Emergency driving system for coping with thermal runaway and vehicle

Abstract

An emergency driving system for coping with thermal runaway comprises a power battery pack and a battery management system BMS, a plurality of battery modules connected in series are arranged in the power battery pack, any battery module comprises a battery cell group, an isolation cabin and an emergency contactor, the battery cell group and the emergency contactor are arranged in parallel, and the isolation cabin is arranged in the battery cell group. The battery module comprises a battery cell group and a battery management system BMS, the battery cell group is wrapped by the isolation cabin, the isolation cabin is used for isolating the battery cell group in the isolation cabin from any other battery module so as to delay thermal runaway propagation between the battery modules, the battery management system BMS is electrically connected with the battery modules, and the battery management system BMS is used for monitoring whether the battery modules are in thermal runaway or not. And the BMS is also used for switching on the emergency contactor when the battery module is in thermal runaway so as to short-circuit the battery cell group.

Description

Technical Field

[0001] The utility model relates to the technical field of emergency driving systems, and in particular to an emergency driving system and a vehicle for coping with thermal runaway. Background Art

[0002] Ternary lithium-ion power batteries have high specific energy density and good low-temperature characteristics and have been widely used in the field of new energy vehicles. With the increase in the number of new energy vehicles, a considerable number of new energy vehicle spontaneous combustion incidents occur every year, and many new energy vehicle fire accidents are related to thermal runaway of power batteries.

[0003] Thermal runaway of power batteries refers to overheating, fire, explosion and other phenomena caused by a sharp change in the temperature rise rate of the battery due to the chain reaction of heat release from single batteries. The causes of thermal runaway usually include thermal runaway triggered by overheating, thermal runaway triggered by overcharging, thermal runaway triggered by internal short circuit, thermal runaway triggered by mechanical collision, etc. When thermal runaway occurs, the vehicle's battery management system usually controls the high-voltage contactor to disconnect immediately to prevent the battery pack from exploding and protect the safety of the vehicle. However, once the high-voltage line is cut off, the vehicle will lose power. Under complex conditions such as high-speed driving, the vehicle is prone to rear-end collision. Under conditions of climbing and hill climbing, it is also easy to block the lane, causing traffic accidents and secondary injuries. Summary of the invention

[0004] The utility model provides an emergency driving system for coping with thermal runaway, comprising a power battery pack and a battery management system BMS, wherein a plurality of battery modules connected in series are arranged in the power battery pack, and any of the battery modules comprises a cell group, an isolation compartment and an emergency contactor, the cell group and the emergency contactor are arranged in parallel, the isolation compartment wraps the cell group, and the isolation compartment is used to isolate the cell group therein from any other battery module to delay the propagation of thermal runaway between the battery modules, the battery management system BMS is electrically connected to the battery module, the battery management system BMS is used to monitor whether the battery module is in thermal runaway, and the battery management system BMS is also used to connect the emergency contactor to short-circuit the cell group when the battery module is in thermal runaway.

[0005] Furthermore, the isolation cabin is made of ceramic fiber.

[0006] Furthermore, the power battery pack also includes a main contactor and a pre-charging circuit. The main contactor is connected in series with the battery module in the power battery pack, and the pre-charging circuit is arranged in parallel with the main contactor. The main contactor is used to control whether the power battery pack is connected to the high-voltage line. The pre-charging circuit is used to short-circuit the main contactor when the power battery pack is connected to the high-voltage line to reduce the current shock to the power battery pack.

[0007] Furthermore, the main contactor includes a positive contactor and a negative contactor, the battery module is connected in series between the positive contactor and the negative contactor, and the pre-charging circuit is arranged in parallel with the positive contactor.

[0008] Furthermore, the pre-charging circuit includes a pre-charging resistor and a pre-charging contactor, the pre-charging resistor and the pre-charging contactor are arranged in series, and the pre-charging contactor is used to control whether the pre-charging circuit is connected to the high-voltage line.

[0009] Furthermore, the battery management system BMS also includes a detection module installed in the power battery pack, and the detection module is used to detect the temperature, voltage and pressure of the battery module.

