Stabilization of Garnet/Liquid Electrolyte Interface Using Superbase Additives for Hybrid Li Batteries

Biyi Xu; Huanan Duan; Hezhou Liu; Chang An Wang; Shengwen Zhong

doi:10.1021/acsami.7b05599

Stabilization of Garnet/Liquid Electrolyte Interface Using Superbase Additives for Hybrid Li Batteries

ACS Appl Mater Interfaces. 2017 Jun 28;9(25):21077-21082. doi: 10.1021/acsami.7b05599. Epub 2017 Jun 19.

Authors

Biyi Xu¹, Huanan Duan¹, Hezhou Liu¹, Chang An Wang², Shengwen Zhong³

Affiliations

¹ State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University , Shanghai 200240, P.R. China.
² State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University , Beijing 100084, P.R. China.
³ School of Materials Science and Engineering, Jiangxi University of Science and Technology , Ganzhou 341000, Jiangxi, P.R. China.

PMID: 28614651
DOI: 10.1021/acsami.7b05599

Abstract

To improve the solid-electrolyte/electrode interface compatibility, we have proposed the concept of hybrid electrolyte by including a small amount of liquid electrolyte in between. In this work, n-BuLi, a superbase, has been found to significantly improve the cycling performance of LiFePO₄/Li hybrid cells containing Li₇La₃Zr_1.5Ta_0.5O₁₂ (LLZT) and conventional carbonate-based liquid electrolyte. The modified cells have been cycled for 400 cycles at 100 and 200 μA cm^-2 at room temperature, indicating excellent solid/liquid electrolyte interface stability. The role of n-BuLi may be 3-fold: to retard the decomposition reaction of LE, to suppress the Li⁺/H⁺ exchange, and to lithiate the garnet/LE interface, inhibiting side reactions and enhancing interfacial lithium-ion transport.

Keywords: additives; cyclibility; hybrid electrolyte; interfacial resistance; lithium garnets.