Remaining charging time determination method and device and vehicle

Abstract

The invention discloses a remaining charging time determination method and device and a vehicle, and belongs to the technical field of vehicles. Comprising the steps that first voltage and second voltage are determined based on the battery type, the current electric quantity and the target electric quantity of a power battery of a target vehicle, the target electric quantity is the cut-off electric quantity of charging, the first voltage refers to the total voltage of the power battery when charging starts, and the second voltage refers to the total voltage of the power battery when charging ends; based on the first voltage, the second voltage and target power, the average current in the process from charging starting to charging ending is determined, and the target power is the output power of a charging pile for charging the target vehicle; and determining the residual charging time of the power battery based on the average current, the current electric quantity, the target electric quantity and the total capacity of the power battery. According to the method, the residual charging time is calculated according to the average current in the whole charging process, and compared with the maximum output current, the relatively accurate residual charging time can be determined, so that the user experience is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a method, device and vehicle for determining remaining charging time. Background Art

[0002] With the popularity of new energy, electric vehicles are chosen by most users. Charging is very important for electric vehicles. Generally, when charging a vehicle, the vehicle can calculate the charging time according to user needs.

[0003] In the related art, when calculating the remaining charging time, the maximum output current or the current output current of the charging pile is obtained, and then the remaining charging time is calculated based on the amount of electricity to be charged and the maximum output current or the current output current.

[0004] However, during the charging process, the charging pile outputs a constant power, and as the battery capacity increases, the voltage of the power battery will also increase, and the current entering the power battery will gradually decrease. Therefore, the above method of calculating the remaining charging time will lead to a large deviation in the calculation of the charging time. Summary of the invention

[0005] The present application provides a method, device, vehicle and storage medium for determining the remaining charging time, which can determine the average current during the charging process when charging the power battery, so that the remaining charging time can be calculated based on the average current. In this way, the average current can better represent the current during the entire charging process compared to the maximum output current, so that a relatively accurate remaining charging time can be determined based on the average current. The technical solution includes the following contents.

[0006] In a first aspect, a method for determining a remaining charging time is provided, the method comprising:

[0007] Determine a first voltage and a second voltage based on the battery type, current power and target power of the power battery of the target vehicle, wherein the target power is the cut-off power for charging, the first voltage refers to the total voltage of the power battery when charging starts, and the second voltage refers to the total voltage of the power battery when charging ends;

[0008] Determine an average current from the start of charging to the end of charging based on the first voltage, the second voltage and the target power, wherein the target power is the output power of the charging pile for charging the target vehicle;

[0009] The remaining charging time of the power battery is determined based on the average current, the current power level, the target power level, and the total capacity of the power battery.

[0010] In the present application, the first voltage and the second voltage are first determined based on the battery type, current power and target power of the power battery, that is, the total voltage of the power battery at the start of charging and the total voltage of the power battery at the end of charging are first determined. Then, the average current from the start of charging to the end of charging is determined based on the first voltage, the second voltage and the output power of the charging pile, which is equivalent to estimating the average current during the entire charging process. Finally, the remaining charging time is determined based on the average current, the current power, the target power and the total capacity of the power battery. Due to the characteristic that the current flowing into the power battery during the charging process will gradually decrease, then relative to the maximum output current, the average current is more representative of the current during the entire charging process. This application calculates the remaining charging time based on the estimated average current during the entire charging process, so that a more accurate remaining charging time can be determined, thereby improving the user experience.

[0011] Optionally, determining the first voltage and the second voltage based on the battery type, current power, and target power of the power battery of the target vehicle includes:

[0012] Determine a first cell voltage and a second cell voltage based on the battery type, current power and target power of the power battery of the target vehicle, wherein the first cell voltage is the cell voltage when charging starts, and the second cell voltage is the cell voltage when charging ends;

[0013] Multiplying the first single cell voltage by the number of strings of the power batteries to obtain the first voltage, where the number of strings is the number of single cells of the power batteries;

[0014] The second single cell voltage is multiplied by the number of power battery strings to obtain the second voltage.

[0015] Optionally, determining the first cell voltage and the second cell voltage based on the battery type, current power, and target power of the power battery of the target vehicle includes:

[0016] In the case where the battery type of the power battery is a ternary battery, the single cell voltage intervals corresponding to the current power and the target power are respectively obtained from a target corresponding relationship, wherein the target corresponding relationship is obtained from a relationship between power and voltage in a historical charging process;

[0017] The upper limit voltage of the cell voltage interval corresponding to the current power is determined as the first cell voltage; and the upper limit voltage of the cell voltage interval corresponding to the target power is determined as the second cell voltage.

[0018] Optionally, determining the first cell voltage and the second cell voltage based on the battery type, current power, and target power of the power battery of the target vehicle includes:

[0019] In the case where the battery type of the power battery is a lithium iron phosphate battery, if the current power is greater than or equal to a preset power threshold, the open circuit voltage corresponding to the current power is determined as the first single cell voltage; if the current power is less than the preset power threshold, the current power is added to the preset power to obtain the first power; and the open circuit voltage corresponding to the first power is determined as the first single cell voltage;

[0020] If the target power is greater than or equal to the preset power threshold, the open circuit voltage corresponding to the target power is determined as the second single cell voltage; if the target power is less than the preset power threshold, the target power is added to the preset power to obtain the second power, and the open circuit voltage corresponding to the second power is determined as the second single cell voltage; if the target power is the maximum power of the power battery, the maximum open circuit voltage of the power battery is determined as the second single cell voltage.

[0021] Optionally, the step of determining the target power includes:

[0022] In the case where the charging pile is a DC charging pile, obtaining a current output voltage and a current output current of the charging pile; multiplying the current output voltage and the current output current to obtain the target power;

[0023] In the case where the charging pile is an AC charging pile, the current output voltage, current output current and power factor of the charging pile are obtained, and the current output voltage, current output current and power factor of the charging pile are multiplied to obtain the target power.

[0024] Optionally, determining an average current from the start of charging to the end of charging based on the first voltage, the second voltage, and the target power includes:

[0025] Dividing the target power by the first voltage to obtain a first current, where the first current is a charging current when charging starts;

[0026] Dividing the target power by the second voltage to obtain a second current, where the second current is a charging current when charging ends;

[0027] An average value of the first current and the second current is determined as the average current.

