A battery pack temperature compensation method and device

Abstract

The application provides a battery pack temperature compensation method and device. The method comprises collecting monitoring temperature values of all temperature monitoring points of a battery pack and extracting a total positive monitoring temperature value, a total negative monitoring temperature value and an innermost temperature value of the battery pack respectively; a difference between the total positive monitoring temperature value and the innermost temperature value of the battery pack is taken as a first monitoring temperature difference; a difference between the total negative monitoring temperature value and the innermost temperature value of the battery pack is taken as a second monitoring temperature difference; when the first monitoring temperature difference and the second monitoring temperature difference are both not greater than a first preset temperature difference threshold, the innermost temperature value of the battery pack is taken as a total positive reporting temperature value and a total negative reporting temperature value of a current reporting period respectively. The method can avoid misjudging normal contact resistance heating as sensor failure, and make the monitoring temperature values of all temperature monitoring points of the battery pack reflect the uniformity with the core of the battery core, so as to facilitate the battery management system to make more accurate estimation of the state of charge and / or the state of health of the battery pack.

Description

Technical Field

[0001] This application relates to the field of new energy battery management system technology, specifically to a battery pack temperature compensation method and device. Background Technology

[0002] In battery pack design, the main positive terminal and the main negative terminal are usually connected to conductive busbars such as copper or aluminum busbars. Due to the potential difference between the main positive terminal and the main negative terminal and the conductive busbar, as well as the difference in the coefficients of thermal expansion of different materials, contact resistance may occur at the connection points after long-term use due to loosening, oxidation, or other reasons.

[0003] When a large current passes through this connection point, significant Joule heating is generated due to the contact resistance. This results in the temperature values ​​collected by the total positive NTC sensor and the total negative NTC sensor being much higher than the temperatures of other cells or modules inside the battery pack.

[0004] In existing technologies, BMS typically struggles to distinguish between "real high temperatures caused by contact resistance" and "data anomalies caused by sensor malfunctions." Reporting the high temperature directly could trigger system overheating, power descent, or even shutdown; while discarding data due to sensor malfunction would prevent monitoring the true thermal state of the terminals. Summary of the Invention

[0005] This application addresses the problems existing in the prior art by providing a battery pack temperature compensation method and device. It can clearly identify whether there is significant heat generation at the connection points between the main positive terminal and the busbar, and between the main negative terminal and the busbar, avoiding misjudging normal contact resistance heating as sensor failure. Furthermore, when the Joule heating effect is not significant, it compensates both the main positive and main negative reported temperature values ​​to the highest temperature value inside the pack, so that the monitored temperature values ​​of all temperature monitoring points in the battery pack reflect the temperature uniformity centered on the battery cell body. This facilitates the battery management system to make more accurate estimates of the battery pack's state of charge and / or health status.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows: In a first aspect, embodiments of this application propose a battery pack temperature compensation method, comprising: collecting the monitoring temperature values ​​of all temperature monitoring points of the battery pack; Based on the monitored temperature values, the total positive monitored temperature value, the total negative monitored temperature value, and the highest temperature value inside the pack are extracted respectively. The total positive monitored temperature value represents the temperature monitored at the total positive electrode temperature monitoring point of the battery pack, the total negative monitored temperature value represents the temperature monitored at the total negative electrode temperature monitoring point of the battery pack, and the highest temperature value inside the pack is the highest monitored temperature value of other temperature monitoring points in the battery pack other than the total positive electrode temperature monitoring point and the total negative electrode temperature monitoring point. The difference between the total positive temperature value and the highest temperature value inside the package is taken as the first monitoring temperature difference; The difference between the total negative monitoring temperature value and the highest temperature value inside the package is taken as the second monitoring temperature difference; Determine whether both the first monitoring temperature difference and the second monitoring temperature difference are not greater than the first preset temperature difference threshold. When both the first monitoring temperature difference and the second monitoring temperature difference are not greater than the first preset temperature difference threshold, the highest temperature value in the package is used as the total positive reported temperature value and the total negative reported temperature value for the current reporting period, respectively.

[0007] In some embodiments, when the first monitored temperature difference is greater than the first preset temperature difference threshold, a flexible approximation reporting method is used to obtain the total positive reported temperature of the current reporting period; and / or when the second monitored temperature difference is greater than the first preset temperature difference threshold, a flexible approximation reporting method is used to obtain the total negative reported temperature of the current reporting period. The total positive reported temperature for the current reporting period is obtained by using flexible approximation reporting, including: The highest temperature value inside the package is used as the initial temperature value for the total positive reporting in the current reporting cycle. The total positive monitored temperature value will be used as the total positive reporting approximation temperature value for the current reporting period; Within the current reporting cycle, the total positive reported temperature gradually changes from the initial total positive reported temperature value to the total positive reported approximate temperature value; The total negative reported temperature for the current reporting period is obtained using a flexible approximation reporting method, including: The highest temperature value inside the package is used as the initial temperature value for the total negative reporting in the current reporting cycle. The total positive monitored temperature value will be used as the total negative reported approximation temperature value for the current reporting cycle. Within the current reporting cycle, the total negative reported temperature gradually changes from the initial total negative reported temperature value to the total negative reported approximate temperature value.

