Battery temperature analysis method and equipment

Abstract

The invention provides a battery temperature analysis method and equipment. The battery temperature analysis method comprises the following steps: acquiring battery temperatures corresponding to a plurality of temperature acquisition points in a battery module in a detection period; acquiring the average battery temperature and the lowest battery temperature corresponding to the plurality of temperature acquisition points; and under the condition that the temperature difference is smaller than a preset temperature threshold value, it is determined that the battery temperatures corresponding to the multiple temperature collection point positions are normal, and the temperature difference is the difference between the average battery temperature and the lowest battery temperature. The battery temperature abnormal value is screened by adopting the battery average temperature and the preset temperature threshold value, so that whether the temperature abnormal value is valid data or false alarm is identified, and the accuracy of the temperature data is guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of temperature monitoring, and in particular to a battery temperature analysis method and device. Background Art

[0002] Battery temperature detection is an important part of the battery management system BMS. It usually uses thermistor temperature sensors to collect battery temperatures at multiple points in the battery module. The battery module management unit BMU reads the data collected by the temperature sensor and uploads the collected data to the battery management system BMS.

[0003] When used in mobile vehicle battery systems, there is a possibility of loose lines and loose connections due to vibration, which may cause the collected temperature data to be distorted and the battery management system BMS strategy decision to erroneously operate, affecting the reliability of the battery system. Summary of the invention

[0004] The object of the present invention is to provide a battery temperature analysis method and device to improve the above-mentioned problem.

[0005] In order to achieve the above purpose, the technical solution adopted by the embodiment of the present invention is as follows:

[0006] In a first aspect, an embodiment of the present invention provides a battery temperature analysis method, the method comprising:

[0007] Obtain the battery temperatures corresponding to multiple temperature collection points in the battery module during the detection cycle;

[0008] Obtain the average battery temperature and the minimum battery temperature corresponding to multiple temperature collection points;

[0009] When the temperature difference is less than a preset temperature threshold, it is determined that the battery temperatures corresponding to the multiple temperature collection points are normal, wherein the temperature difference is the difference between the average battery temperature and the lowest battery temperature.

[0010] Optionally, the battery module includes a plurality of single cells, each of which is provided with at least one temperature collection point, and the method further includes:

[0011] When the temperature difference is greater than or equal to a preset temperature threshold, obtaining electrical property data of each single battery in the battery module within a detection period;

[0012] Combined with the electrical property data of each single battery, confirm whether the battery temperature corresponding to multiple temperature collection points is abnormal.

[0013] Optionally, the electrical property data of the single cell is voltage data of the single cell.

[0014] Optionally, the step of combining the electrical property data of each single battery to determine whether the battery temperatures corresponding to the multiple temperature collection points are abnormal includes:

[0015] Obtain the average voltage change rate of all single cells during the detection cycle;

[0016] Obtaining a target voltage change rate of a target battery within a detection period, wherein the target battery is a single cell corresponding to the lowest battery temperature within the detection period;

[0017] Confirm whether the voltage change rate difference is less than a preset voltage change rate threshold; wherein the voltage change rate difference is an absolute value of a difference between the target voltage change rate and the average voltage change rate;

[0018] If not, it is determined that the battery temperatures corresponding to the multiple temperature collection points are normal.

[0019] Optionally, the step of determining whether the battery temperatures corresponding to the multiple temperature collection points are abnormal in combination with the electrical property data of each single battery further includes:

[0020] If the voltage change rate difference is less than the preset voltage change rate threshold, it is confirmed that the battery temperatures corresponding to the multiple temperature collection points are abnormal.

[0021] Optionally, after confirming that the battery temperatures corresponding to the multiple temperature collection points are abnormal, the method further includes: using the average battery temperature as a corrected temperature value of the target battery.

[0022] In a second aspect, an embodiment of the present invention provides a battery temperature analysis device, the battery temperature analysis device comprising a battery module management unit and a battery management system, the battery management system being connected to the battery module management unit;

[0023] The battery module management unit is used to obtain the battery temperatures corresponding to multiple temperature collection points in the battery module within the detection period, and transmit the obtained battery temperatures to the battery management system;

[0024] The battery management system is used to obtain battery temperatures corresponding to multiple temperature collection points transmitted by the battery module management unit;

[0025] The battery management system is used to obtain the average battery temperature and the minimum battery temperature corresponding to multiple temperature collection points;

[0026] The battery management system is used to determine that the battery temperatures corresponding to the multiple temperature collection points are normal when the difference between the battery average temperature and the battery minimum temperature is less than a preset temperature threshold.

