Balance cathode-active and anode-active groups in one conjugated polymer towards high-performance all-organic lithium-ion batteries

• Published in: Nano energy Vol. 86; p. 106055
• Main Authors: Zhao, Yang, Wu, Manman, Chen, Hongbin, Zhu, Jie, Liu, Jie, Ye, Zhantong, Zhang, Yan, Zhang, Hongtao, Ma, Yanfeng, Li, Chenxi, Chen, Yongsheng
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-08-2021
• Subjects: Energy storage; Full batteries; High capacity; Lithium-ion batteries; Organic electrodes; Lithium-ion batteries; Full batteries; High capacity; Organic electrodes; Energy storage
• ISSN: 2211-2855
• DOI: 10.1016/j.nanoen.2021.106055

Organic electrode materials are promising for future rechargeable batteries owing to their potential high capacity, tunable structure, flexibility and sustainability. Thus, developing high-performance all-organic batteries is highly demanded. But so far it is still a great challenge to achieve simultaneously such desired capacities and cycling stability, particularly for the case of all-organic symmetric batteries. Here, we design and report a polymer, named Poly-BQ1, which can be used as both cathode and anode materials for high-performance all-organic symmetric Lithium-ion battery. Such a two-fold electrode material was designed and optimized by balancing/maximizing abundant cathode-active groups (C˭O, C˭N) and anode-active groups (C˭C) in one stable conjugated polymer for both the purposes of achieving high capacity and cycling stability. Thus, owing to optimized integration of redox-active C˭O, C˭N and C˭C groups in a stable conjugated backbone and minimized redox-inactive units, the all-organic battery using this single material exhibits the highest capacity (351.5 mA h g−1 at 50 mA g−1) among all previously reported all-organic batteries with also remarkable cycling stability (99.96% retention per cycle up to 400 cycles) and rate performance (203.4 mA h g−1 at 1 A g−1).
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•A strategy for the design of all-organic batteries materials with simultaneously high capacity and stability is proposed.•Poly-BQ1 contains maximum redox-active groups (C=O, C=N and C=C), minimum redox-inactive units and stable backbone.•The all-organic symmetric battery is fabricated by using Poly-BQ1 as both cathode and anode materials.•The all-organic symmetric battery shows the highest capacity (351.5 mA h g-1 at 50 mA g-1), good cycle and rate performance.