TY - JOUR
T1 - Calculating Heat Release Rates from Lithium-Ion Battery Fires
T2 - A Methodology Using Digital Imaging
AU - Wise, Malcom
AU - Christensen, Paul
AU - Dickman, Neville
AU - MCDonald, Joe
AU - Mrozik, Wojciech
AU - Lambert, Simon
AU - Restuccia, Francesco
N1 - Funding Information:
Some of this work was supported by the UK's Engineering and Physical Sciences Research Council (EPSRC) and the Faraday Institution as part of its Safebatt project (FIRG028). The funders had no role in the study design, or the collation, analysis and interpretation of the data or the writing of this paper.
Publisher Copyright:
© 2023, The Author(s).
PY - 2023/9/11
Y1 - 2023/9/11
N2 - Measuring flame lengths and areas from turbulent flame flares developing from lithium-ion battery failures is complex due to the varying directions of the flares, the thin flame zone, the spatially and temporally rapid changes of the thermal runaway event, as well as the hazardous nature of the event. This paper reports a novel methodology for measuring heat release rate from flame flares resulting from thermal runaway of electric vehicle lithium-ion modules comprising eight 56.3Ah lithium nickel manganese cobalt (NMC) pouch cells using digital cameras and a newly developed numerical code to process the distortion of the flame size based on distance, direction, and shape. The model is tested with a set of experiments using lithium-ion battery packs and validated with a reference set of measurements using calibration boxes, a method commonly used in the reconstruction of flame areas. The experiments showed that the effect of calibration is large, and thus digital imaging without the appropriate calibration can give very large errors in measurement of flames. The combined imaging and processing method proposed in this work allows the determination of heat release rates from lithium-ion battery packs, one of the most challenging variables to quantify during the failure of a battery pack outside the laboratory. In the example experiment that this method was applied to, almost double the heat released was accounted for, meaning 50% of the total heat released would not have been accounted for without this image processing method.
AB - Measuring flame lengths and areas from turbulent flame flares developing from lithium-ion battery failures is complex due to the varying directions of the flares, the thin flame zone, the spatially and temporally rapid changes of the thermal runaway event, as well as the hazardous nature of the event. This paper reports a novel methodology for measuring heat release rate from flame flares resulting from thermal runaway of electric vehicle lithium-ion modules comprising eight 56.3Ah lithium nickel manganese cobalt (NMC) pouch cells using digital cameras and a newly developed numerical code to process the distortion of the flame size based on distance, direction, and shape. The model is tested with a set of experiments using lithium-ion battery packs and validated with a reference set of measurements using calibration boxes, a method commonly used in the reconstruction of flame areas. The experiments showed that the effect of calibration is large, and thus digital imaging without the appropriate calibration can give very large errors in measurement of flames. The combined imaging and processing method proposed in this work allows the determination of heat release rates from lithium-ion battery packs, one of the most challenging variables to quantify during the failure of a battery pack outside the laboratory. In the example experiment that this method was applied to, almost double the heat released was accounted for, meaning 50% of the total heat released would not have been accounted for without this image processing method.
UR - http://www.scopus.com/inward/record.url?scp=85170576219&partnerID=8YFLogxK
U2 - 10.1007/s10694-023-01484-7
DO - 10.1007/s10694-023-01484-7
M3 - Article
SN - 0015-2684
VL - 59
SP - 3565
EP - 3587
JO - FIRE TECHNOLOGY
JF - FIRE TECHNOLOGY
IS - 6
ER -
