battery pack, the current control conditions being related to the target reference current and the target current value.

[0016] Thirdly, this application also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method described in the first aspect.

[0017] Fourthly, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in the first aspect.

[0018] Fifthly, this application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the method described in the first aspect.

[0019] The aforementioned battery pack current control method acquires at least one of the voltage and temperature values ​​of each cell in the battery pack during the charging and discharging process. Based on a preset current control curve and the voltage and / or temperature values ​​of each cell, a target reference current for the battery pack is determined. The current control curve includes a mapping relationship between the cell state data and the reference current. The target current value of the battery pack is reduced according to preset current control conditions and the target reference current. The target current value includes the output current value and / or input current value of the battery pack. The current control conditions are related to the target reference current and the target current value of the battery pack. This method achieves real-time current control of the battery pack, avoids the impact of current overload on the battery pack's lifespan, and improves the timeliness of current control of the battery pack. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is an application environment diagram of the current control method for a battery pack in one embodiment;

[0022] Figure 2 This is a flowchart illustrating a current control method for a battery pack in one embodiment;

[0023] Figure 3 This is a schematic diagram of the first current control curve in one embodiment;

[0024] Figure 4 This is a schematic diagram of the second current control curve in one embodiment;

[0025] Figure 5 This is a schematic diagram of the third current control curve in one embodiment;

[0026] Figure 6 This is a schematic diagram of the fourth current control curve in one embodiment;

[0027] Figure 7 This is a flowchart illustrating step 203 in one embodiment;

[0028] Figure 8 This is a flowchart illustrating the steps for reducing the target current value in one embodiment;

[0029] Figure 9 This is a flowchart illustrating the step of reducing the target current value in another embodiment;

[0030] Figure 10 This is a flowchart illustrating step 202 in one embodiment;

[0031] Figure 11 This is a flowchart illustrating the steps for determining the first target reference current in one embodiment;

[0032] Figure 12 This is a flowchart illustrating the steps for determining the first target reference current in another embodiment;

[0033] Figure 13 This is a flowchart illustrating the steps for determining the second target reference current in one embodiment;

[0034] Figure 14 This is a flowchart illustrating step 203 in another embodiment;

[0035] Figure 15 This is a flowchart illustrating the current control method for a battery pack in another embodiment;

[0036] Figure 16 This is a structural block diagram of the current control device for a battery pack in one embodiment;

[0037] Figure 17 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0039] It should be noted that the terms "first," "second," etc., used in this application can be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from the second element. The terms "comprising" and "having," and any variations thereof, used in this application, are intended to cover non-exclusive inclusion. The term "multiple" used in this application refers to two or more. The term "and / or" used in this application refers to one of the embodiments, or any combination of multiple embodiments.

[0040] The battery pack current control method provided in this application embodiment can be applied to, for example... Figure 1 The application environment shown includes at least a battery pack 101, multiple battery cells 101-1, and a battery control device 102.

[0041] The battery pack 101 includes multiple battery cells 101-1. The battery pack 101 is used for charging and discharging according to the instructions of the battery management system and / or battery control device 102. The battery management system (BMS) can collect the status data of each battery cell 101-1 and send the status data to the battery control device 102.

[0042] The battery control device 102 is used to acquire target state data of each cell 101-1 in the battery pack 101, determine the target reference current of the battery pack based on a preset current control curve and the target state data, and reduce the target current value of the battery pack 101 according to the current control conditions and the target reference current. The battery control device 102 can be a control unit of the battery management system, or the battery management system can be a subsystem of the battery control device 102. Alternatively, the battery control device can be an independent device separate from the battery management system. The battery control device 102 can be a microserver deployed inside the battery pack 101; alternatively, it can be an external device that communicates with the battery management system via a network. This external device can be an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing cloud computing services.

[0043] In one exemplary embodiment, such as Figure 2 As shown, a current control method for a battery pack is provided, which is applied to... Figure 1 The following steps are used as an example of the battery control device in the process of illustration, including steps 201 to 203.

[0044] Step 201: During the charging and discharging process of the battery pack, acquire the target state data of each cell in the battery pack.

[0045] In this application, target state data refers to the state data of each cell in the battery pack. The state data of a cell can be the voltage value and / or temperature value of the cell. Target state data includes at least one of voltage value and temperature value. The voltage value can be the charging voltage value or the discharging voltage value, and the temperature value can be the charging temperature value or the discharging temperature value.

[0046] During implementation, as the battery pack is charging and discharging, the battery control device acquires the target state data of each cell in the battery pack. During execution, the battery control device can receive the target state data transmitted by the battery management system, which may include the battery control device. In this case, the battery management system may be an offline system.

[0047] In addition, the battery control device can also acquire target status data sent by the battery management system via the network. In this case, the battery control device and the battery management system can be online systems.

[0048] Step 202: Determine the target reference current of the battery pack based on the preset current control curve and the target state data.

[0049] In this application, the current control curve can be a pre-determined curve stored in the battery control device. The current control curve includes the mapping relationship between the cell's state data and the reference current; for example, the current control curve may include the mapping relationship between the cell's reference current and voltage value. Specifically, when the battery management system and battery control device are offline, the current control curve can be stored in the battery management system and / or battery control device; when the battery management system and battery control device are online, the current control curve can be stored in the battery control device.

[0050] Furthermore, when the battery control device is online, it can simultaneously control multiple battery modules of different models, and the current control curve for each model of battery module can be different; in this regard, the target state data can also include the battery model.

[0051] In one optional embodiment provided in this application, the current control curve includes: a first current control curve characterizing the mapping relationship between the current value and the voltage value in each cell, and a second current control curve characterizing the mapping relationship between the current value and the temperature value in each cell.

