Fast Kinetic Carbon Anode Inherited and Developed from Architectural Designed Porous Aromatic Framework for Flexible Lithium Ion Micro Capacitors

Abstract Lithium ion micro capacitors (LIMCs) demonstrate competitive advantages of simultaneously high energy/power densities and long cycle life over many other micro supercapacitors and micro batteries. However, these performances are significantly determined by the carbon anode with fast Li + storage kinetics. Herein, a design strategy at the precursor side of a typical porous aromatic framework‐5 (PAF‐5) from the carbon bonding levels is proposed, and coupling with the post pyrolysis, the sp 2 / sp 3 domains ratio, interlayer spacing, and pore structure of derived carbons can be synergistically balanced. The inherited sp 2 domains and porous structure from PAF‐5 endow the derived carbon with high electron transport capability and fast Li + adsorption capacity. Meanwhile, the developed sp 3 domains and enlarged interlayer spacing also enable abundant and fast Li + intercalation contribution, giving rise to a superior rate capability (141.9 mAh g −1 at 4 A g −1 ) that is 13 times better than a commercial graphite anode. A flexible LIMCs based on this carbon anode are fabricated, and simultaneously high energy/power densities (71.1 mWh cm −3 /1.9 W cm −3 ), long cycle life (94.7% after 6,000 cycles), and flexibility are achieved, demonstrating a great feasibility of designed PAFs as the trimmed carbon anode precursors for high performance Li + storage.