CN-122008874-A - Battery management system and battery thermal runaway early warning method

CN122008874ACN 122008874 ACN122008874 ACN 122008874ACN-122008874-A

Abstract

The application discloses a battery management system and a battery thermal runaway early warning method, which relate to the technical field of battery safety management, wherein the battery management system comprises a temperature sensor and a controller, and the temperature sensor is in communication connection with the controller; the temperature sensor is used for acquiring temperature data of the vehicle battery in a current period, the controller is used for determining a thermal runaway mode according to the temperature data, the thermal runaway mode comprises a mechanical runaway mode, an electric runaway mode and a high Wen Shikong mode, determining a target adjusting coefficient according to the thermal runaway mode, determining a target thermal runaway threshold according to the target adjusting coefficient and a preset thermal runaway threshold, and generating an early warning instruction which is used for indicating to send out battery thermal runaway early warning to a user when the temperature rise rate of the later period is larger than the target thermal runaway threshold.

Inventors

LU WENTAO
SHI HUILI
XIN XIAODONG
ZHANG ZUOWEI

Assignees

中创新航科技集团股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260331

Claims (15)

1. A battery management system, comprising a temperature sensor and a controller, wherein the temperature sensor is in communication connection with the controller; the temperature sensor is used for acquiring temperature data of the vehicle battery in the current period; the controller is used for: Determining a thermal runaway mode from the temperature data, the thermal runaway mode including a mechanical runaway mode, an electrical runaway mode, and a high Wen Shikong mode; determining a target regulating coefficient according to the thermal runaway mode, and determining a target thermal runaway threshold according to the target regulating coefficient and a preset thermal runaway threshold; And under the condition that the temperature rise rate of the later period is greater than the target thermal runaway threshold, generating an early warning instruction, wherein the early warning instruction is used for indicating to send out the battery thermal runaway early warning to a user.
2. The battery management system of claim 1, wherein the controller is further configured to determine the thermal runaway mode by: determining the mechanical runaway mode as the thermal runaway mode if it is determined that the temperature data indicates that the temperature value of the vehicle battery within the current period of time is a first temperature characteristic, wherein the first temperature characteristic is used to indicate that the temperature value is always in a first temperature interval; Determining the electric runaway mode as the thermal runaway mode if it is determined that the temperature data indicates that the temperature value of the vehicle battery within the current period is a second temperature characteristic, wherein the second temperature characteristic is used to indicate that the temperature value continuously rises, and the temperature rise value is greater than a preset temperature difference value; And determining the high-temperature runaway mode as the thermal runaway mode under the condition that the temperature data indicate that the temperature value of the vehicle battery in the current period is a third temperature characteristic, wherein the third temperature characteristic is used for indicating that the temperature value is always in a second temperature interval, and the lower limit value of the second temperature interval is larger than the upper limit value of the first temperature interval.
3. The battery management system of claim 2, wherein the controller is further configured to determine the thermal runaway mode by: Inputting the temperature data into a thermal runaway mode prediction model to obtain a thermal runaway mode prediction result output by the thermal runaway mode prediction model under the condition that the temperature data indicate that the temperature value of the vehicle battery in the current period is a fourth temperature characteristic, wherein the fourth temperature characteristic is other temperature characteristics except the first temperature characteristic, the second temperature characteristic and the third temperature characteristic, and the thermal runaway mode prediction model is a pre-trained probability for predicting and outputting the temperature data to accord with the temperature characteristics of each thermal runaway mode; And determining the thermal runaway mode according to the thermal runaway mode with the highest probability in the thermal runaway mode prediction result.
4. The battery management system of claim 3 wherein the controller is further configured to determine the target adjustment factor by: acquiring a current state of charge value of the vehicle battery; Determining a target mapping relation from a plurality of mapping relations according to the current state of charge value, wherein the plurality of mapping relations are used for recording adjustment coefficients preset for different thermal runaway modes of the vehicle battery under different states of charge, and the target mapping relation is used for recording adjustment coefficients preset for the vehicle battery under the current state of charge value; And determining the target adjusting coefficient according to the target mapping relation.
5. The battery management system of claim 4 wherein the controller is further configured to determine the target thermal runaway threshold by: Acquiring a first adjustment coefficient corresponding to the mechanical runaway mode, a second adjustment coefficient corresponding to the electric runaway mode and a third adjustment coefficient corresponding to the high-temperature runaway mode from the target mapping relation; Determining the first adjustment coefficient as the target adjustment coefficient in the event that the thermal runaway mode is determined to be the mechanical runaway mode; or determining the second adjustment coefficient as the target adjustment coefficient in the event that the thermal runaway mode is determined to be the electrical runaway mode; Or determining the third adjustment coefficient as the target adjustment coefficient in the case where the thermal runaway mode is determined to be the high temperature runaway mode; and determining the target thermal runaway threshold according to the product of the target regulating coefficient and the preset thermal runaway threshold.