[0052] The first current control curve includes: a third current control curve representing the mapping relationship between the current value and the maximum voltage value in each cell during the charging state; and a fourth current control curve representing the mapping relationship between the current value and the minimum voltage value in each cell during the discharging state.

[0053] Regarding the third current control curve, during the charging process, the battery cell will experience a gradual increase in voltage. During this period, the charging current remains constant. After the voltage rises from the first voltage threshold to the second voltage threshold, that is, when the cell is almost fully charged, the charging current will gradually decrease linearly with the first slope k1 until the third voltage threshold is reached, that is, until the cell is fully charged.

[0054] For example, such as Figure 3 As shown, during the charging process, the maximum cell voltage gradually increases from 2.8V to 3.4V. During this period, the charging current is limited to 0.5C. When the maximum cell voltage charges from 3.4V to 3.6V, the charging current limit linearly decreases from 0.5C to 0.04C with a first slope k1 of -2.3. That is, the charging current limit at this time = (8.32 - 2.3 * maximum cell voltage)C. The maximum cell voltage in the formula refers to the maximum cell voltage in units of V, without the voltage unit V. For example, when the maximum cell voltage is 3.6V, the corresponding charging current limit = (8.32 - 2.3 * 3.6)C = 0.04C. Subsequent formulas are similar and will not be repeated here. When the maximum cell voltage exceeds 3.6V, the charging current limit is 0. This is understandable. Figures 3-4 For example, the normal operating voltage range of this product is between 2.8V and 3.6V. If it exceeds this range, it will be treated as a fault. For example, when the voltage is below 2.8V, the charging current can be limited to 0 or a very small charging current (e.g., 0.1C). No restrictions are imposed here.

[0055] In this application, the unit "C" (also known as C-rate) is a standardized unit of current relative to the rated capacity of the battery, used to express the charge and discharge rate. 1C current means: the amount of current required to discharge the battery from full charge (or charge it from empty to full charge) in 1 hour, and the specific value is determined by the rated capacity of the battery.

[0056] Regarding the fourth current control curve, the battery pack will experience a gradual decrease in voltage during the discharge process. During this period, the discharge current remains constant. After decreasing from the fourth voltage threshold to the fifth voltage threshold, that is, after the battery is almost depleted, the discharge current will gradually decrease linearly with the second slope k2 until it reaches the sixth voltage threshold, that is, until the battery cell is depleted.

[0057] For example, such as Figure 4 As shown, during the discharge process, the minimum cell voltage gradually decreases from 3.6V to 3.0V. During this period, the charging current is limited to 0.5C. While the minimum cell voltage discharges from 3.0V to 2.8V, the charging current limit decreases linearly from 0.5C to 0C with a second slope k2 of -1.5. That is, the charging current limit at this time is (5 - 1.5 * minimum cell voltage value)C. When the minimum cell voltage is less than 2.8V, the charging current limit is 0.

[0058] The second current control curve includes: a fifth current control curve representing the mapping relationship between the current value and the maximum temperature value in each cell during the charging state; and a sixth current control curve representing the mapping relationship between the current value and the maximum temperature value in each cell during the discharging state.

[0059] Regarding the fifth current control curve, during charging, the maximum cell temperature continuously increases with the increase of charging current. Then, the charging current reaches a stable period, during which the maximum cell temperature continues to increase. Towards full charge, the charging current decreases, but the maximum cell temperature continues to rise until the cell is fully charged and the maximum cell temperature stabilizes. During the current increase, it first rises linearly with a third slope (k3) to reach the first temperature, then with a fourth slope (k4) to reach the second temperature, then with a fifth slope (k5) to reach the third temperature, then maintains a slope of 0 to reach the fourth temperature, then linearly decreases with a sixth slope (k6) to reach the fifth temperature, then maintains a slope of 0 to reach the sixth temperature, and finally linearly decreases with a seventh slope (k7) to reach the seventh temperature. This is understandable. Figures 5-6 For example, the normal operating temperature range of this product is between -20℃ and 60℃. If it exceeds this range, it will be treated as a fault. For example, when the temperature is below -20℃, the charging current can be limited to 0 or a very small charging current (e.g., 0.1C). No restrictions are imposed here.

[0060] For example, such as Figure 5As shown, when the charging current is 0.04C, the maximum cell temperature is between -10℃ and 2℃. After charging begins, the charging current increases from 0.04C to 0.1C with a third slope k3 of 0.02, and the maximum cell temperature rises to 5℃. At this point, the charging current limit is (0.02 * maximum cell temperature)C. The maximum cell voltage value in the formula refers to the maximum cell temperature value in ℃, without temperature units in Celsius. For example, when the maximum cell temperature is 5℃, the corresponding charging current limit is (0.02 * 5)C = 0.1C. Subsequent formulas are similar and will not be repeated here. Subsequently, when the charging current increases from 0.1C to 0.35C with a fourth slope k4 of 0.05, the maximum cell temperature rises to 10℃. At this point, the charging current limit is (-0.15 + 0.05 * maximum cell temperature)C. Then, the charging current decreases from 0.35C to 0.04C with a third slope k3 of 0.02. When the fifth slope k5 of the 03 charge current climbs to 0.5C, the charging current limit at this point is (0.05 + 0.05 * maximum cell temperature)C, and the maximum cell temperature rises to 15℃. Afterward, the charging current stabilizes at 0.5C, and the maximum cell temperature climbs to 45℃ with a slope of 0. Subsequently, the charging current begins to decrease. When the charging current decreases from 0.05C to 0.27C with a sixth slope k6 of -0.046, the charging current limit at this point is (2.57 - 0.046 * maximum cell temperature)C, and the maximum cell temperature climbs to 50℃. The charging current will remain at 0.27C for a period of time, at which point the slope of the charging current is 0. Subsequently, the charging current decreases to 0.04C with a seventh slope k7 of -0.054, and the charging current limit at this point is (3.24 - 0.054 * maximum cell temperature)C, thus controlling the maximum cell temperature within 60℃.