[0027] Optionally, the battery module includes a plurality of single cells, and each single cell is provided with at least one temperature collection point;

[0028] The battery module management unit is used to detect the electrical property data of each single battery in the battery module within a cycle, and transmit the acquired battery temperature and electrical property data to the battery management system;

[0029] The battery management system is used to obtain the electrical property data of each single battery transmitted by the battery module management unit;

[0030] The battery management system is used to combine the electrical property data of each single battery to confirm whether the battery temperature corresponding to multiple temperature collection points is abnormal.

[0031] Optionally, the electrical property data of the single cell is voltage data of the single cell;

[0032] The battery management system is used to obtain the average voltage change rate of all single cells during a detection cycle; obtain the target voltage change rate of a target battery during the detection cycle, wherein the target battery is the single cell corresponding to the lowest battery temperature during the detection cycle; confirm whether the voltage change rate difference is less than a preset voltage change rate threshold; wherein the voltage change rate difference is the absolute value of the difference between the target voltage change rate and the average voltage change rate; if not, determine that the battery temperatures corresponding to multiple temperature collection points are normal; if so, confirm that the battery temperatures corresponding to multiple temperature collection points are abnormal.

[0033] Optionally, after confirming that the battery temperatures corresponding to the multiple temperature collection points are abnormal, the battery management system is used to use the average battery temperature as the corrected temperature value of the target battery.

[0034] Compared with the prior art, the battery temperature analysis method and device provided in the embodiment of the present invention obtains the battery temperature corresponding to multiple temperature collection points in the battery module within the detection period; obtains the battery average temperature and the battery minimum temperature corresponding to multiple temperature collection points; when the temperature difference is less than the preset temperature threshold, determines that the battery temperature corresponding to the multiple temperature collection points is normal, wherein the temperature difference is the difference between the battery average temperature and the battery minimum temperature. The battery average temperature and the preset temperature threshold (also called the temperature redundancy constant) are used to filter the battery temperature abnormal value, so as to identify whether the temperature abnormal value is valid data or a false alarm, thereby ensuring the accuracy of the temperature data.

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 This is one of the structural schematic diagrams of the battery temperature analysis device provided in an embodiment of the present invention.

[0038] Figure 2 The second structural schematic diagram of the battery temperature analysis device provided in an embodiment of the present invention.

[0039] Figure 3 A schematic diagram of a flow chart of a battery temperature analysis method provided in an embodiment of the present invention.

[0040] In the figure: 10 - battery management system; 20 - battery module management unit; 30 - temperature acquisition unit; 40 - voltage acquisition unit. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0042] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0044] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0045] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are directions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0046] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0048] In order to deal with the situation of loose lines and false connections caused by vibration, the embodiments of the present invention provide a battery temperature analysis method and device, which can avoid distortion of collected temperature data, ensure the correctness of the battery management system BMS strategy decision, and improve the reliability of the battery system.

[0049] Please refer to Figure 1 , Figure 1 This is one of the structural schematic diagrams of the battery temperature analysis device provided by the embodiment of the present invention. The battery temperature analysis device includes a battery management system 10 and a battery module management unit 20 , and the battery management system 10 is connected to the battery module management unit 20 .

[0050] The battery management system 10 may be, but is not limited to, a battery management system, or BMS for short. The battery module management unit 20 may be, but is not limited to, a battery management unit, or BMU for short.

[0051] The battery module management unit 20 is used to obtain the battery temperatures corresponding to multiple temperature collection points in the battery module within a detection period, and transmit the obtained battery temperatures to the battery management system 10 .

[0052] The battery module management unit 20 is used to detect the electrical property data of each single battery in the battery module during the cycle, and transmit the acquired battery temperature and electrical property data to the battery management system 10. The electrical property data may be voltage data, current data, and capacity data of the single battery.

