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High‐energy‐density lithium‐ion batteries (LIBs) with high safety have long been pursued for extending the cruise range of electric vehicles. Owing to the high gravimetric capacity, silicon is a promising alternative to the convention graphite anode for high‐energy LIBs. However, it suffers from intrinsic poor interfacial stability with liquid electrolytes, inevitably increasing the risk of thermal runaway and posing serious safety challenges. In this review, we will focus on mitigating thermal runaway of silicon anodes‐based LIBs from the perspective of electrolyte design. First, the thermal runaway mechanism of LIBs is briefly introduced, while the specific thermal failure reactions associated with silicon anodes and electrolytes are discussed in detail. We then summarize the safety countermeasures (e. g., thermally stable solid electrolyte interphase, nonflammable electrolytes, highly stable lithium salts, mitigating electrode crosstalk, and solid‐state electrolytes) enabled by customized electrolyte design to address these triggers of thermal runaway. Finally, the remaining unanswered questions regarding the thermal runaway mechanism are presented, and future directions to achieve intrinsically safe electrolytes for silicon‐based anodes are prospected. This review is expected to provide insightful knowledge for improving the safety of LIBs with silicon‐based anodes. [ABSTRACT FROM AUTHOR]

Barium strontium titanate glass-ceramics with different La2O3 contents (0, 0.5, 1.0, and 1.5 mol. %) were prepared by the melt-quenching technique. The phase developments, microstructures, and impedance behavior of these glass-ceramics have been investigated as a function of La2O3 content. By the X-ray diffraction study, a gradual change with increasing La2O3 content was observed. X-ray photoelectron spectroscopy indicated that the oxygen vacancy concentration decreases with the increase of La2O3 content. Lanthanum substitution resulted in an initial increase and then a decrease in the value of dielectric constant. From impedance spectroscopy, there are two electrical responses occurring: a low frequency response, which is related to the crystal-glass interface, and a high frequency response corresponding to the crystal phase. The low frequency peak shifts to lower frequencies and the high frequency peak shifts to higher frequencies with increasing lanthanum content. Both the temperature sensitivity of impedance and the value of ac conductivity decrease with the increase of La2O3 content. [ABSTRACT FROM AUTHOR]

This article, titled "High-Safety Lithium-Ion Batteries with Silicon-Based Anodes Enabled by Electrolyte Design," discusses the potential of using silicon as an alternative to graphite in lithium-ion batteries (LIBs) due to its high capacity. However, silicon anodes have poor stability with liquid electrolytes, which increases the risk of thermal runaway and poses safety challenges. The article explores the thermal runaway mechanism of LIBs, specific thermal failure reactions associated with silicon anodes and electrolytes, and safety countermeasures. It also highlights unanswered questions and future directions for achieving safe electrolytes for silicon-based anodes. The full article provides more in-depth information on these topics. [Extracted from the article]

Thermally stimulated depolarization current (TSDC) experiments were carried out to investigate the effect of polarization temperature on different relaxation processes in barium strontium titanate glass‐ceramics. It was found that all the TSDC curves are composed of four relaxation peaks. From the characteristics of peak temperature and peak current intensity with various polarization temperatures, the origin of these four peaks are identified as from defect dipole orientation, charge carrier detrapping, in‐crystal oxygen vacancy migration, and trans‐interface oxygen vacancy migration respectively. In addition, both the dipole concentration and trap density for the glass‐ceramic samples were estimated. [ABSTRACT FROM AUTHOR]