[0061] Regarding the sixth current control curve, during the discharge process, the maximum temperature of the cell will continuously rise with the discharge action. Generally speaking, the discharge current will first rise linearly to a stable value with the eighth slope k8, and then decrease linearly with the ninth slope k9 when the charge is almost depleted. During this period, the maximum temperature of the cell will continue to increase.

[0062] For example, such as Figure 6 As shown, the discharge current of the battery cell increases from 0C with an eighth slope k8 of 0.05 to a stable value of 0.5C, and the maximum temperature of the battery cell increases from -20℃ to -10℃. At this time, the charging current limit is (0.1 + 0.05 * maximum temperature of the battery cell)C. Then, the discharge current is maintained at 0.5C with a slope of 0, and the maximum temperature of the battery cell will climb from -10℃ to 55℃. Subsequently, the discharge current of the battery cell decreases from the stable value of 0.5C to 0C with a ninth slope k9 of -0.25 due to the depletion of the battery. At this time, the charging current limit is (14.25 - 0.25 * maximum temperature of the battery cell)C, and the maximum temperature of the battery cell increases from 55℃ to 57℃.

[0063] The current control curve is calculated by obtaining the maximum target state value, which ensures that the calculated reference current value is most suitable for the battery pack, thus improving the reliability and accuracy of the target reference current.

[0064] During implementation, the battery control device iterates through the current control curve based on the target state data to obtain the target reference current corresponding to the target state data.

[0065] During execution, in order to improve the life of the battery pack, the current control curve can be traversed based on the voltage value to obtain the current corresponding to the voltage value, and the current control curve can be traversed based on the temperature value to obtain the current corresponding to the temperature value. The minimum current between the two can be selected as the target reference current.

[0066] Step 203: Reduce the target current value of the battery pack according to the preset current control conditions and target reference current.

[0067] During execution, the battery control device detects whether the target current value of the battery pack meets the preset current control conditions. If it does, it indicates that the target current value of the battery pack is too high, and the current value of the battery pack is reduced. If it does not meet the conditions, it indicates that the target current value of the battery pack is normal, and no action is taken. Furthermore, the battery control device can reduce the current value of the battery pack to the target reference current value, or it can directly stop the charging and discharging operation of the battery pack. The target current value includes the input current value and / or output current value of the battery pack; the current control conditions are related to the target reference current and the target current value of the battery pack.

[0068] During execution, the battery control device acquires the target current value of the battery pack, detects whether the target current value is greater than the target reference current value, and whether the duration for which the current value is greater than the target reference current value is greater than a time threshold. If yes, it indicates that the current value of the cell exceeds the current limit and current control is required; if no, it indicates that the current value of the cell does not exceed the current limit and current control is not required.

[0069] In this application, the current control condition is a judgment condition used to determine whether the battery cell needs current control; the current control condition is related to the target reference current. In one optional embodiment provided by this application, the current control condition includes: the target current value is greater than the target reference current, and the duration of the target current value is greater than a time threshold, and / or, the target current value is greater than a lower current limit threshold.

[0070] For example, current control conditions may include: the target current value exceeds the target reference current value for a period of 15 seconds. Alternatively, current control conditions may be set as: the target current value is greater than a preset multiple of the target reference current, and the duration of the target current value exceeds a time threshold; for example: the current value exceeds 150% of the target reference current value for a period of 15 seconds.

[0071] Furthermore, current control can also be performed when the target current value is greater than the lower current threshold. This is because the battery still has a current ramp-up phase, during which the current value is generally small, which may lead to misjudgment. Therefore, the current control conditions may include: the target current value is greater than the target reference current, the duration of the target current value is greater than the time threshold, and the target current value is greater than the lower current threshold. Optionally, the lower current threshold is 6A-8A.

[0072] It should be noted that the battery control device in this application can be a battery control device for a multi-battery pack system. The battery control device can calculate the target reference current for each battery pack and detect whether the current value of each battery pack meets the current control conditions. If multiple battery packs meet the current control conditions, current control is performed on multiple battery packs simultaneously, that is, the current value of multiple battery packs is reduced simultaneously. Furthermore, the battery control device can also obtain the current control results of each battery pack and perform current control on multiple battery packs based on the current control results.

[0073] In the aforementioned current control method for the battery pack, during the charging and discharging process of the battery pack, at least one of the voltage and temperature values ​​of each cell in the battery pack is acquired. Based on a preset current control curve and the voltage and / or temperature values ​​of each cell, a target reference current for the battery pack is determined. The current control curve includes the mapping relationship between the cell state data and the reference current. The target current value of the battery pack is reduced according to preset current control conditions and the target reference current. The target current value includes the output current value and / or input current value of the battery pack. The current control conditions are related to the target reference current and the target current value of the battery pack, thereby achieving real-time current control of the battery pack, avoiding the impact of current overload on the battery pack's lifespan, and improving the timeliness of current control of the battery pack.

[0074] Based on the above exemplary embodiment, the following provides a current control method for a battery pack in one or more exemplary embodiments, which is applied to... Figure 1 The following explanation will be based on the battery control device in the example.

[0075] During the current control process of the battery control device, it can detect whether the target current value of the battery pack meets the current control adjustment, and adjust the target current value if the current control adjustment is met; in one optional embodiment provided by this application, such as Figure 7 As shown, step 203 includes steps 701 to 702:

[0076] Step 701: Detect whether the target current value meets the current control conditions.

