Battery coolant temperature control method and related equipment

Abstract

A battery coolant temperature control method and related equipment. The method includes: calculating the temperature difference between the battery pack temperature and the battery pack inlet water temperature based on the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack; determining a first correction coefficient and a second correction coefficient based on the battery pack temperature; adjusting the temperature difference based on the first correction coefficient and the second correction coefficient to obtain a target temperature difference; calculating a target required water temperature based on the target temperature difference and the battery pack temperature, so that the water cooling unit can output a battery coolant with the same target required water temperature. Through the present invention, dynamic adjustment of the target required water temperature is achieved, so that the water cooling unit can output a suitable battery coolant temperature regardless of the working conditions, solving the technical problem that the prior art cannot output a suitable target required water temperature to restore the battery to normal temperature, and also increases the energy consumption and noise of the vehicle.

Description

Technical Field

[0001] The present application relates to the technical field of new energy vehicles, and in particular to a battery coolant temperature control method and related equipment. Background Art

[0002] At present, lithium batteries generate chemical reaction heat and resistance heat during the charging and discharging process, which may cause the battery temperature to be too high, affecting the battery life and safety. At the same time, lithium batteries will reduce discharge power and efficiency at low temperatures. There are also safety issues that cannot be ignored when charging lithium batteries at low temperatures. Therefore, the performance and life of lithium batteries are closely related to their temperature. It is necessary to control the temperature of lithium batteries within a reasonable range.

[0003] In the related technology, when cooling an overheated battery, the fixed target required water temperature corresponding to when the vehicle is in a charging condition or a driving condition is first sent to the thermal management system, and then the water cooling unit outputs a low-temperature coolant close to the target required water temperature. The low-temperature coolant completes heat exchange inside the battery, thereby taking away the heat and cooling the battery.

[0004] However, during the actual driving of the vehicle, the vehicle may be in a variety of different working conditions, and the target required water temperature of the thermal management system is different when the vehicle is in different working conditions. If the vehicle is in other working conditions, and still sends the fixed target required water temperature corresponding to the charging or driving condition to the thermal management system, not only may the battery fail to quickly return to normal temperature, but it may also increase the vehicle's energy consumption and noise, affecting the comfort and economy of the vehicle. Summary of the invention

[0005] The present application provides a battery coolant temperature control method and related equipment, which can solve the technical problems in the prior art that when the vehicle is in different working conditions, the appropriate target required water temperature cannot be output to quickly restore the battery to normal temperature, and the energy consumption and noise of the vehicle are increased.

[0006] In a first aspect, an embodiment of the present application provides a battery coolant temperature control method, the battery coolant temperature control method comprising:

[0007] The temperature difference between the battery pack temperature and the battery pack inlet water temperature is calculated based on the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack, wherein the battery pack temperature is the average temperature of multiple single cells included in the battery pack;

[0008] determining a first correction factor and a second correction factor based on the battery pack temperature;

[0009] Adjusting the temperature difference based on the first correction coefficient and the second correction coefficient to obtain a target temperature difference;

[0010] A target required water temperature is calculated based on the target temperature difference and the battery pack temperature, so that the water cooling unit can output battery coolant with the same target required water temperature.

[0011] In combination with the first aspect, in one embodiment, the step of calculating the temperature difference between the battery pack temperature and the battery pack inlet water temperature based on the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack includes:

[0012] Substitute the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack into the first preset formula to calculate the temperature difference between the battery pack temperature and the battery pack inlet water temperature. The first preset formula is as follows:

[0013]

[0014] Among them, ΔT0 is used to represent the temperature difference between the battery pack temperature and the battery pack water inlet temperature, Q est It is used to indicate the total heat generation power of the battery pack, h is used to indicate the heat transfer coefficient of the battery pack, and S is used to indicate the heat transfer area of ​​the battery pack.

[0015] In combination with the first aspect, in one implementation, the step of determining the first correction coefficient and the second correction coefficient based on the battery pack temperature includes:

[0016] Determining a target temperature interval for the battery pack temperature among a plurality of preset temperature intervals;

[0017] Determine a preset value corresponding to the target temperature range as a first correction coefficient;

[0018] The battery pack temperature change rate is calculated based on the battery pack temperature within a preset time period;

[0019] Determining a target temperature change rate interval in which the battery pack temperature change rate is located among a plurality of preset temperature change rate intervals;

[0020] A preset value corresponding to the target temperature change rate interval is determined as a second correction coefficient.