[0053] Please refer to Figure 2 , Figure 2 The second structural diagram of the battery temperature analysis device provided by the embodiment of the present invention. The battery temperature analysis device includes a temperature acquisition unit 30 and a voltage acquisition unit 40. The temperature acquisition unit 30 and the voltage acquisition unit 40 are both connected to the battery module management unit 20.

[0054] The temperature acquisition unit 30 is set at the corresponding temperature acquisition point to acquire the battery temperature corresponding to the temperature acquisition point for reading by the battery module management unit 20. The voltage acquisition unit 40 is set at each single cell to acquire the voltage data corresponding to the single cell for reading by the battery module management unit 20.

[0055] Optionally, the temperature acquisition unit 30 may be, but is not limited to, a thermistor temperature sensor to acquire the battery temperature in the battery module at multiple points. The voltage acquisition unit 40 may be, but is not limited to, a voltage sensor.

[0056] The battery management system 10 is used to obtain battery temperatures corresponding to multiple temperature collection points transmitted by the battery module management unit 20 .

[0057] The battery management system 10 is used to obtain the average battery temperature and the minimum battery temperature corresponding to multiple temperature collection points.

[0058] The battery management system 10 is used to determine that the battery temperatures corresponding to the multiple temperature collection points are normal when the difference between the battery average temperature and the battery minimum temperature is less than a preset temperature threshold.

[0059] In an optional embodiment, the battery module includes a plurality of single cells, and each single cell is provided with at least one temperature collection point.

[0060] When the difference between the average battery temperature and the lowest battery temperature is greater than or equal to a preset temperature threshold, the battery management system 10 is used to obtain the electrical property data of each single battery transmitted by the battery module management unit 20 .

[0061] The battery management system 10 is used to determine whether the battery temperatures corresponding to the multiple temperature collection points are abnormal, based on the electrical property data of each single battery.

[0062] Optionally, the electrical property data of the single cell is voltage data of the single cell.

[0063] The battery management system 10 is used to obtain the average voltage change rate of all single cells during a detection cycle; obtain the target voltage change rate of a target battery during the detection cycle, wherein the target battery is the single cell corresponding to the lowest battery temperature during the detection cycle; confirm whether the voltage change rate difference is less than a preset voltage change rate threshold; wherein the voltage change rate difference is the absolute value of the difference between the target voltage change rate and the average voltage change rate; if not, determine that the battery temperatures corresponding to multiple temperature collection points are normal; if so, confirm that the battery temperatures corresponding to multiple temperature collection points are abnormal.

[0064] Optionally, after confirming that the battery temperatures corresponding to the multiple temperature collection points are abnormal, the battery management system 10 is configured to use the average battery temperature as a corrected temperature value of the target battery.

[0065] The present invention also provides a battery temperature analysis method, which can be applied to but not limited to Figure 1 or Figure 2 The battery temperature analysis device shown is used in the battery management system. Figure 3 , Figure 3 The flowchart of the battery temperature analysis method provided by the embodiment of the present invention is as follows: The battery temperature analysis method includes: S110, S120, S130, S140, S150 and S160, which are described in detail as follows.

[0066] S110, obtaining battery temperatures corresponding to a plurality of temperature collection points in the battery module within a detection period.

[0067] Optionally, the battery module includes a plurality of single cells, and each single cell is provided with at least one temperature collection point.

[0068] S120, obtaining an average battery temperature and a minimum battery temperature corresponding to a plurality of temperature collection points.

[0069] S130, determining whether the temperature difference is less than a preset temperature threshold. If yes, executing S140; if no, executing S150.

[0070] The temperature difference is the difference between the average battery temperature and the minimum battery temperature.

[0071] S140, determining that the battery temperatures corresponding to the multiple temperature collection points are normal.

[0072] It should be noted that when the temperature difference is less than the preset temperature threshold, it means that the battery temperatures corresponding to all temperature collection points are normal, and each serial number battery can be assigned a value according to the temperature uploaded by the battery module management unit BMU.

[0073] S150, obtaining electrical property data of each single battery in the battery module within a detection period.

