Intermolecular channel expansion induced by cation-π interactions to enhance lithium storage in a crosslinked π-conjugated organic anode

The design and synthesis of novel π-conjugated polymers receive tremendous attention in electrochemical energy storage. We report a lithium-doped crosslinked π-conjugated polymer, PTAT@LiCl, with excellent electrochemical performance as an anode material for lithium ion batteries (LIBs). Benefiting from a wider range of intermolecular channel caused by cation-π interaction inducing lithium ion insert into polymer network, the prepared PTAT@LiCl shows high capacity (892 mAh g−1, 100 mA g−1), excellent rate performance (200 mAh g−1, 4C), and outstanding cycle life (500 cycles). This work provides a new insight into the performance enhancement of organic LIBs through noncovalent cation-π (Li+-π) interaction between lithium ions and large π-conjugated aromatic ring, which are meaningful for the potential application of LIBs. Benefiting from a wider range of intermolecular channel caused by cation-π interaction inducing lithium ion insert into polymer network, the prepared PTAT@LiCl shows high performance: high capacity (892 mAh g−1, 100 mA g−1), excellent rate performance (200 mAh g−1, 4C), and outstanding cycle life (500 cycles). [Display omitted] •Preparing a novel lithium-doped crosslinked π-conjugated anode, PTAT@LiCl.•A wider range of intermolecular channel caused by cation-π interaction.•The detrimental effect from π-π stacking was effectively prevented.