Despite achieving a high level of capacity utilisation, the overpotential observed in the 1 M LiTFSI TEGDME electrolyte for DAAQ-TFP-COF is unusually high for anthraquinone-based materials, measuring around 210 mV (Fig. ). In contrast, when the cell is cycled in the DOL/DME solvent combination, the overpotential is 85 mV lower under identical conditions. In order to differentiate between the anode and cathode contributions to the overpotential, an electrochemical test using a cyclable symmetric cell was carried out (see ESI for experimental details). In this controlled environment, where the performance of the cell is determined solely by the electrochemical performance of DAAQ-TFP-COF electrode, the overpotential decreases to 62 mV, aligning closer to the value obtained in the DOL/DME half-cell. The differences observed between the half cell and the symmetric cell suggest that the major overpotential contribution mainly originates from the Li metal anode. The influence of the Li metal anode is also evident in the rate capability test performed in the half-cell configuration (Fig. ). The rapid capacity degradation at higher currents was again attributed to processes occurring at the Li metal anode. In contrast, DAAQ-TFP-COF demonstrated good cycling stability in the symmetric cell, retaining 85% of its initial capacity at a current density of 500 mA g -1 after 1300 cycles (Fig. ). Therefore, in addition to selecting an appropriate binder and electrolyte that maximise capacity utilisation of the active material, it is crucial to recognise the contribution of the metal anode in the 2-electrode setup and to ensure that experimental setups allow for a thorough evaluation of the COF cathode material alone as exemplified by the symmetric cell test. Ex-situ infrared (IR) spectroscopy was performed on cycled electrodes at different charge states to assess the reversibility of the electrochemical performance (Figs. and). Taking into the account the recorded voltage profiles as well as the obtained capacities, it is reasonable to assume that only the anthraquinone moieties participate in the electrochemical reaction. Several characteristic IR bands can be observed in the pristine electrode. The carbonyl stretching of the anthraquinone unit can be found at 1619 and 1673 cm -1 , whereas the carbonyl band of the TFP moiety can be observed around 1658 cm -1 in the spectrum of pristine linker (Fig. ). However, following the polymerisation process, spectral bands begin to merge, leading us to assume that TFP C=O stretching is part of a broad band appearing at 1544 cm -1 , mainly due to C=C stretching. The strong band at 1225 cm -1 is related to the C-N stretching. Throughout the reduction process, all C=O bands diminish in intensity, as shown in Figures and. Upon recharging, carbonyl bands increase in intensity, confirming the good reversibility of the electrochemical process. The strong peak at 1544 cm -1 also decreases in intensity and broadens upon discharge, indicating changes in aromaticity upon reduction. In the half-discharged electrode, a new peak is observed at 1428 cm -1 , due to the formation of -C-O -Li + . The band around 1225 cm -1 related to the C-N stretching also showed some changes in the shape and intensity of the peak on discharge, which could be related to the change in conjugation on the anthracene ring. These results are consistent with the good reversibility observed in the galvanostatic cycling.