A battery safety early warning method, device and vehicle

Abstract

The application provides a battery safety early warning method and device and a vehicle, and relates to the technical field of new energy vehicles.The application obtains operation condition data including a battery charging and discharging signal, segments according to a current time current change rate <= a preset value and frame number >= 2, and obtains each charging segment;characteristic values of each charging segment of a single battery are calculated, the voltage change value dV and the frame number of each charging segment of the single battery with the lowest voltage are read and calculated, and the characteristic value F = dV / (frame number-1) is calculated;the first threshold value is set, if the characteristic value F is less than the first threshold value, early warning is not needed, if the characteristic value F of a certain characteristic value is greater than the first threshold value, the characteristic value of all single batteries is calculated, compared with the first threshold value, and the code of all single batteries greater than the first threshold value is early warned and output.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy vehicles, in particular to a battery safety warning method, device and vehicle. BACKGROUND

[0002] New energy electric vehicles generally use power batteries, but the number of accidents caused by power battery thermal runaway leading to vehicle self-ignition is also increasing. At present, the power battery is mainly controlled by the battery management system (BMS), and the BMS can only alarm the power battery anomaly by setting the threshold value in advance. The thermal runaway of the power battery often occurs in an abnormal accumulation process, so it is very important to identify the abnormality of the power battery in advance to avoid the thermal runaway of the power battery.

[0003] At present, the BMS does not use high-performance processors and large storage devices due to cost considerations, resulting in the following shortcomings of the BMS: 1. Small storage capacity, unable to store full life cycle data; 2. Poor computing power, unable to load complex algorithms and perform model warning. 3. The abnormal threshold is set in advance, which is difficult to match the full life cycle state. SUMMARY

[0004] In view of the defects in the prior art, the purpose of the present application is to provide a battery safety warning method, which specifically comprises the following steps:

[0005] Step 1: obtaining battery operating condition data, the operating condition data including battery charging and discharging signals;

[0006] Step 2: classifying and screening the operating condition data: identifying the charging condition of the vehicle according to the battery charging and discharging signals, and screening the charging condition data with state of charge (SOC) ≥ 95% and full charge;

[0007] Step 3: segmenting the data screened in step 2, and grouping a segment according to the current time current change rate ≤ preset value and frame number ≥ 2 to obtain each charging segment;

[0008] Step 4: calculating the feature value F of each charging segment of the single battery, reading the data of the single battery with the lowest voltage, calculating the voltage change value dV and the frame number, and calculating the feature value according to F = dV / (frame number-1);

[0009] Step 5: data comparison and warning, setting a first threshold value and comparing it with the feature value, if the feature value F is less than the first threshold value, no warning is needed, if a certain feature value F is greater than the first threshold value, a warning signal is output.

[0010] Further, step 1 further comprises data cleaning, cleaning the obtained operating condition data, including deleting repeated values, interpolating, replacing missing values or summarizing abnormal values.

[0011] Further, step 5 further comprises: if a certain feature value F is greater than the first threshold value, calculating the feature value for all single batteries and comparing with the first threshold value, and outputting the warning of all single battery codes greater than the first threshold value.

[0012] Further, the preset value in step 3 is 20%.

[0013] Further, the first threshold value in step 5 is 0.

[0014] The application further provides a battery safety warning device, comprising a processor and a memory, the memory is coupled with the processor, the memory is used for storing computer readable instructions, when the processor reads the computer readable instructions from the memory, the battery safety warning device executes the aforementioned battery safety warning method.

[0015] The application further provides a vehicle, comprising a vehicle and the aforementioned battery safety warning device.

[0016] The application further provides a computer storage medium for enabling a computer to execute the aforementioned battery safety warning method.

[0017] The application has the beneficial effect that the application calculates and identifies the abnormal state of the single battery through pre-processing and setting of the charging section, reduces the consumption of computing resources, reduces the cost of monitoring and warning, and can significantly control and reduce the proportion of thermal runaway of the battery. BRIEF DESCRIPTION OF DRAWINGS

[0018] Other features, objects and advantages of the application will become more apparent from the following detailed description of non-limiting embodiments, made with reference to the following drawings:

[0019] Figure 1 It is a battery warning prevention schematic diagram of the first embodiment of the application;

[0020] Figure 2 It is a battery each charging section signal and feature value calculation table of the first embodiment of the application;

[0021] Figure 3 It is a schematic diagram of the second embodiment of the application; DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the embodiments of the application more clear, the technical scheme of the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are part of the embodiments of the application, not all. The components of the embodiments of the application described and shown in the drawings here can be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of embodiments of the application provided in the accompanying drawings is not intended to limit the scope of the application as claimed, but merely represents selected embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the application.

[0024] It should be noted that similar reference numbers 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 subsequent drawings. In addition, all directional indications (such as up, down, left, right, front, back, bottom, etc.) in the application are only used to explain the relative positional relationship, movement, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications also change accordingly. Further, the description of "first", "second", etc. in the application is only for description purposes and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features.

[0025] Embodiment 1:

[0026] As shown in Figure 1 , the embodiment provides a battery safety warning method, which specifically comprises:

[0027] S1: Obtain new energy vehicle working condition data, which includes signals sent by battery, motor, engine, alarm and other modules, and the signal sending period, i.e. the time interval between two frames, is 1s. In other embodiments, the above-mentioned signal sending period can also be 2s, 10s or 30s.

