Conjugated Copolymer Design in Phenothiazine-Based Battery Materials Enables High Mass Loading Electrodes

Organic electrode materials are considered to bepromising candidates for alternative and greener energy storagesolutions. Due to their intrinsic low conductivity, however, usuallylarge amounts of conductive additives are required for electrodefabrication. Herein, we investigate electrodes with a 90 wt % activematerial ratio and high mass loadings of up to 4.3 mg cm-2, whichshow good cycling performance because of the conjugatedcopolymer structure chosen for the phenothiazine-based activematerial. By furthermore reducing the inactive weight within thepolymer through structural modification and raising the potentialrange during constant current measurements we increased thedischarge capacity for the whole composite by a factor of 12 to0.169 mAh cm-2compared to a previous study. This studydemonstrates that conjugated organic copolymers are attractive electrode materials due to their intrinsic conductivity combined withthe presence of defined redox centers.