WO2023028789A1 - 温度确定方法与电流阈值确定方法、电池管理系统 - Google Patents

温度确定方法与电流阈值确定方法、电池管理系统 Download PDF

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Publication number
WO2023028789A1
WO2023028789A1 PCT/CN2021/115473 CN2021115473W WO2023028789A1 WO 2023028789 A1 WO2023028789 A1 WO 2023028789A1 CN 2021115473 W CN2021115473 W CN 2021115473W WO 2023028789 A1 WO2023028789 A1 WO 2023028789A1
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Prior art keywords
temperature
battery pack
current
threshold
battery
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PCT/CN2021/115473
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English (en)
French (fr)
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陈敬轩
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宁德时代新能源科技股份有限公司
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Application filed by 宁德时代新能源科技股份有限公司 filed Critical 宁德时代新能源科技股份有限公司
Priority to PCT/CN2021/115473 priority Critical patent/WO2023028789A1/zh
Priority to CN202180082571.2A priority patent/CN116783757A/zh
Publication of WO2023028789A1 publication Critical patent/WO2023028789A1/zh

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/48—Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte

Definitions

  • the present application relates to the field of battery technology, in particular to a temperature determination method, a current threshold determination method, and a battery management system.
  • temperature is a more important parameter in its characteristics. Since the battery pack is provided with multiple cells, the temperature in the battery pack is usually unevenly distributed, that is, the temperature at different locations in the battery pack may be different. Then, how to choose a more suitable temperature as the current temperature of the battery pack is particularly important to accurately represent the actual situation of the battery pack.
  • the present application aims to provide a temperature determination method, a current threshold determination method, and a battery management system, which can improve the use efficiency of the battery pack and improve the safety of the battery pack during use.
  • the present application provides a method for determining temperature, which includes obtaining the highest temperature and the lowest temperature of the battery pack at the current moment. Obtain the over-temperature warning threshold and the under-temperature warning threshold. According to the maximum temperature, the minimum temperature, the over-temperature warning threshold and the under-temperature warning threshold, the battery pack temperature at the current moment is determined.
  • the obtained battery pack temperature can reflect the actual situation of the battery pack more accurately, which is conducive to making full use of the performance of the battery pack, namely The usage efficiency of the battery pack can be improved.
  • the over-temperature warning threshold and the under-temperature warning threshold it can also reduce false alarms, missed alarms, and possible safety risks, which is conducive to improving the safety of the battery pack during use.
  • At least two temperature sampling points are provided in the battery pack.
  • Obtaining the highest temperature and the lowest temperature of the battery pack at the current moment includes: obtaining sampling signals of each temperature sampling point, and obtaining the highest temperature and the lowest temperature of the battery pack at the current moment according to the sampling signals.
  • the temperature of multiple positions of the battery pack can be obtained, and then the obtained temperatures are compared.
  • the maximum value is the highest temperature of the battery pack, and the minimum value is the lowest temperature of the battery pack.
  • determining the temperature of the battery pack at the current moment according to the maximum temperature, the minimum temperature, the over-temperature warning threshold and the under-temperature warning threshold includes: if the maximum temperature is greater than the over-temperature warning threshold, or the maximum temperature If the difference with the lowest temperature is greater than the first difference, then the highest temperature is determined to be the battery pack temperature at the current moment.
  • some cells in the battery pack may be under high temperature conditions.
  • the temperature of the battery pack at the current moment is determined according to the highest temperature, the lowest temperature, the over-temperature warning threshold and the under-temperature warning threshold, including: if the highest temperature is less than or equal to the over-temperature warning threshold, and the highest temperature If the difference with the minimum temperature is less than or equal to the first difference, and the minimum temperature is less than the undertemperature warning threshold, then the minimum temperature is determined to be the battery pack temperature at the current moment.
  • some cells in the battery pack may be under the condition of too low temperature.
  • the battery pack is in a normal working condition, that is, the temperature of the battery pack is between the over-temperature warning threshold and the under-temperature warning threshold.
  • the temperature of the battery pack obtained by combining the maximum temperature, the minimum temperature, the over-temperature warning threshold and the under-temperature warning threshold can more accurately reflect the actual situation of the battery pack, which is conducive to improving the safety of the battery pack during use.
  • the performance of the battery pack can be more fully utilized, and the use efficiency of the battery pack is improved.
  • the present application also provides a method for determining a current threshold, including: obtaining the voltage or SOC value of each battery cell in the battery pack, wherein the battery pack includes at least one battery cell, and the SOC value is the difference between the remaining power of the battery cell and the SOC value of the battery cell. The ratio of the nominal capacity.
  • the current threshold for charging or discharging the battery pack at the current moment is determined.
  • the temperature of the battery pack at the current moment is determined by the highest temperature of the battery pack, the lowest temperature of the battery pack, the over-temperature warning threshold and the under-temperature warning threshold.
  • the temperature of the battery pack obtained by combining the maximum temperature, the minimum temperature, the over-temperature warning threshold and the under-temperature warning threshold can accurately reflect the actual situation of the battery pack, so as to improve the safety of the battery pack.
  • the current threshold determined by the temperature of the battery pack it is possible to increase the allowable charging or discharging current of the battery pack as much as possible on the premise of maintaining high safety of the battery pack, so as to improve the use efficiency of the battery pack .
  • the current threshold determined by this method is more in line with the real ability of charging or discharging the battery pack, which is conducive to reducing the heat generated by the cells in the battery pack due to excessive current that the cells cannot bear, and may ignite batteries, there is a risk of combustion and explosion.
  • the current threshold when the battery pack is charging or discharging at the current moment including: if the voltage of each cell is the same , the voltage of any cell is obtained as the first voltage, and the current threshold is determined according to the first voltage and the battery pack temperature at the current moment. Or, if the SOC values of all cells are the same, the SOC value of any cell is acquired as the first SOC value, and the current threshold is determined according to the first SOC value and the current battery pack temperature.
  • the current threshold can be determined according to the voltage or SOC value of any cell at the current moment and the temperature of the battery pack.
  • the current threshold when the battery pack is charging or discharging at the current moment including: if there is For at least two voltages with different magnitudes, the maximum voltage and the minimum voltage among the voltages of each battery cell are obtained. Determine the current threshold according to the maximum voltage, minimum voltage, and battery pack temperature at the current moment. Or, if there are at least two SOC values with different sizes among the SOC values of each battery core, then obtain the maximum SOC value and the minimum SOC value among the SOC values of each battery core. Determine the current threshold according to the maximum SOC value, the minimum SOC value and the current battery pack temperature.
  • the current threshold can be determined by combining the maximum voltage, minimum voltage and the current battery pack temperature. Therefore, the allowable charging or discharging current of the battery pack can be increased to a large extent, so as to improve the use efficiency of the battery pack.
  • the method of obtaining the current threshold through the SOC value is similar to that of the voltage.
  • the current threshold is determined according to the maximum voltage, the minimum voltage, and the temperature of the battery pack at the current moment, or, the current threshold is determined according to the maximum SOC value, the minimum SOC value, and the temperature of the battery pack at the current moment, including : Obtain the first current threshold according to the maximum voltage and the current battery pack temperature. According to the minimum voltage and the temperature of the battery pack at the current moment, the second current threshold is obtained. The minimum value of the first current threshold and the second current threshold is used as the current threshold. Or, acquire the third current threshold according to the maximum SOC value and the battery pack temperature at the current moment. A fourth current threshold is acquired according to the minimum SOC value and the battery pack temperature at the current moment. The minimum value of the third current threshold and the fourth current threshold is used as the current threshold.
  • the corresponding relationship between the voltage or SOC value, the temperature of the battery pack, and the current threshold can be obtained by looking up the table, that is, the first current threshold and the second current threshold, or the third current threshold and the fourth current threshold can be obtained.
  • the current threshold when the battery pack is being charged or discharged at the current moment can be determined.
  • the method for determining the current threshold further includes: sending the current threshold to the charging device or the electric device, so that the charging device controls its charging current to be less than the current threshold, or uses the electric device to control its power consumption current to be less than the current threshold. current threshold.
  • the battery pack is used for being charged by the charging device, and for supplying power to the electric device.
  • the present application further provides a temperature determination device, including: a temperature acquisition module, configured to acquire the highest temperature and the lowest temperature of the battery pack at the current moment.
  • the early warning threshold acquisition module is used to acquire the over temperature early warning threshold and the under temperature early warning threshold.
  • the temperature determining module is used to determine the temperature of the battery pack at the current moment according to the maximum temperature, the minimum temperature, the over-temperature warning threshold and the under-temperature warning threshold.
  • the present application also provides a device for determining a current threshold, including: a power state acquisition module, configured to acquire the voltage or SOC value of each battery cell in the battery pack, wherein the battery pack includes at least one battery cell, and the SOC value is The ratio of the remaining power of the battery to the nominal capacity of the battery.
  • the current threshold determination module is used to determine the current threshold when the battery pack is charging or discharging at the current moment according to the voltage or SOC value of each battery cell and the temperature of the battery pack at the current moment. Wherein, the temperature of the battery pack at the current moment is determined by the highest temperature of the battery pack, the lowest temperature of the battery pack, the over-temperature warning threshold and the under-temperature warning threshold.
  • the present application further provides a temperature determining device, including: a memory; and a processor coupled to the memory, the processor is configured to execute the method in the first aspect based on instructions stored in the memory.
  • the present application further provides a device for determining a current threshold, including: a memory; and a processor coupled to the memory, and the processor is configured to execute the method in the second aspect based on instructions stored in the memory.
  • the present application further provides a battery management system, including the temperature determining device as in the third aspect or the fifth aspect, and/or, the current threshold determining device as in the fourth aspect or the sixth aspect.
  • the present application further provides a battery pack, including a battery module and the above battery management system, the battery management system is electrically connected to the battery module, wherein the battery module includes at least one battery.
  • the present application further provides an electric device, including a load and a battery pack as in the eighth aspect, where the battery pack is used to supply power to the load.
  • the present application further provides a computer-readable storage medium, including: computer-executable instructions are stored, and the computer-executable instructions are configured as the method flow in the first aspect and the second aspect.
  • the temperature determination method provided by the present application includes obtaining the highest temperature and the lowest temperature of the battery pack at the current moment, and obtaining the over-temperature warning threshold and the under-temperature warning threshold, and according to the maximum temperature, the minimum temperature , over-temperature warning threshold and under-temperature warning threshold to determine the battery pack temperature at the current moment.
  • the temperature of the battery pack obtained in this application can reflect the actual situation of the battery pack more accurately, which is conducive to making full use of the performance of the battery pack , thus, the usage efficiency of the battery pack can be improved.
  • due to the combination of the over-temperature warning threshold and the under-temperature warning threshold it can also reduce false alarms, missed alarms and possible safety risks, thereby improving the safety of the battery pack during use.