[0028] Optionally, determining the remaining charging time of the power battery based on the average current, the current power, the target power, and the total capacity of the power battery includes:

[0029] Determining a charging efficiency of the power battery based on the current power level and the target power level;

[0030] Determine a target capacity based on the current power, the target power and the total capacity, the target capacity being the capacity of the power battery that needs to be replenished during the charging process;

[0031] Based on the target capacity, the charging efficiency and the average current, a remaining charging time of the power battery is determined.

[0032] Optionally, determining the remaining charging time of the power battery based on the target capacity, the charging efficiency and the average current includes:

[0033] Multiplying the average current by the charging efficiency to obtain a target charging current;

[0034] The target capacity is divided by the target charging current to obtain the remaining charging time.

[0035] In a second aspect, a device for determining a remaining charging time is provided, the device comprising:

[0036] A voltage determination module, used to determine a first voltage and a second voltage based on a battery type, a current power level, and a target power level of a power battery of a target vehicle, wherein the target power level is a cut-off power level for charging, the first voltage refers to a total voltage of the power battery when charging starts, and the second voltage refers to a total voltage of the power battery when charging ends;

[0037] a current determination module, configured to determine an average current from the start of charging to the end of charging based on the first voltage, the second voltage, and a target power, wherein the target power is an output power of a charging pile for charging the target vehicle;

[0038] The charging time determination module is used to determine the remaining charging time of the power battery based on the average current, the current power level, the target power level and the total capacity of the power battery.

[0039] Optionally, the voltage determination module is used to:

[0040] Determine a first cell voltage and a second cell voltage based on the battery type, current power and target power of the power battery of the target vehicle, wherein the first cell voltage is the cell voltage when charging starts, and the second cell voltage is the cell voltage when charging ends;

[0041] Multiplying the first single cell voltage by the number of strings of the power batteries to obtain the first voltage, where the number of strings is the number of single cells of the power batteries;

[0042] The second single cell voltage is multiplied by the number of power battery strings to obtain the second voltage.

[0043] Optionally, the voltage determination module is used to:

[0044] In the case where the battery type of the power battery is a ternary battery, the single cell voltage intervals corresponding to the current power and the target power are respectively obtained from a target corresponding relationship, wherein the target corresponding relationship is obtained from a relationship between power and voltage in a historical charging process;

[0045] The upper limit voltage of the cell voltage interval corresponding to the current power is determined as the first cell voltage; and the upper limit voltage of the cell voltage interval corresponding to the target power is determined as the second cell voltage.

[0046] Optionally, the voltage determination module is used to:

[0047] In the case where the battery type of the power battery is a lithium iron phosphate battery, if the current power is greater than or equal to a preset power threshold, the open circuit voltage corresponding to the current power is determined as the first single cell voltage; if the current power is less than the preset power threshold, the current power is added to the preset power to obtain the first power; and the open circuit voltage corresponding to the first power is determined as the first single cell voltage;

[0048] If the target power is greater than or equal to the preset power threshold, the open circuit voltage corresponding to the target power is determined as the second single cell voltage; if the target power is less than the preset power threshold, the target power is added to the preset power to obtain the second power, and the open circuit voltage corresponding to the second power is determined as the second single cell voltage; if the target power is the maximum power of the power battery, the maximum open circuit voltage of the power battery is determined as the second single cell voltage.

[0049] Optionally, the device further comprises:

[0050] A first power determination module, configured to obtain a current output voltage and a current output current of the charging pile when the charging pile is a DC charging pile; and multiply the current output voltage and the current output current to obtain the target power;

[0051] The second power determination module is used to obtain the current output voltage, current output current and power factor of the charging pile when the charging pile is an AC charging pile, and multiply the current output voltage, current output current and power factor of the charging pile to obtain the target power.

[0052] Optionally, the current determination module is used to:

[0053] Dividing the target power by the first voltage to obtain a first current, where the first current is a charging current when charging starts;

[0054] Dividing the target power by the second voltage to obtain a second current, where the second current is a charging current when charging ends;

[0055] An average value of the first current and the second current is determined as the average current.

[0056] Optionally, the charging time determination module is used to:

[0057] Determining a charging efficiency of the power battery based on the current power level and the target power level;

[0058] Determine a target capacity based on the current power, the target power and the total capacity, the target capacity being the capacity of the power battery that needs to be replenished during the charging process;

[0059] Based on the target capacity, the charging efficiency and the average current, a remaining charging time of the power battery is determined.

[0060] Optionally, the charging time determination module is used to:

[0061] Multiplying the average current by the charging efficiency to obtain a target charging current;

[0062] The target capacity is divided by the target charging current to obtain the remaining charging time.

[0063] In a third aspect, a vehicle is provided, the vehicle comprising:

[0064] A memory for storing executable program codes;

[0065] A processor is used to call and run the executable program code from the memory so that the vehicle executes the above-mentioned remaining charging time determination method.

[0066] In a fourth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the above-mentioned method for determining the remaining charging time is implemented.

[0067] In a fifth aspect, a computer program product comprising instructions is provided, which, when executed on a computer, enables the computer to execute the steps of the above-mentioned method for determining the remaining charging time.

[0068] It can be understood that the beneficial effects of the second, third, fourth and fifth aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0070] Figure 1 It is a scenario schematic diagram of a method for determining remaining charging time provided in an embodiment of the present application;

[0071] Figure 2 is a flow chart of a method for determining remaining charging time provided by an embodiment of the present application;

[0072] Figure 3 It is a structural schematic diagram of a device for determining remaining charging time provided in an embodiment of the present application;

[0073] Figure 4 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0074] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0075] It should be understood that the "multiple" mentioned in this application refers to two or more. In the description of this application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in order to facilitate the clear description of the technical solution of this application, the words "first" and "second" are used to distinguish between the same items or similar items with basically the same functions and effects. Those skilled in the art can understand that the words "first" and "second" do not limit the quantity and execution order, and the words "first" and "second" do not limit them to be different.

[0076] Before describing the method for determining the remaining charging time provided in the embodiment of the present application, the application scenario of the embodiment of the present application is first described.

[0077] For example, Figure 1 is a scenario diagram of a method for determining the remaining charging time provided by an embodiment of the present application. Figure 1 , Figure 1 The vehicle 101 and the charging station 102 are included.

[0078] The vehicle 101 may include a BMS (Battery Management System) system, which is used to manage the charging and discharging of the power battery of the vehicle 101, and can obtain data such as the power battery's charge, temperature, and voltage.

[0079] The charging pile 102 is used to charge the vehicle 101. In the embodiment of the present application, the charging pile 102 can provide a constant output power to charge the power battery of the vehicle 101. The charging pile 102 includes a charging gun, through which the vehicle 101 can be connected to the charging pile 102, so that electric energy can be transmitted from the charging pile 102 to the power battery of the vehicle 101.

