Experimental equipment for thermal runaway reaction of lithium battery

Abstract

The utility model belongs to the field of experimental equipment, and particularly relates to experimental equipment for thermal runaway reaction of a lithium battery. The equipment is used for carrying out a battery thermal runaway experiment and collecting experimental data after thermal runaway of a lithium battery occurs under the conditions of heating, overcharging, short circuit or needling. The experimental equipment comprises a box body, a battery fixing device, a battery puncturing mechanism, an electrical detection and control device, a heating plate, a video recording device, a temperature sensor, a gas detection suite, a smoke sampling device and an upper computer. Wherein the box body adopts a sealed cabinet type box body, and a box door capable of being opened and closed is arranged in front of the box body. A drain valve is arranged at the bottom of the box body; the top of the back side plate of the box body is provided with an electrical outlet; an air outlet valve is arranged on the back of the box body. Various electric control devices are located in the box body, and an upper computer serves as a control center to achieve remote control and data collection. The scheme has the advantages of being simple in structure, low in cost, rich in function, high in safety, high in automation degree and convenient to use.

Description

Technical Field

[0001] The utility model belongs to the field of experimental equipment, and particularly relates to an experimental equipment for lithium battery thermal runaway reaction. Background Art

[0002] Lithium batteries are commonly used energy storage devices in electronic or electrical equipment. Although lithium batteries are widely used, studying their thermal runaway under extreme conditions is of great significance for improving battery safety. Conventional battery thermal runaway experiments refer to making the battery undergo thermal runaway through external conditions such as pressurization, circuit, puncture, and overheating, and detecting various characteristic parameters of the battery during thermal runaway through sensors. When the battery undergoes thermal runaway, there is a risk of deflagration or even explosion. Therefore, thermal runaway experiments need to be carried out in a safe and controllable environment.

[0003] Currently, professional battery safety research institutions are equipped with professional battery thermal runaway laboratories. The laboratories use transparent heat-resistant glass isolation walls and are equipped with an air circulation system. The laboratories are equipped with a complete set of mechanisms and instruments for performing battery thermal runaway experiments. Technicians can remotely operate the internal mechanisms outside the laboratory to perform battery thermal runaway experiments and collect relevant characteristic parameters of the experimental process through various instruments. For some enterprises and institutions, the cost of designing and installing such professional battery thermal laboratories is too high, and users are more inclined to use some small devices to assist in completing thermal runaway experiments. Currently, there are also some small lithium battery test benches on the market. Technicians can use these test benches to fix lithium batteries and reduce the risk during the thermal runaway experiment process. However, such small devices generally have simple functions, cannot facilitate the implementation of various relatively complex lithium battery thermal runaway experimental projects, and it is difficult to collect experimental data. Summary of the Utility Model

[0004] In order to solve the problem in the prior art that there is a lack of equipment or devices capable of carrying out various lithium battery thermal runaway experiments at low cost, the utility model provides an experimental equipment for lithium battery thermal runaway reaction.

[0005] The technical solution provided by the utility model is as follows:

[0006] An experimental equipment for lithium battery thermal runaway reaction, which is used to carry out battery thermal runaway experiments and collect experimental data of lithium batteries after thermal runaway under conditions of heating, overcharging, short circuit or puncture. The experimental equipment includes: a box body, a battery fixing device, a battery puncture mechanism, an electrical monitoring and control device, a heating plate, a video recording device, a temperature sensor, a gas detection kit, a flue gas sampling device, and a host computer.

[0007] Among them, the box body adopts a sealed cabinet - type box body and is provided with an openable and closable box door in the front. A drain valve is provided at the bottom of the box body; an electrical outlet is provided at the top of the back side plate of the box body; an air outlet valve is also provided on the back of the box body; the air outlet valve adopts an electric control valve.

[0008] The battery fixing device is installed at the center of the inner bottom surface of the box body; the battery fixing device is used to fix the battery pack to be tested. The heating plate is located on the battery fixing device and is used to heat the battery pack.

[0009] The battery puncture mechanism is located inside the box body and above the battery fixing device. The battery puncture mechanism includes a retractable actuator and a puncture needle, and the puncture needle is fixedly connected to the front end of the actuator. The actuator is used to drive the puncture needle to pierce the battery pack downward.

[0010] The electrical monitoring and control device is located outside the box body and is electrically connected to the electrodes of the battery pack located inside the box body through cables. The electrical monitoring and control device is used to perform over - charge or short - circuit operations on the battery pack and detect the electrical parameters during the thermal runaway experiment process of the battery pack.

[0011] The video recording device is installed at the top of the inner wall of the box body, and the viewing area of the video recording device is directly opposite to the lithium battery to be tested below. The video recording device is used to collect the image data at the location of the lithium battery during the thermal runaway experiment process.

