Device and method for testing maximum overpressure of in-situ explosion of battery thermal runaway spray

Abstract

The invention discloses a device and a method for testing the maximum overpressure of in-situ explosion of a battery thermal runaway jet in the technical field of battery experimental testing, and aims to solve the problem that the test accuracy is influenced due to the fact that the explosion characteristic generated by thermal runaway gas cannot be really reduced in the prior art. The device comprises an explosion cabin, the explosion cabin is detachably connected with a cabin door used for sealing the explosion cabin, and the cabin door is provided with an explosion venting window; a weighing mechanism is detachably connected to the interior of the explosion cabin, and a clamp for clamping a battery is detachably connected to the weighing mechanism; according to the invention, the mass change of the battery can be obtained in real time through the weighing mechanism, and the quantity of the thermal runaway eject can be known in real time according to the mass change of the battery, so that the thermal runaway eject with a certain quantity is exploded, and the most real overpressure characteristic of the explosion of the thermal runaway eject can be monitored; meanwhile, the device and the method provided by the invention are extremely low in implementation cost and easy to operate.

Description

TECHNICAL FIELD

[0001] The application relates to a battery thermal runaway jet in-situ explosion maximum overpressure testing device and method, and belongs to the technical field of battery experiment testing. BACKGROUND

[0002] With the continuous development and application of electric vehicles and new energy power generation, batteries gradually become the main choice of energy storage media due to their high energy density and long service life. However, frequent energy storage safety accidents and electric vehicle fires have attracted much attention to the safety of batteries. The battery itself is composed of active materials and organic electrolyte. The organic electrolyte has high flammability. When the battery is in an abuse condition, the battery will enter a thermal runaway state. At this time, the pressure relief valve of the battery will open and a large amount of mixture will be sprayed. If no measures are taken in time, the battery will enter a thermal runaway state and a large amount of white smoke will be sprayed from the valve opening. The substances sprayed from the battery after the valve is opened are highly flammable. When these substances are in a closed environment, they are likely to cause an explosion. It is of great significance to prevent accidents and reduce casualties to study the explosion phenomenon that may occur after the battery enters a thermal runaway state, understand the conditions under which the explosion occurs, and the power of the explosion.

[0003] At present, the test method for the explosion characteristics of battery thermal runaway jet is usually a gas mixing point explosion and in-situ point explosion. The common gas mixing point explosion test method usually places the battery in a closed environment, then triggers the thermal runaway of the battery, detects the gas composition and content generated by the thermal runaway of the battery, reconfigures the gas according to the detected gas composition, and finally performs a point explosion on the reconfigured mixed gas in the explosion sphere to test the explosion power and other related characteristic data. Although this method can accurately control the content and specific composition of the thermal runaway gas at the time of point explosion, it ignores the influence of a large amount of electrolyte vapor generated by the battery thermal runaway on the explosion characteristics. Because these organic vapors are also flammable and explosive substances, there are unavoidable errors in the detection and configuration of the gas composition, so this test method cannot truly restore the explosion characteristics of the thermal runaway gas. The in-situ point explosion test device can only test the explosion of small capacity batteries, cannot control the content of the thermal runaway gas at the time of point explosion, and requires high professional and safety requirements of related equipment, usually with expensive customization fees. Moreover, the current explosion test cannot predict and test the maximum overpressure of the thermal runaway products of the battery.

[0004] As can be seen from the above, the existing battery explosion test method usually ignores the influence of a large amount of electrolyte vapor generated by the battery thermal runaway on the explosion characteristics, and cannot truly restore the explosion characteristics of the thermal runaway gas, affecting the accuracy of the test. SUMMARY

[0005] The purpose of the present application is to overcome the deficiencies in the prior art, provide a battery thermal runaway ejecta in-situ explosion maximum overpressure testing device and method, which can obtain the change of battery mass in real time through the weighing mechanism, and understand the amount of thermal runaway ejecta in real time according to the change of battery mass, so as to point the explosion of a certain amount of thermal runaway ejecta, so that the most real overpressure characteristics of thermal runaway ejecta explosion can be monitored, and the device and method provided by the present application have extremely low cost and are easy to operate.

