Superionic Solid Electrolyte Li7La3Zr2O12 Synthesis and Thermodynamics for Application in All-Solid-State Lithium-Ion Batteries

Abstract

Solid-state reaction was used for Li7La3Zr2O12 material synthesis from Li2CO3, La2O3 and ZrO2 powders. Phase investigation of Li7La3Zr2O12 was carried out by x-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS) methods. The thermodynamic characteristics were investigated by calorimetry measurements. The molar heat capacity (Cp,m), the standard enthalpy of formation from binary compounds (ΔoxHLLZO) and from elements (ΔfHLLZO), entropy (S0298), the Gibbs free energy of the Li7La3Zr2O12 formation (∆f G0298) and the Gibbs free energy of the LLZO reaction with metallic Li (∆rGLLZO/Li) were determined. The corresponding values are Cp,m = 518.135 + 0.599 × T − 8.339 × T−2, (temperature range is 298–800 K), ΔoxHLLZO = −186.4 kJ·mol−1, ΔfHLLZO = −9327.65 ± 7.9 kJ·mol−1, S0298 = 362.3 J·mol−1·K−1, ∆f G0298 = −9435.6 kJ·mol−1, and ∆rGLLZO/Li = 8.2 kJ·mol−1, respectively. Thermodynamic performance shows the possibility of Li7La3Zr2O12 usage in lithium-ion batteries.

Cold Sintering Enables the Reprocessing of LLZO‐Based Composites

“…The emissions and raw materials associated with all materials, processes, and wastes are quantified using the ecoinvent database accessed via OpenLCA [23] . Literature data and patents were also used to model the production of PPC, LLZO, and LiClO 4 [24–26] . The estimated energy consumption calculation can be found in the Supporting Information.…”

“…[23] Literature data and patents were also used to model the production of PPC, LLZO, and LiClO 4 . [24][25][26] The estimated energy consumption calculation can be found in the Supporting Information.…”

Investigation of Low‐Temperature Synthesis Strategy for a Cubic Phase Li7La3Zr2O12

“…The solid‐state reaction method proceeds according to Equation (1). [ 33 ] $$$$\begin{equation}7{\mathrm{Li}}_2{\mathrm{CO}}_3 + 3{\mathrm{La}}_2{{\mathrm{O}}}_3 + 4{\mathrm{ZrO}}_2 \to 2{\mathrm{Li}}_7{\mathrm{La}}_3{\mathrm{Zr}}_2{{\mathrm{O}}}_{12} + 7{\mathrm{CO}}_2\end{equation}$$$$…”