Preparation of Li_1.3Al_0.3Ti_1.7(PO₄)₃ solid electrolyte via a sol-gel method using various Ti sources

Abstract

In this study, LATP (Li 1.3 Al 0.3 Ti 1.7 (PO 4) 3) solid electrolyte is prepared by a sol-gel process using Ti(C 2 H 5 O) 4 , Ti(n-C 3 H 7 O) 4 and Ti(n-C 4 H 9 O) 4 as Ti sources to examine the influence of the Ti source on the electrochemical properties of produced LATP. LATP is successfully produced in all cases, however, AlPO 4 impurity is formed in the Ti(n-C 3 H 7 O) 4 and Ti(n-C 4 H 9 O) 4 samples due to insufficient formation of Ti-O-Al network. In contrast, the AlPO 4 formation is not observed in the Ti(C 2 H 5 O) 4 sample. Also, the Ti(C 2 H 5 O) 4 sample shows the highest sinterability and the largest grain size among the three samples. As a result, the Ti(C 2 H 5 O) 4 sample shows the highest Li ion conductivity due to high grain boundary conductivity and less impurity phase. The selection of Ti source is a key to obtain high conductive LATP solid electrolyte.

Insights into the Effects of Co-Regulated Factors on Li1.3Al0.3Ti1.7(PO4)3 Solid Electrolyte Preparation: Sources, Calcination Temperatures, and Sintering Temperatures

“…23−25 In contrast, without sintering aids, the previous study reported an ionic conductivity of only 0.38 mS/cm for LATP at a sintering temperature of 1080 °C. 26 However, based on our insights from the above-mentioned reports, we find that these articles have omitted some important points that are crucial for laboratory preparation and the commercial manufacture of high-performance LATP solid electrolytes: (1) most researchers only investigate the effects of one or two important factors in their own studies, neglecting to discuss some other key parameters, 14,18 which may make it difficult for readers to replicate their results, and (2) too many articles focus on the influencing mechanism of individual process parameters, but none of them systematically and deeply discuss the relationship and interactions of these factors. 17,27 Although studying the effects of a certain synthesis factor is important and necessary, it is not sufficient.…”

“…However, based on our insights from the above-mentioned reports, we find that these articles have omitted some important points that are crucial for laboratory preparation and the commercial manufacture of high-performance LATP solid electrolytes: (1) most researchers only investigate the effects of one or two important factors in their own studies, neglecting to discuss some other key parameters, , which may make it difficult for readers to replicate their results, and (2) too many articles focus on the influencing mechanism of individual process parameters, but none of them systematically and deeply discuss the relationship and interactions of these factors. , Although studying the effects of a certain synthesis factor is important and necessary, it is not sufficient. Systematic research on the relative importance and the interactions amongst each of the important factors is also essential and can help us directly and effectively comprehend the whole preparation of LATP pellets from a new perspective.…”

“…The effect of different organic titaniums (e.g., Ti(C 2 H 5 O) 4 , Ti(n-C 3 H 7 O) 4 , and Ti(n-C 4 H 9 O) 4 ) as Ti sources on LATP performance was compared using sol−gel preparation, indicating that the secondary phase may depend on selecting Ti sources. 18 Lee et al found that LATP prepared with LiCl as the Li source had a smaller lattice volume and larger crystallite size without the secondary phase than those with LiNO 3 and Li(CH 3 COO). 20 Hamao et al used the alkaline material Al(OH) 3 as the Al source to form LATP but did not explore its role and secondary phase.…”

Understanding the Evolution of the Structure and Electrical Properties during Crystallization of Li1.5Al0.5Ge1.5(PO4)3 and Li1.5Sc0.17Al0.33Ge1.5(PO4)3 NASICON -Type Glass Ceramics

“…43 Depending on heat treatment temperature, this procedure avoids the appearance of secondary phases after the NASICON crystallization that could block the lithium-ion motion. 44 Moreover, this technique is a simple strategy to produce specimens with complex shapes and with efficient microstructural control through crystallization. 42,43 Once robust setups for the parent glass preparation and further crystallization are usually not required, glass ceramic technology is a promising scale-up technique for NASICON preparation.…”

“…Recently, there has been a vast body of literature on the production of NASICONs such as glass ceramics to obtain solid electrolytes. ,,,− The homogeneous melts provided by the preparation of the parent glass provide a high degree of compositional control . Depending on heat treatment temperature, this procedure avoids the appearance of secondary phases after the NASICON crystallization that could block the lithium-ion motion . Moreover, this technique is a simple strategy to produce specimens with complex shapes and with efficient microstructural control through crystallization. , Once robust setups for the parent glass preparation and further crystallization are usually not required, glass ceramic technology is a promising scale-up technique for NASICON preparation.…”