Solid-State Polymer Electrolyte Solves the Transfer of Lithium Ions between the Solid–Solid Interface of the Electrode and the Electrolyte in Lithium–Sulfur and Lithium-Ion Batteries,ACS Applied Energy Materials

当前位置： X-MOL 学术 › ACS Appl. Energy Mater. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Solid-State Polymer Electrolyte Solves the Transfer of Lithium Ions between the Solid–Solid Interface of the Electrode and the Electrolyte in Lithium–Sulfur and Lithium-Ion Batteries
ACS Applied Energy Materials ( IF 5.4 ) Pub Date : 2021-04-15 , DOI: 10.1021/acsaem.1c00658
Yuhang. Shan ₁ , Libo. Li ₁ , Xueying. Yang ₁

Affiliation

The use of secondary batteries has been on the rise in recent years, especially solid-state batteries. However, security issues have become a major challenge in practical applications. Both lithium-ion batteries and lithium–sulfur batteries have safety problems that need to be solved. Herein, a polymer electrolyte suitable for the two types of batteries was easily synthesized. A polyvinylidene fluoride (PVDF)-based polymer electrolyte with 1-butyl-1-methyl pyrrolidine bis-trifluoromethyl sulfonimide (Py₁₄TFSI) was used as the solid electrolyte. The ionic conductivity of the LiTFSI/Py₁₄TFSI/cellulose acetate (CA)/PVDF polymer electrolyte was 1.45 × 10^–4 S cm^–1. The electrochemical stability window was 4.95 V. The transference number of the lithium ion was 0.231. The constant-current polarization test results showed that the polarization voltage was only 0.04 V when the current density was 1 mA cm^–2. The first discharge specific capacity of the Li | LiTFSI/Py₁₄TFSI/CA/PVDF | LiFePO₄ battery was 125.7 mA h g^–1 (0.5 C), and the capacity retention rate was 95.22% after 50 cycles at room temperature. A multistage porous conductive carbon (M-PCC) material with micropores and mesopores was applied as the host of the sulfur cathode of lithium–sulfur batteries. The M-PCC material provided a carrier for sulfur and sulfide with a specific surface area of 1132.68 m² g^–1. The solid-state lithium–sulfur battery (Li | LiTFSI/Py₁₄TFSI/CA/PVDF | S@M-PCC) had excellent electrochemical performance. The first discharge specific capacity was 1245.9 mA h g^–1 with an average Coulombic efficiency of 97.34%. The energy of Py₁₄TFSI cation and Li₂S₈ calculated by DFT was 8.8345 eV, which indicated that the polysulfide cannot adsorb onto the polymer electrolyte. XPS was used to measure the elemental composition of the anode–electrolyte interface after charge–discharge cycling. The uniform growth of lithium dendrite was observed by the SEM image of the anode after cycles. The results showed that a solid-state lithium–sulfur battery produced uniform solid electrolyte interface films and completely suppressed the shuttle effect.

中文翻译：

固态聚合物电解质解决了锂-硫和锂离子电池中电极的固-固界面与电解质之间的锂离子转移

近年来，二次电池的使用一直在增长，特别是固态电池。但是，安全性问题已成为实际应用中的主要挑战。锂离子电池和锂硫电池都有安全问题需要解决。在此，容易合成适用于两种电池的高分子电解质。将具有1-丁基-1-甲基吡咯烷双-三氟甲基磺酰亚胺（Py ₁₄ TFSI）的聚偏二氟乙烯（PVDF）基聚合物电解质用作固体电解质。LiTFSI / Py ₁₄ TFSI /醋酸纤维素（CA）/ PVDF聚合物电解质的离子电导率为1.45×10 ^–4 S cm ^–1。电化学稳定性窗口为4.95V。锂离子的转移数为0.231。恒流极化测试结果表明，当电流密度为1 mA cm ^–2时，极化电压仅为0.04V 。锂的第一放电比容量 LiTFSI / Py ₁₄ TFSI / CA / PVDF | LiFePO ₄电池为125.7 mA hg ^–1（0.5 C），在室温下经过50个循环后，容量保持率为95.22％。具有微孔和中孔的多级多孔导电碳（M-PCC）材料被用作锂硫电池硫磺阴极的主体。M-PCC材料提供了硫和硫化物的载体，比表面积为1132.68 m ² g^–1。固态锂硫电池（Li | LiTFSI / Py ₁₄ TFSI / CA / PVDF | S @ M-PCC）具有出色的电化学性能。首次放电比容量为1245.9 mA hg ^–1，平均库仑效率为97.34％。Py ₁₄ TFSI阳离子和Li ₂ S ₈的能量通过DFT计算的结果为8.8345eV，这表明多硫化物不能吸附到聚合物电解质上。XPS用于测量充放电循环后阳极-电解质界面的元素组成。循环后通过阳极的SEM图像观察到锂枝晶的均匀生长。结果表明，固态锂硫电池可产生均匀的固体电解质界面膜，并完全抑制了穿梭效应。

更新日期：2021-05-24

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南