Name: in situ gas analysis and fire characterization of lithium-ion cells during thermal runaway using an environmental chamber
Uploaded: 2023-03-31T15:00:00
Description: Watch this Scientific Journal Video about In Situ Gas Analysis and Fire Characterization of Lithium-Ion Cells During Thermal Runaway Using an Environmental Chamber at JoVE.com

This study is supported by the UL Research Institutes. All battery cells in this work were conditioned and prepared in Prof. Chris Yuan&#39;s lab at Case Western Reserve University (CWRU). The test chamber is on loan to CWRU from NASA Glenn Research Center. We received tremendous support on the FTIR gas analyzer from a former PhD student, Dr. Yumi Matsuyama at CWRU, and technical support on the H2 sensor from Jeff Tucker, Brandon Wicks, and Brian Engle from Amphenol Advanced Sensors. We sincerely appreciate the support from Pushkal Kannan and Boyu Wang at CWRU. We would also like to acknowledge the technical discussions with Alexandra Schraiber from UL Solutions.

1. Startup of the FTIR gas analyzer
NOTE: The procedures can be different for different brands and models of the FTIR gas analyzer. The following procedure is for the specific gas analyzer used in this work.
<ol>
	<li>Install a new filter or a clean filter (i.e., one that has been cleaned in an ultrasonic bath) in the filter/valve unit (see Figure 1 and Figure 2).</li>
	<li>Open the valve of the nitrogen cylinder co...

<ol>
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P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+analysis+of+thermal+runaway+and+propagation+in+lithium-ion+battery+modules.">Experimental analysis of thermal runaway and propagation in lithium-ion battery modules.</a> Journal of The Electrochemical Society. 162 (9), 1905 (2015).</li><li>Ghiji, M., Edmonds, S., Moinuddin, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+of+experimental+and+numerical+studies+of+lithium+ion+battery+fires.">A review of experimental and numerical studies of lithium ion battery fires.</a> Applied Sciences. 11 (3), 1247 (2021).</li><li>Jhu, C. Y., Wang, Y. W., Shu, C. M., Chang, J. C., Wu, H. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal+explosion+hazards+on+18650+lithium+ion+batteries+with+a+VSP2+adiabatic+calorimeter.">Thermal explosion hazards on 18650 lithium ion batteries with a VSP2 adiabatic calorimeter.</a> Journal of Hazardous Materials. 192 (1), 99-107 (2011).</li><li>Roth, E. P., Doughty, D. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal+abuse+performance+of+high-power+18650+Li-ion+cells.">Thermal abuse performance of high-power 18650 Li-ion cells.</a> Journal of Power Sources. 128 (2), 308-318 (2004).</li><li>Golubkov, A. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal-runaway+experiments+on+consumer+Li-ion+batteries+with+metal-oxide+and+olivin-type+cathodes.">Thermal-runaway experiments on consumer Li-ion batteries with metal-oxide and olivin-type cathodes.</a> RSC Advances. 4 (7), 3633-3642 (2013).</li><li>Joshi, T., Azam, S., Lopez, C., Kinyon, S., Jeevarajan, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Safety+of+lithium-ion+cells+and+batteries+at+different+states-of-charge.">Safety of lithium-ion cells and batteries at different states-of-charge.</a> Journal of The Electrochemical Society. 167 (14), 140547 (2020).</li><li>Ribi&#232;re, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigation+on+the+fire-induced+hazards+of+Li-ion+battery+cells+by+fire+calorimetry.">Investigation on the fire-induced hazards of Li-ion battery cells by fire calorimetry.</a> Energy &amp; Environmental Science. 5 (1), 5271-5280 (2012).</li><li>Chen, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigation+on+the+thermal+hazards+of+18650+lithium+ion+batteries+by+fire+calorimeter.">Investigation on the thermal hazards of 18650 lithium ion batteries by fire calorimeter.</a> Journal of Thermal Analysis and Calorimetry. 122 (2), 755-763 (2015).</li><li>Fu, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+experimental+study+on+burning+behaviors+of+18650+lithium+ion+batteries+using+a+cone+calorimeter.">An experimental study on burning behaviors of 18650 lithium ion batteries using a cone calorimeter.</a> Journal of Power Sources. 273, 216-222 (2015).</li><li>Ouyang, D., He, Y., Chen, M., Liu, J., Wang, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+study+on+the+thermal+behaviors+of+lithium-ion+batteries+under+discharge+and+overcharge+conditions.">Experimental study on the thermal behaviors of lithium-ion batteries under discharge and overcharge conditions.</a> Journal of Thermal Analysis and Calorimetry. 132 (1), 65-75 (2018).</li><li>Said, A. O., Lee, C., Liu, X., Wu, Z., Stoliarov, S. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simultaneous+measurement+of+multiple+thermal+hazards+associated+with+a+failure+of+prismatic+lithium+ion+battery.">Simultaneous measurement of multiple thermal hazards associated with a failure of prismatic lithium ion battery.</a> Proceedings of the Combustion Institute. 37 (3), 4173-4180 (2019).</li><li>Quintiere, J. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+methods+to+measure+the+energetics+of+a+lithium+ion+battery+in+thermal+runaway.">On methods to measure the energetics of a lithium ion battery in thermal runaway.</a> Fire Safety Journal. 111, 102911 (2020).</li><li>Chen, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+of+lithium-ion+battery+safety+concerns:+The+issues,+strategies,+and+testing+standards.">A review of lithium-ion battery safety concerns: The issues, strategies, and testing standards.</a> Journal of Energy Chemistry. 59, 83-99 (2021).</li><li>Kennedy, R. W., Marr, K. C., Ezekoye, O. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gas+release+rates+and+properties+from+Lithium+Cobalt+Oxide+lithium+ion+battery+arrays.">Gas release rates and properties from Lithium Cobalt Oxide lithium ion battery arrays.</a> Journal of Power Sourcres. 487, 229388 (2021).</li><li>Essl, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comprehensive+hazard+analysis+of+failing+automotive+Lithium-ion+batteries+in+overtemperature+experiments.">Comprehensive hazard analysis of failing automotive Lithium-ion batteries in overtemperature experiments.</a> Batteries. 6 (2), 30 (2020).</li><li>. Fire characterization and gas analysis of lithium-ion batteries during thermal runaway Available from: <a target="_blank" href="https://ttu-ir.tdl.org/handle/2346/89734">https://ttu-ir.tdl.org/handle/2346/89734</a> (2022)</li><li>FTIR Toxity Test. Fire Testing Technology Available from: <a target="_blank" href="https://www.fire-testing.com/ftir-toxicity-test/">https://www.fire-testing.com/ftir-toxicity-test/</a> (2022)</li></ol>

