Method and system for battery thermal management, and vehicle

Abstract

Techniques described herein relate to methods and systems for battery thermal management, and a vehicle. The battery thermal management method comprises the following steps: acquiring historical measurement data of battery temperature in a period of time; determining statistical data of the battery temperature based on the historical measurement data; one or more temperature management limits for thermal management of the battery are determined based on statistics of the battery temperature. The battery thermal management method of the present disclosure manages the battery temperature using a statistical method and dynamically determines a management limit based on historical statistical data of the battery temperature. Compared with a method for setting a static threshold value for the battery temperature, the battery thermal management method disclosed by the invention takes factors such as battery aging and vehicle inherent characteristics into account when the management and control limit value is determined, so that potential thermal defects are detected as only system disturbance and introduction factors, and the accuracy and robustness of battery detection are improved.

Description

Technical Field

[0001] The present application relates generally to thermal management, and more particularly to methods and systems for thermal management of batteries, and vehicles. Background Art

[0002] The market for new energy vehicles (e.g., electric vehicles and hybrid vehicles) continues to expand rapidly. Both electric vehicles and hybrid vehicles include high-voltage batteries. As a core component of new energy vehicles, high-voltage batteries are a complex electrical system that includes power batteries, mechanical structures, high-voltage modules, and more.

[0003] From the perspective of safety, according to relevant statistics, deformation of high-voltage batteries (e.g., power battery packs) is one of the important causes of vehicle safety accidents. For example, mechanical impact may cause deformation of high-voltage batteries, which may further deform the battery module over time, causing leakage, rust, and short circuits of battery cells, etc., thus causing safety accidents. In terms of cost, high-voltage batteries account for a large part of the total cost of a vehicle, equivalent to 30% to 40% of the total price of a new vehicle. Ensuring that high-voltage batteries can output power stably for as long as possible can maximize cost-effectiveness.

[0004] Therefore, it is desirable to provide a method for accurately and efficiently testing batteries. Summary of the invention

[0005] In view of one or more of the above problems, the present disclosure provides a method and system for battery thermal management, and a vehicle.

[0006] In a first aspect, the present disclosure provides a battery thermal management method, which may include: obtaining historical measurement data of battery temperature over a period of time; determining statistical data of the battery temperature based on the historical measurement data; and determining one or more temperature control limits for battery thermal management based on the statistical data of the battery temperature.

[0007] According to one embodiment of the present application, optionally, the statistical data of the battery temperature may include: a plurality of temperature averages at a plurality of monitoring times within a period of time, wherein each of the plurality of temperature averages is an average value of the battery temperature respectively measured by a plurality of temperature sensors; and / or a plurality of temperature standard deviations at a plurality of monitoring times within a period of time, wherein each of the plurality of temperature standard deviations is a standard deviation of the battery temperature respectively measured by a plurality of temperature sensors.

[0008] According to one embodiment of the present application, optionally, the statistical data of the battery temperature may further include: an average of multiple temperature averages and an average of multiple temperature standard deviations, wherein determining one or more temperature control limits for battery thermal management further includes: taking the average of the multiple temperature averages as the central reference, determining one or more temperature control limits based on the statistical probability of abnormal battery temperature fluctuations.

[0009] According to one embodiment of the present application, optionally, the statistical data of the battery temperature may include: an average value of multiple temperature standard deviations, wherein determining one or more temperature control limits for battery thermal management further includes: taking the average value of multiple temperature standard deviations as a central reference, determining one or more temperature control limits based on the statistical probability of abnormal battery temperature fluctuations.

[0010] According to one embodiment of the present application, optionally, the battery thermal management method may further include: when one of the one or more temperature control limits is ≤ a first threshold, determining that the battery is deformed when a first number of consecutive measured temperature averages are outside the one or more temperature control limits.

[0011] According to one embodiment of the present application, optionally, the battery thermal management method may further include: when a first threshold value < one of the one or more temperature control limits ≤ a second threshold value, determining that the battery is deformed when a second number of consecutive measured temperature averages are outside the one or more temperature control limits, wherein the first number is greater than the second number.

[0012] According to one embodiment of the present application, optionally, the battery thermal management method may further include: when the second threshold value < one of the one or more temperature control limits, when the third threshold value < the ratio between the first temperature control limit and the second temperature control limit, determining that the battery is deformed, wherein the first temperature control limit is determined based on multiple temperature averages within a recent first period of time, and the second temperature control limit is determined based on multiple temperature averages within a recent second period of time, and the first period of time is longer than the second period of time.