[0008] In some embodiments, the current reporting cycle includes at least two reporting moments; Within the current reporting cycle, the total positive reported temperature value gradually changes from the initial total positive reported temperature value to the total positive reported approximate temperature value, including: Obtain the stepped temperature increment, which represents the reported temperature increment between two adjacent reporting times. The first step jump number is obtained based on the ratio of the first monitoring temperature difference to the step temperature increment. The first step jump number represents the total number of step jumps in the total positive reported temperature value from the initial total positive reported temperature value to the total positive reported temperature value within the current reporting period. The first-step jump reporting stage is obtained by dividing the current reporting period based on the first-step jump variable number; The initial positive temperature value is taken as the total positive temperature value at the first reporting moment of the first step jump reporting phase. The total positive reported temperature value is obtained at each reporting time during the first step jump reporting phase based on the total positive reported initial temperature value and the step temperature increment.

[0009] In some embodiments, the total positive reported temperature value gradually changes from the initial total positive reported temperature value to the total positive reported approximate temperature value within the current reporting cycle, further including: Get the total number of reporting times in the current reporting period; Obtain the first reporting time count, which represents the number of reporting times in the first step jump reporting phase; Determine whether the number of first reported times is less than the total number of reported times; When the number of first reporting moments is less than the total number of reporting moments, the first reporting moment of the current reporting cycle is taken as the first reporting moment of the first step transition reporting stage, and the stage after the first step transition reporting stage in the current reporting cycle is taken as the first fault temperature value reporting stage. The total positive reported approximation temperature value is used as the total positive reported temperature value at each reporting time during the first fault temperature reporting phase.

[0010] In some embodiments, the current reporting cycle includes at least two reporting moments; Within the current reporting cycle, the total negative reported temperature value gradually changes from the initial total negative reported temperature value to the total negative reported approximate temperature value, including: Obtain the stepped temperature increment, which represents the reported temperature increment between two adjacent reporting times. The second step jump number is obtained based on the ratio of the second monitoring temperature difference to the step temperature increment. The second step jump number represents the total number of step jumps in the total negative reported temperature value from the initial total negative reported temperature value to the total negative reported temperature value within the current reporting period. The second-level jump reporting stage is obtained by dividing the current reporting period based on the second-level jump variable number; The initial total negative reported temperature value is used as the total negative reported temperature value at the first reporting moment of the second-step jump reporting phase. The total negative reported temperature value is obtained at each reporting time during the second step jump reporting phase based on the initial total negative reported temperature value and the step temperature increment.

[0011] In some embodiments, the total negative reported temperature value gradually changes from the initial total negative reported temperature value to the total negative reported approximation temperature value within the current reporting cycle, further including: Get the total number of reporting times in the current reporting period; Obtain the second reporting time count, which represents the number of reporting times in the second-step jump reporting phase; Determine whether the number of second reported times is less than the total number of reported times; When the number of second reporting moments is less than the total number of reporting moments, the first reporting moment of the current reporting cycle is taken as the first reporting moment of the second step transition reporting stage, and the stage after the second step transition reporting stage in the current reporting cycle is taken as the second fault temperature value reporting stage. The total negative reported approximation temperature value is used as the total negative reported temperature value in the second fault temperature reporting stage.

[0012] In some embodiments, when the first monitored temperature difference is greater than the first preset temperature difference threshold, a total positive electrode conduction bus fault code for the current reporting period is generated; and / or, when the second monitored temperature difference is greater than the first preset temperature difference threshold, a total negative electrode conduction bus fault code for the current reporting period is generated.

[0013] In some embodiments, the battery pack temperature compensation method further includes: determining whether the battery cells of the battery pack are within a safe operating temperature range based on the monitored temperature value; When the battery cell is in the safe operating temperature range, the difference between the total positive monitoring temperature value and the highest temperature value inside the pack is taken as the first monitoring temperature difference, and the difference between the total negative monitoring temperature value and the highest temperature value inside the pack is taken as the second monitoring temperature difference. It is also determined whether the first monitoring temperature difference and the second monitoring temperature difference are both not greater than the first preset temperature difference threshold.

