Insights into the sinterability and electrical properties of Li1.3Al0.3Ti1.7(PO4)3-(Li2CO3·Bi2O3) composite electrolytes

Optimizing Li1.3Al0.3Ti1.7(PO4)3 Particle Sizes toward High Ionic Conductivity

“…This circuit contained a single resistance R 1 describing the bulk ion transport in the grains. The grain boundary properties are represented by a parallel combination of a resistance R 2 and a constant-phase element CPE 1 . ,,,− Finally, a constant-phase element CPE 2 represented the electrode polarization. The equivalent circuit fit well for the semicircle at high frequency while imperfectly fitting the line at low frequency.…”

“…The LATP powders were prepared by the traditional solid-state reaction. ,,− Precursor powders of LiOH·H 2 O (AR, 98%, Aladdin), Al 2 O 3 (AR, 20 nm, 99%, Aladdin), TiO 2 (AR, 20 nm, 99%, Aladdin), and NH 4 H 2 PO 4 (AR, 99%, Aladdin) with a stoichiometry of Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 (∼200 g) with 5% excess Li and 2 g of sucrose (AR, Aladdin) were ball milled at 200 rpm for 12 h with isopropanol (IPA, 300 g) as the solvent and yttrium-stabilized zirconium oxide (YSZ) beads (Φ 10 mm, 100 g; Φ 5 mm, 600 g) as the milling media. The container was a nylon tank with 110 × 100 mm (φ × h ) inner dimensions, and the planetary milling machine was YXQM-8L with a φ 420 mm solar diameter.…”

“…Among oxide SSEs, the NASICON-type SSE LATP has been extensively studied for its high ionic conductivity, good chemical stability, and wide electrochemical window, which is obtained by replacing Ti 4+ in LTP with Al 3+ doping and increasing the lithium ions in the lattice to balance the charge, thus increasing the conductivity. − The crystal structure of LATP belongs to the R 3̅ c space group, consisting of [PO 4 ] tetrahedra and [TiO 6 ] octahedra connected at common angles to form a three-dimensional space framework, with the Li + migration channel parallel to the c axis. , Studies demonstrate that the Li + bulk conductivity of LATP is intrinsic and is mainly based on the incorporation of the additional Li + as highly mobile charge carriers within the fast diffusion pathways. , In this structure, lithium ions are located in two positions, namely, Li 1 (Wyckoff 6b) and Li 2 (Wyckoff 36f) . It has been demonstrated recently that lithium-ion conduction involves both sites according to a Li 1 –Li 2 –Li 2 –Li 1 zigzag pathway. , The relationship between the powder particle size and the Li + conductivity of ceramics has rarely been investigated.…”

Borosilicate Glass-Enabled Antifracture NASICON Solid Electrolytes for Lithium-Metal Batteries

“…Solid electrolytes provide a new direction for solving the safety problems of liquid electrolytes. − Especially, sodium superionic conductor (NASICON) solid electrolytes own a high Li + transference number, , better electrochemical stability, , excellent kinetics, and especially higher safety. − Traditional pressureless sintering usually leads to poor-quality NASICON solid electrolytes (low density and mechanical strength), which limits the application of NASICON solid electrolytes. , Recently, many effective strategies have been reported to improve the quality of sintering, including sintering additives, sol–gel method, spark plasma sintering, , high-temperature hot-press sintering process, and so on. However, these methods are costly, energy-consuming, and not a benign choice for mass production.…”

“…29−31 Traditional pressureless sintering usually leads to poor-quality NASICON solid electrolytes (low density and mechanical strength), which limits the application of NASICON solid electrolytes. 32,33 Recently, many effective strategies have been reported to improve the quality of sintering, including sintering additives, 34 sol−gel method, 35 spark plasma sintering, 36,37 high-temperature hot-press sintering process, 38 and so on. However, these methods are costly, energy-consuming, and not a benign choice for mass production.…”