[0021] In combination with the first aspect, in one implementation, the step of adjusting the temperature difference based on the first correction coefficient and the second correction coefficient to obtain a target temperature difference includes:

[0022] Substitute the first correction coefficient, the second correction coefficient and the temperature difference into the second preset formula to calculate the target temperature difference. The second preset formula is as follows:

[0023]

[0024] Where, ΔTest It is used to represent the target temperature difference, A is used to represent the first correction coefficient, X is used to represent the second correction coefficient, and ΔT0 is used to represent the temperature difference between the battery pack temperature and the battery pack water inlet temperature.

[0025] In combination with the first aspect, in one implementation, the step of calculating the target required water temperature based on the target temperature difference and the battery pack temperature includes:

[0026] The difference between the battery pack temperature and the target temperature difference is calculated, and the difference is used as the target required water temperature.

[0027] In a second aspect, an embodiment of the present application provides a battery coolant temperature control device, the battery coolant temperature control device comprising:

[0028] A first calculation module, configured to calculate a temperature difference between a battery pack temperature and a battery pack water inlet temperature based on a total heat generation power of the battery pack, a heat exchange coefficient of the battery pack, and a heat exchange area of ​​the battery pack, wherein the battery pack temperature is an average value of temperatures of a plurality of single cells included in the battery pack;

[0029] a parameter determination module, configured to determine a first correction coefficient and a second correction coefficient based on the battery pack temperature;

[0030] a parameter adjustment module, configured to adjust the temperature difference based on the first correction coefficient and the second correction coefficient to obtain a target temperature difference;

[0031] The second calculation module is used to calculate a target required water temperature based on the target temperature difference and the battery pack temperature, so that the water cooling unit can output battery coolant with the same target required water temperature.

[0032] In conjunction with the second aspect, in one implementation, the first calculation module is used to:

[0033] Substitute the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack into the first preset formula to calculate the temperature difference between the battery pack temperature and the battery pack inlet water temperature. The first preset formula is as follows:

[0034]

[0035] Among them, ΔT0 is used to represent the temperature difference between the battery pack temperature and the battery pack water inlet temperature, Q est It is used to indicate the total heat generation power of the battery pack, h is used to indicate the heat transfer coefficient of the battery pack, and S is used to indicate the heat transfer area of ​​the battery pack.

[0036] In conjunction with the second aspect, in one implementation, the parameter determination module is used to:

[0037] Determining a target temperature interval for the battery pack temperature among a plurality of preset temperature intervals;

[0038] Determine a preset value corresponding to the target temperature range as a first correction coefficient;

[0039] The battery pack temperature change rate is calculated based on the battery pack temperature within a preset time period;

[0040] Determining a target temperature change rate interval in which the battery pack temperature change rate is located among a plurality of preset temperature change rate intervals;

[0041] A preset value corresponding to the target temperature change rate interval is determined as a second correction coefficient.

[0042] In a third aspect, an embodiment of the present application provides a battery coolant temperature control device, wherein the battery coolant temperature control device comprises a processor, a memory, and a battery coolant temperature control program stored in the memory and executable by the processor, wherein when the battery coolant temperature control program is executed by the processor, the steps of the battery coolant temperature control method as described above are implemented.

[0043] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, on which a battery coolant temperature control program is stored, wherein when the battery coolant temperature control program is executed by a processor, the steps of the battery coolant temperature control method as described above are implemented.

[0044] The beneficial effects brought by the technical solution provided by the embodiment of the present application include at least:

