Battery thermal runaway gas toxicity testing device and method

Abstract

The invention provides a battery thermal runaway gas toxicity testing device and method.The device comprises a battery thermal runaway triggering container, a toxicity testing container, a gas collecting system, a data collecting system and a control system, and the battery thermal runaway triggering container is connected with a vacuumizing system and a heating system; a mouse cage is arranged in the toxicity test container, and the volume of the toxicity test container meets a standard volume threshold value; the gas collecting system comprises a pipeline, and two ends of the pipeline are respectively connected with a gas sampling port of the battery thermal runaway triggering container and a second gas inlet of the toxicity testing container; the data acquisition system comprises a temperature sensor, a pressure sensor, a gas flowmeter and a multi-gas concentration sensor, the temperature sensor and the pressure sensor are both arranged in the battery thermal runaway trigger container, the gas flowmeter is mounted on the pipeline, and the multi-gas concentration sensor is arranged in the toxicity test container; unified test and evaluation of toxicity of gas generated by thermal runaway of different types of batteries can be realized.

Description

Technical Field

[0001] The present application relates to the technical field of toxicity testing of gases generated by battery thermal runaway, and in particular to a device and method for testing the toxicity of battery thermal runaway gases. Background Art

[0002] Lithium-ion batteries can experience thermal runaway under conditions of thermal, electrical, or mechanical abuse, releasing large amounts of mixed gases. These gases are not only flammable and explosive, but also somewhat toxic: they contain asphyxiating gases such as CO and HCN, and may also contain irritants such as HF and SO2. Once the mixed gas produced by battery thermal runaway is released into a confined space, especially a small one, it can create a toxic environment over time and increase in concentration, potentially harming personnel within.

[0003] At present, the study of the toxicity of gases produced by thermal runaway of lithium-ion batteries is still in its infancy, and there are no clearly defined standard test devices and test methods. Researchers mainly use the method of triggering battery thermal runaway in the combustion chamber, collecting battery thermal runaway gases through gas hoods and pipelines, and measuring the gas concentration in the pipeline. According to the measured real-time concentration changes of asphyxiating gases and HF gases, the theoretical method given in ISO 13571 is used to calculate and judge the toxicity of the mixed gas. However, this type of research is significantly affected by different test devices. Different pipe diameters and other conditions lead to different collection concentrations, making it impossible to judge and measure toxicity under a unified standard. In addition, most of the methods used are theoretical calculations, which lack intuitiveness and accuracy. Since there are still no standardized test methods and test devices that can intuitively reflect the toxicity of battery thermal runaway gas production, it is impossible to effectively and uniformly and effectively evaluate the toxicity of battery thermal runaway gases. Summary of the Invention

[0004] This application provides a battery thermal runaway gas toxicity testing device and method to at least partially address one of the technical issues in the related art. The technical solution of this application is as follows:

[0005] According to a first aspect of an embodiment of the present application, a battery thermal runaway gas toxicity testing device is provided, comprising a battery thermal runaway trigger container, a toxicity testing container, a gas collection system, a data acquisition system, and a control system.

[0006] The battery thermal runaway trigger container is provided with a gas sampling port, and the battery thermal runaway trigger container is connected to a vacuum system and a heating system;

[0007] A mouse cage is provided in the toxicity test container, a second air inlet and a second air outlet are provided on the toxicity test container, and a second air exhaust valve is installed at the second air exhaust port; the volume of the toxicity test container meets the standard volume threshold;

[0008] The gas collection system includes a pipeline and an output solenoid valve, a flow regulating valve and a gas extraction device provided on the pipeline, wherein both ends of the pipeline are connected to the gas sampling port and the second air inlet respectively;

[0009] The data acquisition system includes a temperature sensor, a pressure sensor, a gas flow meter, and multiple gas concentration sensors. The temperature sensor and the pressure sensor are both arranged in the battery thermal runaway trigger container, the gas flow meter is installed on the pipeline, and the multiple gas concentration sensors are arranged in the toxicity test container;

[0010] The control system is connected to the data acquisition system, the stirrer, the vacuum system, the heating system, the output solenoid valve, the flow regulating valve, the second exhaust valve and the air extraction device.

[0011] In some implementations, the multiple gas concentration sensors include a carbon monoxide concentration detector, an HCN concentration detector, an HF concentration detector, and an SO2 concentration detector, and each gas concentration sensor includes a plurality of sensors that are fixed at different positions in the toxicity test container.