[0013] In a second aspect, the present disclosure provides a battery thermal management system. The battery thermal management system may include: a plurality of temperature sensors for measuring battery temperature; and a control unit. The control unit may be configured to: obtain historical measurement data of battery temperature measured by the plurality of temperature sensors over a period of time; determine statistical data of battery temperature based on the historical measurement data; and determine one or more temperature control limits for battery thermal management based on the statistical data of battery temperature.

[0014] According to an embodiment of the present application, optionally, a plurality of temperature sensors may be evenly distributed on each module of the battery.

[0015] According to one embodiment of the present application, optionally, the statistical data of the battery temperature may include: a plurality of temperature averages at a plurality of monitoring times within a period of time, wherein each of the plurality of temperature averages is an average value of the battery temperature respectively measured by a plurality of temperature sensors; and / or a plurality of temperature standard deviations at a plurality of monitoring times within a period of time, wherein each of the plurality of temperature standard deviations is a standard deviation of the battery temperature respectively measured by a plurality of temperature sensors.

[0016] According to one embodiment of the present application, optionally, the statistical data of the battery temperature may further include: an average of multiple temperature averages and an average of multiple temperature standard deviations, wherein determining one or more temperature control limits for battery thermal management further includes: taking the average of the multiple temperature averages as the central reference, determining one or more temperature control limits based on the statistical probability of abnormal battery temperature fluctuations.

[0017] According to one embodiment of the present application, optionally, the statistical data of the battery temperature may include: an average value of multiple temperature standard deviations, wherein determining one or more temperature control limits for battery thermal management further includes: taking the average value of multiple temperature standard deviations as a central reference, determining one or more temperature control limits based on the statistical probability of abnormal battery temperature fluctuations.

[0018] According to one embodiment of the present application, optionally, the control unit may be further configured to: when a temperature control limit among one or more temperature control limits is ≤ a first threshold value, the battery is determined to be deformed when a first number of consecutive measured temperature averages are outside the one or more temperature control limits; or when a first threshold value is < a temperature control limit among one or more temperature control limits ≤ a second threshold value, the battery is determined to be deformed when a second number of consecutive measured temperature averages are outside the one or more temperature control limits, wherein the first number is greater than the second number.

[0019] According to one embodiment of the present application, optionally, the control unit may be further configured to: determine that the battery is deformed when the second threshold value is < one of the one or more temperature control limits, and when the third threshold value is < the ratio between the first temperature control limit and the second temperature control limit, wherein the first temperature control limit is determined based on multiple temperature averages within a recent first period of time, and the second temperature control limit is determined based on multiple temperature averages within a recent second period of time, and the first period of time is longer than the second period of time.

[0020] In a third aspect, the present disclosure provides a vehicle. The vehicle may include: a battery; and the battery thermal management system as described above.

[0021] The battery thermal management method disclosed in the present invention uses a statistical method to manage the battery temperature and dynamically determines the control limit based on the historical statistical data of the battery temperature. Compared with setting a static threshold for the battery temperature, the battery thermal management method disclosed in the present invention takes into account factors such as battery aging and vehicle inherent characteristics when determining the control limit, so as to detect potential thermal defects as only system disturbances and introduction factors, thereby improving the accuracy and robustness of battery detection.

[0022] These and other features and advantages will become apparent by reading the following detailed description and by reference to the associated drawings.It is to be understood that the foregoing general description and the following detailed description are illustrative only and are not restrictive of the aspects of what is claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to understand in detail the manner in which the above features of the present disclosure are used, the above briefly summarized contents may be described in more detail with reference to various embodiments, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings only show certain typical aspects of the present disclosure and should not be considered to limit its scope, as the description may allow for other equally effective aspects.

[0024] Figure 1 A schematic diagram of a high voltage battery is shown.

[0025] Figure 2 An exemplary arrangement diagram of arranging a plurality of sensors on a high-voltage battery according to an embodiment of the present disclosure is shown.

[0026] Figure 3 Another example arrangement diagram of arranging a plurality of sensors on a high-voltage battery according to an embodiment of the present disclosure is shown.

[0027] Figure 4 A flow chart of a method for battery thermal management according to an embodiment of the present disclosure is shown.

[0028] Figure 5 A control schematic including multiple control limits is shown.

[0029] Figure 6 A schematic diagram of determining one or more control limits using a statistical method according to an embodiment of the present disclosure is shown.

[0030] Figure 7 A flow chart of a method for determining one or more control limits for different vehicles according to an embodiment of the present disclosure is shown.

[0031] Figure 8A block diagram of a battery thermal management system according to an embodiment of the present disclosure is shown.