[0014] In some embodiments, when the battery cell is not in the safe operating temperature range, the total positive monitoring temperature value is used as the total positive reporting temperature value for the current reporting cycle, and the total negative monitoring temperature value is used as the total negative reporting temperature value for the current reporting cycle.

[0015] Secondly, this application also proposes a battery pack temperature compensation device, including a battery pack, a temperature acquisition device, and a battery management system; the battery pack includes multiple temperature monitoring points, including a total positive electrode temperature monitoring point and a total negative electrode temperature monitoring point, the acquisition end of the temperature acquisition device is connected to each temperature monitoring point, and the battery management system is connected to the temperature acquisition device. The temperature acquisition device is used to collect the monitoring temperature values ​​of all temperature monitoring points of the battery pack; The battery management system is used to extract the total positive monitoring temperature value, the total negative monitoring temperature value, and the highest temperature value inside the battery pack based on the monitored temperature value. The difference between the total positive monitoring temperature value and the highest temperature value inside the battery pack is used as the first monitoring temperature difference, and the difference between the total negative monitoring temperature value and the highest temperature value inside the battery pack is used as the second monitoring temperature difference. It is determined whether the first monitoring temperature difference and the second monitoring temperature difference are both not greater than a first preset temperature difference threshold. When the first monitoring temperature difference and the second monitoring temperature difference are both not greater than the first preset temperature difference threshold, the highest temperature value inside the battery pack is used as the total positive reported temperature value and the total negative reported temperature value of the current reporting period, respectively. The total positive monitoring temperature value represents the temperature monitoring value of the total positive electrode temperature monitoring point of the battery pack, the total negative monitoring temperature value represents the temperature monitoring value of the total negative electrode temperature monitoring point of the battery pack, and the highest temperature value inside the pack is the highest monitoring temperature value of other temperature monitoring points in the battery pack other than the total positive electrode temperature monitoring point and the total negative electrode temperature monitoring point. The battery management system is also used to perform the reporting of total positive and total negative temperature values.

[0016] Compared with the prior art, this application has the following advantages: This application compares the first and second monitored temperature differences with the first preset temperature difference threshold, which can clearly identify whether there is significant heat generation at the connection points between the positive terminal and the busbar, and between the negative terminal and the busbar. This avoids misjudging normal contact resistance heating as a sensor malfunction. Furthermore, when the Joule heating effect is not significant, both the total positive and total negative reported temperature values ​​are compensated to the highest temperature value inside the pack. This ensures that the monitored temperature values ​​at all temperature monitoring points in the battery pack reflect the temperature uniformity centered on the battery cell body, facilitating a more accurate estimation of the battery pack's state of charge and / or health status by the battery management system. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the battery pack temperature compensation method in an embodiment of this application. Figure 2 This is a schematic diagram illustrating the logical relationship between whether battery pack temperature compensation is performed in the embodiments of this application; Figure 3 This is a schematic diagram showing the connection relationship of the battery pack temperature compensation device in the embodiments of this application. Detailed Implementation

[0018] To clearly illustrate the technical features of this solution, the implementation methods of this application will be described in detail below with reference to the accompanying drawings and embodiments. This will allow for a full understanding and implementation of how this application uses technical means to solve technical problems and achieve corresponding technical effects. The embodiments of this application and the various features within them can be combined with each other without conflict, and the resulting technical solutions are all within the protection scope of this application.

[0019] In a first aspect, embodiments of this application propose a battery pack temperature compensation method, comprising: collecting the monitored temperature values ​​of all temperature monitoring points of the battery pack; see also Figure 2The system determines whether the battery cells in the battery pack are within the safe operating temperature range based on monitored temperature values. The safe operating temperature range characterizes the temperature range within which the battery pack operates normally and safely. This range is determined jointly based on the battery pack's material electrochemical characteristics, national and mandatory standards, battery management and protection strategies, thermal runaway boundaries, and operating condition verification. Optionally, the safe operating temperature range is [-30℃, 45℃]. Optionally, determining whether the battery cells in the battery pack are within the safe operating temperature range based on monitored temperature values ​​includes: The highest monitored temperature value will be taken as the highest temperature value of the battery cell. Determine whether the highest temperature value of the battery cell is within the safe operating temperature range; When the highest temperature of the battery cell is within the safe operating temperature range, the battery cell is within the safe operating temperature range. When the highest temperature of the battery cell is not within the safe operating temperature range, the battery cell is not within the safe operating temperature range.

