Optimization of Molecular Structure and Electrode Architecture of Anthraquinone-Containing Polymer Cathode for...

Molecular structure and electrode architecture play very important roles in electrochemical performance of polymer electrode materials for lithium-ion batteries. Here, a series of anthraquinone-containing polymers with linear (with different molecular weights (MWs)) or cross-linked polymer structures were synthesized by (living) ring-opening metatheses (co)polymerization method. The influences of the molecular structures and electrode preparation process on the architectures and electrochemical performance of polymer electrodes were systematically investigated. It was found that the low MW linear polymers suffer from severe dissolution and thus result in low initial capacity and poor cycling stability. Under optimized electrode preparation process, high MW linear polymers can be uniformly composited with conductive additives and binders and deliver stable cycling performance. Cross-linked polymer shows significantly reduced solubility but a severe aggregation problem, leading to very poor electrochemical performance. Our findings shed light on the molecular structure design and electrode preparation process of polymer electrode materials for high-performance rechargeable batteries.