  • Fig. 1 is a schematic diagram of an application scenario disclosed in an embodiment of the present application
  • Fig. 2 is a schematic flow chart of a temperature determination method disclosed in an embodiment of the present application
  • Fig. 3a is a schematic diagram of an implementation of step 23 shown in Fig. 2 disclosed in an embodiment of the present application;
  • Fig. 3b is a schematic diagram of another implementation of step 23 shown in Fig. 2 disclosed in an embodiment of the present application;
  • FIG. 4 is a flowchart of a method for determining a current threshold disclosed in an embodiment of the present application
  • Fig. 5a is a schematic diagram of an implementation of step 42 shown in Fig. 4 disclosed in an embodiment of the present application;
  • Fig. 5b is a schematic diagram of another implementation of step 42 shown in Fig. 4 disclosed in an embodiment of the present application;
  • Fig. 5c is a schematic diagram of another embodiment of step 42 shown in Fig. 4 disclosed in an embodiment of the present application;
  • Fig. 5d is a schematic diagram of another embodiment of step 42 shown in Fig. 4 disclosed in an embodiment of the present application;
  • Fig. 6 is a schematic structural diagram of a temperature determining device disclosed in an embodiment of the present application.
  • Fig. 7 is a schematic structural diagram of a device for determining a current threshold disclosed in an embodiment of the present application.
  • Fig. 8 is a schematic structural diagram of a temperature determining device disclosed in another embodiment of the present application.
  • Fig. 9 is a schematic structural diagram of an apparatus for determining a current threshold disclosed in another embodiment of the present application.
  • connection should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; It can be directly connected or indirectly connected through an intermediary.
  • connection should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; It can be directly connected or indirectly connected through an intermediary.
  • the battery is the core of electric vehicles, and it is also a comprehensive embodiment of automotive engineering and power engineering technology. Since the service range of the battery is limited by the service temperature of the battery itself, it is particularly important to detect the real-time temperature of the battery under various working conditions.
  • the inventors of the present application found that in the battery pack, the temperature distribution is uneven. If only by detecting the temperature of multiple locations in the battery pack, and selecting the maximum temperature or the minimum temperature as the current battery pack temperature from the detected temperatures, the battery pack temperature obtained at this time may be different from the actual battery pack temperature at the current moment. If the situation is quite different, the battery cells in the battery pack may be further damaged due to high or low temperature. At the same time, the performance of the battery pack cannot be fully utilized, resulting in a low efficiency of the battery pack.
  • the temperature of the battery pack is also directly related to the current of the battery pack during charging or discharging, for example, the temperature of the battery pack is usually used to determine the current threshold of the battery pack during charging or discharging.
  • the current threshold is also called the allowable current threshold of the battery pack. use current.
  • the allowable current of the battery pack refers to: under the preset voltage and temperature, the battery pack uses the allowable current as the discharge current within the preset time period, and discharges in a constant current discharge method , then the voltage of the battery pack can be equal to the voltage in the undervoltage state at the moment when the preset duration ends.
  • the voltage in the undervoltage state is the upper voltage limit that may cause damage to the battery pack.
  • the battery pack may be damaged.
  • the determined temperature of the battery pack is significantly different from the actual condition of the battery pack at the current moment, it will further cause the determined current threshold to be abnormal.
  • the determined current threshold is too small, the charging or discharging current will be too low, and the performance of the battery pack will not be fully utilized, and the battery pack will have low efficiency; when the determined current threshold is too large, it may cause damage to the battery. damage to the battery pack, shortening the life of the battery pack.
  • the applicant has designed a temperature determination method, which obtains the battery pack temperature at the current moment based on the highest temperature of the battery pack detected at the current moment, the lowest temperature of the battery pack, the over-temperature warning threshold and the under-temperature warning threshold .
  • the temperature of the battery pack can accurately reflect the actual temperature characteristics of the battery pack, thereby reducing the risk of damage to the battery pack, and is also conducive to making full use of the performance of the battery pack, thereby improving the use efficiency of the battery pack.
  • the fault warning threshold including the over-temperature warning threshold and the under-temperature warning threshold
  • it can also reduce false alarms, missed alarms and possible safety risks to protect the battery pack.
  • the applicant also designed a method for determining the current threshold, which combines the voltage or SOC value of the battery cell and the temperature of the battery pack at the current moment.
  • a more appropriate current threshold can be obtained. Controlling the current when the battery pack is charging or discharging based on the current threshold can not only improve the safety of the battery pack during operation to prolong the service life of the battery pack, but also maximize the performance of the battery pack to improve the work of the battery pack. time efficiency.
  • the application scenario includes an electric vehicle 11 and a charging pile 12 .
  • a battery pack 111 is provided in the electric vehicle 11 , and the battery pack 111 can be used to supply power for loads of the electric vehicle 11 .
  • the battery pack 111 includes at least one battery module 1111 and a battery management system 1112 .
  • the battery module 1111 and the battery management system 1112 can be connected through a wire harness, and the wire harness includes a data collection wire harness and a power wire harness.
  • the cell module 1111 includes at least one cell, which is used for charging or discharging, and can be recharged repeatedly in a rechargeable manner.
  • the cells in the cell module 1111 are mainly composed of a positive pole piece, a negative pole piece, a separator, an electrolyte, and a packaging bag.
  • a battery management system (Battery Management System, BMS) 1112 can execute the temperature determination method in any embodiment of the present application, and/or, the current threshold determination method in any embodiment of the present application.
  • the battery management system 1112 includes a control system for protecting the safety of the battery module 1111 for monitoring the usage status of the battery module 1111 .
  • the battery management system 1111 can read the changes in parameters such as voltage, current, and temperature of the battery module 1111 during the charging or discharging process of the battery module 1111, and then can judge in real time whether the battery module 1111 is Abnormal.
  • the battery management system 1112 and the charging pile 12 can be connected via a bus or directly, so that the battery management system 1112 and the charging pile 12 can communicate and transmit data.
  • the battery management system 1112 may send the maximum allowed current, ie, the current threshold, to the charging pile 12, so that the charging pile 12 controls its output charging current to be less than the current threshold.
  • the battery management system 1112 is also connected to the vehicle control unit (Vehicle Control Unit, VCU) in the electric vehicle 11 through a bus, or directly connected to enable communication and data transmission between the battery management system 1112 and the vehicle controller.
  • VCU Vehicle Control Unit
  • the battery management system 1112 can send the current threshold to the vehicle controller (not shown), and the vehicle controller sends it to the charging pile 12, so that the charging pile 12 can control its output charging current less than the current threshold.
  • the battery management system 1112 sends the current threshold to the vehicle controller, so that the vehicle controller controls the electric current of the vehicle to be less than the current threshold by opening or closing the load in the electric vehicle 11 .
  • the electric vehicle is taken as an example of the electric device, while in other embodiments, the electric device can also be an electric motorcycle, an electric bicycle, an electric tool, a drone, a mobile phone, etc. , tablet computer, personal digital assistant, personal computer, energy storage product, or any other suitable device.
  • FIG. 1 is only for illustrating the battery pack 111 .
  • the battery pack 111 may also include more or fewer components, or have different configurations of components, which is not limited in this embodiment of the present application.
  • FIG. 2 is a flow chart of a temperature determination method provided in an embodiment of the present application.
  • the temperature determination method includes the following steps:
  • Step 21 Obtain the highest temperature and the lowest temperature of the battery pack at the current moment.
  • the current moment may correspond to any moment during the charging or discharging process of the battery pack. That is, the highest temperature and the lowest temperature can be obtained at each moment, and the highest temperature obtained at different times may be the same or different, and the lowest temperature obtained at different times may be the same or different.
  • the temperature at least one position (the temperature of these positions is the same) in the battery pack, the temperature is higher than the temperature of other positions, then the temperature of this at least one position is the highest temperature of the battery pack; there is at least one position (these positions) in the battery pack The temperature at the same location) is lower than the temperature at other locations, then the temperature at at least one location is the lowest temperature of the battery pack.
  • At least two temperature sampling points are set in the battery pack, and the temperature sampling point can be set inside or outside the battery pack. Wherein, in one embodiment, when the temperature sampling point is set inside the battery pack, the temperature sampling point can be set on the surface of the battery module in the battery pack.
  • the temperature detected at each temperature sampling point can be correspondingly obtained, and the minimum value of the detected temperature is taken as the lowest temperature, and the maximum value is taken as the highest temperature.
  • the sampling signal can be obtained by setting a temperature sensor at the temperature sampling point.
  • the temperature sensor may be a sensor for detecting temperature such as a thermistor, a thermocouple, or a digital thermometer, which is not limited in this embodiment of the present application.
  • the resistance value of the NTC thermistor decreases as the temperature increases.
  • NTC thermistor can be pasted on a battery module, or can be pasted on a different battery module, The embodiment of the present application does not limit this.
  • the sampling signal can be set as the resistance value of the NTC thermistor, or as the voltage value at both ends of the NTC thermistor, etc.
  • the temperature of each temperature sampling point can be obtained correspondingly .
  • the maximum value among the obtained temperatures of each temperature sampling point is taken as the maximum temperature of the battery pack, and the minimum value is taken as the minimum temperature.
  • the sampling chip can collect the sampling signals of each temperature sampling point, and obtain the corresponding temperature according to the sampling signals.
  • the sampling chip can be integrated on the circuit board of the battery management system; it can also be an independent circuit board, and is connected and communicated with the battery management system through a physical wiring harness to transmit the detected temperature to the battery management system. Among them, after the sampling chip obtains the sampling signal, if the sampling chip detects that it has failed, it will transmit the last obtained temperature to the battery management system; if the sampling chip is normal, it will obtain the temperature according to the current sampling signal and transmit it to the battery management system battery management system.
  • Step 22 Obtain the over-temperature warning threshold and the under-temperature warning threshold.
  • the temperature lower limit is the over-temperature warning threshold.
  • the temperature upper limit is the under-temperature warning threshold.
  • both the over-temperature warning threshold and the under-temperature warning threshold can be set according to actual application scenarios, which are not limited in this embodiment of the present application.
  • different over-temperature warning thresholds and under-temperature warning thresholds are set according to the sensitivity and tolerance of the selected battery chemical system to temperature. For example, for ternary batteries, the The over-temperature warning threshold is set to 55°C, and the under-temperature warning threshold is set to -20°C.
  • Step 23 Determine the battery pack temperature at the current moment according to the highest temperature, the lowest temperature, the over-temperature warning threshold and the under-temperature warning threshold.
  • each moment corresponds to a battery pack temperature
  • the battery pack temperatures corresponding to different moments may be the same or different. Then the temperature of the battery pack at any moment can be obtained through step 23 .
  • the process of determining the battery pack temperature at the current moment in step 23 includes the following specific steps:
  • Step 231 Determine whether the highest temperature is greater than the over-temperature warning threshold.
  • Step 232 If the highest temperature is less than or equal to the over-temperature warning threshold, then determine whether the difference between the highest temperature and the lowest temperature is greater than the first difference.
  • Step 233 If the highest temperature is greater than the over-temperature warning threshold, or the difference between the highest temperature and the lowest temperature is greater than the first difference, determine the highest temperature as the battery pack temperature at the current moment.
  • the first difference may be set according to actual application conditions, which is not specifically limited in this embodiment of the present application.
  • the first difference can be set to 4°C.