[0012] The temperature sensor is installed inside the box body and is used to measure the temperature of the battery pack body and its surrounding environment. The gas detection kit is installed inside the box body and is used to measure the real - time concentrations of CO, H2, VOCs and electrolyte characteristic gases in the box body during the experiment.

[0013] The flue gas sampling device is located outside the box body and is connected to the air outlet valve; the flue gas sampling device is used to collect the characteristic gases generated inside the box body during the experiment.

[0014] The upper computer is located outside the box body; and is electrically connected to the actuator, the electrical monitoring and control device, the heating plate, the camera, the gas detection kit, the air outlet valve, and the temperature sensor. The upper computer is used to issue control instructions for controlling their operating states to the actuator, the electrical monitoring and control device, the heating plate, the video recording device and the air outlet valve during the thermal runaway experiment process. The upper computer is also used to obtain the images or data collected by the electrical monitoring and control device, the video recording device, the gas detection kit and the temperature sensor during the thermal runaway experiment process.

[0015] As a further improvement of the present utility model, the outer shell of the box body includes an inner wall and an outer wall, and a polyurethane foam layer is filled in the interlayer between the inner and outer walls.

[0016] And / or

[0017] The video recording device includes a camera and a fill light; an installation bracket is provided at the top of the inner wall of the box body, and the video recording device is fixedly connected to the installation bracket.

[0018] As a further improvement of the present utility model, the inner wall of the box body further includes a concealed cable channel, which extends from the electrical outlet at the upper part of the box body to the bottom surface of the box body; the cable of the temperature sensor passes through the cable channel.

[0019] As a further improvement of the present utility model, a silica gel sealing ring is provided at the edge of the box door; the box door is provided with a pressure handle, and a locking mechanism corresponding to the position of the pressure handle is provided at the corresponding position in the box body.

[0020] As a further improvement of the present utility model, the gas detection kit includes a CO concentration sensor, an electrolyte integrated gas sensor, a VOCs gas detector and a hydrogen detector.

[0021] The CO concentration sensor, the electrolyte integrated gas sensor, the VOCs gas detector and the hydrogen detector are installed on the mounting bracket in the box body and are electrically connected to the upper computer outside the box body through signal cables; the signal cables pass through the electrical outlet in the box body.

[0022] As a further improvement of the present utility model, the battery fixing device is in the shape of a square table and includes a square tabletop and a plurality of support feet below the tabletop.

[0023] And / or

[0024] A plurality of hooks are provided around the tabletop.

[0025] And / or

[0026] The tabletop of the battery fixing device is made of asbestos board or is provided with an asbestos board layer on the surface.

[0027] As a further improvement of the present utility model, the battery puncture mechanism is fixedly installed on a detachable equipment support; the equipment support includes a base and a gantry. The base is in a square frame shape and is provided with support feet at the bottom; the frame of the base can surround the tabletop in the battery fixing device; the gantry is vertically fixed on the base; the gantry includes two vertical rods and a cross rod. The actuator in the battery puncture mechanism is fixedly connected to the cross rod and extends downward.

[0028] As a further improvement of the present utility model, the actuator adopts an electric push rod or other electrically controlled actuators capable of telescopic movement.

[0029] As a further improvement of the present utility model, the flue gas sampling device includes a rigid container with a negative pressure inside, and the container is connected to the outlet end of the outlet valve through an airtight interface.

[0030] As a further improvement of the present utility model, the heating plate includes a cast copper panel and an electric heating unit located inside the cast copper panel.

[0031] The experimental equipment for lithium battery thermal runaway reaction provided by the present utility model has the following beneficial effects:

[0032] The present utility model provides a small device that can perform various test tasks for triggering battery thermal runaway on lithium batteries, such as overheating, puncture, short circuit, overcharging, etc. The box body in this device can provide a closed space for conducting experiments, and various action execution mechanisms, sensors, detectors and other devices related to the test tasks are installed in the closed space. Technicians can manipulate the devices inside the box body through a host computer outside the box body and automatically collect various characteristic parameters during the test.

[0033] The experimental equipment for lithium battery thermal runaway reaction provided by the present utility model has a simple structure and low cost, but has relatively rich functions and can perform various common thermal runaway test tasks. This device conducts experiments in a closed environment and allows real-time observation of the test images inside the box body through a camera, etc., with high safety. In addition, the degree of automation of the control and data collection processes of this device is relatively high and it is relatively convenient to use. Description of the Drawings

[0034] The drawings are used to provide a further understanding of the present utility model and constitute a part of the specification. Together with the embodiments of the present utility model, they are used to explain the present utility model and do not constitute a limitation to the present utility model. In the drawings:

[0035] Figure 1 is the principle framework diagram of the experimental equipment for lithium battery thermal runaway reaction provided in Embodiment 1 of the present utility model.

