| 1. |
- Anderson, Johan, 1973, et al.
(författare)
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Fire Spread due to Thermal Runaway in a Lithium-ion Battery Cell
- 2014
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Ingår i: Fires in vehicles (FIVE) 2014 Conference proceedings. ; 2014, s. 267-270
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The risk of spreading of fire between Lithium-ion battery cells is assessed using Finite-Element (FE) modelling of the heat transfer initiated by a thermal runaway. The results are contrasted to experimental data where the heat release rate (HRR) is utilized as an input to the simulation. It is found that the temperature increase in a neighbouring cell can be quantitatively estimated during theearly stages of the fire taking into account the anisotropic thermal conductivity of the cells.
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| 2. |
- Anderson, Johan, 1973, et al.
(författare)
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Thermal modeling of fire propagation in lithium-ion batteries
- 2015
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Ingår i: The 24th International Technical Conference on the Enhanced Safety of Vehicles (ESV). Gothenburg, Sweden on June 8-11, 2015.
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Konferensbidrag (refereegranskat)abstract
- The objective of the present work is to assess the risk of spreading of fire between Lithium-ion battery cellsinitiated by a thermal runaway. In particular it aims at developing means to predict the temperature of cells inthe vicinity of an overheated cell during the first 5-7 minutes after the thermal event in a Li-ion cell that has anorganic based electrolyte which is flammable. Finite-Element (FE) modelling is used to compute the heattransfer between cells. The spreading model is assessed modeling a scenario where the cells are exposed to a15 kW propane burner. Two different models where utilized, one that considers the conjugate heat transferbetween the surrounding hot gases and the battery cells while the second is a thermal model where theboundary conditions are measured in a mock-up test. The results from the two models are contrasted toexperimental data where the heat release rate (HRR) is utilized as an input to the simulation. It is found thatthe temperature increase in a neighboring cell can be quantitatively estimated in certain cases during the earlystages of the fire taking into account the anisotropic thermal conductivity of the cells using the conjugate heattransfer model. Moreover, the thermal model captures the qualitative behavior of the test results, however, thetemperature increase is slower in the computational model.
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| 3. |
- Andersson, Petra, et al.
(författare)
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Investigation of fire emissions from Li-ion batteries
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report presents an investigation on gases emitted during Lithium-ion battery fires. Details of the calibration of an FTIR instrument to measure HF, POF3 and PF5 gases are provided as background to the minimum detection limits for each species. The use of FTIR in tests has been verified by repeating experiments reported in the literature. The study reports on gases emitted both after evaporation and after ignition of the electrolyte fumes. Tests were conducted where electrolyte is injected into a propane flame and the influence of the addition of water is studied. Finally three types of battery cells were burnt and emission of fluorine and/or phosphorous containing species quantified.
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| 4. |
- Andersson, Petra, et al.
(författare)
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Lion Fire: Extinguishment and mitigation of fires in Li-ion batteries at sea
- 2018
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The shipping industry is facing increasing pressure to cut emissions. Diesel-electric hybrid or fully electrical propulsion systems can offer significant savings in fuel consumption and reduce emissions. However, the use of energy storage battery systems on board vessels is introducing new fire hazards and advice on suitable fire extinguishing systems and agents is desired. In a series of tests, both total compartment application water spray and water mist systems and direct injection (using several different agents) into the module were evaluated in fire tests conducted to compare different fire extinguishing approaches for a fire in a battery cell. A test compartment was constructed to simulate a battery room and a commercially available lithium-ion (Li-ion) battery cell was positioned inside a cubic box that mimicked a battery module. By heating the battery cell, combustible gases were generated, and these gases were ignited by a pilot flame inside the simulated battery module. The tests indicated that fire extinguishment of a battery cell fire inside a battery module is unlikely when using total compartment water spray or water mist fire protection systems. The water droplets are simply not able to penetrate the battery module and reach to the seat of the fire. Direct injection of the fire extinguishing agent inside the battery module is necessary. The tests also showed that agents such as water and low-expansion foam, with a high heat capacity, provide rapid cooling and fire extinguishment. The reduced water surface tension associated with low-expansion foam may improve the possibilities for water penetration whilst agents with a high viscosity may not be able to spread to the seat of the fire. Agents with less heat capacity, such as high-expansion foam and nitrogen gas, provide less cooling but fire extinguishment can still be achieved if designed correctly.
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| 5. |
- Andersson, Petra, et al.
(författare)
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Modelling of thermal events in Lithium-ion batteries
- 2015
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Ingår i: ESFSS 2015 2nd European Symposium on Fire Safety Science. 16 - 18 June 2015 European University Cyprus, Cyprus..
