Automobile and power battery deformation monitoring and active power-off protection system thereof
By integrating strain gauges, fiber optic strain gauges, or pressure sensors with control modules and active power-off modules in the battery system, the problems of monitoring lag and passivity in battery deformation monitoring systems are solved, enabling early warning and active protection against battery thermal runaway, improving safety and reducing costs.
Patent Information
- Application Number
- CN202510989971.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-17
- Publication Date
- 2025-11-28
AI Technical Summary
Existing battery deformation monitoring systems suffer from monitoring lag and passivity, lacking an active power-off mechanism. This results in delayed thermal runaway protection and passive safety protection, and the deployment of high-precision sensors is difficult, highlighting the contradiction between cost and reliability.
By combining strain gauges, fiber optic strain gauges, or pressure sensors with control modules and active power-off modules, the mechanical deformation of the battery cell is monitored and converted into a measurable electrical signal. Based on the standard deformation electrical signal, different levels of battery cell deformation alarms and active power-off are triggered to achieve an active defense chain.
It enables early warning and active power cut-off for battery thermal runaway, avoids heat propagation, improves safety and reliability, and reduces costs.
Smart Images
Figure CN121035931A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the field of automobiles, and particularly relates to an automobile and a power battery deformation monitoring and active power-off protection system thereof. BACKGROUND
[0002] The battery deformation monitoring system of the prior art only has a monitoring function, and has the following defects, resulting in delayed thermal runaway protection and passive safety protection, which is specifically manifested as follows: 1. Monitoring hysteresis: The time slots of the deformation signal and the thermal runaway are not effectively utilized. The prior art relies on temperature or voltage threshold triggering, and most battery deformation monitoring systems only alarm when the battery temperature is greater than 100 DEG C or the voltage drops by more than 20%. However, experiments have shown that the gas generated by the decomposition of the electrolyte before the thermal runaway of the lithium ion battery will cause the deformation of the battery shell, and the deformation signal can be detected 2 hours earlier than the temperature signal. According to GB38031, after applying the extrusion, at least 2 hours need to be observed, and the temperature of all monitoring points is not higher than 60 DEG C, so the deformation signal can be detected 2 hours in advance.
[0003] 2. System passivity: Only alarm function, lack of active power-off mechanism. When a single cell occurs thermal runaway, the existing system only responds by sound and light alarm or reducing the charging / output current, which cannot block the thermal spread, and the electrical connection between the modules is still maintained, resulting in the spread of high temperature between the modules.
[0004] 3. Contradiction between cost and reliability: High-precision sensor deployment is difficult. Although the optical fiber sensor can detect micro-strain, the cost of a single point is high, and a laser demodulation device is required, which cannot be popularized in mass-produced vehicles. The low-cost solution lacks accuracy. The pressure sensor is relatively thick and can only detect macro-bulges, but cannot capture early micro-strains. SUMMARY
[0005] The present application aims to provide an automobile and a power battery deformation monitoring and active power-off protection system thereof, which aims to solve the problem that the battery deformation monitoring system of the prior art only has a monitoring function, resulting in delayed thermal runaway protection and passive safety protection.
[0006] In a first aspect, the present application provides a power battery deformation monitoring and active power-off protection system of an automobile, comprising a control module, a transmitter and an active power-off module electrically connected with the control module, and a strain gauge electrically connected with the transmitter. The strain gauge is used to contact the cells of the power battery of the automobile, and to convert the mechanical deformation of the cells into a measurable original deformation electrical signal; The transmitter is used to receive the original deformation electrical signal output by the strain gauge, and to convert it into a general standard deformation electrical signal after processing; The control module is used to receive the standard deformation electrical signal output by the transmitter, and trigger different levels of cell deformation alarms according to the standard deformation electrical signal and the preset alarm deformation value. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, and the active power-off module is triggered to disconnect the connection between the battery modules.