[0036] Figure 2 is the overall appearance diagram of the experimental equipment for lithium battery thermal runaway reaction provided in Embodiment 1 of the present utility model

[0037] Figure 3 is the partial device structure layout diagram inside the box body in Embodiment 1 of the present utility model.

[0038] Figure 4 is the assembly schematic diagram of the battery puncture mechanism and the equipment support in Embodiment 1 of the present utility model.

[0039] The labels in the figure are:

[0040] 1, electrical control device; 2, video recording device; 3, battery puncture mechanism; 4, temperature sensor; 5, heating plate; 6, gas detection kit; 7, battery fixing device; 8, outlet valve; 9, flue gas sampling device; 11, box body; 30, equipment support; 31, actuator; 32, puncture needle; 110, box door; 100, host computer; 301, base; 302, gantry. Detailed Embodiments

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model.

[0042] In the description of the present utility model, it should be noted that unless otherwise specified, the meaning of "a plurality of" is two or more; the orientation or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "top", "bottom", etc. are based on the orientation or positional relationships shown in the accompanying 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 therefore should not be construed as a limitation to the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish different objects described, and cannot be construed as indicating or implying relative importance.

[0043] Embodiment 1

[0044] This embodiment provides an experimental device for the thermal runaway reaction of a lithium battery, which is used to carry out battery thermal runaway experiments and collect experimental data of the lithium battery after thermal runaway under conditions such as heating, overcharging, short circuit, or puncture. As Figure 1 shown, the experimental device includes: a box body 11, a battery fixing device 7, a battery puncture mechanism 3, an electrical monitoring and control device 1, a heating plate 5, a video recording device 2, a temperature sensor 4, a gas detection kit 6, a flue gas sampling device 9, and a host computer 100.

[0045] Among them, as Figure 2 shown, the box body 11 is a sealed cabinet-type box body 11 and is provided with an openable box door 110 in the front. A drain valve is provided at the bottom of the box body 11; an electrical outlet is provided at the top of the back side plate of the box body 11; an air outlet valve 8 is also provided on the back of the box body 11; the air outlet valve 8 is an electrically controlled valve.

[0046] In this embodiment, the function of the box body 11 is to provide a relatively closed experimental environment. The shell of the box body 11 is made of stainless steel or other similar high-strength and corrosion-resistant materials to withstand the impact during the reaction process. In a more optimized solution, the outer shell of the box body 11 includes an inner wall and an outer wall, and a polyurethane foam layer is filled in the interlayer between the inner and outer walls. The polyurethane foam layer can reduce the heat dissipation of the battery inside the box body 11 during the experiment. The structural design of opening the door on the front side of the box body 11 can facilitate technicians to install and debug relevant internal devices and experimental instruments.

[0047] In this embodiment, a silica gel sealing ring is further provided at the edge of the box door 110; the box door 110 adopts a pressurized handle, and a locking mechanism corresponding to the position of the pressurized handle is provided at the corresponding position in the box body 11. The pressurized handle and the locking mechanism can improve the connection tightness between the box door 110 and the rest of the structure of the box body 11 and effectively withstand the impact of deflagration or explosion that may occur during the battery thermal runaway experiment.

[0048] The drain valve provided at the bottom of the box body 11 facilitates the discharge of the sewage generated during cleaning when cleaning the inside of the box body 11 after the experiment. The function of the electrical outlet is to facilitate the connection of cables to the devices inside and outside the box body 11. All cables connecting the internal and external devices pass through the electrical outlet, and a flexible structural member can also be used at the electrical outlet to achieve both sealing and allowing the cables to pass through. The gas outlet valve 8 has two functions. One is to assist the flue gas sampling device 9 to collect various battery thermal runaway gases of the parameters inside the box body 11 during the experiment for FTIR gas analysis. The other is to relieve the pressure of the environment inside the box body 11 after the experiment and reduce the possible risks when the box door 110 is opened.

[0049] In addition, in this embodiment, a mounting bracket can be provided at the top of the inner wall of the box body 11, and devices such as the video recording device 2 located inside the box body 11 and not in direct contact with the battery pack can be fixedly connected to the mounting bracket. The inner wall of the box body 11 also includes a hidden cable channel that extends from the electrical outlet at the upper part of the box body 11 to the bottom surface of the box body 11; the cables of some devices including the temperature sensor 4 and the heating plate 5 can pass through the cable channel and extend from outside the box body 11 to a position near the bottom of the box body 11 where the battery pack is installed. If necessary, rollers with locking devices can also be installed at the bottom of the box body 11 to facilitate the movement of the box body 11 and the devices inside it.