[0077] During implementation, the battery control equipment acquires the target current value of the battery pack in real time and checks whether the target current value meets the current control conditions. If the target current value meets the current control conditions, it indicates that the battery pack needs to be current controlled.

[0078] Step 702: If the target current value meets the current control conditions, reduce the target current value to the target reference current.

[0079] During implementation, if the target current value meets the current control conditions, it indicates that current control of the battery pack is required, and the battery control device will reduce the target current value to the target reference current.

[0080] During execution, the battery control device can work with the inverter of the electrical equipment to reduce the target current value to the target reference current.

[0081] One optional implementation provided in this application controls the current by setting current control conditions, thereby improving the reliability and accuracy of current control and ensuring its stability.

[0082] During the adjustment of the current value, the battery pack may be equipped with an inverter for precise current control, or it may be unequipped for coarse control. In one optional embodiment provided in this application, when the battery pack is equipped with an inverter, such as... Figure 8 As shown, reducing the target current value to the target reference current includes step 801:

[0083] Step 801: Generate a current control command based on the target reference current and send the current control command to the inverter corresponding to the battery pack.

[0084] Among them, the current control command is used to instruct the inverter to adjust the current value of the target cell to the target reference current.

[0085] During implementation, the battery control device generates a current control command based on the target reference current and sends the current control command to the inverter corresponding to the battery pack. After receiving the current control command, the inverter reduces the target current value of the battery pack to the current value corresponding to the target reference current.

[0086] One optional implementation provided in this application uses the inverter of the battery pack to control the current of the battery pack, which effectively utilizes the original components of the battery pack and improves the availability and utilization rate of the original components of the battery pack.

[0087] Furthermore, there are cases where the inverter fails to control the current value of the battery pack. In such cases, the charging and discharging of the battery cells can be directly controlled to stop. One optional implementation provided in this application is as follows: Figure 9 As shown, the method further includes step 901:

[0088] Step 901: Obtain the current value of the battery pack. If the current value of the battery pack is greater than the target reference current, control the battery pack to stop charging and discharging.

[0089] During implementation, the battery control device controls the current value of the battery pack through the inverter and then obtains the current value of the battery pack a second time. If the current value of the battery pack is greater than the target reference current, it indicates that the inverter has not controlled the current value of the battery pack and controls the battery pack to stop charging and discharging. If the current value of the battery pack is less than or equal to the target reference current, it indicates that the inverter has successfully controlled the current value of the battery pack.

[0090] One optional implementation provided in this application continuously monitors the current value of the battery pack to avoid overcurrent caused by the inverter, thereby further improving the effectiveness and timeliness of the battery pack current control.

[0091] In addition, there are cases where the battery pack does not include an inverter, in which case the battery pack can be directly controlled to stop charging and discharging; in one optional embodiment provided in this application, adjusting the current value of the battery pack includes: controlling the battery pack to stop charging and discharging.

[0092] During implementation, the battery control equipment controls the battery pack to stop charging and discharging.

[0093] One optional implementation provided in this application directly controls the battery pack to stop charging and discharging when the current value exceeds the target reference current value, thereby protecting the battery cells and extending their lifespan. At the same time, timely current processing improves the timeliness of current control.

[0094] In determining the target reference current, a current control curve corresponding to the battery pack's usage state can be determined based on the current control curve and target state data. In one optional implementation provided in this application, such as... Figure 10 As shown, step 202 includes steps 1001 to 1003:

[0095] Step 1001: Based on the usage status of the battery pack, determine the first current control curve corresponding to the voltage and the second current control curve corresponding to the temperature from multiple current control curves.

[0096] In this application, the usage state refers to the charging and discharging state of the battery pack, which includes the charging state and the discharging state.

[0097] During implementation, the battery control device can select a first current control curve corresponding to voltage and a second current control curve corresponding to temperature from multiple current control curves based on the charge / discharge state of the battery pack. The first current control curve may include a third current control curve corresponding to voltage during charging and a fourth current control curve corresponding to voltage during discharging. The second current control curve may include a fifth current control curve corresponding to temperature during charging and a sixth current control curve corresponding to temperature during discharging.

[0098] During execution, if the battery pack is in a charging state, the third current control curve corresponding to the voltage and the fifth current control curve corresponding to the temperature are selected from multiple current control curves. If the battery pack is in a discharging state, the fourth current control curve corresponding to the voltage and the sixth current control curve corresponding to the temperature are selected from multiple current control curves.

[0099] Step 1002: Determine the first target reference current based on the first current control curve and each voltage value, and determine the second target reference current based on the second current control curve and each temperature value.

[0100] During implementation, the battery control device can determine the first target reference current based on the first current control curve and each voltage value, and determine the second target reference current based on the second current control curve and each temperature value.

[0101] During execution, the battery control device can select the third or fourth current control curve and each voltage value to determine the first target reference current, and select the fifth or sixth current control curve and each temperature value to determine the second target reference current.

[0102] Step 1003: Determine the smaller value between the first target reference current and the second target reference current as the target reference current.

[0103] During implementation, the battery control device compares the values ​​of the first target reference current and the second target reference current, and selects the reference current with the smallest value between the first target reference current and the second target reference current as the target reference current.

[0104] One optional implementation provided in this application calculates the reference current corresponding to voltage and temperature and selects the minimum reference current as the target reference current, which ensures the rationality of the charging and discharging current of the battery pack. At the same time, by using a simple numerical comparison method, the computational power required is reduced, thereby ensuring the timeliness of the control response.

[0105] In practical scenarios, to ensure the reliability of the calculated target reference current, when the battery is in a charging state, the highest voltage value among the cells can be selected to calculate the first target reference current; one optional implementation method provided in this application is as follows: Figure 11 As shown, the process of determining the first target reference current includes steps 1101 to 1102:

[0106] Step 1101: Select the maximum voltage value from all voltage values.