[0032] Fig. 9 A block diagram of a vehicle including a battery thermal management system according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0033] In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the described embodiments. However, it will be apparent to those skilled in the art that the described embodiments may be practiced without some or all of these specific details. In other embodiments, well-known structures or processing steps are not described in detail to avoid unnecessarily obscuring the concepts of the present disclosure.

[0034] In the description of the embodiments of the present disclosure, it should be noted that, unless otherwise specified, the term "plurality" means more than two; the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone; the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship. In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field of the present disclosure; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure; the terms "including" and "having" in the specification and claims of the present disclosure and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusion.

[0036] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present disclosure. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0037] In the following description, numerous specific details (such as examples of specific components, circuits, and processes) are set forth to provide a thorough understanding of the present disclosure. As used herein, the terms "coupled," "coupled," "connected," or "connected" mean directly connected to, or connected through one or more intermediary media or components. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure may be understood as the specific circumstances. Moreover, in the following description and for the purpose of explanation, specific naming is set forth to provide a thorough understanding of the various embodiments of the present disclosure. However, it will be apparent to those skilled in the art that each example embodiment may be practiced without these specific details. In other examples, well-known circuits and devices are shown in block diagram form to avoid confusing the present disclosure.

[0038] For simplicity, the present disclosure is described in conjunction with a “vehicle” in the specification, but the “vehicle” of the embodiments described herein is not limited to vehicles but may also be applicable to any other type of transportation vehicle using a high-voltage battery without departing from the scope of the present disclosure.

[0039] As a core component of new energy vehicles, the safety of high-voltage batteries is one of the key factors to ensure the normal driving of new energy vehicles. A common way to monitor the working state of high-voltage batteries is to use a temperature sensor to measure the temperature of the high-voltage battery and judge the working state of the high-voltage battery by the temperature threshold. In actual use, there are many reasons for battery thermal defects. As an example, the battery gradually ages over time, and the number of cycle charging increases, which may also cause the temperature of the high-voltage battery to rise. Although the battery temperature rises, this type of temperature rise is a phenomenon that occurs during the natural use of the battery. As another example, certain unexpected impacts may cause the high-voltage battery to deform, causing the high-voltage battery temperature to rise, making the high-voltage battery unable to output power stably. If the battery is allowed to continue to work without timely maintenance or replacement, it may cause safety accidents over time. Therefore, when monitoring the battery temperature, a battery monitoring method that can accurately detect potential thermal defects as factors introduced by accidental impacts, system disturbances, etc., rather than natural aging during use, is desired.

[0040] Therefore, in order to solve one or more of the above problems, the present disclosure proposes a battery thermal management method. The thermal management method of the present disclosure obtains a large amount of battery temperature data, and uses statistical methods (e.g., statistical process control (SPC) charts) to process these battery temperature data to determine one or more temperature control limits of the battery temperature. Different from setting static thresholds only for the monitored direct temperature sensor values ​​or indirect temperature characteristic values ​​(e.g., maximum value, minimum value, median value or difference range value, etc.), the battery thermal management method of the present disclosure uses statistical methods to dynamically determine the limits based on the temperature measurement data over time. The dynamic limits take into account factors such as battery aging and inherent characteristics of the vehicle to detect potential thermal defects as only system disturbances and introduction factors, thereby improving the accuracy of battery monitoring. In addition, the control limits are very suitable for the behavior of the vehicle / battery itself, ensuring robustness. In addition, the battery thermal management method of the present disclosure determines dynamic limits that vary from vehicle to vehicle for different vehicles to adapt to different vehicle characteristics, further improving the accuracy of battery monitoring. The following will specifically describe the automatic driving control system for vehicles in conjunction with the accompanying drawings and list some embodiments to describe some application scenarios.

[0041] Figure 1 An example schematic diagram of a high voltage battery 100 is shown. Figure 1 In the example shown in , the high-voltage battery 100 may include 4 battery modules (DM) 110. Each battery module 110 may include 2 battery cells (SM) 105. In some embodiments, in order to achieve accurate monitoring of the high-voltage battery, multiple temperature sensors may be arranged at each battery cell. The temperature sensor may be any type of temperature sensor, including but not limited to: a thermistor sensor, a thermocouple sensor, a platinum thermistor temperature sensor, and a digital output sensor, etc., which is not limited in this application. For ease of description, the thermistor sensor is used as an example for explanation below. Those skilled in the art will appreciate that any other type of temperature sensor may also be used to measure the temperature without departing from the scope of the present disclosure.

