Thermal runaway protection device and battery pack

Abstract

The utility model provides a thermal runaway protection device and a battery pack. The thermal runaway protection device is used for thermal runaway protection of the battery pack, and the battery pack comprises a first anti-explosion valve and a second anti-explosion valve. The thermal runaway protection device comprises an inflation assembly, an exhaust assembly and a control assembly. The inflation assembly is arranged on the first anti-explosion valve, is communicated with the interior of the battery pack and is used for filling inert gas into the battery pack; the exhaust assembly is arranged on the second anti-explosion valve and is communicated with the interior of the battery pack; the control assembly is electrically connected with the air inflation assembly and the air exhaust assembly and used for controlling starting and stopping of the air inflation assembly and the air exhaust assembly. According to the utility model, open fire after thermal runaway of the battery pack can be avoided, and the thermal runaway protection device has the advantages of good thermal runaway protection performance and high electrical safety.

Description

Technical Field

[0001] The utility model relates to the technical field of new energy vehicles, in particular to a thermal runaway protection device.

[0002] The utility model also relates to a battery pack including the above thermal runaway protection device. Background Art

[0003] As an energy storage component of new energy vehicles, the electrical safety problem of the battery pack will directly affect the driving safety and has always been concerned by all parties. With the improvement of production technology and manufacturing level, the probability of thermal runaway accidents of battery packs has gradually decreased in recent years. However, objectively, there is still a possibility of thermal runaway accidents in the battery pack. When the battery pack undergoes thermal runaway, it is very likely to cause serious consequences such as fire and explosion. Therefore, the thermal runaway control device and technology of the battery pack are an indispensable part of ensuring the electrical safety of the battery pack.

[0004] At present, the conventional thermal runaway technology of the battery pack is to control the open fire caused by overheating of the battery cells inside the battery pack to achieve the effect that no open fire is visible outside the battery pack. This thermal runaway control method not only puts higher requirements on the performance of the battery pack shell, resulting in an increase in the manufacturing cost of the battery pack, but also inevitably leads to the appearance of open fire. The potential safety hazards, economic losses and environmental pollution caused by the combustion of open fire are irreversible.

[0005] It can be known from the above prior art that the existing thermal runaway control technology adopted by new energy vehicle battery packs cannot avoid the appearance of open fire, making the battery pack still lack in electrical safety. Summary of the Utility Model

[0006] In view of this, the utility model aims to provide a thermal runaway protection device and a battery pack, which can avoid the appearance of open fire after the thermal runaway of the battery pack and have the advantages of good thermal runaway protection performance and high electrical safety.

[0007] To achieve the above object, the technical solution of the utility model is realized as follows:

[0008] A thermal runaway protection device of the utility model includes an inflation component, which is arranged on the first explosion-proof valve and communicated with the inside of the battery pack for filling inert gas into the battery pack;

[0009] An exhaust component, which is arranged on the second explosion-proof valve and communicated with the inside of the battery pack;

[0010] A control component, which is electrically connected with the inflation component and the exhaust component for controlling the start and stop of the inflation component and the exhaust component.

[0011] Further, the inflation assembly includes a storage tank filled with compressed inert gas;

[0012] An inflation pipe, one end of which is communicated with the storage tank and the other end of which is communicated with the first explosion-proof valve;

[0013] An inflation pump is arranged on the inflation pipe and is used for inflating the gas in the inflation pipe into the battery pack;

[0014] An inflation valve is arranged on the inflation pipe and is used for controlling the on-off of the air flow in the inflation pipe.

[0015] Further, the exhaust assembly includes an exhaust pipe, one end of which is communicated with the second explosion-proof valve;

[0016] An exhaust pump is arranged on the exhaust pipe and is used for exhausting the gas in the battery pack through the exhaust pipe;

[0017] An exhaust valve is arranged on the exhaust pipe and is used for controlling the on-off of the air flow in the exhaust pipe.