[0080] like Figure 1 As shown, after the vehicle 101 is connected to the charging pile 102 through the charging gun, the charging pile 102 can charge the vehicle 101. In an embodiment of the present application, the charging pile 102 can charge the power battery at a constant output power, and the voltage of the power battery shows a gradual increase trend during the charging process, and the current of the power battery shows a gradual decrease trend during the charging process. In this case, the state of the power battery of the vehicle 101 during the charging process changes as follows: at the beginning of charging, since the power battery has a low power level, its voltage is also low, and the current flowing into the power battery at this time is relatively large. Subsequently, as the power of the power battery gradually increases, its voltage will also gradually increase. In order to ensure the safety of the power battery, the current flowing into the power battery at this time will gradually decrease.

[0081] Generally, in order to let the user know the time required for this charging, the time required for this charging will be calculated when the charging pile 102 starts charging the vehicle 101, that is, the remaining charging time when the power battery of the vehicle 101 is charged from the current power to the cut-off power.

[0082] In the related art, when the charging pile 102 is connected to the vehicle 101, the charging pile will output a corresponding current to charge the vehicle 101. When calculating the remaining charging time, the maximum output current of the charging pile 102 or the current output at the current moment can be obtained, and then the remaining charging time is calculated based on the amount of electricity to be charged and the maximum output current or the current output at the current moment.

[0083] However, in the actual charging process, as the battery capacity increases, the voltage of the power battery will also increase, and the current entering the power battery will gradually decrease. Therefore, the method of calculating the remaining charging time based on the current output at the current moment or the maximum output current at the beginning is bound to be inaccurate. Therefore, the above method of calculating the remaining charging time will cause a large deviation in the charging time calculation, thereby reducing the user experience.

[0084] To this end, an embodiment of the present application provides a method for determining the remaining charging time, which can be applied to the scenario of determining the remaining charging time when the charging pile charges the power battery of the vehicle. Specifically, it can also be applied to the scenario of determining the remaining charging time when the charging pile performs slow charging on the power battery of the vehicle.

[0085] Specifically, the current power and target power of this charge are obtained, and then the total voltage of the power battery at the start of charging and the total voltage of the power battery at the end of charging are determined based on the battery type, current power and target power of the power battery. Then the output power of the charging pile is obtained, and based on the total voltage of the power battery at the start of charging, the total voltage of the power battery at the end of charging and the output power of the charging pile, the average current from the start of charging to the end of charging is determined. Finally, based on the average current, the current power, the target power and the total capacity of the power battery, the remaining charging time of the power battery is determined.

[0086] Due to the characteristic that the current flowing into the power battery will gradually decrease during the charging process, the average current is more representative of the current in the entire charging process than the maximum output current. This application calculates the remaining charging time based on the average current in the entire charging process, thereby determining a more accurate remaining charging time, thereby improving the user experience.

[0087] The remaining charging time determination method provided in the embodiment of the present application is explained in detail below.

[0088] Figure 2 : is a flow chart of a method for determining the remaining charging time provided by an embodiment of the present application. The method can be applied to a battery management system (BMS) or a vehicle control unit (VCU) of a vehicle. Figure 2 The method includes the following steps 201-203.

[0089] Step 201: Based on the battery type, current power and target power of the power battery of the target vehicle, determine a first voltage and a second voltage, where the first voltage refers to the total voltage of the power battery when charging starts, and the second voltage refers to the total voltage of the power battery when charging ends.

[0090] At present, there are many kinds of power batteries, and the relationship between the power and voltage of different types of power batteries is different. Therefore, the calculation methods of the first voltage and the second voltage of different types of power batteries are different. In the embodiment of the present application, the battery type of the power battery may include a ternary battery and a lithium iron phosphate battery.

[0091] The current power refers to the remaining power of the power battery.

[0092] The target power is the cut-off power for charging. In some embodiments, the target power can be set by the user. For example, in a certain charging, the user sets the current power to be charged to 80%, then the target power is 80%. In other embodiments, the target power can be a fully charged state, that is, the maximum power of the power battery, such as 100%.

[0093] Since the voltage changes with the power battery's charge during the charging process, the power battery will have a certain voltage when charging starts and a certain voltage when charging ends. Therefore, the first voltage and the second voltage can be determined based on the battery type, current charge, and target charge of the power battery.

[0094] Optionally, the operation of step 201 may be: determining a first single cell voltage and a second single cell voltage based on the battery type, current power and target power of the power battery of the target vehicle; multiplying the first single cell voltage by the number of power battery strings to obtain a first voltage; multiplying the second single cell voltage by the number of power battery strings to obtain a second voltage.

[0095] The first cell voltage is the cell voltage at the start of charging, and is the cell voltage of each cell at the start of charging. The second cell voltage is the cell voltage at the end of charging, and is the cell voltage of each cell at the end of charging.

[0096] The number of power battery strings is the number of power battery cells.

[0097] It should be noted that the power battery is composed of multiple cells, and when the power battery is composed of multiple cells connected in series, the total voltage of the power battery is the sum of the cell voltages of the multiple cells. Consider a situation where the BMS can balance the cell voltages of each cell during the charging process and ensure that the voltages of each cell are consistent. The total voltage of the power battery is the cell voltage multiplied by the number of cells, that is, the cell voltage multiplied by the number of strings.

[0098] The operation of determining the first cell voltage and the second cell voltage based on the battery type, current power level and target power level of the power battery of the target vehicle includes the following two possible implementation methods.

[0099] The first possible implementation method is that when the battery type of the power battery is a ternary battery, the single cell voltage ranges corresponding to the current power and the target power are respectively obtained from the target correspondence relationship; the upper limit voltage of the single cell voltage range corresponding to the current power is determined as the first single cell voltage; and the upper limit voltage of the single cell voltage range corresponding to the target power is determined as the second single cell voltage.

[0100] The target correspondence is the correspondence between different electric charges and the voltage ranges of the power battery cells. The target correspondence includes multiple electric charges and multiple single cell voltage ranges, wherein each of the multiple electric charges has a corresponding single cell voltage range, that is, the voltage that the power battery cell can reach at this electric charge.

