Figure 4: Charge–discharge characteristics of the pristine and GSIR LR-NCM.

(a) First charge–discharge profiles of the pristine and GSIR LR-NCM obtained from a 2032-type coin cells at 0.05 C-rate, where 1.0 C-rate corresponds to the current density of 250 mA g⁻¹. (b) Differential capacity (dQ/dV) plots of the initial cycle curves of the pristine and GSIR LR-NCM. The inset shows the enlarged dQ/dV curves about 4.5 V. (c) Discharge-rate capacity after charging galvanostatically at 0.1 C-rate before each discharge. The capacity retention when performing charge–discharge cycles at constant 0.1 C-rate for 70 cycles after all rates tested. (d,e) Cycling performance of the pristine and GSIR LR-NCM at 55 °C by applying a constant current density of 0.5 C-rate and 1.0 C-rate (250 mA g⁻¹), respectively. The loading density of the active material on the electrode was around 5.5 mg cm⁻². It is noticeable that the electrochemical data are derived from the average value of at least five coin cells, and the errors on the specific capacity are about 3 mAh g⁻¹.