[0042] In some embodiments, multiple temperature sensors may be evenly distributed on each module of the battery. As an example, Figure 2 An example arrangement diagram 200 of arranging a plurality of thermistor sensors on a high voltage battery 100 is shown. Figure 2 As shown in , a thermistor sensor can be arranged on each battery cell, and a total of 8 thermistor sensors R1-R8 can be arranged. As another example, Figure 3 An example arrangement diagram 300 of arranging a plurality of thermistor sensors on a high voltage battery 100 is shown. Figure 3As shown in , three thermistor sensors can be arranged on each battery cell, and a total of 24 thermistor sensors R11-R13, R21-R23, R31-R33, R41-R43, R51-R53, R61-R63, R71-R73, R81-R83 are arranged. Those skilled in the art will appreciate that the above arrangement of thermistor sensors is only shown as an example, and the thermistor sensors can be arranged in any other way without departing from the scope of the present disclosure. In addition, it is worth noting that the temperature measurement value can be obtained directly from the temperature sensor installed on the high-voltage battery, or can be obtained via the real-time monitoring system (RTM) of the vehicle, and this application is not limited to this.

[0043] Figure 4 FIG. 4 is a flow chart of a method 400 for battery thermal management according to an embodiment of the present disclosure. Figure 2 The arrangement of thermistor temperature sensors R1-R8 shown in FIG. 4 is used as an example to illustrate the method 400 for battery thermal management. Figure 4 As shown in , a method 400 for battery thermal management may include the following steps.

[0044] In step 402, historical measurement data of the battery temperature within a period of time may be obtained. For example, the battery temperature within a period of time (e.g., 22 months) may be obtained. Figure 2 Historical measurement data of sensor readings (Ohms) measured by thermistor temperature sensors R1-R8 shown in , as shown in columns R1-R8 in Table 1 below.

[0045] At step 404 , statistics of battery temperature may be determined based on historical measurement data.

[0046] In one embodiment, the statistical data of the battery temperature may include: multiple temperature averages at multiple monitoring times within a period of time, wherein each of the multiple temperature averages is an average value of the battery temperature measured by multiple temperature sensors. For example, the statistical data of the battery temperature may include: 22 temperature averages measured periodically in each of 22 months, as shown in the 10th column R average value in Table 1 below. Each of the 22 temperature averages is an average value of the battery temperature measured by temperature sensors R1-R8, respectively. For example, each temperature average can be calculated by the following formula: The calculated average temperature value is shown in the R average value in the 10th column of Table 1 below.

[0047] In another embodiment, the statistical data of the battery temperature may include: a plurality of temperature standard deviations at a plurality of monitoring times within a period of time, wherein each of the plurality of temperature standard deviations is a standard deviation of the battery temperature measured by a plurality of temperature sensors, respectively. For example, the statistical data of the battery temperature may include: a plurality of temperature standard deviations measured periodically within each of 22 months, as shown in the standard deviation in the 11th column of Table 1 below. Each of the 22 temperature standard deviations is a standard deviation of the battery temperature measured by temperature sensors R1-R8, respectively. For example, each temperature standard deviation may be calculated by the following formula: The calculated temperature standard deviation is shown in the standard deviation column 11 in Table 1 below.

[0048] In yet another embodiment, the statistical data of the battery temperature may include: a plurality of temperature average values ​​and a plurality of temperature standard deviations as described above.

[0049] In an optional embodiment, the statistical data of the battery temperature may further include: an average of a plurality of temperature average values ​​and an average of a plurality of temperature standard deviations.

[0050] In another optional embodiment, the statistical data of the battery temperature may further include: an average value of a plurality of temperature standard deviations.