[0107] During implementation, the battery control equipment selects the maximum voltage value from the voltage values ​​of each cell.

[0108] Step 1102: Traverse the first current control curve according to the maximum voltage value to obtain the first target reference current corresponding to the maximum voltage value.

[0109] During implementation, the battery control device iterates through the first current control curve based on the maximum voltage value to obtain the first target reference current corresponding to the maximum voltage value.

[0110] Furthermore, the battery control device can traverse the third current control curve based on the maximum voltage value to obtain the first target reference current corresponding to the maximum voltage value.

[0111] In addition, when the battery is in a discharged state, the minimum voltage value among the cells can be selected to calculate the first target reference current; another optional embodiment provided in this application is as follows: Figure 12 As shown, the process of determining the first target reference current includes steps 1201 to 1202:

[0112] Step 1201: Select the minimum voltage value from all voltage values.

[0113] During implementation, the battery control equipment selects the minimum voltage value from the voltage values ​​of each cell.

[0114] Step 1202: Traverse the first current control curve according to the minimum voltage value to obtain the first target reference current corresponding to the minimum voltage value.

[0115] During implementation, the battery control device traverses the first current control curve based on the minimum voltage value to obtain the first target reference current corresponding to the minimum voltage value.

[0116] Furthermore, the battery control device can traverse the fourth current control curve based on the minimum voltage value to obtain the first target reference current corresponding to the minimum voltage value.

[0117] One optional implementation provided in this application calculates the target reference current based on the voltage value in the battery cell and the usage status of the battery pack, so that the calculated first target reference current is reliable and accurate, and is also compatible with the remaining battery cells in the battery pack.

[0118] In practical scenarios, to ensure the reliability of the calculated target reference current, the second target reference current can be calculated by selecting the highest temperature value among the various battery cells; one optional implementation method provided in this application is as follows: Figure 13 As shown, the process of determining the second target reference current includes steps 1301 to 1302:

[0119] Step 1301: Filter out the maximum temperature value from all temperature values.

[0120] During implementation, the battery control equipment selects the maximum temperature value with the highest value from the temperature values ​​of each cell.

[0121] Step 1302: Based on the maximum temperature value, traverse the second current control curve to obtain the second target reference current corresponding to the maximum temperature value.

[0122] During implementation, the battery control device iterates through the second current control curve based on the maximum temperature value to obtain the second target reference current corresponding to the maximum voltage value. During execution, in the charging state, the battery control device can iterate through the fifth current control curve based on the maximum temperature value to obtain the second target reference current corresponding to the maximum temperature value; in the discharging state, the battery control device can iterate through the sixth current control curve based on the maximum temperature value to obtain the second target reference current corresponding to the maximum temperature value.

[0123] One optional implementation provided in this application calculates the target reference current based on the maximum temperature value in the battery cell, making the calculated second target reference current reliable and accurate, while also being compatible with the remaining battery cells in the battery pack.

[0124] In real-world scenarios, there are also multi-battery pack systems with multiple battery packs connected in parallel. The current value of this system is the sum of the currents of each battery pack. In such systems, the current values ​​of each battery pack may differ, and consequently, the target reference currents for each battery pack may also differ. To address this, current control can be performed based on the minimum target reference current among the overcurrent battery packs to improve battery pack safety. One optional implementation provided in this application is as follows: Figure 14 As shown, step 203 includes steps 1401 to 1403:

[0125] Step 1401: Obtain the first target reference current of the first battery pack connected in parallel with the battery pack.

[0126] During implementation, the battery control device first identifies multiple overcurrent battery packs in the multi-battery pack system. Specifically, it identifies the battery pack and the first battery pack in the multi-battery pack system. There can be multiple first battery packs. After identifying the battery pack and the first battery pack, it obtains the first target reference current of the first battery pack. The battery pack and the first battery pack can be connected in parallel, and the current value of the first battery pack meets the current control conditions.

[0127] During execution, the battery control device can calculate the first target reference current of the first battery pack on its own; in addition, the battery control device can also obtain the first target reference current of the first battery pack calculated by the first battery control device and sent to the first battery control device.

[0128] Step 1402: Select the minimum target reference current from the first target reference current and the target reference current.

[0129] During implementation, the battery control device selects the minimum target reference current with the smallest value from among multiple first target reference currents and target reference currents.

[0130] Step 1403: Reduce the target current value and the first current value of the first battery pack to the minimum target reference current.

[0131] During implementation, the battery control device reduces the target current value of the battery pack and the first current value of the first battery pack to the minimum target reference current. During execution, the battery control device can communicate with the inverter corresponding to the multi-battery pack system to perform current control.

[0132] One optional implementation provided in this application is to perform current control based on the minimum target reference current in a multi-battery pack system with multiple battery packs connected in parallel. This ensures the current consistency of the multiple battery packs and improves the current control efficiency, thereby ensuring the lifespan of the battery packs and the timeliness of the current control.

[0133] In one embodiment, see Figure 15 The document illustrates a flowchart of a current control method for a battery pack according to an embodiment of this application. This current control method for a battery pack can be applied to... Figure 1 In the battery control device shown. For example... Figure 15 As shown, the current control method for this battery pack may include the following steps:

[0134] Step 1501: During the charging and discharging process of the battery pack, acquire the target state data of each cell in the battery pack.

[0135] Step 1502: Based on the usage status of the battery pack, determine the first current control curve corresponding to the voltage and the second current control curve corresponding to the temperature from multiple current control curves.

[0136] Step 1503: Select the voltage value corresponding to the operating state from the various voltage values, and traverse the first current control curve according to the voltage value to obtain the first target reference current corresponding to the voltage value.