[0007] In a second aspect, the present invention provides a power battery deformation monitoring and active power-off protection system for automobiles, including a control module and an analyzer and an active power-off module respectively electrically connected to the control module. The system also includes an optical fiber strain gauge electrically connected to the analyzer. Fiber optic strain gauges are used to contact the cells of automotive power batteries, converting the mechanical deformation of the cells into measurable raw deformation electrical signals. The analyzer is used to receive the raw deformation electrical signal output by the fiber optic strain gauge and resolve it into a common standard deformation electrical signal; The control module is used to receive the standard deformation electrical signal output by the analyzer, and trigger different levels of cell deformation alarms according to the standard deformation electrical signal and the preset alarm deformation value. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, and the active power-off module is triggered to disconnect the connection between the battery modules.
[0008] Thirdly, the present invention provides a power battery deformation monitoring and active power-off protection system for automobiles, including a control module, a transmitter electrically connected to the control module and an active power-off module, and the system further includes a pressure sensor electrically connected to the transmitter. Pressure sensors are used to contact the cells of a car's power battery and convert the deformation pressure value of the cell into a measurable raw deformation electrical signal. The transmitter is used to receive the raw deformation electrical signal output by the strain gauge, and after processing, it is converted into a general standard deformation electrical signal; The control module is used to receive the standard deformation electrical signal output by the transmitter, and trigger different levels of cell deformation alarms according to the standard deformation electrical signal and the preset alarm deformation value. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, and the active power-off module is triggered to disconnect the connection between the battery modules.
[0009] Fourthly, the present invention provides a vehicle, the vehicle including the aforementioned vehicle power battery deformation monitoring and active power-off protection system.
[0010] In this invention, an active power-off module and strain gauges are included. The strain gauges are used to contact the battery cells of the vehicle's power battery, converting the mechanical deformation of the cells into measurable raw deformation electrical signals. The control module receives standard deformation electrical signals and triggers different levels of cell deformation alarms based on these signals and preset alarm deformation values. When a preset power-off threshold is exceeded, a power-off is determined, triggering the active power-off module to disconnect the connection between the battery modules. Therefore, an active defense chain is achieved, overcoming the challenges of monitoring lag and passive protection. Attached Figure Description
[0011] Figure 1 This is a functional block diagram of the power battery deformation monitoring and active power-off protection system for automobiles provided in Embodiment 1 of the present invention.
[0012] Figure 2 This is a schematic diagram of the arrangement of one set of strain gauges attached to the center of each battery cell in the power battery deformation monitoring and active power-off protection system for automobiles provided in Embodiment 1 of the present invention.
[0013] Figure 3 This is a schematic diagram of the arrangement of a set of strain gauges covering the boundary area between two adjacent battery cells in the power battery deformation monitoring and active power-off protection system for automobiles provided in Embodiment 1 of the present invention.
[0014] Figure 4 This is a schematic diagram of the arrangement of strain gauges on cells of each battery module in the power battery deformation monitoring and active power-off protection system for automobiles provided in Embodiment 1 of the present invention.
[0015] Figure 5 This is a functional block diagram of the automotive power battery deformation monitoring and active power-off protection system provided in Embodiment 2 of the present invention.
[0016] Figure 6 This is a functional block diagram of the automotive power battery deformation monitoring and active power-off protection system provided in Embodiment 3 of the present invention. Detailed Implementation
[0017] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
[0018] To illustrate the technical solution described in this invention, specific embodiments are described below.
[0019] Please see Figure 1The present invention provides a power battery deformation monitoring and active power-off protection system for automobiles, comprising a control module 11, a transmitter 12 electrically connected to the control module 11, and an active power-off module 13. The system also includes a strain gauge 14 electrically connected to the transmitter 12. The strain gauge 14 is used to contact the battery cell of the car's power battery to convert the mechanical deformation of the battery cell into a measurable raw deformation electrical signal. Transmitter 12 is used to receive the original deformation electrical signal output by the strain gauge, and after processing, it is converted into a general standard deformation electrical signal; The control module 11 is used to receive the standard deformation electrical signal output by the transmitter, and determine whether power needs to be cut off based on the standard deformation electrical signal. If power needs to be cut off, the active power-off module is triggered to disconnect the connection between the battery modules.
[0020] In Embodiment 1 of the present invention, the control module can specifically be used to receive the standard deformation electrical signal output by the transmitter, and trigger different levels of cell deformation alarms according to the standard deformation electrical signal and the preset alarm deformation value. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, and the active power-off module is triggered to disconnect the connection between the battery modules.
