Fabrication of a Practical and Polymer-Rich Organic Radical Polymer Electrode and its Rate Dependence

A practical and polymer-rich organic radical cathode that contains 80 wt.-% poly(4-vinyloxy-2,2,6,6-tetramethylpiperidine-N-oxyl) (PTVE) and 15 wt.-% vapor-grown carbon fiber (VGCF) has been fabricated. The PTVE/VGCF composite electrode shows a reversible redox peak at 3.56 V (vs Li/Li(+)) in cyclic voltammetry. A coin-type cell with the PTVE/VGCF composite electrode as the cathode and lithium metal as the anode has also been fabricated and used for charge/discharge measurements. When the cell was discharged at 0.3 mA . cm(-2) (1 C), a capacity of 104 mAh . g(-1), which is 77% of PTVE's theoretical capacity (135 mAh . g(-1)), was obtained. When it was discharged at 9.0 mA . cm(-2) (30 C), its capacity was 52% of the capacity it had when it was discharged at 0.3 mA . cm(-2) (1 C). Even when discharged at 2 4 mA . cm(-2) (80 C), it surprisingly had 32% of the capacity it had when discharged at 0.3 mA . cm(-2). The observed rate dependence shows that the polymer-rich electrode could discharge over 50% of the cell capacity in two minutes and over 30% within one minute.