[0028] S2: Working condition data cleaning, mainly including: deleting repeated values, interpolating or replacing missing values, and inductively converting abnormal values.

[0029] S3: Working condition data classification, according to the vehicle charging and discharging signals in the cleaned working condition data, the vehicle working condition data is classified to obtain charging working condition, driving working condition and static working condition, and the vehicle charging and discharging signal meanings in the embodiment correspond to 1: parking charging; 2: driving charging; 3: no charging state; 4: charging completion, so the embodiment uses 1 and 4 for working condition classification, as shown in Figure 2 .

[0030] S4: Charging working condition screening, identifying the SOC signal in the charging working condition, and screening the charging working condition with SOC≥95% and full charging, to obtain the screened charging working condition. Since it is the end of charging, the time occupied by this working condition is relatively small and will not exceed 50 frames, and the data required for calculation is relatively small compared with other methods, which can reduce the consumption of computing resources.

[0031] S5: Charging condition segmentation, after screening the charging condition, segmenting according to the total current, segmenting according to the total current change <= 20%, as long as the next frame current change is less than 20% of the current frame, it can be classified into the same segment.

[0032] S6: First select the lowest voltage single battery to calculate the voltage change value dV of each segment, for example: dV = 3.384-3.406 = -0.022V, the specific value is shown in Figure 2

[0033] S7: Find the characteristic value F of the single battery with the lowest voltage, for example: F = dV / (frame number-1) = -0.022 / 10 = -0.0022V, and compare it with the threshold value to get the state of the automobile power battery. The threshold value is 0 in this embodiment, and when F < 0, it is considered that the automobile power battery needs to be warned.

[0034] S8: Calculate the characteristic value of all single batteries of the automobile power battery, and compare it with a certain threshold value. The single battery code with a characteristic value greater than the threshold value is an abnormal battery code, and the code is output for early warning.

[0035] Embodiment 2: A battery safety warning device, comprising an acquisition module, a processing module and a warning module, the processing module is used for processing the data of the acquisition module, and the warning module is used for visualizing the prediction result. When the acquisition module, the processing module and the warning module work, the battery power warning method in embodiment 1 can be executed.

[0036] Embodiment 3: A vehicle comprising the battery safety warning device of embodiment 2. The methods in embodiment 1 are applicable to the vehicle of the embodiment.

[0037] Embodiment 4: The embodiment provides a storage medium, which stores programs or instructions, and the programs or instructions are executed by a processor to realize the steps of the method in embodiment 1.

[0038] In the embodiments of the application, the charging segment data is obtained by preprocessing the automobile condition data; the characteristic value of the lowest single battery in each segment is obtained according to the charging segment data; when the characteristic value is greater than a certain threshold value, the automobile is warned according to the calculated characteristic value. After the automobile power battery is warned, all single batteries are calculated to identify all single abnormalities in advance. On the one hand, only calculating a single battery in the early stage can reduce the consumption of computing resources, and on the other hand, it can reduce the proportion of thermal runaway.

[0039] The specific embodiments of the application are described above, and through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the application.​

Claims

1. A battery safety warning method, characterized in that, The method comprises the following steps: S1: obtaining battery operation condition data, wherein the condition data comprises battery charging and discharging signals; S2: classifying and screening the condition data: identifying the charging condition of the vehicle according to the battery charging and discharging signals, and screening the charging condition data with a state of charge (SOC) ≥ 95% and full charging; S3: segmenting the data screened in S2, and grouping each charging segment according to a current change rate ≤ a preset value and a frame number ≥ 2; S4: calculating the characteristic value F of each charging segment of the single battery, reading the data of the single battery with the lowest voltage, calculating the voltage change value dV and the frame number, and calculating the characteristic value according to F = dV / (frame number-1); S5: data comparison and early warning, setting a first threshold value and comparing it with the characteristic value, if the characteristic value F is less than the first threshold value, no early warning is needed, and if the characteristic value F is greater than the first threshold value, an early warning signal is output.

2. The battery safety early warning method according to claim 1, wherein: The S1 step further comprises data cleaning, which comprises deleting repeated values, interpolating, replacing missing values, or inducing and converting abnormal values.

3. The battery safety early warning method according to claim 1, wherein: The S5 step further comprises: if the characteristic value F is greater than the first threshold value, the characteristic value is calculated for all single batteries, compared with the first threshold value, and the model number of all single batteries greater than the first threshold value is output as an early warning.

4. The battery safety warning method of claim 1, wherein: The preset value in the step S3 is 20%.

5. The battery safety warning method of claim 1 or 3, wherein: The first threshold value in the step S5 is 0.

6. A battery safety warning device, characterized by, It comprises: A processor and a memory, wherein the memory is coupled with the processor, and the memory is used to store computer readable instructions, when the processor reads the computer readable instructions from the memory, the battery safety early warning device executes the method according to any one of claims 1-5.

7. A vehicle characterized by comprising: The vehicle comprises the vehicle itself and the battery safety early warning device according to claim 6.

8. A computer storage medium, characterized in that The computer storage medium is used to make the computer execute the battery safety early warning method according to any one of claims 1-5.

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