Water-Stable High Lithium-Ion Conducting Solid Electrolyte of Li1.4Al0.4Ge0.2Ti1.4(PO4)3–LiCl for Aqueous Lithium-Air Batteries

Fan Bai,Daisuke Mori,Hironari Minami,Osamu Yamamoto,Yasuo Takeda,Hiroaki Izumi,Kouichi Kakimoto,Nobuyuki Imanishi,Sou Taminato,Xuefu Shang,Mitsuhiro Matsumoto

doi:10.3389/fenrg.2020.00187

Fan Bai, Daisuke Mori + Show 9 more

Open Access

https://doi.org/10.3389/fenrg.2020.00187

Copy DOI

Abstract

Aqueous lithium-air batteries are one of the most promising batteries for electric vehicles because of its high energy and power density. The battery system consists of a lithium anode and an aqueous solution catholyte, which are separated by a water-stable lithium-ion conducting solid electrolyte, and an air electrode. The theoretical energy density of this system is 1910 Wh kg-1, which is around 5 times higher than that of conventional lithium-ion batteries. A key component of this system is the water-stable lithium-ion conducting solid electrolyte. In this work, we have developed a water-stable and water-impermeable solid electrolyte with a high lithium-ion conductivity of around 10-3 S cm-1 at room temperature by the addition of epoxy resin and LiCl into a tape-cast NASICON-type Li1.4Al0.4Ge0.2Ti1.4(PO4)3 film. The aqueous lithium-air battery with the solid electrolyte separator was successfully cycled at 0.5 mA cm-2 and 25 ℃ in an air atmosphere.

Highlights

The non-aqueous lithium-air system has the highest theoretical specific energy density, which is as high as 3,505 W h kg−1 and 3,436 W h L−1; this system requires an air purification system or oxygen tank (Gallagher et al, 2014)
Li1 + xAlxTi2 − x(PO4)3 (LATP) and La2/3 − xLi3xTiO3 (LLTO) are unstable in contact with lithium (Imanishi et al, 2008); these solid electrolytes require a lithium-stable interlayer between the lithium metal anode and the water-stable solid electrolyte
These results indicate that the element distributions were homogeneous, and LiCl may be homogeneously distributed over the sample at the grain boundaries

Summary

INTRODUCTION

Several types of high-energy-density batteries, such as lithium–sulfur (Yamin et al, 1988; Shim et al, 2002), non-aqueous lithium-air (Abraham and Jiang, 1996; Lu et al, 2014; Gao et al, 2017), aqueous lithium-air (Visco et al, 2004; Zhang et al, 2010), and all-solid-state (Takada, 2013; Kato et al, 2016) batteries have been extensively studied in the last few decades. The. Lithium-Ion Conducting Solid Electrolyte aqueous lithium-air battery is one attractive candidate for application as the power source in electric vehicles because of its high energy and power densities. The lithium anode and the catholyte were separated by a water-stable NASICON-type lithium-ion conducting solid electrolyte. The requirements of the solid electrolyte separator are as follows: high lithium-ion and low electron conductivity, stability in contact with lithium metal, ease of thin film preparation, excellent mechanical properties, and stability in contact with water. A waterstable and water-impermeable high lithium-ion-conducting solid electrolyte has been developed by the addition of epoxy resin with LiCl into a Li1.4Al0,4Ge0.2Ti1.4(PO4) (LAGTP) tapecast film. The charge and discharge performance of a Li/interlayer electrolyte/LAGTP with epoxy and LiCl/saturated LiCl and LiOH aqueous solution/carbon, air cell has been demonstrated. The (LiFSI-2G4)–50 vol% DOL interlayer was reported to suppress lithium dendrite formation (Wang et al, 2017)

RESULTS AND DISCUSSION

CONCLUSION

DATA AVAILABILITY STATEMENT