[0050] In this embodiment, the battery fixing device 7 is installed at the center of the bottom surface inside the box body 11; the battery fixing device 7 is used to fix the battery pack to be tested. In this embodiment Figure 3 In the typical structure shown, the battery fixing device 7 is in the shape of a square table, including a square tabletop and a plurality of support feet below the tabletop. In addition, a plurality of hooks are provided around the tabletop. During the experiment, the technician can place the lithium battery pack to be tested on the tabletop, and then tie the battery pack to the tabletop with a steel wire rope or other heat-resistant cables. The hooks on the side of the tabletop can be used as devices for winding or fixing the steel wire rope. In other embodiments, the technician can also design other devices that can be used to fix the battery pack and constrain the position and posture of the battery pack, and use them as the battery fixing device 7 in this embodiment.

[0051] In an optimized solution of this embodiment, the tabletop of the battery fixing device 7 is made of asbestos board or has an asbestos board layer on its surface. Asbestos board has the characteristics of heat insulation and electrical insulation. In the heating thermal runaway experiment, the heating plate 5 can be directly placed on the asbestos board in the battery fixing device 7, and then the battery is heated. The heat insulation characteristic of the asbestos board can reduce the heat loss of the heating plate 5 and improve the thermal efficiency of the experimental equipment. In addition, the asbestos board can also be used as a battery placement platform in the thermal runaway experiment caused by overcharge or short circuit, and the battery is electrically isolated from the metal box 11 or other devices by the asbestos board.

[0052] The heating plate 5 in this embodiment includes a cast copper panel and an electric heating unit located inside the cast copper panel. On the one hand, the cast copper panel can protect the electric heating unit to prevent the heating plate 5 from being damaged structurally due to the impact of battery thermal runaway. On the other hand, the excellent heat conduction performance of the cast copper panel can ensure that the surface temperature of the entire heating plate 5 is uniform when heating the battery pack, enabling the heating plate to heat the battery pack as a whole and avoiding the impact of uneven local heating on the reliability of experimental data.

[0053] The battery puncturing mechanism 3 in this embodiment is located inside the box 11 and above the battery fixing device 7. The battery puncturing mechanism 3 includes a telescopic actuator 31 and a puncturing needle 32, and the puncturing needle 32 is fixedly connected to the front end of the actuator 31. The actuator 31 is used to drive the puncturing needle 32 to pierce the battery pack downward. In the actual application process, the actuator 31 uses an electric push rod or other electrically controlled actuators 31 that can perform telescopic movement.

[0054] In the specific solution of this embodiment, the actuator 31 uses a DC electric push rod model XYDHA12 - 50 produced by Wenzhou Xinyeda Transmission Technology Co., Ltd. The working voltage of the electric push rod is DC12V, the maximum thrust is 500N, the stroke is 50mm, the motor in the actuator 31 is operated by a wired controller, the propulsion speed is 20mm / s, and the diameter of the steel needle is 6mm. The conical angle of the tip of the puncturing needle 32 is 50 degrees, and the surface of the puncturing needle 32 is smooth, without rust, oxidation layer and oil stain.

[0055] Specifically, as Figure 4 shown, the battery puncturing mechanism 3 in this embodiment is fixedly installed on a detachable equipment bracket 30; the equipment bracket 30 includes a base 301 and a gantry 302. The base 301 is in a square shape and has support feet at the bottom; the frame of the base 301 can surround the tabletop in the battery fixing device 7; the gantry 302 is vertically fixed on the base 301; the gantry 302 includes two vertical rods and a cross bar. The actuator 31 in the battery puncturing mechanism 3 is fixedly connected to the cross bar and extends downward.

[0056] In the solution of this embodiment, the battery puncture mechanism 3 is detachably installed in the box body 11 through the equipment bracket 30, which allows the user to install the mechanism in the box body 11 only when a puncture experiment is needed. When performing thermal runaway experiments such as overheating, overcharging or short circuit, the user can remove the battery puncture mechanism 3 from the box body 11.

[0057] The equipment bracket 30 for installing the battery puncture mechanism 3 provided in this embodiment adopts a frame structure that matches the shape of the battery fixing device 7. After the technician sleeved the base 301 in the equipment bracket 30 on the outer periphery of the tabletop, the relative position between the battery puncture mechanism 3 and the battery fixing device 7 can be fixed, and the battery puncture mechanism 3 is aligned with the battery pack position below. In this state, when the actuator 31 presses down, the puncture needle 32 can accurately pierce the battery pack on the battery fixing device 7.