[0101] In the embodiment of the present application, the target correspondence relationship is obtained from the relationship between the power and the voltage in the historical charging process. As an example, the target correspondence relationship can be obtained by calibration by a technician based on the relationship between the power and the cell voltage in the historical charging process. For example, in the historical charging process, the cell voltage of the power battery corresponding to different power levels in each charging process is recorded, and then the cell voltage of the power battery corresponding to different power levels in each charging process is integrated to determine the upper and lower limit voltages of the cells of the power battery corresponding to different power levels, that is, the cell voltage range of the power battery corresponding to different power levels, thereby obtaining the target correspondence relationship.

[0102] In addition, due to the polarization phenomenon during charging, the voltage suddenly changes upward, so the static voltage at the start of charging cannot be used. Therefore, the upper limit voltage of the single cell voltage interval corresponding to the current power is determined as the first single cell voltage. In addition, due to the polarization phenomenon at the end of charging, the voltage of the power battery will also reach the upper limit voltage at the end of charging. Therefore, the upper limit voltage of the single cell voltage interval corresponding to the target power is also determined as the second single cell voltage.

[0103] In this case, by calibrating the target correspondence, the relationship between different charges and single-cell voltages during the charging process can be accurately known, and thus the relationship between the current charge and the single-cell voltage and the relationship between the target charge and the single-cell voltage can be known through the target correspondence. In this way, the first single-cell voltage and the second single-cell voltage can be accurately determined based on the target correspondence.

[0104] For example, the following Table 1 is an example of a target correspondence relationship. Referring to Table 1, Table 1 includes multiple power intervals and multiple cell voltage intervals, wherein multiple power intervals correspond to multiple cell voltage intervals one by one, that is, all power included in one power interval corresponds to the same cell voltage interval. For example, if the current power is 35% and the target power is 60%, then it can be determined from the following Table 1 that the cell voltage interval corresponding to the current power is V max ≤3.7, the target power corresponding to the single cell voltage range is V max ≤3.9. It can be further known that the first cell voltage is 3.7 and the second cell voltage is 3.9.

[0105] Table 1

[0106] Power Single cell voltage range 20%<SOC≤30% <![CDATA[V max ≤3.6]]> 30%<SOC≤40% <![CDATA[V max ≤3.7 <!-- 7 -->]]> 50%<SOC≤60% <![CDATA[V max ≤3.9]]> …… ……

[0107] It should be understood that the above-mentioned SOC (State Of Charge) represents the power level of the power battery.

[0108] The embodiment of the present application only uses the above Table 1 as an example to exemplify the above target correspondence relationship, and does not constitute a limitation to the embodiment of the present application.

[0109] In a second possible implementation method, the method for determining the first single cell voltage includes: when the battery type of the power battery is a lithium iron phosphate battery, if the current power is greater than or equal to a preset power threshold, the open circuit voltage corresponding to the current power is determined as the first single cell voltage; if the current power is less than the preset power threshold, the current power is added to the preset power to obtain the first power; and the open circuit voltage corresponding to the first power is determined as the first single cell voltage.

[0110] The preset power threshold can be set in advance, and the preset power threshold can be set relatively large. As an implementation mode, the preset power threshold can be set to be close to a fully charged state, for example, the preset power threshold can be set to 95%.

[0111] The preset power level can be set in advance, and the preset power level can be set according to actual needs, for example, the preset power level can be set to 5%.

[0112] Since lithium iron phosphate has high structural stability, its lattice structure changes little during the lithium ion insertion and extraction process, resulting in a gentle voltage change. Therefore, the voltage of lithium iron phosphate batteries remains relatively stable within a wide SOC range. The open circuit voltage can accurately estimate the battery power, so the open circuit voltage method is used to calculate the single cell voltage of lithium iron phosphate batteries.

[0113] In the embodiment of the present application, the OCV (Open Circuit Voltage)-SOC curve can represent the corresponding relationship between different power levels of the power battery and the open circuit voltage, that is, the open circuit voltage corresponding to different power levels can be obtained from the OCV-SOC curve. In the OCV-SOC curve, the open circuit voltage of the power battery changes little within a certain power range, but when the power level is large, the open circuit voltage changes rapidly, that is, the voltage rises sharply.

[0114] In the above method, when the current power is greater than or equal to the preset power threshold, it means that the current power is large. When the power is large, the open circuit voltage will rise sharply. At this time, if the preset power is added to the current power, the determined open circuit voltage will be very large, which deviates greatly from the actual voltage. Therefore, at this time, the open circuit voltage corresponding to the current power can be directly determined as the first single cell voltage.

[0115] When the current power is less than the preset power threshold, it means that the current power is not large, and the open circuit voltage rises slightly. In addition, due to the polarization phenomenon during the charging process, the voltage will suddenly change upward, and since the open circuit voltage changes slightly when the power is within a certain range, the preset power can be added to the current power to obtain the first power, and the open circuit voltage corresponding to the first power is determined as the first single cell voltage.

[0116] The method for determining the second single-cell voltage includes: if the target power is greater than or equal to a preset power threshold, determining the open circuit voltage corresponding to the target power as the second single-cell voltage; if the target power is less than the preset power threshold, adding the preset power to the target power to obtain the second power, and determining the open circuit voltage corresponding to the second power as the second single-cell voltage; if the target power is the maximum power of the power battery, determining the maximum open circuit voltage of the power battery as the second single-cell voltage.

[0117] In the above method, when the target power is greater than or equal to the preset power threshold, it means that the cut-off power is large. When the power is large, the open circuit voltage will rise sharply. At this time, if the preset power is added to the target power, the determined open circuit voltage will be very large. When charging is ended, the voltage will inevitably not reach the open circuit voltage corresponding to the power after adding the preset power. This is a large deviation from the actual voltage. Therefore, at this time, the open circuit voltage corresponding to the target power can be directly determined as the second single cell voltage.

[0118] When the target power is less than the preset power threshold, it means that the target power is not large, and the open circuit voltage rises slightly. In addition, due to the polarization phenomenon during the charging process, the voltage will suddenly change upward, and when the power of the power battery is within a certain range, the open circuit voltage changes slightly, so the voltage at the end of charging may reach the open circuit voltage corresponding to the second power. Therefore, the preset power can be added to the target power to obtain the second power, and the open circuit voltage corresponding to the second power is determined as the second single cell voltage.

[0119] When the target power is the maximum power of the power battery, it means that the purpose of charging at this time is to make the power battery reach a fully charged state, and the open circuit voltage of the power battery in the fully charged state will also reach a maximum. Therefore, in this case, the maximum open circuit voltage can be directly determined as the second single cell voltage.

[0120] In this case, due to the characteristics of the lithium iron phosphate battery, the corresponding open circuit voltage can be accurately obtained based on the current power and the target power through the OCV-SOC curve, so that a relatively accurate first cell voltage and a second cell voltage can be determined.