The most critical steps in the protocol are those concerning the toxic gases released in the LIB thermal runaway. The leak test in step 3.11 needs to be carefully performed to ensure that the toxic gases are confined in the chamber during the experiments. The chamber gas clean-up procedures (steps 7.1-7.14) must also be properly done to mitigate the hazard from the toxic gases. Toxic gases may constitute only a small fraction of the vent gas during LIB thermal runaway. However, even very low concentrations of some toxic ...

In the last few decades, lithium-ion batteries (LIBs) have gained popularity and benefited from tremendous technological advancements. Owing to various advantages (e.g., high energy density, low maintenance, low self-discharge and charge times, and long lifespan), the LIB has been considered a promising energy storage technology and extensively used in various applications, such as large energy storage systems (ESSs), electric vehicles (EVs), and portable electronic devices. While the global demand for LIB cells is expected to double from 725 GWh in 2020 to 1,500 GWh in 20301, there has been a substantial increase in fires and explosions related to LIBs in recent years2. These accidents demonstrate the high risks associated with LIBs, raising concerns regarding their large-scale utilization. To mitigate these concerns, it is crucial to gain a thorough understanding of the process of LIB thermal runaway leading to fires.
Previous accidents have revealed that LIB cells fail when the cell electrochemistry is disrupted by overheating in abnormal operating circumstances (such as external short circuit, rapid discharge, overcharging, and physical damage) or due to manufacturing defects and poor design2,3,4. These events lead to the decomposition of the solid-electrolyte interface (SEI), stimulating highly exothermic chemical reactions between electrode materials and electrolytes. When the heat produced in these reactions exceeds that being dissipated, it results in rapid self-heating of the cells, also known as thermal runaway. Internal temperature and pressure can continue rising until built-up pressure causes the battery to rupture and release flammable, toxic gases at high speed. In a multi-cell battery configuration, a thermal runaway in a single cell, if not controlled, can lead to thermal runaway propagation to other cells and incidents of fire and explosion at catastrophic levels, especially in enclosed spaces with limited ventilation. This poses significant threats to human safety and structures.
In the past few decades, a number of studies have been carried out to investigate the thermal runaway reactions of LIBs leading to the combustion of organic electrolytes inside the battery and the release of flammable gases under different heating conditions2,5,6,7,8,9,10,11,12. For example, Jhu et al.10 demonstrated the hazardous nature of charged cylindrical LIBs compared to uncharged ones using an adiabatic calorimeter. Many other studies focused on the thermal runaway behavior of LIBs at different state-of-charges (SOCs). For example, Joshi et al.13 investigated the thermal runaway of various types of commercial LIBs (cylindrical and pouch) at different SOCs. It was noticed that cells at higher SOCs had a higher chance of undergoing thermal runaway compared to those at lower SOCs. In addition, the minimum SOC for a thermal runaway to occur varied with the cell formats and chemistries. Roth et al.11 tested cylindrical LIBs in an accelerating rate calorimeter (ARC) and observed that, as the SOC increased, the onset temperature of thermal runaway decreased and the acceleration rate increased. Golubkov et al.12 developed a custom-designed test stand and showed that the maximum surface temperature of cylindrical LIBs could be as high as 850 &#176;C. Ribi&#232;re et al.14 used a fire propagation apparatus to investigate the fire-induced hazards of pouch LIBs and noticed that the heat release rate (HRR) and toxic gas production varied significantly with the cell SOC. Chen et al.15 studied the fire behaviors of two different 18650 LIBs (LiCoO2 and LiFePO4) at different SOCs, using a custom-made in situ calorimeter. HRR, mass loss, and maximum surface temperature were found to increase with SOC. It was also demonstrated that the risk of explosion was higher for a fully charged lithium cobalt oxide (LiCoO2) cathode 18650 cell compared to a lithium iron phosphate (LiFePO2) cathode 18650 cell. Fu et al.16 and Quang et al.17 conducted fire experiments on LIBs (at 0%-100% SOCs) using a cone calorimeter. It was observed that LIBs at a higher SOC resulted in higher fire hazards due to shorter lengths of time to ignition and explosion, higher HRR, higher surface temperature, and higher CO and CO2 emissions.
To summarize, previous studies using different calorimeters18,19&#160;(ARC, adiabatic calorimetry, C80 calorimetry, and modified bomb calorimetry) have provided abundant data on the electrochemical and thermal processes associated with LIB thermal runaway and fires (e.g., HRR, compositions of the vented gases) and their dependencies on the SOC, battery chemistry, and incident heat flux2,3,7,20. However, most of these methods were designed originally for conventional solid combustibles (e.g., cellulose samples, plastic) and provide limited information when applied to LIB fires. While some previous tests measured the HRR and the total energy generated from chemical reactions, the kinetics aspects of post-thermal runaway fires were not fully addressed.
The severity of hazards during thermal runaway is mainly dependent on the nature and composition of the gases released2,5. Therefore, it is important to characterize the released gases, the venting rate, and their dependence on the SOC. Some previous studies measured the vent gas compositions of LIB thermal runaway in an inert environment (e.g., in nitrogen or argon)12,21,22; the fire component during the thermal runaway was excluded. In addition, these measurements were mostly performed post-experiments (instead of in situ). Evolutions of vent gas composition during and post-thermal runaway, especially those involving fires and toxic gases, remained under-explored.