[0058] The electrical monitoring device 1 is located outside the box body 11 and is electrically connected to the electrodes of the battery pack located in the box body 11 through a cable. The electrical monitoring device 1 is used to perform overcharging or short circuit operations on the battery pack and detect the electrical parameters during the thermal runaway experiment of the battery pack. Specifically, the electrical monitoring device of this embodiment is provided with an auxiliary power supply, a battery charge and discharge management circuit, a load, etc. Using these devices, the electrical monitoring unit can test the changes in the discharge current and discharge voltage of the battery pack under the extreme state before triggering thermal runaway. In addition, through the electrical monitoring device 1, the battery pack can also be actively triggered to overcharge and short circuit, and experimental items such as overcharge thermal runaway and short circuit thermal runaway can be implemented.

[0059] The video recording device 2 in this embodiment includes a camera and a fill light; the video recording device 2 is installed at the top of the inner wall of the box body 11, and the viewing area of the video recording device 2 is directly opposite to the lithium battery to be tested below. The video recording device 2 is used to collect the image data at the lithium battery during the thermal runaway experiment.

[0060] This embodiment uses the camera to collect the on-site pictures of the battery pack in the closed box body 11 undergoing thermal runaway, and can transmit the image data outside the box body 11, and the picture inside the box body 11 is displayed in real time through an external display, which is convenient for technicians to observe the state changes of the battery pack before and after thermal runaway. In order to avoid damage to the video recording device 2 caused by the shock wave and thermal effect generated during the thermal runaway of the battery pack, this embodiment installs the video recording device 2 at the top of the box body 11 far from the battery pack to be tested.

[0061] In some more optimized solutions, a replaceable transparent glass partition can also be provided in the box body 11 to isolate the video recording device 2 from the thermal runaway reaction chamber below, further avoiding damage to the camera and fill light in the video recording device 2. During each experiment, when the transparent partition is damaged or contaminated, it is also convenient for replacement.

[0062] In practical applications, the camera in the video recording device 2 provided in this embodiment uses an ordinary full-color camera. Specifically, a Hikvision camera module is selected as the video acquisition end. The camera has 2 million pixels, the image size is 1920*1080, the lens is 2.8mm, it uses H.265 encoding, and is powered by POE. In other embodiments, the camera can also use a binocular camera that can achieve both natural light imaging and infrared imaging. Among them, the infrared imaging camera in the binocular camera can effectively observe the heat distribution during the thermal runaway process of the battery, and can also complement the advantages of the natural light imaging camera, overcoming the disadvantage that the former is easily interfered by the strong light and smoke generated by the thermal runaway of the battery.

[0063] In this embodiment, the temperature sensor 4 is installed inside the box body 11 and is used to measure the temperature of the battery pack body and its surrounding environment. The temperature sensor 4 in this embodiment uses a K-type patch thermocouple as the sensitive element, with a measurement range of 0 to 600 °C and a measurement accuracy of 0.1 °C. The temperature sensor 4 is wrapped by pure copper material, has good thermal conductivity, and can withstand a certain amount of deformation impact caused by the thermal runaway explosion of the battery. The thermocouple outputs a millivolt signal to the temperature acquisition module. Specifically, in actual installation, this embodiment installs thermocouples in the battery pack body, the side wall of the box body 11, and the heating plate 5 respectively. The first two temperature sensors 4 are used to measure the temperature of the battery body and the ambient temperature during the electrothermal thermal runaway experiment, and the third temperature sensor 4 is used to measure the temperature of the heating plate 5 to monitor the heating temperature of the battery during the thermal runaway experiment caused by overheating.

[0064] In the solution of this embodiment, the gas detection kit 6 is installed inside the box body 11 and is used to measure the real-time concentrations of CO, H2, VOCs, and electrolyte characteristic gases inside the box body 11 during the experiment. The gas detection kit 6 includes a CO concentration sensor, an electrolyte comprehensive gas sensor, a VOCs gas detector, and a hydrogen detector. The CO concentration sensor, the electrolyte comprehensive gas sensor, the VOCs gas detector, and the hydrogen detector are installed on the mounting bracket inside the box body 11 and are electrically connected to the upper computer 100 outside the box body 11 through signal cables; the signal cables pass through the electrical outlet in the box body 11.

[0065] When a lithium iron phosphate battery undergoes thermal runaway, it will generate combustible gas H2. Since the Fourier transform infrared gas analyzer cannot detect single-atom gases, this embodiment selects a hydrogen detector to detect whether H2 is generated during the thermal runaway of the battery and to monitor its concentration change in real time. This H2 detector is produced by Henan Baoshi'an Electronic Technology Co., Ltd., with a detection principle of catalytic combustion, a detection range of 0 to 1000 ppm, a detection accuracy of 1 ppm, an input voltage of DC24V, an output interface of RS485 standard, and is converted into a USB signal through a converter and connected to the PC side to read data.