[0006] To solve the above technical problems, the present application is realized by adopting the following technical solutions:

[0007] In a first aspect, the present application provides a battery thermal runaway ejecta in-situ explosion maximum overpressure testing device, comprising an explosion cabin, a hatch for sealing the explosion cabin is detachably connected to the explosion cabin, and a venting window is arranged on the hatch;

[0008] A weighing mechanism is detachably connected in the explosion cabin, a clamp for clamping a battery is detachably connected to the weighing mechanism, a first mounting hole for mounting an igniter, a first threading hole for passing through a power line, a second threading hole for passing through a thermocouple, a second mounting hole for mounting a pressure sensor, and a third mounting hole for mounting a fire extinguishing pipeline are arranged on the explosion cabin.

[0009] Further, a plurality of screw mounting holes for mounting fixing screws are arranged on the hatch, and the hatch is detachably connected with the explosion cabin through the fixing screws.

[0010] Further, a sealing gasket is arranged between the explosion cabin and the hatch, and screw holes for passing through the fixing screws are arranged on the sealing gasket.

[0011] Further, a support is arranged at the bottom of the explosion cabin.

[0012] Further, the fire extinguishing pipeline is located on the valve port side of the battery.

[0013] Further, the weighing mechanism is placed at the center position of the inner wall bottom of the explosion cabin, and the clamp is placed at the top center position of the weighing mechanism.

[0014] In a second aspect, the present application provides a battery thermal runaway ejecta in-situ explosion maximum overpressure testing method based on the battery thermal runaway ejecta in-situ explosion maximum overpressure testing device of the first aspect, comprising the following steps:

[0015] Step a: obtaining the volume of the explosion cabin and the temperature in the cabin;

[0016] Step b: calculating the lower explosion limit and the upper explosion limit according to the volume of the explosion cabin and the temperature in the cabin.

[0017] Step c: Place the battery into the clamp and connect the battery to the power line, then seal the explosive compartment through the hatch;

[0018] Step d: Control the battery to induce overcharge thermal runaway through the power line, and record the amount of thermal runaway ejected from the battery in real time through a weighing mechanism;

[0019] Step e: Calculate the first detection value, the second detection value, and the third detection value based on the lower explosive limit and the upper explosive limit;

[0020] Step f: When the amount of thermal runaway ejected from the battery reaches the lower explosive limit, ignite the explosion and obtain the lower explosive overpressure.

[0021] Step g: Repeat steps c, d, e and f, replacing the lower explosion limit in step f with the upper explosion limit, the first detection value, the second detection value and the third detection value respectively, to obtain the upper explosion overpressure, the first explosion overpressure, the second explosion overpressure and the explosion overpressure;

[0022] Step h: Based on the lower explosion limit, upper explosion limit, first detection value, second detection value, third detection value, lower explosion overpressure, upper explosion overpressure, first explosion overpressure, second explosion overpressure, and explosion overpressure, the least squares method is used to fit the log-normal distribution function to obtain the output function;

[0023] Step i: Obtain the peak explosion value of the function based on the output function. Repeat steps c, d, e and f, replacing the lower explosion limit in step f with the peak explosion value of the function to obtain the maximum explosion overpressure.

[0024] Furthermore, the specific expressions for calculating the lower explosion limit and the upper explosion limit are as follows:

[0025] ;

[0026] ;

[0027] In the formula: This is the lower limit of the explosive quantity. This is the maximum explosive limit. This is the lower limit of explosiveness; This is the maximum explosive limit; The cabin pressure; The volume of the explosion chamber; The serial number of the ejected material; For the first The volume percentage of the ejected material; For the first Molar mass of the ejected material; For the first The lower explosive limit of the ejected material; is the explosion upper limit of the first detection value; is the gas constant; is the cabin temperature of the explosion cabin. Further, the first detection value, the second detection value and the third detection value are calculated, and the specific expression is as follows:

[0028]

[0029]

[0030]

[0031]

[0032] In the formula: is the first detection value; is the second detection value; is the third detection value.

[0033] Further, the least square method is used to fit the lognormal distribution function, and the specific expression is as follows:

[0034]

[0035] In the formula: is the amount of battery thermal runaway spray, including the explosion lower limit, the explosion upper limit, the first detection value, the second detection value and the third detection value; is the estimated overpressure, including the lower explosion overpressure, the upper explosion overpressure, the first explosion overpressure, the second explosion overpressure and the explosion overpressure; is the function parameter; represents an exponential function , is a real number;

[0036] The function peak explosion amount is obtained according to the output function, and the specific expression is as follows:

[0037]

[0038] In the formula: is the function peak explosion amount.