It is known that thermal runaway disrupts the electrochemistry of the battery and impacts the cell voltage and temperature. A comprehensive test to characterize the thermal runaway process of the LIB should, therefore, provide simultaneous measurement of the temperature, mass, voltage, and vented gases (rate and composition). This has not been achieved in a single setup in the previous studies. In this study, a new apparatus and test protocol are developed to collect time-resolved data on the cell information, gas compositions, and fire characteristics during and post-thermal runaway of LIB cells23. The test apparatus is shown in Figure 1A. A large (~600 L) environmental chamber is used to confine the thermal runaway event. The chamber is equipped with a pressure relief valve (with a set gauge pressure at 0.5 psig) to prevent pressure rise in the chamber. A Fourier transform infrared (FTIR) gas analyzer is connected to the chamber for in situ gas sampling throughout the test. It detects 21 gas species (H2O, CO2, CO, NO, NO2, N2O, SO2, HCl, HCN, HBr, HF, NH3, C2H4, C2H6, C3H8, C6H14, CH4, HCHO, C6H6O, C3H4O, and COF2). The FTIR sampling rate is 0.25 Hz. In addition, a standalone hydrogen sensor is installed inside the chamber near the FTIR sampling port to record the H2 concentration. Two pumps (a 1.3 cfm chemical-resistant diaphragm pump and a 0.5 hp vacuum pump) are installed in the chamber exhaust line. After each experiment, a chamber clean-up procedure is followed to filter and pump the chamber gas directly to the building exhaust line.
In each experiment, the cell is set up inside the chamber in a sample holder (Figure 1B). Thermal runaway is triggered by a proportional-integral-derivative (PID)-controlled electric heating tape at a constant heating rate of 10 &#176;C/min. Cell surface temperatures are recorded by thermocouples in three different locations along the length of the cell. The mass loss of the cell is measured by a mass balance. The chamber pressure is monitored by a pressure transducer. The cell voltage and the power input (voltage and current) to the heating tape are also recorded. All sensor readings (thermocouples, mass loss, cell voltage, heating tape current, and voltage) are collected by a custom data acquisition program at a rate of 2 Hz. Lastly, two camcorders (1920 pixel x 1080 pixel resolution) are used to record the entire process of the experiments from two different angles.
The objective of developing this new test method is twofold: 1) to characterize the smoke and fire behaviors associated with LIB thermal runaway and 2) to provide time-resolved experimental data that enables the development of high-validity numerical models for battery fires. The long-term goal is to advance the understanding of how thermal runaway propagates between cells in a battery pack and how a battery fire scales up when going from single cells to multi-cell batteries. Ultimately, this will help improve guidelines and protocols for storing and transporting LIBs safely.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Balance</td>
			<td>A&#38;D</td>
			<td>EJ-6100</td>
			<td></td>
		</tr>
		<tr>
			<td>Carbon filter</td>
			<td>Whatman</td>
			<td>WHA67041500</td>
			<td></td>
		</tr>
		<tr>
			<td>Current transducer</td>
			<td>NK Technologies</td>
			<td>AT1-010-000-FT</td>
			<td></td>
		</tr>
		<tr>
			<td>Front camera</td>
			<td>Sony</td>
			<td>FDR-AX53</td>
			<td></td>
		</tr>
		<tr>
			<td>FTIR gas analyzer</td>
			<td>Fire Testing Technology</td>
			<td>Protea atmosFIR AFS-A-15</td>
			<td></td>
		</tr>
		<tr>
			<td>Heating tape (1.00&#34; x 2.00&#34;)</td>
			<td>Birk Manufacturing, Inc.</td>
			<td>BK3512-19.6-L24-03</td>
			<td></td>
		</tr>
		<tr>
			<td>High-temperature resistant tape</td>
			<td>Kapton</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Hydrogen sensor</td>
			<td>Amphenol</td>
			<td>AX220135</td>
			<td></td>
		</tr>
		<tr>
			<td>K-type, thermocouple</td>
			<td>Omega</td>
			<td>KMQSS-020U-12</td>
			<td></td>
		</tr>
		<tr>
			<td>LabVIEW</td>
			<td>National Instruments</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Matlab</td>
			<td>MathWorks</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>NI-9213</td>
			<td>National Instruments</td>
			<td>NI-9213</td>
			<td></td>
		</tr>
		<tr>
			<td>NI-9219</td>
			<td>National Instruments</td>
			<td>NI-9219</td>
			<td></td>
		</tr>
		<tr>
			<td>NI-cDAQ-9174</td>
			<td>National Instruments</td>
			<td>NI-cDAQ-9174</td>
			<td></td>
		</tr>
		<tr>
			<td>NI-USB-6009</td>
			<td>National Instruments</td>
			<td>NI-USB-6009</td>
			<td></td>
		</tr>
		<tr>
			<td>PID controller</td>
			<td>Omega</td>
			<td>CN8200</td>
			<td></td>
		</tr>
		<tr>
			<td>PILOT5000 Chemical Resistant Diaphragm Vacuum Pump</td>
			<td>The Lab Depot</td>
			<td>TLD5000</td>
			<td></td>
		</tr>
		<tr>
			<td>Pressure relief valve</td>
			<td>Straval</td>
			<td>RVL20-10T-N4675</td>
			<td></td>
		</tr>
		<tr>
			<td>Pressure Transmitter</td>
			<td>Keller</td>
			<td>0308.01601.081303.02</td>
			<td></td>
		</tr>
		<tr>
			<td>Pure Nickel Strip (0.1x5x100mm 99.6% Nickel)</td>
			<td>U.S. Solid Product</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Respirator</td>
			<td>McMaster</td>
			<td>55865T52</td>
			<td></td>
		</tr>
		<tr>
			<td>Respirator Cartridge</td>
			<td>Honeywell&#160;</td>
			<td>75Scp100L</td>
			<td></td>
		</tr>
		<tr>
			<td>Rotary vane vacuum pump (0.5 hp)</td>
			<td>Alcatel</td>
			<td>Pascal 2010</td>
			<td></td>
		</tr>
		<tr>
			<td>Side camera</td>
			<td>Sony</td>
			<td>HDR-CX110</td>
			<td></td>
		</tr>
		<tr>
			<td>Spot Welder</td>
			<td>SUNKKO</td>
			<td>737G+</td>
			<td></td>
		</tr>
		<tr>
			<td>TeamViewer</td>
			<td>TeamViewer</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Voltage transducer</td>
			<td>CR Magnetics Inc.</td>
			<td>CR4510-50</td>
			<td></td>
		</tr>
	</tbody>
</table>