[0066] During the thermal runaway experiment, in addition to the combustible gas H2, the leaked gases before and after the thermal runaway of the lithium battery also include CO, the comprehensive gas of electrolyte leakage, VOCs, etc. In order to monitor the real-time changes of the gases inside the reaction platform in real time, a self-made composite gas detector is adopted in this embodiment. Among them, the composite gas detector is powered by direct current, the communication method is the CAN communication protocol, and the controller uploads the gas detection value through the RS485 communication method. The detector is set to sample and measure the characteristic parameters generated by the battery pack in the box 11 with a sampling period of 1 Hz. The following table is the detailed parameter table of the sensors used in the composite gas detector.

[0067] Table 1: Detailed Parameters of the Composite Gas Detector

[0068]

[0069] In this embodiment, the flue gas sampling device 9 is located outside the box 11 and is connected to the outlet valve 8; the flue gas sampling device 9 is used to collect the characteristic gases generated inside the box 11 during the experiment. Specifically, the flue gas sampling device 9 in this embodiment is essentially a rigid container with a negative pressure inside. The container is connected to the outlet end of the outlet valve 8 through an airtight interface. During the thermal runaway experiment, the air pressure in the box 11 is slightly higher than the atmospheric pressure, while the container is in a negative pressure state. Therefore, the pressure difference between the box 11 and the container is relatively large. In this state, when the technician controls the outlet valve 8 to open, the gas in the box 11 will be sucked into the container outside the box 11 under the action of pressure.

[0070] The host computer 100 in this embodiment is located outside the box 11; and is electrically connected to the actuator 31, the electrical monitoring device 1, the heating plate 5, the camera, the gas detection kit 6, the outlet valve 8, and the temperature sensor 4. The host computer 100 is the control center for controlling the operating states of each electronic control device in the entire experimental equipment during the experiment, and is also the data center for collecting the monitoring data of all sensors and detectors.

[0071] Specifically, the host computer 100 is used to issue control instructions to the actuator 31, the electrical monitoring device 1, the heating plate 5, the video recording device 2, and the outlet valve 8 to control their operating states during the thermal runaway experiment. The host computer 100 is also used to obtain the images or data collected by the electrical monitoring device 1, the video recording device 2, the gas detection kit 6, and the temperature sensor 4 during the thermal runaway experiment.

[0072] In the actual application process, the function of the control part of the host computer 100 can be realized by a programmed single-chip microcomputer, while the function of the data acquisition part is realized by computer devices such as a PC host or a server. The single-chip microcomputer is connected to the host or server through a data interface such as RS485, and communication is realized using the corresponding protocol. In the host or server of this embodiment, corresponding test cases can be pre-written. Each test case contains various program instructions corresponding to each test item. When the thermal runaway experiment starts, the host or server can issue corresponding control instructions to the single-chip microcomputer in a preset logical order, and the single-chip microcomputer controls the operation of each electronic control device to complete the specified test task.

[0073] The following combines different thermal runaway experiment items to illustrate the operation process of the experimental equipment for the lithium battery thermal runaway reaction provided by the solution of this embodiment, so as to make the functions and advantages of this product clearer.

[0074] 1. Thermal runaway caused by heating

[0075] In this test item, the technician first opens the box door 110 to take out the battery puncture mechanism 3 inside the box body 11, keeps the air outlet valve 8 closed, and installs the flue gas sampling device 9 at the outlet end of the air outlet valve 8 outside the box body 11. Then, the heating plate 5 is placed on the asbestos board in the battery fixing device 7, and the battery pack to be tested is placed on the heating plate 5. Then, the battery pack is wound with a cable so that it is constrained on the battery fixing device 7. Next, the electrical monitoring device 1 is electrically connected to the electrodes of the battery pack. Finally, the box door 110 is closed, and the battery pack heating thermal runaway experiment is executed with one key through the host computer 100.

[0076] During the experiment, the host computer 100 turns on the video recording device 2 to obtain the picture at the battery pack inside the box body 11 in real time, and turns on the heating to heat the battery pack at a preset power to cause the thermal runaway of the battery pack. At the same time, the host computer 100 collects parameters such as the voltage and current of the battery pack through the electrical monitoring device 1; measures the real-time concentrations of CO, H2, VOCs, and electrolyte characteristic gases inside the box body 11 during the experiment through the gas detection kit 6; and collects and measures the temperature of the battery pack body and its surrounding environment through the temperature sensor 4.