[0012] In some implementations, the standard volume threshold is 60L.

[0013] In some implementations, the control system includes a control cabinet and a host computer and a programmable controller therein, the host computer is connected to the programmable controller via a cable, the heating system is a laser, a first air inlet and a first exhaust port are provided on the battery thermal runaway trigger container, and an agitator is installed in the battery thermal runaway trigger container.

[0014] According to a second aspect of an embodiment of the present application, a method for testing battery thermal runaway gas toxicity is provided. The method is implemented by the battery thermal runaway gas toxicity testing device according to the first aspect, and the method includes the following steps:

[0015] Placing a battery in the battery thermal runaway trigger container, evacuating the battery thermal runaway trigger container using the vacuum pumping system, and activating the heating system to heat the battery after the battery thermal runaway trigger container reaches a vacuum environment until thermal runaway occurs in the battery; during the heating process, the control system collects pressure data in the battery thermal runaway trigger container in real time through the pressure sensor, and calculates an average gas generation rate of thermal runaway gas based on the pressure data;

[0016] When the temperature in the battery thermal runaway trigger container drops to room temperature, turning on the agitator to evenly distribute the gas in the battery thermal runaway trigger container; at the same time, placing an experimental mouse in the cage;

[0017] The output solenoid valve and the second exhaust valve are opened, and the control system controls the exhaust device and the flow regulating valve to input thermal runaway gas into the toxicity test container at the average gas production rate; during the gas input process, the average real-time concentration of multiple gases is obtained in real time by the multiple gas concentration sensors, and the effective dose percentage FED of the asphyxiating gas and the effective concentration percentage FEC of the irritating gas are calculated based on the average real-time concentration of the multiple gases; and when any value of the FED or FEC exceeds 1, the input of thermal runaway gas into the toxicity test container is stopped; and the poisoning and death of mice during the poisoning process are observed and recorded.

[0018] In some implementations, the method further includes:

[0019] The control system obtains, through the gas flow meter, the total volume of the thermal runaway gas injected into the toxicity test container when the thermal runaway gas is stopped from being injected into the toxicity test container; and calculates the basic concentration of toxicity based on the total volume of the thermal runaway gas;

[0020] Based on the basic poisoning concentration, a plurality of different set poisoning concentrations for the acute inhalation toxicity test are obtained, and target gas volumes corresponding to the plurality of different set poisoning concentrations are calculated;

[0021] An acute inhalation toxicity test is conducted for each of the multiple different set poisoning concentrations and its target gas volume; after the gas in the battery thermal runaway trigger container is evenly distributed, the thermal runaway gas of the target gas volume corresponding to the set poisoning concentration is quickly input into the toxicity test container at one time, and the mice are exposed to the poison for a preset time in the toxicity test container; the poisoning and death of the mice during the preset observation period are observed and recorded, and the median lethal concentration of the thermal runaway gas is determined based on the observation results.

[0022] In some implementations, calculating an average gas production rate of thermal runaway gas based on the pressure data includes:

[0023] Based on the pressure data, obtaining a first moment when the pressure starts to increase, a second moment when the pressure increases to a maximum point, and a third moment when the pressure stops changing;

[0024] Based on the pressure data at the third moment and in combination with the ideal gas state equation, the total volume of gas produced during the battery thermal runaway process is obtained;

[0025] Calculating the difference between the second moment and the first moment to obtain a total time of gas release during the battery thermal runaway process;

[0026] Based on the total volume of gas produced and the total time of gas release, an average gas production rate of thermal runaway gas is obtained.

[0027] In some implementations, calculating the contamination concentration based on the total volume of the thermal runaway gas includes:

[0028] Based on the total volume of the thermal runaway gas, the contamination concentration Φ is calculated using the following formula:

[0029] Φ=V gas / V3

[0030] Among them, V3 is the volume of the toxicity test container, V gas is the total volume of thermal runaway gas.

[0031] In some implementations, turning on the heating system to heat the battery until thermal runaway occurs in the battery includes:

[0032] The control system collects the real-time temperature of the battery surface through the temperature sensor and calculates the temperature change rate of the battery surface according to the real-time temperature;

[0033] When the temperature change rate reaches a temperature threshold, it is determined that thermal runaway occurs in the battery.

