Redox-active catechols are bioinspired precursors for ortho-quinones that are characterized by higher discharge potentials than para-quinones, the latter being extensively used as organic cathode materials for lithium ion batteries (LIBs). Here, this study demonstrates that the rational molecular design of copolymers bearing catechol- and Li ion-conducting anionic pendants endow redox-active polymers (RAPs) with ultrarobust electrochemical energy storage features when combined to carbon nanotubes as a flexible, binder-, and metal current collector-free buckypaper electrode. The importance of the structure and functionality of the RAPs on the battery performances in LIBs is discussed. The structure-optimized RAPs can store high-capacities of 360 mA h g at 5C and 320 mA h g at 30C in LIBs. The high ion and electron mobilities within the buckypaper also enable to register 96 mA h g (24% capacity retention) at an extreme C-rate of 600C (6 s for total discharge). Moreover, excellent cyclability is noted with a capacity retention of 98% over 3400 cycles at 30C. The high capacity, superior active-material utilization, ultralong cyclability, and excellent rate performances of RAPs-based electrode clearly rival most of the state-of-the-art Li ion organic cathodes, and opens up new horizons for large-scalable fabrication of electrode materials for ultrarobust Li storage.

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In this paper, we report the synthesis Via the Grignard metathesis method (GRIM) of donor/ acceptor double cable copolymers with diblock and random sequences, where the conjugated polythiophene backbone is substituted with hexyl chains and with alkyl chains bearing fullerene. First, the monomers 2,5-dibromo-3-hexylthiophene and 2,5-dibromo-3-(1,3-dioxa-2-octyl)thiophene were randomly copolymerized and yielded after the grafting of fullerene C 60 the double cable CoPTR-C. Second, the same monomers were used to synthesize a diblock copolymer with a block made from a random copolymerization of both monomers while the second block is pure poly(3-hexylthiophene). After the grafting of fullerene, the block double cable CoPTBl-C was obtained. Both double cable copolymers were investigated through various characterization methods. NMR 1D and 2D experiments allowed the full structural characterization and the determination of the final composition of the copolymers. The thermal behavior was investigated by TGA and DSC measurements, indicating that the incorporation of fullerene increased the thermal stability of the materials. The optical properties of these double cable copolymers were investigated by UV-visible absorption and fluorescence spectroscopy. The results showed no interaction at ground-state between the donor and acceptor moieties and a quenching of fluorescence of the polythiophene main chains in solution. AFM analysis on drop-casted films showed the dependence of the morphology of the double cable systems (random or diblock) on the aggregation.