A Sulfur Heterocyclic Quinone Cathode and a Multifunctional Binder for a High‐Performance Rechargeable Lithium‐Ion Battery. Issue 22 (15th April 2016)

• Record Type: Journal Article
• Authors: Ma, Ting; Zhao, Qing; Wang, Jianbin; Pan, Zeng; Chen, Jun
• Is Part Of: Angewandte Chemie international edition. Volume 55:Issue 22(2016)
• Page Start: 6428
• Page End: 6432
• Publication Date: 2016-04-15
• Subjects: lithium-ion batteries -- molecular design -- multifunctional binders -- noncovalent interactions -- sulfur heterocyclic quinones; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201601119
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: We report a rational design of a sulfur heterocyclic quinone (dibenzo[b, i]thianthrene‐5, 7, 12, 14‐tetraone=DTT) used as a cathode (uptake of four lithium ions to form Li4 DTT) and a conductive polymer [poly(3, 4‐ethylenedioxythiophene):poly(styrenesulfonate)=PEDOT:PSS) used as a binder for a high‐performance rechargeable lithium‐ion battery. Because of the reduced energy level of the lowest unoccupied molecular orbital (LUMO) caused by the introduced S atoms, the initial Li‐ion intercalation potential of DTT is 2.89 V, which is 0.3 V higher than that of its carbon analog. Meanwhile, there is a noncovalent interaction between DTT and PEDOT:PSS, which remarkably suppressed the dissolution and enhanced the conductivity of DTT, thus leading to the great improvement of the electrochemical performance. The DTT cathode with the PEDOT:PSS binder displays a long‐term cycling stability (292 mAh g −1 for the first cycle, 266 mAh g −1 after 200 cycles at 0.1 C) and a high rate capability (220 mAh g −1 at 1 C). This design strategy based on a noncovalent interaction is very effective for the application of small organic molecules as the cathode of rechargeable lithium‐ion batteries. Abstract : A noncovalent interaction : A sulfur heterocyclic quinone compound (DTT) and a multifunctional binder (PEDOT:PSS) were prepared and used together as a high‐performance cathode in a rechargeable lithium‐ion battery (see picture). Through a noncovalent interaction between DTT and PEDOT:PSS the dissolution of DTT into an electrolyte was reduced and the conductivity of DTT was enhanced.