On the other hand, the OTQC exhibited a distinct discharge plateau at around 3.1 V, which gradually progressed into a sloping curve. The galvanostatic measurements revealed a clear benefit of the oxidation step, which increased the voltage and the capacity of the system. OTQC reached the highest capacity of 327 mAhg -1 at 50 mAg -1 with an average voltage of 2.63 V, corresponding to one of the highest reported energy densities of 860 Whkg -1 for organic materials. In comparison, TQC reached the highest capacity of 223 mAhg -1 with an average voltage of 2.42 V. The oxidation step did not compromise the cycling stability, which demonstrated capacity retention of 82 % and 79 % after 400 cycles at 50 mAg -1 for the OTQC and TQC, respectively (Figure ). Despite possessing very high theoretical capacities based on the reduction of all the pyrazine and the quinone redox-active centers (dimer OTQC, 651 mAhg -1 , 14 e -exchange and trimer OTQC, 619 mAhg -1 , 18 e -exchange), we assume that the sloping voltage profile prevents the full capacity utilization, due to the limited stability window of the electrolyte (Figure ). A similar problem has been reported in the literature, where it was solved with the use of different binder and electrolyte systems. OTQC exhibited great rate performance, at the highest rate of 20 Ag -1 the system reached a capacity of 148 mAhg -1 (39 % of the maximum capacity) (Figure ). The system exhibited high overcharging at currents higher than 5 Ag -1 , which indicated irreversible reactions during the oxidation process (Figure ). Despite excellent long-term stability at lower rates, OTQC showed moderate cycling stability at a high current of 1 Ag -1 , delivering a capacity retention of 77 % after 800 cycles (Figure ). Two approaches were used to test the hypothesis that the cycling stability issues and overcharging observed at higher current densities were a consequence of the use of a lithium metal counter electrode. Our previous work showed that the use of organic symmetric cells can eliminate the problems associated with the metal anodes and reveal the true limits of the organic Content not peer-reviewed by ChemRxiv. License: CC BY 4.0 materials. Transferring this approach to the OTQC proved to be challenging due to the high potential and asymmetry of the voltage curves. Based on the difference between the average voltage (2.63 V) and the lower potential limit of the OTQC-Li battery (1.65 V) the voltage window of (-2 to +2V) was chosen as the best compromise in terms of the electrolyte stability and the appropriate representation of cycling in the OTQC-Li battery. The OTQC symmetric cell was constructed from an OTQC electrode discharged to 1.65 V and a pristine OTQC In contrast to the cell with lithium metal anode, the symmetric cell showed excellent cycling stability even at the high current density of 20 Ag -1 reaching a capacity retention of 94 % after 2000 cycles with coulombic efficiency close to 100 % (Figure ). To further confirm the hypothesis, we substituted the lithium metal anode with an inorganic anode material, lithiated lithium titanate (LTO), which exhibits a stable voltage plateau around 1.55 V vs. Li/Li + (Figure ). OTQC-LTO battery showed similar voltage curves as OTQC-Li battery transposed by approximately 1.55 V (Figure ). Similarly to the OTQC symmetric cell, no overcharging was observed at a high current density of 2 Ag -1 enabling stable cycling reaching a capacity retention of 88 % after 2000 cycles with coulombic efficiency close to 100 % (Figure ).