[0010] Furthermore, the detection module includes a temperature sensor for detecting the temperature of the battery module, the temperature sensor is integrated in the battery module, the temperature sensor is electrically connected to the battery management system BMS, and the temperature sensor is used to alarm the detection module when abnormal temperature of the battery module is detected.

[0011] Furthermore, the detection module includes a pressure sensor for detecting the pressure of the battery module, the pressure sensor is integrated in the battery module, the pressure sensor is electrically connected to the battery management system BMS, and the pressure sensor is used to alarm the detection module when abnormal pressure of the battery module is detected.

[0012] Furthermore, the detection module includes a voltage sensor for detecting the voltage of the battery module, the voltage sensor is electrically connected to the battery cells in the battery cell group to detect the voltage of the battery cell group, the voltage sensor is electrically connected to the battery management system BMS, and the voltage sensor is used to alarm the detection module when an abnormal voltage of the battery cell group is detected.

[0013] Furthermore, the utility model also includes a vehicle, which includes the aforementioned emergency driving system for coping with thermal runaway.

[0014] The emergency driving system for dealing with thermal runaway provided by the utility model provides a feasible solution for emergency driving by means of an isolation cabin wrapped outside the battery pack and an emergency contactor connected in parallel with the battery pack. When thermal runaway occurs, the emergency contactor is turned on to short-circuit the battery module that has thermal runaway, so that the vehicle can drive for a period of time to reach a safe area, thereby ensuring the safety of roads and passengers and avoiding car accidents and secondary injuries. The utility model also prevents thermal runaway from spreading directly to other battery modules through an isolation cabin made of ceramic fiber, thereby improving the overall safety of the power battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of an emergency driving system for coping with thermal runaway provided by the utility model. DETAILED DESCRIPTION

[0016] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the present invention is described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0017] It should be noted that the terms "first", "second", "third", "fourth", etc. in the specification and claims of the utility model are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0018] The utility model provides an emergency driving system for dealing with thermal runaway, which is particularly suitable for new energy vehicles. Figure 1 The emergency driving system for coping with thermal runaway in the utility model includes a power battery pack 1 and a battery management system BMS. A plurality of battery modules 2 connected in series are arranged in the power battery pack 1. Any battery module 2 includes a cell group 3, an isolation compartment 4 and an emergency contactor 5. The cell group 3 and the emergency contactor 5 are arranged in parallel. The isolation compartment 4 wraps the cell group 3. The isolation compartment 4 is used to isolate the cell group 3 therein from any other battery module 2 to delay the propagation of thermal runaway between the battery modules 2. The battery management system BMS is electrically connected to the battery module 2. The battery management system BMS is used to monitor whether the battery module 2 is in thermal runaway. The battery management system BMS is also used to connect the emergency contactor 5 when the battery module 2 is in thermal runaway to short-circuit the cell group 3. When any battery module 2 experiences thermal runaway, the isolation cabin 4 can prevent the thermal runaway from spreading directly to other battery modules 2 through its own excellent thermal insulation performance. At the same time, the battery management system BMS controls its corresponding emergency contactor 5 to be turned on to short-circuit the battery module 2, temporarily removing the out-of-control battery module 2 from the high-voltage circuit of the power battery pack 1, allowing the vehicle to travel in an emergency for a period of time to reach a safe area, ensuring the safety of the road and passengers. It is easy to understand that the isolation cabin 4 is made of a material with strong heat resistance and low thermal conductivity, preferably ceramic fiber. Please refer to Figure 1 In the present embodiment, a total of eight battery cell groups 3 connected in series, M1 to M8, are provided in the power battery pack 1, which correspond to a total of eight emergency contactors 5, S1 to S8, respectively. The battery cell groups 3 are respectively wrapped and isolated by eight isolation compartments 4, but the emergency contactors 5 are located outside the corresponding isolation compartments 4. In other embodiments, the number of battery modules 2 can be adjusted according to the size of the power battery pack 1 and the actual requirements of the vehicle model, as long as any battery module 2 is ensured to be individually wrapped by the isolation compartment 4.

