Last data update: Apr 22, 2024. (Total: 46599 publications since 2009)
Records 1-11 (of 11 Records) |
Query Trace: Dubaniewicz M [original query] |
---|
Comparison of thermal runaway pressures within sealed enclosures for nickel manganese cobalt and iron phosphate cathode lithium-ion cells
Dubaniewicz TH , Barone TL , Brown CB , Thomas RA . J Loss Prev Process Ind 2022 76 Mining vehicle manufacturers are developing lithium-ion (Li-ion) battery electric vehicles as an alternative to diesel-powered vehicles. In gassy underground mines, explosion-proof (XP) enclosures are commonly used to enclose electrical ignition sources to prevent propagation of an internal methane-air explosion to a surrounding explosive atmosphere. Li-ion batteries can create pressurized explosions within sealed enclosures due to thermal runaway (TR). NIOSH researchers measured TR pressures of nickel manganese cobalt (NMC) cathode type 18650 Li-ion cells, model MH1, as a function of free space within sealed enclosures and observed an inverse power relationship. TR pressure-rise rates, gas quantities, and temperatures were also measured. A confined NMC cell with 92.5 mL of free space produced 232 bar of pressure, far exceeding minimum pressure containment specifications for conventional XP enclosures. Approximately 287 times the cell volume of free space would be needed to reduce the TR pressure of these cells to 8.62 barg (125 psig) per U.S. Code of Federal Regulations, Title 30, Part 18. The NMC cell TR pressures were significantly higher than those measured previously for iron phosphate cathode Li-ion cells under comparable confinement conditions. 2022 |
Lithium-ion battery explosion aerosols: Morphology and elemental composition
Barone TL , Dubaniewicz TH , Friend SA , Zlochower IA , Bugarski AD , Rayyan NS . Aerosol Sci Technol 2021 55 (10) 1183-1201 Aerosols emitted by the explosion of lithium-ion batteries were characterized to assess potential exposures. The explosions were initiated by activating thermal runaway in three commercial batteries: (1) lithium nickel manganese cobalt oxide (NMC), (2) lithium iron phosphate (LFP), and (3) lithium titanate oxide (LTO). Post-explosion aerosols were collected on anodisc filters and analyzed by scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS). The SEM and EDS analyses showed that aerosol morphologies and compositions were comparable to individual grains within the original battery materials for the NMC cell, which points to the fracture and ejection of the original battery components during the explosion. In contrast, the LFP cell emitted carbonaceous cenospheres, which suggests aerosol formation by the decomposition of organics within molten microspheres. LTO explosion aerosols showed characteristics of both types of emissions. The abundance of elements from the anode, cathode, and separator in respirable aerosols underscored the need for the selection of low-toxicity battery materials due to potential exposures in the event of battery thermal runaway. Copyright © This work was authored as part of the Contributor's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 USC. 105, no copyright protection is available for such works under US Law. |
Thermal runaway pressures of iron phosphate lithium-ion cells as a function of free space within sealed enclosures
Dubaniewicz TH , Zlochower I , Barone T , Thomas R , Yuan L . Min Metall Explor 2020 38 (1) 539-547 Mining vehicle manufacturers are developing lithium-ion (Li-ion) battery electric vehicles as an alternative to diesel-powered vehicles. In gassy underground mines, explosion-proof (XP) enclosures are commonly used to enclose electrical ignition sources to prevent propagation of an internal methane (CH4) air explosion to a surrounding explosive atmosphere. Li-ion batteries can create pressurized explosions within sealed enclosures due to thermal runaway (TR). Researchers at the National Institute for Occupational Safety and Health (NIOSH) measured TR pressures of lithium iron phosphate (LFP) cells as a function of free space within sealed enclosures and observed an inverse power relationship. A well-confined cell produced 294 bar (4260 psia) of pressure during a TR, far exceeding minimum pressure containment specifications for conventional XP enclosures. Results indicate that adding enough free space surrounding LFP cells can reduce TR pressures to levels below that expected for CH4-air ignitions. Measured TR temperatures were below the minimum autoignition temperature of CH4-air. |
Experimental study on thermal runaway and vented gases of lithium-ion cells
Yuan L , Dubaniewicz T , Zlochower I , Thomas R , Rayyan N . Process Saf Environ Prot 2020 144 186-192 Lithium-ion (Li-ion) batteries have become more prevalent in mining to power a wide range of devices from handheld tools to mobile mining equipment. However, the benefits associated with using Li-ion batteries may come with a higher risk of a fire or an explosion. The major cause for a Li-ion battery fire is thermal runaway. If unmitigated, a thermal runaway can lead to cell rupture and the venting of toxic and highly flammables gases. Those flammable gases can cause a fire or explosion if ignited. In this study, researchers from the National Institute for Occupational Safety and Health (NIOSH) conducted experiments to monitor the heating of a Li-ion cell with different battery chemistries using an accelerating rate calorimeter (ARC). Inside the ARC, the cell was exposed to increasing temperatures until it reached a thermal runaway. Samples of vented gases after the thermal runaway were collected and analyzed using a gas chromatograph. Major gas components were identified, and their concentrations were measured. The results of this study can be useful in reducing the hazard of Li-ion battery fires. |