[0020] In some embodiments, when the battery cell is not within the safe operating temperature range, the total positive monitoring temperature value is used as the total positive reported temperature value for the current reporting period, and the total negative monitoring temperature value is used as the total negative reported temperature value for the current reporting period. At this time, no temperature compensation operation is performed, and the total positive monitoring temperature value and the total negative monitoring temperature value are reported directly and truthfully. The total positive monitoring temperature value represents the temperature monitoring value of the total positive electrode temperature sampling monitoring point of the battery pack, the total negative monitoring temperature value represents the temperature monitoring value of the total negative electrode temperature sampling monitoring point of the battery pack, the total positive reported temperature value represents the temperature reported value of the total positive electrode temperature sampling monitoring point of the battery pack, and the total negative reported temperature value represents the temperature reported value of the total negative electrode temperature sampling monitoring point of the battery pack.

[0021] See Figure 1 When the battery cell is in the safe operating temperature range, the total positive monitoring temperature value, the total negative monitoring temperature value, and the highest temperature value inside the pack are extracted based on the monitored temperature value. The highest temperature value inside the pack is the highest value of the monitored temperature values ​​of other temperature monitoring points in the battery pack, excluding the total positive electrode temperature monitoring point and the total negative electrode temperature monitoring point. The difference between the total positive temperature value and the highest temperature value inside the package is taken as the first monitoring temperature difference; The difference between the total negative monitoring temperature value and the highest temperature value inside the package is taken as the second monitoring temperature difference; Determine whether both the first and second monitored temperature differences are not greater than a first preset temperature difference threshold. The first preset temperature difference threshold represents the maximum monitored temperature difference at which the contact resistance at the connection between the terminal and the busbar does not exhibit a Joule heating effect. In other words, a monitored temperature difference not exceeding the first preset temperature difference threshold indicates that the Joule heating effect generated by the contact resistance at the connection between the terminal and the busbar is not significant. The terminal includes the total positive terminal and the total negative terminal, and the corresponding monitored temperature differences include the first and second monitored temperature differences. Optionally, the range of the first preset temperature difference threshold includes 3... ~8 Typically, the first preset temperature difference threshold is set to 5. ; When both the first monitoring temperature difference and the second monitoring temperature difference are not greater than the first preset temperature difference threshold, the highest temperature value in the package is used as the total positive reported temperature value and the total negative reported temperature value for the current reporting period, respectively.

[0022] By comparing the first and second monitored temperature differences with the first preset temperature difference threshold, it is possible to clearly identify whether there is significant heating at the connection points between the positive terminal and the busbar, and between the negative terminal and the busbar. This avoids misjudging normal contact resistance heating as a sensor malfunction. Furthermore, when the Joule heating effect is not significant, both the total positive and negative reported temperature values ​​are compensated to the highest temperature value within the battery pack. This ensures that the monitored temperature values ​​at all temperature monitoring points in the battery pack reflect the temperature uniformity centered on the battery cell body, facilitating a more accurate estimation of the battery pack's state of charge and / or health status by the battery management system.

[0023] In some embodiments, when the first monitored temperature difference is greater than a first preset temperature difference threshold, a flexible approximation reporting method is used to obtain the total positive reported temperature value for the current reporting period. At this time, the connection between the total positive terminal and the busbar is abnormal. And / or when the second monitored temperature difference is greater than the first preset temperature difference threshold, a flexible approximation reporting method is used to obtain the total negative reported temperature value for the current reporting period. At this time, the connection between the total negative terminal and the busbar is abnormal. Flexible approximation reporting characterizes the reporting of progressive physical quantities.

[0024] The total positive reported temperature value for the current reporting period is obtained by using flexible approximation reporting, including: taking the highest temperature value in the package as the initial total positive reported temperature value for the current reporting period; taking the total positive monitored temperature value as the approximate total positive reported temperature value for the current reporting period; and gradually changing the total positive reported temperature value from the initial total positive reported temperature value to the approximate total positive reported temperature value within the current reporting period. The total negative reported temperature value for the current reporting period is obtained by using flexible approximation reporting, including: taking the highest temperature value in the package as the initial total negative reported temperature value for the current reporting period; taking the total positive monitored temperature value as the approximate total negative reported temperature value for the current reporting period; and gradually changing the total negative reported temperature value from the initial total negative reported temperature value to the approximate total negative reported temperature value within the current reporting period.

[0025] Using flexible approximation reporting can reflect the high temperature trend of the connection between the terminal and the busbar where the connection abnormality occurred to the system, while avoiding overly aggressive power reduction protection caused by sudden temperature changes, thus preserving a processing window for the system.