[0021] In Embodiment 1 of the present invention, the preset alarm deformation value may include a first threshold, a second threshold and a third threshold, wherein the first threshold is less than the second threshold and the second threshold is less than the third threshold; for example, the first threshold is set to 15% of the third threshold and the second threshold is set to 50% of the third threshold.
[0022] The steps of triggering different levels of cell deformation alarms based on the standard deformation electrical signal and the preset alarm deformation value, and determining that a power outage is required when the preset power-off threshold is exceeded, and triggering the active power-off module to disconnect the connection between the battery modules, specifically include: When the standard deformation electrical signal exceeds the first threshold, an audible and visual alarm is triggered, and the current limit is set to 50%, thereby suppressing the gas production rate and gaining maintenance time. When the standard deformation electrical signal exceeds the second threshold, a cockpit pop-up warning is triggered, and the liquid cooling system is activated, thereby delaying the thermal runaway process. When the standard deformation electrical signal exceeds the third threshold, the active power-off module is triggered to disconnect the connection between the battery modules and report to the cloud, thereby preventing heat spread and avoiding a chain reaction.
[0023] In Embodiment 1 of the present invention, the third threshold can be determined based on a combination of the battery's charge level and its temperature. For example, when the battery's charge level is 0% to 30% and its temperature is <0°C, the third threshold is set to 300 με; when the battery's temperature is 0-45°C, the third threshold is set to 500 με; when the battery's temperature is >45°C, the third threshold is set to 500 με. When the battery's charge level is 30% to 80% and its temperature is <0°C, the third threshold is set to 700 με; when the battery's temperature is 0-45°C, the third threshold is set to 1000 με; when the battery's temperature is >45°C, the third threshold is set to 800 με. When the battery's charge level is 80% to 100% and its temperature is <0°C, the third threshold is set to 1500 με; when the battery's temperature is 0-45°C, the third threshold is set to 2000 με; when the battery's temperature is >45°C, the third threshold is set to 1800 με.
[0024] In Embodiment 1 of the present invention, the control module may be a battery management system (BMS) or a separately configured controller.
[0025] Active power-off modules can be devices that use high-pressure gas to disconnect copper busbars, which are quite common in the market. They can also be implemented using contactors, software-based power-off methods, etc.
[0026] Strain gauges can include resistance strain gauges, fiber Bragg grating strain gauges, piezoelectric thin film strain gauges, etc.
[0027] Strain gauges can be arranged such that one set of strain gauges 22 is attached to the center of each cell 21 to monitor one cell (e.g., Figure 2 As shown), a set of strain gauges 32 is attached between each pair of adjacent cells 31 to cover the boundary area between the two adjacent cells in order to monitor the two adjacent cells (e.g. Figure 3 (as shown), or for each battery module, a preset proportion of cells 41 are fitted with strain gauges 42 to monitor a preset number of cells (such as...). Figure 4 (As shown). Each group of strain gauges may include one or two strain gauges.
[0028] The arrangement of attaching one set of strain gauges to the center of each battery cell is suitable for high-value automotive and high-energy-density battery cells; it also provides high detection redundancy. The arrangement of attaching one set of strain gauges between each pair of adjacent cells to cover the boundary area between the two adjacent cells is suitable for square hard-shell batteries; the detection redundancy is moderate. The arrangement of strain gauges on cells in each battery module with a preset ratio is suitable for cost-sensitive vehicle models; the detection redundancy is low.
[0029] The strain gauge can be parallel or perpendicular to the direction of cell expansion. A reference strain gauge can be attached to the battery bracket to compensate for temperature drift, thereby achieving anti-interference.
[0030] In Embodiment 1 of the present invention, the controller can be of the following model: Huichuan Easy320 (PLC); the transmitter can be of the following model: RunesKee CMCU-06; and the strain gauge can be of the following model: RunesKee BF350-100AA.
[0031] In Embodiment 1 of this invention, an active power-off module and strain gauges are included. The strain gauges are used to contact the battery cells of the vehicle's power battery, converting the mechanical deformation of the cells into measurable raw deformation electrical signals. The control module receives the standard deformation electrical signal output by the transmitter and triggers different levels of cell deformation alarms based on the standard deformation electrical signal and a preset alarm deformation value. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, triggering the active power-off module to disconnect the connection between the battery modules. Therefore, an active defense chain is realized, overcoming the difficulties of monitoring lag and passive protection.