6. The battery management system of claim 5 wherein the controller is further configured to determine the target adjustment factor by: Determining that the thermal runaway mode is a multi-dimensional thermal runaway mode when the thermal runaway mode prediction result indicates that the probability of at least two thermal runaway modes is greater than a preset probability; And determining the target regulating coefficient according to the probability of each thermal runaway mode in the at least two thermal runaway modes and the regulating coefficient corresponding to each thermal runaway mode.
7. The battery management system of claim 6 wherein the controller is further configured to determine the target adjustment factor by: And taking the probability of each thermal runaway mode as a weighting coefficient, and carrying out weighted summation on the adjusting coefficient corresponding to each thermal runaway mode to obtain the target adjusting coefficient.
8. The battery management system of claim 4, further comprising a data acquisition module configured to: acquiring experimental data of thermal runaway experiments of the vehicle battery under different charge states, wherein the thermal runaway experiments are used for testing the thermal runaway data of the vehicle battery under different thermal runaway models; And determining the preset thermal runaway threshold and the mapping relations according to the experimental data.
9. The battery management system of claim 8, wherein the data acquisition module is further configured to acquire the experimental data by: Acquiring first experimental data corresponding to the mechanical runaway mode, wherein the first experimental data is thermal runaway data of the vehicle battery under the condition that battery structures in different charge states are mechanically damaged; acquiring second experimental data corresponding to the electric runaway mode, wherein the second experimental data is the thermal runaway data of the vehicle battery under the condition that the electric parameters of different charge states are abnormal; Acquiring third experimental data corresponding to the high-temperature runaway mode, wherein the third experimental data is thermal runaway data of the vehicle battery under the condition that different charge states are in a third temperature interval; and determining the experimental data according to the first experimental data, the second experimental data and the third experimental data.
10. The battery management system of claim 1, wherein the controller is further configured to generate the early warning instructions by: in the latter period, calculating the temperature rise rate by adopting a time sliding window, wherein the time window of the time sliding window is of a preset duration, and the temperature rise rate is the temperature rise rate in the time window; And generating the early warning instruction under the condition that the temperature rise rate is always larger than the target thermal runaway threshold value during the preset sliding time period of the time sliding window.
11. The battery management system of claim 1, wherein the temperature sensor is disposed at a geometric center position of a maximum surface of the vehicle battery not covered by the heater chip for collecting the temperature data at a preset sampling period.
12. The battery management system of claim 1, further comprising a flame sensor and a smoke sensor, each in communication with the controller, the controller further configured to, after generating the pre-warning instructions: cutting off a high-voltage loop of the vehicle battery, and stopping charging or heating the vehicle battery; Controlling the vehicle battery to actively discharge with constant power through a preset discharge resistor until the voltage of the vehicle battery drops below a safe voltage threshold; and sending a fire extinguishing instruction to a battery thermal management system to enable the battery thermal management system to start a fire extinguishing device under the condition that the flame sensor detects that the installation space of the vehicle battery is on fire and/or under the condition that the smoke sensor detects that the installation space of the vehicle battery is on smoke.
13. The battery management system of claim 1, wherein the controller, after generating the early warning instructions, is further configured to: starting a high-speed data acquisition mode, and recording multidimensional data of the vehicle battery in a thermal runaway period at a preset sampling frequency; aligning the multidimensional data according to a time axis to generate a data packet containing a time stamp, a data identifier and a data check code; and uploading the data packet to a cloud server and synchronously storing the data packet to a local memory.
14. A battery thermal runaway warning method, characterized in that it is applied to a battery management system, comprising: Acquiring temperature data of a vehicle battery in a current period; Determining a thermal runaway mode from the temperature data, the thermal runaway mode including a mechanical runaway mode, an electrical runaway mode, and a high Wen Shikong mode; determining a target regulating coefficient according to the thermal runaway mode, and determining a target thermal runaway threshold according to the target regulating coefficient and a preset thermal runaway threshold; And under the condition that the temperature rise rate of the later period is greater than the target thermal runaway threshold, generating an early warning instruction, wherein the early warning instruction is used for indicating to send out the battery thermal runaway early warning to a user.
15. An electric vehicle comprising a battery and the battery management system of any one of claims 1-13 for thermal runaway monitoring of the battery.

