Review of the Real-Time Monitoring Technologies for Lithium Dendrites in Lithium-Ion Batteries.

Lithium-ion batteries (LIBs) have the advantage of high energy density, which has attracted the wide attention of researchers. Nevertheless, the growth of lithium dendrites on the anode surface causes short life and poor safety, which limits their application. Therefore, it is necessary to deeply understand the growth mechanism of lithium dendrites. Here, the growth mechanism of lithium dendrites is briefly summarized, and the real-time monitoring technologies of lithium dendrite growth in recent years are reviewed. The real-time monitoring technologies summarized here include in situ X-ray, in situ Raman, in situ resonance, in situ microscopy, in situ neutrons, and sensors, and their representative studies are summarized. This paper is expected to provide some guidance for the research of lithium dendrites, so as to promote the development of LIBs.

The effects of COVID-19 event strength on job burnout among primary medical staff.

BACKGROUND: As a global pandemic, The Corona Virus Disease 2019 (COVID-19) has brought significant challenges to the primary health care (PHC) system. Health professionals are constantly affected by the pandemic's harmful impact on their mental health and are at significant risk of job burnout. Therefore, it is essential to gain a comprehensive understanding of how their burnout was affected. The study aimed to examine the relationship between COVID-19 event strength and job burnout among PHC providers and to explore the single mediating effect of job stress and work engagement and the chain mediating effect of these two variables on this relationship. METHODS: Multilevel stratified convenience sampling method was used to recruit 1148 primary medical staff from 48 PHC institutions in Jilin Province, China. All participants completed questionnaires regarding sociodemographic characteristics, COVID-19 event strength, job stress, work engagement, and job burnout. The chain mediation model was analyzed using SPSS PROCESS 3.5 Macro Model 6. RESULTS: COVID-19 event strength not only positively predicted job burnout, but also indirectly influenced job burnout through the mediation of job stress and work engagement, thereby influencing job burnout through the "job stress → work engagement" chain. CONCLUSIONS: This study extends the application of event systems theory and enriches the literature about how the COVID-19 pandemic impacted PHC medical staff job burnout. The findings derived from our study have critical implications for current and future emergency response and public policy in the long-term COVID-19 disease management period.

A Single-Layer Composite Separator with 3D-Reinforced Microstructure for Practical High-Temperature Lithium Ion Batteries.

Incorporation of ceramic materials into separators has been frequently applied in both research and industry to improve the overall high-temperature performances of lithium ion batteries. However, inorganic ceramic particles tend to form aggregation in separators and even fall off in the separator matrix due to the inferior combination between ceramic particles and polymer matrix, giving rise to a decrease in separator porosity and thus the degradation of battery performances. Herein, a single-layer core-shell architecture is designed to reinforce the polymer matrix through encircling Al2 O3 particles by poly(vinylidene fluoride) with strong inter-molecular interaction. The 3D-reinforced microstructure effectively improves pore distribution and thermal stability to resist the dimensional deformation at high temperatures, thus giving rise to a high Coulombic efficiency of 99.16% and 87.5% capacity retention after 500 cycles at 80 °C for LiFePO4 /Li batteries. In particular, the excellent performances of the proposed separator microstructure are confirmed with a thickness value of commercial separators. This work provides a promising strategy to fabricate a core-shell structural composite separator for stable lithium ion batteries at high temperatures.

High-Polarity Fluoroalkyl Ether Electrolyte Enables Solvation-Free Li+ Transfer for High-Rate Lithium Metal Batteries.

Lithium metal batteries (LMBs) have aroused extensive interest in the field of energy storage owing to the ultrahigh anode capacity. However, strong solvation of Li+ and slow interfacial ion transfer associated with conventional electrolytes limit their long-cycle and high-rate capabilities. Herein an electrolyte system based on fluoroalkyl ether 2,2,2-trifluoroethyl-1,1,2,3,3,3-hexafluoropropyl ether (THE) and ether electrolytes is designed to effectively upgrade the long-cycle and high-rate performances of LMBs. THE owns large adsorption energy with ether-based solvents, thus reducing Li+ interaction and solvation in ether electrolytes. With THE rich in fluoroalkyl groups adjacent to oxygen atoms, the electrolyte owns ultrahigh polarity, enabling solvation-free Li+ transfer with a substantially decreased energy barrier and ten times enhancement in Li+ transference at the electrolyte/anode interface. In addition, the uniform adsorption of fluorine-rich THE on the anode and subsequent LiF formation suppress dendrite formation and stabilize the solid electrolyte interphase layer. With the electrolyte, the lithium metal battery with a LiFePO4 cathode delivers unprecedented cyclic performances with only 0.0012% capacity loss per cycle over 5000 cycles at 10 C. Such enhancement is consistently observed for LMBs with other mainstream electrodes including LiCoO2 and LiNi0.5 Mn0.3 Co0.2 O2 , suggesting the generality of the electrolyte design for battery applications.

Suppression of Polysulfide Dissolution and Shuttling with Glutamate Electrolyte for Lithium Sulfur Batteries.

The lithium sulfur battery is regarded as a potential next-generation high-energy battery system. However, polysulfides dissolve and shuttle through the electrolytes, causing rapid capacity decay, serious self-discharge, and poor high-temperature performances. Here, we demonstrate that by directly introducing glutamate into commercial electrolytes, these issues can be tackled simultaneously. With abundant negatively charged hydroxyl groups, the glutamate additive electrolyte effectively suppresses the shuttling of negatively charged polysulfide ions through strong repulsive interaction up to 1.54 eV. With glutamate additive electrolyte, the lithium sulfur battery has a capacity retention of 60% after 1000 cycles at 5.95 mA/cm2, a self-discharge rate on the order of one-third that of commercial electrolytes, and stable operation at 60 °C.