[0032] Please see Figure 5 The second embodiment of the present invention provides a power battery deformation monitoring and active power-off protection system for automobiles, including a control module 51, an analyzer 52 and an active power-off module 53 respectively electrically connected to the control module 51, and the system further includes an optical fiber strain gauge 54 electrically connected to the analyzer 52. The fiber optic strain gauge 54 is used to contact the battery cells of a car's power battery to convert the mechanical deformation of the battery cells into a measurable raw deformation electrical signal. The analyzer 52 is used to receive the raw deformation electrical signal output by the fiber optic strain gauge and analyze it into a general standard deformation electrical signal. The control module 51 is used to receive the standard deformation electrical signal output by the analyzer, and trigger different levels of cell deformation alarms according to the standard deformation electrical signal and the preset alarm deformation value. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, and the active power-off module is triggered to disconnect the connection between the battery modules.
[0033] The second embodiment of the present invention provides a high-precision, high-cost automotive power battery deformation monitoring and active power-off protection system, which is suitable for high-precision scenarios.
[0034] In Embodiment 2 of the present invention, the controller can be the following model: Huichuan Easy320 (PLC); the fiber optic strain gauge can be the following model: Zhixing Technology ZX-FBG-S01D / F.
[0035] Except for the differences described above, Embodiment 2 of the present invention is the same as Embodiment 1 of the present invention.
[0036] In Embodiment 2 of this invention, an active power-off module and a fiber optic strain gauge are included. The fiber optic strain gauge is used to contact the battery cells of the vehicle's power battery, converting the mechanical deformation of the battery cells into measurable raw deformation electrical signals. The control module receives the standard deformation electrical signals output by the analyzer and triggers different levels of battery cell deformation alarms based on the standard deformation electrical signals and preset alarm deformation values. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, triggering the active power-off module to disconnect the connection between the battery modules. Therefore, an active defense chain is realized, overcoming the difficulties of monitoring lag and passive protection.
[0037] Please see Figure 6 The third embodiment of the present invention provides a power battery deformation monitoring and active power-off protection system for automobiles, including a control module 61, a transmitter 62 and an active power-off module 63 respectively electrically connected to the control module 61, and the system further includes a pressure sensor 64 electrically connected to the transmitter 62. Pressure sensor 64 is used to contact the cells of the vehicle's power battery and convert the deformation pressure value of the cells into a measurable raw deformation electrical signal. Transmitter 62 is used to receive the raw deformation electrical signal output by the strain gauge, and after processing, convert it into a general standard deformation electrical signal; The control module 61 is used to receive the standard deformation electrical signal output by the transmitter, and trigger different levels of cell deformation alarms according to the standard deformation electrical signal and the preset alarm deformation value. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, and the active power-off module is triggered to disconnect the connection between the battery modules.
[0038] The third embodiment of the present invention provides a low-cost power battery deformation monitoring and active power-off protection system for automobiles.
[0039] In Embodiment 3 of the present invention, the controller can be the following model: Huichuan Easy320 (PLC); the transmitter can be the following model: RunesKee CMCU-05; and the pressure sensor can be the following model: RunesKee RP-L-110.
[0040] Except for the differences described above, Embodiment 3 of the present invention is the same as Embodiment 1 of the present invention.
[0041] In Embodiment 3 of this invention, an active power-off module and a pressure sensor are included. The pressure sensor is used to contact the battery cells of the vehicle's power battery, converting the deformation pressure value of the battery cells into a measurable raw deformation electrical signal. The control module is used to receive the standard deformation electrical signal output by the transmitter, and trigger different levels of battery cell deformation alarms based on the standard deformation electrical signal and a preset alarm deformation value. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, triggering the active power-off module to disconnect the connection between the battery modules. Therefore, an active defense chain is realized, overcoming the problems of monitoring lag and passive protection.
[0042] This invention also provides a vehicle, which includes the power battery deformation monitoring and active power-off protection system provided in embodiments one, two or three of this invention.
