I have prepared the Fe2O3@graphene nanocomposites using commercial Fe2O3 (size = 200 nm) and commercial graphene oxide (GO) via HI reduction. Afterward, I have prepared the active electrode film by combining the 8:2 ratio of Fe2O3@graphene: SWCNT via vacuum filtering followed by drying in a vacuum oven at 120 oC for overnight. I am using the HS Flat cell for testing the Li-ion capacitor and preparing each electrode under the glove box. By making the Li-ion capacitor half cell (Anode, Fe2O3@graphene//Li), I am using Cu foil as the current collector, cell guard 3501 as a separator and 1 M LiPF6 in EC:DEC:DMC as electrolyte (about 0.5 mL). I have run the CV in the potential window of 0.05 to 3 V for 10 cycles. I have seen good CVs up to 7 cycles (see Figure 1) and afterward, every time I am seeing the loss of CV features from 8 to 10 cycles (see Figure 2). CV peak jumps up at about 2.5 V in 8th cycles and the 9th cycle is by about 2.3 V and the 10th cycle is by 2.2 V. The peak suddenly jumps after the 8th cycle and in further cycles, the CV jump moving towards the lower potential side. I have also given 1-10 cycles CV (see Figure 3). I am seeing the same situation about 5-6 times and it's repeating every time. Anyone, Can you help me to understand these features?

Thanks in advance.