Conductive Polyacrylic Acid-Polyaniline as a Multifunctional Binder for Stable Organic Quinone Electrodes of Lithium-Ion Batteries
Jing Tong, Cuiping Han, Xiaorui Hao, Xiaolu Qin, Baohua Li
Abstract
High solubility in aprotic organic electrolytes and poor electrical conductivity are the main restrictions of organic electrodes in practical application. Conductive binder contributes to the high-performance electrodes as it enables both mechanical and electronic integrity of the electrode, which have been scarcely explored for organic electrodes. Herein, a conductive interpenetrating polymeric network is synthesized through in situ polymerization of polyaniline with poly(acrylic acid) (denoted PAA-PANi), which served as a novel conductive binder for organic 2-aminoanthraquinone (AAQ) materials. The conductive PANi component enhances the electrical conductivity of the electrode. Meanwhile, the PAA component serves as the binding matrix to condense with the amino groups (−NH2) of AAQ, which therefore effectively inhibits their dissolution and maintains electrode integrity during cycling. As expected, the conductive binder exhibits both excellent electrical conductivity (10–3 S cm–1) and strong mechanical adhesion. The AAQ/reduced graphene oxide (AAQ@rGO) composite electrode prepared with the as-synthesized PAA-PANi binder delivers a high specific capacity of 126.1 mAh g–1 at 0.1 A g–1, superior rate capability (71.3 mAh g –1 at 3 A g–1), and outstanding cycling stability (2000 cycles at 1 A g–1), which greatly rivals polyvinylidene fluoride and PAA binder-based electrodes. Such a strategy points the way for the design and synthesis of conductive polymeric binders for organic electrodes, whose electrical conductivity and dissolution are massive issues.