Electric vehicle, battery thermal runaway management system and method thereof

Abstract

The invention discloses an electric vehicle, a battery thermal runaway management system and a battery thermal runaway management method. The battery thermal runaway management system is applied to a battery module. The battery thermal runaway management system comprises a battery cell, a plurality of temperature sensors and a battery management unit. The plurality of temperature sensors are disposed on the battery module to generate a plurality of temperature values. The battery management unit is connected with the temperature sensor to receive the plurality of temperature values. When the maximum temperature value in the plurality of temperature values is greater than a temperature critical value, the duration of the maximum temperature value greater than the temperature critical value exceeds a time threshold value, and the temperature difference value between the minimum temperature value and the maximum temperature value in the plurality of temperature values is greater than an alarm temperature threshold value, the battery management unit gives an alarm to the battery when the maximum temperature value in the plurality of temperature values is greater than the alarm temperature threshold value. And generating an early warning signal.

Description

Technical Field

[0001] The present application relates to a battery thermal runaway management system, and particularly to a battery thermal runaway management system with a relatively low cost and capable of effectively detecting battery thermal runaway. Background Art

[0002] As the user's demand for battery capacity increases, the energy density of the battery also increases. However, when an internal short circuit occurs in a battery module and a huge amount of energy causes an explosion and a flame erupts, due to the barrier of the packaging shell, it is not easy for the flame to dissipate inside the battery module, and then it spreads to adjacent batteries, causing secondary explosions in the adjacent batteries. In addition to causing secondary explosions in adjacent batteries, a huge amount of energy will also generate gas inside the packaging shell. When the packaging shell is filled with gas and cannot be discharged, the internal pressure of the battery module will abnormally increase and an explosion will occur. Even more seriously, the explosion flame directly sprays outside the battery module and ignites external equipment or substances, triggering secondary combustion or explosion of adjacent external equipment or substances.

[0003] Traditional designs use smoke / gas / pressure sensors to detect and alarm high-temperature gases during battery thermal runaway eruptions. Moreover, with the continuous progress of technology, the rise of environmental, social, and corporate governance (ESG) indicators and environmental awareness, the requirements for battery reuse are getting higher and higher. Therefore, how to reduce the scrap rate of single battery cells and improve the reuse rate, so as to achieve the effect of energy conservation and carbon reduction, is an urgent problem to be solved at present.

[0004] Traditional designs use smoke / gas / pressure sensors to detect and alarm high-temperature gases during battery thermal runaway eruptions. However, the sensing devices are expensive and occupy space. Therefore, how to automatically and effectively guide and detect high-temperature gases during battery thermal runaway eruptions, and simplify the process and reduce costs, is a problem worthy of discussion at present. Summary of the Invention

[0005] In view of the problems mentioned in the background art, the purpose of the present application is to provide an electric vehicle, a battery thermal runaway management system and a method thereof, which can monitor battery thermal runaway in an effective and low-cost manner and give an early warning.

[0006] For the above purpose, the present application provides a battery thermal runaway management system, which is applied to a battery management unit. The battery thermal runaway management system includes a battery module and multiple temperature sensors. The battery module includes battery cells. The multiple temperature sensors are respectively arranged on the battery module to generate multiple temperature sensing signals. The battery management unit is connected to the temperature sensors to receive the multiple temperature sensing signals and generate respective temperature values according to the multiple temperature sensing signals. The battery management unit generates a warning signal when the multiple temperature values satisfy the following formulas. The first formula: T_max≥P1, where T_max is the maximum temperature value among the multiple temperature values, and P1 is the temperature critical value. The second formula: t>t1, where t is the duration that satisfies the first formula, and t1 is the time threshold. The third formula: T_max - T_min≥T_threshold, where T_min is the minimum temperature value among the multiple temperature values, and T_threshold is the alarm temperature threshold.