[0137] Step 1504: Select the maximum temperature value from all temperature values, and traverse the second current control curve according to the maximum temperature value to obtain the second target reference current corresponding to the maximum temperature value.

[0138] Step 1505: Determine the smaller value between the first target reference current and the second target reference current as the target reference current.

[0139] Step 1506: Obtain the target current value of the battery pack, and detect whether the target current value is greater than the target reference current and whether the duration of the target current value is greater than the time threshold.

[0140] Step 1507: If the target current value is greater than the target reference current and the duration of the target current value is greater than the time threshold, the battery pack is controlled to stop charging and discharging by the inverter of the battery pack.

[0141] It should be noted that any one or more of steps 1501 to 1507 can be combined to form a new implementation method according to the needs of implementation and deployment. Furthermore, any one or more technical features in the technical solution composed of steps 1501 to 1507 can also be combined to form a new implementation method according to the actual deployment needs, or technical features in one or more optional implementation methods provided by one or more of the above embodiments can be combined to form a new implementation method. These will not be elaborated on here.

[0142] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages in other steps. It is understood that the steps in different embodiments can be freely combined as needed, and all non-contradictory solutions formed by such combinations are within the scope of protection of this application.

[0143] Based on the same inventive concept, this application also provides a current control device for a battery pack to implement the current control method for the battery pack described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations of the one or more embodiments of the current control device for the battery pack provided below can be found in the limitations of the current control method for the battery pack described above, and will not be repeated here.

[0144] In one exemplary embodiment, such as Figure 16 As shown, a current control device for a battery pack is provided, including: a data acquisition module 1601, a reference current determination module 1602, and a current control module 1603. The data acquisition module 1601 is used to acquire target state data of each cell in the battery pack during the charging and discharging process. The target state data includes at least one of voltage and temperature values. The reference current determination module 1602 is used to determine a target reference current for the battery pack based on a preset current control curve and the target state data. The current control curve includes a mapping relationship between the cell state data and the reference current. The current control module 1603 is used to reduce the target current value of the battery pack according to preset current control conditions and the target reference current. The target current value includes the input current value and / or output current value of the battery pack. The current control conditions are related to the target reference current and the target current value.

[0145] In one embodiment, the current control module 1603 includes a detection unit and a current adjustment unit, wherein: the detection unit is used to detect whether the target current value meets the current control conditions; and the current adjustment unit is used to reduce the target current value to the target reference current if the target current value meets the current control conditions.

[0146] In one embodiment, the current adjustment unit includes an inverter control unit, which is configured to: generate a current control command based on a target reference current, and send the current control command to the inverter corresponding to the battery pack, wherein the current control command is configured to instruct the inverter to reduce the current value of the battery pack to the target reference current.

[0147] In one embodiment, the device further includes a first current control module, which is used to acquire the current value of the battery pack. If the current value of the battery pack is greater than the target reference current, the module controls the battery pack to stop charging and discharging.

[0148] In one embodiment, the reference current determination module 1602 includes a curve determination unit, a first determination unit, and a second determination unit, wherein: the curve determination unit is used to determine a first current control curve corresponding to voltage and a second current control curve corresponding to temperature from multiple current control curves according to the usage state of the battery pack, the usage state including charging state and discharging state; the first determination unit is used to determine a first target reference current according to the first current control curve and each voltage value, and to determine a second target reference current according to the second current control curve and each temperature value; the second determination unit is used to determine the minimum value between the first target reference current and the second target reference current as the target reference current.

[0149] In one embodiment, the first determining unit includes a first filtering unit and a first traversal unit, wherein: the first filtering unit is used to filter out the maximum voltage value among the voltage values; the first traversal unit is used to traverse the first current control curve according to the maximum voltage value to obtain the first target reference current corresponding to the maximum voltage value.

[0150] In one embodiment, the second determining unit includes a charging determining unit and / or a discharging determining unit, wherein: the charging determining unit is configured to, when the usage state is charging state, select the maximum voltage value from each voltage value, and traverse the first current control curve according to the maximum voltage value to obtain the first target reference current corresponding to the maximum voltage value; the discharging determining unit is configured to, when the usage state is discharging state, select the minimum voltage value from each voltage value, and traverse the first current control curve according to the minimum voltage value to obtain the first target reference current corresponding to the minimum voltage value.

[0151] In one embodiment, the device further includes a first target reference current acquisition module, a filtering module, and a current reduction module, wherein: the first target reference current acquisition module is used to acquire a first target reference current of a first battery pack connected in parallel with the battery pack, and the current value of the first battery pack satisfies the current control condition; the filtering module is used to filter out the minimum target reference current from the first target reference current and the target reference current; and the current reduction module is used to reduce the target current value and the first current value of the first battery pack to the minimum target reference current.

[0152] The modules in the current control device of the aforementioned battery pack can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the operations corresponding to each module.

[0153] In one exemplary embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 17 As shown, this computer device includes a processor, memory, input / output interfaces (I / O), and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operating system and computer programs stored in the non-volatile storage media. The database stores current control data for the battery pack. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communicating with external terminals via a network connection. When the computer program is executed by the processor, it implements a current control method for the battery pack.

[0154] Those skilled in the art will understand that Figure 17 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0155] In one exemplary embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to perform the following steps: during the charging and discharging process of a battery pack, acquiring target state data of each cell in the battery pack, the target state data including at least one of voltage and temperature values; determining a target reference current for the battery pack based on a preset current control curve and the target state data, the current control curve including a mapping relationship between the cell state data and the reference current; reducing the target current value of the battery pack according to preset current control conditions and the target reference current, the target current value including the input current value and / or output current value of the battery pack, the current control conditions being related to the target reference current and the target current value.