in situ gas analysis and fire characterization of lithium-ion cells during thermal runaway using an environmental chamber

An experimental apparatus and a standard operating procedure (SOP) are developed to collect time-resolved data on the gas compositions and fire characteristics during and post-thermal runaway of lithium-ion battery (LIB) cells. A 18650 cylindrical cell is conditioned to a desired state-of-charge (SOC; 30%, 50%, 75%, and 100%) before each experiment. The conditioned cell is forced into a thermal runaway by an electrical heating tape at a constant heating rate (10 &#176;C/min) in an environmental chamber (volume: ~600 L). The chamber is connected to a Fourier transform infrared (FTIR) gas analyzer for real-time concentration measurements. Two camcorders are used to record major events, such as cell venting, thermal runaway, and the subsequent burning process. The conditions of the cell, such as surface temperature, mass loss, and voltage, are also recorded. With the data obtained, cell pseudo-properties, venting gas compositions, and venting mass rate can be deduced as functions of cell temperature and cell SOC. While the test procedure is developed for a single cylindrical cell, it can be readily extended to test different cell formats and study fire propagation between multiple cells. The collected experimental data can also be used for the development of numerical models for LIB fires.

Videos representing typical thermal runaway processes with and without fires are included in Supplementary File 1 and Supplementary File 2, respectively. Key events are depicted in Figure 5. As the cell temperature is raised (to ~110-130 &#176;C), the cell starts swelling, indicating the buildup of the internal pressure (caused by the vaporization of electrolytes and the thermal expansion of gases inside the cell2). This is followed b...

Watch this Scientific Journal Video about In Situ Gas Analysis and Fire Characterization of Lithium-Ion Cells During Thermal Runaway Using an Environmental Chamber at JoVE.com

In Situ Gas Analysis and Fire Characterization of Lithium-Ion Cells During Thermal Runaway Using an Environmental Chamber

Here, we describe a test procedure developed to characterize thermal runaway and fires in lithium-ion cells through in situ measurements of various parameters in an environmental chamber.

In Situ Gas Analysis and Fire Characterization of Lithium-Ion Cells During Thermal Runaway Using an Environmental Chamber

An experimental apparatus and a standard operating procedure (SOP) are developed to collect time-resolved data on the gas compositions and fire ...