[0026] In some embodiments, the current reporting period includes at least two reporting moments; typically, the current reporting period is 1 minute, and the total number of reporting moments ranges from [2, 60] using different jump frequencies. Within the current reporting cycle, the total positive reported temperature value gradually changes from the initial total positive reported temperature value to the total positive reported approximate temperature value, including: Obtain the stepped temperature increment, which represents the reported temperature increment between two adjacent reporting times. Optionally, the stepped temperature increment is set to 1. ; The first step jump number is obtained based on the ratio of the first monitored temperature difference to the step temperature increment. The first step jump number represents the total number of step jumps in the total positive reported temperature value within the current reporting period, from the initial total positive reported temperature value to the total positive reported approximate temperature value. For example, the step temperature increment is 1. The total positive temperature reported in the current reporting cycle is 25. Jump to 26 Based on the step temperature increment, there was one step jump, and the first step jump number was 1; The first step jump reporting stage is obtained by dividing the current reporting period based on the first step jump number. Optionally, the first step jump reporting stage is obtained by dividing the front part of the current reporting period based on the first step jump number. The division of the front part of the current reporting period is characterized by starting from the first reporting time in the current reporting period. When the first step jump number is 1, the division starts from the first reporting time in the current reporting period. A step jump has occurred. Then the first step jump reporting stage includes the first two reporting times in the current reporting period. The initial positive temperature value is taken as the total positive temperature value at the first reporting moment of the first step jump reporting stage. The first reporting moment of the first step jump reporting stage is the first reporting moment of the first step jump reporting stage. The total positive reported temperature value is obtained by progressively increasing the initial positive reported temperature value and the step temperature increment in the first step jump reporting stage. That is, in the first step jump reporting stage, the total positive reported temperature value at the current reporting time is obtained by adding the step temperature increment to the total positive reported temperature value at the previous reporting time.

[0027] For example, the highest temperature inside the bag is 25 degrees Celsius. The total positive temperature value is 31. The first preset temperature difference threshold is 5. At this time, the first monitored temperature difference is... If the temperature difference exceeds the first preset threshold, the step temperature increment is 1. The first-step jump number is 6, meaning that within the current reporting cycle, 7 consecutive reporting times are selected as the first-step jump reporting phase. Optionally, reporting times 1 to 7 can be selected as the first-step jump reporting phase, and the total positive initial temperature value, i.e., the highest temperature value inside the package, 25, will be reported. As the total positive reported temperature value at the first reporting moment of the first-step transition reporting phase, the total positive reported temperature value of the first-step transition reporting phase, sorted by the 1st to 7th reporting moments, is as follows: 25 26 27 28 29 30 、 and 31 .

[0028] Similarly, within the current reporting cycle, the total negative reported temperature value gradually changes from the initial total negative reported temperature value to the total negative reported approximate temperature value, including: Obtain the stepped temperature increment, which represents the reported temperature increment between two adjacent reporting times. The second step jump number is obtained based on the ratio of the second monitoring temperature difference to the step temperature increment. The second step jump number represents the total number of step jumps in the total negative reported temperature value from the initial total negative reported temperature value to the total negative reported temperature value within the current reporting period. The second-step jump reporting stage is obtained by dividing the first part of the current reporting cycle based on the second-step jump variable. The initial total negative reported temperature value is used as the total negative reported temperature value at the first reporting moment of the second-step jump reporting phase. The total negative reported temperature value is obtained at each reporting time during the second step jump reporting phase based on the initial total negative reported temperature value and the step temperature increment.

[0029] In some embodiments, the total positive reported temperature value gradually changes from the initial total positive reported temperature value to the total positive reported approximate temperature value within the current reporting cycle, further including: Get the total number of reporting times in the current reporting period; Obtain the first reporting time count, which represents the number of reporting times in the first step jump reporting phase; Determine whether the number of first reported times is less than the total number of reported times; When the number of first reporting moments is less than the total number of reporting moments, the first reporting moment of the current reporting cycle is taken as the first reporting moment of the first step transition reporting stage, and the stage after the first step transition reporting stage in the current reporting cycle is taken as the first fault temperature value reporting stage. The total positive reported approximation temperature value is used as the total positive reported temperature value at each reporting time during the first fault temperature reporting phase.

[0030] The highest temperature inside the bag is still set at 25 degrees Celsius. The total positive temperature value is 31. The first preset temperature difference threshold is 5. The step temperature increment is 1. For example, the current reporting cycle is 1 minute, and the total number of reporting times is 10. At this time, the first reporting time is 7. The 1st to 7th reporting times are selected as the first step transition reporting stage. The stages following the first step transition reporting stage, namely the 8th, 9th, and 10th reporting times, are the first fault temperature value reporting stage. Therefore, the total positive reported temperature values ​​in the first fault temperature value reporting stage, sorted by the 8th to 10th reporting times, are 31. 31 、 and 31 That is, the total positive reported temperature values ​​for the current reporting period, sorted by the 1st to 10th reporting times, are as follows: 25 26 27 28 29 30 31 31 31 、 and 31 .