[0051] NO. R1 R2 R3 R4 R5 R6 R7 R8 R-mean Standard Deviation 1 0.55 0.18 0.13 0.08 0.09 0.12 0.00 0.69 0.23 0.25 2 0.28 0.04 0.02 0.12 0.21 0.03 0.32 0.45 0.18 0.16 3 0.13 0.09 0.12 0.20 0.22 0.20 0.19 0.46 0.20 0.11 4 0.10 0.16 0.17 0.19 0.27 0.23 0.25 0.38 0.22 0.08 5 0.09 0.25 0.26 0.16 0.16 0.16 0.20 0.39 0.21 0.09 6 0.11 0.27 0.27 0.16 0.09 0.15 0.23 0.38 0.21 0.10 7 0.13 0.25 0.25 0.15 0.10 0.16 0.20 0.35 0.20 0.08 8 0.14 0.25 0.23 0.14 0.06 0.17 0.18 0.36 0.19 0.09 9 0.17 0.22 0.22 0.15 0.03 0.14 0.15 0.36 0.18 0.09 10 0.20 0.11 0.19 0.10 0.01 0.14 0.13 0.35 0.15 0.10 11 0.22 0.00 0.11 0.13 0.12 0.17 0.17 0.42 0.17 0.12 12 0.21 0.02 0.13 0.14 0.10 0.15 0.17 0.42 0.17 0.12 13 0.19 0.02 0.05 0.02 0.02 0.10 0.25 0.37 0.13 0.13 14 0.14 0.12 0.28 0.19 0.05 0.11 0.15 0.39 0.18 0.11 15 0.12 0.18 0.36 0.20 0.07 0.11 0.17 0.44 0.21 0.13 16 0.09 0.33 0.59 0.19 0.08 0.03 0.16 0.44 0.24 0.20 17 0.03 0.48 0.88 0.10 0.13 0.03 0.11 0.48 0.28 0.30 18 0.10 0.74 1.11 0.02 0.04 0.06 0.11 0.54 0.34 0.41 19 0.16 0.68 0.97 0.08 0.16 0.03 0.17 0.47 0.34 0.34 20 0.32 0.93 1.21 0.32 0.34 0.04 0.27 0.38 0.48 0.39 21 0.13 0.52 0.65 0.16 0.19 0.01 0.11 0.21 0.25 0.22 22 0.02 0.29 0.37 0.06 0.16 0.23 0.24 0.00 0.17 0.13 0.22 0.17

[0052] Table 1

[0053] At step 406 , one or more temperature control limits for battery thermal management may be determined based on the battery temperature statistics.

[0054] In an optional embodiment where the statistical data of the battery temperature may include an average of multiple temperature averages and an average of multiple temperature standard deviations, the method 400 may further include: taking the average of the multiple temperature averages as a central reference, and determining one or more temperature control limits based on the statistical probability of abnormal battery temperature fluctuations. In an optional embodiment where the statistical data of the battery temperature may include an average of multiple temperature standard deviations, the method 400 may further include: taking the average of the multiple temperature standard deviations as a central reference, and determining one or more temperature control limits based on the statistical probability of abnormal battery temperature fluctuations.

[0055] Fluctuation means that no two things are exactly the same in real life. Fluctuation includes normal fluctuation and abnormal fluctuation. Normal fluctuation is caused by common (accidental) causes. Common (accidental) causes refer to the causes of many variations in a process with a stable and repeatable distribution over time. Normal fluctuation cannot be controlled and can only be controlled within the tolerance range. Abnormal fluctuation is caused by special (abnormal) causes. Special (abnormal) causes refer to the causes of variation that are inappropriate for the process, that is, when they occur, they will cause the distribution of the entire process to change. The fluctuation caused by special abnormal fluctuation is large and easy to find, and should be found and corrected. Assuming that the process is in a controlled state, once it deviates from this state, it is very likely that the process is out of control and needs to be adjusted in time. The basic reason for the application of statistical process control (SPC) is that low-probability events are impossible to occur in a single test (referring to events with a very small chance of occurrence); the process distribution is a normal distribution. If the sample size is large enough, for any population, the sampling distribution of the sample mean is similar to the normal distribution. No matter what the distribution of the population is, it always presents a normal distribution or an approximate normal distribution. From the properties of normal distribution, we know that the data appears in The probability of something other than this is only 0.27%. This is a low-probability event. According to the principle of probability theory that "low-probability events are considered to be practically impossible", it can be considered that the event that occurs Events outside the interval are abnormal fluctuations, which occur because abnormal reasons cause the overall distribution to deviate from the normal position. Shewhart believes that is the control limit (CONTROLLIMIT, CL). That is, the width of the control limit is determined to be 3σ according to this principle. Figure 5 5 shows a control principle diagram including multiple control limits, wherein the multiple control limits include an upper control limit (UPPER CONTROL LIMIT, UCL) 505, a control limit 510, and a lower control limit (LOWER CONTROL LIMIT, LCL) 515. Figure 5 As shown in The fluctuations within the range (i.e., the fluctuations between the upper control limit UCL 505 and the lower control limit LCL 515 are the range of fluctuations caused by common reasons; and those falling within Fluctuations outside the range (i.e., fluctuations above the upper control limit UCL 505 or below the lower control limit LCL 515) are the range of fluctuations caused by special causes. Thus, one or more temperature control limits may be It is worth noting that the above-mentioned method of determining the control limit is only provided as an example, and other methods of determining the control limit may also be used without departing from the scope of the present disclosure.

[0056] Figure 6A schematic diagram of determining one or more control limits using a statistical method according to an embodiment of the present disclosure is shown.