Thermal runaway in lithium-ion batteries occurs due to several causes, which can also result in very different worst case outcomes. In this method, we are trying to simulate a catastrophic hazard in a single cell, and the protocol has been shown to provide consistency in results for the simulation of the type of hazard we want to create. The main advantage of this test procedure is that it measures various parameters in situ in one single test.The time result data comprehensively characterizes the transient event of lithium-ion battery thermal runaway and fires. This experiment requires a synchronization of data acquisition from many sensors, FDIR, and video recording. The operator has to follow the standard operating procedure to operate multiple devices step-by-step correctly.This ensures the success of experiments with consistent results and without potential hazards to personnel and devices. Demonstrating the procedure will be Pushkal Kannan, a PD student, and Dr.Ankit Sharma, a post-doctoral researcher from my lab. To begin, install a new or clean filter in the filter valve unit.Open the valve of the nitrogen cylinder connected to the gas analyzer, and adjust the nitrogen flow rate to 150 to 250 cubic centimeters per minute. With a cell preparation, measure the initial voltage and mass of the cell with a precision of 0.01 grams, and record them on the experiment log sheet. Attach a heating tape to the center of the cell.Ensure that the heating tape wires point toward the negative side of the cell. Take a picture of the cell with the tape. Attach three thermocouples to the cell surface, one near the positive terminal, one in the middle, and one at the bottom near the negative terminal of the cell using high temperature resistant tape.Use the thermocouple near the positive terminal to control the heating rate through the proportional integral derivative, or PID. All three thermocouples should be located five millimeters away from the edge of the heating tape. Take a picture of the cell with a ruler to confirm the distance from the heating tape.Spot weld nickel tabs to the positive and negative terminals of the cell for the cell voltage measurement, then load the cell on the cell holder. Place the cell and the cell holder on the mass balance in the chamber. Connect the thermocouple connectors, heating tape, and nickel tabs to the chamber feed-through plugs and wires.Turn on the PID controller for the heating tape, and set up the heating profile. Connect the cables for the PID controller, data acquisition, and the mass balance to a laptop, and start the data acquisition program on the laptop. Make sure all the sensor readings shown in the data acquisition program are reasonable.After checking the measurements, turn off the data acquisition program. Adjust the front and side view camcorder settings, manual white balance, manual focus, auto exposure, auto iris, and auto shutter speed. Make sure that the camcorder battery is full.Position the front view camcorder on a tripod outside the chamber, start recording on the side view camcorder, and place it inside a protection box in the chamber. After checking the side view camcorder angle and view, lock the protection box. Close the chamber, and ensure all the screws on the cover plates are tightly fastened.Use the vacuum or diaphragm pump to conduct a leak check, and change the FTIR intake from ambient air to the chamber. Then connect the FTIR return line to the chamber. Set the PID controller to ramp soak mode, and turn off the light in the room and the LED light in the chamber.Start the front view camcorder recording, and then record the following startup process to synchronize the data acquisition and video recording. Start the data recording and the data acquisition program on the laptop. Start the PID ramp soak mode at 10 seconds on the data acquisition program timer, turn on the chamber LED light, and start the FTIR recording.Position the front view camcorder on the tripod, and continue recording the experiment. Move to a different room, and continue monitoring the data acquisition panel on the laptop through a remote controlled desktop program. When thermal runaway occurs, or after the PID controller has maintained the cell temperature at 200 degrees Celsius for 60 minutes, turn off the power to the heating tape, and set the PID controller to standby mode.End the experiment and data recording when all three thermocouple readings become lower than 40 degrees Celsius. Purge the FTIR gas analyzer with nitrogen to clean the tube in the analyzer for around 15 minutes. After purging, stop the FTIR measurement.Before the chamber cleanup vacuuming procedure, check if the FTIR sampling intake line is closed or open to the ambient air. Select ambient air on the Protea Analyser Software, or PAS-Pro Software, or shut down the FTIR entirely. Open valve one to prepare for partially vacuuming the chamber using the chemical resistant diaphragm pump, and run the diaphragm pump until the chamber pressure drops to 9.7 pounds per square inch absolute.Turn off the diaphragm pump, and close valve one, then open valve three to fill the chamber with ambient air. Close valve three when the chamber pressure recovers to the ambient pressure. After lowering the concentration of toxic gases by partially vacuuming the chamber with the diaphragm pump, run a rotary vein pump until the chamber pressure drops to 4.7 pounds per square inch absolute to remove the rest of the toxic gases.Open the chamber, and retrieve the camcorder and the cell. Take photos before, during, and after taking the cell off the cell holder. Weigh the cell, and record the post-test mass of the cell.Finally, post-process the collected data, and generate plots to visualize the time evolution of all measurements. The cell temperature and mass loss data obtained for an 18650 cylindrical cell at 75%state of charge is shown in this figure. The mass loss indicates two distinct gas release periods, one during cell venting, and the other during thermal runaway.The concentrations of major hydrocarbon and toxic gas species are shown here. The recorded current and voltage supplied to the heating tape can be used to calculate the power input to the cell. The representative data for voltage and current supplied to the heating tape and calculated energy and power supplied to the heating tape are presented here.The most important factor here is to ensure safety during and post each experiment. The experiment must prevent an external short circuit of the test cell. And the other critical factors are confirming that the cell SoC and the heating rates are verified to be correct before the test.It is also critical to seal the chamber completely to confine the exhaust of toxic gases, and follow the cleanup procedure exactly to remove the gases in a safe manner. The test procedure can be extended to study fire application in different cell formats and modules, advancing our understanding of thermal runaway and battery fire scaling in multi-cell batteries. The comprehensive time result data collected in this test procedure enables the development of future models and theories of lithium-ion batteries.It will also help to understand how battery fire scales up.