[0074] When the temperature difference is greater than or equal to the preset temperature threshold, it is necessary to further combine other electrical property data to determine whether the battery temperatures corresponding to multiple temperature collection points are abnormal. Therefore, it is necessary to obtain the electrical property data of each single cell in the battery module during the detection period.

[0075] S160, combining the electrical property data of each single battery, confirming whether the battery temperatures corresponding to the multiple temperature collection points are abnormal.

[0076] The battery temperature analysis method provided in the embodiment of the present invention uses the battery average temperature and a preset temperature threshold (also called a temperature redundancy constant) to screen out abnormal battery temperature values. It can also use the electrical property data of the single cell to determine whether the battery with abnormal temperature is damaged, thereby identifying whether the abnormal temperature value is valid data or a false alarm, thereby ensuring the accuracy of the temperature data.

[0077] In an optional implementation, the electrical property data of the single cell is voltage data of the single cell.

[0078] On this basis, regarding the content in S160, the embodiment of the present invention also provides an optional implementation method. Please refer to the following, S160, combining the electrical property data of each single battery, confirming whether the battery temperature corresponding to multiple temperature collection points is abnormal, including: S161 to S165, which are specifically described as follows.

[0079] S161, obtaining the average voltage change rate of all single cells during a detection period.

[0080] The voltage acquisition unit 40 acquires the voltage of the single cells in the battery module and reports it to the battery management system 10. The battery management system 10 counts the time required for each single cell voltage to increase or decrease by 0.1V, and calculates the single cell voltage change rate (V / s), which is updated in real time. The voltage change rate of all single cells is averaged, i.e., the average voltage change rate.

[0081] S162, obtaining a target voltage change rate of the target battery during a detection cycle.

[0082] The target battery is the single cell corresponding to the lowest battery temperature during the detection cycle.

[0083] S163, confirm whether the voltage change rate difference is less than a preset voltage change rate threshold. If not, execute S164; if so, execute S165.

[0084] The voltage change rate difference is the absolute value of the difference between the target voltage change rate and the average voltage change rate.

[0085] S164, determining that the battery temperatures corresponding to the multiple temperature collection points are normal.

[0086] Each serial numbered battery may be assigned a value according to the temperature uploaded by the battery module management unit BMU.

[0087] S165, confirming that the battery temperatures corresponding to the multiple temperature collection points are abnormal.

[0088] In the embodiment of the present invention, it is determined whether the battery with abnormal temperature is damaged by using the voltage change rate threshold, thereby identifying whether the abnormal temperature value is valid data or a false alarm.

[0089] In an optional implementation, after confirming that the battery temperatures corresponding to the multiple temperature collection points are abnormal, the battery temperature analysis method further includes: S170, which is specifically as follows.

[0090] S170: Taking the average battery temperature as the corrected temperature value of the target battery.

[0091] Optionally, other serial number batteries are assigned temperatures according to the temperatures uploaded by the battery module management unit BMU.

[0092] In the battery temperature analysis method and device provided in the embodiment of the present invention, it is possible to effectively identify erroneous temperature data and prevent the battery system from making erroneous decisions due to abnormal temperature sampling. The temperature sampling fault circuit can be located and recorded, providing convenience for regular maintenance and overhaul. The voltage change rate can also provide data support for battery health analysis and improve battery service life analysis.

[0093] In summary, the battery temperature analysis method and device provided by the embodiment of the present invention obtains the battery temperature corresponding to multiple temperature collection points in the battery module within the detection period; obtains the battery average temperature and the battery minimum temperature corresponding to multiple temperature collection points; when the temperature difference is less than the preset temperature threshold, determines that the battery temperature corresponding to the multiple temperature collection points is normal, wherein the temperature difference is the difference between the battery average temperature and the battery minimum temperature. The battery average temperature and the preset temperature threshold (also called the temperature redundancy constant) are used to filter the battery temperature abnormal value, so as to identify whether the temperature abnormal value is valid data or a false alarm, thereby ensuring the accuracy of the temperature data.

[0094] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0095] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A battery temperature analysis method, characterized in that: The method comprises: Obtain the battery temperatures corresponding to multiple temperature collection points in the battery module during the detection cycle; Obtain the average battery temperature and the minimum battery temperature corresponding to multiple temperature collection points; When the temperature difference is less than a preset temperature threshold, it is determined that the battery temperatures corresponding to the multiple temperature collection points are normal, wherein the temperature difference is the difference between the average battery temperature and the lowest battery temperature.