[0057] As an example, according to the historical measurement data of the battery temperature shown in Table 1, in an optional embodiment in which the statistical data of the battery temperature may include an average value of a plurality of temperature average values ​​(e.g., 0.22, as shown in Table 1 above) and an average value of a plurality of temperature standard deviations (e.g., 0.17, as shown in Table 1 above), according to the statistical process control chart, the temperature control limit value may be determined as 0.2234, the upper temperature control limit value may be determined as 0.4108, and the lower temperature control limit value may be determined as 0.0360, as shown in Table 1 above. Figure 6 As shown in the graph 605 in FIG. 605. In some cases, when the temperature control limit = the average of multiple temperature average values, the upper temperature control limit = the average of multiple temperature average values ​​+ the coefficient A * the average of multiple temperature standard deviations, and the lower temperature control limit = the average of multiple temperature average values ​​- the coefficient A * the average of multiple temperature standard deviations, the coefficient A can be determined to be 1.099.

[0058] As another example, according to the historical measurement data of the battery temperature shown in Table 1, in an optional embodiment where the statistical data of the battery temperature may include an average value of multiple temperature standard deviations (e.g., 0.17, as shown in Table 1 above), according to the statistical process control chart, the temperature standard deviation control limit may be determined as 0.1705, the upper temperature standard deviation control limit may be determined as 0.3095, and the lower temperature standard deviation control limit may be determined as 0.0316, as shown in Table 1 above. Figure 6 As shown in the graph 610 in FIG. In some cases, when the temperature standard deviation control limit value = the average value of multiple temperature standard deviations, the upper temperature standard deviation control limit value = the coefficient B*the average value of multiple temperature standard deviations, and the lower temperature standard deviation control limit value = the coefficient C*the average value of multiple temperature standard deviations, the coefficient B can be determined to be 1.815, and the coefficient C can be determined to be 0.185.

[0059] Those skilled in the art will appreciate that, in actual use, a combination of temperature control limits and standard deviation control limits may be used to determine abnormal fluctuations. In some cases, the determined coefficients may be used to determine one or more temperature control limits. The coefficients may be adjusted according to the false negative rate and the false positive rate. It is worth noting that the above-mentioned method of determining the coefficients is provided only as an example, and other methods of determining the coefficients may also be used without departing from the scope of the present disclosure.

[0060] According to the method for battery thermal management as described above, the temperature control limit is determined based on the historical measurement data of the battery temperature. Compared with setting a static threshold for the battery temperature, the method for battery thermal management disclosed in the present invention takes into account factors such as battery aging when determining the control limit to detect potential thermal defects as only abnormal fluctuations (e.g., system disturbances, introduced factors, etc.), thereby improving the accuracy of battery detection. The above-mentioned time period for measuring the battery temperature is selected only as an example, and those skilled in the art will appreciate that the time period for measuring the battery temperature can be selected synchronously, and the temperature control limit can be continuously updated. For example, the temperature control limit can be updated every year, or the temperature control limit can be updated every 3 years, and the present disclosure is not limited to this.

[0061] Figure 7 A flow chart of a method 700 for determining one or more control limits for different vehicles according to an embodiment of the present disclosure is shown. The method 700 may further include determining one or more rules for determining whether a battery is deformed according to a range to which one of the one or more temperature control limits belongs. The method 700 may start at box 702.

[0062] In an optional embodiment, the battery thermal management method may further include determining in box 704 that when one of the one or more temperature control limits is ≤ a first threshold, further determining in box 706 that a first number of consecutive measured temperature averages are outside the one or more temperature control limits, then determining that the battery is deformed in box 716. For example, according to the historical measurement data of the battery temperature shown in Table 1, when the upper temperature control limit is ≤ a first threshold, when a first number of consecutive measured temperature averages are outside the one or more temperature control limits, it is determined that the battery is deformed, wherein the first threshold is 0.1-0.5, preferably 0.25 or 0.3, and the first number is 3-7, preferably 4 or 5.

[0063] In an optional embodiment, the battery thermal management method may further include determining in box 708 that the first threshold < one of the one or more temperature control limits ≤ the second threshold, further determining in box 710 that the second number of consecutive measured temperature averages are outside the one or more temperature control limits, and then determining in box 716 that the battery is deformed, wherein the first number is greater than the second number. For example, according to the historical measurement data of the battery temperature shown in Table 1, when the first threshold < the upper temperature control limit ≤ the second threshold, when the second number of consecutive measured temperature averages are outside the one or more temperature control limits, it is determined that the battery is deformed, wherein the second threshold is 0.5-1.2, the second threshold is greater than the first threshold, the second number is 1-3, preferably 2 or 3, and the second number is less than the first number.