[0045] The temperature difference between the battery pack temperature and the battery pack water inlet temperature is calculated based on the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack, wherein the battery pack temperature is the average temperature of multiple single cells contained in the battery pack; the first correction coefficient and the second correction coefficient are determined based on the battery pack temperature; the temperature difference is adjusted based on the first correction coefficient and the second correction coefficient to obtain the target temperature difference; the target required water temperature is calculated based on the target temperature difference and the battery pack temperature, so that the water cooling unit can output the battery coolant with the same target required water temperature. By dynamically adjusting the temperature difference between the battery pack temperature and the battery pack water inlet temperature, the target required water temperature is dynamically adjusted, so that the water cooling unit can output the appropriate battery coolant temperature regardless of the working condition, which not only ensures that the battery temperature can be restored to a suitable temperature regardless of the working condition, but also reduces energy consumption, and solves the technical problem in the prior art that when the vehicle is in other working conditions other than charging or driving conditions, it is impossible to output the appropriate target required water temperature to restore the battery to normal temperature, and the energy consumption and noise of the vehicle will also increase. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a flow chart of an embodiment of a method for controlling the temperature of a battery coolant of the present application;

[0047] Figure 2 For this application Figure 1 Detailed flow chart of step S20;

[0048] Figure 3 This is a functional module diagram of an embodiment of a battery coolant temperature control device of the present application;

[0049] Figure 4 This is a schematic diagram of the hardware structure of the battery coolant temperature control device involved in the embodiment of the present application. DETAILED DESCRIPTION

[0050] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0051] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0052] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0053] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; the “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, 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 the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0054] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0055] First, some technical terms in the present application are explained to facilitate those skilled in the art to understand the present application.

[0056] Battery pack: It is composed of multiple single cells.

[0057] Battery pack: It is composed of multiple battery groups.

[0058] 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.

[0059] In a first aspect, an embodiment of the present application provides a battery coolant temperature control method.

[0060] In one embodiment, referring to Figure 1 , Figure 1 This is a flow chart of an embodiment of a method for controlling the temperature of a battery coolant in the present application. Figure 1 As shown, the battery coolant temperature control method includes:

[0061] Step S10, calculating the temperature difference between the battery pack temperature and the battery pack inlet water temperature based on the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack, wherein the battery pack temperature is an average value of the temperatures of multiple single cells included in the battery pack;

[0062] In this embodiment, the battery pack includes a plurality of single cells. Based on the heat generation power calculation formula of the single cell, The heat generation power, I is used to represent the single battery current, T BIt is used to indicate the temperature of a single cell, and R is used to indicate the internal resistance of a single cell. It is used to represent the entropy thermal coefficient of a single cell. Based on the heat generation power of each single cell, the total heat generation power Q of the battery pack can be calculated. est ,in, i is used to represent the i-th single cell, and n is used to represent the number of single cells. Then, based on the total heat generation power of the battery pack, the heat transfer coefficient of the battery pack, and the heat transfer area of ​​the battery pack, the temperature difference between the battery pack temperature and the battery pack inlet water temperature can be calculated, where the battery pack temperature is the average temperature of multiple single cells contained in the battery pack.

[0063] Step S20, determining a first correction coefficient and a second correction coefficient based on the battery pack temperature;

[0064] In this embodiment, since the battery pack includes multiple single cells and the temperature of each single cell is different, the average value of the temperatures of the multiple single cells included in the battery pack is used as the temperature of the battery pack, and the first correction coefficient and the second correction coefficient are determined based on the temperature of the battery pack, wherein the first correction coefficient and the second correction coefficient are used to adjust the temperature difference between the battery pack temperature and the water inlet temperature of the battery pack.

[0065] Step S30, adjusting the temperature difference based on the first correction coefficient and the second correction coefficient to obtain a target temperature difference;

[0066] In this embodiment, after obtaining the temperature difference between the battery pack temperature and the battery pack inlet water temperature, the temperature difference between the battery pack temperature and the battery pack inlet water temperature is adjusted based on the first correction coefficient and the second correction coefficient to obtain an adjusted target temperature difference.

[0067] Step S40, calculating a target required water temperature based on the target temperature difference and the battery pack temperature, so that the water cooling unit can output battery coolant with the same target required water temperature.

[0068] In this embodiment, the target required water temperature can be calculated based on the target temperature difference and the battery pack temperature, so that the water cooling unit can output the battery coolant with the same target required water temperature. Specifically, if the target required water temperature is 30°C calculated based on the target temperature difference and the battery pack temperature, the water cooling unit outputs the battery coolant with the same target required water temperature, that is, the battery coolant output by the water cooling unit is also 30°C. The temperature of the battery coolant output by the water cooling unit is changed by dynamically adjusting the temperature difference between the battery pack temperature and the battery pack inlet water temperature. On the one hand, the cooling power of the water cooling unit is made the same as the heat generation power of the battery, which has an energy-saving effect; on the other hand, the water cooling unit outputs a suitable battery coolant temperature, which ensures that the battery temperature can be quickly restored to an appropriate temperature.