2. The battery temperature analysis method according to claim 1, characterized in that: The battery module includes a plurality of single cells, each of which is provided with at least one temperature collection point, and the method further includes: When the temperature difference is greater than or equal to a preset temperature threshold, obtaining electrical property data of each single battery in the battery module within a detection period; Combined with the electrical property data of each single battery, confirm whether the battery temperature corresponding to multiple temperature collection points is abnormal.

3. The battery temperature analysis method according to claim 2, characterized in that: The electrical property data of the single cell is voltage data of the single cell.

4. The battery temperature analysis method according to claim 3, characterized in that: The step of combining the electrical property data of each single battery and confirming whether the battery temperatures corresponding to the multiple temperature collection points are abnormal includes: Obtain the average voltage change rate of all single cells during the detection cycle; Obtaining a target voltage change rate of a target battery within a detection period, wherein the target battery is a single cell corresponding to the lowest battery temperature within the detection period; Confirm whether the voltage change rate difference is less than a preset voltage change rate threshold; wherein the voltage change rate difference is an absolute value of a difference between the target voltage change rate and the average voltage change rate; If not, it is determined that the battery temperatures corresponding to the multiple temperature collection points are normal.

5. The battery temperature analysis method according to claim 4, characterized in that: The step of combining the electrical property data of each single battery and confirming whether the battery temperatures corresponding to the multiple temperature collection points are abnormal also includes: If the voltage change rate difference is less than the preset voltage change rate threshold, it is confirmed that the battery temperatures corresponding to the multiple temperature collection points are abnormal.

6. The battery temperature analysis method according to claim 5, characterized in that: After confirming that the battery temperatures corresponding to the multiple temperature collection points are abnormal, the method further includes: The battery average temperature is used as the corrected temperature value of the target battery.

7. A battery temperature analysis device, characterized in that: The battery temperature analysis device comprises a battery module management unit and a battery management system, and the battery management system is connected to the battery module management unit; The battery module management unit is used to obtain the battery temperatures corresponding to multiple temperature collection points in the battery module within the detection period, and transmit the obtained battery temperatures to the battery management system; The battery management system is used to obtain battery temperatures corresponding to multiple temperature collection points transmitted by the battery module management unit; The battery management system is used to obtain the average battery temperature and the minimum battery temperature corresponding to multiple temperature collection points; The battery management system is used to determine that the battery temperatures corresponding to the multiple temperature collection points are normal when the difference between the battery average temperature and the battery minimum temperature is less than a preset temperature threshold.

8. The battery temperature analysis device according to claim 7, characterized in that: The battery module includes a plurality of single cells, each of which is provided with at least one temperature collection point; The battery module management unit is used to detect the electrical property data of each single battery in the battery module within a cycle, and transmit the acquired battery temperature and electrical property data to the battery management system; The battery management system is used to obtain the electrical property data of each single battery transmitted by the battery module management unit; The battery management system is used to combine the electrical property data of each single battery to confirm whether the battery temperature corresponding to multiple temperature collection points is abnormal.

9. The battery temperature analysis device according to claim 8, characterized in that: The electrical property data of the single cell is voltage data of the single cell; The battery management system is used to obtain the average voltage change rate of all single cells during a detection cycle; obtain the target voltage change rate of a target battery during the detection cycle, wherein the target battery is the single cell corresponding to the lowest battery temperature during the detection cycle; confirm whether the voltage change rate difference is less than a preset voltage change rate threshold; wherein the voltage change rate difference is the absolute value of the difference between the target voltage change rate and the average voltage change rate; if not, determine that the battery temperatures corresponding to multiple temperature collection points are normal; if so, confirm that the battery temperatures corresponding to multiple temperature collection points are abnormal.

10. The battery temperature analysis device according to claim 9, characterized in that: After confirming that the battery temperatures corresponding to the multiple temperature collection points are abnormal, the battery management system is used to use the average battery temperature as a corrected temperature value of the target battery.

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