[0018] Further, the control assembly includes an oxygen concentration sensor arranged in the battery pack and used for detecting the oxygen concentration in the battery pack;

[0019] A control panel is electrically connected to the oxygen concentration sensor, the inflation assembly and the exhaust assembly and is used for controlling the start and stop of the inflation assembly and the exhaust assembly.

[0020] Further, the exhaust assembly further includes a filter arranged at one end of the exhaust pipe far away from the battery pack.

[0021] Further, a pressure sensor is arranged on the storage tank, and the pressure sensor is electrically connected to the control panel. Compared with the prior art, the present utility model has the following advantages:

[0022] The thermal runaway protection device of the present utility model includes an inflation assembly, an exhaust assembly and a control assembly. When the control assembly detects that there is oxygen in the environment inside the battery pack and there is a risk of open fire after the battery pack undergoes thermal runaway, the inflation assembly and the exhaust assembly will start to operate under the control of the control assembly. The inflation assembly will inflate nitrogen or other flame-retardant inert gas into the battery pack. The exhaust assembly can exhaust the original oxygen-containing gas in the battery pack to ensure the balance of the internal and external air pressures of the battery pack. When most or all of the oxygen-containing gas in the battery pack is replaced by inert gas, the internal environment no longer meets the conditions for open fire combustion. Even if the battery pack undergoes thermal runaway, there will be no open fire combustion or even explosion, thus achieving the invention purpose of avoiding open fire after the battery pack undergoes thermal runaway, and having the advantages of good thermal runaway protection performance and high electrical safety.

[0023] In addition, by setting the inflation assembly as a combination of a storage tank, an inflation pipe, an inflation pump, and an inflation valve, the storage tank therein can serve as a container for storing inert gas; the inflation pipe can serve as a passage for the inert gas to enter the battery pack from the storage tank; the inflation pump can provide power for the directional movement of the inert gas; the inflation valve can be used to control the on-off of the air flow in the inflation pipe, and cooperate with the inflation pump to enable the inflation assembly to fill the inside of the battery pack with inert gas under the control of the control assembly. By providing a pressure sensor on the storage tank, it can be used to detect the gas pressure in the storage tank, thereby prompting the user of the content of the remaining inert gas in the storage tank, facilitating the user to refill the storage tank.

[0024] Secondly, by setting the exhaust assembly as a combination of an exhaust pipe, an exhaust pump, and an exhaust valve. The exhaust pipe therein can serve as a passage for discharging the gas of the battery pack; the exhaust pump can generate a negative pressure under the control of the control assembly to assist the gas inside the battery pack to be discharged along the exhaust pipe; the exhaust valve can be opened when the pressure reaches a certain value, enabling the exhaust pipe to have a one-way conduction function.

[0025] Furthermore, by setting the control assembly as a combination of an oxygen concentration sensor and a control panel, after the control panel receives the detection signal from the oxygen concentration sensor, it controls the inflation assembly and the exhaust assembly to start operating until the oxygen concentration inside the battery pack drops to a preset critical value where an open flame cannot be generated, and then controls the inflation assembly and the exhaust assembly to stop operating.

[0026] In addition, the present utility model also proposes a battery pack provided with the above-mentioned thermal runaway protection device.

[0027] The battery pack described in the present utility model includes a first explosion-proof valve and a second explosion-proof valve. In addition, it further includes a thermal runaway protection device, adopting the thermal runaway protection device as described above.

[0028] A battery management system for controlling the charging and discharging of the battery pack.

[0029] Further, the first explosion-proof valve and the second explosion-proof valve are arranged on two mutually parallel sides of the battery pack.

[0030] Further, the battery management system is electrically connected to the oxygen concentration sensor.

[0031] Further, the battery management system is electrically connected to the pressure sensor.

[0032] For the battery pack described in the present utility model, the first explosion-proof valve and the second explosion-proof valve are both pressure valves. By providing pressure valves on the outer shell of the battery pack, when the pressure inside the battery pack reaches a certain value, the first explosion-proof valve and the second explosion-proof valve open to connect the inside of the battery pack with the outside world, thereby playing a role in explosion-proof pressure relief. By providing a battery management system on the battery pack, the battery management system can detect and control the charging and discharging states of the battery pack, and can avoid problems such as shortened lifespan or electrical safety issues caused by overcharging or over-discharging of the battery cells.

