Thermal runaway protection system and method of battery, battery pack and vehicle

Abstract

The invention provides a thermal runaway protection system and a thermal runaway protection method of a battery and a battery pack. The thermal runaway protection system comprises a detection module which is configured to detect the state information of the battery in real time; the judgment module is configured to determine that the battery is in a thermal runaway state based on the state information and generate a fault signal; and the execution module is configured to switch off a main loop of the battery in response to the fault signal. The thermal runaway protection system is arranged in the battery, whether the battery is in the thermal runaway state or not can be automatically detected in real time, the main loop of the battery is directly cut off when the battery is in the thermal runaway state, the thermal runaway protection time is shortened, passengers can obtain more escape time, and the safety and reliability of a vehicle are improved.

Description

Technical Field

[0001] The present invention relates to the field of vehicles, and more particularly to the field of battery systems for vehicles. More specifically, the present invention relates to a thermal runaway protection system for a battery, a method for protecting a battery from thermal runaway, a battery pack applying the thermal runaway protection system, and a vehicle applying the thermal runaway protection system or a vehicle using the method for protecting a battery from thermal runaway. Background Art

[0002] In recent years, with the increasing demand for energy conservation and environmental protection, new energy has been widely used in various fields, especially in the field of vehicles. Such vehicles mainly use power batteries as the main energy source, so the reliability and safety of power batteries have a direct impact on the performance and driving safety of the whole vehicle.

[0003] When internal faults occur in a power battery during operation due to overcharging, over-discharging, short circuit, high temperature, collision, etc., it may cause the chemical reaction inside the battery to get out of control, generate a large amount of heat, and trigger thermal runaway. In this case, the temperature of the battery may rise rapidly, even causing a fire or explosion.

[0004] Therefore, how to achieve rapid thermal runaway protection for the battery to leave enough escape time for passengers is an urgent problem to be solved. Summary of the Invention

[0005] The object of the present invention is to solve the problems existing in the above-mentioned prior art, and provide a thermal runaway protection system for a battery, which improves the thermal runaway protection process of the battery in a cost-effective and reliable manner.

[0006] To this end, according to one aspect of the present invention, there is provided a thermal runaway protection system for a battery. The thermal runaway protection system includes: a detection module configured to detect the state information of the battery in real time; a judgment module configured to determine that the battery is in a thermal runaway state based on the state information and generate a fault signal; and an execution module configured to disconnect the main circuit of the battery in response to the fault signal.

[0007] According to the above technical concept, the present invention may further include any one or more of the following optional forms.

[0008] In some optional forms, the state information includes the current passing through the battery, and the judgment module is configured to generate a fault signal based on the detected current being greater than a preset threshold.

[0009] In some optional forms, the execution module includes a trigger unit and a cut-off unit, and the trigger unit is configured to trigger an explosive reaction based on the fault signal and drive the cut-off unit to disconnect the main circuit of the battery.

[0010] In some optional forms, the detection module, the judgment module, and the execution module are integrated into one body.

[0011] In some optional forms, the detection module is a Hall chip.

[0012] In some optional forms, the detection module is a shunt module.

[0013] In some optional forms, the execution module is an active fuse.

[0014] According to another embodiment of the present invention, a method for thermal runaway protection of a battery is provided. The thermal runaway protection method includes: real-time detecting the state information of the battery; determining that the battery is in a thermal runaway state based on the state information and generating a fault signal; and disconnecting the main circuit of the battery in response to the fault signal.

[0015] In some optional forms, determining that the battery is in a thermal runaway state based on the state information and generating a fault signal includes: generating the fault signal based on the detected current passing through the battery being greater than a preset threshold.

[0016] According to another embodiment of the present invention, a battery pack is provided, and the above-mentioned thermal runaway protection system of the battery is provided inside the battery pack.

[0017] According to another embodiment of the present invention, a vehicle is provided. The vehicle includes the above-mentioned thermal runaway protection system of the battery or the above-mentioned battery pack, or the vehicle uses the above-mentioned thermal runaway protection method of the battery to perform thermal runaway protection on the vehicle's battery.

