Huanhuan Gao,Jianzhong Liu,Peihui Xu,Haiou Wang,Jianren Fan
Aluminum-lithium (Al–Li) alloys are crafted by incorporating minute quantities of Li into Al, thereby alleviating the passivation effect of dense alumina. This strategic blend elevates the energy release potential of Al-based fuels by enhancing reactivity and facilitating efficient combustion reactions. The effects of Li content and particle size on the combustion characteristics of Al–Li alloys are systematically investigated, with a particular focus on several pivotal aspects: thermal oxidation behavior, ignition delay time, combustion time, combustion intensity, temperature, and the condensed-phase products. The results show that, upon heating to 1500°C, the oxidation weight gain of Al–Li alloys reaches 6.5 times that of raw Al. This indicates that adding Li significantly enhances the extent of the oxidation reaction. Increased Li content and particle size reduction further accelerate the oxidation reaction. The ignition delay time and combustion time are effectively shortened, showing a more intense combustion process, higher flame temperature and more significant micro-explosion effect. Ultimately, these factors lead to a significant reduction in the size of condensed-phase products. Based on these insights, a comprehensive impact mechanism for the energy release of Al–Li alloys has been proposed, providing theoretical guidance for applying Al–Li alloys in related fields.
Fengsheng Zeng,Qi Yuan,Hadi Barzegar-Bafrooei,Mahdi Feizpour,Fayaz Hussain,Yasemin Tabak,Atilla Evcin,Viktor Sergeevich,Kaixin Song
Ceramics of Li 2+ x Mg 2 Mo 3 O 12 (L x MM, 0 ≤ x ≤ 0.05) were prepared via a conventional solid-state method at 625-650 °C. XRD and Raman spectroscopy were utilized to characterize the phase composition, crystal structure changes, and lattice vibrations of the ceramics. The results indicated that as the Li content increased, the damping coefficient of the lattice decreased, leading to a reduction in the intrinsic loss of the ceramics. For x ≤ 0.02, an increase in x resulted in an increase in the relative permittivity of the ceramic, while the theoretical permittivity decreased. Moreover, the quality factor progressively increased, and the temperature coefficient of the resonant frequency neared zero. This behavior is ascribed to the enlarged cell volume, diminished lattice strain, and decreased bond valence. However, when x ≥ 0.03, the emergence of a new Li 2 MoO 4 phase led to a deterioration in the microwave dielectric properties of the ceramics. The optimal microwave dielectric properties were achieved at x = 0.02, with ε r = 9.17, Q×f = 70,536 [email protected] GHz, and τ f = -51.2 ppm/°C.
Considering the high ion conductivity and good machining properties of lithium thiophosphate (LPS), it has attracted increasing attention as a solid electrolyte for all-solid-state batteries. Chemical and thermal stability can be significantly enhanced by increasing lithium content. However, in past reports, the lithium content of LPS is commonly less than 40 %. LPS with high lithium content (Li > 40 at%) shows low ion conductivity and high grain boundary resistance. In the present work, LPS with 47.2 at% lithium was prepared by cryomilling and solid-state reaction, avoiding crystallization and adhesion in the ball milling process. By improving the ball milling process, the ion conductivity (1.36 mS/cm) and ion activation energy (10.80 kJ/mol) were optimized by 106.1 % and 41.5 %, respectively. The resulting all-solid-state battery showed a high capacity retention of 104 % after 100 cycles.
危险品化学品经营许可证（带存储）