[0156] In one embodiment, when the processor executes the computer program, it further performs the following steps: detecting whether the target current value meets the current control conditions; if the target current value meets the current control conditions, reducing the target current value to the target reference current.

[0157] In one embodiment, when the processor executes the computer program, it further performs the following steps: generating a current control instruction based on the target reference current and sending the current control instruction to the inverter corresponding to the battery pack. The current control instruction is used to instruct the inverter to reduce the current value of the battery pack to the target reference current.

[0158] In one embodiment, when the processor executes the computer program, it also performs the following steps: obtaining the current value of the battery pack, and if the current value of the battery pack is greater than the target reference current, controlling the battery pack to stop charging and discharging.

[0159] In one embodiment, when the processor executes the computer program, it further performs the following steps: determining a first current control curve corresponding to voltage and a second current control curve corresponding to temperature from multiple current control curves according to the usage state of the battery pack, wherein the usage state includes charging state and discharging state; determining a first target reference current according to the first current control curve and each voltage value, and determining a second target reference current according to the second current control curve and each temperature value; and determining the minimum value between the first target reference current and the second target reference current as the target reference current.

[0160] In one embodiment, when the processor executes the computer program, it further performs the following steps: when the usage state is charging state, selecting the maximum voltage value from each voltage value, traversing the first current control curve according to the maximum voltage value, and obtaining the first target reference current corresponding to the maximum voltage value; and / or, when the usage state is discharging state, selecting the minimum voltage value from each voltage value, traversing the first current control curve according to the minimum voltage value, and obtaining the first target reference current corresponding to the minimum voltage value.

[0161] In one embodiment, when the processor executes the computer program, it further performs the following steps: filtering out the maximum temperature value from the various temperature values; and traversing the second current control curve according to the maximum temperature value to obtain the second target reference current corresponding to the maximum temperature value.

[0162] In one embodiment, when the processor executes the computer program, it further performs the following steps: obtaining a first target reference current of a first battery pack connected in parallel with the battery pack, wherein the current value of the first battery pack satisfies the current control condition; selecting the minimum target reference current from the first target reference current and the target reference current; and reducing the target current value and the first current value of the first battery pack to the minimum target reference current.

[0163] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0164] During the charging and discharging process of the battery pack, target state data of each cell in the battery pack is acquired. The target state data includes at least one of voltage and temperature values. Based on the preset current control curve and the target state data, the target reference current of the battery pack is determined. The current control curve includes the mapping relationship between the cell state data and the reference current. The target current value of the battery pack is reduced according to the preset current control conditions and the target reference current. The target current value includes the input current value and / or output current value of the battery pack. The current control conditions are related to the target reference current and the target current value.

[0165] In one embodiment, when the processor executes the computer program, it further performs the following steps: detecting whether the target current value meets the current control conditions; if the target current value meets the current control conditions, reducing the target current value to the target reference current.

[0166] In one embodiment, when the processor executes the computer program, it further performs the following steps: generating a current control instruction based on the target reference current and sending the current control instruction to the inverter corresponding to the battery pack. The current control instruction is used to instruct the inverter to reduce the current value of the battery pack to the target reference current.

[0167] In one embodiment, when the processor executes the computer program, it also performs the following steps: obtaining the current value of the battery pack, and if the current value of the battery pack is greater than the target reference current, controlling the battery pack to stop charging and discharging.

[0168] In one embodiment, when the processor executes the computer program, it further performs the following steps: determining a first current control curve corresponding to voltage and a second current control curve corresponding to temperature from multiple current control curves according to the usage state of the battery pack, wherein the usage state includes charging state and discharging state; determining a first target reference current according to the first current control curve and each voltage value, and determining a second target reference current according to the second current control curve and each temperature value; and determining the minimum value between the first target reference current and the second target reference current as the target reference current.

[0169] In one embodiment, when the processor executes the computer program, it further performs the following steps: when the usage state is charging state, selecting the maximum voltage value from each voltage value, traversing the first current control curve according to the maximum voltage value, and obtaining the first target reference current corresponding to the maximum voltage value; and / or, when the usage state is discharging state, selecting the minimum voltage value from each voltage value, traversing the first current control curve according to the minimum voltage value, and obtaining the first target reference current corresponding to the minimum voltage value.

[0170] In one embodiment, when the processor executes the computer program, it further performs the following steps: filtering out the maximum temperature value from the various temperature values; and traversing the second current control curve according to the maximum temperature value to obtain the second target reference current corresponding to the maximum temperature value.

[0171] In one embodiment, when the processor executes the computer program, it further performs the following steps: obtaining a first target reference current of a first battery pack connected in parallel with the battery pack, wherein the current value of the first battery pack satisfies the current control condition; selecting the minimum target reference current from the first target reference current and the target reference current; and reducing the target current value and the first current value of the first battery pack to the minimum target reference current.

[0172] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, performs the following steps:

[0173] During the charging and discharging process of the battery pack, target state data of each cell in the battery pack is acquired. The target state data includes at least one of voltage and temperature values. Based on the preset current control curve and the target state data, the target reference current of the battery pack is determined. The current control curve includes the mapping relationship between the cell state data and the reference current. The target current value of the battery pack is reduced according to the preset current control conditions and the target reference current. The target current value includes the input current value and / or output current value of the battery pack. The current control conditions are related to the target reference current and the target current value.

[0174] In one embodiment, when the processor executes the computer program, it further performs the following steps: detecting whether the target current value meets the current control conditions; if the target current value meets the current control conditions, reducing the target current value to the target reference current.

[0175] In one embodiment, when the processor executes the computer program, it further performs the following steps: generating a current control instruction based on the target reference current and sending the current control instruction to the inverter corresponding to the battery pack. The current control instruction is used to instruct the inverter to reduce the current value of the battery pack to the target reference current.