  • the highest temperature of the battery pack is greater than the over-temperature warning threshold, or the difference between the highest temperature and the lowest temperature is greater than the first difference, some cells in the battery pack are more likely to be normal. In the working condition of too high temperature, there is a risk of the battery cell being ignited and exploded. At this time, by determining the highest temperature as the battery pack temperature at the current moment, it is beneficial to take corresponding measures in time to reduce the temperature of the battery pack, thereby reducing the probability of damage to the battery cell due to continuous high temperature, so as to damage the battery pack.
  • the bag is for protection.
  • step 231 and step 232 are in a parallel relationship, that is, the order of step 231 and step 232 can be exchanged.
  • step 231 may be performed after step 232 is performed.
  • Step 234 If the maximum temperature is less than or equal to the over-temperature warning threshold, and the difference between the maximum temperature and the minimum temperature is less than or equal to the first difference, then determine whether the minimum temperature is less than the under-temperature warning threshold.
  • Step 235 If the maximum temperature is less than or equal to the over-temperature warning threshold, and the difference between the maximum temperature and the minimum temperature is less than or equal to the first difference, and the minimum temperature is less than the under-temperature warning threshold, determine the minimum temperature as the current battery pack temperature.
  • some of the battery cells in the battery pack are likely to be in a working condition of too low temperature, which may cause irreversible damage to the battery cells.
  • the lowest temperature as the battery pack temperature at the current moment, it is beneficial to reduce the frequency of use of the battery pack when the battery cells in the battery pack are low in energy, so as to reduce the risk of damage to the battery cells due to low temperature and improve the battery life. the life of the battery pack.
  • Step 236 If the maximum temperature is less than or equal to the over-temperature warning threshold, and the difference between the maximum temperature and the minimum temperature is less than or equal to the first difference, and the minimum temperature is greater than or equal to the under-temperature warning threshold, calculate the current The temperature of the battery pack at all times.
  • T0 (( Th-Tmax) ⁇ (Th-(Tl+(Tmax-Tmin)))) ⁇ Tmin+((Tmin-Tl) ⁇ (Th-(Tl+(Tmax-Tmin)))) ⁇ Tmax1.
  • the highest temperature of the battery pack is 17°C
  • the lowest temperature is 15°C
  • the under-temperature warning threshold of the battery cell is set to -20°C
  • the over-temperature warning threshold of the battery cell is set to 55°C.
  • the battery pack is in a normal working condition, that is, the temperature of the battery pack is between the over-temperature warning threshold and the under-temperature warning threshold.
  • the temperature of the battery pack obtained by combining the maximum temperature, the minimum temperature, the over-temperature warning threshold and the under-temperature warning threshold can accurately reflect the actual situation of the battery pack and improve the safety of the battery pack during use.
  • the service life of the battery pack Then, on the basis of maintaining high safety of the battery pack, the performance of the battery pack can be more fully utilized, which is beneficial to improving the use efficiency of the battery pack.
  • the highest temperature of the battery pack, the lowest temperature of the battery pack, the over-temperature warning threshold and the under-temperature warning threshold are obtained at the current moment. Then, according to the magnitude relationship between the maximum temperature and the over-temperature warning threshold, the magnitude relationship between the minimum temperature and the under-temperature warning threshold, and the difference between the maximum temperature and the minimum temperature, the battery pack temperature at the current moment is determined. Not only can the obtained temperature of the battery pack reflect the actual situation of the battery pack more accurately, so as to reduce the risk of damage to the battery pack due to excessively high or low temperature, prolong the use of the battery pack, but also improve the performance of the battery pack. be more fully utilized, thereby improving the efficiency of the battery pack.
  • FIG. 4 is a flowchart of a method for determining a current threshold provided by an embodiment of the present application.
  • the current threshold determination method includes the following steps:
  • Step 41 Obtain the voltage or SOC value of each cell in the battery pack.
  • the SOC (State of Charge) value is the ratio of the remaining capacity of the battery to the nominal capacity of the battery.
  • the SOC value can be obtained through the battery management system.
  • the battery pack includes at least one battery cell, and the battery cells may be connected in series and/or in parallel, wherein the voltage of the battery cell may be the open circuit voltage of the battery cell at the current moment.
  • the voltage of each battery cell can be obtained through a voltage acquisition circuit. In other embodiments, the voltage of each cell can be obtained directly through the battery management system.
  • Step 42 According to the voltage or SOC value of each battery cell and the temperature of the battery pack at the current moment, determine the current threshold when the battery pack is charging or discharging at the current moment.
  • the temperature of the battery pack at the current moment is determined by the highest temperature of the battery pack, the lowest temperature of the battery pack, the over-temperature warning threshold and the under-temperature warning threshold.
  • the temperature of the battery pack at the current moment can be obtained through the method shown in FIG. 2 .
  • the process of determining the current threshold when the battery pack is being charged or discharged at the current moment in step 42 includes the following specific steps:
  • Step 421 If the voltages of all the cells are the same, obtain the voltage of any cell as the first voltage.
  • Step 422 Determine the current threshold according to the first voltage and the current battery pack temperature.
  • the first voltage is the open circuit voltage of any cell in the battery pack at the current moment.
  • the current threshold is the maximum value of the current of the battery pack during charging or discharging.
  • the current threshold can be obtained according to the correspondence among the first voltage, the temperature of the battery pack, and the current threshold.
  • the corresponding relationship among the first voltage, the temperature of the battery pack and the current threshold can be shown in Table 1.
  • the voltage represents the voltage of the cell in V; the temperature represents the temperature of the battery pack in °C; each voltage and temperature corresponds to a current threshold in A.
  • a voltage of 3.359V and a temperature of -5°C correspond to a current threshold of 0.00A; another example, a voltage of 3.359V and a temperature of -4°C corresponds to a current threshold of 0.05A.
  • Linear interpolation is an interpolation method for one-dimensional data, which performs numerical estimation based on two data adjacent to the left and right of the point to be interpolated in the one-dimensional data sequence. For example, suppose the voltage of the cell is 3.600V and the temperature of the battery pack is 16°C. At this time, the current threshold cannot be directly obtained from Table 1. Then the current threshold can be obtained by linear difference.
  • the voltage is 3.600V
  • the process of determining the current threshold when the battery pack is being charged or discharged at the current moment in step 42 includes the following specific steps:
  • Step 423 If the SOC values of all the cells are the same, then acquire the SOC value of any cell as the first SOC value.
  • Step 424 Determine the current threshold according to the first SOC value and the current battery pack temperature.
  • the first SOC value is the SOC value of any cell in the battery pack at the current moment.
  • the current threshold can be obtained according to the correspondence between the first SOC value, the battery pack temperature, and the current threshold.
  • the corresponding relationship among the first voltage, the temperature of the battery pack and the current threshold can be shown in Table 2.
  • the SOC value represents the SOC value of the cell in %; the temperature represents the battery pack temperature in °C; each SOC value and temperature corresponds to a current threshold in A.
  • an SOC value of 10% and a temperature of -4°C correspond to a current threshold of 0.04A; another example, an SOC value of 30% and a temperature of -4°C corresponds to a current threshold of 0.03A.
  • step 421 and step 422 the specific execution process of obtaining the current threshold is similar to step 421 and step 422, which is within the scope of easy understanding by those skilled in the art, and will not be repeated here.
  • the process of determining the current threshold when the battery pack is being charged or discharged at the current moment in step 42 includes the following specific steps:
  • Step 425 If there are at least two voltages with different magnitudes among the voltages of each cell, obtain the maximum voltage and the minimum voltage among the voltages of each cell.
  • Step 426 Determine the current threshold according to the maximum voltage, the minimum voltage and the current battery pack temperature.
  • the maximum voltage, the minimum voltage and the current battery pack temperature can be combined to determine the current threshold, wherein the maximum voltage is the maximum value among the voltages of each cell, and the minimum voltage is the minimum value among the voltages of each cell.
  • the first current threshold can be obtained according to the correspondence between the maximum voltage, the temperature of the battery pack, and the current threshold; and according to the correspondence between the minimum voltage, the temperature of the battery pack, and the current threshold , to obtain the second current threshold. Therefore, the minimum value of the first current threshold and the second current threshold is taken as the current threshold at the current moment.
  • Table 1 As an example for the corresponding relationship among voltage, battery pack temperature, and current threshold. Assume that the maximum voltage of the cells in the battery pack is 3.6V, the minimum voltage is 3.59V, and the temperature of the battery pack is 16°C. It can be known from the above embodiment that the first current threshold is 1.31A, and the second current threshold can be obtained directly from Table 1, which is 1.37A. Since the first current threshold is smaller than the second current threshold, the first current threshold is taken as the current threshold at the current moment, that is, in this embodiment, the current current threshold is determined to be 1.31A.
  • the determined current threshold can more accurately reflect the real ability of the battery pack to charge or discharge, so as to maximize the charging or discharging capacity of the battery pack. current, which can improve the efficiency of the battery pack.
  • controlling the current of the battery pack when charging or discharging through the current threshold is beneficial to reduce the heat generated by the battery cells in the battery pack due to excessive current, which may cause the cells to ignite and cause combustion and explosion. risk.
  • the process of determining the current threshold when the battery pack is being charged or discharged at the current moment in step 42 includes the following specific steps:
  • Step 427 If there are at least two SOC values with different sizes among the SOC values of each battery cell, obtain the maximum SOC value and the minimum SOC value among the SOC values of each battery cell.
  • Step 428 Determine the current threshold according to the maximum SOC value, the minimum SOC value and the current battery pack temperature.
  • the maximum SOC value is the maximum value among the SOC values of each battery cell
  • the minimum SOC value is the minimum value among the SOC values of each battery cell.
  • the third current threshold can be obtained according to the correspondence between the maximum SOC value, the temperature of the battery pack, and the current threshold; and according to the correspondence between the minimum SOC value, the temperature of the battery pack, and the current threshold corresponding relationship to obtain the fourth current threshold. Then, the minimum value of the third current threshold and the fourth current threshold is taken as the current threshold at the current moment.
  • the specific execution process in this embodiment is similar to step 425 and step 426, which are within the scope of easy understanding by those skilled in the art, and will not be repeated here.
  • the battery management system in the battery pack after determining the current threshold at the current moment, sends the current threshold to the charging device or the electric device. Then, the charging device can control its output current to be less than the current threshold, and the electric device can control its power consumption current to be less than the current threshold.
  • the battery pack is used for being charged by the charging device, and for supplying power to the electric device.
  • the power consumption device is an electric vehicle 11
  • the charging device is a charging pile 12 .
  • the battery management system 1112 sends the current threshold value to the vehicle controller in the electric vehicle 11, and the vehicle controller then makes the electric current of the vehicle ( That is, the discharge current of the battery pack) is less than the current threshold.
  • the battery management system 1112 sends the current threshold to the charging pile 12, and the charging pile 12 controls its output current (ie, the charging current of the battery pack) to be smaller than the current threshold.
  • the temperature of the battery pack at the current moment can be determined through the highest temperature of the battery pack at the current moment, the lowest temperature of the battery pack, the over-temperature warning threshold, and the under-temperature warning threshold.
  • the temperature of the battery pack can reflect the actual situation of the battery pack more accurately, thereby reducing the risk of the battery pack being damaged due to excessively high or low temperature, and improving the safety of using the battery pack.
  • the voltage or SOC value of each battery cell in the battery pack determine the current threshold when the battery pack is charging or discharging at the current moment.
