An Ultrahigh Rate Ionic Liquid Dual-Ion Battery Based on a Poly(anthraquinonyl sulfide) Anode

Owing to the high theoretical capacity, sustainability, and flexible structure, organic electrode materials have been considered as a promising option for rechargeable batteries. Hence, an organic polymer molecule, poly­(anthraquinonyl sulfide) (PAQS), is introduced as the anode material for a pure ionic liquid dual-ion battery (IL-DIB). Interestingly, the battery shows excellent rate performance; even at 120 C, the capacity could reach 41.9 mA h g^–1, and a maximum discharged capacity of 101.0 mA h g^–1 is obtained at a rate of 10 C. Moreover, the properties of the battery that is charged at a high rate (40 C) and discharged at a low rate (2 C) are tested, revealing a considerable capacity (51.7 mA h g^–1) and high energy efficiency (over 97%). In addition, scanning electron microscopy (SEM) and X-ray diffraction (XRD) characterization demonstrate that both the KS6 cathode and the PAQS anode remain in their original structure well after 300 cycles. Consequently, the KS6/PAQS IL-DIB shows great potential as a supercharged energy storage device for electric vehicles, mobile phones, and laptops.