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Garnet-type solid electrolytes have garnered significant interest for all-solid-state battery applications due to their high Li-ion conductivity and excellent compatibility with the metallic lithium anode. Although their ionic conductivity optimization and conduction mechanisms have been extensively studied, the thermal properties of garnet electrolytes remain poorly understood. The thermal conductivity, thermal expansion coefficient, and specific heat of solid electrolytes play a crucial role in determining the overall performance, safety, and reliability of battery devices. Understanding these properties is essential for enhanced thermal management and improved energy efficiency of batteries. Here, we investigate the thermal properties of Ta5+-doped garnet Li6.5La3Zr1.5Ta0.5O12 (LLZTO) polycrystals. The thermal conductivity measurement reveals a low-temperature peak at around 50 K. Above this temperature, the thermal conductivity shows a weak temperature dependence and approaches the calculated minimum thermal conductivity. The average phonon mean free path increases as the temperature decreases, reaching approximately 500 nm at 5 K. The linear thermal expansion coefficient obtained through the X-ray diffraction measurements is 1.71 ± 0.01 × 10−5 K−1 at 323 K, larger than the reported value for undoped Li7La3Zr2O12. The Grüneisen parameter of LLZTO calculated using the measured thermal expansion coefficient and specific heat is 1.63 ± 0.04 at 300 K, indicating relatively strong phonon anharmonicity. Furthermore, the thermal conductivity of aged LLZTO is increased by 70–80% at 300 K compared to the pristine samples, which can be attributed to the formation of Li2CO3 with increased thermal conductivity or reduced thermal boundary resistance. Our results provide useful insights into the structure–thermal property relationships that are closely relevant to thermal management of battery systems based on garnet solid electrolytes. [ABSTRACT FROM AUTHOR]

The colorations of stem pubescence and hilum are crucial criteria for discerning diverse soybean germplasms, governed by multiple genes that substantially influence the seed's outward appearance quality and the resistance to abiotic stresses. This comprehensive study delved into the stem pubescence and hilum color traits across a natural population of 264 accessions during 2021 and 2022. The phenotypes of these two traits within our population were analyzed for the investigation of population genetics and evaluation of germplasm resources in the future. Numerous noteworthy SNPs associated with both traits were detected through a genome-wide association study (GWAS), with the most significant signals for 2021 and 2022 localized on chromosome 6. Seven candidate genes regulating stem pubescence color and four genes influencing hilum color were identified by analyzing the expression patterns, cold stress responses, and regulatory pathways of genes within the LD decay distance of SNPs. This study not only underscores the applicability of GWAS in unraveling the genetic basis of quality traits, but also contributes novel genetic reservoirs and research paradigms to the explorations of the soybean plant and seed color. These results provide foundational insights into the breeding improvement of seeds' outward appearance quality and a comprehensive evaluation of soybean germplasm. [ABSTRACT FROM AUTHOR]