[0039] Compared with the prior art, the beneficial effects achieved by the present application are:

[0040] ​​​​​​​​1. The battery thermal runaway ejecta in-situ explosion maximum overpressure testing device can obtain the change of battery mass in real time through the weighing mechanism, understand the amount of thermal runaway ejecta in real time according to the change of battery mass, and carry out point explosion on the determined amount of thermal runaway ejecta; the amount of thermal runaway ejecta at the point explosion moment is controlled, so that the most real overpressure characteristics of thermal runaway ejecta explosion are monitored, the device and the method provided by the application have extremely low implementation cost, and the operation is easy;

[0041] 2. The battery thermal runaway ejecta in-situ explosion maximum overpressure testing device, the clamp can be replaced according to needs, and the explosion cabin and the explosion venting window on the cabin door can also be replaced according to needs, so that more battery explosion testing scenes can be applied;

[0042] 3. The battery thermal runaway ejecta in-situ explosion maximum overpressure testing method can obtain experimental data such as the volume of the explosion cabin and the temperature in the cabin, can obtain the maximum explosion overpressure data of the battery ejecta combustion explosion according to the experimental data and through fitting estimation, can more clearly understand the necessary conditions and accident power of battery combustion explosion accidents, provides necessary data reference for safety design, accident prevention and accident treatment, and improves the safety in the battery application scene. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 It is a three-dimensional structure schematic diagram of a battery thermal runaway ejecta in-situ explosion maximum overpressure testing device provided by the embodiment of the application;

[0044] Figure 2 It is a three-dimensional structure schematic diagram of an explosion cabin provided by the embodiment of the application;

[0045] Figure 3 It is a three-dimensional structure schematic diagram of the explosion cabin when the cabin door is installed;

[0046] Figure 4 It is a three-dimensional structure schematic diagram of a support provided by the embodiment of the application;

[0047] Figure 5 It is a front view structure schematic diagram of a cabin door provided by the embodiment of the application;

[0048] Figure 6 It is a flowchart of a battery thermal runaway ejecta in-situ explosion maximum overpressure testing method provided by the embodiment of the application;

[0049] Figure 7 It is a curve schematic diagram of an output function provided by the embodiment of the application.

[0050] In the diagram: 21. Explosion chamber; 22. Door; 23. Screw mounting hole; 24. Sealing gasket; 25. Support component; 31. Explosion relief window; 41. First mounting hole; 42. First wiring hole; 43. Second wiring hole; 44. Second mounting hole; 45. Third mounting hole; 46. Clamp; 47. Weighing mechanism. Detailed Implementation

[0051] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations thereof. In the absence of conflict, the embodiments of the present invention and the technical features in the embodiments can be combined with each other.

[0052] The term "and / or" simply describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. Additionally, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0053] Example 1:

[0054] like Figures 1-5 As shown, the present invention provides a maximum overpressure test device for in-situ explosion of battery thermal runaway ejecta, including an explosion chamber 21, wherein a door 22 for sealing the explosion chamber 21 is detachably connected to the explosion chamber 21, and the door 22 is provided with an explosion relief window 31;

[0055] The explosion chamber 21 is detachably connected to a weighing mechanism 47, and the weighing mechanism 47 is detachably connected to a clamp 46 for holding the battery. The explosion chamber 21 is provided with a first mounting hole 41 for installing an igniter, a first wire hole 42 for passing through a power line, a second wire hole 43 for passing through a thermocouple, a second mounting hole 44 for installing a pressure sensor, and a third mounting hole 45 for installing a fire extinguishing pipe.