[0018] By setting a thermal runaway protection system in the battery, the present invention can self-detect in real time whether the battery is in a thermal runaway state, and directly cut off the main circuit of the battery when the battery is in a thermal runaway state, reducing the time for thermal runaway protection, enabling passengers to obtain more escape time, and improving the safety and reliability of the vehicle. Description of the Drawings

[0019] Other features and advantages of the present invention will be better understood through the following optional embodiments described in detail in conjunction with the drawings, where:

[0020] Figure 1 A schematic diagram of a thermal runaway protection system of a battery according to an embodiment of the present invention is shown;

[0021] Figure 2 A schematic diagram of a battery pack according to an embodiment of the present invention is shown; and

[0022] Figure 3Schematically shows a flow chart of a method for preventing thermal runaway of a battery according to an embodiment of the present invention. Detailed Embodiments

[0023] The implementation and use of the embodiments are discussed in detail below. However, it should be understood that the specific embodiments discussed are merely exemplary illustrations of specific ways of implementing and using the present invention, and do not limit the scope of the present invention.

[0024] In addition, the flow charts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of the methods and systems according to various embodiments of the present invention. It should be noted that the functions marked in the blocks may also occur in a different order than that marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, or they may sometimes be executed in the reverse order, depending on the functions involved.

[0025] Battery thermal runaway generally refers to the situation where the heat generated inside the battery is much greater than the heat dissipated, resulting in a sharp rise in the battery temperature, thereby causing battery failure. The inventors found that currently, when detecting battery thermal runaway, usually the battery management system (BMS) or the vehicle controller unit (VCU), etc., send instructions to the high-voltage relay of the battery to perform thermal runaway protection actions. Since the BMS or VCU needs to process various signals during vehicle operation, the time for the BMS or VCU to send control instructions to the high-voltage relay is relatively long, for example, more than 10 ms, and the escape time left for passengers will be relatively short. In addition, when the high-voltage relay performs thermal runaway protection actions, corrosion may occur on the two contact surfaces of the high-voltage relay when it remains closed, resulting in the relay being unable to work properly.

[0026] Refer to Figure 1 , Figure 1 Shows a schematic diagram of a battery thermal runaway protection system according to an embodiment of the present invention.

[0027] The battery thermal runaway protection system 100 according to the present invention generally includes a detection module 110, a judgment module 120, and an execution module 130. The detection module 110 is used to detect the state information of the battery in real time by itself. The judgment module 120 receives the state information from the detection module 110, determines whether the battery is in a thermal runaway state based on this state information, and generates a fault signal when the battery is in a thermal runaway state. The execution module 130 receives the fault signal from the judgment module 120, and disconnects the main circuit of the battery in response to this fault signal to perform thermal runaway protection actions.

[0028] In this way, the thermal runaway protection system 100 of the battery according to the present invention performs protection actions against thermal runaway by detecting that the state information of the battery reaches the thermal runaway state, without transmitting the detected state information to other controllers such as BMS or VCU, reducing the response time of the system and enabling passengers to obtain more escape time.

[0029] In some embodiments, the state information of the battery may include the current passing through the battery. In this case, the determination module 120 may generate a fault signal based on the detected current being greater than a preset threshold. In some embodiments, the preset threshold may be, for example, 1000 A. It can be understood that the preset threshold is not limited thereto and can be adjusted according to system requirements. Thus, the thermal runaway protection system 100 of the present invention uses the preset threshold of the battery current as the action trigger signal for the execution module 130, so that the action of cutting off the circuit can be performed when the current of the battery exceeds the preset threshold. Additionally, the state information of the battery is not limited thereto and may also include, for example, the voltage, temperature, etc. of the battery as required. In this case, the determination module 120 may determine whether the battery is in a thermal runaway state based on the detected voltage, temperature, temperature gradient, etc. to generate a fault signal. Here, the preset threshold of the voltage may be, for example, 800 V, the preset threshold of the temperature may be, for example, 500 °C, and the preset threshold of the temperature gradient may be, for example, 10 °C / min.

