writer：Manman Wu, Yang Zhao, Binqiao Sun et al.
keywords：Lithium-ion batteries; Organic cathode; Covalent organic frameworks
source：期刊
specific source：Nano Energy, 2020, 70, 104498
Issue time：2020年

Organic cathode materials for lithium storage have attracted wide attention owing to their very diverse structures and largely tuned engineered molecular levels. However, it remains a great challenge to design a cathode material with simultaneously combined features of high specific capacity, cycle life and rate performance. Here, based on our proposed strategy, we design and report a BQ1-COF consisting of maximum active groups (C?O and C?N) with minimal inactive groups, which when used as cathode materials for lithium-ion batteries give a reversible capacity of 502.4 mA h g?? 1 at 0.05C, so far the highest capacity among polymer-based cathode materials. More importantly, the stable framework structure delivers an excellent capacity retention (81% after 1,000 cycles at 1.54 A g?? 1), and it is noted that the rate performance (170.7 mA h g?? 1 even at 7.73 A g?? 1) is far superior to previous related reports. These results indicate that maximizing the loading of redox active groups in

a stable network structure is an effective strategy to design organic cathode materials simultaneously with high capacity and outstanding cycle and rate performance for next generation lithium-ion batteries.