  • the current threshold can more accurately reflect the real ability of the battery pack to charge or discharge, thereby increasing the allowable charging or discharging current of the battery pack to improve the use efficiency of the battery pack .
  • controlling the current of the battery pack when charging or discharging through the current threshold is beneficial to reduce the heat generated by the battery cells in the battery pack due to excessive current, which may cause the cells to ignite and cause combustion and explosion. Risk, thus, can prolong the service life of the battery cell.
  • the temperature determination device 600 includes: a temperature acquisition module 601 , an early warning threshold acquisition module 602 and a temperature determination module 603 .
  • the temperature acquiring module 601 is used to acquire the highest temperature and the lowest temperature of the battery pack at the current moment.
  • the warning threshold acquisition module 602 is used to acquire the over-temperature warning threshold and the under-temperature warning threshold.
  • the temperature determining module 603 is used to determine the temperature of the battery pack at the current moment according to the highest temperature, the lowest temperature, the over-temperature warning threshold and the under-temperature warning threshold.
  • the above-mentioned product can execute the method provided by the embodiment of the present application shown in Fig. 2, and has corresponding functional modules and beneficial effects for executing the method.
  • Fig. 2 For technical details not described in detail in this embodiment, refer to the method provided in the embodiment of this application.
  • FIG. 7 shows a schematic structural diagram of a device for determining a current threshold provided by an embodiment of the present application.
  • the device for determining a current threshold 700 includes: a power state acquiring module 701 and a current threshold determining module 702 .
  • the battery status acquisition module 701 is used to acquire the voltage or SOC value of each battery cell in the battery pack, wherein the battery pack includes at least one battery cell, and the SOC value is the ratio of the remaining power of the battery cell to the nominal capacity of the battery cell.
  • the current threshold determination module 702 is used to determine the current threshold when the battery pack is charging or discharging at the current moment according to the voltage or SOC value of each battery cell and the battery pack temperature at the current moment.
  • the temperature of the battery pack at the current moment is determined by the highest temperature of the battery pack, the lowest temperature of the battery pack, the over-temperature warning threshold and the under-temperature warning threshold.
  • the above-mentioned product can execute the method provided by the embodiment of the present application shown in FIG. 4 , and has corresponding functional modules and beneficial effects for executing the method.
  • FIG. 4 For technical details not described in detail in this embodiment, refer to the method provided in the embodiment of this application.
  • FIG. 8 shows a schematic structural diagram of a temperature determination device provided by an embodiment of the present application.
  • the temperature determining device 800 includes one or more processors 801 and memory 802 .
  • one processor 801 is taken as an example in FIG. 8 .
  • the processor 801 and the memory 802 may be connected through a bus or in other ways, and connection through a bus is taken as an example in FIG. 8 .
  • the memory 802 as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs and modules, such as program instructions corresponding to the temperature determination method in the embodiment of the present application /module (for example, each module described in Figure 6).
  • the processor 801 executes various functional applications and data processing of the temperature determination device by running the non-volatile software programs, instructions and modules stored in the memory 802, that is, realizes the temperature determination method and the above-mentioned device in the above-mentioned method embodiments The function of each module of the embodiment.
  • the memory 802 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid-state storage devices.
  • the storage 802 may optionally include storages that are remotely located relative to the processor 801, and these remote storages may be connected to the processor 801 through a network. Examples of the aforementioned networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.
  • the program instructions/modules are stored in the memory 802, and when executed by the one or more processors 801, perform the temperature determination method in any of the above method embodiments, for example, perform the above-described Fig. 2, Fig. 3a and each step shown in FIG. 3b; the functions of each module described in FIG. 6 can also be realized.
  • FIG. 9 shows a schematic structural diagram of an apparatus for determining a current threshold provided by an embodiment of the present application.
  • the device 900 for determining a current threshold includes one or more processors 901 and a memory 902 .
  • one processor 901 is taken as an example in FIG. 9 .
  • the processor 901 and the memory 902 may be connected through a bus or in other ways, and connection through a bus is taken as an example in FIG. 9 .
  • the memory 902 as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs and modules, such as the program corresponding to the current threshold determination method in the embodiment of the present application Instructions/modules (eg, the various modules described in Figure 7).