[0034] In some implementations, the preset duration is 1 hour and the preset observation period is 14 days.

[0035] The technical solutions provided by the embodiments of this application bring at least the following beneficial effects:

[0036] The battery thermal runaway trigger container and its auxiliary devices can control the occurrence of thermal runaway in the battery and collect the thermal runaway gases and gas production-related parameters generated by the battery thermal runaway. The gas collection system controls the volume and rate of thermal runaway gas injection into the toxicity test container. By setting a standard toxicity test container, a standardized test device for battery thermal runaway gas toxicity testing is provided. By setting a standardized, uniformly sized exposure test container and a reliable source of battery thermal runaway gas, gas toxicity evaluation is achieved under the same dimension. Standardized testing and intuitive analysis and evaluation of gas toxicity of different types of batteries can be achieved. Thermal runaway gas is injected into the toxicity test container based on the average gas production rate of the battery thermal runaway gas. The real-time gas concentrations of various gases in the toxicity test container are collected through multiple gas sensors. The toxic environment conditions achieved based on the real-time gas concentrations are calculated, and the FED or FEC reaches 1. The toxicity of the thermal runaway gas is also intuitively determined through the poisoning and death of real mice after exposure.

[0037] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0039] Figure 1 A schematic diagram of the structure of a battery thermal runaway gas toxicity testing device provided in an embodiment of the present application;

[0040] Figure 2 A flow chart of a battery thermal runaway gas toxicity testing method provided in an embodiment of the present application;

[0041] Figure 3 A flowchart of a battery thermal runaway gas toxicity testing method provided by another embodiment of the present application is shown. DETAILED DESCRIPTION

[0042] In order to enable ordinary persons in the art to better understand the technical solutions of the present disclosure, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings.

[0043] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0044] It should be noted that the terms "first", "second", etc. in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims. In addition, in the description of the present application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0045] It should be noted that in the technical solutions disclosed herein, the collection, storage, use, processing, transmission, provision and disclosure of user personal information are all carried out with the user's consent, and are in compliance with relevant laws and regulations and do not violate public order and good morals.

[0046] The following describes a battery thermal runaway gas toxicity testing device and method according to an embodiment of the present application with reference to the accompanying drawings.

[0047] Figure 1 This is a schematic diagram of the structure of a battery thermal runaway gas toxicity testing device provided in an embodiment of the present application, as shown in FIG. Figure 1 As shown, the battery thermal runaway gas toxicity testing device includes a battery thermal runaway trigger container 1, a toxicity testing container 3, a gas collection system 2, a data acquisition system and a control system.

[0048] The battery thermal runaway trigger container 1 is provided with a first air inlet 1-3, a first exhaust port, and a gas sampling port 1-5. A stirrer 1-6 is installed inside the battery thermal runaway trigger container 1. The battery thermal runaway trigger container 1 is connected to a vacuum system 1-7 and a heating system 1-8. The heating system 1-8 is a laser that uses localized laser heating to induce thermal runaway in the battery.

[0049] A cage 3-6 is provided in the toxicity test container 3. A second air inlet and a second exhaust port are provided on the toxicity test container 3. A second exhaust valve 3-5 is installed at the second exhaust port. The volume of the toxicity test container 3 meets the standard volume threshold.

[0050] The gas collection system 2 includes a pipeline and an output solenoid valve 2-1, a flow control valve 2-2 and a gas extraction device 2-4 provided on the pipeline. The two ends of the pipeline are connected to the gas sampling port 1-5 and the second gas inlet respectively;

[0051] The data acquisition system includes a temperature sensor 1-1, a pressure sensor 1-2, a gas flow meter 2-3, and multiple gas concentration sensors. The temperature sensor 1-1 and the pressure sensor 1-2 are both arranged in the battery thermal runaway trigger container 1, the gas flow meter 2-3 is installed on the pipeline, and the multiple gas concentration sensors are arranged in the toxicity test container 3;

[0052] The control system is connected to the data acquisition system, the stirrer 1-6, the vacuum system 1-7, the heating system 1-8, the output solenoid valve 2-1, the flow regulating valve 2-2, the second exhaust valve 3-5 and the exhaust device 2-4.