[0033] Secondly, by respectively arranging the first explosion-proof valve and the second explosion-proof valve on two parallel sides of the outer shell of the battery pack, the inflation assembly and the exhaust assembly can be placed at both ends of the outer shell of the battery pack. This improves the completeness of replacing the oxygen-containing gas with inert gas inside the battery pack by the thermal runaway protection device, further reduces the oxygen content in the battery pack, and thus achieves the invention purpose of improving electrical safety.

[0034] Furthermore, by providing an electrical connection structure between the oxygen concentration sensor and the battery management system, the oxygen concentration value inside the battery pack can be directly transmitted to the vehicle computer through the battery management system and displayed. This facilitates the user to master the state of the battery pack. By providing an electrical connection structure between the pressure sensor and the battery management system, the remaining gas pressure value in the storage tank can be directly transmitted to the vehicle computer through the battery management system and displayed. This facilitates the user to master the remaining gas quantity in the storage tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings forming a part of the present utility model are used to provide a further understanding of the present utility model. The schematic embodiments and descriptions thereof of the present utility model are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0036] Figure 1 is a schematic structural diagram of the thermal runaway protection device in the embodiment of the present application;

[0037] Figure 2 is a schematic structural diagram of the inflation assembly in the embodiment of the present application;

[0038] Figure 3 is a schematic structural diagram of the exhaust assembly in the embodiment of the present application;

[0039] Figure 4 is a schematic structural diagram of the battery pack in the embodiment of the present application.

[0040] Description of the reference numerals:

[0041] 1. Inflation assembly;

[0042] 101. Storage tank; 1011. Pressure sensor; 102. Inflation tube; 103. Inflation pump; 104. Inflation valve;

[0043] 2. Exhaust assembly;

[0044] 201. Exhaust pipe; 202. Exhaust pump; 203. Exhaust valve; 204. Filter;

[0045] 3. Control assembly;

[0046] 301. Oxygen concentration sensor; 302. Control panel;

[0047] 4. Battery pack;

[0048] 401. Battery management system. Detailed implementation manners

[0049] It should be noted that, without conflict, the embodiments and features in the embodiments of the present utility model can be combined with each other. In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the specific implementation manners of the present utility model will be described below with reference to the drawings. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings, and other implementation manners can also be obtained.

[0050] In the description of the present utility model, it should be noted that if terms indicating orientation or positional relationship such as "upper", "lower", "inner", "outer", etc. appear, they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation to the present utility model. In addition, if terms such as "first" and "second" appear, they are also only for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0051] Taking a thermal runaway protection device and a battery pack described in the present utility model as an example, the orientation terms such as "upper, lower, left, right, front, and back" used in the embodiments are defined based on the up-down direction (also known as the height direction, or the Z direction of the battery pack), the left-right direction (also known as the width direction, or the Y direction of the battery pack), and the front-back direction (also known as the length direction, or the X direction of the battery pack) of the battery pack. "Inner" and "outer" are defined based on the contour of the corresponding component. For example, "inner" and "outer" defined based on the contour of the battery pack, the side closer to the middle of the battery pack is "inner", and vice versa is "outer".

[0052] In addition, in the description of the present utility model, unless otherwise clearly defined, the terms "installation", "connection", "connection", and "connector" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood in combination with specific situations.

[0053] The following will refer to the attached Figure 1 to the attached Figure 4 and will elaborate on the present utility model in conjunction with embodiments.

[0054] Embodiment 1

[0055] This embodiment relates to a thermal runaway protection device, which reduces the oxygen content in the battery pack by filling inert gas into the battery pack, making the environment in the battery pack not meet the conditions for combustion to occur, so as to achieve the invention purpose of avoiding open flames inside the battery pack after the battery pack undergoes thermal runaway, and improving the overall thermal runaway protection performance and electrical safety performance of the battery pack.