Estimation of the critical external heat leading to the failure of lithium-ion batteries
Tang W , Tam WC , Yuan L , Dubaniewicz T , Thomas R , Soles J . Appl Therm Eng 2020 179 A detailed experimental investigation on the critical external heat leading to the failure of lithium-ion (Li-ion) batteries was conducted using an Accelerating Rate Calorimeter (ARC) at the National Institute for Occupational Safety and Health (NIOSH). Several types of commercial Li-ion batteries were selected for the study, including an iron phosphate Li-ion battery (LFP), a lithium-titanate battery (LTO), and a lithium-nickel-manganese-cobalt-oxide battery (NMC). Each battery was placed in a specially designed sealed steel canister and heated in the ARC. Battery voltage throughout the test was monitored and used to indicate the time to a battery failure. Three thermocouples, one attached to the battery surface, one measuring air temperature inside the canister, and one attached to the canister's internal surface, were used to record temperature changes during the heating tests. Different thermal behaviors were observed for the various battery types. An analytical model was developed to estimate the total external heat received by the battery using the measured temperatures. Experimental data ranked the batteries tested in terms of the heat to failure as: LFP 26,650 (11 kJ) > LFP 18650 (4.3 kJ) > NMC 18650 MH1 (3.6 kJ) ≈ LTO 18650 (3.6 kJ) > NMC 18650 HG2 (3 kJ). Total heat normalized to the battery nominal energy capacity was also calculated and ranked as: LTO 18650 ≈ LFP 26650 ≈ LFP 18650 > NMC 18650 MH1 ≈ NMC 18650 HG2. The test and analysis method developed can be extended to other types of batteries with a cylindrical shape. Results from this work provide insights to the thermal safety of Li-ion batteries and can help enhance battery thermal design and management. |
Quality assurance sampling plans in US stockpiles for personal protective equipment: A computer simulation to examine degradation rates
Dubaniewicz MT , Rottach DR , Yorio PL . Health Secur 2019 17 (4) 324-333 Medical countermeasure stockpiles in the United States are designed to support healthcare workers and the public during public health emergencies; they include supplies of personal protective equipment (PPE). As part of typical PPE manufacturing processes, appropriate test methods are used to ensure that the devices provide adequate protective performance. At the time of manufacture, performance is often measured and weighed against an objective standard of quality, resulting in a pass or fail attribute being assigned to individual PPE items and thence to production lots. Incorporating periodic performance testing for stockpiled PPE can ensure that they maintain their protective qualities and integrity over time while in storage. There is an absence of guidance regarding how to design quality assurance programs for stockpiled PPE. The applicability of the Lot Quality Assurance Sampling (LQAS) approach to stockpiled PPE was examined in a previous study that compared and contrasted different sample sizes in recovering the true percentage of defective units in large lots in the LQAS framework. The current study carries this line of inquiry forward by integrating PPE degradation over time and comparing different sampling time intervals in recovering the true underlying degradation rate. The results suggest that product degradation is more easily detected when tested at shorter time intervals and for higher degradation rates. They further suggest that sampling interval groupings can be made based on the proficiency with which they recover the true underlying degradation rate. |
Quality assurance sampling plans in US stockpiles for personal protective equipment
Yorio PL , Rottach DR , Dubaniewicz M . Health Secur 2019 17 (2) 140-151 Personal protective equipment (PPE) stockpiles in the United States were established to facilitate rapid deployment of medical assets to sites affected by public health emergencies. Large quantities of PPE were introduced into US stockpiles because of the need to protect healthcare and other professionals during these events. Because most stockpiled PPE was acquired during, or immediately following, large-scale public health events, such as pandemic influenza planning (2005-20080), SARS (2003), H1N1 (2009-10), and Ebola (2014-15), aging PPE poses a significant problem. PPE such as N95 filtering face piece respirators were not designed to be stored for long periods, and much of the currently stored PPE has exceeded its manufacturer-assigned shelf life. Given the significant investment in the procurement and storage of PPE, along with projections of consumption during public health emergencies, discarding large quantities of potentially viable PPE is not an attractive option. Although shelf-life extension programs exist for other stockpiled medical assets, no such option is currently available for stockpiled PPE. This article posits stockpile quality assurance sampling plans as a mechanism through which shelf-life extension programs for stockpiled PPE may be achieved. We discuss some of the nuances that should be considered when developing a plan tailored to stockpiles and provide basic decision tools that may be used in the context of a quality assurance program tailored to stockpiled PPE. We also explore basic information by comparing and contrasting different sample size options. |
Evaluation of fiber optic methane sensor using a smoke chamber