[0069] In this embodiment, the temperature difference between the battery pack temperature and the battery pack inlet water temperature is calculated based on the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack, wherein the battery pack temperature is the average value of the temperatures of multiple single cells contained in the battery pack; a first correction coefficient and a second correction coefficient are determined based on the battery pack temperature; the temperature difference is adjusted based on the first correction coefficient and the second correction coefficient to obtain a target temperature difference; and a target required water temperature is calculated based on the target temperature difference and the battery pack temperature, so that the water cooling unit can output battery coolant with the same target required water temperature. Through this embodiment, a first correction coefficient and a second correction coefficient are determined based on the battery pack temperature, and then the temperature difference between the battery pack temperature and the battery pack water inlet temperature is adjusted based on the first correction coefficient and the second correction coefficient to obtain an adjusted target temperature difference, and then the target required water temperature can be calculated based on the adjusted target temperature difference and the battery pack temperature. By dynamically adjusting the temperature difference between the battery pack temperature and the battery pack water inlet temperature, dynamic adjustment of the target required water temperature is achieved, so that the water cooling unit can output a suitable battery coolant temperature under any operating condition, which not only ensures that the battery temperature can be restored to an appropriate temperature under any operating condition, but also reduces energy consumption, and solves the technical problem in the prior art that when the vehicle is in a charging condition or other operating conditions other than a driving condition, it is impossible to output a suitable target required water temperature to restore the battery to a normal temperature, and the energy consumption and noise of the vehicle will increase.

[0070] Furthermore, in one embodiment, step S10 includes:

[0071] Substitute the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack into the first preset formula to calculate the temperature difference between the battery pack temperature and the battery pack inlet water temperature. The first preset formula is as follows:

[0072]

[0073] Among them, ΔT0 is used to represent the temperature difference between the battery pack temperature and the battery pack water inlet temperature, Q est It is used to indicate the total heat generation power of the battery pack, h is used to indicate the heat transfer coefficient of the battery pack, and S is used to indicate the heat transfer area of ​​the battery pack.

[0074] In this embodiment, under normal conditions, the battery mainly removes heat through convection heat exchange with the coolant. Without considering radiation heat exchange, if the battery temperature is to be kept balanced, the heat removed by the coolant should be equal to the heat generated by the battery pack. The total heat rate removed by the coolant is calculated by referring to Newton's law of cooling to obtain the formula Q exc =h*S*ΔT0, and the heat generation power of a single battery is the heat generated when the battery is discharged or charged, so Q exc =Q est .

[0075] In order to ensure that the total heat removed by the coolant can meet the battery heat dissipation requirements, the first preset formula can be calculated: Therefore, the total heat generation power of the battery pack, the heat transfer coefficient of the battery pack, and the heat transfer area of ​​the battery pack are substituted into the first preset formula The temperature difference between the battery pack temperature and the battery pack water inlet temperature that can maintain the balance of heat generation and heat dissipation of the battery pack can be calculated. Among them, ΔT0 is used to represent the temperature difference between the battery water inlet temperature and the battery temperature, Q est It is used to indicate the total heat generation power of the battery pack, h is used to indicate the heat transfer coefficient of the battery pack, and S is used to indicate the heat transfer area of ​​the battery pack. When the coolant flow rate is fixed, the product of the heat transfer coefficient of the battery pack and the heat transfer area of ​​the battery pack is a constant value.

[0076] Further, in one embodiment, referring to Figure 2 , Figure 2 For this application Figure 1 Detailed flow chart of step S20 in FIG. Figure 2 As shown, the step of determining the first correction coefficient and the second correction coefficient based on the battery pack temperature includes:

[0077] Step S201, determining a target temperature interval of the battery pack temperature among a plurality of preset temperature intervals;

[0078] Step S202, determining that a preset value corresponding to the target temperature range is a first correction coefficient;

[0079] Step S203, calculating the battery pack temperature change rate based on the battery pack temperature within a preset time period;

[0080] Step S204, determining a target temperature change rate interval in which the temperature change rate of the battery pack is located among a plurality of preset temperature change rate intervals;

[0081] Step S205: determine that the preset value corresponding to the target temperature change rate interval is a second correction coefficient.

[0082] In this embodiment, multiple temperature intervals are set, and after obtaining the battery pack temperature, a target temperature interval of the battery pack temperature is determined, and a preset value corresponding to the target temperature interval of the battery pack temperature is used as the first correction coefficient.

[0083] Specifically, the multiple preset temperature intervals include a first preset temperature interval: less than or equal to 35°C, a second preset temperature interval: greater than 35 degrees Celsius and less than or equal to 40°C, a third preset temperature interval: greater than 40°C and less than or equal to 45°C, and a fourth preset temperature interval: greater than 45°C. The preset value corresponding to the first preset temperature interval is 0°C, the preset value corresponding to the second preset temperature interval is 2°C, the preset value corresponding to the third preset temperature interval is 5°C, and the preset value corresponding to the fourth preset temperature interval is 15°C. If the current moment is t1, and the battery pack temperature at t1 is 38°C, then the second preset temperature interval where the battery pack temperature is at t1 is determined to be the target temperature interval, and further, the first correction coefficient is the preset value 2°C corresponding to the second preset temperature interval.

[0084] If the preset time length is the time length between time t0 and time t1, the battery pack temperature change rate between time t0 and time t1 is calculated based on the battery pack temperature at time t0, the battery pack temperature at time t1 and the time length between time t0 and time t1, wherein time t0 is the time before time t1.

[0085] Furthermore, in one embodiment, a temperature change curve is constructed based on the battery pack temperature during the period from time t0 to time t1, and the slope of the temperature change curve during this period is calculated, and the slope of the temperature change curve during this period is used as the battery pack temperature change rate.

[0086] After obtaining the battery pack temperature change rate in a plurality of preset temperature change rate intervals, a target temperature change rate interval in which the battery pack temperature change rate is located is determined, and a preset value corresponding to the target temperature change rate interval in which the battery pack temperature change rate is located is used as a second correction coefficient.

[0087] Specifically, the plurality of preset temperature change rate intervals include a first preset temperature change rate interval: less than or equal to -5°C / h, a second preset temperature change rate interval: greater than -5°C / h and less than or equal to -2°C / h, a third preset temperature change rate interval: greater than -2°C / h and less than or equal to 2°C / h, a fourth preset temperature change rate interval: greater than 2°C / h and less than or equal to 5°C / h, and a fifth preset temperature change rate interval: greater than 5°C / h. The preset value corresponding to the first preset temperature change rate interval is 0.6, the preset value corresponding to the second preset temperature change rate interval is 0.8, the preset value corresponding to the third preset temperature change rate interval is 0, the preset value corresponding to the fourth preset temperature change rate interval is 1.2, and the preset value corresponding to the fifth preset temperature change rate interval is 1.6. If the battery pack temperature change rate during the period from time t0 to time t1 is 3°C / h, the fourth preset temperature change rate interval in which the battery pack temperature change rate during the period from time t0 to time t1 is located is determined to be the target temperature change rate interval, and the second correction coefficient is determined to be the preset value 1.2 corresponding to the fourth preset temperature change rate interval. The first preset temperature interval is a suitable temperature interval, and when the battery pack temperature change rate is within the third preset temperature change rate interval, the battery pack temperature change is considered to be stable. It is easy to imagine that the parameters in this embodiment are only for illustration and are not limited here.

[0088] Furthermore, in one embodiment, step S30 includes:

[0089] Substitute the first correction coefficient, the second correction coefficient and the temperature difference into the second preset formula to calculate the target temperature difference. The second preset formula is as follows:

[0090]

[0091] Where, ΔT est It is used to represent the target temperature difference, A is used to represent the first correction coefficient, X is used to represent the second correction coefficient, and ΔT0 is used to represent the temperature difference between the battery pack temperature and the battery pack water inlet temperature.

[0092] In this embodiment, taking the temperature difference between the battery pack temperature and the battery pack water inlet temperature as 10°C as an example, if the first correction coefficient is 2°C, the second correction coefficient is 1.2, and the second correction coefficient is not equal to 0, the first correction coefficient, the second correction coefficient, and the temperature difference between the battery pack temperature and the battery pack water inlet temperature are substituted into the second preset formula ΔT est =A+X*ΔT0, calculate the target temperature difference ΔT est =2+1.2*10=14℃.