  • the processor 901 executes various functional applications and data processing of the current threshold determination device by running the non-volatile software programs, instructions and modules stored in the memory 902, that is, realizes the current threshold determination method and the The function of each module of the above device embodiment.
  • the memory 902 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid-state storage devices.
  • the storage 902 may optionally include storages that are remotely located relative to the processor 901, and these remote storages may be connected to the processor 901 through a network. Examples of the aforementioned networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.
  • the program instructions/modules are stored in the memory 902, and when executed by the one or more processors 901, execute the method for determining the current threshold in any of the above method embodiments, for example, execute the above-described Fig. 4,
  • the various steps shown in Fig. 5a, Fig. 5b, Fig. 5c and Fig. 5d; the functions of the various modules described in Fig. 7 can also be realized.
  • An embodiment of the present application further provides a battery management system, including the temperature determining device in any of the above embodiments, and/or the current threshold determining device in any of the above embodiments.
  • An embodiment of the present application also provides a battery pack, including a battery module and the battery management system in any of the above embodiments, the battery management system is electrically connected to the battery module, wherein the battery module includes at least one battery .
  • the embodiment of the present application also provides an electric device, including a load and the battery pack in any of the above embodiments, and the battery pack is used to supply power to the load.
  • the embodiment of the present application also provides a non-volatile computer storage medium, the computer storage medium stores computer-executable instructions, and the computer-executable instructions are executed by one or more processors, which can make the above-mentioned one or more processors
  • the method for determining the temperature in any of the above method embodiments, and/or the method for determining the current threshold may be implemented. For example, each step shown in Fig. 2, Fig. 3a, Fig. 3b, Fig. 4, Fig. 5a, Fig. 5b, Fig. 5c and Fig. 5d described above is executed; each module described in Fig. 6 or Fig. 7 can also be realized function.
  • the device or device embodiments described above are only illustrative, and the unit modules described as separate components may or may not be physically separated, and the components shown as modular units may or may not be physical units , which can be located in one place, or can be distributed to multiple network module units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.
  • each embodiment can be implemented by means of software plus a general hardware platform, and of course also by hardware.
  • the essence of the above technical solutions or the part that contributes to related technologies can be embodied in the form of software products, and the computer software products can be stored in computer-readable storage media, such as ROM/RAM, disk , optical disc, etc., including several instructions for a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments.

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Abstract

本申请实施例提供一种温度确定方法与电流阈值确定方法、电池管理系统，该方法包括获取当前时刻电池包的最高温度与最低温度，获取过温预警阈值与欠温预警阈值，根据最高温度、最低温度、过温预警阈值以及欠温预警阈值，确定当前时刻的电池包温度。通过上述方式，能够提高电池包的使用效率，提升电池包在使用过程的安全性。

Description

温度确定方法与电流阈值确定方法、电池管理系统 技术领域
本申请涉及电池技术领域，特别是涉及一种温度确定方法与电流阈值确定方法、电池管理系统。
背景技术
随着能源问题和环境问题日益严峻，国家对新能源的大力扶持，以及动力电池技术的日益成熟，电动车辆已经成为未来汽车工业发展新方向。电动车辆的续航里程成为影响电动车辆普及的重要因素。作为关键零部件的电池包，是电动车辆的主要动力来源，其产品质量的稳定可靠至关重要。
对于电池包而言，温度为其特征中较为重要的参数。由于电池包中设有多个电芯，所以电池包中的温度通常为分布不均的状态，即电池包中不同位置的温度可能不同。那么，如何选择较为合适的温度作为电池包的当前温度，以较为准确的代表电池包的实际情况，就显得尤为重要。
目前，常用的方式是测量电池包中多个位置的温度，并以最高温度或最低温度作为电池包的当前温度。然而，上述方式会导致电池包的性能无法得到较为充分的利用，降低了电池包的使用效率，并且还存在导致电池包损坏的风险。
发明内容
本申请旨在提供一种温度确定方法与电流阈值确定方法、电池管理系统，能够提高电池包的使用效率，提升电池包在使用过程的安全性。
为实现上述目的，第一方面，本申请提供一种温度确定方法，包括获取当前时刻电池包的最高温度与最低温度。获取过温预警阈值与欠温预警阈值。根据最高温度、最低温度、过温预警阈值以及欠温预警阈值，确定当前时刻的电池包温度。
通过结合最高温度、最低温度、过温预警阈值与欠温预警阈值，所获得的电池包温度，能够较为准确的反应电池包的实际情况，有利于使电池包的性能得到更充分的利用，即能够提高电池包的使用效率。其次，由于结合了过温预警阈值与欠温预警阈值，还能够降低报警的误报、漏报以及可能引发的安全风险，有利于提升电池包在使用过程的安全性。
在一种可选的方式中，在电池包设有至少两个温度采样点。获取当前时刻电池包的最高温度与最低温度，包括：获取各温度采样点的采样信号，并根据采样信号获取当前时刻电池包的最高温度与最低温度。
通过设置多个温度采用点，可获得电池包多个位置的温度，再将所获得的的温度进行比较，其中的最大值即为电池包的最高温度，最小值即为电池包的最低温度。
在一种可选的方式中，根据所述最高温度、最低温度、过温预警阈值以及欠温预警阈值，确定当前时刻的电池包温度，包括：若最高温度大于过温预警阈值，或最高温度与最低温度之间的差值大于第一差值，则确定最高温度为当前时刻的电池包温度。
在该种情况下，电池包中的部分电芯可能处于温度过高的工况。则通过将最高温度确定为当前时刻的电池包温度，有利于后续步骤及时采取相应的措施以降低电池包的温度，即降低电芯的温度，从而，能够降低电芯因持续的温度过高而损坏的风险。
在一种可选的方式中，根据最高温度、最低温度、过温预警阈值以及欠温预警阈值，确定当前时刻的电池包温度，包括：若最高温度小于或等于过温预警阈值，且最高温度与最低温度之间的差值小于或等于第一差值，以及最低温度小于欠温预警阈值，则确定最低温度为当前时刻的电池包温度。
在该种情况下，电池包中的部分电芯可能处于温度过低的工况。则通过将最低温度确定为当前时刻的电池包温度，有利于后续步骤减少对电池包的使用，以降低电池包中电芯因温度过低而损坏的风险，从而提高电池包的使用寿命。
在一种可选的方式中，根据最高温度、最低温度、过温预警阈值以及欠温预警阈值，确定当前时刻的电池包温度，包括：若最高温度小于或等于过温预警阈值，且最高温度与最低温度之间的差值小于或等于第一差值，以及最低温度大于或等于欠温预警阈值，则确定当前时刻的电池包温度为：电池包温度＝((过温预警阈值－最高温度)÷(过温预警阈值－(欠温预警阈值+(最高温度－最低温度))))×最低温度+((最低温度－欠压预警阈值)÷(过温预警阈值－(欠温预警阈值+(最高温度－最低温度))))×最高温度。
在该种情况下，电池包处于正常工况，即电池包的温度处于过温预警阈值与欠温预警阈值之间。此时，通过结合最高温度、最低温度、过温预警阈值与欠温预警阈值所获得的电池包温度，能够较为准确的反应电池包的实际情况，有利于提升电池包在使用过程的安全性。同时，也能够使电池包的性能得到更充分的利用，提高了电池包的使用效率。
第二方面，本申请还提供一种电流阈值确定方法，包括：获取电池包中各电芯的电压或SOC值，其中，电池包包括至少一个电芯，SOC值为电芯剩余电量与电芯标称容量的比值。根据各电芯的电压或SOC值，以及当前时刻的电池包温度，确定当前时刻电池包充电或放电时的电流阈值。其中，当前时刻的电池包温度由电池包的最高温度、电池包的最低温度、过温预警阈值以及欠温预警阈值确定。
一方面，结合最高温度、最低温度、过温预警阈值与欠温预警阈值所获得的电池包温度，能够较为准确的反应电池包的实际情况，以提高电池包使用的安全性。另一方面，进一步通过该电池包温度所确定的电流阈值，能够在保持电池包有较高的安全性的前提下，尽可能提高电池包允许充电或放电的电流，以提高电池包的使用效率。同时，通过该方法所确定的电流阈值也较为符合电池包的充电或放电的真实能力，有利于降低电池包中的电芯因电流过大而产生电芯无法承受的发热热量，并可能引燃电芯，发生燃烧爆炸的风险。