[0056] Specifically, the explosion cabin 21 is used to install various sensors on its surface or penetrate into the inside and conduct battery thermal runaway explosion experiments; the cabin door 22 is used to connect with the explosion cabin 21 to form a sealed whole; the explosion vent 31 is used to release pressure when the pressure in the explosion cabin 21 is too high; the first mounting hole 41 is used to install different types of igniters to achieve the ignition of the thermal runaway spray in the explosion cabin 21, the igniter is a device for igniting the thermal runaway spray to cause explosion, the principle of the igniter includes but is not limited to high-temperature arc ignition and electric spark ignition; the first threading hole 42 is a power line threading hole and other wire threading hole, which is used to thread the power line into the inside of the explosion cabin 21 to achieve the overcharge thermal runaway of the battery and the threading of other necessary wires, including but not limited to the wires of the heating device, the power line is used for charging and discharging the battery and overcharge thermal runaway, which is usually controlled by the battery test system; the second threading hole 43 is used to thread the thermocouple into the inside of the explosion cabin 21 to achieve the monitoring of the over-temperature during the explosion in the explosion cabin 21, the thermocouple is used to monitor the over-temperature at the moment of explosion, the temperature measuring principle of the thermocouple includes but is not limited to K-type thermocouple and tungsten-rhenium thermocouple; the second mounting hole 44 is used to install a pressure sensor to achieve the collection of explosion overpressure data in the explosion cabin 21, the pressure sensor is a sensor for detecting the overpressure generated at the moment of explosion, the principle of the pressure sensor includes but is not limited to piezoelectric pressure sensor and piezoresistive pressure sensor; the third mounting hole 45 is used to install a fire extinguishing pipeline to avoid the long-time burning in the explosion cabin 21 after explosion, the fire extinguishing pipeline is used to extinguish the flame that may exist in the device after the explosion of the thermal runaway spray; the clamp 46 is used to fix the experimental battery, apply pre-tightening force to the battery and trigger the thermal runaway of the battery; the weighing mechanism 47 is a precision weighing platform, which is used to weigh the mass change of the battery to achieve real-time monitoring of the mass of the thermal runaway spray of the battery.

[0057] Optionally, the battery includes cylindrical batteries, square batteries and soft package batteries; the explosion cabin 21 is a semi-closed cabin, which is composed of five surfaces of the same size, and the test device can be arranged in the inside of the explosion cabin 21; the second mounting hole 44 is a reserved hole for installing an explosion pressure sensor, which is located at the center of each surface of the explosion cabin 21 except the bottom surface; the explosion vent 31 is a device for passive pressure relief after explosion in the explosion cabin 21, which avoids the damage of the device caused by the excessive pressure in the device, which can be opened to release pressure when the pressure exceeds a certain threshold, thereby rapidly reducing the pressure in the device; optionally, the explosion vent 31 can be fixed on the surface of the cabin door 22 by welding or bolts, and finally the appropriate explosion threshold can be determined according to the experimental results and the use scene, which reduces the difficulty of designing the explosion threshold of the explosion vent 31 and improves the safety of battery energy storage.

[0058] As Figure 5As shown in the embodiment, a plurality of screw mounting holes 23 for mounting fixing screws are formed on the hatch door 22, and the hatch door 22 is detachably connected with the explosion cabin 21 through the fixing screws; the screw mounting holes 23 are used for mounting the fixing screws to connect and fix the explosion cabin 21 and the hatch door 22; a sealing gasket 24 is arranged between the explosion cabin 21 and the hatch door 22, and a screw hole for passing through the fixing screw is formed on the sealing gasket 24; the sealing gasket 24 is used to ensure the sealing between the hatch door 22 and the explosion cabin 21, and ensure the sealing in the experiment process of the application; optionally, the sealing gasket 24 is integrally formed.

[0059] As shown in the embodiment, Figure 4 As shown in the embodiment, a support 25 is arranged at the bottom of the explosion cabin 21 to ensure that the explosion cabin 21 is in a stable state; the fire extinguishing pipeline is arranged at the valve port side of the battery, and specifically, the outlet position of the fire extinguishing pipeline is opposite to the valve port of the battery from the position of the side surface of the battery, so as to ensure the fire extinguishing effect on the battery; optionally, the fire extinguishing medium used by the fire extinguishing pipeline includes but is not limited to dry powder, carbon dioxide and fine water mist.

[0060] In an embodiment, the weighing mechanism 47 is placed at the center position of the inner wall bottom of the explosion cabin 21, and the clamp 46 is placed at the top center position of the weighing mechanism 47.