[0093] If the first correction coefficient is 2°C and the second correction coefficient is 0, the first correction coefficient, the second correction coefficient and the temperature difference between the battery pack temperature and the battery pack inlet water temperature are substituted into the second preset formula ΔT est =A+ΔT0+X*ΔT0, calculate the target temperature difference ΔT est =2+10+0*10=12℃.

[0094] If the first correction coefficient is 0°C, the second correction coefficient is 0.6, and the second correction coefficient is not equal to 0, then substitute the first correction coefficient, the second correction coefficient, and the temperature difference between the battery pack temperature and the battery pack water inlet temperature into the second preset formula ΔT est =A+ΔT0, calculate the target temperature difference ΔT est =0+0.6*10=6°C. The temperature difference between the battery pack temperature and the battery pack inlet water temperature is adjusted by the first correction coefficient and the second correction coefficient, so that when the battery temperature rises, the temperature difference increases, and when the battery temperature decreases, the temperature difference decreases.

[0095] Furthermore, in one embodiment, step S40 includes:

[0096] The difference between the battery pack temperature and the target temperature difference is calculated, and the difference is used as the target required water temperature.

[0097] In this embodiment, the battery pack temperature is 38°C, and the calculated temperature difference between the battery pack temperature and the battery pack water inlet temperature is 10°C. If the battery pack temperature change rate is -6°C / h, the first correction coefficient is 2°C, and the second correction coefficient is 0.6. The target temperature difference ΔT can be calculated. est =2+0.6*10=8. The target required water temperature is the difference between the battery pack temperature and the target temperature difference, that is, the target required water temperature is 38-8=30°C.

[0098] If the battery pack temperature change rate is 6°C / h, the first correction coefficient is 2°C, the second correction coefficient is 1.6, and the target temperature difference ΔT can be calculated est =2+1.6*10=18. The target required water temperature is the difference between the battery pack temperature and the target temperature difference, that is, the target required water temperature is 38-18=20°C.

[0099] It is easy to understand that when the battery pack temperature change rate is negative, the battery temperature decreases, and when the battery pack temperature change rate is positive, the battery temperature increases. When the battery temperature increases, the temperature difference increases, and the battery coolant temperature output by the water cooling unit decreases, thereby indirectly increasing the cooling power of the water cooling unit. When the battery temperature decreases, the temperature difference decreases, and the battery coolant temperature output by the water cooling unit increases, thereby indirectly reducing the cooling power of the water cooling unit, thereby stabilizing the battery temperature within an appropriate temperature range.

[0100] In a second aspect, an embodiment of the present application also provides a battery coolant temperature control device.

[0101] In one embodiment, referring to Figure 3 , Figure 3 This is a functional module diagram of an embodiment of a battery coolant temperature control device of the present application. Figure 3 As shown, the battery coolant temperature control device includes:

[0102] A first calculation module 10 is used to calculate the temperature difference between the battery pack temperature and the battery pack water inlet temperature based on the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack and the heat exchange area of ​​the battery pack, wherein the battery pack temperature is an average value of the temperatures of multiple single cells included in the battery pack;

[0103] A parameter determination module 20, configured to determine a first correction coefficient and a second correction coefficient based on the battery pack temperature;

[0104] A parameter adjustment module 30, configured to adjust the temperature difference based on the first correction coefficient and the second correction coefficient to obtain a target temperature difference;

[0105] The second calculation module 40 is used to calculate a target required water temperature based on the target temperature difference and the battery pack temperature, so that the water cooling unit can output battery coolant with the same target required water temperature.

[0106] Furthermore, in one embodiment, the first calculation module 10 is used to:

[0107] Substitute the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack into the first preset formula to calculate the temperature difference between the battery pack temperature and the battery pack inlet water temperature. The first preset formula is as follows:

[0108]

[0109] Among them, ΔT0 is used to represent the temperature difference between the battery pack temperature and the battery pack water inlet temperature, Q est It is used to indicate the total heat generation power of the battery pack, h is used to indicate the heat transfer coefficient of the battery pack, and S is used to indicate the heat transfer area of ​​the battery pack.

