Al–Sc dual-doped LiGe₂(PO₄)₃ – a NASICON-type solid electrolyte with improved ionic conductivity

Abstract

A cell with doped LPS – Li1.5Al0.33Sc0.17Ge1.5(PO4)3 shows improved conductivity and a capacity retention of 83.6% for more than 80 cycles.

Chemical stability of sulfide solid-state electrolytes: stability toward humid air and compatibility with solvents and binders

“…Among them, oxide and sulfide solid electrolytes are the two most important categories, while oxide solid inorganic electrolytes can be further divided into garnet-type, NASICON-type, and perovskite-type solid electrolytes. Li + conductors of inorganic solid electrolytes like garnet-type, [23][24][25][26][27] perovskite-type, [28][29][30] and NASICON-type 18,[31][32][33][34][35][36] lithium phosphorus oxynitrides, [37][38][39][40][41] and sulfide solid electrolytes (S-SEs) [42][43][44][45][46] are massively studied and the pros and cons of these various types of solid-state electrolytes are briefly summarized in Table 1. In the case of solid electrolytes, the principal features are that they should be high Li + conductivity materials at ambient temperature with insignificant electronic conductivity.…”

Methods for Lithium Ion NASICON Preparation: From Solid-State Synthesis to Highly Conductive Glass-Ceramics

“…Traditional Li + -batteries comprise a liquid electrolyte, based on a solution of lithium salts dissolved in organic solvents . However, the toxicity and flammability of these electrolytes limit their use. ,− Solid-state electrolytes are safer and promising for use at room temperature and also at high temperatures. ,, Using them in all solid-state batteries can also provide a longer lifetime than liquid electrolyte-based devices. ,,,,− To construct these latter devices, efficient solid electrolytes must be developed. In general, they present lower conductivity than liquid electrolytes, but some types of materials show significant alkaline ion mobility. , These materials have become important candidates for further applications in these storage devices.…”

“…Nonetheless, the production of NASICON-type glass-ceramics is another strategy to prepare dense and high-performance electrolytes. The grain boundary resistance is highly reduced in these materials by controlling crystallization, with a preparation of specimens with low porosity and complex shapes, without the need for further sintering. ,, The liquid phase formed during a typical melting-quenching process also provides improved chemical homogeneity for the final electrolyte, similarly to the wet-chemical methods of synthesis. , The preparation of NASICON glass-ceramics has allowed electrolyte preparations with conductivities of more than 5 × 10 –3 S cm –1 . ,,, …”

The role of metal substitutions in the development of Li batteries, part II: solid electrolytes

“…The optimal composition of Li 1.5 Al 0.33 Sc 0.17 Ge 1.5 (PO 4 ) 3 shows higher conductivity than LGP due to the larger Li diffusion channel size and facilitating new diffusion channels direct 6b-36f path through which the Li ions move in concerted fashion instead moving through 18e by isolated single-ion diffusion. 150 One drawback of LGP is that it gets reduced when in contact with metallic lithium anodes yielding an electronically conductive material. 151 LiZr 2 (PO 4 ) 3 (LZP) has four polymorphs which are presented in Fig.…”