[0053] Thus, the control system collects the surface temperature of the battery through the temperature sensor 1-1, and determines whether the battery has thermal runaway based on the temperature change rate of the battery surface temperature; the control system collects the pressure change in the battery thermal runaway trigger container 1 through the pressure sensor 1-2, and calculates the average gas production rate of the thermal runaway gas based on the collected pressure data, so as to inject the thermal runaway gas into the toxicity test container 3 at the average gas production rate; the control system controls the volume and flow rate of the gas input into the toxicity test container 3 through the output solenoid valve 2-1, flow control valve 2-2, exhaust device 2-4 and gas flow meter 2-3 provided on the pipeline; by providing a second exhaust valve 3-5 at the bottom of the toxicity test container 3, the second exhaust valve 3-5 is opened during the process of injecting the thermal runaway gas into the toxicity test container 3 to maintain a normal pressure environment in the toxicity test container 3, and the second exhaust valve 3-5 is closed after the gas injection is completed; the average real-time concentration of various gases in the toxicity test container 3 is collected through multiple gas concentration sensors, and the gas toxicity is intuitively determined by observing the poisoning and death of mice in the cage 3-6 after being poisoned.

[0054] In some embodiments, the battery thermal runaway triggering container 1 is a steel container, the temperature sensor 1 - 1 is a thermocouple, and a first exhaust valve 1 - 4 is installed on the first exhaust port.

[0055] In some embodiments, the multiple gas concentration sensors include a carbon monoxide concentration detector 3-1, an HCN concentration detector 3-2, an HF concentration detector 3-3, and a SO2 concentration detector 3-4. Each gas concentration sensor includes multiple sensors that are fixed at different positions in the toxicity test container 3.

[0056] Therefore, multiple carbon monoxide concentration detectors 3-1, HCN concentration detectors 3-2, HF concentration detectors 3-3 and SO2 concentration detectors 3-4 are respectively set at different positions in the toxicity test container 3 to measure the real-time concentrations of different gases in the toxicity test container 3.

[0057] In some embodiments, the standard volume threshold is 60L.

[0058] In accordance with the requirements of GBT21605-2008 "Test Method for Acute Inhalation Toxicity of Chemicals" that 20 mice are exposed to the poison and each mouse consumes no less than 3L of air per hour, this embodiment standardizes the test and uniformly stipulates that the volume of the toxicity test container 3 is 60L to achieve standardized testing of gas toxicity, thereby avoiding the problem of inconsistent volume of toxicity test containers in the prior art.

[0059] In some embodiments, the control system includes a control cabinet and a host computer and a programmable controller therein, and the host computer is connected to the programmable controller via a cable.

[0060] The battery thermal runaway gas toxicity testing device of this embodiment can control the thermal runaway of the battery and collect the thermal runaway gas and gas production-related parameters generated by the battery thermal runaway through the battery thermal runaway trigger container and its auxiliary device; the volume and rate of thermal runaway gas injected into the toxicity testing container are controlled by the gas collection system; by setting a standard toxicity testing container, a standardized testing device for battery thermal runaway gas toxicity testing is provided; by setting a standardized, uniform volume contamination test container and a real and reliable source of battery thermal runaway gas, gas toxicity evaluation in the same dimension is achieved; and standardized testing and intuitive analysis and evaluation of gas production toxicity of different types of batteries can be achieved.

[0061] Based on the above embodiments, this application also provides a battery thermal runaway gas toxicity test method, such as Figure 2 As shown, the method includes the following steps:

[0062] In step S101, the battery is placed in a battery thermal runaway trigger container, and a vacuum system is used to evacuate the battery thermal runaway trigger container. After the battery thermal runaway trigger container reaches a vacuum environment, the heating system is turned on to heat the battery until thermal runaway occurs in the battery. During the heating process, the control system collects pressure data in the battery thermal runaway trigger container in real time through a pressure sensor, and calculates the average gas production rate of the thermal runaway gas based on the pressure data.

[0063] In this embodiment, before placing the battery in the battery thermal runaway trigger container, the following steps are performed: powering on the battery thermal runaway gas toxicity testing device, debugging and testing each component of the device to ensure reliable operation. Next, the battery with the fixture is placed in the battery thermal runaway trigger container, and various sensors and heating systems are connected, completing pre-test preparations.

[0064] In this embodiment, the heating system is turned on to heat the battery until thermal runaway occurs. This includes: the control system collects the real-time temperature of the battery surface through a temperature sensor, and calculates the temperature change rate of the battery surface based on the real-time temperature; when the temperature change rate reaches a temperature threshold, it is determined that thermal runaway has occurred.

[0065] As an example, the temperature threshold is 3°C / s. That is, when the temperature change rate of the battery surface is greater than 3°C / s, it is determined that the battery has thermal runaway, and the heating system is shut down and heating is no longer continued.

[0066] In this embodiment, the average gas production rate of thermal runaway gas is calculated based on pressure data, including: obtaining, based on the pressure data, a first moment when the pressure begins to increase, a second moment when the pressure reaches its highest point, and a third moment when the pressure stops changing; calculating the total volume of gas produced during the battery thermal runaway process based on the pressure data at the third moment and in combination with the ideal gas state equation; calculating the total time of gas release during the battery thermal runaway process by calculating the difference between the second moment and the first moment; and calculating the average gas production rate of thermal runaway gas based on the total gas production volume and the total time of gas release.

[0067] That is to say, during the thermal runaway of the battery, the pressure in the battery thermal runaway trigger container will gradually increase. After increasing to the highest point, the pressure will decrease and then stabilize. This embodiment calculates the average gas production rate of the thermal runaway gas when the pressure in the battery thermal runaway trigger container no longer continues to change; the total gas production volume during the battery thermal runaway process can be calculated based on the pressure data and combined with the ideal gas state equation; then, a pressure curve is obtained according to the pressure data, and the total time of gas release during the battery thermal runaway process is calculated according to the change in pressure in the pressure curve; average gas production rate = total gas production volume / total gas release time.

[0068] Step S102: When the temperature in the battery thermal runaway trigger container drops to room temperature, the stirrer is turned on to evenly distribute the gas in the battery thermal runaway trigger container; at the same time, experimental mice are placed in the cage.

[0069] Step S103, open the output solenoid valve and the second exhaust valve, and the control system inputs thermal runaway gas into the toxicity test container at an average gas production rate by controlling the exhaust device and the flow control valve; during the gas input process, the average real-time concentration of multiple gases is obtained in real time by multiple gas concentration sensors, and the effective dose percentage FED of the asphyxiating gas and the effective concentration percentage FEC of the irritating gas are calculated based on the average real-time concentration of the multiple gases; and when any value of FED or FEC exceeds 1, stop inputting the thermal runaway gas into the toxicity test container; observe and record the poisoning and death of mice during the poisoning process.

[0070] In this embodiment, FED and FEC are calculated according to the following formula in the ISO 13571 standard. That is, the concentrations of the gases CO, HCN, HF, and SO2 present in this solution are substituted into the following formula to calculate FED and FEC.

[0071]

[0072] in, is the concentration of each gas, that is is the concentration of CO gas (μL / L), is the concentration of HCN gas (μL / L), is the concentration of HF gas (μL / L), is the concentration of SO2 gas (μL / L), is the concentration of CO2 gas (L / L); Fi (μL / L) is the critical concentration of gas that poses a serious threat to escaping personnel; Δt is the time interval.

[0073] Thus, carbon monoxide (CO), HCN (HCN), HF (HF), and SO2 (SO2) concentration detectors measure the real-time concentration of gases at different locations within the toxicity test container and automatically calculate the average real-time concentration of each gas. Based on the average real-time concentrations of CO, HCN, HF, and SO2, the control system calculates the Feeding Estimation (FED) and Feeding Estimation (FEC) of each gas using standard formulas. When either the Feeding Estimation (FED) or Feeding Estimation (FEC) exceeds 1, the control system automatically stops the injection of the thermal runaway gas by controlling the output solenoid valve. Subsequently, the poisoning and mortality of mice during the exposure process are recorded and observed to visually determine the toxicity of the thermal runaway gas.

[0074] The battery thermal runaway gas toxicity testing method of this embodiment injects thermal runaway gas into a toxicity test container based on the average gas production rate of the battery thermal runaway gas, collects the real-time gas concentrations of various gases in the toxicity test container through multiple gas sensors, and calculates the toxic environmental conditions achieved based on the real-time gas concentrations, with the FED or FEC reaching 1. The toxicity of the thermal runaway gas is also intuitively determined through the poisoning and death of real mice after exposure.

[0075] On the basis of the above embodiment, that is, after step S103, the method of this embodiment further includes the following steps:

[0076] In step 201, the control system obtains the total volume of thermal runaway gas injected into the toxicity test container when the thermal runaway gas is stopped from being input into the toxicity test container through a gas flow meter; and calculates the basic concentration of toxicity based on the total volume of thermal runaway gas.