[0019] Furthermore, the power battery pack 1 in the utility model also includes a main contactor and a pre-charging circuit. The main contactor is connected in series with the battery module 2 in the power battery pack 1. The pre-charging circuit is arranged in parallel with the main contactor. The main contactor is used to control whether the power battery pack 1 is connected to the high-voltage line. The pre-charging circuit is used to short-circuit the main contactor when the power battery pack 1 is connected to the high-voltage line to reduce the current impact on the power battery pack 1. Specifically, the main contactor includes a positive contactor 61 and a negative contactor 62. The battery module 2 is connected in series between the positive contactor 61 and the negative contactor 62. The pre-charging circuit is arranged in parallel with the positive contactor 61; the pre-charging circuit includes a pre-charging resistor 71 and a pre-charging contactor 72. The pre-charging resistor 71 and the pre-charging contactor 72 are arranged in series. The pre-charging contactor 72 is used to control whether the pre-charging circuit is connected to the high-voltage line. Before the vehicle is ready to charge the capacitor with high voltage, the battery management system BMS controls the pre-charge contactor 72 of the pre-charge circuit to close and the positive contactor 61 to open. Since the pre-charge resistor 71 is provided in the pre-charge circuit, the current impact on the power battery pack 1 can be reduced to a certain extent. When the capacitor charging reaches the set threshold, the battery management system BMS controls the pre-charge contactor 72 to open and the positive contactor 61 to close, that is, the pre-charge circuit is disconnected from the main contactor and the circuit where the battery module 2 is located, and the power battery pack 1 works normally. In addition, when thermal runaway occurs, that is, when the thermal runaway battery module 2 is disconnected and the emergency driving system is enabled, the battery management system BMS controls the pre-charge contactor 72 of the pre-charge circuit to close and the positive contactor 61 to open. At this time, the pre-charge circuit reduces the current impact on the power battery pack 1 through the pre-charge resistor 71 therein, which plays a role in maintaining the stability of the emergency driving system.

[0020] Furthermore, the battery management system BMS also includes a detection module installed in the power battery pack 1, and the detection module is used to detect the temperature, voltage and pressure of the battery module 2. Specifically, the detection module includes a temperature sensor for detecting the temperature of the battery module 2, a pressure sensor for detecting the pressure of the battery module 2, and a voltage sensor for detecting the voltage of the battery module 2. The temperature sensor is integrated in the battery module 2, and the temperature sensor is electrically connected to the battery management system BMS. The temperature sensor is used to alarm the detection module when the temperature of the battery module 2 is detected to be abnormal; the pressure sensor is integrated in the battery module 2, and the pressure sensor is electrically connected to the battery management system BMS. The pressure sensor is used to alarm the detection module when the pressure of the battery module 2 is detected to be abnormal; the voltage sensor is electrically connected to the battery cells in the battery cell group 3 to detect the voltage of the battery cell group 3, and the voltage sensor is electrically connected to the battery management system BMS. The voltage sensor is used to alarm the detection module when the voltage of the battery cell group 3 is detected to be abnormal. In this embodiment, for the sake of system simplicity and economic cost, at least one temperature sensor is provided in any battery module 2; the voltage sensor monitors the voltage of all battery cells in the battery cell group 3, that is, at least one voltage sensor is provided in any battery module 2, and the voltage sensor detects the battery cells of the corresponding battery cell group 3; the pressure sensor monitors the pressure of the corresponding battery module 2, that is, at least one pressure sensor is provided in any battery module 2.

[0021] Furthermore, the utility model also includes a vehicle, which includes the aforementioned emergency driving system for coping with thermal runaway.

[0022] In summary, the emergency driving system for dealing with thermal runaway of the utility model provides a feasible solution for emergency driving by wrapping the isolation cabin outside the battery pack and the emergency contactor connected in parallel with the battery pack. When thermal runaway occurs, the emergency contactor is turned on to short-circuit the battery module that has thermal runaway, so that the vehicle can drive for a period of time to reach a safe area, ensuring the safety of roads and passengers, and avoiding traffic accidents and secondary injuries. The utility model also prevents thermal runaway from spreading directly to other battery modules through the isolation cabin made of ceramic fiber, thereby improving the overall safety of the power battery pack.