在一种可选的方式中，根据各电芯的电压或SOC值，以及当前时刻的电池包温度，确定当前时刻电池包充电或放电时的电流阈值，包括：若各电芯的电压均相同，则获取任一电芯的电压作为第一电压，并根据第一电压与当前时刻的电池包温度，确定电流阈值。或，若各电芯的SOC值均相同，则获取任一电芯的SOC值作为第一SOC值，并根据第一SOC值与当前时刻的电池包温度，确定电流阈值。
如果电池包中的各电芯的电压或SOC值均相等，那么根据当前时刻任一电芯的电压或SOC值，以及电池包温度，即可确定电流阈值。
在一种可选的方式中，根据各电芯的电压或SOC值，以及当前时刻的电池包温度，确定当前时刻电池包充电或放电时的电流阈值，包括：若各电芯的电压中存在至少两个大小不同的电压，则获取各电芯的电压中的最大电压与最小电压。根据最大电压、最小电压以及当前时刻的电池包温度，确定电流阈值。或，若各电芯的SOC值中存在至 少两个大小不同的SOC值，则获取各电芯的SOC值中的最大SOC值与最小SOC值。根据最大SOC值、最小SOC值以及当前时刻的电池包温度，确定电流阈值。
如果各电芯的电压中存在至少两个大小不同的电压，则必然存在最大电压与最小电压，结合最大电压、最小电压与当前时刻的电池包温度，可确定电流阈值。从而，能够较大程度地提高电池包允许充电或放电的电流，以提高电池包的使用效率。而通过SOC值获取电流阈值的方式与电压类似。
在一种可选的方式中，根据最大电压、最小电压以及当前时刻的电池包温度，确定电流阈值，或，根据最大SOC值、最小SOC值以及当前时刻的电池包温度，确定电流阈值，包括：根据最大电压与当前时刻的电池包温度，获取第一电流阈值。根据最小电压与当前时刻的电池包温度，获取第二电流阈值。将第一电流阈值与第二电流阈值中的最小值作为电流阈值。或，根据最大SOC值与当前时刻的电池包温度，获取第三电流阈值。根据最小SOC值与当前时刻的电池包温度，获取第四电流阈值。将第三电流阈值与第四电流阈值中的最小值作为电流阈值。
可通过查表的方式，获得电压或SOC值、电池包温度以及电流阈值之间的对应关系，即可获得第一电流阈值与第二电流阈值，或者获得第三电流阈值与第四电流阈值，即可确定当前时刻电池包充电或放电时的电流阈值。
在一种可选的方式中，电流阈值确定方法还包括：将电流阈值发送至充电设备或用电设备，以使充电设备控制其充电电流小于电流阈值，或使用电设备控制其用电电流小于电流阈值。其中，电池包用于被充电设备充电，以及用于为用电设备供电。
第三方面，本申请还提供一种温度确定装置，包括：温度获取模块，用于获取当前时刻电池包的最高温度与最低温度。预警阈值获取模块，用于获取过温预警阈值与欠温预警阈值。温度确定模块，用于根据最高温度、最低温度、过温预警阈值以及欠温预警阈值，确定当前时刻的电池包温度。
第四方面，本申请还提供一种电流阈值确定装置，包括：电量状态获取模块，用于获取电池包中各电芯的电压或SOC值，其中，电池包包括至少一个电芯，SOC值为电芯剩余电量与电芯标称容量的比值。电流阈值确定模块，用于根据各电芯的电压或SOC值，以及当前时刻的电池包温度，确定当前时刻电池包充电或放电时的电流阈值。其中，当前时刻的电池包温度由电池包的最高温度、电池包的最低温度、过温预警阈值以及欠温预警阈值确定。
第五方面，本申请还提供一种温度确定装置，包括：存储器；以及耦接至存储器的处理器，处理器被配置为基于存储在存储器中的指令，执行如第一方面中的方法。
第六方面，本申请还提供一种电流阈值确定装置，包括：存储器；以及耦接至存储器的处理器，处理器被配置为基于存储在存储器中的指令，执行如第二方面中的方法。
第七方面，本申请还提供一种电池管理系统，包括如第三方面或第五方面中的温度确定装置，和/或，如第四方面或第六方面中的电流阈值确定装置。
第八方面，本申请还提供一种电池包，包括电芯模组以及如上的电池管理系统，电池管理系统与电芯模组电连接，其中，电芯模组包括至少一个电芯。
第九方面，本申请还提供一种用电设备，包括负载以及如第八方面中的电池包，电池包用于为负载供电。
第十方面，本申请还提供一种计算机可读存储介质，包括：存储有计算机可执行指令，所述计算机可执行指令设置为如第一方面与第二方面中的方法流程。
本申请实施例的有益效果是：本申请所提供的温度确定方法，包括获取当前时刻电池包的最高温度与最低温度，以及获取过温预警阈值与欠温预警阈值，并根据最高温度、最低温度、过温预警阈值以及欠温预警阈值，确定当前时刻的电池包温度。本申 请通过结合最高温度、最低温度、过温预警阈值与欠温预警阈值，所获得的电池包温度，能够较为准确的反应电池包的实际情况，有利于使电池包的性能得到更充分的利用，从而，能够提高电池包的使用效率。同时，由于结合了过温预警阈值与欠温预警阈值，还能够降低报警的误报、漏报以及可能引发的安全风险，从而提升电池包在使用过程的安全性。
附图说明
为了更清楚地说明本申请实施例的技术方案，下面将对本申请实施例中所需要使用的附图作简单地介绍，显而易见地，下面所描述的附图仅仅是本申请的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据附图获得其他的附图。
图1是本申请一实施例公开的一种应用场景的示意图；
图2是本申请一实施例公开的温度确定方法的流程示意图；
图3a是本申请一实施例公开的图2中示出的步骤23的一实施方式的示意图；
图3b是本申请一实施例公开的图2中示出的步骤23的另一实施方式的示意图；
图4是本申请一实施例公开的电流阈值确定方法的流程图；
图5a是本申请一实施例公开的图4中示出的步骤42的一实施方式的示意图；
图5b是本申请一实施例公开的图4中示出的步骤42的另一实施方式的示意图；
图5c是本申请一实施例公开的图4中示出的步骤42的又一实施方式的示意图；
图5d是本申请一实施例公开的图4中示出的步骤42的又一实施方式的示意图；
图6是本申请一实施例公开的温度确定装置的结构示意图；
图7是本申请一实施例公开的电流阈值确定装置的结构示意图；
图8是本申请另一实施例公开的温度确定装置的结构示意图；
图9是本申请另一实施例公开的电流阈值确定装置的结构示意图。
在附图中，附图并未按照实际的比例绘制。
具体实施方式
下面结合附图和实施例对本申请的实施方式作进一步详细描述。以下 实施例的详细描述和附图用于示例性地说明本申请的原理，但不能用来限制本申请的范围，即本申请不限于所描述的实施例。
在本申请的描述中，需要说明的是，除非另有说明，“多个”的含义是两个以上；术语“上”、“下”、“左”、“右”、“内”、“外”等指示的方位或位置关系仅是为了便于描述本申请和简化描述，而不是指示或暗示所指的装置或元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本申请的限制。此外，术语“第一”、“第二”、“第三”等仅用于描述目的，而不能理解为指示或暗示相对重要性。
下述描述中出现的方位词均为图中示出的方向，并不是对本申请的具体结构进行限定。在本申请的描述中，还需要说明的是，除非另有明确的规定和限定，术语“连接”应做广义理解，例如，可以是固定连接，也可以是可拆卸连接，或一体地连接；可以是直接相连，也可以通过中间媒介间接相连。对于本领域的普通技术人员而言，可视具体情况理解上述术语在本申请中的具体含义。
近几年，新能源汽车行业迎来了爆发式增长。电池是电动汽车的核心，也是汽车工程与电力工程技术的综合体现。由于电池的使用范围受到电池本身的使用温度限制，因此，对电池在各种工况下的实时温度检测尤为重要。
本申请的发明人在实现本申请的过程中，发现：在电池包中，温度分布不均。如果仅通过检测电池包中多个位置的温度，并在所检测到的温度中选择最大温度或最小温度作为当前时刻的电池包温度，此时所获得电池包温度可能与当前时刻电池包的实际情况差别较大，则有可能会进一步导致电池包中的电芯因温度过高或温度过低而损坏，同时，电池包的性能也无法得到充分的利用，导致电池包的使用效率较低。
其次，由于电池包温度还与电池包在充电或放电过程中的电流直接相关，例如，电池包温度通常用于确定电池包在充电或放电时的电流阈值，电流阈值也称为电池包的允许使用电流。以电池包放电为例，电池包允许使用的电流指：在预设的电压和温度下，电池包在预设时长内以该允许使用的电流作为放电电流，并采用恒定电流放电的方式进行放电，则能够在预设时长结束的时刻使电池包的电压等于欠压状态时的电压。其中，欠压状态的电压为可能导致电池包损坏的电压上限，换言之，在放电过程中，若电池包的 电压减小至小于欠压状态的电压，则电池包可能会损坏。同时，若所确定的电池包温度与当前时刻电池包的实际情况差别较大，还会进一步导致所确定的电流阈值异常。当确定的电流阈值过小时，会导致充电或放电时的电流过低，则电池包的性能无法充分发挥，电池包的使用效率较低；当确定的电流阈值过大时，则可能导致对电池包造成损伤，缩短了电池包的使用寿命。
基于此，申请人设计了一种温度确定方法，该方法基于当前时刻所检测到的电池包的最高温度、电池包的最低温度、过温预警阈值与欠温预警阈值获得当前时刻的电池包温度。该电池包温度能够较为准确的反应电池包的实际温度特征，从而降低电池包被损坏的风险，并且，也有利于使电池包的性能得到更充分的利用，从而提高了电池包的使用效率。同时，由于结合了故障预警阈值(包括过温预警阈值与欠温预警阈值)，还能够降低报警的误报、漏报以及可能引发的安全风险，以对电池包起到保护作用。
进一步地，申请人还设计了一种电流阈值确定方法，该方法结合电芯的电压或SOC值、以及当前时刻的电池包温度。当所获得的当前时刻的电池包温度准确度较高时，比如通过上述的温度确定方法所获得的电池包温度，则能够获得较为合适的电流阈值。基于该电流阈值控制电池包充电或放电时的电流，不仅能够提升电池包工作时的安全性，以延长电池包的使用寿命，还能够较大程度地发挥电池包的性能，以提升电池包工作时的效率。
为了便于理解本申请，首先介绍下本申请一种可以适用的应用场景，如图1所示，在该应用场景中包括电动车辆11与充电桩12。其中，在电动汽车11中设置有电池包111，电池包111可用于为电动车辆11的负载供电。电池包111包括至少一个电芯模组1111，以及电池管理系统1112。电芯模组1111与电池管理系统1112之间可以通过线束连接，线束包括数据采集线束以及功率线束。电芯模组1111包括至少一个电芯，电芯用于充电或放电，且可以采用可循环再充电的方式反复充电。在一实施例中，电芯模组1111中的电芯主要由正极极片、负极极片、隔离膜、电解液以及包装袋组成。
电池管理系统(Battery Management System，BMS)1112能够执行本申请任一实施例中的温度确定方法，和/或，本申请任一实施例中的电流阈值确定方法。电池管理系统1112包括一套保护电芯模组1111使用安全的控制系统，用于监控电芯模组1111的使用状态。例如，电池管理系统 1111能够在电芯模组1111充电或放电的过程中，读取电芯模组1111的电压、电流、温度等参数的变化情况，继而，可实时判断电芯模组1111是否出现异常。
电池管理系统1112与充电桩12可通过总线连接，也可以直接连接，以使电池管理系统1112与充电桩12之间进行通讯以及数据传输。例如，在充电过程中，电池管理系统1112可将允许使用的最大电流，即电流阈值发送至充电桩12，以使充电桩12控制其输出的充电电流小于该电流阈值。
电池管理系统1112还与电动车辆11中的整车控制器(Vehicle Control Unit,VCU)通过总线连接，或者直接连接，以使电池管理系统1112与整车控制器之间进行通讯以及数据传输。例如，在充电过程中，电池管理系统1112可将电流阈值发送至整车控制器(图未示)，并由整车控制器发送至充电桩12，以使充电桩12控制其输出的充电电流小于该电流阈值。又如，电池管理系统1112将电流阈值发送至整车控制器，以使整车控制器通过断开或闭合电动车辆11中的负载的方式，控制整车的用电电流小于电流阈值。
需要说明的是，在该实施例中，是以用电设备为电动车辆为例，而在其他的实施例中，用电设备还可以为电动摩托、电动单车、电动工具、无人机、手机、平板电脑、个人数字助理、个人电脑、储能产品，或者任何其他适合的装置。
其次，图1仅为举例说明电池包111。在其他的实施例中，电池包111也可以包括更多或更少的元件，或者具有不同的元件配置，本申请实施例对此不作限制。
请参阅图2，图2为本申请实施例提供的温度确定方法的流程图。该温度确定方法包括以下步骤：
步骤21：获取当前时刻电池包的最高温度与最低温度。
其中，当前时刻可对应电池包在充电或放电过程中的任一时刻。即每一个时刻均能够获取到最高温度与最低温度，并且，不同时刻所获取的最高温度可能相同也可能不同，不同时刻所获取的最低温度可能相同也可能不同。
同时，在电池包中存在至少一个位置(这些位置的温度相同)的温 度高于其他位置的温度，则该至少一个位置的温度为电池包的最高温度；在电池包中存在至少一个位置(这些位置的温度相同)的温度小于其他位置的温度，则该至少一个位置的温度为电池包的最低温度。
在一实施例中，在电池包中设有至少两个温度采样点，温度采用点可设于电池包的内部或外部。其中，在一实施方式中，当温度采样点设于电池包内部时，可将温度采样点设于电池包中电芯模组的表面。
继而，通过获取各温度采样点的采样信号，则可对应获得在各温度采样点所检测到的温度，并取所检测到的温度的最小值作为最低温度，以及最大值作为最高温度。
可以理解的是，可通过在温度采样点设置温度传感器以获得采样信号。其中，温度传感器可以为热敏电阻、热电偶或数字温度计等用于检测温度的传感器，本申请实施例对此不作限制。
