As the energy density of lithium-ion cells and batteries increases, controlling the outcomes of thermal runaway becomes more challenging. If the high rate of gas generation during thermal runaway is not adequately vented, commercial cell designs can rupture and explode, presenting serious safety concerns. Here, ultra-high-speed synchrotron X-ray imaging is used at >20 000 frames per second to characterize the venting processes of six different 18650 cell designs undergoing thermal runaway. For the first time, the mechanisms that lead to the most catastrophic type of cell failure, rupture, and explosion are identified and elucidated in detail. The practical application of the technique is highlighted by evaluating a novel 18650 cell design with a second vent at the base, which is shown to avoid the critical stages that lead to rupture. The insights yielded in this study shed new light on battery failure and are expected to guide the development of safer commercial cell designs.
Bibliographical noteFunding Information:
The authors would like to acknowledge funding from the EPSRC (EP/ N032888/1 and EP/M009394/1), the Royal Academy of Engineering, the STFC (ST/N002385/1), and the UK National Measurement System. These experiments were performed between beamlines ID19 at the ESRF (Grenoble, France) and I12 at Diamond Light Source (Harwell, UK). Finally, the authors would like to acknowledge the help and support from Sandeep Yayathi from the NASA Johnson Space Center.
© 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Copyright 2018 Elsevier B.V., All rights reserved.
- high-speed imaging
- Li-ion batteries
- thermal runaway
- X-ray CT
ASJC Scopus subject areas
- Medicine (miscellaneous)
- Chemical Engineering(all)
- Biochemistry, Genetics and Molecular Biology (miscellaneous)
- Materials Science(all)
- Physics and Astronomy(all)