[0077] After the experiment, the host computer 100 turns off the electrical monitoring device 1 and the video recording device 2, opens the air outlet valve 8, and collects the gas sample produced inside the box body 11 through the flue gas sampling device 9. After the sampling is completed, the host computer 100 continuously opens the air outlet valve 8 to relieve the pressure inside the box body 11. Finally, the box door 110 is opened to tidy up and clean the inside of the box body 11.

[0078] 2. Thermal runaway caused by overcharging or short circuit

[0079] In this test item, the heating plate 5 and the exhaust valve 8 are in the closed state. The technician first opens the box door 110 to take out the battery puncture mechanism 3 in the box body 11, and installs the smoke sampling device 9 at the outlet end of the exhaust valve 8 outside the box body 11. Then, remove the heating plate 5 from the battery fixture 7, place the battery pack to be tested directly on the asbestos board in the battery fixture 7, and then wrap the battery pack with a cable so that it is constrained on the battery fixture 7. Next, electrically connect the electrical inspection and control device 1 to the electrodes of the battery pack. Finally, close the box door 110, and execute the battery pack overcharge or short circuit thermal runaway experiment with one click through the host computer 100.

[0080] During the experiment, the host computer 100 turns on the video recording device 2 to obtain the real-time image of the battery pack in the box 11, and uses the electrical inspection and control device 1 to put the battery pack in an overcharged or short-circuited state, causing thermal runaway of the battery pack. At the same time, the host computer 100 also collects parameters such as the voltage and current of the battery pack through the electrical inspection and control device 1; measures the real-time concentration of CO, H2, VOCs and electrolyte characteristic gases in the box 11 during the experiment through the gas detection kit 6; and collects and measures the temperature of the battery pack body and its surrounding environment through the temperature sensor 4.

[0081] After the experiment, the host computer 100 turns off the electrical inspection and control device 1 and the video recording device 2, and opens the air outlet valve 8 to collect the gas sample produced in the box 11 through the smoke sampling device 9. After the sampling is completed, the host computer 100 continues to open the air outlet valve 8 to release the pressure inside the box 11. Finally, the box door 110 is opened to organize and clean the inside of the box 11.

[0082] 3. Thermal runaway caused by acupuncture

[0083] In this test item, the heating plate 5 and the exhaust valves are in the closed state. The technician first opens the box door 110 to install the battery puncture mechanism 3 into the box body 11 through the equipment bracket 30, and installs the smoke sampling device 9 at the outlet end of the exhaust valve 8 outside the box body 11. Then, remove the heating plate 5 from the battery fixture 7, place the battery pack to be tested directly on the asbestos board in the battery fixture 7, and then wrap the battery pack with a cable so that it is constrained on the battery fixture 7. Next, electrically connect the electrical inspection and control device 1 to the electrodes of the battery pack. Finally, close the box door 110, and execute the battery puncture thermal runaway experiment with one click through the host computer 100.

[0084] During the experiment, the host computer 100 turns on the video recording device 2 to obtain the images at the battery pack in the box body 11 in real time. The actuator 31 presses down the acupuncture needle 32 to pierce the lower battery pack, triggering the thermal runaway of the battery pack. At the same time, the host computer 100 also collects parameters such as the voltage and current of the battery pack through the electrical monitoring device 1; measures the real-time concentrations of CO, H2, VOCs and electrolyte characteristic gases in the box body 11 during the experiment through the gas detection kit 6; and collects and measures the temperature of the battery pack body and its surrounding environment through the temperature sensor 4.

[0085] After the experiment, the host computer 100 turns off the electrical monitoring device 1 and the video recording device 2, and opens the gas outlet valve 8 to collect the gas sample produced in the box body 11 through the flue gas sampling device 9. After the sampling is completed, the host computer 100 continuously opens the gas outlet valve 8 to relieve the pressure inside the box body 11. Finally, the box door 110 is opened to tidy up and clean the inside of the box body 11.

[0086] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0087] The above-described embodiments only represent several implementation manners of the present utility model, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the utility model. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several modifications and improvements can still be made, and these all belong to the protection scope of the present utility model. Therefore, the protection scope of the present utility model shall be subject to the appended claims.