以采用负温度系数(Negative Temeprature Coefficient，NTC)热敏电阻，且温度采样点设于电池包的内部为例进行说明，其中，NTC热敏电阻的电阻值随温度的升高而减小。具体地，将至少两个NTC热敏电阻贴于电池包中电芯模组的表面，其中，可将各NTC热敏电阻贴于一电芯模组，也可以贴于不同电芯模组，本申请实施例对此不作限制。进而，采样信号可设置为NTC热敏电阻的电阻值，或设置为NTC热敏电阻两端的电压值等，通过获取到各NTC热敏电阻的采样信号，即可对应获得各温度采样点的温度。将所获得的各温度采样点的温度中的最大值作为电池包的最高温度，最小值作为最低温度。
在一实施方式中，可通过采样芯片采集各温度采样点的采样信号，并根据采样信号获得对应的温度。采样芯片可集成于电池管理系统的电路板上；也可为一独立的电路板，并通过实体线束与电池管理系统进行连接与通讯，以将所检测到的温度传输至电池管理系统。其中，在采样芯片获得采样信号后，若采样芯片检测到自身发生故障，则将上一个所获得的温度传输至电池管理系统；若采样芯片正常，则根据当前时刻的采样信号获得温度后传输至电池管理系统。
步骤22：获取过温预警阈值与欠温预警阈值。
当电池包中电芯的温度过高时，由于电芯内部为锂等易燃金属，若继续使用电芯可能导致温度进一步上升，进而可能导致电芯燃烧。针对该种 情况，可设置可能导致电芯燃烧的温度下限，当达到该温度下限时进行报警提示，以停止使用电芯，对电芯起到保护作用。其中，该温度下限即为过温预警阈值。
当电芯温度过低时，电芯的活性较低，若继续对电芯进行充电或放电会导致对电芯造成不可逆的损坏。针对该种情况，可设置可能对电芯造成不可逆的损坏的温度上限，当达到该温度上限时进行报警提示，以停止使用电芯，对电芯起到保护作用。其中，该温度上限即为欠温预警阈值。
需要说明的是，过温预警阈值与欠温预警阈值均可根据实际应用场景进行设置，本申请实施例对此不作限制。例如，在一实施例中，根据所选用的电芯化学体系对温度的敏感和耐受程度不同而设置不同的过温预警阈值与欠温预警阈值，比如对于三元电芯而言，可将过温预警阈值设置为55℃，并将欠温预警阈值设置为-20℃。
步骤23：根据最高温度、最低温度、过温预警阈值以及欠温预警阈值，确定当前时刻的电池包温度。
其中，每一个时刻均对应一电池包温度，并且，不同时刻所对应的电池包温度可能相同也可能不同。则通过步骤23可获得任一时刻的电池包温度。
在一实施例中，如图3所示，步骤23中确定当前时刻的电池包温度的过程包括如下具体步骤：
步骤231：判断最高温度是否大于过温预警阈值。
步骤232：若最高温度小于或等于过温预警阈值，则判断最高温度与最低温度之间的差值是否大于第一差值。
步骤233：若最高温度大于过温预警阈值，或最高温度与最低温度之间的差值大于第一差值，则确定最高温度为当前时刻的电池包温度。
其中，第一差值可根据实际应用情况进行设置，本申请实施例对此不做具体限定。例如，第一差值可设置为4℃。
在此实施例中，无论是电池包的最高温度大于过温预警阈值，还是最高温度与最低温度之间的差值大于第一差值，电池包中部分电芯均有较大的可能性正处于温度过高的工况，存在电芯被燃爆的风险。此时，通过将最高温度确定为当前时刻的电池包温度，有利于及时采取相应的措施以降低电池包的温度，从而，能够降低电芯因持续的温度过高而损坏的几率，以对电 池包起到保护作用。
可以理解的是，步骤231与步骤232为并列关系，即步骤231与步骤232之间的顺序可以调换。例如，如图3b所示，可以在执行步骤232之后再执行步骤231。
步骤234：若最高温度小于或等于过温预警阈值，且最高温度与最低温度之间的差值小于或等于第一差值，则判断最低温度是否小于欠温预警阈值。
步骤235：若最高温度小于或等于过温预警阈值，且最高温度与最低温度之间的差值小于或等于第一差值，以及最低温度小于欠温预警阈值，则确定最低温度为当前时刻的电池包温度。
在此实施例中，电池包中部分电芯有较大的可能性正处于温度过低的工况，可能导致电芯受到不可逆的损坏。此时，通过将最低温度确定为当前时刻的电池包温度，有利于在电池包中电芯活力较低时减少对电池包的使用频率，以降低电芯因温度过低而损坏的风险，提高了电池包的使用寿命。
步骤236：若最高温度小于或等于过温预警阈值，且最高温度与最低温度之间的差值小于或等于第一差值，以及最低温度大于或等于欠温预警阈值，则通过公式计算获得当前时刻的电池包温度。
在一实施例中，假设过温预警阈值为Th，欠温预警阈值为Tl，最高温度为Tmax，最低温度为Tmin，即可通过以下公式计算当前时刻的电池包温度T0为：T0＝((Th－Tmax)÷(Th－(Tl+(Tmax－Tmin))))×Tmin+((Tmin－Tl)÷(Th－(Tl+(Tmax－Tmin))))×Tmax①。例如，假设当前时刻，电池包的最高温度为17℃，最低温度为15℃，且电芯的欠温预警阈值设定为-20℃，电芯的过温预警阈值设定为55℃。由公式①可得，当前时刻的电池包温度T0＝((55－17)÷(55－((-20)+(17－15))))×15+((15－(-20))÷(55－((-20)+(17－15))))×17＝15.96℃。
在此实施例中，电池包处于正常工况，即电池包的温度处于过温预警阈值与欠温预警阈值之间。此时，通过结合最高温度、最低温度、过温预警阈值与欠温预警阈值所获得的电池包温度，能够较为准确的反应电池包的实际情况，提升了电池包使用过程的安全性，以延长电池包的使用寿命。继而，可实现在保持电池包有较高的安全性的基础上，使电池包的性能得到更充分的利用，有利于提高了电池包的使用效率。
在上述实施例中，首先获取当前时刻电池包的最高温度、电池包的最低温度、过温预警阈值以及欠温预警阈值。继而，根据最高温度与过温预警阈值之间的大小关系、最低温度与欠温预警阈值之间的大小关系、以及最高温度与最低温度之间的差值，确定当前时刻的电池包温度。不仅能够使所获得的电池包温度较为准确的反应电池包的实际情况，以降低电池包因温度过高或过低而被损坏的风险，延长电池包的使用手，还能够使电池包的性能得到更充分的利用，从而提高了电池包的使用效率。
请参阅图4，图4为本申请实施例提供的电流阈值确定方法的流程图。该电流阈值确定方法包括以下步骤：
步骤41：获取电池包中各电芯的电压或SOC值。
其中，SOC(State of Charge)值为电芯剩余容量与电芯标称容量的比值。SOC值可通过电池管理系统获取得到。
电池包包括至少一个电芯，各电芯之间可以为串联和/或并联连接，其中，电芯的电压可为电芯在当前时刻的开路电压。在一实施例中，可通过电压采集回路获取各电芯的电压。在其他的实施例中，各电芯的电压可通过电池管理系统直接获取得到。
步骤42：根据各电芯的电压或SOC值，以及当前时刻的电池包温度，确定当前时刻电池包充电或放电时的电流阈值。
其中，当前时刻的电池包温度由电池包的最高温度、电池包的最低温度、过温预警阈值以及欠温预警阈值确定。例如，可通过图2所示的方法获得当前时刻的电池包温度。
在一实施例中，如图5a所示，步骤42中确定当前时刻电池包充电或放电时的电流阈值的过程包括如下具体步骤：
步骤421：若各电芯的电压均相同，则获取任一电芯的电压作为第一电压。
步骤422：根据第一电压与当前时刻的电池包温度，确定电流阈值。
其中，第一电压为当前时刻电池包中任一电芯的开路电压。电流阈值为电池包在充电过程或放电过程中的电流的最大值。
在一实施例中，在获取到第一电压与电池包温度后，可根据第一电压、电池包温度以及电流阈值三者之间的对应关系，以获得电流阈值。其 中，第一电压、电池包温度以及电流阈值三者之间的对应关系可如表1所示。
表1
Figure PCTCN2021115473-appb-000001
如表1所示，其中，电压表示电芯的电压，单位为V；温度表示电池包温度，单位为℃；每一个电压与温度对应一个电流阈值，单位为A。例如，电压3.359V与温度-5℃对应电流阈值0.00A；又如，电压3.359V与温度-4℃对应电流阈值0.05A。
可以理解的是，对于不同的电池体系或电池采用不同的材料或根据电池具有不同的特性，电压、电池包温度以及电池阈值之间的对应关系可能相同也可能不同，本申请实施例对此不做具体限定。
进一步地，若电流阈值无法从表1中直接获得，则可采用线性差值的方式获得。线性插值是针对一维数据的插值方法，其根据一维数据序列中需要插值的点的左右临近两个数据来进行数值估计。比如，假设电芯的电压为3.600V，电池包温度为16℃，此时，无法直接由表1获得电流阈值。则可采用线性差值的方式获得电流阈值，具体地，由于3.600V大于3.59V且小于3.637V，则取3.59V(在16℃对应电流阈值为1.37A)与3.637V(在16℃对应电流阈值为1.07A)这两个点进行估算，则电压为3.600V，且电池包温度为16℃时的电流阈值为：1.37－(1.37－1.07)÷(3.637－3.590)×(3.600-3.590)＝1.31A。亦即，当电芯的电压为3.600V，电池包温度为16℃时，电流阈值为1.31A。
在另一实施例中，如图5b所示，步骤42中确定当前时刻电池包充电或放电时的电流阈值的过程包括如下具体步骤：
步骤423：若各电芯的SOC值均相同，则获取任一电芯的SOC值作为第一SOC值。
步骤424：根据第一SOC值与当前时刻的电池包温度，确定电流阈值。
其中，第一SOC值为当前时刻电池包中任一电芯的SOC值。同样地，若获得第一SOC值与当前时刻的电池包温度，则可根据第一SOC值、电池包温度以及电流阈值之间的对应关系，获得电流阈值。其中，第一电压、电池包温度以及电流阈值三者之间的对应关系可如表2所示。
表2
Figure PCTCN2021115473-appb-000002
Figure PCTCN2021115473-appb-000003
如表2所示，其中，SOC值表示电芯的SOC值，单位为％；温度表示电池包温度，单位为℃；每一个SOC值与温度对应一个电流阈值，单位为A。例如，SOC值为10％与温度-4℃对应电流阈值0.04A；又如，SOC值为30％与温度-4℃对应电流阈值0.03A。
在此实施例中，获得电流阈值的具体执行过程与步骤421以及步骤422类似，其在本领域技术人员容易理解的范围内，这里不再赘述。
在一实施例中，如图5c所示，步骤42中确定当前时刻电池包充电或放电时的电流阈值的过程包括如下具体步骤：
步骤425：若各电芯的电压中存在至少两个大小不同的电压，则获取各电芯的电压中的最大电压与最小电压。
步骤426：根据最大电压、最小电压以及当前时刻的电池包温度，确定电流阈值。
若各电芯的电压中存在至少两个大小不同的电压，则必然存在最大电压与最小电压。继而，可结合最大电压、最小电压与当前时刻的电池包温 度，以确定电流阈值，其中，最大电压为各电芯的电压中的最大值，最小电压为各电芯的电压中的最小值。
在一实施例中，可根据最大电压、电池包温度以及电流阈值三者之间的对应关系，以获得第一电流阈值；并根据最小电压、电池包温度以及电流阈值三者之间的对应关系，以获得第二电流阈值。从而，将第一电流阈值与第二电流阈值中的最小值最为当前时刻的电流阈值。
仍以电压、电池包温度以及电流阈值之间的对应关系为表1为例。假设当前时刻电池包中电芯的最大电压为3.6V，最小电压为3.59V，电池包温度为16℃。由上述实施例可知，第一电流阈值为1.31A，第二电流阈值则可直接从表1中获取，为1.37A。由于第一电流阈值小于第二电流阈值，则将第一电流阈值作为当前时刻的电流阈值，即在此实施例中，当前电流阈值确定为1.31A。
在此实施例中，通过结合最大电压、最小电压与当前时刻的电池包温度，所确定的电流阈值可较为准确地反应电池包充电或放电的真实能力，以尽可能提高电池包允许充电或放电的电流，从而能够提高电池包的使用效率。此外，通过该电流阈值控制电池包充电或放电时的电流，有利于降低电池包中的电芯因电流过大而产生电芯无法承受的发热热量，并可能引燃电芯，发生燃烧爆炸的风险。
在另一实施例中，如图5d所示，步骤42中确定当前时刻电池包充电或放电时的电流阈值的过程包括如下具体步骤：
步骤427：若各电芯的SOC值中存在至少两个大小不同的SOC值，则获取各电芯的SOC值中的最大SOC值与最小SOC值。
步骤428：根据最大SOC值、最小SOC值以及当前时刻的电池包温度，确定电流阈值。
其中，最大SOC值为各电芯的SOC值中的最大值，最小SOC值为各电芯的SOC值中的最小值。
在一实施方式中，可根据最大SOC值、电池包温度以及电流阈值三者之间的对应关系，以获得第三电流阈值；并根据最小SOC值、电池包温度以及电流阈值三者之间的对应关系，以获得第四电流阈值。继而，将第三电流阈值与第四电流阈值中的最小值最为当前时刻的电流阈值。此实施方式中的具体执行过程与步骤425以及步骤426类似，其在本领域技术人员容易理 解的范围内，这里不再赘述。
在一实施例中，在确定当前时刻的电流阈值之后，电池包中的电池管理系统将该电流阈值发送至充电设备或用电设备。继而，充电设备可控制其输出电流小于该电流阈值，用电设备可控制其用电电流小于该电流阈值。其中，电池包用于被充电设备充电，以及用于为用电设备供电。
以图1所示的应用场景为例，此时，用电设备为电动车辆11，充电设备为充电桩12。在放电过程中，电池管理系统1112将电流阈值发送至电动车辆11中的整车控制器，整车控制器再通过断开或闭合电动车辆11中负载的方式，使整车的用电电流(即电池包的放电电流)小于电流阈值。在充电过程中，电池管理系统1112将电流阈值发送至充电桩12，充电桩12控制其输出的电流(即电池包的充电电流)小于电流阈值。