[0056] In terms of the overall structure, referring to Figure 1 and Figure 2 , the thermal runaway protection device of this embodiment includes an inflation assembly 1, an exhaust assembly 2, and a control assembly 3. The battery pack adapted by the thermal runaway protection device in this embodiment includes a first explosion-proof valve and a second explosion-proof valve. The inflation assembly 1 is installed on the first explosion-proof valve, and the exhaust assembly 2 is installed on the second explosion-proof valve. The control assembly 3 is installed outside the battery pack and is electrically connected to the inflation assembly 1 and the exhaust assembly 2.

[0057] With the above settings, when the control assembly 3 detects that there is oxygen in the environment inside the battery pack and there is a risk of open flames after the battery pack undergoes thermal runaway, the inflation assembly 1 and the exhaust assembly 2 will start to operate under the control of the control assembly 3. The inflation assembly 1 will fill nitrogen or other flame-retardant inert gas into the battery pack. The exhaust assembly 2 can discharge the original oxygen-containing gas in the battery pack to ensure the balance of the internal and external pressures of the battery pack. When most or all of the oxygen-containing gas in the battery pack is replaced by inert gas, the internal environment no longer meets the conditions for open flame combustion. Even if the battery pack experiences thermal runaway, there will be no open flame combustion or even explosion, thus achieving the invention purpose of avoiding open flames after the battery pack undergoes thermal runaway, and having the advantages of good thermal runaway protection performance and high electrical safety.

[0058] Based on the above design concept, specifically, in this embodiment, referring to Figure 1 and Figure 2, the inflation assembly 1 includes a storage tank 101, an inflation pipe 102, an inflation pump 103 and an inflation valve 104. Among them, the storage tank 101 can be a pressure vessel made of metal with a refill function. The storage tank 101 has a filling port and a discharge port. The filling port is used to refill the inert gas into the storage tank 101 repeatedly, and the discharge port is used to discharge the inert gas in the storage tank 101. One end of the inflation pipe 102 is communicated with the exhaust port of the storage tank 101, and the other end of the inflation pipe 102 is communicated with the first explosion-proof valve on the battery pack. The inflation pump 103 is installed on the inflation pipe 102 and can assist the inert gas in the storage tank 101 to enter the interior of the battery pack through the inflation pipe 102 by means of mechanical pressurization. The inflation valve 104 is installed on the inflation pipe 102 and is used to control the on-off of the air flow in the inflation pipe 102. The inflation valve 104 can be selected as an electromagnetic valve. Both the inflation valve 104 and the inflation pump 103 are electrically connected to the control assembly 3 and can be opened or closed under the control of the control assembly 3.

[0059] By setting the inflation assembly 1 as a combination of the storage tank 101, the inflation pipe 102, the inflation pump 103 and the inflation valve 104, the storage tank 101 therein can be used as a container for storing inert gas; the inflation pipe 102 can be used as a channel for the inert gas to enter the battery pack from the storage tank 101; the inflation pump 103 can provide power for the directional movement of the inert gas; the inflation valve 104 can be used to control the on-off of the air flow in the inflation pipe 102. Cooperating with the inflation pump 103, the inflation assembly 1 can realize the filling of inert gas inside the battery pack under the control of the control assembly 3.

[0060] Refer to Figure 1 and Figure 3 , in order to be able to discharge the gas containing oxygen in the battery pack and maintain the air pressure balance inside and outside the battery pack, the exhaust assembly 2 in this embodiment includes an exhaust pipe 201, an exhaust pump 202 and an exhaust valve 203. Among them, one end of the exhaust pipe 201 is communicated with the second explosion-proof valve of the battery pack. The exhaust pump 202 is installed on the exhaust pipe 201 and can generate negative pressure and discharge the gas in the battery pack along the exhaust pipe 201. The exhaust valve 203 is installed on the exhaust pipe 201 and is used to control the on-off of the air flow in the exhaust pipe 201. The exhaust valve 203 can be selected as a pressure check valve. The exhaust pump 202 is electrically connected to the control assembly 3 and can be opened or closed under the control of the control assembly 3.