Li M , Dubaniewicz T , Dougherty H , Addis J . Int J Min Sci Technol 2018 28 (6) 969-974 This report presents the results of experiments to evaluate a prototype fiber optic methane monitor exposed to smoke using a smoke chamber to simulate atmospheric conditions in an underground coal mine after a fire or explosion. The experiments were conducted using test fires of different combustible sources commonly found in mines —douglas-fir wood, SBR belt, and Pittsburgh seam coal. The experiments were designed to assess the response of the fiber optic methane sensor to different contaminants, different contaminant levels and different contaminant durations produced from the test fires. Since the prototype methane monitor detects methane by measuring absorption at a specific wavelength, optical power at the absorption wavelength (1650 nm) was measured as a function of smoke concentration and duration. The other sensor response parameter-methane response times-were measured between smoke tests to assess the impact of soot accumulation on the sensor. Results indicate that the sensor screen effectively prevented smoke from obscuring the optical beam within the sensor head, with minimal impact on the system optical power budget. Methane response times increased with smoke exposure duration, attributed to soot loading on the protective screen. |
Internal short circuit and accelerated rate calorimetry tests of lithium-ion cells: Considerations for methane-air intrinsic safety and explosion proof/flameproof protection methods
Dubaniewicz TH Jr , DuCarme JP . J Loss Prev Process Ind 2016 43 575-584 Researchers with the National Institute for Occupational Safety and Health (NIOSH) studied the potential for lithium-ion cell thermal runaway from an internal short circuit in equipment for use in underground coal mines. In this third phase of the study, researchers compared plastic wedge crush-induced internal short circuit tests of selected lithium-ion cells within methane (CH4)-air mixtures with accelerated rate calorimetry tests of similar cells. Plastic wedge crush test results with metal oxide lithium-ion cells extracted from intrinsically safe evaluated equipment were mixed, with one cell model igniting the chamber atmosphere while another cell model did not. The two cells models exhibited different internal short circuit behaviors. A lithium iron phosphate (LiFePO4) cell model was tolerant to crush-induced internal short circuits within CH4-air, tested under manufacturer recommended charging conditions. Accelerating rate calorimetry tests with similar cells within a nitrogen purged 353-mL chamber produced ignitions that exceeded explosion proof and flameproof enclosure minimum internal pressure design criteria. Ignition pressures within a 20-L chamber with 6.5% CH4-air were relatively low, with much larger head space volume and less adiabatic test conditions. The literature indicates that sizeable lithium thionyl chloride (LiSOCl2) primary (non rechargeable) cell ignitions can be especially violent and toxic. Because ignition of an explosive atmosphere is expected within explosion proof or flameproof enclosures, there is a need to consider the potential for an internal explosive atmosphere ignition in combination with a lithium or lithium-ion battery thermal runaway process, and the resulting effects on the enclosure. |
Further study of the intrinsic safety of internally shorted lithium and lithium-ion cells within methane-air
Dubaniewicz Jr TH , DuCarme JP . J Loss Prev Process Ind 2014 32 165-173 National Institute for Occupational Safety and Health (NIOSH) researchers continue to study the potential for lithium and lithium-ion battery thermal runaway from an internal short circuit in equipment for use in underground coal mines. Researchers conducted cell crush tests using a plastic wedge within a 20-L explosion-containment chamber filled with 6.5% CH4-air to simulate the mining hazard. The present work extends earlier findings to include a study of LiFePO4 cells crushed while under charge, prismatic form factor LiCoO2 cells, primary spiral-wound constructed LiMnO2 cells, and crush speed influence on thermal runaway susceptibility. The plastic wedge crush was a more severe test than the flat plate crush with a prismatic format cell. Test results indicate that prismatic Saft MP 174565 LiCoO2 and primary spiral-wound Saft FRIWO M52EX LiMnO2 cells pose a CH4-air ignition hazard from internal short circuit. Under specified test conditions, A123 systems ANR26650M1A LiFePO4 cylindrical cells produced no chamber ignitions while under a charge of up to 5 A. Common spiral-wound cell separators are too thin to meet intrinsic safety standards provisions for distance through solid insulation, suggesting that a hard internal short circuit within these cells should be considered for intrinsic safety evaluation purposes, even as a non-countable fault. Observed flames from a LiMnO2 spiral-wound cell after a chamber ignition within an inert atmosphere indicate a sustained exothermic reaction within the cell. The influence of crush speed on ignitions under specified test conditions was not statistically significant. |
Are lithium ion cells intrinsically safe?
Dubaniewicz TH , DuCarme JP . IEEE Trans Ind Appl 2013 49 (6) 2451-60 National Institute for Occupational Safety and Health researchers are studying the potential for Li-ion-battery thermal runaway from an internal short circuit in equipment approved as permissible for use in underground coal mines. Researchers used a plastic wedge to induce internal short circuits for thermal runaway susceptibility evaluation purposes, which proved to be a more severe test than the flat plate method for selected Li-ion cells. Researchers conducted cell crush tests within a 20-L chamber filled with 6.5 % CH4-air to simulate the mining hazard. Results indicate that LG Chem ICR18650S2 LiCoO2 cells pose a CH4 explosion hazard from a cell internal short circuit. Under specified test conditions, A123 Systems 26650 LiFePO4 cells were safer than the LG Chem ICR18650S2 LiCoO2 cells at a conservative statistical significance level. |
- Page last reviewed:Feb 1, 2024
- Page last updated:Apr 22, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure