Fig. 2: Electrochemical performance comparison between SC81 and SC81-air.

a, b Charge/discharge curves of pristine SC81 (a) and SC81-air (b) with voltage ranges of 2.8–4.4 V at 0.1 C (20 mA g⁻¹) for first 3 formation cycles, and 0.5 C (100 mA g⁻¹) for the rest cycles. c, d Charge/discharge curves of pristine SC81 (c) and SC81-air (d) with voltage ranges of 2.8–4.5 V at 0.1 C (20 mA g⁻¹) for first 3 formation cycles, and 0.5 C (100 mA g⁻¹) for the rest cycles. e, f Cycle performance of pristine SC81 and SC81-air with a cutoff voltage of 4.4 V (e) and 4.5 V (f) at 0.1 C (20 mA g⁻¹) for first 3 formation cycles, and 0.5 C (100 mA g⁻¹) for the rest cycles. These electrochemical tests were performed at a temperature of 25  ±  1 °C.