[0061] By setting the exhaust assembly 2 as a combination of the exhaust pipe 201, the exhaust pump 202 and the exhaust valve 203. The exhaust pipe 201 therein can be used as a channel for discharging the gas in the battery pack; the exhaust pump 202 can generate negative pressure under the control of the control assembly 3 to assist the gas inside the battery pack to be discharged along the exhaust pipe 201; the exhaust valve 203 can be opened when the pressure reaches a certain value, so that the exhaust pipe 201 has the function of one-way conduction.

[0062] Referring to Figure 1 and Figure 4 In order to be able to control the inflation component 1 and the exhaust component 2, so that the environment inside the battery pack can automatically be maintained in a safe state where open flame combustion cannot be achieved, the control component 3 in this embodiment includes an oxygen concentration sensor 301 and a control panel 302. Among them, the oxygen concentration sensor 301 is arranged inside the battery pack, used to detect the oxygen concentration content inside the battery pack, and convert it into an electrical signal and transmit it to the control panel 302. The control panel 302 can be electrically connected to the inflation component 1 and the exhaust component 2 respectively.

[0063] By setting the control component 3 as a combination of the oxygen concentration sensor 301 and the control panel 302, after the control panel 302 receives the detection signal from the oxygen concentration sensor 301, it controls the inflation component 1 and the exhaust component 2 to start operating until the oxygen concentration inside the battery pack drops to a preset critical value where open flame cannot be generated, and then controls the inflation component 1 and the exhaust component 2 to stop operating.

[0064] Referring to Figure 1 and Figure 3 In order to reduce environmental pollution, in this embodiment, the exhaust component 2 further includes a filter 204, and the filter 204 is arranged at one end of the exhaust pipe 201 away from the battery pack. Activated carbon or other adsorption filters are arranged inside the filter 204, which can adsorb and purify the gas discharged by the exhaust component 2.

[0065] Referring to Figure 1 and Figure 2 In order to further improve the usability of this application, a pressure sensor 1011 is installed on the storage tank 101 in this embodiment. The pressure sensor 1011 is electrically connected to the control panel 302, and can convert the remaining gas pressure information of the storage tank 101 into an electrical signal and transmit it to the control panel 302.

[0066] By setting the pressure sensor 1011 on the storage tank 101, it can be used to detect the gas pressure inside the storage tank 101, so as to prompt the user of the content of the remaining inert gas in the storage tank 101, which is convenient for the user to refill the storage tank 101.

[0067] Embodiment Two

[0068] This embodiment relates to a battery pack. The battery pack in this embodiment includes a first explosion-proof valve and a second explosion-proof valve. Both the first explosion-proof valve and the second explosion-proof valve are installed on the outer shell of the battery pack. The battery pack in this embodiment further includes the thermal runaway protection device involved in Embodiment 1. The installation method and setting method of the thermal runaway protection device in this embodiment are the same as those described in Embodiment 1, and will not be elaborated here for the sake of brevity.

[0069] Both the first explosion-proof valve and the second explosion-proof valve are pressure valves. By setting pressure valves on the outer shell of the battery pack, when the pressure inside the battery pack reaches a certain value, the first explosion-proof valve and the second explosion-proof valve open and connect the inside of the battery pack with the outside world, thereby playing a role in explosion-proof pressure relief.

[0070] In addition, referring to Figure 4 , the battery pack 4 further includes a battery management system 401. The battery management system 401 is used to detect and manage the charge and discharge states of the battery cells in the battery pack 4.

[0071] By setting the battery management system 401 on the battery pack 4, the battery management system 401 can detect and control the switching of the charge and discharge states of the battery pack 4, and can avoid problems such as shortened lifespan or electrical safety issues caused by overcharging or over-discharging of the battery cells.

[0072] For the purpose of further improving the electrical safety of the battery pack, in this embodiment, referring to Figure 4 , the first explosion-proof valve and the second explosion-proof valve of the battery pack 4 are respectively arranged on two parallel sides of the outer shell of the battery pack 4.