[0110] Furthermore, in one embodiment, the parameter determination module 20 is used to:

[0111] Determining a target temperature interval for the battery pack temperature among a plurality of preset temperature intervals;

[0112] Determine a preset value corresponding to the target temperature range as a first correction coefficient;

[0113] The battery pack temperature change rate is calculated based on the battery pack temperature within a preset time period;

[0114] Determining a target temperature change rate interval in which the battery pack temperature change rate is located among a plurality of preset temperature change rate intervals;

[0115] A preset value corresponding to the target temperature change rate interval is determined as a second correction coefficient.

[0116] Furthermore, in one embodiment, the parameter adjustment module 30 is used to:

[0117] Substitute the first correction coefficient, the second correction coefficient and the temperature difference into the second preset formula to calculate the target temperature difference. The second preset formula is as follows:

[0118]

[0119] Where, ΔT est It is used to represent the target temperature difference, A is used to represent the first correction coefficient, X is used to represent the second correction coefficient, and ΔT0 is used to represent the temperature difference between the battery pack temperature and the battery pack water inlet temperature.

[0120] Furthermore, in one embodiment, the second calculation module 40 is used to:

[0121] The difference between the battery pack temperature and the target temperature difference is calculated, and the difference is used as the target required water temperature.

[0122] Among them, the functional implementation of each module in the above-mentioned battery coolant temperature control device corresponds to the various steps in the above-mentioned battery coolant temperature control method embodiment, and its functions and implementation processes are no longer repeated here.

[0123] In a third aspect, an embodiment of the present application provides a battery coolant temperature control device.

[0124] Reference Figure 4 , Figure 4 Schematic diagram of the hardware structure of the battery coolant temperature control device involved in the embodiment of the present application. In the embodiment of the present application, the battery coolant temperature control device may include a processor, a memory, a communication interface and a communication bus.

[0125] The communication bus may be of any type and is used to interconnect the processor, the memory, and the communication interface.

[0126] The communication interface includes an input / output (I / O) interface, a physical interface, and a logical interface, etc., which are used to interconnect the devices inside the battery coolant temperature control device, and an interface for interconnecting the battery coolant temperature control device with other devices (such as other computing devices or user devices). The physical interface can be an Ethernet interface, an optical fiber interface, an ATM interface, etc.; the user device can be a display, a keyboard, etc.

[0127] The memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0128] The processor may be a general-purpose processor, and the general-purpose processor may call the battery coolant temperature control program stored in the memory and execute the battery coolant temperature control method provided in the embodiment of the present application. For example, the general-purpose processor may be a central processing unit (CPU). The method executed when the battery coolant temperature control program is called may refer to the various embodiments of the battery coolant temperature control method of the present application, and will not be repeated here.

[0129] Those skilled in the art will understand that Figure 4 The hardware structure shown in the figure does not constitute a limitation on the present application, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0130] In a fourth aspect, an embodiment of the present application also provides a readable storage medium.

[0131] The readable storage medium of the present application stores a battery coolant temperature control program, wherein when the battery coolant temperature control program is executed by the processor, the steps of the battery coolant temperature control method as described above are implemented.

[0132] Among them, the method implemented when the battery coolant temperature control program is executed can refer to the various embodiments of the battery coolant temperature control method of the present application, and will not be repeated here.

[0133] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0134] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, disk, CD) as described above, and includes a number of instructions for a terminal device to execute the methods described in each embodiment of the present application.