[0031] Similarly, within the current reporting cycle, the total negative reported temperature value gradually changes from the initial total negative reported temperature value to the total negative reported approximate temperature value, which also includes: Get the total number of reporting times in the current reporting period; Obtain the second reporting time count, which represents the number of reporting times in the second-step jump reporting phase; Determine whether the number of second reported times is less than the total number of reported times; When the number of second reporting moments is less than the total number of reporting moments, the first reporting moment of the current reporting cycle is taken as the first reporting moment of the second step transition reporting stage, and the stage after the second step transition reporting stage in the current reporting cycle is taken as the second fault temperature value reporting stage. The total negative reported approximation temperature value is used as the total negative reported temperature value in the second fault temperature reporting stage.

[0032] In some embodiments, the total number of reporting times includes a first total number of reporting times and a second total number of reporting times. The second total number of reporting times is greater than the first total number of reporting times. That is, the switching frequency of the current reporting cycle is preset. Different switching frequencies are selected according to the severity of the Joule heating effect of the contact resistance at the connection between the terminal and the busbar. The severity of the Joule heating effect of the contact resistance is quantified and can be reflected intuitively by the switching frequency. Get the total number of reporting moments in the current reporting period, including: A second preset temperature difference threshold is obtained. This threshold represents the maximum monitored temperature difference at which the contact resistance at the connection point between the terminal and the busbar exhibits a Joule heating effect and the degree of connection abnormality is highly controllable. In other words, a monitored temperature difference not exceeding the second preset temperature difference threshold indicates that the Joule heating effect generated by the contact resistance at the connection point between the terminal and the busbar is significant but of low significance; a monitored temperature difference exceeding the second preset temperature difference threshold indicates that the Joule heating effect generated by the contact resistance at the connection point between the terminal and the busbar is significant and of high significance. Optionally, the range of the second preset temperature difference threshold includes 5... ~12 Typically, the first preset temperature difference threshold is set to 10. .

[0033] Determine whether the first monitored temperature difference and / or the second monitored temperature difference is not greater than the second preset temperature difference threshold; When the first monitoring temperature difference and / or the second monitoring temperature difference is not greater than the second preset temperature difference threshold, the total number of the first reporting time is taken as the total number of reporting time in the current reporting cycle.

[0034] When the first monitoring temperature difference and / or the second monitoring temperature difference are greater than the second preset temperature difference threshold, the total number of the second reporting time is taken as the total number of reporting time in the current reporting cycle.

[0035] Optionally, the total number of the first reporting time can range from 5 to 12, and the total number of the second reporting time can range from 10 to 20. Typically, the total number of the first reporting time is 10, and the total number of the second reporting time is 20.

[0036] In some embodiments, when the first monitored temperature difference is greater than the first preset temperature difference threshold, a total positive busbar fault code for the current reporting period is generated. The total positive busbar fault code indicates a connection abnormality fault caused by the Joule heating effect generated by the contact resistance of the connection between the total positive terminal and the busbar. And / or, when the second monitored temperature difference is greater than the first preset temperature difference threshold, a total negative busbar fault code for the current reporting period is generated. The total negative busbar fault code indicates a connection abnormality fault caused by the Joule heating effect generated by the contact resistance of the connection between the total negative terminal and the busbar.

[0037] See Figure 3 Secondly, this application also proposes a battery pack temperature compensation device, including a battery pack, a temperature acquisition device (e.g., a temperature acquisition sensor) and a battery management system; the battery pack includes multiple temperature monitoring points, including a total positive electrode temperature monitoring point and a total negative electrode temperature monitoring point, the acquisition end of the temperature acquisition device is connected to each temperature monitoring point respectively, and the battery management system is connected to the temperature acquisition device. The temperature acquisition device is used to collect the monitoring temperature values ​​of all temperature monitoring points of the battery pack; The battery management system is used to extract the total positive monitoring temperature value, the total negative monitoring temperature value, and the highest temperature value inside the battery pack based on the monitored temperature value. The difference between the total positive monitoring temperature value and the highest temperature value inside the battery pack is used as the first monitoring temperature difference, and the difference between the total negative monitoring temperature value and the highest temperature value inside the battery pack is used as the second monitoring temperature difference. It is determined whether the first monitoring temperature difference and the second monitoring temperature difference are both not greater than a first preset temperature difference threshold. When the first monitoring temperature difference and the second monitoring temperature difference are both not greater than the first preset temperature difference threshold, the highest temperature value inside the battery pack is used as the total positive reported temperature value and the total negative reported temperature value of the current reporting period, respectively. The total positive monitoring temperature value represents the temperature monitoring value of the total positive electrode temperature monitoring point of the battery pack, the total negative monitoring temperature value represents the temperature monitoring value of the total negative electrode temperature monitoring point of the battery pack, and the highest temperature value inside the pack is the highest monitoring temperature value of other temperature monitoring points in the battery pack other than the total positive electrode temperature monitoring point and the total negative electrode temperature monitoring point. The battery management system is also used to perform the reporting of total positive and total negative temperature values.