[0073] By respectively arranging the first explosion-proof valve and the second explosion-proof valve on two parallel sides of the outer shell of the battery pack 4, the inflation component and the exhaust component can be placed at both ends of the outer shell of the battery pack 4. The above setting can further improve the completeness of the thermal runaway protection device to replace the oxygen-containing gas with inert gas inside the battery pack 4, further reduce the oxygen content in the battery pack 4, and thus achieve the invention purpose of improving electrical safety.

[0074] In order to further improve the convenience of the battery pack in this embodiment, in this embodiment, referring to Figure 4 , the battery management system 401 is electrically connected to the oxygen concentration sensor 301.

[0075] By setting an electrical connection structure between the oxygen concentration sensor 301 and the battery management system 401, the oxygen concentration value inside the battery pack 4 can be directly transmitted to the vehicle computer and displayed through the battery management system 401. It is convenient for users to master the state of the battery pack.

[0076] In order to further improve the convenience of the battery pack in this embodiment, in this embodiment, referring toFigure 4 , the battery management system 401 is electrically connected to the pressure sensor 1011.

[0077] By setting an electrical connection structure between the pressure sensor 1011 and the battery management system 401, the remaining gas pressure value in the storage tank 101 can be directly transmitted to the vehicle computer through the battery management system 401 and displayed. This facilitates the user to grasp the remaining gas quantity in the storage tank 101.

[0078] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A thermal runaway protection device for thermal runaway protection of a battery pack, the battery pack comprising a first explosion-proof valve and a second explosion-proof valve, characterized in that: A gas filling assembly is provided on the first explosion-proof valve and communicated with the battery pack, and is used to fill the battery pack with an inert gas; an exhaust assembly, disposed on the second explosion-proof valve and connected to the battery pack; A control component is electrically connected to the inflation component and the exhaust component, and is used to control the start and stop of the inflation component and the exhaust component.

2. The thermal runaway protection device according to claim 1, characterized in that: The inflation assembly includes a storage tank filled with compressed inert gas; An air filling pipe, one end of which is connected to the storage tank, and the other end of which is connected to the first explosion-proof valve; an air pump, disposed on the air filling tube, and used to fill the gas in the air filling tube into the battery pack; The inflation valve is arranged on the inflation pipe and is used to control the on-off of the airflow in the inflation pipe.

3. The thermal runaway protection device according to claim 2, characterized in that: The exhaust assembly includes an exhaust pipe, one end of which is connected to the second explosion-proof valve; an exhaust pump, disposed on the exhaust pipe, for exhausting the gas in the battery pack through the exhaust pipe; The exhaust valve is arranged on the exhaust pipe and is used to control the on-off of the airflow in the exhaust pipe.

4. The thermal runaway protection device according to claim 3, characterized in that: The control component includes an oxygen concentration sensor, which is disposed in the battery pack and is used to detect the oxygen concentration in the battery pack; A control panel is electrically connected to the oxygen concentration sensor, the inflation component and the exhaust component, and is used to control the start and stop of the inflation component and the exhaust component.

5. The thermal runaway protection device according to claim 3, characterized in that: The exhaust assembly further includes a filter, which is disposed on an end of the exhaust pipe away from the battery pack.

6. The thermal runaway protection device according to claim 4, characterized in that: The storage tank is provided with a pressure sensor, and the pressure sensor is electrically connected to the control panel.

7. A battery pack, comprising a first explosion-proof valve and a second explosion-proof valve, characterized in that: It also includes a thermal runaway protection device, which adopts the thermal runaway protection device as described in any one of claims 1 to 6; A battery management system is used for controlling the charge and discharge of the battery pack.

8. The battery pack according to claim 7, characterized in that: The first explosion-proof valve and the second explosion-proof valve are disposed on two parallel sides of the battery pack.

9. The battery pack according to claim 7, characterized in that: The battery management system is electrically connected to the oxygen concentration sensor.

10. The battery pack according to claim 7, characterized in that: The battery management system is electrically connected to the pressure sensor.

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