[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A power battery deformation monitoring and active power-off protection system for automobiles, characterized in that, The system includes a control module, a transmitter electrically connected to the control module, and an active power-off module. The system also includes a strain gauge electrically connected to the transmitter. Strain gauges are used to contact the cells of a car's power battery to convert the mechanical deformation of the cells into measurable raw deformation electrical signals. The transmitter is used to receive the raw deformation electrical signal output by the strain gauge, and after processing, it is converted into a general standard deformation electrical signal; The control module is used to receive the standard deformation electrical signal output by the transmitter, and trigger different levels of cell deformation alarms according to the standard deformation electrical signal and the preset alarm deformation value. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, and the active power-off module is triggered to disconnect the connection between the battery modules.
2. The system as described in claim 1, characterized in that, The preset alarm deformation value includes a first threshold, a second threshold, and a third threshold, wherein the first threshold is less than the second threshold, and the second threshold is less than the third threshold; The steps of triggering different levels of cell deformation alarms based on the standard deformation electrical signal and the preset alarm deformation value, and determining that a power outage is required when the preset power-off threshold is exceeded, and triggering the active power-off module to disconnect the connection between the battery modules, specifically include: When the standard deformation electrical signal exceeds the first threshold, an audible and visual alarm is triggered, and the current limit is set to 50%. When the standard deformation electrical signal exceeds the second threshold, a cockpit pop-up warning is triggered, and the liquid cooling system is activated. When the standard deformation electrical signal is greater than the third threshold, the active power-off module is triggered to disconnect the connection between the battery modules and report to the cloud.
3. The system as described in claim 2, characterized in that, The third threshold is determined based on a combination of the battery's charge level and its temperature.
4. The system as described in claim 1, characterized in that, The active power-off module is achieved through a device, contactor, or software-based power-off method that uses high-pressure gas to disconnect the copper busbar.
5. The system as described in claim 1, characterized in that, The strain gauge includes a resistance strain gauge, a fiber optic strain gauge, or a piezoelectric thin film strain gauge.
6. The system as described in claim 1, characterized in that, The strain gauges are arranged such that one set of strain gauges is attached to the center of each cell to monitor one cell, one set of strain gauges is attached between each two adjacent cells to cover the boundary area between the two adjacent cells to monitor two adjacent cells, or strain gauges are attached to a preset proportion of cells in each battery module to monitor a preset number of cells.
7. The system as described in claim 6, characterized in that, The strain gauge is parallel or perpendicular to the cell expansion direction, and a reference strain gauge is attached to the battery bracket to compensate for temperature drift.
8. A power battery deformation monitoring and active power-off protection system for automobiles, characterized in that, The system includes a control module, an analyzer electrically connected to the control module, and an active power-off module. The system also includes an optical fiber strain gauge electrically connected to the analyzer. Fiber optic strain gauges are used to contact the cells of automotive power batteries, converting the mechanical deformation of the cells into measurable raw deformation electrical signals. The analyzer is used to receive the raw deformation electrical signal output by the fiber optic strain gauge and resolve it into a common standard deformation electrical signal; The control module is used to receive the standard deformation electrical signal output by the analyzer, and trigger different levels of cell deformation alarms according to the standard deformation electrical signal and the preset alarm deformation value. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, and the active power-off module is triggered to disconnect the connection between the battery modules.
9. A power battery deformation monitoring and active power-off protection system for automobiles, characterized in that, The system includes a control module, a transmitter electrically connected to the control module, and an active power-off module. The system also includes a pressure sensor electrically connected to the transmitter. Pressure sensors are used to contact the cells of a car's power battery and convert the deformation pressure value of the cell into a measurable raw deformation electrical signal. The transmitter is used to receive the raw deformation electrical signal output by the strain gauge, and after processing, it is converted into a general standard deformation electrical signal; The control module is used to receive the standard deformation electrical signal output by the transmitter, and trigger different levels of cell deformation alarms according to the standard deformation electrical signal and the preset alarm deformation value. When the preset power-off threshold is exceeded, it is determined that power needs to be cut off, and the active power-off module is triggered to disconnect the connection between the battery modules.
10. A car, characterized in that, The vehicle includes a power battery deformation monitoring and active power-off protection system as described in any one of claims 1 to 9.