OCV measurements were carried out at temperatures of 25 °C, 15 °C, 5 °C, -5 °C at SoCs between 0% and 100% (10% intervals) in a three-electrode cell. The cell was initially charged to 100% SoC with C/5 CC CV (C/50 cut-off), then was discharged for 1 h by a C/10 CC step at 25 °C i.e. to 90% SoC. The battery was subsequently allowed to relax for 15 h at the same temperature, after which the thermal cycle (15°C, 2 h; 5 °C, 2 h; -5 °C, 2 h) was applied. This process was repeated until a final SoC of 0% was attained.