- Autor
- Kovachev, Georgi
- Ellersdorfer, Christian
- Gstrein, Gregor
- Hanzu, Ilie
- Wilkening, H. Martin R.
- Werling, Tobias
- Schauwecker, Florian
- Sinz, Wolfgang
- TitelSafety assessment of electrically cycled cells at high temperatures under mechanical crush loads
- Datei
- DOI10.1016/j.etran.2020.100087
- Persistent Identifier
- Erschienen ineTransportation
- Band6
- Erscheinungsjahr2020
- LicenceCC BY
- ISSN2590-1168
- Download Statistik1561
- Peer ReviewJa
- AbstractAn ageing test procedure was developed in this work in order to assess the influence of battery degradation effects, occurring during electrical cycling of lithium-ion batteries at elevated temperatures, on the electrical and mechanical properties of the cells and on their safety behaviour under mechanical quasi-static crush loading. Commercial 41 A h NMC-LMO/graphite pouch cells were charged and discharged at 60 °C for 700 cycles at 1 C in an SOC range between 10 and 90%. Electrical properties of these batteries were evaluated every 100 cycles at room temperature. By the end of the cycling procedure, a 27% reduction of the initial capacity was observed. The behaviour of the fully charged aged cells under a quasi-static mechanical load was examined in a series of indentation tests, using a flat impactor geometry. This behaviour was compared to that of fresh cells. Test results show that all investigated electrically cycled cells exhibited a slight decrease in stiffness. Aged batteries also failed at higher compressive strengths and larger deformations. Post-mortem analysis of the aged cells was performed as a next step using scanning electron microscopy and the occurred degradation effects were evaluated in order to explain the changes observed in the battery electrical and mechanical properties.
[3.73 MB]