[0077] In this embodiment, based on the total volume of the thermal runaway gas, the basic contamination concentration Φ is calculated using the following formula:

[0078] Φ=V gas / V3

[0079] Among them, V3 is the volume of the toxicity test container, V gas is the total volume of thermal runaway gas.

[0080] Step 202: Based on the baseline concentration, multiple different set concentrations for the acute inhalation toxicity test are obtained, and the target gas volumes corresponding to each of the different set concentrations are calculated. After obtaining the baseline concentration, this step follows the test method specified in GBT 21605-2008, "Test Methods for Acute Inhalation Toxicity of Chemicals," using the baseline concentration as a basis to determine multiple different set concentrations corresponding to different operating conditions in the acute inhalation toxicity test. The target gas volumes corresponding to each set concentration are calculated, allowing for the subsequent multiple acute inhalation toxicity tests.

[0081] Step 203: Conduct an acute inhalation toxicity test for each of a plurality of different set poisoning concentrations and their target gas volumes. After the gas in the battery thermal runaway trigger container is evenly distributed, quickly input the target gas volume corresponding to the set poisoning concentration into the toxicity test container at one time, and allow the mice to be poisoned in the toxicity test container for a preset time. Observe and record the poisoning and death of the mice during the preset observation period, and determine the median lethal concentration of the thermal runaway gas based on the observation results.

[0082] As an example, the preset duration is 1 hour and the preset observation period is 14 days.

[0083] This example is to further determine the median lethal concentration LC of battery thermal runaway gas 50 Based on the total volume of thermal runaway gas entering the toxicity test container, recorded by the gas flowmeter when the injection of thermal runaway gas ceased in step S103, the toxic concentration under these conditions was calculated. This concentration was used as the baseline toxicity concentration. Using the test method specified in GBT21605-2008, "Test Methods for Acute Inhalation Toxicity of Chemicals," multiple sets of tests were re-conducted. Step S103 was not repeated during the test. Instead, after step S102, the target gas volume, calculated based on the set toxicity concentration, was rapidly injected into the toxicity test container all at once. Mice were then exposed to the toxicity test container for one hour, and poisoning and mortality were observed and recorded during the exposure and observation period. Based on the results, combined with the method specified in standard GBT21605-2008, the median lethal concentration (LC50) of the thermal runaway gas was determined.

[0084] The battery thermal runaway gas toxicity testing method of the embodiment of the present application further determines the median lethal concentration of the battery thermal runaway gas.

[0085] In the descriptions of the foregoing embodiments, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are mutually inconsistent.

[0086] Other embodiments of the present disclosure will readily occur to those skilled in the art after considering the specification and practicing the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the present disclosure being indicated by the following claims.

[0087] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes can be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A battery thermal runaway gas toxicity testing device, characterized in that: Including battery thermal runaway trigger container, toxicity test container, gas collection system, data acquisition system and control system, The battery thermal runaway trigger container is provided with a gas sampling port, and the battery thermal runaway trigger container is connected to a vacuum system and a heating system; A mouse cage is provided in the toxicity test container, a second air inlet and a second air outlet are provided on the toxicity test container, and a second air exhaust valve is installed at the second air exhaust port; the volume of the toxicity test container meets the standard volume threshold; The gas collection system includes a pipeline and an output solenoid valve, a flow regulating valve and a gas extraction device provided on the pipeline, wherein both ends of the pipeline are connected to the gas sampling port and the second air inlet respectively; The data acquisition system includes a temperature sensor, a pressure sensor, a gas flow meter, and multiple gas concentration sensors. The temperature sensor and the pressure sensor are both arranged in the battery thermal runaway trigger container, the gas flow meter is installed on the pipeline, and the multiple gas concentration sensors are arranged in the toxicity test container; The control system is connected to the data acquisition system, the stirrer, the vacuum system, the heating system, the output solenoid valve, the flow regulating valve, the second exhaust valve and the air extraction device.

2. The battery thermal runaway gas toxicity testing device according to claim 1, characterized in that: The multiple gas concentration sensors include a carbon monoxide concentration detector, an HCN concentration detector, an HF concentration detector and an SO2 concentration detector. Each gas concentration sensor includes a plurality of sensors that are respectively fixed at different positions in the toxicity test container.

