Department of Materials Science and Engineering, Chonnam National University, 77, Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea.
Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK.
Adv Sci (Weinh). 2022 May;9(13):e2105448. doi: 10.1002/advs.202105448. Epub 2022 Mar 3.
In this study, tetraethylene glycol dimethyl ether (TEGDME) is demonstrated as an effective additive in poly(propylene carbonate) (PPC) polymers for the enhancement of ionic conductivity and interfacial stability and a tissue membrane is used as a backbone to maintain the mechanical strength of the solid polymer electrolytes (SPEs). TEGDME in the PPC allows the uniform distribution of conductive LiF species throughout the cathode electrolyte interface (CEI) layer which plays a critically important role in the formation of a stable and efficient CEI. In addition, the high modulus of SPEs suppresses the formation of a protrusion-type CEI on the cathode. The SPE with the optimized TEGDME content exhibits a high ionic conductivity of 0.89 mS cm , an adequate potential stability of up to 4.89 V, and a high Li-ion transference number of 0.81 at 60 °C. Moreover, the Li/SPE/Li cell demonstrates excellent cycling stability for 1650 h, and the Li/SPE/LFP full cell exhibits an initial reversible capacity of 103 mAh g and improved stability over 500 cycles at a rate of 1 C. The TEGDME additive improves the electrochemical properties of the SPEs and promotes the creation of a stable interface, which is crucial for ASSLIBs.
在这项研究中,四甘醇二甲醚(TEGDME)被证明是聚(碳酸丙烯酯)(PPC)聚合物中的一种有效添加剂,可提高离子电导率和界面稳定性,并且使用组织膜作为骨架来维持固体聚合物电解质(SPE)的机械强度。PPC 中的 TEGDME 允许导电 LiF 物质在整个阴极电解质界面(CEI)层中均匀分布,这对形成稳定有效的 CEI 起着至关重要的作用。此外,SPE 的高模量抑制了在阴极上形成突出型 CEI。具有优化 TEGDME 含量的 SPE 表现出 0.89 mS cm 的高离子电导率、高达 4.89 V 的足够的电位稳定性以及在 60°C 时 0.81 的高锂离子迁移数。此外,Li/SPE/Li 电池在 1650 h 内表现出出色的循环稳定性,Li/SPE/LFP 全电池在 1 C 的倍率下具有初始可逆容量为 103 mAh g 和经过 500 次循环后的稳定性提高。TEGDME 添加剂改善了 SPE 的电化学性能并促进了稳定界面的形成,这对 ASSLIBs 至关重要。