in-situ-gas-analysis-fire-characterization-lithium-ion-cells-during

Research

JoVE Journal

Engineering

Construction and Testing of Coin Cells of Lithium Ion Batteries

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime. Lithium ion batteries have also been considered to be used in electric and hybrid vehicles1 or even electrical grid stabilization systems2. All these applications simulate a dramatic increase in the research and development of battery materials3-7, including new materials3,8, doping9, nanostructuring10-13, coatings or surface modifications14-17 and novel binders18. Consequently, an increasing number of physicists, chemists and materials scientists have recently ventured into this area. Coin cells are widely used in research laboratories to test new battery materials; even for the research and development that target large-scale and high-power applications, small coin cells are often used to test the capacities and rate capabilities of new materials in the initial stage. 
 In 2010, we started a National Science Foundation (NSF) sponsored research project to investigate the surface adsorption and disordering in battery materials (grant no. DMR-1006515). In the initial stage of this project, we have struggled to learn the techniques of assembling and testing coin cells, which cannot be achieved without numerous help of other researchers in other universities (through frequent calls, email exchanges and two site visits). Thus, we feel that it is beneficial to document, by both text and video, a protocol of assembling and testing a coin cell, which will help other new researchers in this field. This effort represents the "Broader Impact" activities of our NSF project, and it will also help to educate and inspire students.
In this video article, we document a protocol to assemble a CR2032 coin cell with a LiCoO2 working electrode, a Li counter electrode, and (the mostly commonly used) polyvinylidene fluoride (PVDF) binder. To ensure new learners to readily repeat the protocol, we keep the protocol as specific and explicit as we can. However, it is important to note that in specific research and development work, many parameters adopted here can be varied. First, one can make coin cells of different sizes and test the working electrode against a counter electrode other than Li. Second, the amounts of C black and binder added into the working electrodes are often varied to suit the particular purpose of research; for example, large amounts of C black or even inert powder were added to the working electrode to test the "intrinsic" performance of cathode materials14. Third, better binders (other than PVDF) have also developed and used18. Finally, other types of electrolytes (instead of LiPF6) can also be used; in fact, certain high-voltage electrode materials will require the uses of special electrolytes7.

A protocol to construct and test coin cells of lithium ion batteries is described. The specific procedures of making a working electrode, preparing a counter electrode, assembling a cell inside a glovebox and testing the cell are presented.

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime.  Lithium ion ...

Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques

Intercalation compounds such as transition metal oxides or phosphates are the most commonly used electrode materials in Li-ion and Na-ion batteries. During insertion or removal of alkali metal ions, the redox states of transition metals in the compounds change and structural transformations such as phase transitions and/or lattice parameter increases or decreases occur. These behaviors in turn determine important characteristics of the batteries such as the potential profiles, rate capabilities, and cycle lives. The extremely bright and tunable x-rays produced by synchrotron radiation allow rapid acquisition of high-resolution data that provide information about these processes. Transformations in the bulk materials, such as phase transitions, can be directly observed using X-ray diffraction (XRD), while X-ray absorption spectroscopy (XAS) gives information about the local electronic and geometric structures (e.g.&#160;changes in redox states and bond lengths). In situ experiments carried out on operating cells are particularly useful because they allow direct correlation between the electrochemical and structural properties of the materials. These experiments are time-consuming and can be challenging to design due to the reactivity and air-sensitivity of the alkali metal anodes used in the half-cell configurations, and/or the possibility of signal interference from other cell components and hardware. For these reasons, it is appropriate to carry out ex situ experiments (e.g.&#160;on electrodes harvested from partially charged or cycled cells) in some cases. Here, we present detailed protocols for the preparation of both ex situ and in situ samples for experiments involving synchrotron radiation and demonstrate how these experiments are done.

We describe the use of synchrotron X-ray absorption spectroscopy (XAS) and X-ray diffraction (XRD) techniques to probe details of intercalation/deintercalation processes in electrode materials for Li-ion and Na-ion batteries. Both in situ and ex situ experiments are used to understand structural behavior relevant to the operation of devices

Intercalation compounds such as transition metal oxides or phosphates are the most commonly used electrode materials in Li-ion and Na-ion batteries. ...

Characterization of Thermal Transport in One-dimensional Solid Materials

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials, including conductive, semi-conductive or nonconductive one-dimensional structures. This technique broadens the measurement scope of materials (conductive and nonconductive) and improves the accuracy and stability. If the sample (especially biomaterials, such as human head hair, spider silk, and silkworm silk) is not conductive, it will be coated with a gold layer to make it electronically conductive. The effect of parasitic conduction and radiative losses on the thermal diffusivity can be subtracted during data processing. Then the real thermal conductivity can be calculated with the given value of volume-based specific heat (&#961;cp), which can be obtained from calibration, noncontact photo-thermal technique or measuring the density and specific heat separately. In this work, human head hair samples are used to show how to set up the experiment, process the experimental data, and subtract the effect of parasitic conduction and radiative losses.

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials.

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials, including ...