Description

Battery management system and battery thermal runaway early warning method Technical Field The application relates to the technical field of battery safety management, in particular to a battery management system and a battery thermal runaway early warning method. Background With the large-scale popularization of electric automobiles and energy storage power stations, the lithium ion battery is used as a core energy storage carrier, the safety problem of the lithium ion battery is increasingly remarkable, the thermal runaway is used as the most destructive failure mode of the battery, and once the battery is generated, smoke, fire or even explosion is often accompanied, so that personal safety and public property safety are seriously threatened. At present, a main stream battery management system generally adopts a threshold value judging method based on temperature rise rate to carry out thermal runaway monitoring, the judging standard is single, thermal runaway characteristics under different causes cannot be distinguished, the temperature evolution rules of the battery under different triggering modes have obvious differences, and the unified temperature rise rate threshold value is adopted to judge that misjudgment or missed judgment easily occurs, so that early warning time is inaccurate. Therefore, in the related art, there is a technical problem of how to accurately perform thermal runaway warning on a vehicle battery. Aiming at the technical problem of accurately carrying out thermal runaway early warning on a vehicle battery in the related art, no effective solution is proposed yet. Disclosure of Invention The embodiment of the application provides a battery management system and a battery thermal runaway early warning method, which at least solve the technical problem of how to accurately early warn the thermal runaway of a vehicle battery in the related technology. According to one embodiment of the application, a battery management system is provided, and comprises a temperature sensor and a controller, wherein the temperature sensor is in communication connection with the controller, the temperature sensor is used for acquiring temperature data of a vehicle battery in a current period, the controller is used for determining a thermal runaway mode according to the temperature data, the thermal runaway mode comprises a mechanical runaway mode, an electric runaway mode and a high Wen Shikong mode, a target adjustment coefficient is determined according to the thermal runaway mode, a target thermal runaway threshold is determined according to the target adjustment coefficient and a preset thermal runaway threshold, and an early warning instruction is generated when the temperature rise rate of a later period is larger than the target thermal runaway threshold and is used for indicating to send battery thermal runaway early warning to a user. According to another embodiment of the application, a battery thermal runaway early warning method is provided, and is applied to a battery management system, wherein the battery thermal runaway early warning method comprises the steps of obtaining temperature data of a vehicle battery in a current period, determining a thermal runaway mode according to the temperature data, wherein the thermal runaway mode comprises a mechanical runaway mode, an electric runaway mode and a high Wen Shikong mode, determining a target adjusting coefficient according to the thermal runaway mode, determining a target thermal runaway threshold according to the target adjusting coefficient and a preset thermal runaway threshold, and generating an early warning instruction when the temperature rise rate of the later period is larger than the target thermal runaway threshold, wherein the early warning instruction is used for indicating to send battery thermal runaway early warning to a user. According to another embodiment of the present application, there is also provided an electric vehicle including a battery and the battery management system of the above embodiment, the battery management system being configured to monitor the battery for thermal runaway. The embodiment of the application provides a battery management system, which comprises a temperature sensor and a controller, wherein the temperature sensor is in communication connection with the controller, the temperature sensor is used for acquiring temperature data of a vehicle battery in a current period, the controller is used for determining a thermal runaway mode according to the temperature data, the thermal runaway mode comprises a mechanical runaway mode, an electric runaway mode and a high Wen Shikong mode, a target regulating coefficient is determined according to the thermal runaway mode, a target thermal runaway threshold is determined according to the target regulating coefficient and a preset thermal runaway threshold, and an early warning instruction is generated when the temperature rise rate in a later perio