[0007] For the above purpose, the present application further provides an electric vehicle. The electric vehicle includes a battery thermal runaway management system and a vehicle control system. The battery thermal runaway management system detects multiple temperature values of the battery module and includes a preset temperature critical value, time threshold, and alarm temperature threshold. When the duration that the maximum temperature value among the multiple temperature values is greater than the temperature critical value exceeds the time threshold, and the temperature difference between the minimum temperature value and the maximum temperature value among the multiple temperature values is greater than the alarm temperature threshold, a warning signal is generated. The vehicle control system is connected to the battery thermal runaway management system, and when the vehicle control system receives the warning signal, an alarm notification is triggered.

[0008] For the above purpose, the present application provides a battery thermal runaway management method, which is applied to a battery management unit to manage a battery module, and the battery module includes battery cells. The battery thermal runaway management method includes the following steps. First, multiple temperature sensors are arranged on the battery cells to generate multiple temperature values. Then, a temperature critical value, a time threshold, and an alarm temperature threshold corresponding to the battery module are provided. After that, the maximum temperature value and the minimum temperature value among the multiple temperature values are obtained. Next, the temperature difference between the minimum temperature value and the maximum temperature value is calculated. When the duration that the maximum temperature value is greater than the temperature critical value exceeds the time threshold, and the temperature difference is greater than the alarm temperature threshold, a warning signal is generated.

[0009] In summary, the electric vehicle, battery thermal runaway management system, and method thereof according to the present application can confirm the state of the battery cell through three formulas, which can not only improve the accuracy but also reduce misjudgment. Moreover, the electric vehicle, battery thermal runaway management system, and method thereof according to the present application can monitor battery thermal runaway and give early warnings in an effective and cost - lower manner, which not only meets the regulatory requirements but also reduces hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 FIG. is a schematic block diagram of a battery thermal runaway management system according to an embodiment of the present application.

[0011] Figure 2 FIG. is a schematic flowchart of a battery thermal runaway management method according to an embodiment of the present application.

[0012] Figure 3 FIG. is a schematic flowchart of the steps for obtaining the temperature critical value according to an embodiment of the present application.

[0013] Figure 4 is Figure 1 a schematic curve graph of the simulation results of the battery thermal runaway management system of

[0014] Figure 5 FIG. is a schematic curve graph of the test results of the battery thermal runaway management system according to the present application.

[0015] Figure 6 FIG. is a schematic block diagram of an electric vehicle according to an embodiment of the present application.

[0016] DESCRIPTION OF REFERENCE NUMERALS: 10 - electric vehicle; 14 - vehicle control system; 100, 200 - battery thermal runaway management systems; 110 - battery management unit; 120, 220 - battery modules; 130A, 130B, 130C, 230A, 230B - temperature sensors; 120A, 220A, 220B - battery cells; 240A, 240B - thermal conductive adhesives; A - warning temperature; F - final warning temperature value; L1, L2, L3 - simulation temperature curves; P1 - temperature critical value; R - thermal runaway temperature; S120 - S160, S210 - S230 - steps; t1 - time threshold; W - operating temperature; TDS1, TDS2, TDS3 - actual temperature curves; T_max - T_min - temperature difference. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] Embodiments of the present application will be further explained below in conjunction with the relevant drawings. As much as possible, in the drawings and the specification, the same reference numerals represent the same or similar components. In the drawings, for the sake of simplicity and convenience of marking, the shapes and thicknesses may be exaggerated. It can be understood that the components not specifically shown in the drawings or described in the specification are in the forms known to those of ordinary skill in the art. Those of ordinary skill in the art can make various changes and modifications according to the content of the present application.

[0018] Figure 1 It is a schematic block diagram of a battery thermal runaway management system according to an embodiment of the present application. Please refer to Figure 1 , the battery thermal runaway management system 100 is applied to the battery module 120. The battery module 120 includes a battery management unit 110, a battery cell 120A, and a plurality of temperature sensors 130A, 130B, 130C. The temperature sensors 130A, 130B, 130C are arranged at different positions on the battery cell 120A to generate a plurality of temperature sensing signals. In this embodiment, the temperature sensors 130A, 130B, 130C are, for example, arranged on a printed circuit board (not shown) and the number is 3, but the number and the arrangement position can be adjusted according to requirements, and are not limited thereto. In another embodiment not shown, the temperature sensors 130A, 130B, 130C can also be arranged on the air guide channel or the bus bar of the battery module 120.

[0019] The battery management unit 110 is connected to the temperature sensors 130A, 130B, 130C to receive a plurality of temperature sensing signals, and respectively generate their own temperature values according to the plurality of temperature sensing signals. The battery management unit 110 generates a warning signal when the plurality of temperature values satisfy the following formulas. The first formula: T_max >= P1, where T_max is the maximum temperature value among the plurality of temperature values, and P1 is the temperature critical value. The second formula: t > t1, where t is the duration satisfying the first formula, and t1 is the time threshold. The third formula: T_max - T_min >= T_threshold, where T_min is the minimum temperature value among the plurality of temperature values, and T_threshold is the alarm temperature threshold.

[0020] Figure 2 It is a schematic flowchart of a battery thermal runaway management method according to an embodiment of the present application. Please refer to Figure 1 And Figure 2 , for the sake of convenience of description, the following will Figure 1 use the battery thermal runaway management system of Figure 2 to illustrate Figure 2 the battery thermal runaway management method. That is, Figure 1The battery management unit 110 manages the entire battery module 120. The battery thermal runaway management method includes the following steps. First, step S120 is performed, where a plurality of temperature sensors 130A, 130B, and 130C are set on the battery module 120 to generate a plurality of temperature values. For example, the temperature sensors 130A, 130B, and 130C can first obtain changes in analog signals such as voltage and then generate corresponding temperature values. Then, step S130 is performed, where temperature critical value P1, time threshold t1, and alarm temperature threshold T_threshold corresponding to the battery module 120 are provided. After that, step S140 is performed, where, from the plurality of temperature values, the maximum temperature value T_max and the minimum temperature value T_min are obtained. Then, step S150 is performed, where the temperature difference (T_max - T_min) between the minimum temperature value T_min and the maximum temperature value T

[0021] _max is calculated. Then, step S160 is performed, where when the duration for which the maximum temperature value T_max is greater than the temperature critical value P1 exceeds the time threshold t1 and the temperature difference is greater than the alarm temperature threshold T_threshold, a warning signal is generated.

[0022] Figure 3 FIG. is a schematic flow chart of the steps for obtaining the temperature critical value in an embodiment of the present application, Figure 4 is Figure 1 a schematic curve graph of the simulation results of the battery thermal runaway management system. Please refer to Figure 3 and Figure 4 , for example, the temperature critical value P1 corresponding to the battery module 120 can be obtained by using a computer with a fluid simulation program according to the following steps, and for example, the preset temperature critical value P1 is 90 °C, the time threshold t1 is 40 seconds, and the alarm temperature threshold T_threshold is 20 °C. In Figure 4In it, the horizontal axis of the curve graph is time (unit: second (S)), and the vertical axis is temperature (unit: °C), and for example, it includes three simulation temperature curves L1, L2, and L3 obtained by respectively performing simulation calculations on temperature sensors 130A, 130B, and 130C. First, step S210 is performed to simulate and obtain the operating temperature W and thermal runaway temperature R of the battery cell 120A in the battery module 120. Taking the curve L1 with the largest temperature rise as an example, the operating temperature W and thermal runaway temperature R can be approximately 70 °C and 130 °C respectively. Then, step S220 is performed to simulate and calculate at least 5 minutes of simulation temperature before the battery cell 120A reaches the thermal runaway temperature R fastest as the final warning temperature value F (approximately 105 °C). For example, by backtracking 5 minutes (i.e., approximately at 1000 seconds (S)) from the time (approximately 1300 seconds (S)) to reach the thermal runaway temperature R, the final warning temperature value F (approximately 105 °C) can be read on the vertical axis. Next, step S230 is performed to set the temperature critical value P1 (approximately 90 °C) according to the final warning temperature value F, the operating temperature W, and the operating conditions of the battery module 120, so that the battery cell 120A needs to pass at least 5 minutes and the duration of the time threshold t1 before reaching the temperature critical value P1 before reaching the thermal runaway temperature R. The temperature critical value P1 is less than the final warning temperature value F and greater than the operating temperature W. From Figure 4 It can be seen that after the curve L1 reaches the temperature critical value P1 and after the time threshold t1, the temperature reaches approximately 99 °C, which is the point A marked in the figure, and is called the warning temperature A here. At this time, the warning temperature A is the maximum temperature value T_max. The maximum temperature value T_max (approximately 99 °C, appearing in curve L1) minus the minimum temperature value T_min (approximately 70 °C, appearing in curve L3) is equal to the temperature difference T_max - T_min of approximately 29 °C. The temperature difference (approximately 29 °C) is greater than or equal to the alarm temperature threshold T_threshold (20 °C). The time when the warning temperature A appears in curve L1 is still earlier than the time of the final warning temperature value F (approximately 100 seconds (S) earlier). That is to say, according to Figure 3 the described fluid simulation program, this embodiment can send out a warning signal at least 400 seconds before the occurrence of thermal runaway (i.e., the time when the thermal runaway temperature R appears) (i.e., the time when the warning temperature A is simulated and calculated).

[0023] Figure 5 It is a schematic curve graph of the test results of the battery thermal runaway management system of this application. Please refer to Figure 1 and Figure 5, assume that the general operating temperature W of the battery cell 120A is 70°C, the temperature critical value P1 is 80°C, the time threshold t1 is 40 seconds, and the alarm temperature threshold T_threshold is 20°C. The actual temperature curves TDS1, TDS2, and TDS3 are the results obtained from the temperature sensors 130A, 130B, and 130C respectively after heating the battery cell 120A with a heating sheet of 300W. During the test, when the heating time of the actual temperature curve TDS1 enters 1800 seconds (S), the battery cell 120A starts to expand. Then, when the actual temperature curve TDS1 reaches the temperature critical value P1 (80°C, satisfying the first formula), which is 3253 seconds (S) at this time. Then, to avoid false alarms, it is judged whether the duration of the actual temperature curve TDS1 reaching the temperature critical value P1 reaches the 40S set by the time threshold t1, that is, whether it exceeds the temperature critical value of 80°C within the 40 seconds from 3253 seconds (S) to 3293 seconds (S) of the actual temperature curve TDS1. If the duration of the actual temperature curve TDS1 reaching the temperature critical value P1 reaches the 40 seconds set by the time threshold t1 (satisfying the second formula), and the maximum temperature value T_max is approximately 82°C for the actual temperature curve TDS1, and the minimum temperature value T_min is approximately 40°C for the actual temperature curve TDS3, and the temperature difference between the two exceeds 40°C, that is, exceeds the 20°C set by the alarm temperature threshold T_threshold (satisfying the third formula), a warning alarm can be issued. The time is 5372 seconds from the actual occurrence of the thermal runaway temperature, with a difference of 2079 seconds (about 34.65 minutes) greater than 5 minutes. That is to say, the time from when the battery management unit 110 generates a warning signal to when the battery cell 120A reaches the thermal runaway temperature is at least 5 minutes or more, meeting the safety requirements for power batteries for electric vehicles in the national standard (Standard No.: GB38031).

[0024] Figure 6 Schematic block diagram of an electric vehicle according to an embodiment of the present application. Please refer to Figure 6, the electric vehicle 10 includes a battery thermal runaway management system 200 and a vehicle control system 14. The battery thermal runaway management system 200 detects multiple temperature values of the battery module 220 and includes a preset temperature critical value, a time threshold, and an alarm temperature threshold. The battery module 220 of the battery thermal runaway management system 200 has battery cells 220A, 220B. One of the multiple temperature sensors 230A, 230B is respectively disposed on the battery cells 220A, 220B. In another embodiment not shown, each of the battery cells 220A, 220B may also be respectively provided with multiple temperature sensors 230A, 230B, and this is not limited thereto. In addition, the battery thermal runaway management system 200 may further include heat-conducting adhesives 240A, 240B, which are respectively disposed between the temperature sensors 230A, 230B and the battery cells 220A, 220B or wrap and protect the temperature sensors 230A, 230B to increase the heat transfer efficiency.

[0025] In this embodiment, the electric vehicle 10 is, for example, an electric car. The battery thermal runaway management system 200 is connected to the vehicle control system 14. The battery cells 220A, 220B supply power to the vehicle control system 14. When the vehicle control system 14 receives a warning signal, it triggers an alarm notification, so that the vehicle control system 14 performs appropriate processing and / or evacuates personnel to reduce hazards.

[0026] In summary, the electric vehicle, the battery thermal runaway management system, and its method of the present application can confirm the battery cell state through three formulas, which can not only improve the accuracy but also reduce misjudgment. Moreover, the electric vehicle, the battery thermal runaway management system, and its method of the present application can monitor battery thermal runaway and give an early warning in an effective and low-cost manner, which not only meets the regulatory requirements but also reduces hazards.

[0027] The above is only a preferred embodiment of the present application and is not used to limit the scope of implementation of the present application. Therefore, all equivalent changes and modifications made according to the shape, structure, features, and spirit described in the claims of the present application should be included within the scope of the claims of the present application.

Claims

1. A battery thermal runaway management system, applied to a battery module, characterized in that, The battery thermal runaway management system includes: a battery cell; a plurality of temperature sensors respectively disposed on the battery module to generate a plurality of temperature sensing signals; and a battery management unit connected to the temperature sensors to receive the plurality of temperature sensing signals and respectively generate respective temperature values according to the plurality of temperature sensing signals, wherein the battery management unit generates a warning signal when the plurality of temperature values satisfy the following formulas: The first formula: T_max >= P1, where T_max is the maximum temperature value among the plurality of temperature values, and P1 is a temperature critical value; The second formula: t > t1, where t is the duration that satisfies the first formula, and t1 is a time threshold; and The third formula: T_max - T_min >= T_threshold, where T_min is the minimum temperature value among the plurality of temperature values, and T_threshold is an alarm temperature threshold.

2. The battery thermal runaway management system according to claim 1, wherein The temperature critical value is greater than the operating temperature of the battery cell and less than the thermal runaway temperature of the battery cell, and the time threshold is the duration after the maximum temperature value reaches the temperature critical value.

3. An electric vehicle, characterized in that, It includes: a battery thermal runaway management system that detects a plurality of temperature values of a battery module and includes a preset temperature critical value, a time threshold, and an alarm temperature threshold, wherein when the maximum temperature value among the plurality of temperature values is greater than the temperature critical value, and the duration that the maximum temperature value is greater than the temperature critical value exceeds the time threshold, and the temperature difference between the minimum temperature value and the maximum temperature value among the plurality of temperature values is greater than the alarm temperature threshold, a warning signal is generated; and a vehicle control system connected to the battery thermal runaway management system, and when the vehicle control system receives the warning signal, an alarm notification is triggered.

4. A battery thermal runaway management method is applied to a battery management unit to manage a battery module, characterized in that, It includes: disposing a plurality of temperature sensors on the battery module to generate a plurality of temperature values; providing a temperature critical value, a time threshold, and an alarm temperature threshold corresponding to the battery module; obtaining the maximum temperature value and the minimum temperature value among the plurality of temperature values; calculating the temperature difference between the minimum temperature value and the maximum temperature value; and when the duration that the maximum temperature value is greater than the temperature critical value exceeds the time threshold, and the temperature difference is greater than the alarm temperature threshold, generating a warning signal.

5. The battery thermal runaway management method according to claim 4, wherein The temperature critical value corresponding to the battery module is obtained by a fluid simulation program, and the steps include: simulating to obtain the operating temperature and the thermal runaway temperature of the battery cell in the battery module; simulating and calculating to obtain at least 5 minutes of simulation temperature before the battery cell reaches the thermal runaway temperature fastest as the final warning temperature value; and setting the temperature critical value according to the final warning temperature value, the operating temperature, and the working condition of the battery module, wherein the temperature critical value is less than the final warning temperature value and greater than the operating temperature.

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