Claims

1. An experimental device for thermal runaway reaction of lithium battery, characterized in that: It is used to carry out battery thermal runaway experiments and collect experimental data after thermal runaway of lithium batteries under heating, overcharging, short circuit or puncture conditions; the experimental equipment includes: The box body adopts a sealed cabinet-type box body and is provided with an openable and closable box door in the front; a drain valve is provided at the bottom of the box body; an electrical outlet is provided at the top of the back side panel of the box body; an air outlet valve is also provided at the back of the box body; the air outlet valve adopts an electric control valve; A battery fixing device, which is installed in the center of the bottom surface of the box; the battery fixing device is used to fix the battery pack to be tested; A heating plate, located on the battery fixing device, for heating the battery pack; A battery puncture mechanism, which is located in the box and above the battery fixing device; the battery puncture mechanism includes a retractable actuator and a puncture needle, the puncture needle is fixedly connected to the front end of the actuator; the actuator is used to drive the puncture needle downward to puncture the battery pack; An electrical inspection and control device, which is located outside the box and is electrically connected to electrodes of the battery pack located in the box through cables; the electrical inspection and control device is used to overcharge or short-circuit the battery pack and detect electrical parameters during a thermal runaway experiment of the battery pack; A video recording device is mounted on the top of the inner wall of the box, and the viewing area of ​​the video recording device faces the lithium battery to be tested below; the video recording device is used to collect image data at the lithium battery during the thermal runaway experiment; A temperature sensor is installed in the box and is used to measure the temperature of the battery pack body and its surrounding environment; A gas detection kit, which is installed in the box and used to measure the real-time concentration of CO, H2, VOCs and electrolyte characteristic gases in the box during the experiment; A smoke sampling device, which is located outside the box and connected to the exhaust valve; the smoke sampling device is used to collect characteristic gases generated in the box during the experiment; A host computer is located outside the box; and is electrically connected to the actuator, electrical inspection and control device, heating plate, camera, gas detection kit, exhaust valve, and temperature sensor; the host computer is used to issue control instructions to the actuator, electrical inspection and control device, heating plate, video recording device, and exhaust valve to control their operating states during the thermal runaway experiment; the host computer is also used to obtain images or data collected by the electrical inspection and control device, video recording device, gas detection kit, and temperature sensor during the thermal runaway experiment.

2. The experimental equipment for thermal runaway reaction of lithium battery as claimed in claim 1, characterized in that: The outer shell of the box body comprises an inner wall and an outer wall, and a polyurethane foam layer is filled in the interlayer between the inner and outer walls; and / or The video recording device comprises a camera and a fill light; a mounting bracket is arranged on the top of the inner wall of the box, and the video recording device is fixedly connected to the mounting bracket.

3. The experimental equipment for thermal runaway reaction of lithium battery as claimed in claim 2, characterized in that: The inner wall of the box also includes a hidden cable channel, and the cable channel extends from the electrical outlet at the upper part of the box to the bottom surface of the box.

4. The experimental equipment for thermal runaway reaction of lithium battery as claimed in claim 1, characterized in that: A silicone sealing ring is provided at the edge of the box door; the box door adopts a pressure handle, and a locking mechanism corresponding to the position of the pressure handle is provided at a corresponding position in the box body.

5. The experimental equipment for thermal runaway reaction of lithium battery as claimed in claim 1, characterized in that: The gas detection kit includes a CO concentration sensor, an electrolyte integrated gas sensor, a VOCs gas detector and a hydrogen detector; The CO concentration sensor, electrolyte integrated gas sensor, VOCs gas detector and hydrogen detector are installed on the mounting bracket in the box, and are electrically connected to the host computer outside the box through a signal cable; the signal cable passes through the electrical outlet in the box.

6. The experimental equipment for thermal runaway reaction of lithium battery as claimed in claim 1, characterized in that: The battery fixing device is in the shape of a square table, including a square table top and a plurality of supporting legs below the table top; and / or A plurality of hooks are arranged around the table top; and / or The table top of the battery fixing device is made of asbestos board or has an asbestos board layer on the surface.

7. The experimental equipment for thermal runaway reaction of lithium battery as claimed in claim 6, characterized in that: The battery puncture mechanism is fixedly mounted on a detachable equipment bracket; the equipment bracket includes a base and a door frame; the base is in a square frame shape and is provided with supporting feet at the bottom; the frame of the base can surround the table in the battery fixing device; the door frame is vertically fixed on the base; the door frame includes two vertical rods and a horizontal rod; the actuator in the battery puncture mechanism is fixedly connected to the horizontal rod and extends downward.

8. The experimental equipment for thermal runaway reaction of lithium battery as claimed in claim 1, characterized in that: The actuator adopts an electric push rod or other electric control actuator capable of telescopic movement.

9. The experimental equipment for thermal runaway reaction of lithium battery as claimed in claim 1, characterized in that: The smoke sampling device comprises a rigid container with a negative pressure inside, and the rigid container is connected to the outlet end of the gas outlet valve through an airtight interface.

10. The experimental equipment for thermal runaway reaction of lithium battery as claimed in claim 9, characterized in that: The heating plate comprises a cast copper panel and an electric heating unit located inside the cast copper panel.

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