Functional Separator With A Lightweight Carbon-Coating For Stable, High-Capacity Organic Lithium Batteries

A major challenge facing organic rechargeable batteries is the problem of the dissolution and shuttle effect of organic cathodes in aprotic electrolytes, resulting in limited capacity, low cyclability and poor rate performance. Herein, a functional polypropylene separator coated with Ketjen black (C@PP) was introduced to tackle the shuttle issue. The inhibitory effect on quinone shuttle correlates with physical barrier and excellent adsorption of Ketjen black (KB), as proved by a series of spectroscopy studies. With the C@PP separator, quinone cathodes including pentacene-5,7,12,14-tetrone (PT), Calix[4] quinone (C4Q), 9,10-anthraquinone (AQ) and 9,10-phenanthrenequinone (PQ) demonstrated high reversible capacity and excellent cyclic stability in Li storage. Specially, PT exhibited high capacity (>300 mAh g-1), long-term cyclability (-0.06% decay per cycle over 400 cycles at 0.5 C) and fast kinetic (5 C). C4Q delivered high energy density (782 Wh kg-1) and respectable cyclability (-60% after 500 cycles). This facile and versatile separator modifying strategy opens a new avenue for solving quinone electrode issues to achieve high-performance OLBs.