In Situ Neutron Powder Diffraction Using Custom-made Lithium-ion Batteries

Li-ion batteries are widely used in portable electronic devices and are considered as promising candidates for higher-energy applications such as electric vehicles.1,2 However, many challenges, such as energy density and battery lifetimes, need to be overcome before this particular battery technology can be widely implemented in such applications.3 This research is challenging, and we outline a method to address these challenges using in situ NPD to probe the crystal structure of electrodes undergoing electrochemical cycling (charge/discharge) in a battery. NPD data help determine the underlying structural mechanism responsible for a range of electrode properties, and this information can direct the development of better electrodes and batteries.
We briefly review six types of battery designs custom-made for NPD experiments and detail the method to construct the &#8216;roll-over&#8217; cell that we have successfully used on the high-intensity NPD instrument, WOMBAT, at the Australian Nuclear Science and Technology Organisation (ANSTO). The design considerations and materials used for cell construction are discussed in conjunction with aspects of the actual in situ NPD experiment and initial directions are presented on how to analyze such complex in situ data.

In Situ Neutron Powder Diffraction Using Custom-made Lithium-ion Batteries

We describe the design and construction of an electrochemical cell for the examination of electrode materials using in situ neutron powder diffraction (NPD). We briefly comment on alternate in situ NPD cell designs and discuss methods for the analysis of the corresponding in situ NPD data produced using this cell.

Li-ion batteries are widely used in portable electronic devices and are considered as promising candidates for higher-energy applications such as electric ...

Non-aqueous Electrode Processing and Construction of Lithium-ion Coin Cells

Research into new and improved materials to be utilized in lithium-ion batteries (LIB) necessitates an experimental counterpart to any computational analysis. Testing of lithium-ion batteries in an academic setting has taken on several forms, but at the most basic level lies the coin cell construction. In traditional LIB electrode preparation, a multi-phase slurry composed of active material, binder, and conductive additive is cast out onto a substrate. An electrode disc can then be punched from the dried sheet and used in the construction of a coin cell for electrochemical evaluation. Utilization of the potential of the active material in a battery is critically dependent on the microstructure of the electrode, as an appropriate distribution of the primary components are crucial to ensuring optimal electrical conductivity, porosity, and tortuosity, such that electrochemical and transport interaction is optimized. Processing steps ranging from the combination of dry powder, wet mixing, and drying can all critically affect multi-phase interactions that influence the microstructure formation. Electrochemical probing necessitates the construction of electrodes and coin cells with the utmost care and precision. This paper aims at providing a step-by-step guide of non-aqueous electrode processing and coin cell construction for lithium-ion batteries within an academic setting and with emphasis on deciphering the influence of drying and calendaring.

Non-aqueous electrode processing is central to the construction of coin cells and the evaluation of new electrode chemistries for lithium-ion batteries. A step-by-step guide to the basic practices needed as an electrochemical engineer working with batteries in an academic experimental setting is furnished.

Research into new and improved materials to be utilized in lithium-ion batteries (LIB) necessitates an experimental counterpart to any computational ...

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices have used devices prepared by spin coating, a process that is not amenable to large-scale fabrication. This mismatch in device fabrication makes it difficult to translate quantitative results obtained in the laboratory to the commercial level, making optimization difficult. Using a mini-slot die coater, this mismatch can be resolved by translating the commercial process to the laboratory and characterizing the structure formation in the active layer of the device in real time and in situ as films are coated onto a substrate. The evolution of the morphology was characterized under different conditions, allowing us to propose a mechanism by which the structures form and grow. This mini-slot die coater offers a simple, convenient, material efficient route by which the morphology in the active layer can be optimized under industrially relevant conditions. The goal of this protocol is to show experimental details of how a solar cell device is fabricated using a mini-slot die coater and technical details of running in situ structure characterization using the mini-slot die coater.

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Here, we present a protocol to fabricate organic thin film solar cells using a mini-slot die coater and related in-line structure characterizations using synchrotron scattering techniques.

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices ...

Experimental Methodology for Estimation of Local Heat Fluxes and Burning Rates in Steady Laminar Boundary Layer Diffusion Flames

Modeling the realistic burning behavior of condensed-phase fuels has remained out of reach, in part because of an inability to resolve the complex interactions occurring at the interface between gas-phase flames and condensed-phase fuels. The current research provides a technique to explore the dynamic relationship between a combustible condensed fuel surface and gas-phase flames in laminar boundary layers. Experiments have previously been conducted in both forced and free convective environments over both solid and liquid fuels. A unique methodology, based on the Reynolds Analogy, was used to estimate local mass burning rates and flame heat fluxes for these laminar boundary layer diffusion flames utilizing local temperature gradients at the fuel surface. Local mass burning rates and convective and radiative heat feedback from the flames were measured in both the pyrolysis and plume regions by using temperature gradients mapped near the wall by a two-axis traverse system. These experiments are time-consuming and can be challenging to design as the condensed fuel surface burns steadily for only a limited period of time following ignition. The temperature profiles near the fuel surface need to be mapped during steady burning of a condensed fuel surface at a very high spatial resolution in order to capture reasonable estimates of local temperature gradients. Careful corrections for radiative heat losses from the thermocouples are also essential for accurate measurements. For these reasons, the whole experimental setup needs to be automated with a computer-controlled traverse mechanism, eliminating most errors due to positioning of a micro-thermocouple. An outline of steps to reproducibly capture near-wall temperature gradients and use them to assess local burning rates and heat fluxes is provided.