[0135] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A battery coolant temperature control method, characterized in that: The battery coolant temperature control method comprises: The temperature difference between the battery pack temperature and the battery pack inlet water temperature is calculated based on the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack, wherein the battery pack temperature is the average temperature of multiple single cells included in the battery pack; determining a first correction factor and a second correction factor based on the battery pack temperature; Adjusting the temperature difference based on the first correction coefficient and the second correction coefficient to obtain a target temperature difference; Calculating a target required water temperature based on the target temperature difference and the battery pack temperature so that the water cooling unit can output battery coolant with the same target required water temperature; The step of determining the first correction coefficient and the second correction coefficient based on the battery pack temperature includes: Determining a target temperature interval for the battery pack temperature among a plurality of preset temperature intervals; Determine a preset value corresponding to the target temperature range as a first correction coefficient; The battery pack temperature change rate is calculated based on the battery pack temperature within a preset time period; Determining a target temperature change rate interval in which the battery pack temperature change rate is located among a plurality of preset temperature change rate intervals; Determine a preset value corresponding to the target temperature change rate interval as a second correction coefficient; The step of adjusting the temperature difference based on the first correction coefficient and the second correction coefficient to obtain a target temperature difference includes: Substitute the first correction coefficient, the second correction coefficient and the temperature difference into the second preset formula to calculate the target temperature difference. The second preset formula is as follows: Where, ΔT est It is used to represent the target temperature difference, A is used to represent the first correction coefficient, X is used to represent the second correction coefficient, and ΔT0 is used to represent the temperature difference between the battery pack temperature and the battery pack water inlet temperature.

2. The battery coolant temperature control method according to claim 1, characterized in that: The step of calculating the temperature difference between the battery pack temperature and the battery pack inlet water temperature based on the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack comprises: Substitute the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack into the first preset formula to calculate the temperature difference between the battery pack temperature and the battery pack inlet water temperature. The first preset formula is as follows: Among them, ΔT0 is used to represent the temperature difference between the battery pack temperature and the battery pack water inlet temperature, Q est It is used to indicate the total heat generation power of the battery pack, h is used to indicate the heat transfer coefficient of the battery pack, and S is used to indicate the heat transfer area of ​​the battery pack.

3. The battery coolant temperature control method according to claim 1, characterized in that: The step of calculating the target required water temperature based on the target temperature difference and the battery pack temperature includes: The difference between the battery pack temperature and the target temperature difference is calculated, and the difference is used as the target required water temperature.

4. A battery coolant temperature control device, characterized in that: The battery coolant temperature control device comprises: A first calculation module, configured to calculate a temperature difference between a battery pack temperature and a battery pack water inlet temperature based on a total heat generation power of the battery pack, a heat exchange coefficient of the battery pack, and a heat exchange area of ​​the battery pack, wherein the battery pack temperature is an average value of temperatures of a plurality of single cells included in the battery pack; A parameter determination module, used to determine a target temperature interval in which the battery pack temperature is located among a plurality of preset temperature intervals; determine a preset value corresponding to the target temperature interval as a first correction coefficient; calculate a battery pack temperature change rate based on the battery pack temperature within a preset time period; determine a target temperature change rate interval in which the battery pack temperature change rate is located among a plurality of preset temperature change rate intervals; determine a preset value corresponding to the target temperature change rate interval as a second correction coefficient; The parameter adjustment module is used to substitute the first correction coefficient, the second correction coefficient and the temperature difference into a second preset formula to calculate the target temperature difference. The second preset formula is as follows: Where, ΔT est It is used to represent the target temperature difference, A is used to represent the first correction coefficient, X is used to represent the second correction coefficient, and ΔT0 is used to represent the temperature difference between the battery pack temperature and the battery pack water inlet temperature; The second calculation module is used to calculate a target required water temperature based on the target temperature difference and the battery pack temperature, so that the water cooling unit can output battery coolant with the same target required water temperature.

5. The battery coolant temperature control device according to claim 4, characterized in that: The first computing module is used for: Substitute the total heat generation power of the battery pack, the heat exchange coefficient of the battery pack, and the heat exchange area of ​​the battery pack into the first preset formula to calculate the temperature difference between the battery pack temperature and the battery pack inlet water temperature. The first preset formula is as follows: Among them, ΔT0 is used to represent the temperature difference between the battery pack temperature and the battery pack water inlet temperature, Q est It is used to indicate the total heat generation power of the battery pack, h is used to indicate the heat transfer coefficient of the battery pack, and S is used to indicate the heat transfer area of ​​the battery pack.

6. A battery coolant temperature control device, characterized in that: The battery coolant temperature control device includes a processor, a memory, and a battery coolant temperature control program stored in the memory and executable by the processor, wherein when the battery coolant temperature control program is executed by the processor, the steps of the battery coolant temperature control method according to any one of claims 1 to 3 are implemented.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a battery coolant temperature control program, wherein when the battery coolant temperature control program is executed by a processor, the steps of the battery coolant temperature control method according to any one of claims 1 to 3 are implemented.

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