[0064] In an optional embodiment, the battery thermal management method may further include determining in box 712 that the second threshold value is less than one of the one or more temperature control limits, further determining in box 714 that the third threshold value is less than the ratio between the first temperature control limit value and the second temperature control limit value, and then determining in box 716 that the battery is deformed, wherein the first temperature control limit value is determined based on a plurality of temperature average values ​​within a recent first period of time, and the second temperature control limit value is determined based on a plurality of temperature average values ​​within a recent second period of time, and the first period of time is longer than the second period of time. For example, according to the historical measurement data of the battery temperature shown in Table 1, when the second threshold value is less than the upper temperature control limit value, when the third threshold value is less than the ratio between the first temperature control limit value and the second temperature control limit value, it is determined that the battery is deformed, wherein the first temperature control limit value is determined based on a plurality of temperature average values ​​within the previous 12-48 months, and the second temperature control limit value is determined based on a plurality of temperature average values ​​within the previous 6-24 months, wherein the second threshold value is 0.5-1.2, preferably 0.6, 1, and the third threshold value is 120%-180%, preferably 138% or 150%.

[0065] The above thresholds are provided only as examples, and different thresholds may be used adaptively without departing from the scope of the present disclosure. In some cases, the thresholds may be dynamically adjusted according to the false negative rate and false positive rate of the current battery management method. According to the method for battery thermal management as described above, the temperature control limit is customized for different vehicles. After the temperature control limit is dynamically determined according to the historical measurement data of the battery temperature, different rules for determining abnormal fluctuations in detection may be determined for the inherent characteristics of different vehicles. For example, when the upper temperature control limit is ≤ the first threshold, it means that the statistical data of the battery temperature shows that the state of the battery temperature is very stable, so when the average value of the temperature measured for the first number of consecutive times is outside one or more temperature control limits, it is determined that the battery is deformed, thereby increasing the robustness of the battery thermal management. For another example, when the first threshold < the upper temperature control limit ≤ the second threshold, it means that the statistical data of the battery temperature shows that the state of the battery temperature is relatively stable, so when the average value of the temperature measured for the second number of consecutive times is outside one or more temperature control limits, it is determined that the battery is deformed, wherein the second number is less than the first number, thereby increasing the robustness of the battery thermal management. For another example, when the second threshold value is less than the upper temperature control limit value, it means that the statistical data of the battery temperature show that the state of the battery temperature is unstable. Therefore, the ratio between the temperature control limits in two longer time periods is used to determine whether the battery is deformed, thereby increasing the robustness of the battery thermal management.

[0066] Figure 8A block diagram of a battery thermal management system 800 according to an embodiment of the present disclosure is shown. The battery thermal management system 800 may include: a plurality of temperature sensors 805 for measuring battery temperature; and a control unit 810. In some embodiments, the control unit 810 may be configured to execute the method 400 for battery thermal management. For example, the control unit 810 may be configured to: obtain historical measurement data of battery temperature measured by a plurality of temperature sensors over a period of time; determine statistical data of battery temperature based on the historical measurement data; and determine one or more temperature control limits for battery thermal management based on the statistical data of battery temperature. In some embodiments, the control unit 810 may be integrated into the control system of the vehicle, or a real-time monitoring system (RTM). In some other embodiments, the control unit 810 may be an independent control unit.

[0067] Fig. 9 A block diagram of a vehicle 900 including a battery thermal management system 800 according to an embodiment of the present disclosure is illustrated.

[0068] The "range" disclosed herein is defined in the form of a lower limit and an upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of the particular range. The range defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a range. In this application, unless otherwise specified, the numerical range "ab" represents an abbreviation of any real number combination between a and b, where a and b are both real numbers.

[0069] In this application, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined with each other to form a new technical solution.

[0070] In the present application, unless otherwise specified, all technical features and preferred features mentioned herein can be combined with each other to form new technical solutions. Although the present application has been described with reference to optional embodiments, various improvements can be made thereto and components thereof can be replaced with equivalents without departing from the scope of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any manner. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery thermal management method, comprising: Get historical battery temperature measurements over a period of time; determining statistical data of the battery temperature based on the historical measurement data; as well as One or more temperature control limits for battery thermal management are determined based on the battery temperature statistics.

2. The battery thermal management method according to claim 1, characterized in that: The battery temperature statistics include: a plurality of temperature average values ​​at a plurality of monitoring times within the period of time, wherein each of the plurality of temperature average values ​​is an average value of battery temperatures respectively measured by a plurality of temperature sensors; and / or A plurality of temperature standard deviations at a plurality of monitoring times within the period of time, wherein each of the plurality of temperature standard deviations is a standard deviation of battery temperature respectively measured by a plurality of temperature sensors.

