Department of Chemistry, University of Toronto , 80 St. George Street, Toronto, Ontario M5S 3H6, Canada.
ACS Appl Mater Interfaces. 2017 May 10;9(18):15631-15637. doi: 10.1021/acsami.7b02336. Epub 2017 May 2.
Lithium ion batteries are the best commercial technology to satisfy the energy storage needs of current and emerging applications. However, the use of transition-metal-based cathodes precludes them from being low-cost, sustainable, and environmentally benign, even with recycling programs in place. In this study, we report a highly stable organic material that can be used in place of the transition-metal cathodes. By creating a three-dimensional framework based on triptycene and perylene diimide (PDI), a cathode can be constructed that mitigates stability issues that organic electrodes typically suffer from. When a lithium ion battery is assembled using the PDI-triptycene framework (PDI-Tc) cathode, a capacity of 75.9 mAh g (78.7% of the theoretical value) is obtained. Importantly, the battery retains a near perfect Coulombic efficiency and >80% of its capacity after cycling 500 times, which is the best value reported to date for PDI-based materials.
锂离子电池是满足当前和新兴应用储能需求的最佳商业技术。然而,即使有回收计划,基于过渡金属的阴极也无法做到低成本、可持续和环境友好。在本研究中,我们报告了一种高度稳定的有机材料,可用作过渡金属阴极的替代品。通过创建基于三并苯和苝二酰亚胺(PDI)的三维框架,可以构建一个减轻有机电极通常存在的稳定性问题的阴极。当使用 PDI-三并苯框架(PDI-Tc)阴极组装锂离子电池时,可获得 75.9 mAh g 的容量(理论值的 78.7%)。重要的是,该电池在循环 500 次后仍保持近乎完美的库仑效率和 >80%的容量,这是迄今为止 PDI 基材料的最佳值。