A High-Performance Li-O2 Battery with a Strongly Solvating Hexamethylphosphoramide Electrolyte and a LiPON-Protected Lithium Anode

Bin Zhou; Limin Guo; Yantao Zhang; Jiawei Wang; Lipo Ma; Wen-Hua Zhang; Zhengwen Fu; Zhangquan Peng

doi:10.1002/adma.201701568

A High-Performance Li-O₂ Battery with a Strongly Solvating Hexamethylphosphoramide Electrolyte and a LiPON-Protected Lithium Anode

Adv Mater. 2017 Aug;29(30). doi: 10.1002/adma.201701568. Epub 2017 Jun 6.

Authors

Bin Zhou^{1

2}, Limin Guo¹, Yantao Zhang¹, Jiawei Wang¹, Lipo Ma¹, Wen-Hua Zhang², Zhengwen Fu³, Zhangquan Peng¹

Affiliations

¹ State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, P. R. China.
² Sichuan Research Center of New Materials, Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang, Sichuan, 621900, P. R. China.
³ Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Department of Chemistry and Laser Chemistry, Fudan University, Shanghai, 200433, P. R. China.

PMID: 28585309
DOI: 10.1002/adma.201701568

Abstract

The aprotic Li-O₂ battery has attracted a great deal of interest because theoretically it can store more energy than today's Li-ion batteries. However, current Li-O₂ batteries suffer from passivation/clogging of the cathode by discharged Li₂ O₂ , high charging voltage for its subsequent oxidation, and accumulation of side reaction products (particularly Li₂ CO₃ and LiOH) upon cycling. Here, an advanced Li-O₂ battery with a hexamethylphosphoramide (HMPA) electrolyte is reported that can dissolve Li₂ O₂ , Li₂ CO₃ , and LiOH up to 0.35, 0.36, and 1.11 × 10^-3 m, respectively, and a LiPON-protected lithium anode that can be reversibly cycled in the HMPA electrolyte. Compared to the benchmark of ether-based Li-O₂ batteries, improved capacity, rate capability, voltaic efficiency, and cycle life are achieved for the HMPA-based Li-O₂ cells. More importantly, a combination of advanced research techniques provide compelling evidence that operation of the HMPA-based Li-O₂ battery is backed by nearly reversible formation/decomposition of Li₂ O₂ with negligible side reactions.

Keywords: Li-O2 batteries; LiPON-protected Li anodes; reversibility; strongly solvating electrolytes.