综上，在本申请的实施例中，首先，可通过当前时刻电池包的最高温度、电池包的最低温度、过温预警阈值以及欠温预警阈值，确定当前时刻的电池包温度。该电池包温度能够较为准确的反应电池包的实际情况，从而，降低电池包因温度过高或过低而被损坏的风险，提高电池包使用的安全性。其次，再根据该电池包温度、电池包中各电芯的电压或SOC值，确定当前时刻电池包充电或放电时的电流阈值。在保持电池包有较高的安全性的前提下，该电流阈值能够较为准确地反应电池包充电或放电的真实能力，从而能够提高电池包允许充电或放电的电流，以提高电池包的使用效率。此外，通过该电流阈值控制电池包充电或放电时的电流，有利于降低电池包中的电芯因电流过大而产生电芯无法承受的发热热量，并可能引燃电芯，发生燃烧爆炸的风险，从而，能够延长电芯的使用寿命。
请参见图6，其示出了本申请实施例提供的一种温度确定装置的结构示意图，温度确定装置600包括：温度获取模块601、预警阈值获取模块602及温度确定模块603。
温度获取模块601用于获取当前时刻电池包的最高温度与最低温度。
预警阈值获取模块602用于获取过温预警阈值与欠温预警阈值。
温度确定模块603用于根据最高温度、最低温度、过温预警阈值以及欠温预警阈值，确定当前时刻的电池包温度。
上述产品可执行图2所示的本申请实施例所提供的方法，具备执行 方法相应的功能模块和有益效果。未在本实施例中详尽描述的技术细节，可参见本申请实施例所提供的方法。
请参见图7，其示出了本申请实施例提供的一种电流阈值确定装置的结构示意图，电流阈值确定装置700包括：电量状态获取模块701与电流阈值确定模块702。
电量状态获取模块701用于获取电池包中各电芯的电压或SOC值，其中，电池包包括至少一个电芯，SOC值为电芯剩余电量与电芯标称容量的比值。
电流阈值确定模块702用于根据各电芯的电压或SOC值，以及当前时刻的电池包温度，确定当前时刻电池包充电或放电时的电流阈值。
其中，当前时刻的电池包温度由电池包的最高温度、电池包的最低温度、过温预警阈值以及欠温预警阈值确定。
上述产品可执行图4所示的本申请实施例所提供的方法，具备执行方法相应的功能模块和有益效果。未在本实施例中详尽描述的技术细节，可参见本申请实施例所提供的方法。
请参见图8，其示出本申请实施例提供一种温度确定装置的结构示意图。如图8所示，该温度确定装置800包括一个或多个处理器801以及存储器802。其中，图8中以一个处理器801为例。
处理器801和存储器802可以通过总线或者其他方式连接，图8中以通过总线连接为例。
存储器802作为一种非易失性计算机可读存储介质，可用于存储非易失性软件程序、非易失性计算机可执行程序以及模块，如本申请实施例中的温度确定方法对应的程序指令/模块(例如，附图6所述的各个模块)。处理器801通过运行存储在存储器802中的非易失性软件程序、指令以及模块，从而执行温度确定装置的各种功能应用以及数据处理，即实现上述方法实施例中的温度确定方法以及上述装置实施例的各个模块的功能。
存储器802可以包括高速随机存取存储器，还可以包括非易失性存储器，例如至少一个磁盘存储器件、闪存器件、或其他非易失性固态存储器件。在一些实施例中，存储器802可选包括相对于处理器801远程设置的存储器，这些远程存储器可以通过网络连接至处理器801。上述网络的实例包括但不限于互联网、企业内部网、局域网、移动通信网及其组合。
所述程序指令/模块存储在所述存储器802中，当被所述一个或者多个处理器801执行时，执行上述任意方法实施例中的温度确定方法，例如，执行以上描述的图2、图3a和图3b所示的各个步骤；也可实现附图6所述的各个模块的功能。
请参见图9，其示出本申请实施例提供一种电流阈值确定装置的结构示意图。如图9所示，该电流阈值确定装置900包括一个或多个处理器901以及存储器902。其中，图9中以一个处理器901为例。
处理器901和存储器902可以通过总线或者其他方式连接，图9中以通过总线连接为例。
存储器902作为一种非易失性计算机可读存储介质，可用于存储非易失性软件程序、非易失性计算机可执行程序以及模块，如本申请实施例中的电流阈值确定方法对应的程序指令/模块(例如，附图7所述的各个模块)。处理器901通过运行存储在存储器902中的非易失性软件程序、指令以及模块，从而执行电流阈值确定装置的各种功能应用以及数据处理，即实现上述方法实施例中的电流阈值确定方法以及上述装置实施例的各个模块的功能。
存储器902可以包括高速随机存取存储器，还可以包括非易失性存储器，例如至少一个磁盘存储器件、闪存器件、或其他非易失性固态存储器件。在一些实施例中，存储器902可选包括相对于处理器901远程设置的存储器，这些远程存储器可以通过网络连接至处理器901。上述网络的实例包括但不限于互联网、企业内部网、局域网、移动通信网及其组合。
所述程序指令/模块存储在所述存储器902中，当被所述一个或者多个处理器901执行时，执行上述任意方法实施例中的电流阈值确定方法，例如，执行以上描述的图4、图5a、图5b、图5c和图5d所示的各个步骤；也可实现附图7所述的各个模块的功能。
本申请实施例还提供一种电池管理系统，包括上述任一实施例中的温度确定装置，和/或，上述任一实施例中的电流阈值确定装置。
本申请实施例还提供一种电池包，包括电芯模组以及上述任一实施例中的电池管理系统，电池管理系统与电芯模组电连接，其中，电芯模组包括至少一个电芯。
本申请实施例还提供一种用电设备，包括负载以及上述任一实施例 中的电池包，电池包用于为负载供电。
本申请实施例还提供了一种非易失性计算机存储介质，计算机存储介质存储有计算机可执行指令，该计算机可执行指令被一个或多个处理器执行，可使得上述一个或多个处理器可执行上述任意方法实施例中的温度确定方法，和/或，电流阈值确定方法。例如，执行以上描述的图2、图3a、图3b、图4、图5a、图5b、图5c和图5d所示的各个步骤；也可实现附图6或附图7所述的各个模块的功能。
以上所描述的装置或设备实施例仅仅是示意性的，其中所述作为分离部件说明的单元模块可以是或者也可以不是物理上分开的，作为模块单元显示的部件可以是或者也可以不是物理单元，即可以位于一个地方，或者也可以分布到多个网络模块单元上。可以根据实际的需要选择其中的部分或者全部模块来实现本实施例方案的目的。
通过以上的实施方式的描述，本领域的技术人员可以清楚地了解到各实施方式可借助软件加通用硬件平台的方式来实现，当然也可以通过硬件。基于这样的理解，上述技术方案本质上或者说对相关技术做出贡献的部分可以以软件产品的形式体现出来，该计算机软件产品可以存储在计算机可读存储介质中，如ROM/RAM、磁碟、光盘等，包括若干指令用于一台计算机设备(可以是个人计算机，服务器，或者网络设备等)执行各个实施例或者实施例的某些部分所述的方法。
虽然已经参考优选实施例对本申请进行了描述，但在不脱离本申请的范围的情况下，可以对其进行各种改进并且可以用等效物替换其中的部件。尤其是，只要不存在结构冲突，各个实施例中所提到的各项技术特征均可以任意方式组合起来。本申请并不局限于文中公开的特定实施例，而是包括落入权利要求的范围内的所有技术方案。

Claims (18)

  1. 一种温度确定方法，包括：
    获取当前时刻电池包的最高温度与最低温度；
    获取过温预警阈值与欠温预警阈值；
    根据所述最高温度、所述最低温度、所述过温预警阈值以及所述欠温预警阈值，确定当前时刻的电池包温度。
  2. 根据权利要求1所述的温度确定方法，其中，在所述电池包设有至少两个温度采样点；
    所述获取当前时刻电池包的最高温度与最低温度，包括：
    获取各所述温度采样点的采样信号，并根据所述采样信号获取当前时刻电池包的最高温度与最低温度。
  3. 根据权利要求1或2所述的温度确定方法，其中，所述根据所述最高温度、所述最低温度、所述过温预警阈值以及所述欠温预警阈值，确定当前时刻的电池包温度，包括：
    若所述最高温度大于所述过温预警阈值，或所述最高温度与所述最低温度之间的差值大于第一差值，则确定所述最高温度为当前时刻的电池包温度。
  4. 根据权利要求1或2所述的温度确定方法，其中，所述根据所述最高温度、所述最低温度、所述过温预警阈值以及所述欠温预警阈值，确定当前时刻的电池包温度，包括：
    若所述最高温度小于或等于所述过温预警阈值，且所述最高温度与所述最低温度之间的差值小于或等于所述第一差值，以及所述最低温度小于所述欠温预警阈值，则确定所述最低温度为当前时刻的电池包温度。
  5. 根据权利要求1或2所述的温度确定方法，其中，所述根据所述最高温度、所述最低温度、所述过温预警阈值以及所述欠温预警阈值，确定当前时刻的电池包温度，包括：
    若所述最高温度小于或等于所述过温预警阈值，且所述最高温度与所述最低温度之间的差值小于或等于所述第一差值，以及所述最低温度大于或等于所述欠温预警阈值，则确定当前时刻的电池包温度为：
    所述电池包温度＝((所述过温预警阈值－所述最高温度)÷(所述过温预警阈值－(所述欠温预警阈值+(所述最高温度－所述最低温度))))×所述最低温度+((所述最低温度－所述欠温预警阈值)÷(所述过温预警阈值－(所述欠温预警阈值+(所述最高温度－所述最低温度))))×所述最高温度。
  6. 一种电流阈值确定方法，包括：
    获取电池包中各电芯的电压或SOC值，其中，所述电池包包括至少一个电芯，所述SOC值为电芯剩余容量与电芯标称容量的比值；
    根据各电芯的电压或SOC值，以及当前时刻的电池包温度，确定当前时刻所述电池包充电或放电时的电流阈值；
    其中，当前时刻的电池包温度由所述电池包的最高温度、所述电池包的最低温度、 过温预警阈值以及欠温预警阈值确定。
  7. 根据权利要求6所述的电流阈值确定方法，其中，所述根据各电芯的电压或SOC值，以及当前时刻的电池包温度，确定当前时刻所述电池包充电或放电时的电流阈值，包括：
    若各电芯的电压均相同，则获取任一电芯的电压作为第一电压，并根据所述第一电压与当前时刻的电池包温度，确定所述电流阈值；
    或，若各电芯的SOC值均相同，则获取任一电芯的SOC值作为第一SOC值，并根据所述第一SOC值与当前时刻的电池包温度，确定所述电流阈值。
  8. 根据权利要求6所述的电流阈值确定方法，其中，所述根据各电芯的电压或SOC值，以及当前时刻的电池包温度，确定当前时刻所述电池包充电或放电时的电流阈值，包括：
    若各电芯的电压中存在至少两个大小不同的电压，则获取各电芯的电压中的最大电压与最小电压；
    根据所述最大电压、所述最小电压以及当前时刻的电池包温度，确定所述电流阈值；
    或，若各电芯的SOC值中存在至少两个大小不同的SOC值，则获取各电芯的SOC值中的最大SOC值与最小SOC值；
    根据所述最大SOC值、所述最小SOC值以及当前时刻的电池包温度，确定所述电流阈值。
  9. 根据权利要求8所述的电流阈值确定方法，其中，所述根据所述最大电压、所述最小电压以及当前时刻的电池包温度，确定所述电流阈值，或，根据所述最大SOC值、所述最小SOC值以及当前时刻的电池包温度，确定所述电流阈值，包括：
    根据所述最大电压与当前时刻的电池包温度，获取第一电流阈值；
    根据所述最小电压与当前时刻的电池包温度，获取第二电流阈值；
    将所述第一电流阈值与所述第二电流阈值中的最小值作为所述电流阈值；
    或，根据所述最大SOC值与当前时刻的电池包温度，获取第三电流阈值；
    根据所述最小SOC值与当前时刻的电池包温度，获取第四电流阈值；
    将所述第三电流阈值与所述第四电流阈值中的最小值作为所述电流阈值。
  10. 根据权利要求6-9任意一项所述的电流阈值确定方法，其中，所述电流阈值确定方法还包括：
    将所述电流阈值发送至充电设备或用电设备，以使所述充电设备控制其充电电流小于所述电流阈值，或使所述用电设备控制其用电电流小于所述电流阈值；
    其中，所述电池包用于被所述充电设备充电，以及用于为所述用电设备供电。
  11. 一种温度确定装置，包括：
    温度获取模块，用于获取当前时刻电池包的最高温度与最低温度；
    预警阈值获取模块，用于获取过温预警阈值与欠温预警阈值；
    温度确定模块，用于根据所述最高温度、所述最低温度、所述过温预警阈值以及所述欠温预警阈值，确定当前时刻的电池包温度。
  12. 一种电流阈值确定装置，包括：
    电量状态获取模块，用于获取电池包中各电芯的电压或SOC值，其中，所述电池包 包括至少一个电芯，所述SOC值为电芯剩余电量与电芯标称容量的比值；
    电流阈值确定模块，用于根据各电芯的电压或SOC值，以及当前时刻的电池包温度，确定当前时刻所述电池包充电或放电时的电流阈值；
    其中，当前时刻的电池包温度由所述电池包的最高温度、所述电池包的最低温度、过温预警阈值以及欠温预警阈值确定。
  13. 一种温度确定装置，包括：
    存储器；以及耦接至所述存储器的处理器，所述处理器被配置为基于存储在所述存储器中的指令，执行如权利要求1至5中任一项所述的方法。
  14. 一种电流阈值确定装置，包括：
    存储器；以及耦接至所述存储器的处理器，所述处理器被配置为基于存储在所述存储器中的指令，执行如权利要求6至10中任一项所述的方法。
  15. 一种电池管理系统，包括：如权利要求11或13所述的温度确定装置，和/或，如权利要求12或14所述的电流阈值确定装置。
  16. 一种电池包，包括：电芯模组以及如权利要求15所述的电池管理系统，所述电池管理系统与所述电芯模组电连接，其中，所述电芯模组包括至少一个电芯。
  17. 一种用电设备，包括：负载以及如权利要求16所述的电池包，所述电池包用于为所述负载供电。
  18. 一种计算机可读存储介质，包括：存储有计算机可执行指令，所述计算机可执行指令设置为如权利要求1至10中任一项所述的方法流程。
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