3. The battery thermal management method according to claim 2, characterized in that: The statistical data of the battery temperature further include: an average value of the multiple temperature average values ​​and an average value of the multiple temperature standard deviations, wherein determining the one or more temperature control limits for battery thermal management further includes: taking the average value of the multiple temperature average values ​​as the central reference, determining the one or more temperature control limits based on the statistical probability of abnormal battery temperature fluctuations.

4. The battery thermal management method according to claim 2, characterized in that: The statistical data of the battery temperature include: an average value of the multiple temperature standard deviations, wherein determining the one or more temperature control limits for battery thermal management further includes: taking the average value of the multiple temperature standard deviations as a central reference, determining the one or more temperature control limits based on the statistical probability of abnormal battery temperature fluctuations.

5. The battery thermal management method according to claim 1, characterized in that: The method further comprises: When one of the one or more temperature control limits is less than or equal to a first threshold, it is determined that the battery is deformed when a first number of consecutively measured temperature averages are outside the one or more temperature control limits.

6. The battery thermal management method according to claim 5, characterized in that: The method further comprises: When a first threshold value < one of the one or more temperature control limits ≤ a second threshold value, it is determined that the battery is deformed when a second number of consecutive measured temperature averages are outside the one or more temperature control limits, wherein the first number is greater than the second number.

7. The battery thermal management method according to claim 6, characterized in that: The method further comprises: When the second threshold value is less than one of the one or more temperature control limits, it is determined that the battery is deformed when the third threshold value is less than the ratio between the first temperature control limit and the second temperature control limit, wherein the first temperature control limit is determined based on multiple temperature averages within a recent first period of time, and the second temperature control limit is determined based on multiple temperature averages within a recent second period of time, and the first period of time is longer than the second period of time.

8. A battery thermal management system, comprising: Multiple temperature sensors for measuring battery temperature; as well as A control unit, the control unit being configured to: Acquire historical measurement data of battery temperature measured by the multiple temperature sensors over a period of time; determining statistical data of the battery temperature based on the historical measurement data; as well as One or more temperature control limits for battery thermal management are determined based on the battery temperature statistics.

9. The battery thermal management system according to claim 8, characterized in that: The plurality of temperature sensors are evenly distributed on each module of the battery.

10. The battery thermal management system according to claim 8, characterized in that: The battery temperature statistics include: a plurality of temperature average values ​​at a plurality of monitoring times within the period of time, wherein each of the plurality of temperature average values ​​is an average value of battery temperatures respectively measured by a plurality of temperature sensors; and / or A plurality of temperature standard deviations at a plurality of monitoring times within the period of time, wherein each of the plurality of temperature standard deviations is a standard deviation of battery temperature respectively measured by a plurality of temperature sensors.

11. The battery thermal management system according to claim 10, characterized in that: The statistical data of the battery temperature further include: an average value of the multiple temperature average values ​​and an average value of the multiple temperature standard deviations, wherein determining the one or more temperature control limits for battery thermal management further includes: taking the average value of the multiple temperature average values ​​as the central reference, determining the one or more temperature control limits based on the statistical probability of abnormal battery temperature fluctuations.

12. The battery thermal management system according to claim 10, characterized in that: The statistical data of the battery temperature include: an average value of the multiple temperature standard deviations, wherein determining the one or more temperature control limits for battery thermal management further includes: taking the average value of the multiple temperature standard deviations as a central reference, determining the one or more temperature control limits based on the statistical probability of abnormal battery temperature fluctuations.

13. The battery thermal management system according to claim 8, characterized in that: The control unit is further configured to: When one of the one or more temperature control limits is less than or equal to a first threshold, determining that the battery is deformed when a first number of consecutively measured temperature averages are outside the one or more temperature control limits; or When a first threshold value < one of the one or more temperature control limits ≤ a second threshold value, it is determined that the battery is deformed when a second number of consecutive measured temperature averages are outside the one or more temperature control limits, wherein the first number is greater than the second number.

14. The battery thermal management system according to claim 13, characterized in that: The control unit is further configured to: When the second threshold value is less than one of the one or more temperature control limits, it is determined that the battery is deformed when the third threshold value is less than the ratio between the first temperature control limit and the second temperature control limit, wherein the first temperature control limit is determined based on multiple temperature averages within a recent first period of time, and the second temperature control limit is determined based on multiple temperature averages within a recent second period of time, and the first period of time is longer than the second period of time.

15. A vehicle, comprising: Battery; as well as A battery thermal management system as claimed in any one of claims 8 to 14.

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