[0030] In some embodiments, the detection module 110 may be a Hall chip. A Hall chip is a silicon chip or integrated circuit containing a Hall sensor to facilitate the integration of the Hall sensor into an electronic system. The Hall chip measures the current by detecting the Hall effect in a magnetic field for non-contact measurement, thereby avoiding direct contact with the circuit and reducing resistance, power consumption, and heat loss, etc. Additionally, the Hall chip has a fast response time and can promptly respond to the current passing through the battery, resulting in higher detection accuracy.

[0031] Alternatively, the detection module 110 may also be a shunt module. The shunt module may be a resistive element. When current passes through the shunt module, a voltage will be generated across the two ends of the shunt module, and this voltage is proportional to the current. Therefore, the current can be obtained by measuring the generated voltage. The shunt module can provide high accuracy due to its simple structure. Thus, when the current detection accuracy required by the thermal runaway protection system 100 is relatively high, the shunt module can be used for detection.

[0032] In some embodiments, the execution module 130 may include a trigger unit 131 and a cut-off unit 132. When the current of the battery exceeds a preset threshold, the trigger unit 131 will receive a fault signal from the judgment module 120. At this time, the internal pressure of the trigger unit 131 will increase. When the internal pressure increases to a certain extent, a part or the whole of the trigger unit 131 inside may have an explosion reaction. This explosion reaction will drive the cut-off unit 132 to move, thereby disconnecting the main circuit of the battery. In this way, the thermal runaway state of the battery can be responded to more quickly, the circuit can be quickly cut off, and the overall safety of the battery system can be improved.

[0033] Additionally, the execution module 130 can be an active fuse (Pyro fuse). In this case, the trigger unit 131 can be a starter, and the cut-off unit can be a piston device. Specifically, the active fuse can be arranged in the main circuit of the battery. When the active fuse receives a fault signal, the starter will ignite the explosive fuel inside it, release gas, and the gas drives the piston device to move quickly, cutting off the copper busbar of the active fuse, thereby disconnecting the main circuit of the battery.

[0034] In some embodiments, the detection module 110, the judgment module 120, and the execution module 130 can be integrated into one body. That is to say, the detection module 110, the judgment module 120, and the execution module 130 can be integrated in one module. In this way, it is convenient to integrate the thermal runaway protection system 100 into the main circuit of the battery, and the actions of judging whether the battery is in a thermal runaway state and disconnecting the main circuit of the battery can be completed within one module, without additional signal transmission and processing steps, and decisions can be made and thermal runaway protection actions can be executed more quickly, improving the response speed of the thermal runaway protection system 100.

[0035] Referring to Figure 2 , Figure 2 FIG. shows a schematic diagram of a battery pack according to an embodiment of the present invention.

[0036] The thermal runaway protection system 100 according to the present invention can be arranged in the battery pack 200. Specifically, in this embodiment, the battery pack 200 includes a first battery pack 210 and a second battery pack 220 spaced apart in the left-right direction in Figure 2 , the first battery pack 210 and the second battery pack 220 both include 6 battery modules, and each battery module is provided with a plurality of battery cells, such as 5 battery cells. The thermal runaway protection system 100 can be arranged between the battery module 6 and the battery module 7 to perform thermal runaway protection actions. It can be understood that the arrangement method of the thermal runaway protection system 100 is not limited to this, and it can be arranged at any position in the battery pack 200 that needs to be protected as required.

[0037] Referring toFigure 3 , Figure 3 shows a schematic flowchart of a method for preventing thermal runaway of a battery according to an embodiment of the present invention.

[0038] The method for preventing thermal runaway of a battery according to an embodiment of the present invention may include the following steps.

[0039] Step S101: Detect the status information of the battery in real time.