[0038] Those skilled in the art will understand that embodiments of this application can be provided as methods, apparatus (systems), or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0039] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce an instruction that executes via the processor of the computer or other programmable data processing apparatus to create an instruction for implementing the flowchart. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0040] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0041] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0042] Finally, it should be noted that the above content is only used to illustrate the technical solution of this application, and is not intended to limit the scope of protection of this application. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of this application shall not depart from the substance and scope of the technical solution of this application.

Claims

1. A battery pack temperature compensation method, characterized in that, include: Collect the monitored temperature values ​​from all temperature monitoring points of the battery pack; Based on the monitored temperature values, the total positive monitored temperature value, the total negative monitored temperature value, and the highest temperature value inside the pack are extracted respectively. The total positive monitored temperature value represents the temperature monitoring value of the total positive electrode temperature monitoring point of the battery pack, the total negative monitored temperature value represents the temperature monitoring value of the total negative electrode temperature monitoring point of the battery pack, and the highest temperature value inside the pack is the highest value of the monitored temperature values ​​of the other temperature monitoring points of the battery pack, excluding the total positive electrode temperature monitoring point and the total negative electrode temperature monitoring point. The difference between the total positive monitored temperature value and the highest temperature value inside the package is taken as the first monitored temperature difference; The difference between the total negative monitored temperature value and the highest temperature value inside the package is taken as the second monitored temperature difference; Determine whether both the first monitored temperature difference and the second monitored temperature difference are not greater than the first preset temperature difference threshold. When both the first monitored temperature difference and the second monitored temperature difference are not greater than the first preset temperature difference threshold, the highest temperature value in the package is used as the total positive reported temperature value and the total negative reported temperature value for the current reporting period, respectively.

2. The battery pack temperature compensation method according to claim 1, characterized in that, When the first monitored temperature difference is greater than the first preset temperature difference threshold, the total positive reported temperature value of the current reporting period is obtained by flexible approximation reporting. And / or when the second monitored temperature difference is greater than the first preset temperature difference threshold, the total negative reported temperature value of the current reporting period is obtained by flexible approximation reporting; The total positive reported temperature value for the current reporting period is obtained using flexible approximation reporting, including: The highest temperature value within the package is used as the initial temperature value for the total positive reporting in the current reporting cycle. The total positive monitored temperature value is used as the total positive reporting approximation temperature value for the current reporting period; Within the current reporting period, the total positive reported temperature value gradually changes from the initial total positive reported temperature value to the approximate total positive reported temperature value; The total negative reported temperature value for the current reporting period is obtained using flexible approximation reporting, including: The highest temperature value within the package is used as the initial total negative reporting temperature value for the current reporting cycle. The total positive monitored temperature value is used as the total negative reported approximation temperature value for the current reporting cycle; Within the current reporting period, the total negative reported temperature value gradually changes from the initial total negative reported temperature value to the approximate total negative reported temperature value.

3. The battery pack temperature compensation method according to claim 2, characterized in that, The current reporting cycle includes at least two reporting times; Within the current reporting period, the total positive reported temperature value gradually changes from the initial total positive reported temperature value to the approximate total positive reported temperature value, including: Obtain the stepped temperature increment, which represents the reported temperature increment between two adjacent reporting times. The first step jump number is obtained based on the ratio of the first monitored temperature difference to the step temperature increment. The first step jump number represents the total number of step jumps in the current reporting period, from the initial total positive reported temperature value to the approximate total positive reported temperature value. The first step jump reporting stage is obtained by dividing the current reporting period based on the first step jump number; The total positive reporting initial temperature value is used as the total positive reporting temperature value at the first reporting moment of the first step transition reporting phase; The total positive reported temperature value is obtained at each reporting time within the first step transition reporting phase based on the total positive reported initial temperature value and the step temperature increment.

4. The battery pack temperature compensation method according to claim 3, characterized in that, Within the current reporting period, the total positive reported temperature value gradually changes from the initial total positive reported temperature value to the approximate total positive reported temperature value, further including: Obtain the total number of reporting times in the current reporting period; Obtain the first reporting time count, where the first reporting time count represents the number of reporting times in the first step transition reporting phase; Determine whether the first number of reported times is less than the total number of reported times; When the number of the first reporting time is less than the total number of reporting time, the first reporting time of the current reporting cycle is taken as the first reporting time of the first step transition reporting stage, and the stage in the current reporting cycle that is after the first step transition reporting stage is taken as the first fault temperature value reporting stage. The total positive reported approximation temperature value is used as the total positive reported temperature value at each reporting time during the first fault temperature reporting phase.