[0061] The application can obtain the change of the battery mass in real time through the weighing mechanism 47, and can know the amount of thermal runaway spray in real time according to the change of the battery mass, so as to point and explode the determined amount of thermal runaway spray; the clamp 46 can be replaced according to the needs, and the explosion cabin 21 and the hatch door 22 can also be replaced according to the needs, so as to be applicable to more battery explosion test scenes; the in-situ thermal runaway triggering of various batteries can be realized, and the amount of thermal runaway spray at the point explosion moment can be controlled, so that the most real overpressure characteristics of the thermal runaway spray explosion can be monitored, and the cost required for the implementation of the device and method provided by the application is extremely low, and the operation is easy.

[0062] The application provides a test device which can realize low-cost, in-situ and repeatable thermal runaway spray point explosion of various batteries, the device can trigger the thermal runaway of the battery at a low cost, realize the in-situ point explosion of the thermal runaway spray, and control the amount of the thermal runaway spray at the point explosion moment, so as to effectively improve the accuracy, rigor and repeatability of the explosion overpressure characteristic test.

[0063] Embodiment two:

[0064] As shown in the embodiment, Figure 6As shown, the present application provides a battery thermal runaway jet in-situ explosion maximum overpressure test method, based on the battery thermal runaway jet in-situ explosion maximum overpressure test device described in embodiment one, comprising the following steps:

[0065] Step a: obtain the volume of the explosion cabin 21 and the temperature inside the cabin;

[0066] Step b: calculate the lower explosion limit and the upper explosion limit according to the volume of the explosion cabin 21 and the temperature inside the cabin;

[0067] Step c: place the battery in the clamp 46, connect the battery with the power line, and seal the explosion cabin 21 through the cabin door 22;

[0068] Step d: control the battery to overheat and lose control through the power line, and record the amount of battery thermal runaway jet in real time through the weighing mechanism 47;

[0069] Step e: calculate the first detection value, the second detection value and the third detection value according to the lower explosion limit and the upper explosion limit;

[0070] Step f: when the amount of battery thermal runaway jet reaches the lower explosion limit, perform a point explosion and obtain the lower explosion overpressure;

[0071] Step g: repeat steps c, d, e and f, respectively replace the lower explosion limit in step f with the upper explosion limit, the first detection value, the second detection value and the third detection value to obtain the upper explosion overpressure, the first explosion overpressure, the second explosion overpressure and the explosion overpressure;

[0072] Step h: according to the lower explosion limit, the upper explosion limit, the first detection value, the second detection value, the third detection value, the lower explosion overpressure, the upper explosion overpressure, the first explosion overpressure, the second explosion overpressure and the explosion overpressure, use the least squares method to fit the lognormal distribution function to obtain the output function;

[0073] Step i: according to the output function, obtain the function peak explosion amount, repeat steps c, d, e and f, replace the lower explosion limit in step f with the function peak explosion amount to obtain the maximum explosion overpressure.

[0074] In one embodiment, the lower explosion limit and the upper explosion limit are calculated as follows:

[0075] ;

[0076] ;

[0077] In the formula: is the lower explosion limit, is the upper explosion limit, is the lower explosion limit; is an upper explosive limit amount; is an internal pressure of the cabin; is a volume of the explosion cabin 21; is a serial number of the ejecta; is a volume ratio of the first ejecta; is a volume ratio of the first ejecta; is a molar mass of the first ejecta; is a molar mass of the first ejecta; is a lower explosive limit of the first ejecta; is a lower explosive limit of the first ejecta; is an upper explosive limit of the first ejecta; is an upper explosive limit of the first ejecta; is a gas constant; is an internal temperature of the explosion cabin 21.

[0078] In one embodiment, the first detection value, the second detection value, and the third detection value are calculated, and the specific expression is as follows:

[0079] ;

[0080] ;

[0081] ;

[0082] In the formula: is the first detection value; is the second detection value; is the third detection value.

[0083] As shown in Figure 7 , in one embodiment, the least square method is used for fitting the lognormal distribution function, and the specific expression is as follows:

[0084] ;

[0085] In the formula: is the amount of battery thermal runaway ejecta, including the lower explosive limit amount, the upper explosive limit amount, the first detection value, the second detection value, and the third detection value; is the estimated overpressure, including the lower explosive overpressure, the upper explosive overpressure, the first explosive overpressure, the second explosive overpressure, and the explosive overpressure; , , is a function parameter; represents an exponential function , is a real number;

[0086] The function peak explosion amount is obtained according to the output function, and the specific expression is as follows:

[0087] ;

[0088] In the formula: is the function peak explosion amount.

