In a recent study, the Chair of Electrical Energy Storage Technology at TUM investigated the aging behavior of 5.4 Ah multilayer pouch cells cycled within different state-of-charge windows. Charging was performed using voltage trajectories derived from physiochemical-thermal simulations at defined constant anode potentials.
🔗 Open-access article: https://iopscience.iop.org/article/10.1149/1945-7111/ade1ff
Highlights of the study:
- Fast charging with ≈10 min for 50% ΔSoC and ≈19 min for 70% ΔSoC at beginning of life; both increase by a factor of 2–3 with aging
- High fitting accuracy in degradation mode analysis (RMSE < 4 mV at 100% SoH, < 8 mV at 70% SoH)
- Loss of lithium inventory identified as main degradation mode, linearly correlated with SoH and responsible for increased charge time due to cell balancing shifts
- Post-mortem analysis confirms further amorphization of silicon and supports degradation mode results
- Physicochemical-thermal COMSOL models, degradation analysis toolbox, and full cycling dataset openly available: https://mediatum.ub.tum.de/1766548