[0023] The above are only specific implementations of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. An emergency driving system for coping with thermal runaway, characterized in that: The invention comprises a power battery pack (1) and a battery management system (BMS), wherein a plurality of battery modules (2) connected in series are arranged in the power battery pack (1), and any of the battery modules (2) comprises a battery cell group (3), an isolation compartment (4) and an emergency contactor (5), wherein the battery cell group (3) and the emergency contactor (5) are arranged in parallel, and the isolation compartment (4) encloses the battery cell group (3), and the isolation compartment (4) is used to isolate the battery cell group (3) therein from any other battery module (2) so as to delay the propagation of thermal runaway between the battery modules (2), and the battery management system (BMS) is electrically connected to the battery module (2), and the battery management system (BMS) is used to monitor whether the battery module (2) is in thermal runaway, and the battery management system (BMS) is also used to connect the emergency contactor (5) when the battery module (2) is in thermal runaway so as to short-circuit the battery cell group (3).

2. The emergency driving system for coping with thermal runaway according to claim 1, characterized in that: The isolation cabin (4) is made of ceramic fiber.

3. The emergency driving system for coping with thermal runaway according to claim 1, characterized in that: The power battery pack (1) further comprises a main contactor and a pre-charging circuit. The main contactor is connected in series with the battery module (2) in the power battery pack (1). The pre-charging circuit is arranged in parallel with the main contactor. The main contactor is used to control whether the power battery pack (1) is connected to the high-voltage line. The pre-charging circuit is used to short-circuit the main contactor when the power battery pack (1) is connected to the high-voltage line, so as to reduce the current impact on the power battery pack (1).

4. The emergency driving system for coping with thermal runaway according to claim 3, characterized in that: The main contactor comprises a positive contactor (61) and a negative contactor (62), the battery module (2) is connected in series between the positive contactor (61) and the negative contactor (62), and the pre-charging circuit is arranged in parallel with the positive contactor (61).

5. The emergency driving system for coping with thermal runaway according to claim 3, characterized in that: The pre-charging circuit comprises a pre-charging resistor (71) and a pre-charging contactor (72), wherein the pre-charging resistor (71) and the pre-charging contactor (72) are arranged in series, and the pre-charging contactor (72) is used to control whether the pre-charging circuit is connected to the high-voltage line.

6. The emergency driving system for coping with thermal runaway according to claim 1, characterized in that: The battery management system BMS also includes a detection module installed in the power battery pack (1), and the detection module is used to detect the temperature, voltage and pressure of the battery module (2).

7. The emergency driving system for coping with thermal runaway according to claim 6, characterized in that: The detection module comprises a temperature sensor for detecting the temperature of the battery module (2); the temperature sensor is integrated in the battery module (2); the temperature sensor is electrically connected to the battery management system BMS; the temperature sensor is used to send an alarm to the detection module when an abnormal temperature of the battery module (2) is detected.

8. The emergency driving system for coping with thermal runaway according to claim 6, characterized in that: The detection module comprises a pressure sensor for detecting the pressure of the battery module (2); the pressure sensor is integrated in the battery module (2); the pressure sensor is electrically connected to the battery management system BMS; the pressure sensor is used to alarm the detection module when an abnormal pressure in the battery module (2) is detected.

9. The emergency driving system for coping with thermal runaway according to claim 6, characterized in that: The detection module comprises a voltage sensor for detecting the voltage of the battery module (2); the voltage sensor is electrically connected to the battery cells in the battery cell group (3) to detect the voltage of the battery cell group (3); the voltage sensor is electrically connected to the battery management system BMS; the voltage sensor is used to alarm the detection module when an abnormal voltage of the battery cell group (3) is detected.

10. A vehicle, characterized in that: It comprises the emergency driving system for coping with thermal runaway as claimed in any one of claims 1 to 9.

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