We describe the use of micro-thermocouples to estimate local temperature gradients in steady laminar boundary layer diffusion flames. By extension of the Reynolds Analogy, local temperature gradients can be further used to estimate the local mass burning rates and heat fluxes in such flames with high accuracy.

Modeling the realistic burning behavior of condensed-phase fuels has remained out of reach, in part because of an inability to resolve the complex ...

Focused Ion Beam Fabrication of LiPON-based Solid-state Lithium-ion Nanobatteries for In Situ Testing

Solid-state electrolytes are a promising replacement for current organic liquid electrolytes, enabling higher energy densities and improved safety of lithium-ion (Li-ion) batteries. However, a number of setbacks prevent their integration into commercial devices. The main limiting factor is due to nanoscale phenomena occurring at the electrode/electrolyte interfaces, ultimately leading to degradation of battery operation. These key problems are highly challenging to observe and characterize as these batteries contain multiple buried interfaces. One approach for direct observation of interfacial phenomena in thin film batteries is through the fabrication of electrochemically active nanobatteries by a focused ion beam (FIB). As such, a reliable technique to fabricate nanobatteries was developed and demonstrated in recent work. Herein, a detailed protocol with a step-by-step process is presented to enable the reproduction of this nanobattery fabrication process. In particular, this technique was applied to a thin film battery consisting of LiCoO2/LiPON/a-Si, and has further been previously demonstrated by in situ cycling within a transmission electron microscope.

Focused Ion Beam Fabrication of LiPON-based Solid-state Lithium-ion Nanobatteries for In Situ Testing

A protocol for the fabrication of electrochemically active LiPON-based solid-state lithium-ion nanobatteries using a focused ion beam is presented.

Solid-state electrolytes are a promising replacement for current organic liquid electrolytes, enabling higher energy densities and improved safety of ...

Experimental Procedure for Laboratory Studies of In Situ Burning : Flammability and Burning Efficiency of Crude Oil

A new method for the simultaneous study of the flammability and burning efficiency of fresh and weathered crude oil through two experimental laboratory setups is presented. The experiments are easily repeatable compared to operational scale experiments (pool diameter &#8805;2 m), while still featuring quite realistic in situ burning conditions of crude oil on water. Experimental conditions include a flowing water sub-layer that cools the oil slick and an external heat flux (up to 50 kW/m2) that simulates the higher heat feedback to the fuel surface in operational scale crude oil pool fires. These conditions enable a controlled laboratory study of the burning efficiency of crude oil pool fires that are equivalent to operational scale experiments. The method also provides quantitative data on the requirements for igniting crude oils in terms of the critical heat flux, ignition delay time as a function of the incident heat flux, the surface temperature upon ignition, and the thermal inertia. This type of data can be used to determine the required strength and duration of an ignition source to ignite a certain type of fresh or weathered crude oil. The main limitation of the method is that the cooling effect of the flowing water sub-layer on the burning crude oil as a function of the external heat flux has not been fully quantified. Experimental results clearly showed that the flowing water sub-layer does improve how representative this setup is of in situ burning conditions, but to what extent this representation is accurate is currently uncertain. The method nevertheless features the most realistic in situ burning laboratory conditions currently available for simultaneously studying the flammability and burning efficiency of crude oil on water.

Experimental Procedure for Laboratory Studies of In Situ Burning : Flammability and Burning Efficiency of Crude Oil

Here, we present a protocol to simultaneously study the flammability and burning efficiency of fresh and weathered crude oil under conditions that simulate in situ burning operations on the sea.

A new method for the simultaneous study of the flammability and burning efficiency of fresh and weathered crude oil through two experimental laboratory ...

Three-electrode Coin Cell Preparation and Electrodeposition Analytics for Lithium-ion Batteries

As lithium-ion batteries find use in high energy and power applications, such as in electric and hybrid-electric vehicles, monitoring the degradation and subsequent safety issues becomes increasingly important. In a Li-ion cell setup, the voltage measurement across the positive and negative terminals inherently includes the effect of the cathode and anode which are coupled and sum to the total cell performance. Accordingly, the ability to monitor the degradation aspects associated with a specific electrode is extremely difficult because the electrodes are fundamentally coupled. A three-electrode setup can overcome this problem. By introducing a third (reference) electrode, the influence of each electrode can be decoupled, and the electrochemical properties can be measured independently. The reference electrode (RE) must have a stable potential that can then be calibrated against a known reference, for example, lithium metal. The three-electrode cell can be used to run electrochemical tests such as cycling, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). Three-electrode cell EIS measurements can elucidate the contribution of individual electrode impedance to the full cell. In addition, monitoring the anode potential allows the detection of electrodeposition due to lithium plating, which can cause safety concerns. This is especially important for the fast charging of Li-ion batteries in electric vehicles. In order to monitor and characterize the safety and degradation aspects of an electrochemical cell, a three-electrode setup can prove invaluable. This paper aims to provide a guide to constructing a three-electrode coin cell setup using the 2032-coin cell architecture, which is easy to produce, reliable, and cost-effective.

Three-electrode cells are useful in studying the electrochemistry of lithium-ion batteries. Such an electrochemical setup allows the phenomena associated with the cathode and anode to be decoupled and examined independently. Here, we present a guide for construction and use of a three-electrode coin cell with emphasis on lithium plating analytics.

As lithium-ion batteries find use in high energy and power applications, such as in electric and hybrid-electric vehicles, monitoring the degradation and ...