3. The battery thermal runaway gas toxicity testing device according to claim 1, characterized in that: The standard volume threshold is 60L.

4. The battery thermal runaway gas toxicity testing device according to claim 1, characterized in that: The control system includes a control cabinet and a host computer and a programmable controller therein. The host computer is connected to the programmable controller via a cable. The heating system is a laser. A first air inlet and a first exhaust port are provided on the battery thermal runaway trigger container. An agitator is installed in the battery thermal runaway trigger container.

5. A battery thermal runaway gas toxicity testing method, characterized in that: The method is implemented by the battery thermal runaway gas toxicity testing device according to any one of claims 1 to 4, and the method comprises the following steps: Placing a battery in the battery thermal runaway trigger container, evacuating the battery thermal runaway trigger container using the vacuum pumping system, and activating the heating system to heat the battery after the battery thermal runaway trigger container reaches a vacuum environment until thermal runaway occurs in the battery; during the heating process, the control system collects pressure data in the battery thermal runaway trigger container in real time through the pressure sensor, and calculates an average gas generation rate of thermal runaway gas based on the pressure data; When the temperature in the battery thermal runaway trigger container drops to room temperature, turning on the agitator to evenly distribute the gas in the battery thermal runaway trigger container; at the same time, placing an experimental mouse in the cage; The output solenoid valve and the second exhaust valve are opened, and the control system controls the exhaust device and the flow regulating valve to input thermal runaway gas into the toxicity test container at the average gas production rate; during the gas input process, the average real-time concentration of multiple gases is obtained in real time by the multiple gas concentration sensors, and the effective dose percentage FED of the asphyxiating gas and the effective concentration percentage FEC of the irritating gas are calculated based on the average real-time concentration of the multiple gases; and when any value of the FED or FEC exceeds 1, the input of thermal runaway gas into the toxicity test container is stopped; and the poisoning and death of mice during the poisoning process are observed and recorded.

6. The method according to claim 5, characterized in that The method further comprises: The control system obtains, through the gas flow meter, the total volume of the thermal runaway gas injected into the toxicity test container when the thermal runaway gas is stopped from being injected into the toxicity test container; and calculates the basic concentration of toxicity based on the total volume of the thermal runaway gas; Based on the basic poisoning concentration, a plurality of different set poisoning concentrations for the acute inhalation toxicity test are obtained, and target gas volumes corresponding to the plurality of different set poisoning concentrations are calculated; An acute inhalation toxicity test is conducted for each of the multiple different set poisoning concentrations and its target gas volume; after the gas in the battery thermal runaway trigger container is evenly distributed, the thermal runaway gas of the target gas volume corresponding to the set poisoning concentration is quickly input into the toxicity test container at one time, and the mice are exposed to the poison for a preset time in the toxicity test container; the poisoning and death of the mice during the preset observation period are observed and recorded, and the median lethal concentration of the thermal runaway gas is determined based on the observation results.

7. The method according to claim 5, characterized in that The calculating the average gas production rate of the thermal runaway gas based on the pressure data includes: Based on the pressure data, obtaining a first moment when the pressure starts to increase, a second moment when the pressure increases to a maximum point, and a third moment when the pressure stops changing; Based on the pressure data at the third moment and in combination with the ideal gas state equation, the total volume of gas produced during the battery thermal runaway process is obtained; Calculating the difference between the second moment and the first moment to obtain a total time of gas release during the battery thermal runaway process; Based on the total volume of gas produced and the total time of gas release, an average gas production rate of thermal runaway gas is obtained.

8. The method according to claim 5, characterized in that The calculating of the contamination concentration based on the total volume of the thermal runaway gas includes: Based on the total volume of the thermal runaway gas, the contamination concentration Φ is calculated using the following formula: Φ=V gas / V3 Among them, V3 is the volume of the toxicity test container, V gas is the total volume of thermal runaway gas.

9. The method according to claim 5, characterized in that The step of activating the heating system to heat the battery until thermal runaway occurs in the battery comprises: The control system collects the real-time temperature of the battery surface through the temperature sensor and calculates the temperature change rate of the battery surface according to the real-time temperature; When the temperature change rate reaches a temperature threshold, it is determined that thermal runaway occurs in the battery.

10. The method according to claim 6, characterized in that The preset duration is 1 hour, and the preset observation period is 14 days.

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