Improvement in Cycle Life of Organic Lithium-Ion Batteries by In-Cell Polymerization of Tetrathiafulvalene-Based Electrode Materials

• Published in: ACS applied materials & interfaces 2022-08, Vol.14 (31), p.35978-35984
• Main Authors: Yoshimura, Aya, Hemmi, Keisuke, Moriwaki, Hayato, Sakakibara, Ryo, Kimura, Hitoshi, Aso, Yuto, Kinoshita, Naoya, Suizu, Rie, Shirahata, Takashi, Yao, Masaru, Yorimitsu, Hideki, Awaga, Kunio, Misaki, Yohji
• Format: Article
• Language: English
• Subjects: Organic Electronic Devices
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.2c09302

Redox-active organic molecules are promising candidates for next-generation electrode materials. Nevertheless, finding low-molecular-weight organic materials with a long cycle life remains a crucial challenge. Herein, we demonstrate the application of tetrathiafulvalene and its vinyl analogue bearing triphenylamines as long-cycle-life electrodes for lithium-ion batteries (LIBs). These molecules were successfully synthesized using palladium-catalyzed C–H arylation. Electrochemical analysis revealed that a polymer formed on the electrode. LIBs comprising these molecules exhibited noteworthy charge–discharge properties with a long cycle life (the capacity after 100 cycles was greater than 90% of the discharge capacity in the third cycle) and a high utilization ratio (approximately 100%). “In-cell” polymerization during the first charge process is considered to contribute to the effect. This study indicates new avenues for the creation of organic materials for rechargeable batteries.