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Konferensbidrag (refereegranskat)abstract
- Lithium-ion batteries are seen as part of the solution to meet the environmental concerns for many areas including the automotive sector. The Li-ion technology has many good properties such as a high energy-density but also drawbacks such as its narrow window of stable operation. If the cell is e.g. heated up it might go into a thermal runaway in which the cell rapidly heats itself up, a process that might spread also to adjacent cells. In order to investigate whether a thermal event will progress to adjacent cells, it is important to be able to model the heat transport within a battery module properly. A first attempt to model the spreading has been made using Comsol Multiphysics for a test case where one cell is exposed to a heating source and then the heating spreads to other cells.
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| 6. |
- Andersson, Petra, et al.
(författare)
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Using Fourier transform infrared spectroscopy to determine toxic gases in fires with lithium-ion batteries
- 2016
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Ingår i: Fire and Materials. - : Wiley. - 0308-0501 .- 1099-1018. ; 40:8, s. 999-1015
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Tidskriftsartikel (refereegranskat)abstract
- Batteries, in particular lithium-ion (Li-ion) batteries, are seen as an alternative to fossil fuels in the automotive sector. Li-ion batteries, however, have some safety issues including possible emissions of toxic fluorine-containing compounds during fire and other abuse situations. This paper demonstrates the possibilities to use the Fourier transform infrared technique to assess some of the most important compounds, including hydrogen fluoride and the far less often measured POF3 and PF5. The study is conducted in the cone calorimeter with different solvents used in Li-ion batteries. The measurements show that, in addition to hydrogen fluoride, with a known high toxicity, POF3 is emitted and can be quantified using Fourier transform infrared.
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| 7. |
- Bertilsson, S., et al.
(författare)
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Lithium-ion battery electrolyte emissions analyzed by coupled thermogravimetric/Fourier-transform infrared spectroscopy
- 2017
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Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753 .- 1873-2755. ; 365, s. 446-455
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Tidskriftsartikel (refereegranskat)abstract
- In the last few years the use of Li-ion batteries has increased rapidly, powering small as well as large applications, from electronic devices to power storage facilities. The Li-ion battery has, however, several safety issues regarding occasional overheating and subsequent thermal runaway. During such episodes, gas emissions from the electrolyte are of special concern because of their toxicity, flammability and the risk for gas explosion. In this work, the emissions from heated typical electrolyte components as well as from commonly used electrolytes are characterized using FT-IR spectroscopy and FT-IR coupled with thermogravimetric (TG) analysis, when heating up to 650 degrees C. The study includes the solvents EC, PC, DEC, DMC and EA in various single, binary and ternary mixtures with and without the LiPF6 salt, a commercially available electrolyte, (LP71), containing EC, DEC, DMC and LiPF6 as well as extracted electrolyte from a commercial 6.8 Ah Li-ion cell. Upon thermal heating, emissions of organic compounds and of the toxic decomposition products hydrogen fluoride (HF) and phosphoryl fluoride (POF3) were detected. The electrolyte and its components have also been extensively analyzed by means of infrared spectroscopy for identification purposes.
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| 8. |
- Fredriksson, Ingemar, 1980-, et al.
(författare)
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Microcirculatory changes in type 2 diabetes assessed with velocity resolved quantitative laser Doppler flowmetry
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The response to local heating (44oC for 20 min) was evaluated in 28 type 2 diabetes patients (DM) and 29 non-diabetes controls (ND). Microcirculatory perfusion was assessed using conventional and quantitative Laser Doppler flowmetry (cLDF and qLDF), respectively. The qLDF estimates perfusion in a physiological relevant unit (g RBC / 100 g tissue × mm/s) in a fixed output volume, separated into three velocity regions, v < 1 mm/s, 1 - 10 mm/s, and v > 10 mm/s. Perfusion in cLDF is given in arbitrary units with unknown velocity distribution and measurement volume. A significantly lower response in DM than in ND was found after heat provocation both for the initial peak and the plateau response, while no significant differences were found at baseline. The qLDF showed increased perfusion for the velocity regions 1-10 mm/s and above 10 mm/s, while no significant increase was found for v < 1 mm/s. In conclusion, we found a lowered LDF response to local heating in DM. The new qLDF method showed that the increased blood flow occurs in vessels with a velocity above 1 mm/s. Baseline qLDF-data indicated that a redistribution of flow to higher velocity regions was associated with longer DM duration and for DM a negative correlation between perfusion and BMI.
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