[0121] It is worth noting that in some embodiments, the second cell voltage can be calculated first by the above two methods, so that the second voltage of the power battery can be further calculated based on the second cell voltage. In other embodiments, the second voltage can also be determined based on the historical charging data of the power battery.

[0122] The historical charging data of the power battery refers to the data recorded during the historical charging process of the power battery. In the embodiment of the present application, the historical charging data may include the initial power of each charge, the cut-off power, and the total voltage of the power battery at the end of charging (referring to the total voltage corresponding to the power battery when the power is charged to the cut-off power).

[0123] In this case, the operation of determining the second voltage may also be: based on the target power, obtaining charging data corresponding to the reference power from historical charging data; and determining the total voltage at the end of charging in the charging data corresponding to the reference power as the second voltage.

[0124] The reference power is the power at which the cut-off power charged in the historical charging process is the same as the target power. In some embodiments, the reference power can also be the power at which the difference between the cut-off power charged and the target power is less than the target power threshold. Since within a certain power range, the power may correspond to the same voltage interval, the reference power can also be the power at which the cut-off power is close to the target power. In this case, the target power threshold can be set smaller, for example, the target power threshold can be set to 10%.

[0125] Without considering the aging degree of the power battery, each time the power battery is charged, the relationship between the power and the voltage is stable, that is, the voltage of the power battery is stable at a certain power. Therefore, in the embodiment of the present application, historical charging data can also be referred to to obtain the total voltage at the end of charging corresponding to a reference power close to the target power, so as to determine a more accurate second voltage.

[0126] It is worth noting that the total voltage of the power battery at the start of charging and the total voltage of the power battery at the end of charging can be determined through the above step 201. Then, after determining the total voltage of the power battery at the start of charging and the total voltage of the power battery at the end of charging, the average current in the entire charging process can also be determined, so as to determine the remaining charging time based on the average current, that is, continue to execute the following steps 202 and 203.

[0127] Step 202: Based on the first voltage, the second voltage and the target power, determine the average current from the start of charging to the end of charging, where the target power is the output power of the charging pile that charges the target vehicle.

[0128] In the embodiment of the present application, under the condition of constant target power, as the amount of electricity increases, the voltage will increase and the current will decrease. Therefore, the average current from the start of charging to the end of charging can be determined by the total voltage of the power battery at the start of charging and the total voltage of the power battery at the end of charging.

[0129] In this case, by determining the average current from the start of charging to the end of charging based on the first voltage, the second voltage and the target power, the remaining charging time can be subsequently determined based on the average current, thereby determining a more accurate remaining charging time.

[0130] Optionally, the operation of step 202 may be: dividing the target power by the first voltage to obtain a first current; dividing the target power by the second voltage to obtain a second current; and determining an average value of the first current and the second current as the average current.

[0131] The first current is a charging current when charging starts, and the second current is an estimated charging current when charging ends.

[0132] Ideally, when the current decreases linearly during charging, the average value of the first current and the second current is determined as the average current, and a more accurate average current can be obtained. In non-ideal situations, the average value of the first current and the second current is determined as the average current. Compared with determining the remaining charging time by the maximum output current or the current output current in the prior art, a more accurate remaining charging time can be determined by the average current.

[0133] The above specific method of determining the average current is to determine the average current through the following formula (1).

[0134]

[0135] Where I is the average current, P is the target power, V init is the total voltage of the power battery when charging starts, V end It is the total voltage of the power battery when charging is completed. is the first current, is the second current.

[0136] It is worth noting that in the embodiment of the present application, before executing the above step 202, the target power may be determined first.

[0137] Optionally, the target power may be determined in different implementations according to different charging methods of the charging pile.

[0138] When the charging pile is a DC charging pile, the current output voltage and the current output current of the charging pile are obtained; the current output voltage and the current output current are multiplied to obtain the target power.

[0139] When the charging gun is inserted into the target vehicle, the charging pile will output a certain voltage and current to charge the target vehicle. In the embodiment of the present application, the charging pile is charged at a constant power output, so the current output voltage and current output current of the charging pile can be obtained, and the target power is subsequently determined based on the current output voltage and current output current.

[0140] When the charging pile outputs constant power, that is, the output power of the charging pile remains unchanged during the entire charging process, a more accurate target power can be determined by the current output voltage and the current output current.

[0141] When the charging pile is an AC charging pile, the current output voltage, current output current and power factor of the charging pile are obtained, and the current output voltage, current output current and power factor of the charging pile are multiplied to obtain the target power.

[0142] The power factor of a charging pile is used to indicate the charging efficiency of the charging pile to charge the target vehicle. It should be understood that the greater the power factor of the charging pile, the greater its charging efficiency, and the smaller the power factor of the charging pile, the smaller its charging efficiency. Generally, the power factor of a charging pile is between 0.8-1.

[0143] When an AC charging pile charges a target vehicle, the AC power of the power grid is output to the target vehicle, and then the on-board charger (OBC) inside the target vehicle converts the AC power into DC power, which is then used to charge the power battery. However, energy is consumed in this process, so when the charging pile is an AC charging pile, the power factor of the charging pile can also be obtained.

[0144] In this way, a more accurate target power can be determined based on the current output voltage, current output current and power factor of the charging pile.

[0145] Ideally, the operation of determining the target power can also be implemented in the following two situations.

[0146] When the charging pile is a DC charging pile, the maximum output voltage and the maximum output current of the charging pile are obtained; the maximum output voltage and the maximum output current are multiplied to obtain the target power.

[0147] Ideally, the charging pile may output the maximum voltage and maximum current, so the target power is the maximum output power of the charging pile. Therefore, ideally, the maximum output voltage and maximum output current of the charging pile can be obtained, and the target power is determined based on the maximum output voltage and maximum output current.

[0148] In this case, by determining the maximum output power based on the maximum output voltage and the maximum output current, when the charging pile subsequently charges the target vehicle at the maximum output power, the power battery can be charged at the fastest speed.

[0149] When the charging pile is an AC charging pile, the maximum output voltage, maximum output current and power factor of the charging pile are obtained, and the maximum output voltage, maximum output current and power factor of the charging pile are multiplied to obtain the target power.

[0150] For the same reason, under ideal circumstances, the charging pile may output the maximum output power. Therefore, by determining the maximum output power based on the maximum output voltage and the maximum output current, when the charging pile subsequently charges the target vehicle at the maximum output power, the power battery can be charged at the fastest speed.

[0151] It is worth noting that the average current from the start of charging to the end of charging can be determined through the above step 202, which is equivalent to estimating the average current in the entire charging process. After estimating the average current from the start of charging to the end of charging through the above step 202, the remaining charging time of the power battery can also be determined based on the average current.

[0152] Step 203: Determine the remaining charging time of the power battery based on the average current, the current power level, the target power level and the total capacity of the power battery.

[0153] Due to the characteristic that the current flowing into the power battery will gradually decrease during the charging process, the average current is more representative of the median current during the entire charging process than the maximum output current.

[0154] In this case, by calculating the remaining charging time based on the estimated average current, current power, target power and total capacity of the power battery during the entire charging process, a more accurate remaining charging time can be determined, thereby improving the user experience.

[0155] Optionally, the operation of step 203 may include the following steps (1) to (3).

[0156] (1) Determine the charging efficiency of the power battery based on the current power and the target power.

[0157] The charging efficiency of a power battery refers to how much of the input electrical energy is effectively stored in the power battery during the charging process. It is calculated by comparing the energy actually stored in the power battery with the total input energy.

[0158] Optionally, the operation of step (1) can be implemented in the following two possible ways.

[0159] The first possible implementation method is to subtract the current power from the target power to obtain the charging power; multiply the charging power by the total power of the power battery to obtain the charging energy; and divide the charging energy by the target power to obtain the charging efficiency of the power battery.

[0160] It is worth noting that before determining the charging efficiency of the power battery, the target power provided by the charging pile to the power battery can also be obtained first.

[0161] The target electric energy refers to the total energy provided by the charging pile to the power battery during this charging process. In the embodiment of the present application, the target electric energy can be obtained from the historical charging data of the charging pile.

[0162] Specifically, the historical charging data of the charging pile may include the initial power and the cut-off power of each charge, and the total power provided by the charging pile to the power battery from the initial power to the cut-off power. In this case, the total power provided for charging the power battery when the initial power is the same as the current power and the cut-off power is the same as the target power can be obtained from the historical charging data of the charging pile, and the obtained total power is determined as the target power.

[0163] In this way, a relatively accurate target electric energy provided to the power battery can be obtained from the historical charging data of the charging pile, so that a relatively accurate charging efficiency of the power battery can be determined later.

[0164] For example, the current power is 20%, the target power is 80%, the total power of the power battery is 5kWh (kilowatt-hours), and the target power of the charging pile obtained is 40kWh.

[0165] The charging efficiency of the power battery is calculated as: Among them, is the charging efficiency of the power battery.

[0166] A second possible implementation method is to subtract the current power from the target power to obtain the charging power; and based on the charging power, obtain the corresponding charging efficiency in a preset corresponding relationship as the charging efficiency of the power battery.

[0167] The preset corresponding relationship is the corresponding relationship between the charging power and the charging efficiency. Optionally, the preset corresponding relationship can be pre-calibrated by a technician.

[0168] The preset corresponding relationship may include multiple charging powers and multiple charging efficiencies, wherein the multiple charging powers correspond to the multiple charging efficiencies one by one, and each of the multiple charging powers has a corresponding charging efficiency.

[0169] For example, the following Table 2 is an example of a preset corresponding relationship, referring to Table 2, which includes multiple charging capacities and multiple charging efficiencies, wherein the multiple charging capacities and the multiple charging efficiencies correspond one to one. For example, in the embodiment of the present application, the charging capacity is 60%, and the corresponding charging efficiency can be obtained from the following Table 2 as 80%.

[0170] Table 2

[0171] Charging capacity Charging efficiency 40％ 65％ 60％ 80％ 80％ 85％ …… ……

[0172] The embodiment of the present application only uses Table 2 as an example to illustrate the above preset corresponding relationship, and does not constitute a limitation to the embodiment of the present application.

[0173] (2) Determine the target capacity based on the current power, target power and total capacity.

[0174] The target capacity is the capacity that needs to be replenished during the charging process of the power battery, and the target capacity corresponds to the charging power to be charged.

[0175] Specifically, the operation of step (2) may be: subtracting the current power from the target power to obtain the charging power; and multiplying the charging power by the total capacity of the power battery to obtain the target capacity.

[0176] In this case, by calculating the target capacity, the total capacity of the power battery to be replenished during this charging process can be known, so that the remaining charging time of the power battery can be calculated based on this later.

[0177] For example, the current power is 20%, the target power is 80%, and the total capacity of the power battery is 5Ah (ampere-hour), then the target capacity is calculated as: 5×(80%-20%)=3Ah.

[0178] (3) Determine the remaining charging time of the power battery based on the target capacity, charging efficiency and average current.

[0179] Based on the target capacity and average current, the remaining charging time of the power battery under ideal conditions can be determined, and then the remaining charging time of the power battery calculated under ideal conditions can be referred to by the charging efficiency, so as to determine the remaining charging time that is suitable for the actual charging situation. Alternatively, the average charging current flowing into the power battery that is suitable for the actual charging situation can be determined based on the average current and charging efficiency, and then the remaining charging time that is suitable for the actual charging situation can be determined in combination with the target capacity.

[0180] In this case, a more accurate remaining charging time of the power battery can be determined by comprehensively considering the target capacity, charging efficiency and average current.

[0181] Specifically, the operation of step (3) may be: multiplying the average current by the charging efficiency to obtain the target charging current; and dividing the target capacity by the target charging current to obtain the remaining charging time.

[0182] The target charging current is the charging current that actually flows into the power battery after taking the charging efficiency into consideration.

[0183] In this case, the specific operation of the above step (3) is to determine the remaining charging time of the power battery through the following formula (2).

[0184]

[0185] Wherein, T is the remaining charging time of the power battery, Q is the target capacity of the power battery, I is the average current, and η is the charging efficiency of the power battery.

[0186] It is worth noting that the remaining charging time determination method provided in the embodiment of the present application can determine the total voltage of the power battery at the start of charging and the total voltage of the power battery at the end of charging according to the initial charging power and the charging cut-off power (the total voltage calculation method of different battery types is different). Then, the average current flowing into the power battery during the entire charging process is estimated in combination with the output power of the charging pile. The average current is closer to the actual charging current during the charging process. Then, the average current is used as the initial current for calculating the remaining charging time, thereby reducing the calculation deviation of the remaining charging time.

[0187] In an embodiment of the present application, the BMS or VCU first determines the first voltage and the second voltage based on the battery type, current power and target power of the power battery, that is, first determines the total voltage of the power battery when charging starts and the total voltage of the power battery when charging ends. Then, the average current from the start of charging to the end of charging is determined based on the first voltage, the second voltage and the output power of the charging pile, which is equivalent to estimating the average current during the entire charging process. Finally, the remaining charging time is determined based on the average current, the current power, the target power and the total capacity of the power battery. Due to the characteristic that the current flowing into the power battery during the charging process will gradually decrease, then relative to the maximum output current, the average current can better represent the current in the entire charging process. The present application calculates the remaining charging time based on the estimated average current during the entire charging process, so that a more accurate remaining charging time can be determined, thereby improving the user experience.

[0188] Figure 3 : is a schematic diagram of a structure of a device for determining the remaining charging time provided in an embodiment of the present application. The device for determining the remaining charging time can be implemented by software, hardware, or a combination of both to form part or all of a vehicle, and the vehicle can be as follows Figure 4 Vehicle shown. See Figure 3 The device includes: a voltage determination module 301, a current determination module 302 and a charging time determination module 303.

[0189] The voltage determination module 301 is used to determine a first voltage and a second voltage based on the battery type, current power and target power of the power battery of the target vehicle, the target power is the cut-off power of charging, the first voltage refers to the total voltage of the power battery when charging starts, and the second voltage refers to the total voltage of the power battery when charging ends;

[0190] A current determination module 302 is used to determine an average current from the start of charging to the end of charging based on the first voltage, the second voltage and the target power, where the target power is the output power of the charging pile charging the target vehicle;

[0191] The charging time determination module 303 is used to determine the remaining charging time of the power battery based on the average current, the current power level, the target power level and the total capacity of the power battery.

[0192] Optionally, the voltage determination module 301 is used to:

[0193] Based on the battery type, current power and target power of the power battery of the target vehicle, determine a first cell voltage and a second cell voltage, the first cell voltage being the cell voltage when charging starts, and the second cell voltage being the cell voltage when charging ends;

[0194] The first single cell voltage is multiplied by the number of power battery strings to obtain a first voltage, where the number of strings is the number of single cells in the power battery;

[0195] The second single cell voltage is multiplied by the number of power battery strings to obtain a second voltage.

[0196] Optionally, the voltage determination module 301 is used to:

[0197] In the case where the battery type of the power battery is a ternary battery, the cell voltage intervals corresponding to the current power and the target power are respectively obtained from the target corresponding relationship, and the target corresponding relationship is obtained from the relationship between the power and the voltage in the historical charging process;

[0198] The upper limit voltage of the cell voltage interval corresponding to the current power is determined as the first cell voltage; the upper limit voltage of the cell voltage interval corresponding to the target power is determined as the second cell voltage.

[0199] Optionally, the voltage determination module 301 is used to:

[0200] In the case where the battery type of the power battery is a lithium iron phosphate battery, if the current power is greater than or equal to the preset power threshold, the open circuit voltage corresponding to the current power is determined as the first single cell voltage; if the current power is less than the preset power threshold, the current power is added to the preset power to obtain the first power; the open circuit voltage corresponding to the first power is determined as the first single cell voltage;

[0201] If the target power is greater than or equal to the preset power threshold, the open circuit voltage corresponding to the target power is determined as the second single cell voltage; if the target power is less than the preset power threshold, the target power is added to the preset power to obtain the second power, and the open circuit voltage corresponding to the second power is determined as the second single cell voltage; if the target power is the maximum power of the power battery, the maximum open circuit voltage of the power battery is determined as the second single cell voltage.

[0202] Optionally, the device further comprises:

[0203] A first power determination module is used to obtain the current output voltage and the current output current of the charging pile when the charging pile is a DC charging pile; and multiply the current output voltage and the current output current to obtain the target power;

[0204] The second power determination module is used to obtain the current output voltage, current output current and power factor of the charging pile when the charging pile is an AC charging pile, and multiply the current output voltage, current output current and power factor of the charging pile to obtain the target power.

[0205] Optionally, the current determination module 302 is used to:

[0206] Dividing the target power by the first voltage to obtain a first current, where the first current is a charging current when charging starts;

[0207] Dividing the target power by the second voltage to obtain a second current, where the second current is the charging current when charging ends;

[0208] An average value of the first current and the second current is determined as an average current.

[0209] Optionally, the charging time determination module 303 is used to:

[0210] Determine the charging efficiency of the power battery based on the current power and the target power;

[0211] Based on the current power, target power and total capacity, the target capacity is determined. The target capacity is the capacity that needs to be replenished during the charging process of the power battery.

[0212] Determine the remaining charging time of the power battery based on the target capacity, charging efficiency and average current.

[0213] Optionally, the charging time determination module 303 is used to:

[0214] Multiply the average current by the charging efficiency to get the target charging current;

[0215] Divide the target capacity by the target charging current to get the remaining charging time.

[0216] In an embodiment of the present application, the first voltage and the second voltage are first determined based on the battery type, current power and target power of the power battery, that is, the total voltage of the power battery at the start of charging and the total voltage of the power battery at the end of charging are first determined. Then, the average current from the start of charging to the end of charging is determined based on the first voltage, the second voltage and the output power of the charging pile, which is equivalent to estimating the average current during the entire charging process. Finally, the remaining charging time is determined based on the average current, the current power, the target power and the total capacity of the power battery. Due to the characteristic that the current flowing into the power battery during the charging process will gradually decrease, then relative to the maximum output current, the average current can better represent the current in the entire charging process. The present application calculates the remaining charging time based on the estimated average current in the entire charging process, so that a more accurate remaining charging time can be determined, thereby improving the user experience.

[0217] It should be noted that: when the remaining charging time determination device provided in the above embodiment calculates the remaining charging time at the beginning of power battery charging, it only uses the division of the above-mentioned functional modules as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0218] The functional units and modules in the above embodiments may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit, and the above integrated units may be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the protection scope of the embodiments of the present application.

[0219] The remaining charging time determination device and the remaining charging time determination method embodiments provided in the above embodiments belong to the same concept. The specific working process of the units and modules in the above embodiments and the technical effects brought about can be found in the method embodiment part and will not be repeated here.

[0220] Figure 4 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application.

[0221] For example, Figure 4As shown, the vehicle 400 includes: a memory 41 and a processor 40, wherein the memory 41 stores an executable program code 42, and the processor 40 is used to call and execute the executable program code 42 to perform the above-mentioned remaining charging time determination method.

[0222] In this embodiment, the functional modules of the vehicle can be divided according to the above method example. For example, each functional module can be corresponded, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware. It should be noted that the division of modules in this embodiment is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0223] In the case of dividing each functional module according to each function, the vehicle may include: a voltage determination module, a current determination module and a charging time determination module. It should be noted that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, which will not be repeated here.

[0224] The vehicle provided in this embodiment is used to execute the above-mentioned method for determining the remaining charging time, and thus can achieve the same effect as the above-mentioned implementation method.

[0225] In the case of an integrated unit, the vehicle may include a processing module and a storage module. The processing module may be used to control and manage the actions of the vehicle. The storage module may be used to support the vehicle in executing corresponding program codes and data.

[0226] The processing module may be a processor or a controller, which may implement or execute various exemplary logic blocks, modules and circuits shown in conjunction with the disclosure of the present application. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc. The storage module may be a memory.

[0227] This embodiment also provides a computer-readable storage medium, in which a computer program code is stored. When the computer program code is executed on a computer, the computer executes the above-mentioned related method steps to implement the above-mentioned method for determining the remaining charging time in the above-mentioned embodiment.

[0228] This embodiment also provides a computer program product. When the computer program product is run on a computer, the computer is caused to execute the above-mentioned related steps to implement the above-mentioned method for determining the remaining charging time in the above-mentioned embodiment.

[0229] Among them, the vehicle, computer-readable storage medium, computer program product or chip provided in this embodiment are all used to execute the method provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the method provided above and will not be repeated here.

[0230] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and brevity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0231] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0232] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for determining remaining charging time, characterized in that: The method comprises: Determine a first voltage and a second voltage based on the battery type, current power and target power of the power battery of the target vehicle, wherein the target power is the cut-off power for charging, the first voltage refers to the total voltage of the power battery when charging starts, and the second voltage refers to the total voltage of the power battery when charging ends; Determine an average current from the start of charging to the end of charging based on the first voltage, the second voltage and the target power, wherein the target power is the output power of the charging pile for charging the target vehicle; The remaining charging time of the power battery is determined based on the average current, the current power level, the target power level, and the total capacity of the power battery.

2. The method according to claim 1, characterized in that The determining of the first voltage and the second voltage based on the battery type, current power, and target power of the power battery of the target vehicle includes: Determine a first cell voltage and a second cell voltage based on the battery type, current power and target power of the power battery of the target vehicle, wherein the first cell voltage is the cell voltage when charging starts, and the second cell voltage is the cell voltage when charging ends; Multiplying the first single cell voltage by the number of strings of the power batteries to obtain the first voltage, where the number of strings is the number of single cells of the power batteries; The second single cell voltage is multiplied by the number of power battery strings to obtain the second voltage.

3. The method according to claim 2, characterized in that The determining of the first cell voltage and the second cell voltage based on the battery type, current power and target power of the power battery of the target vehicle includes: In the case where the battery type of the power battery is a ternary battery, the single cell voltage intervals corresponding to the current power and the target power are respectively obtained from a target corresponding relationship, wherein the target corresponding relationship is obtained from a relationship between power and voltage in a historical charging process; The upper limit voltage of the cell voltage interval corresponding to the current power is determined as the first cell voltage; and the upper limit voltage of the cell voltage interval corresponding to the target power is determined as the second cell voltage.

4. The method according to claim 2, characterized in that The determining of the first cell voltage and the second cell voltage based on the battery type, current power and target power of the power battery of the target vehicle includes: In the case where the battery type of the power battery is a lithium iron phosphate battery, if the current power is greater than or equal to a preset power threshold, the open circuit voltage corresponding to the current power is determined as the first single cell voltage; if the current power is less than the preset power threshold, the current power is added to the preset power to obtain the first power; and the open circuit voltage corresponding to the first power is determined as the first single cell voltage; If the target power is greater than or equal to the preset power threshold, the open circuit voltage corresponding to the target power is determined as the second single cell voltage; if the target power is less than the preset power threshold, the target power is added to the preset power to obtain the second power, and the open circuit voltage corresponding to the second power is determined as the second single cell voltage; if the target power is the maximum power of the power battery, the maximum open circuit voltage of the power battery is determined as the second single cell voltage.

5. The method according to claim 1, characterized in that The step of determining the target power comprises: In the case where the charging pile is a DC charging pile, obtaining a current output voltage and a current output current of the charging pile; multiplying the current output voltage and the current output current to obtain the target power; In the case where the charging pile is an AC charging pile, the current output voltage, current output current and power factor of the charging pile are obtained, and the current output voltage, current output current and power factor of the charging pile are multiplied to obtain the target power.

6. The method according to claim 1, characterized in that The determining, based on the first voltage, the second voltage, and the target power, an average current from the start of charging to the end of charging includes: Dividing the target power by the first voltage to obtain a first current, where the first current is a charging current when charging starts; Dividing the target power by the second voltage to obtain a second current, where the second current is a charging current when charging ends; An average value of the first current and the second current is determined as the average current.

7. The method according to claim 1, characterized in that The determining the remaining charging time of the power battery based on the average current, the current power, the target power, and the total capacity of the power battery includes: Determining a charging efficiency of the power battery based on the current power level and the target power level; Determine a target capacity based on the current power, the target power and the total capacity, the target capacity being the capacity of the power battery that needs to be replenished during the charging process; Based on the target capacity, the charging efficiency and the average current, a remaining charging time of the power battery is determined.

8. The method according to claim 7, characterized in that The determining the remaining charging time of the power battery based on the target capacity, the charging efficiency and the average current includes: Multiplying the average current by the charging efficiency to obtain a target charging current; The target capacity is divided by the target charging current to obtain the remaining charging time.

9. A device for determining remaining charging time, characterized in that: The device comprises: A voltage determination module, used to determine a first voltage and a second voltage based on a battery type, a current power level, and a target power level of a power battery of a target vehicle, wherein the target power level is a cut-off power level for charging, the first voltage refers to a total voltage of the power battery when charging starts, and the second voltage refers to a total voltage of the power battery when charging ends; a current determination module, configured to determine an average current from the start of charging to the end of charging based on the first voltage, the second voltage, and a target power, wherein the target power is an output power of a charging pile for charging the target vehicle; The charging time determination module is used to determine the remaining charging time of the power battery based on the average current, the current power level, the target power level and the total capacity of the power battery.

10. A vehicle, characterized in that: The vehicle comprises: A memory for storing executable program codes; A processor, configured to call and run the executable program code from the memory so that the vehicle executes the method according to any one of claims 1 to 8.

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