[0176] In one embodiment, when the processor executes the computer program, it also performs the following steps: obtaining the current value of the battery pack, and if the current value of the battery pack is greater than the target reference current, controlling the battery pack to stop charging and discharging.

[0177] In one embodiment, when the processor executes the computer program, it further performs the following steps: determining a first current control curve corresponding to voltage and a second current control curve corresponding to temperature from multiple current control curves according to the usage state of the battery pack, wherein the usage state includes charging state and discharging state; determining a first target reference current according to the first current control curve and each voltage value, and determining a second target reference current according to the second current control curve and each temperature value; and determining the minimum value between the first target reference current and the second target reference current as the target reference current.

[0178] In one embodiment, when the processor executes the computer program, it further performs the following steps: when the usage state is charging state, selecting the maximum voltage value from each voltage value, traversing the first current control curve according to the maximum voltage value, and obtaining the first target reference current corresponding to the maximum voltage value; and / or, when the usage state is discharging state, selecting the minimum voltage value from each voltage value, traversing the first current control curve according to the minimum voltage value, and obtaining the first target reference current corresponding to the minimum voltage value.

[0179] In one embodiment, when the processor executes the computer program, it further performs the following steps: filtering out the maximum temperature value from the various temperature values; and traversing the second current control curve according to the maximum temperature value to obtain the second target reference current corresponding to the maximum temperature value.

[0180] In one embodiment, when the processor executes the computer program, it further performs the following steps: obtaining a first target reference current of a first battery pack connected in parallel with the battery pack, wherein the current value of the first battery pack satisfies the current control condition; selecting the minimum target reference current from the first target reference current and the target reference current; and reducing the target current value and the first current value of the first battery pack to the minimum target reference current.

[0181] It should be noted that the data involved in this application (including but not limited to data used for analysis, data stored, data displayed, etc.) are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0182] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0183] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0184] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A current control method for a battery pack, characterized in that, The method includes: During the charging and discharging process of the battery pack, target state data of each cell in the battery pack is acquired, and the target state data includes at least one of voltage value and temperature value. Based on the preset current control curve and the target state data, the target reference current of the battery pack is determined. The current control curve includes the mapping relationship between the state data of the cells and the reference current. The target current value of the battery pack is reduced according to preset current control conditions and the target reference current. The target current value includes the input current value and / or output current value of the battery pack. The current control conditions are related to the target reference current and the target current value of the battery pack.

2. The method according to claim 1, characterized in that, The step of reducing the target current value of the battery pack according to the preset current control conditions and the target reference current includes: Detect whether the target current value meets the current control condition; If the target current value meets the current control condition, the target current value is reduced to the target reference current.

3. The method according to claim 2, characterized in that, The step of reducing the current value of the battery pack to the target reference current includes: A current control command is generated based on the target reference current and sent to the inverter corresponding to the battery pack. The current control command is used to instruct the inverter to reduce the current value of the battery pack to the target reference current.

4. The method according to claim 3, characterized in that, After sending the current control command to the inverter corresponding to the battery pack, the method further includes: The current value of the battery pack is obtained. If the current value of the battery pack is greater than the target reference current, the battery pack is controlled to stop charging and discharging.

5. The method according to claim 1, characterized in that, The current control conditions include: The target current value is greater than the target reference current, and the duration of the target current value is greater than a time threshold, and / or the target current value is greater than a lower current threshold.

6. The method according to any one of claims 1-5, characterized in that, Determining the target reference current of the battery pack based on the preset current control curve and each of the target state data includes: Based on the usage status of the battery pack, a first current control curve corresponding to voltage and a second current control curve corresponding to temperature are determined from multiple current control curves. The usage status includes charging status and discharging status. A first target reference current is determined based on the first current control curve and each of the voltage values, and a second target reference current is determined based on the second current control curve and each of the temperature values. The smaller value between the first target reference current and the second target reference current is determined as the target reference current.

7. The method according to claim 6, characterized in that, The step of determining the first target reference current based on the first current control curve and each of the voltage values ​​includes: When the usage state is charging state, the maximum voltage value is selected from the voltage values, and the first target reference current corresponding to the maximum voltage value is obtained by traversing the first current control curve according to the maximum voltage value. And / or, when the usage state is a discharge state, the minimum voltage value is selected from each of the voltage values, and the first target reference current corresponding to the minimum voltage value is obtained by traversing the first current control curve according to the minimum voltage value.

8. The method according to claim 6, characterized in that, The step of determining the second target reference current based on the second current control curve and each of the temperature values ​​includes: The maximum temperature value is selected from all the stated temperature values; The second target reference current is obtained by iterating through the second current control curve based on the maximum temperature value.

9. The method according to claim 1, characterized in that, The current control curve includes at least one of the following: A third current control curve representing the mapping relationship between the current value and the maximum voltage value in each of the cells during the charging state; A fourth current control curve characterizing the mapping relationship between the current value and the minimum voltage value in each of the cells under discharge conditions; The fifth current control curve, which characterizes the mapping relationship between the current value and the maximum temperature value in each of the cells during the charging state; The sixth current control curve, which characterizes the mapping relationship between the current value and the maximum temperature value in each of the cells under discharge conditions.

10. The method according to claim 1, characterized in that, The step of reducing the target current value of the battery pack according to the preset current control conditions and the target reference current includes: Obtain a first target reference current for the first battery pack connected in parallel with the battery pack, wherein the current value of the first battery pack satisfies the current control condition; Among the first target reference current and the target reference current, the minimum target reference current is selected; The target current value and the first current value of the first battery pack are reduced to the minimum target reference current.

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