5. The battery pack temperature compensation method according to claim 2, characterized in that, The current reporting cycle includes at least two reporting times; Within the current reporting period, the total negative reported temperature value gradually changes from the initial total negative reported temperature value to the approximate total negative reported temperature value, including: Obtain the stepped temperature increment, which represents the reported temperature increment between two adjacent reporting times. The second step jump number is obtained based on the ratio of the second monitored temperature difference to the step temperature increment. The second step jump number represents the total number of step jumps in the internal temperature and the total negative reported temperature value from the initial total negative reported temperature value to the total negative reported approximate temperature value. The second-step jump reporting stage is obtained by dividing the current reporting period based on the second-step jump number; The total negative reporting initial temperature value is used as the total negative reporting temperature value at the first reporting moment of the second step jump reporting phase; The total negative reported temperature value is obtained at each reporting time during the second step transition reporting phase based on the initial total negative reported temperature value and the step temperature increment.

6. The battery pack temperature compensation method according to claim 5, characterized in that, Within the current reporting period, the total negative reported temperature value gradually changes from the initial total negative reported temperature value to the approximate total negative reported temperature value, further including: Obtain the total number of reporting times in the current reporting period; Obtain the second reporting time count, which represents the number of reporting times in the second step transition reporting phase; Determine whether the second number of reported times is less than the total number of reported times; When the number of the second reporting time is less than the total number of reporting time, the first reporting time of the current reporting cycle is taken as the first reporting time of the second step transition reporting stage, and the stage in the current reporting cycle that is after the second step transition reporting stage is taken as the second fault temperature value reporting stage. The total negative reporting approximation temperature value is used as the total negative reporting temperature value in the second fault temperature reporting stage.

7. The battery pack temperature compensation method according to claim 2, characterized in that, When the first monitored temperature difference is greater than the first preset temperature difference threshold, a total positive electrode conduction fault code for the current reporting period is generated; and / or, when the second monitored temperature difference is greater than the first preset temperature difference threshold, a total negative electrode conduction fault code for the current reporting period is generated.

8. The battery pack temperature compensation method according to claim 1, characterized in that, The battery pack temperature compensation method further includes: determining whether the battery cells of the battery pack are within the safe operating temperature range based on the monitored temperature value; When the battery cell is in the safe operating temperature range, the difference between the total positive monitoring temperature value and the highest temperature value inside the package is taken as the first monitoring temperature difference, and the difference between the total negative monitoring temperature value and the highest temperature value inside the package is taken as the second monitoring temperature difference. It is also determined whether the first monitoring temperature difference and the second monitoring temperature difference are both not greater than the first preset temperature difference threshold.

9. The battery pack temperature compensation method according to claim 8, characterized in that, When the battery cell is not within the safe operating temperature range, the total positive monitoring temperature value is used as the total positive reporting temperature value for the current reporting period, and the total negative monitoring temperature value is used as the total negative reporting temperature value for the current reporting period.

10. A battery pack temperature compensation device, characterized in that, The system includes a battery pack, a temperature acquisition device, and a battery management system. The battery pack includes multiple temperature monitoring points, including a total positive electrode temperature monitoring point and a total negative electrode temperature monitoring point. The acquisition terminal of the temperature acquisition device is connected to each of the temperature monitoring points. The battery management system is connected to the temperature acquisition device. The temperature acquisition device is used to collect the monitoring temperature values ​​of all the temperature monitoring points of the battery pack; The battery management system is used to extract the total positive monitoring temperature value, the total negative monitoring temperature value, and the highest temperature value inside the pack based on the monitored temperature value. The difference between the total positive monitoring temperature value and the highest temperature value inside the pack is used as the first monitoring temperature difference, and the difference between the total negative monitoring temperature value and the highest temperature value inside the pack is used as the second monitoring temperature difference. The system determines whether the first monitoring temperature difference and the second monitoring temperature difference are both not greater than a first preset temperature difference threshold. When the first monitoring temperature difference and the second monitoring temperature difference are both not greater than the first preset temperature difference threshold, the highest temperature value inside the pack is used as the total positive reported temperature value and the total negative reported temperature value for the current reporting period. The total positive monitoring temperature value represents the temperature monitoring value of the total positive electrode temperature monitoring point of the battery pack, the total negative monitoring temperature value represents the temperature monitoring value of the total negative electrode temperature monitoring point of the battery pack, and the highest temperature value inside the pack is the highest value of the monitoring temperature values ​​of the other temperature monitoring points of the battery pack, excluding the total positive electrode temperature monitoring point and the total negative electrode temperature monitoring point. The battery management system is also used to perform the reporting of the total positive reported temperature value and the total negative reported temperature value.

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