[0040] Step S102: Determine whether the battery is in a thermal runaway state based on the status information, and generate a fault signal when the battery is in a thermal runaway state.

[0041] Step S103: Disconnect the main circuit of the battery in response to the generated fault signal.

[0042] In this way, when the battery is in a thermal runaway state, the main circuit of the battery can be directly cut off, reducing the time for thermal runaway protection, enabling passengers to obtain more escape time, and improving the safety and reliability of the vehicle.

[0043] The present invention places a thermal runaway protection system between two battery packs of the battery pack. In the case of short circuit or creepage caused by high voltage, etc., the main circuit of the battery pack can be quickly cut off. Through this quick cut-off action, when the thermal behavior of the first battery pack has got out of control, the risk of short circuit of the second battery pack can also be reduced. In addition, the present invention uses an active fuse for the cut-off action. The piston device of the active fuse can cut off the copper busbar within 2 ms, and the overall response time of the thermal runaway protection system can be within 3 ms, so that passengers can be better protected.

[0044] It should be understood that the embodiments shown in the figures only show the optional configuration modes of the thermal runaway protection system of the battery according to the present invention. However, they are only illustrative and not restrictive. Without departing from the spirit and scope of the present invention, other configuration modes may also be adopted.

[0045] The technical content and technical features of the present invention have been disclosed above. However, it can be understood that under the creative concept of the present invention, those skilled in the art can make various changes and improvements to the above disclosed concept, but all belong to the protection scope of the present invention. The description of the above embodiments is illustrative rather than restrictive, and the protection scope of the present invention is determined by the claims.

Claims

1. A thermal runaway protection system for a battery, characterized in that The thermal runaway protection system (100) includes: A detection module (110) configured to detect the state information of the battery in real time; A judgment module (120) configured to determine that the battery is in a thermal runaway state based on the state information and generate a fault signal; An execution module (130) configured to disconnect the main circuit of the battery in response to the fault signal.

2. The thermal runaway protection system for the battery according to claim 1, characterized in that, The state information includes the current passing through the battery, and the judgment module (120) is configured to generate the fault signal based on the detected current being greater than a preset threshold.

3. The thermal runaway protection system of the battery according to claim 1, characterized in that The execution module (130) includes a trigger unit (131) and a cut-off unit (132), and the trigger unit (131) is configured to trigger an explosion reaction based on the fault signal and drive the cut-off unit (132) to disconnect the main circuit of the battery.

4. The thermal runaway protection system for the battery according to claim 1, characterized in that, The detection module (110), the judgment module (120), and the execution module (130) are integrated into one body.

5. The thermal runaway protection system of the battery according to any one of claims 1 to 4, characterized in that The detection module (110) is a Hall chip.

6. The thermal runaway protection system for a battery according to any one of claims 1 to 4, characterized in that, The detection module (110) is a shunt module.

7. The thermal runaway protection system for a battery according to any one of claims 1 to 4, characterized in that, The execution module (130) is an active fuse.

8. A method for preventing thermal runaway of a battery, characterized in that, The thermal runaway protection method includes: Detecting the state information of the battery in real time (S101); Determining that the battery is in a thermal runaway state based on the state information and generating a fault signal (S102); Disconnecting the main circuit of the battery in response to the fault signal (S103).

9. The thermal runaway protection method for the battery according to claim 8, wherein, Determining that the battery is in a thermal runaway state based on the state information and generating a fault signal includes: generating the fault signal based on the detected current passing through the battery being greater than a preset threshold.

10. A battery pack, characterized in that, The battery pack (200) is provided with the thermal runaway protection system of the battery according to any one of claims 1 to 7.

11. A vehicle, characterized in that, The vehicle includes the thermal runaway protection system of the battery according to any one of claims 1 to 7 or the battery pack according to claim 10, or the vehicle uses the thermal runaway protection method of the battery according to any one of claims 8 to 9 to protect the battery of the vehicle from thermal runaway.

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