Zhang Kai, Guo Chunyang, Zhao Qing, Niu Zhiqiang, Chen Jun
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Collaborative Innovation Center of Chemical Science and Engineering Nankai University Tianjin 300071 China.
Adv Sci (Weinh). 2015 Apr 15;2(5):1500018. doi: 10.1002/advs.201500018. eCollection 2015 May.
Organic carbonyl electrode materials of lithium batteries have shown multifunctional molecule design and high capacity, but have the problems of poor cycling and low rate performance due to their high solubility in traditional carbonate-based electrolytes and low conductivity. High-performance organic lithium batteries with modified ether-based electrolyte (2 m LiN(CFSO) in 1,3-dioxolane/dimethoxyethane solvent with 1% LiNO additive (2m-DD-1%L)) and 9,10-anthraquinone (AQ)/CMK-3 (AQC) nanocomposite cathode are reported here. The electrochemical results manifest that 2m-DD-1%L electrolyte promotes the cycling performance due to the restraint of AQ dissolution in ether-based electrolyte with high Li salt concentration and formation of a protection film on the surface of the anode. Additionally, the AQC nanocomposite improves the rate performance because of the nanoconfinement effect of CMK-3 and the decrease of charge transfer impedance. In 2m-DD-1%L electrolyte, AQC nanocomposite delivers an initial discharge capacity of 205 mA h g and a capacity of 174 mA h g after 100 cycles at 0.2 C. Even at a high rate of 2 C, its capacity is 146 mA h g. This strategy is also used for other organic carbonyl compounds with quinone substructures and they maintain high stable capacities. This sheds light on the development of advanced organic lithium batteries with carbonyl electrode materials and ether-based electrolytes.
锂电池的有机羰基电极材料已展现出多功能分子设计和高容量,但由于其在传统碳酸盐基电解质中的高溶解度和低电导率,存在循环性能差和倍率性能低的问题。本文报道了具有改性醚基电解质(在1,3 - 二氧戊环/二甲氧基乙烷溶剂中含2 m LiN(CFSO) 及1% LiNO添加剂(2m - DD - 1%L))和9,10 - 蒽醌(AQ)/CMK - 3(AQC)纳米复合阴极的高性能有机锂电池。电化学结果表明,2m - DD - 1%L电解质由于在高锂盐浓度的醚基电解质中抑制了AQ的溶解,并在阳极表面形成保护膜,从而提升了循环性能。此外,AQC纳米复合材料由于CMK - 3的纳米限域效应和电荷转移阻抗的降低,改善了倍率性能。在2m - DD - 1%L电解质中,AQC纳米复合材料在0.2 C下首次放电容量为205 mA h g,100次循环后容量为174 mA h g。即使在2 C的高倍率下,其容量仍为146 mA h g。该策略还用于其他具有醌亚结构的有机羰基化合物,它们保持了高稳定容量。这为开发具有羰基电极材料和醚基电解质的先进有机锂电池提供了思路。