High Lithium-Ion-Conducting NASICON-Type Li1+xAlxGeyTi2−x−y(PO4)3 Solid Electrolyte

Abstract

A water-stable solid electrolyte is a key material without which aqueous lithium-air batteries could not be operated. In this study, we have examined the electrical conductivity and mechanical properties of a water-stable lithium-ion-conducting solid electrolyte, Li1+xAlxGeyTi2−x−y(PO4)3 with the NASICON-type structure, as a function of the Al and Ge content. Li1+xAlxGeyTi2−x−y(PO4)3 was synthesized by the conventional solid-state reaction method. The highest lithium-ion conductivity of 1.0 × 10 −3 S cm −1 at 25°C and the highest three-point bending strength of 90 N mm −2 at room temperature were observed for a pellet of Li1.45Al0.45Ge0.2Ti1.35(PO4)3 sintered at 900°C.

Synthesis and Properties of NaSICON‐type LATP and LAGP Solid Electrolytes

“…Moreover,L ATPa nd LAGP are employed as Li-ion conductors in composite solid electrolyte, anode,a nd cathode materials. [50,56,80,110,116] Increasing the conductive phase purity and decreasing the nonconductive secondary phase is another approach.2 )Byi mproving the interfacial stability of the electrolyte with aL im etal anode to reduce the interfacial resistance and prevent interfacial reactions. Figure 11.…”

“…However,t oa chieve the best battery performance, NaSICON-type solid electrolytes are expectedt o obtain further enhancement in severalw ays:1 )Byi ncreasing their conductivities to 10 À3 Scm À1 .M anya ttempts have been made to prepareL AGTP by partial substitution of Ge 4 + for Ti 4 + in LATP. [50,56,80,110,116] Increasing the conductive phase purity and decreasing the nonconductive secondary phase is another approach.2 )Byi mproving the interfacial stability of the electrolyte with aL im etal anode to reduce the interfacial resistance and prevent interfacial reactions. 3) By modification of the solid electrolyte contactsw ith cathode materials to increase ion mobility in cathode composites.…”

Superionic Diffusion through Frustrated Energy Landscape

“…Such resistive grain boundaries are often found in superionic conductors, such as garnet-and NASICON-based systems, and can be reduced by optimizing the sintering conditions. 48,49 Density Functional Theory computations and molecular dynamics All ab initio computations in this study were performed using density functional theory within the Projector Augmented Wave (PAW) 50 The molecular dynamics simulations were performed using a Verlet algorithm to integrate Newton's equations of motion, at a time step of 2 fs for a total simulation time of at least 200 ps on an NVT ensemble where we fix the number of atoms, the volume and the temperature [53][54][55] . We start all runs from a temperature of 100 K, rise it to the target temperature over a time period of 2 ps and then equilibrate the system at the target temperature for a time period of 10 ps before to start to sample diffusion data.…”

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

“…FIGURE 2 | X-ray diffraction (XRD) patterns of LAGTP, LAGTP-E, and LAGTP-E-LiCl. (Shang et al, 2016). Corresponding amounts of Li 2 CO 3 , TiO 2 , Al 2 O 3 , NH 4 H 2 PO 4 (Nakalai Tesque, Japan), and GeO 2 (Sigma Aldrich) were ball milled in isopropanol with zirconia balls in a zirconia vessel using a planetary micromill (Fritsch Pulverisette 7).…”