[0089] The maximum explosion overpressure of the explosion refers to the maximum overpressure generated by the explosion under the condition of a certain amount of injection, and the overpressure generated by the explosion under the condition of any other amount of injection is less than the value; the test method refers to a method of estimating the explosion limit and overpressure curve of the thermal runaway injection and finally obtaining the maximum explosion overpressure by combining the test; a series of side reactions occur in the early stage and during the thermal runaway of the battery, and the battery sprays flammable and explosive mixtures such as hydrogen, carbon monoxide, and methane from the safety valve port, and the composition is extremely complex, so the test device for the explosion overpressure characteristics of the battery thermal runaway injection needs to be able to ensure the in-situ thermal runaway injection detonation, and needs to be able to control the amount of thermal runaway injection to ensure the repeatability of the test.

[0090] In one embodiment, a 100A current is used to overcharge a 280Ah lithium iron phosphate battery in the test, the battery mass is recorded before the valve is opened, and then when the battery is completely thermal runaway and the amount of battery injection is =346g, =823g, =584.5g, =465.25g, =703.75g, the igniter is started, and the overpressure data are respectively lower limit explosion overpressure =155.47kPa, upper limit explosion overpressure =139.25kPa, first explosion overpressure =295.01kPa, second explosion overpressure =307.25kPa, and third explosion overpressure =234.91kPa. It is estimated by fitting that the explosion overpressure is maximum when =490g; the explosion is detonated at =490g, and at the moment of detonation, the pressure in the cabin rises rapidly to a maximum of 312.15kPa, and then the explosion vent 31 opens and the pressure rapidly decreases; the device is successfully used to realize the in-situ explosion maximum overpressure test of the battery thermal runaway injection.

[0091] The existing test method can only obtain explosion overpressure data, but cannot obtain the maximum overpressure of the battery thermal runaway injection, while the present application can obtain experimental data such as the volume of the explosion cabin 21 and the temperature in the cabin, can obtain the maximum explosion overpressure data of the battery injection explosion according to the experimental data and through fitting estimation, and can more clearly understand the necessary conditions and accident power of battery explosion accidents, thereby providing necessary data reference for safety design, accident prevention, and accident handling, and improving the safety of battery application scenarios.

[0092] Those skilled in the art will appreciate that embodiments of the application can be readily used as software, hardware, or a combination of software and hardware. In a software embodiment, various software modules in accordance with embodiments of the application are stored in a memory such as a computer program product and executed by a processor. As used herein, a computer program product is at least one computer-readable storage medium, and can be a computer- readable storage medium, or machine-readable storage medium, or computer program product, or machine-readable program product. A computer-readable storage medium is any available medium that can be accessed by a computer. By way of example, and not limitation, computer-readable storage media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired computer program code in the form of computer- readable instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, or twisted pair, then the coaxial cable, fiber optic cable, or twisted pair are included in the definition of medium. Disk and disc, as used herein, include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), and Blu-Ray® disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0093] In this document, the terms "computer program medium" and "computer-usable medium" are used to generally refer to media such as removable storage media, memory storage media, and / or storage media that is used in the operation of a computer system. Such computer program media include, but are not limited to, a magnetic storage device, an optical storage device, a memory device, a solid state device, and the like. Such computer program media are also used to store and / or transport software program code, data, or both. Figure One Figure One

[0094] Figure One Figure One

[0095] Figure One Figure One

[0096] The foregoing is considered as illustrative only of the principles of the application. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the application to the exact construction and practice described. Accordingly, all such variations are intended to be included within the scope of the present application as defined in the claims below.​​​​​​​​

Claims

1. A battery thermal runaway ejecta in-situ explosion maximum overpressure test device, characterized in that, The explosion cabin is detachably connected with a cabin door for sealing the explosion cabin, and the cabin door is provided with a blast vent; A weighing mechanism is detachably connected in the explosion cabin, and a clamp for clamping the battery is detachably connected on the weighing mechanism.

2. The battery thermal runaway ejecta in situ explosion overpressure test apparatus of claim 1, wherein, A plurality of screw mounting holes for mounting fixing screws are formed on the cabin door, and the cabin door is detachably connected with the explosion cabin through the fixing screws.

3. The battery thermal runaway ejecta in situ explosion overpressure test apparatus of claim 2, wherein, A sealing gasket is arranged between the explosion cabin and the cabin door, and screw holes for passing through the fixing screws are formed on the sealing gasket.

4. The battery thermal runaway ejecta in situ explosion overpressure test apparatus of claim 1, wherein, The bottom of the explosion cabin is provided with a support.

5. The battery thermal runaway ejecta in situ explosion overpressure test apparatus of claim 1, wherein, The fire extinguishing pipeline is located on the side of the valve port of the battery.

6. The battery thermal runaway ejecta in situ explosion overpressure test apparatus of claim 1, wherein, The weighing mechanism is placed at the center position of the inner wall bottom of the explosion cabin, and the clamp is placed at the top center position of the weighing mechanism.

7. A method for testing the maximum overpressure of battery thermal runaway jet in-situ explosion based on the battery thermal runaway jet in-situ explosion maximum overpressure testing device according to any one of claims 1-6, characterized in that, The method comprises the following steps: Step a: obtaining the volume and the temperature in the cabin of the explosion cabin; Step b: calculating the lower explosion limit and the upper explosion limit according to the volume and the temperature in the cabin of the explosion cabin; Step c: placing the battery in the clamp and connecting the battery with the power line, and sealing the explosion cabin through the cabin door; Step d: controlling the battery to overcharge and heat runaway through the power line, and recording the amount of battery heat runaway spatter in real time through the weighing mechanism; Step e: calculating the first detection value, the second detection value and the third detection value according to the lower explosion limit and the upper explosion limit; Step f: when the amount of battery heat runaway spatter reaches the lower explosion limit, performing point explosion and obtaining the lower limit explosion overpressure; Step g: repeating steps c, d, e and f, respectively replacing the lower explosion limit in step f with the upper explosion limit, the first detection value, the second detection value and the third detection value to obtain the upper limit explosion overpressure, the first explosion overpressure, the second explosion overpressure and the explosion overpressure; Step h: fitting the lognormal distribution function by the least square method according to the lower explosion limit, the upper explosion limit, the first detection value, the second detection value, the third detection value, the lower limit explosion overpressure, the upper limit explosion overpressure, the first explosion overpressure, the second explosion overpressure and the explosion overpressure to obtain an output function; Step i: obtaining the function peak explosion amount according to the output function, repeating steps c, d, e and f, and replacing the lower explosion limit in step f with the function peak explosion amount to obtain the maximum explosion overpressure.

8. The method of battery thermal runaway ejecta in situ explosion overpressure testing of claim 7, wherein, The specific expression of the calculation of the lower explosion limit and the upper explosion limit is as follows: ； ； In the formula: is the lower explosive limit, is the upper explosive limit, is the lower explosive limit; is the upper explosive limit; is the pressure in the chamber; is the volume of the explosion chamber; is the serial number of the ejecta; is the volume fraction of the ejecta; is the molar mass of the ejecta; is the lower explosive limit of the ejecta; is the upper explosive limit of the ejecta; is the gas constant; is the temperature in the chamber of the explosion chamber.

9. The method of battery thermal runaway ejecta in situ explosion overpressure testing of claim 8, wherein, The specific expression of the calculation of the first detection value, the second detection value and the third detection value is as follows: ； ； ； In the formulae: is a first detection value; is a second detection value; is a third detection value.

10. The method of battery thermal runaway ejecta in situ explosion overpressure testing of claim 7, wherein, The specific expression of the fitting of the lognormal distribution function by the least square method is as follows: ； wherein: is the amount of battery thermal runaway ejecta, including lower explosive limit, upper explosive limit, first detection value, second detection value, and third detection value; is the estimated overpressure, including lower explosive overpressure, upper explosive overpressure, first explosive overpressure, second explosive overpressure, and explosive overpressure; , , is a function parameter; denotes an exponential function , is a real number; The specific expression of the calculation of the function peak explosion amount according to the output function is as follows: ； In the formula: is the function peak burst quantity.

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